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  • 1.
    Abdulla, Zine
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Varför blir inte detaljplanelagd mark för bostadsändamål bebyggd?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    According to Boverket's housing market survey 2018, which is a result of a national survey of the housing market in Sweden, there is a deficit in housing in 243 of Sweden's 290 municipalities. In order to meet increased demand for housing, increased housing construction is needed. Detailed development plans govern the rights, construction rights, which indicate what and to what extent property owners can build land. Detailed development plans are the legally binding documents that are established and adopted by municipalities in order to determine, among others, the use of land and water areas. There are several reasons for housing shortage and one is that Sweden's population continues to increase, both due to natural population growth and because of immigration. A growing population entails, for instance, an increase in housing demand, which in turn places demands on the housing market. The demand and supply of housing need to match each other. Another reason is that today it is the private sector that accounts for the majority of housing supply. The private sector does not have the responsibility that municipalities have in terms of meeting the residents' housing needs. The private actors intend to make a profit. Consequently, privately owned construction and housing companies build when it is economically beneficial and not just because there is a housing requirement. Due to the fact that there are still housing shortages in most municipalities, which is problematic, it is interesting to investigate which factors are important for housing construction.

    Current detailed development plans for housing purposes were studied. The detailed development plans that had not been implemented were used as starting material during interviews with relevant actors.

    The purpose of the study was to try to find out what factors affect the fact that detailed development plan land for housing purposes is not built.

    The study's results show that among the factors it is primarily the market situation, high business activity and recession, which affect whether housing construction is going to start or not. There are also factors such as construction law handling times that affect how soon a residential building can get started.

    The conclusion of the study was, among other things, that the market situation seems to be the most influential factor and because the market is governed by profit-dependent players, supply and demand will not always meet. Other conclusions that were drawn were that what is being built is not what is requested and that the building permits take longer than is required by plan- och bygglagen.

  • 2.
    Abrehdary, Majid
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Sjöberg, Lars E.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering. Royal Institute of Technology (KTH), Division of Geodesy and Satellite Positioning, Stockholm, SE-100 44, Sweden.
    Sampietro, D.
    GReD S.r.l., Via Cavour 2, Lomazzo (CO), 22074, Italy.
    Contribution of satellite altimetry in modelling Moho density contrast in oceanic areas2018In: Journal of Applied Geodesy, ISSN 1862-9016, E-ISSN 1862-9024Article in journal (Refereed)
    Abstract [en]

    The determination of the oceanic Moho (or crust-mantle) density contrast derived from seismic acquisitions suffers from severe lack of data in large parts of the oceans, where have not yet been sufficiently covered by such data. In order to overcome this limitation, gravitational field models obtained by means of satellite altimetry missions can be proficiently exploited, as they provide global uniform information with a sufficient accuracy and resolution for such a task. In this article, we estimate a new Moho density contrast model named MDC2018, using the marine gravity field from satellite altimetry in combination with a seismic-based crustal model and Earth's topographic/bathymetric data. The solution is based on the theory leading to Vening Meinesz-Moritz's isostatic model. The study results in a high-accuracy Moho density contrast model with a resolution of 1° × 1° in oceanic areas. The numerical investigations show that the estimated density contrast ranges from 14.2 to 599.7 kg/m3 with a global average of 293 kg/m3. In order to evaluate the accuracy of the MDC2018 model, the result was compared with some published global models, revealing that our altimetric model is able to image rather reliable information in most of the oceanic areas. However, the differences between this model and the published results are most notable along the coastal and polar zones, which are most likely due to that the quality and coverage of the satellite altimetry data are worsened in these regions.

  • 3.
    Ahonen, Patricia
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Heimdal, Karin
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Samordnat planförfarande: en förenkling?2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The coordinated planning procedure regulates how consultation, announcement and review can be simplified and coordinated with a case that is examined according to the Road Act or the Rail Construction Act. A coordinated planning procedure was introduced in the Planning and Building Act on 1 January 2015. Previously, the procedure has been regulated as a simple procedure. The simple procedure was introduced in the new Planning and Building Act in 2011 after investigations and preparatory work found that a simpler planning process is needed to streamline construction and speed up social development. The opportunity for simplification should also help to avoid double work and double testing. In order to apply the procedure, certain requirements are set. If the requirements are met, the municipality can skip consultations and, in some cases, also use the environmental impact assessment that is produced in the road or railways plan. When amending the Road Act and the Railway Construction Act in 2013, the corresponding simplification and coordination provisions were also introduced in these. However, the study shows that the Swedish Transport Administration cannot simplify the consultation in the same way as the municipalities and that it is difficult for the Swedish Transport Administration to make use of an environmental impact assessment that has been produced by the municipality. The study is based on answers from surveys sent out to municipalities and the Swedish Transport Administration as well as interviews. The answers from the surveys show that the knowledge of the procedure is very low both at the municipality and at the Swedish Transport Administration. A few respondents indicate that they have used the procedure and have different views on the advantages and disadvantages of the procedure. From the study we have found that coordinated planning is difficult to apply, which means that it is rarely used. The study shows that more general coordination is used as the parties see advantages in sharing investigations and in some cases also trying to hold joint consultations in order to increase public understanding and avoid double messages. It can be stated that the municipal planning process and the planning process for state infrastructure differ both in process and time, which is the main reason why coordinated planning procedure sounds nice but is difficult to apply.

  • 4.
    Alizadeh-Khameneh, Mohammad Amin
    et al.
    KTH Royal Institute of Technology, Division of Geodesy and Satellite Positioning, Stockholm, Sweden.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Jensen, Anna O.
    KTH Royal Institute of Technology, Division of Geodesy and Satellite Positioning, Stockholm, Sweden.
    Optimization of deformation monitoring networks using finite element strain analysis2018In: Journal of Applied Geodesy, ISSN 1862-9016, E-ISSN 1862-9024, Vol. 2, no 2, p. 187-197Article in journal (Refereed)
    Abstract [en]

    An optimal design of a geodetic network can fulfill the requested precision and reliability of the network, and decrease the expenses of its execution by removing unnecessary observations. The role of an optimal design is highlighted in deformation monitoring network due to the repeatability of these networks. The core design problem is how to define precision and reliability criteria. This paper proposes a solution, where the precision criterion is defined based on the precision of deformation parameters, i. e. precision of strain and differential rotations. A strain analysis can be performed to obtain some information about the possible deformation of a deformable object. In this study, we split an area into a number of three-dimensional finite elements with the help of the Delaunay triangulation and performed the strain analysis on each element. According to the obtained precision of deformation parameters in each element, the precision criterion of displacement detection at each network point is then determined. The developed criterion is implemented to optimize the observations from the Global Positioning System (GPS) in Skåne monitoring network in Sweden. The network was established in 1989 and straddled the Tornquist zone, which is one of the most active faults in southern Sweden. The numerical results show that 17 out of all 21 possible GPS baseline observations are sufficient to detect minimum 3 mm displacement at each network point. © 2018 Walter de Gruyter GmbH, Berlin/Boston.

  • 5.
    Andersen Engstrand, Matilda
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Kommuners uppföljning av åtaganden i exploateringsavtal2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Land development agreement is an agreement for the implementation of a detailed plan that regulates the financial and practical issues required for implementation. The parties involved are the municipality, as a planning authority, and a private property owner who wishes to develop their property, a developer. The Contract Act and the Freedom of Contract are basically at hand, but the contents of the development agreement are regulated to some extent in the Planning and Building Act. The municipality as an authority must also relate to the public law, such as the Local Government Act, the Public Procurement Act and the EU state aid rules.

    The purpose of the study is to investigate to what extent, and with what methods, the municipalities are working on monitoring commitments in development contracts. Material has since been collected through surveys to all of Sweden's municipalities and in-depth interviews with two selected municipalities.

    80 replies were received on the questionnaires. It showed that 68.8% did not consider themselves to have a routine for general follow-up of commitments in land development contracts. The majority of those who considered themselves to have a routine stated "project leader follows up" or "continuous follow-up" as the current routine. On specific issues concerning follow-up of property formation and financial security, the municipalities considered to a greater extent routine for follow-up. Real estate development stated that the municipalities were able to secure by applying for a settlement themselves in cases where it was a municipal matter. Financial security ensures the municipalities primarily by requiring security before signing contracts, or the project manager is responsible for the follow-up.

    With detailed development plans where the property owners build and maintain the publically accessible places, some municipalities felt that there was more to follow up, some that less follow-up takes place.

    The two interviewed municipalities described how the project manager's routine for follow-up can work and that they both work actively with follow-up.

    The conclusion is that some municipalities are actively working on follow-up of commitments, but that there are a lot of shortcomings. Some municipalities do not seem to work actively with the follow-up. Among these municipalities are many of those who write zero or very few agreements annually, but also several municipalities that write many agreements annually.

  • 6.
    Andersson, H. Robert H.
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    de Blanche, Andreas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Flipping the Data Center Network: Increasing East-West Capacity Using Existing Hardware2017In: 2017 IEEE 42nd Conference on Local Computer Networks (LCN), 9-12 Oct. 2017, IEEE, 2017, p. 211-214, article id 8109355Conference paper (Refereed)
    Abstract [en]

    In today's datacenters, there is an increasing demand for more network traffic capacity. The majority of the increase in traffic is internal to the datacenter, i.e., it flows between different servers within the datacenter. This category of traffic is often referred to as east-west traffic and traditional hierarchical architectures are not well equipped to handle this type of traffic. Instead, they are better suited for the north-southbound traffic between hosts and the Internet. One suggested solution for this capacity problem is to adopt a folded CLOS topology, also known as spine-leaf, which often relies on software defined network (SDN) controllers to manage traffic. This paper shows that it is possible to implement a spine-leaf network using commodity-ofthe-shelf switches and thus improve the east-west traffic capacity. This can be obtained using low complexity configuration and edgerouting for load balancing, eliminating the need for a centralized SDN controller.

  • 7.
    Andersson, Henrik
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Bosson, Christoffer
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Landsbygdsutveckling i strandnära lägen: En kartläggande och jämförande studie av hur kommuner och Länsstyrelser tillämpar lagstiftningen2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    2009/2010 a new concept was brought into Environmental code and Planning and Building Act, which was countryside development in areas close to shores (LIS). This amendment was motivated by that areas which have a low degree of exploited land area and high access to seaside areas would get an opportunity to reliefs in coastal protection regulations, in order to be able to offer attractive areas for living and establishing different activities within the municipality. Since the amendment came into force the main responsibility for approval of exceptions from costal protection regulations is on the county. The county administrative board main responsibility is to keep an eye on the granted approvals of the municipalities. The amendments in the Planning and Building Act resulted in the possibility for the municipalities to present areas in with a relief in coastal protection regulations, as a part of the comprehensive plan, an addition to the comprehensive plan or an extensive version for a part of the comprehensive plan.

    The purpose of this study is to investigate and compare how the legislation about LIS is applied, by studying 44 municipalities including the documents of comments from the county administrative board. The first part of the study is the quantitative part which contains collecting and compile information and statistics in which the study will be founded. The study also contains a qualitative part of analyzing the results obtained in the quantitative part.

    Overall the study shows that there is a disagreement between the municipalities and the county administrative board regarding costal protection regulation. The conclusion is based on the results from the study presenting the comments from the county administrative board to the municipalities during the final examine before the comprehensive plan is adopted by the municipal council. The results in the study show a pattern in the most frequent comments from the county administrative board compiled. The most common comment from the county administrative board is that the municipality has not fulfilled the purpose of the legislation about LIS. Furthermore, the municipality has not considered national interests in the municipal areas meant for LIS. The study shows that different political ideology has an influence on the execution of the legislation about LIS in municipalities. The results in the study show that the political ideology has an impact on the numbers of areas which the municipalities present as LIS. As a matter of fact, the impact of political ideology is greater than the impact of geographical similarities between two municipalities, according to the results in the study.

  • 8.
    Andersson, Jennie
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Collby, Ida
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Planprocessen utifrån ett gentrifieringsperspektiv: En studie med gentrifiering i fokus för fyra stadsdelar i Göteborg2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gentrification is a concept for the process of change that occurs in a neighborhood where people with high economic status move into an area that has previously been dominated by people with low socio-economic status. The process takes place step by step and affects, among other things, the economic, social, physical and cultural impression in the district. The concept itself is not well mentioned in urban planning or by politicians. Instead, they choose to use words such as integration in their work as it leaves a positive impression. The gentrification process can eventually give positive effects to a neighborhood if it generates growth and contributes to increased service in the area. However, the negative side of the gentrification process is more talked about. The negative effects are characterized by consequences for the residents in an area where the rents increase and they can no longer afford to live. The reason for the price increase and the fact that people are forced to move can be a consequence of the rebuilding and new construction run by the municipality and developers. The phenomenon occurs worldwide, but due to the extensive degree of development within the City of Gothenburg, the study will be based on the municipality. The purpose of this study is to investigate how the City of Gothenburg relate to the concept of gentrification and to what extent they work with its sanctions when they add new detailed plans for an area. The study is also meant to investigate the municipality's position on the concept as well as whether it is conscious or unconscious decisions that make, which in turn can lead to the re-enactment of the detailed planning area. In order to delimit the study, four areas were chosen in Gothenburg with similar conditions where a new detailed plan has gained legal force and exploitation is either started or completed. A qualitative method was used for reading material and interviews were held with the municipality and an developer to gain insight into the thinking about the design of the detailed plans and the exploitation. After completing the study, we have found that gentrification is a loaded concept, which means that politicians and urban planners also do not want to know it. In connection with the interviews carried out for the study, there was a lack of knowledge about the concept's existence, but a strong belief that their particular project would generate a positive gentrification effect for the area they project. Some interviewees also reported for some type of conscious gentrification when they felt that an increased population and variety of population groups could contribute to something positive despite the possible risk of gentrification in the exploited area.

  • 9.
    Andersson, Jens
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lybratt, Rickard
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Överklagade lantmäteriförrättningar: I Västra Götalands och Hallands län mellan år 2012 och 20172018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study investigates and maps the extent to which decisions taken by the Cadastral authorities have been appealed in Västra Götaland County and Halland County between the years 2012 and 2017, where the years 2013 and 2016 were chosen to be studied at a deeper level. Furthermore, the study investigates differences between KLM and SLM regarding working methods and the proportion of appealed cadastral procedures. The study was conducted by reviewing 321 rulings from the Land and Environment Court, which is all the rulings regarding appealed cadastral procedures in Västra Götaland County and Halland County during the years 2013 and 2016. All 321 rulings were categorized as following; the cadastral measure being appealed, appellant, municipality, the reason for the appeal and the outcome in the Land and Environment Court and appeal to the Land and Environment Court of Appeal. In addition, interviews have been conducted with a judge and a Technical Judge from the Land and Environment Court. Interviews were also made with five current and former surveyors with experience from KLM, SLM or both. The interviews were conducted primarily to investigate differences between working methods at KLM and SLM and to investigate whether this may have any connection with the proportion of appealed cadastral procedures. The result shows that the proportion of appeals has been on average 5 % in Västra Götaland County and 4 % in Halland County between the years 2012 and 2017. The most common cadastral measure being appealed has been property reallotments and facility procedures. Furthermore, cadastral procedure costs has been the most common cause of appeal. In almost 50 % of all the reviewed rulings, the Land and Environment Court chose to establish the decisions made by the Cadastral authorities. In approximately 25 % of the cases, the court chose to change the decisions made by the Cadastral authorities. The result also showed a difference regarding the proportion of appeals between municipalities with KLM (3 %) and municipalities without (5 %). If the statistics are related to the different working methods at SLM and KLM cannot be said with certainty. From the interviews, however, it was found that many had the opinion that personal contact with the interested party and local knowledge is two important factors in order to make a good cadastral procedure. These are things that appear to be more common at KLM.

  • 10.
    Andersson, Jonas
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Thyrsson, Alicia
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Marklov för trädfällning & skogsplantering: Kravets omfattning och utbredning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In community planning, there are many regulations that can be made to control land use and a detail development plan is an instrument that Sweden's municipalities have access to in order to do so. In a detail development plan, the municipality may specify properties that will apply in an area, such as the protection of trees, whish this study is about. To protect trees a plan regulation is required in the plan indicating what is applicable. In the Planning and Building Act 9 chap. 12 § it is stated that the municipality in a detail development plan may decide that a land permit is required for felling trees and for afforestation. An application for a permit to felling trees and / or afforestation shall be sent to the municipality, which will examine whether the application is to be granted or refused. Entering a land permit for felling trees in the detail development plan protects trees that may otherwise be cut down without the municipality's knowledge.

    The survey aims at examining the extent to which the municipalities of Sweden use the opportunity to decide on land permits in a detail development plan. Furthermore, the municipality's motive for the protection of trees is investigated and if it is done otherwise than with the plan regulation, and whether there has been any change in how the municipalities regulate trees in 2017 compared to 1990, when the detail development plan had recently been introduced. This has been done with both qualitative and quantitative methods to get a versatile and complete study.

    The results show that the municipalities used the plan regulation for land permit for felling trees in 60 of the detail development plans in 2017. To ensure protection of trees municipalities use other methods than land permit, for example a Plan regulation to protect trees. The motives given by the municipalities to protect trees vary widely and there are ecological, social and aesthetic reasons. In the comparison of detail development plans from 2017 and 1990, differences have been observed. More plans in 2017 with land permit for felling trees have been observed as well as more and more varied motivations. Plan regulation about afforestation has been found only once in a total of 1 353 detail development plans.

  • 11.
    Andersson, Sara
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Mänsklig faktor: hur kan man få den svagaste länken inom IT-säkerhet starkare?2018Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    In today´s IT environments, the role of the users becomes more important. In 2016 there were 200,000 crimes in Sweden that could be linked to social engineering attacks. These attacks are targeting the users and it is therefore important that users are aware of what they look like. This report is conducted in cooperation with a municipality in Västergötland, Sweden, and investigate four different methods to use when sharing IT information to their users. The methods differ not only in implementation but also in difficulty in the choice of words and expressions. The first method is a document of information taken from the municipality´s intranet. The second is also a document but is rewritten to simplify for the users. The third method is a video presentation and the fourth was made as a lecture with the possibility of interaction between the lecturer and the users. To evaluate these four methods two surveys were conducted. The first survey was performed before the users received IT information to create a baseline. After one and a half month the second survey was made. The surveys are compared to see how much the users remember and which method was most effective. The results indicate that the information on the municipality´s intranet is difficult to understand for the users. The other three methods provide a greater positive change in the user’s questionnaire response, indicating that users need a different form and structure when information is to be provided for them.

  • 12.
    Andersson, Sara
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Karlsson, Madeleine
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    802.1X, Cisco ISE och FortiAuthenticator: Autentiseringsmetoder för Ethernet i ett kommunalt nätverk2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    When people connect to the network in the main building of a municipality in Västra Götaland they get an IP address from their administrative network.

    The municipality want to be able to separate the staff from the guests. In the current situation, their older servers are on the administrative network and therefore represents a security risk, as some of the servers do not have a firewall in between that can stop malicious traffic.

    The report will include the possible security risks that the municipality in the current situation can be exposed to and therefore three different authentication methods will be compared. The authentication methods that will be compared in the report is FortiAuthenticator, Cisco ISE and 802.1X with RADIUS. The reason these have been selected are because the municipality in the current situation is using FortiGate firewalls, Cisco devices and RADIUS. The report also includes dynamic VLAN as this can be used with 802.1X.

    The result that has been developed is that FortiAuthenticator and Cisco ISE has many similarities, however there are a few things that set them apart. In the implementation of 802.1X there are advantages and disadvantages to be considered. However, all three methods work well in the municipal network.

  • 13.
    Andlovic, Mihael
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    How real-world IP-distribution affects load balancing2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This essay looks at how IP addresses on the last octet are distributed and how they are balanced by different load balancer algorithms. We collected the data from a data center in Sweden to get real data. The IP addresses we collected were used with a load balancer using IP source algorithms. We used 4 different algorithms in different scenarios: the entire IP address, the first 3 octets, and the last octet with and without hash between two to five links/servers. The results were that the efficiency of the algorithm depends on the setup that is being used. Each of these algorithms did not have an even distribution, when comparing between two to five links/servers. The best overall distribution that did not have any weaknesses compared to the other algorithms was Nginx that uses the Bob Jenkins hash algorithm.

  • 14.
    Arbo, Thomas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    YubiKey: Utvärdering av tvåfaktorsautentisering2019Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    YubiKey is a small hardware method of authentication, designed to authenticate a user on various network-based platforms such as Google, Dropbox, Facebook and Twitter.

    In the first part of this paper, the underlying technology of the YubiKey, such as the one-time password protocol (OTP) and the Universal 2nd Factor standard, is further described, as well as the approach of the tests to examine how practical and secure the method itself is, but also examines its ease of use. These tests were performed on the platforms Google Account, Facebook, Dropbox and Twitter platforms. The YubiKey is also compared to other methods in relation to the phishing, malware, password guessing, man-in-the-middle and shoulder surfing attacks.

    The purpose of the comparison was to see if YubiKey protects against these attacks, compared to other methods, thus investigating its security. A later part presents the results of the tests, but also compares YubiKey with other methods in the market, and examines the recovery of a stolen och lost Yubikey. These tests show the simplicity of the method, its ease of use and how practical the method is.

    The comparison clearly shows that YubiKey is a very safe method, which resists common threats to the user side. The simulation of the recovery process further attests to its ease of use and ease of handling, even with lost or stolen key.

  • 15.
    Bejbom, David
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Mätmetodik vid interiörmätning – kan den effektiviseras genom vidareutvecklad EDM-teknik?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study examines surveying with indoor surveying as main focus. Indoor surveying is used to produce plans of an existing building that is being conversed to e.g. dwellings. The study evaluates reflectorless and prism measurement with total station. The purpose with the study is to identify the problems that occur when measured surveying is conducted and establish adequate surveying methods with regards to efficiency and quality. It will also be examined if a further development of the electromagnetic distance measurement (EDM) technique will enable for reflectorless measuring to phase out the use of prism. To put the purpose into practice a few question formulations were established:  What objects are today problematic when conducting indoor surveying?  Which are the most adequate methods when measuring the objects identified above with regards to efficiency and uncertainty?  What are the ratio between reflectorless measuring made with different developed EDM technique? A number of qualitative interviews with surveyors were carried out to identify problematic objects and surveying methods used today. Together with earlier studies in the field, those interviews was the basis for the design of the quantitative field examination. The problematic areas examined were; large incidence angle, outside corner, inside corner and circular objects. Each of the reflectorless measurements were carried out by two instruments using different developed EDM technique, which enabled a comparison. Furthermore prism measurement were conducted since that is the leading method this day. The examination showed that prism measurement had the largest amount of results meeting the requirement of an enlarged uncertainty < 10 mm. Prism measurement fulfilled the requirement in 34 out of 46 of the scenarios, compared to 38 out of 54 when using reflectorless measuring with the newer total station. The examination also showed that the instrument using a newer EDM technic performed better in 50 out of 54 scenarios. Hence the conclusion were made that a further development of the EDM technique may enable a phase out of the use of prism on a wider scale. To be able to make correct choices of surveying methods, the final products requirements, which instrument that are being used and the shape and placing of objects need to be taken into consideration.

  • 16.
    Bengtsson, Robert
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Claesson, Rickard
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Att designa ett kostnadseffektivt nätverk för det lilla företaget2018Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This paper goes through the process of designing a corporate network from scratch. The work clarifies some concepts in network design, how a simple requirement specification can look and how it is used in the process of creating a network that meets the customer's needs.

  • 17.
    Bergstrand, Andrea
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Säkerhetsbilden mot den uppkopplade bilen: En analys om säkerhet och hot i fordons trådlösa kommunikation2019Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Connected vehicles are being developed extensively, and in 2019, vehicle manufacturers and transport companies will start equipping vehicles and roads with wireless communication around Europe. This will increase safety and streamline the traffic by allowing drivers to be warned of what they have not yet seen as vehicles around the corner, queuing, slipping, collision and road work. However, accidents involving connected vehicles have occurred recently, which has created uncertainty regarding its safety. Great demands are placed on its safety when connected vehicles will increase significantly on the roads.

    The study aims to carry out a safety assessment against the connected car with the aim of investigating potential threats and risks in vehicle wireless communication, what is required for the technology to be considered safe and reviewing various safety solutions developed.

  • 18.
    Berntsson, Jenny
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    A study on the quality of the NKG2015 geoid model over the Nordic countries2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The NKG2015 (Nordic Geodetic Commission) geoid model is the most recent official geoid model over the Nordic countries. There has been no previous research published on the quality of this model, therefore, this study may be a valuable contribution to the research in this area. It is important to be aware of the limitations and quality of the geoid model used when measuring heights. If the quality of the geoid is not known, the quality of the measured heights will also be uncertain. This might cause problems when the measured heights are used in projects where great precision is vital.

    Measured GNSS (Global Navigation Satellite Systems)/levelling data has been compared to the computed geoid heights from the NKG2015 geoid model at the corresponding points to investigate the quality of this model. The misclosures between the geoid height, obtained from the GNSS/levelling data and the geoid heights from the NKG2015 geoid model have been analysed by statistical methods. The normality of the misclosures is tested, and the analysis is performed on unfiltered and filtered misclosures with confidence intervals (CIs) of 95% and 99.7% to remove probable outliers. Trends in the misclosures are removed with a least-squares detrending method.

    The result of the study shows that filtering the misclosures generally makes them more normally distributed, but this is not the case for all countries. Detrending the misclosures improves the normality in most cases. In this process, a corrective surface with a specified number of parameters is fitted to the misclosures to remove trends. The topography of each country is very important when deciding which corrective surface that should be used in the detrending process. Countries with rough topography such as Norway has greater uncertainty in its heights and needs a corrective surface with more parameters than flatter countries such as Denmark. There are some estimates for the errors for the GNSS/levelling data which are not all in agreement with the misclosures. The GNSS/levelling error in Finland is greater than it should be.

    The given, estimated errors of the NKG2015 geoid model are 10 mm for Sweden and Denmark, 22 mm for Norway and 12 mm for Finland. These errors are reasonable, but not in perfect agreement with the given errors of the GNSS/levelling measurements in relation to the misclosures. Based on the assumption that the GNSS/levelling errors are correct, confidence intervals of the geoid error can be estimated. These estimated intervals are 0-6.5mm for Sweden, 1.8-5.2mm for Denmark, 14.8-17.7mm for Norway and 0-0mm for Finland. The confidence interval for Finland is not realistic because it is based on the assumption that the GNSS/levelling error is correct.

  • 19.
    Bertilsson, Alexander
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Sandberg, Joel
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Jämförelse av två VPN lösningar2018Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This thesis is about comparing two different virtual private network (VPN) solutions. One of them is OpenVPN running on a single-board computer called Raspberry pi. The other one is Cisco AnyConnect that runs on a Cisco firewall called ASA 5510. To compare and find out which one of the solutions that worked best, we chose to use three parameters: CPU usage under high load of UDP streams which were sent in a server-client mode over the solutions, the variation of the delay in a connection under same load namely UDP jitter, and how much data loss occurred at the same amount of load. We chose to use Jperf as measurement tool for the values we compared, the measurements occurred both during and after the transmission of traffic in the private tunnel. The software Jperf was used to create a UDP stream with 100 Mbit/s on different packet sizes, the same method was performed on both solutions. In the result, it emerged that the solution with a Cisco ASA 5510 was the better option in terms of the parameters we measured. The ASA had lower CPU usage during the transmission of traffic, the UDP jitter was slightly higher than the other solution, but the packet loss was much lower in all measurements. Based on the results is the Raspberry Pi a quite good solution considering the size and price of the unit. It can handle big sized packets in terms of CPU, jitter and data loss. On the contrary, traffic with smaller packet sizes it has some problems with both CPU usage and packet loss. This leads to poor transmission of traffic with small packet sizes, for instance IP telephony. [1] The best solution considering the parameters we chose to use is the Cisco ASA 5510 with AnyConnect. It performed better in two cases out of our three tests.

  • 20.
    Borg, Louise
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Ekosystemtjänster i kommunal planering2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In 2018 the meaning of biodiversity and the value of ecosystem services should be general knowledge and integrated into economical standpoints, political considerations and other decisions where relevant and reasonable. This is one of the milestone targets that the Swedish government decided in 2012. We know today that only parts of this target will be reached. This study includes a survey regarding the concept of ecosystem service in Sweden, all the local authority comprehensive planning, and an examination of three housing projects in Stockholm’s county where ecosystem services were the focal point during the comprehensive planning. In the first part of the study, which concentrates on surveying the concept of ecosystem services, it can be shown that 116 of 290 municipalities have been using the concept in their local authority comprehensive planning. Furthermore, the concept is used more often than not during the last three years in local authority comprehensive planning. In the second part of the study the outline planning was examined, plan handlings and implementation contracts from projects in Täby, Nacka and Haninge municipality. The research was based on text analysis and on-site inspection. The results from the research showed that the municipalities have a high ambition regarding working with ecosystem services, and that there exist a correlation between the visions in the local authority comprehensive planning and regulations in the detailed developed plan. In the agreement the developers are bound to work according to implementation contracts and sustainability program which regulate the considerations of ecosystem services. The concept of ecosystem services is used to show which benefits we humans receive from nature’s work. We are dependent on continual ecosystem services, which are also essential to the public health and wellbeing. Joint effort and a considerate use of ecosystem services is needed to keep them intact. It can result in large profit for society to preserve, develop and recreate nature and green areas in population centers. To integrate ecosystem services in the physical planning is a step in the right direction. The local authority comprehensive planning show the direction for the municipality’s community planning, and the outline of the future physical structure, it also serves to guide upcoming detailed development plans and building acts. The local authority comprehensive planning plays a key part in the ecosystem services future, since its importance can be illustrated within. To reach the visions of the local authority comprehensive planning and the opportunity to actualize it in the detailed development plan is required. To secure the continued functionality of the ecosystem services, a clear and purposive legislation is required. An increase in knowledge and awareness of ecosystem services is essential, and everyone must see their part in the in our common responsibility and work toward a sustainable society.

  • 21.
    Carlson, Freddie
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Zurowetz, Sebastian
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Kommuners förhållningssätt till regeln om reduktion av bygglovsavgiften: en studie av fyra kommuner inom Västra Götaland2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Planning and Building act (PBL) was rewritten in 2011. A new requirement was added for the local authorities to handle building permits within ten weeks from when the applications were completed. However there were no sanctions added against the local authorities if they were to exceed the deadline of ten weeks. Several investigations performed by, for example Boverket, show that the local authorities have difficulties meeting the deadline. JO has several times, since the readjustment in 2011, complained to local authorities of their unreasonable processing time.

    In 2016 the government gave Boverket an assignment to investigate if the local authorities are meeting the deadlines and to propose a sanction system for the building committees, if they exceed the ten weeks. The purpose of the assignment was to improve the local authorities' processing time and to make the building process more effective. The report from Boverket showed that 81 percent of the local authorities handle a majority of the building permits within the deadline and that the processing time has improved every year since the Planning and Building act was rewritten in 2011. It was stated in the report from Boverket, that a reduction of the building permit fee was the most suitable penalty to use against the local authorities for a time violation.

    The reduction of the building permit fee was introduced in PBL on the first of January 2019, and was stated in paragraph 12:8 a. The penalty is structured so that every started week that exceeds the deadline, the building permit fee will be reduced by a fifth. In this study it has been analysed what impact the rule has had on four local authorities and how they interpret the rule. The study has been limited to and is only focused on building permits that are outside of the detailed plan, with minor deviance from the detailed plan and building permits for major buildings. The study is based on interviews with the manager in the department of building permit in four different local authorities located in Västra Götaland. Three of the local authorities were chosen based on size of population and the fourth was chosen to represent a local authority that has major seasonal accommodation. Before every interview the interviewees have been given an interview guide, and during the interviews the same basic questions have been asked with an opportunity to ask in-depth follow-up questions.

    The result showed that 12:8 a will not have a significant impact on the local authorities and therefore will not result in a more effective building process. The reason for this is that the new regulation is only a small part in the bigger picture and has a lack of deadlines in other parts of the building process. This will lead to local authorities simply moving resources to the area that has a deadline, while other steps of the process will not be as prioritized. The conclusion from these findings show that the whole building process should be looked over. The rules within PBL should be better aligned with each other and also with other laws. The guidance that Boverket gives to the local authorities should also be clearer, since local authorities can interpret the law differently. Overall, the 12:8 a paragraph will not have a big impact on the building process. The purpose of PBL on a simpler Planning and Building act continues to be sidestepped.

  • 22.
    de Blanche, Andreas
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Node Sharing for Increased Throughput and Shorter Runtimes: an Industrial Co-Scheduling Case Study2018In: Proceedings of the 3rd Workshop on Co-Scheduling of HPC Applications (COSH 2018): Held together with HiPEAC 2018 / [ed] Trinitis, Carsten; Weidendorfer, Josef, 2018, p. 15-20Conference paper (Refereed)
    Abstract [en]

    The allocation of jobs to nodes and cores in industrial clusters is often based on queue-system standard settings, guesses or perceived fairness between different users and projects. Unfortunately, hard empirical data is often lacking and jobs are scheduled and co-scheduled for no apparent reason. In this case-study, we evaluate the performance impact of co-scheduling jobs using three types of applications and an existing 450+ node cluster at a company doing large-scale parallel industrial simulations. We measure the speedup when co-scheduling two applications together, sharing two nodes, compared to running the applications on separate nodes. Our results and analyses show that by enabling co-scheduling we improve performance in the order of 20% both in throughput and in execution times, and improve the execution times even more if the cluster is running with low utilization. We also find that a simple reconfiguration of the number of threads used in one of the applications can lead to a performance increase of 35-48% showing that there is a potentially large performance increase to gain by changing current practice in industry.

  • 23.
    Engblom, Tove
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Gunnarsson, Lisa
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lovet på landet: En rättsdogmatisk studie av 9 kap. 6 § PBL2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When the older planning and building act was replaced in 2011 by todays planning and building act, the paragraph regulating permits exempt buildings actions received some linguistic updates. The updates where intended to simplify and update the interpretation. Any changes in the countryside in how this was supposed to be interpreted was not intended. This thesis examines how multiple Swedish municipalities interpret the permits exempt buildings according to 9 chap. 6 § planning and building act. The examination was done with a survey sent to all Swedish municipalities, which was then put together and the results where compared. To be able to decide if the municipalities have been making correct interpretations this thesis have also made a thorough legal examination of the law and preliminary work.

    9 chap. 6 § planning and building act is a complicated paragraph and cannot be interpreted without reading the preparatory work. Unfortunately, just reading the propositions to the planning and building act is not enough. The preparatory work for older planning and building act must also be read to fully grasp the meaning of the law. The paragraph has gone through multiple updates since 1987, therefor the information has been spread out.

    The permits exempt buildings in this paragraph is aimed at property owners owning houses with one or two families in the countryside that want to erect a small extension for the house or a complimentary building adjacent to the main building. The condition is that there is a house on the property and that the building is of a complementary nature to not dominate over the actual main house. The property owner does not need to report to or consult with the municipality but is rather supposed to judge if the rules are applicable for them self.T

    hat the average citizen, without basic legal education, is supposed to be able to interpret a complicated paragraph like this is troublesome. The consequence of a misjudgement is expensive. Unfortunately, there is not a lot of guidance to be had from the municipalities since our survey shows that almost all Building Department are making incorrect decisions based on interpreting the paragraph incorrectly.

    This thesis shines a light on the problem with assigning a complicated paragraph to be interpreted by the property owners. Furthermore, allowing the municipalities to make their own regulations regarding the interpretation of the law, without accountability to superior government agencies does not make the problems fewer. Our conclusion with this thesis results in that better guidance and stricter demands on the municipalities must be enacted to not place too big of a responsibility on the individual citizen.

  • 24.
    Eriksson, Kevin
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Lunde, Jesper
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Teknikstudie över olika laddningstekniker för elfordon2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Electric vehicles are on a strong rise with increasing sales and larger infrastructure every year. For a fast-growing industry like electric vehicles, it is interesting to look at how they are charged as this affects all owners of electric vehicles. The commercial technologies for electric vehicle charging today are conductive and have been standardized. However, several different standards exist, partly competing with each other. The report describes the major standards of IEC, CCS, CHAdeMO and GB/T, in addition to these, there is also the car manufacturer Tesla with its own standard. The thesis takes a closer look at some development projects to see in which directions the technology is developing. Among other things, conductive transmission via rail in or on the road and transmission by wires above the road, but also upgrading of existing standards. Inductive charging projects are further investigated with static inductive charging stations and dynamic inductive charging while driving. The thesis investigates dynamic inductive charging in deeper detail. There is a lot of research and projects going on, but there are still many problems to solve in order to commercialize the technology. The advantage of inductive charging is that it can be wireless and when the vehicle is charged while driving, fewer stops are required to charge. The technology, on the other hand, has some efficiency issues that can vary greatly depending on how the vehicle is aligned towards the transfer coil. Communication to pay for charging, among other things, is still early in the development, as a very high communication speed is required when charging during travel. The writers view is that the major development and expansion will occur in inductive transmission as well as upgrading of the existing conductive standards. Standardization of the upcoming technologies is considered important in order to avoid creating many incompatible technologies on the roads. Work on standardization of inductive transmission is in progress but is not yet complete.

  • 25.
    Eriksson, Monica
    et al.
    University West, Department of Health Sciences, Section for health promotion and care sciences.
    Alsén, Pia
    University West, Department of Health Sciences, Section for nursing - graduate level.
    Lycke, Liselott
    University West, Department of Engineering Science.
    Tano, Ingrid
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Aronsson, Gunnar
    Stockholms universitet, Stockholm, Sverige.
    ARK: modell för att systematiskt arbeta med hållbart arbetsliv inom universitet och högskola (UoH)2018In: FALF 2018 - program och abstraktbok / [ed] Per Lindberg, Gävle: University Press , 2018, p. 123-123Conference paper (Refereed)
    Abstract [sv]

    Bakgrund

    Hållbart arbetsliv är idag ledord för arbetslivets förändrade villkor. Inom UoH i Sverige fanns i slutet av 2017 omkring 75 000 anställda varav ca 35 000 inom forskning och undervisning (UKÄ, 2017). Det är en sektor med stor betydelse för samhällsutvecklingen i Sverige. Arbetsmiljön inom sektorn ställer särskilda krav på personalen. Förvånansvärt få studier har gjorts i Sverige om arbetsmiljön för personal inom UoH. Med förebild från Norge implementeras nu för första gången i Sverige en forskningsbaserad (krav-resurs-modellen) och sektorsspecifik ny modell för att systematiskt arbeta med arbetsmiljön, den s.k. Ark-modellen (arbeidsmiljø- og klimaundersøkelser, se figur) vid Högskolan Väst. Arbetsmiljöverkets föreskrift 2015:4 betonar den organisatoriska och sociala arbetsmiljön, vilket väl tillgodoses i denna modell.

    Syfte

    Att systematiskt och långsiktigt arbeta med arbetsmiljön ur ett främjande, förebyggande och rehabiliterande perspektiv på såväl individ- som organisatorisk nivå för att utveckla förhållanden som bidrar till ett hållbart arbetsliv.

    Metod

    Genom KIWEST (Knowledge Intensive Work Environment Survey Target) kartläggs arbetsmiljön utifrån 28 olika dimensioner. Kategorier som belyses är t.ex. sociala, uppgiftsbaserade och organisatoriska resurser samt jobbkrav och tillhörighet till jobbet. Organisatoriska förhållanden mäts med FaktaARK 1 medan genomförda insatser mäts med FaktaARK 2.

    Resultat

    KIWEST sändes till all personal med 20 % anställning eller mer. Utav 539 tillfrågade personer svarade 376, vilket ger en svarsfrekvens på 69,8 %. Resultatet visar att specifikt för sektorn är upplevelsen av tidspress samtidigt som arbetet upplevs som meningsfullt och viktigt. Nu följer analyser, planering, genomförande och utvärdering av insatser på olika nivåer inom högskolan. KIWEST-formuläret sänds till personalen med 3-års intervall. I förbättringsarbetet ingår även att granska och utvärdera genomförandet, därvid ingår även metodutveckling. Förbättringsarbetet sätts in i ett större organisatoriskt perspektiv och är en naturlig del i kvalitetssäkringsprocessen och ledningssystemet. ARK-processen förväntas bidra till teoriutveckling av krav- och resursmodellen samt öka kunskapen om arbetsmiljön inom UoH.

  • 26.
    Eriksson, Tommie
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Damfelt, Christoffer
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Increasing Simulation Performance: Experimental tests of bottlenecks and scalability of LS-DYNA on Tetra Pak HPC-clusters2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Larger companies working with simulations and computing resources, require a lot of resources to execute their jobs. To make simulations less performance heavy, High-Performance Computing (HPC) is often used. HPC clusters implements a parallel algorithm over multiple nodes to speed up and utilize many computers, with this, large simulations that require a lot of resources will not take extensive amounts of time to finish.

    Large simulations can be performance heavy and time consuming and thus cost a lot of money if extra computing resources from outsourcing are needed. Optimizing HPC clusters can reduce extra costs while also decreasing the time it takes to execute jobs.

    With the cooperation of Packaging Material (PM), which is a business unit at Tetra Pak in Lund, Sweden, this thesis aims to understand Multi Parallel Processing (MPP) solvers, investigate Tetra Pak's HPC cluster to confirm that the right hardware and software is available and used as well as selecting and running representative simulation models and runtime parameters commonly used by PM, with the goal of optimizing their HPC clusters.

    Results given in this thesis are based on multiple tests which show that there are improvements that can be made, in both hardware and software. According to the findings in this thesis using newer versions and updated instructions for the processors a performance increase up to 17% is achievable.

  • 27.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Elastic thickness determination based on Vening Meinesz-Moritz and flexural theories of isostasy2018In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 213, no 3, p. 1682-1692Article in journal (Refereed)
    Abstract [en]

    Elastic thickness (Te) is one of mechanical properties of the Earth's lithosphere. The lithosphere is assumed to be a thin elastic shell, which is bended under the topographic, bathymetric and sediment loads on. The flexure of this elastic shell depends on its thickness or Te. Those shells having larger Te flex less. In this paper, a forward computational method is presented based on the Vening Meinesz–Moritz (VMM) and flexural theories of isostasy. Two Moho flexure models are determined using these theories, considering effects of surface and subsurface loads. Different values are selected for Te in the flexural method to see by which one, the closest Moho flexure to that of the VMM is achieved. The effects of topographic/bathymetric, sediments and crustal crystalline masses, and laterally variable upper mantle density, Young's modulus and Poisson's ratio are considered in whole computational process. Our mathematical derivations are based on spherical harmonics, which can be used to estimate Te at any single point, meaning that there is no edge effect in the method. However, the Te map needs to be filtered to remove noise at some points. A median filter with a window size of 5° × 5° and overlap of 4° works well for this purpose. The method is applied to estimate Te over South America using the data of CRUST1.0 and a global gravity model.

  • 28.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Numerical aspects of EGM08-based geoid computations in Fennoscandia regarding the applied reference surface and error propagation2013In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 96, p. 28-32Article in journal (Refereed)
    Abstract [en]

    So far the recent Earth's gravity model, EGM08, has been successfully applied for different geophysical and geodetic purposes. In this paper, we show that the computation of geoid and gravity anomaly on the reference ellipsoid is of essential importance but error propagation of EGM08 on this surface is not successful due to downward continuation of the errors. Also we illustrate that some artefacts appear in the computed geoid and gravity anomaly to lower degree and order than 2190. This means that the role of higher degree harmonics than 2160 is to remove these artefacts from the results. Consequently, EGM08 must be always used to degree and order 2190 to avoid the numerical problems. © 2013 Elsevier B.V.

  • 29.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    On the approximations in formulation of the Vening Meinesz-Moritz theory of isostasy2017In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 210, no 1, p. 500-508Article in journal (Refereed)
    Abstract [en]

    Different approximations are used in Moho modelling based on isostatic theories. The well-known approximation is considering a plate shell model for isostatic equilibrium, which is an oversimplified assumption for the Earth’s crust. Considering a spherical shellmodel, as used in the Vening Meinesz-Moritz (VMM) theory, is a more realistic assumption, but it suffers from different types of mathematical approximations. In this paper, the idea is to investigate such approximations and present their magnitudes and locations all over the globe. Furthermore, we show that the mathematical model of Moho depth according to the VMM principle can be simplified to that of the plate shell model after four approximations. Linearisation of the binomial term involving the topographic/bathymetric heights is sufficient as long as their spherical harmonic expansion is limited to degree and order 180. The impact of the higher order terms is less than 2 km. The Taylor expansion of the binomial term involving the Moho depth (T) up to second order with the assumption of T-2 = TT0, T-0 is the mean compensation depth, improves this approximation further by up to 4 km over continents. This approximation has a significant role in Moho modelling over continents; otherwise, loss of frequency occurs in the Moho solution. On the other hand, the linear approximation performs better over oceans and considering higher order terms creates unrealistic frequencies reaching to a magnitude of 5 km in the Moho solution. Involving gravity data according to the VMM principle influences the Moho depth significantly up to 15 km in some areas.

  • 30.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Ashargie, Andenet
    Bedada, Tulu B.
    Regional recovery of gravity anomaly from the inversion of diagonal components of GOCE gravitational tensor: A Case Study in Ethiopia, Artificial Satellites2018In: Artificial Satellites : he Journal of Space Research Centre of Polish Academy of Sciences, E-ISSN 2083-6104, Vol. 53, no 2, p. 55-74Article in journal (Refereed)
    Abstract [en]

    The tensor of gravitation is traceless as the gravitational field of the Earth is harmonic outside the Earth's surface. Therefore, summation of the 2nd-order horizontal derivatives on its diagonal components should be equal to the radial one but with the opposite sign. The gravity field can be recovered locally from either of them, or even their combination. Here, we use the in-orbit diagonal components of the gravitational tensor measured by the gravity field and steady stateocean circulation explorer (GOCE) mission for recovering gravity anomaly with a resolution of 1°×1° at sea level in Ethiopia. In order to solve the system of equations, derived after discretisation of integral equations, the Tikhonov regularisation is applied and the bias of thi sregularisation is estimated and removed from the estimated gravity anomalies. The errors of the anomalies are estimated and their significance of recovery from these diagonal components is investigated. Statistically, the difference between the recovered anomalies from each scenario isnot significant comparing to their errors. However, their joint inversion of the diagonal components improved the solution by about 1 mGal. Furthermore, the inversion processes arebetter stabilised when using errors of the input data compared with its exclusion, but at the penalty of degradation in accuracy of the estimates.

  • 31.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Ebadi, Sahar
    K.N.Toosi University of Technology, Tehran, Iran.
    A strategy to calibrate errors of Earth gravity models2014In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 103, no April, p. 215-220Article in journal (Refereed)
    Abstract [en]

    In this paper, three independent Earth gravity models (EGMs) ofGO_CONS_GCF_2_TIM_R4, AIUB-GRACE03S and ULux_CHAMP2013s are combined to degree and order 120. The geoid models of these EGMs are computed and compared with the Global Positioning System (GPS) and levelling data over Fennoscandia. We found that the simple mean of these geoid models is closer to the GPS/levelling data than their weighted mean. This means that errors of the EGMs are not properly estimated as they are used in the weighted mean solution. We develop a method based on solving a nonlinear condition adjustment model to calibrate the errors so that the result of weighted mean becomes the same as that of the simple mean. Numerical results show slight changes in the errors of GRACE03S but large ones in those of GO_CONS_GCF_2_TIM_R4 and ULux_CHAMP2013s. Furthermore, the weighted mean solution considering the calibrated errors and some additional constraints is better than GOCO03S to degree and order 120 over Fennoscandia.

  • 32.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Johansson, Filippa
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Karlsson, Lenita
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Horemuz, Milan
    Royal Institute of Technology, Stockholm, Sweden.
    A case study on displacement analysis of Vasa warship2018In: Journal of Geodetic Science, ISSN 2081-9919, E-ISSN 2081-9943, Vol. 8, no 1, p. 43-54Article in journal (Refereed)
    Abstract [en]

    Monitoring deformation of man-made structures is very important to prevent them from a risk of collapse and save lives. Such a process is also used for monitoring change in historical objects, which are deforming continuously with time. An example of this is the Vasa warship, which was under water for about 300 years. The ship was raised from the bottom of the sea and is kept in the Vasa museum in Stockholm. A geodetic network with points on the museum building and the ship's body has been established and measured for 12 years for monitoring the ship's deformation. The coordinate time series of each point on the ship and their uncertainties have been estimated epoch-wisely. In this paper, our goal is to statistically analyse the ship's hull movements. By fitting a quadratic polynomial to the coordinate time series of each point of the hull, its acceleration and velocity are estimated. In addition, their significance is tested by comparing them with their respective estimated errors after the fitting. Our numerical investigations show that the backside of the ship, having highest elevation and slope, has moved vertically faster than the other places by a velocity and an acceleration of about 2 mm/year and 0.1 mm/year2, respectively and this part of the ship is the weakest with a higher risk of collapse. The central parts of the ship are more stable as the ship hull is almost vertical and closer to the floor. Generally, the hull is moving towards its port and downwards

  • 33.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Pitonak, Martin
    University of West Bohemia, NTIS - The New Technologies for the Information Society, Faculty of Applied Sciences, Pilsen, Czech Republic.
    Tenzer, Robert
    Hong Kong Polytechnic University, Department of Land Surveying and Geo-Informatics, Hong Kong.
    Lithospheric elastic thickness estimates in central Eurasia2019In: Terrestrial, Atmospheric and Oceanic Science, ISSN 1017-0839, E-ISSN 2223-8964, Vol. 30, no 1, p. 73-84Article in journal (Refereed)
    Abstract [en]

    We estimate the elastic thickness of a continental lithosphere by using two approaches that combine the Vening Meinesz-Moritz (VMM) regional isostatic principle with isostatic flexure models formulated based on solving flexural differential equations for a thin elastic shell with and without considering a shell curvature. To model the response of the lithosphere on a load more realistically, we also consider lithospheric density heterogeneities. Resulting expressions describe a functional relation between gravity field quantities and mechanical properties of the lithosphere, namely Young’s modulus and Poisson’s ratio that are computed from seismic velocity models in prior of estimating the lithospheric elastic thickness. Our numerical study in central Eurasia reveals that both results have a similar spatial pattern, despite exhibiting also some large localized differences due to disregarding the shell curvature. Results show that cratonic formations of North China and Tarim Cratons, Turan Platform as well as parts of Siberian Craton are characterized by the maximum lithospheric elastic thickness. Indian Craton, on the other hand, is not clearly manifested. Minima of the elastic thickness typically correspond with locations of active continental tectonic margins, major orogens (Tibet, Himalaya and parts of Central Asian Orogenic Belt) and an extended continental crust. These findings generally support the hypothesis that tectonically active zones and orogens have a relatively small lithospheric strength, resulting in a significant respond of the lithosphere on various tectonic loads, compared to a large lithospheric strength of cratonic formations.

  • 34.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Pitoňák, Martin
    University of West Bohemia, NTIS-The New Technologies for the Information Society, Faculty of Applied Sciences, Pilsen, Czech Republic.
    Elastic Thickness Determination from on-orbit GOCE Data and CRUST1.02019In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 176, no 2, p. 685-696Article in journal (Refereed)
    Abstract [en]

    Elastic thickness (Te) is a parameter representing the lithospheric strength with respect to the loading. Those places, having large values of elastic thickness, flexes less. In this paper, the on-orbit measured gravitational gradients of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission are used for determining the elastic thickness over Africa. A forward computational method is developed based on the Vening Meinesz-Moritz (VMM) and flexural theories of isostasy to find a mathematical relation between the second-order derivative of the Earth’s gravity field measured by the GOCE satellite and mechanical properties of the lithosphere. The loading of topography and bathymetry, sediments and crystalline masses are computed from CRUST1.0, in addition to estimates of laterally-variable density of the upper mantle, Young’s modulus and Poisson’s ratio. The second-order radial derivatives of the gravitational potential are synthesised from the crustal model and different a priori values of elastic thickness to find which one matches the GOCE on-orbit gradient. This method is developed in terms of spherical harmonics and performed at any point along the GOCE orbit without using any planar approximation. Our map of Te over Africa shows that the intra-continental hotspots and volcanoes, such as Ahaggar, Tibesti, Darfur, Cameroon volcanic line and Libya are connected by corridors of low Te. The high values of Te are mainly associated with the cratonic areas of Congo, Chad and the Western African basin.

  • 35.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Steinberger, Bernhard
    Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, Germany & Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Postboks 1028 Blindern, Oslo, Norway.
    Tenzer, Robert
    Hong Kong Polytechnic University, Department of Land Surveying and Geo-Informatics, 11 Yuk Chai Rd, Hung Hom, Hong Kong.
    Tassara, Andrés
    Universidad de Concepción, Departamento de Ciencias de la Tierra, Facultad de Ciencias Químicas, Victor Lamas 1290, Concepción, Chile.
    Comparison of gravimetric and mantle flow solutions for sub-lithopsheric stress modeling and their combination2018In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 213, no 2, p. 1013-1028Article in journal (Refereed)
    Abstract [en]

    Based on Hager and O’Connell’s solution to mantle flow equations, the stresses induced by mantle convection are determined using the density and viscosity structure in addition to topographic data and a plate velocity model. The solution to mantle flow equations requires the knowledge of mantle properties that are typically retrieved from seismic information. Large parts of the world are, however, not yet covered sufficiently by seismic surveys. An alternative method of modeling the stress field was introduced by Runcorn. He formulated a direct relation between the stress field and gravity data, while adopting several assumptions, particularly disregarding the toroidal mantle flow component and mantle viscosity variations. A possible way to overcome theoretical deficiencies of Runcorn’s theory as well as some practical limitations of applying Hager and O’Connell’s theory (in the absence of seismic data) is to combine these two methods. In this study, we apply a least-squares analysis to combine these two methods based on the gravity data inversion constraint on mantle flow equations. In particular, we use vertical gravity gradients from the Gravity field and steady state Ocean Circulation Explorer that are corrected for the gravitational contribution of crustal density heterogeneities prior to applying a localized gravity-gradient inversion. This gravitational contribution is estimated based on combining the Vening Meinesz-Moritz and flexural isostatic theories. Moreover, we treat the non-isostatic effect implicitly by applying a band-limited kernel of the integral equation during the inversion. In numerical studies of modeling, the stress field within the South American continental lithosphere we compare the results obtained after applying Runcorn and Hager and O’Connell’s methods as well as their combination. The results show that, according to Hager and O’Connell’s (mantle flow) solution, the maximum stress intensity is inferred under the northern Andes. Additional large stress anomalies are detected along the central and southern Andes, while stresses under most of old, stable cratonic formations aremuch less pronounced or absent. A prevailing stress-vector orientation realistically resembles a convergent mantle flow and downward currents under continental basins that separate Andean Orogeny from the Amazonian Shield and adjacent cratons. Runcorn’s (gravimetric) solution, on the other hand, reflects a tectonic response of the lithosphere to mantle flow, with the maximum stress intensity detected along the subduction zone between the Nazca and Altiplano plates and along the convergent tectonic margin between the Altiplano and South American plates. The results also reveal a very close agreement between the results obtained from the combined and Hager and O’Connell’s solutions. © The Author(s) 2018. Published by Oxford University Press on behalf of The Royal Astronomical Society.

  • 36.
    Forsström, Claes
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Redundans med Rapid Spanning-Tree vs. Flex Links2018Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    In networks where network connectivity is crucial, redundancy is needed. To prevent loops [10] from happening, a number of different protocols are used.

    In this report, Rapid Spanning-Tree Protocol and Flex Links are compared. The purpose is to investigate how the protocol works, the convergence time between the protocols, and if there is some kind of delay from the switch.

    The measurements show that the switches are waiting for some kind of timer before it con-siders a link down after it is physically unplugged. However, if the interface on the switch is shutdown, there is no delay. The results also show that Rapid Spanning Tree can be faster than Flex Links if the link interruption occurs close to a blocked port, otherwise Flex Links converge faster. However, Flex Links cannot see link interruptions beyond its own links, which limiting its area of use.

  • 37.
    Fransson, Sanna
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Olovligt nyttjande av kommunal mark: Kommunens hantering av olovliga överträdelser2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    All land in Sweden is divided into properties and is part of society's infrastructure. Each property has a unique designation and is bounded by a property boundary marked with boundary points. All properties also have one or more owners. The state, county councils, municipalities and individuals can all be owners of properties. The municipality has a role in society as both property owner and authority. Land use in Sweden is governed by Sweden's municipalities through various planning procedures. The largest land areas that the municipality owns are within urban areas where most of the land is local planned. Both the individual and the general interests should be merged about the surfaces for an appropriate use of the land. The municipality as a property owner handles cases where individuals use municipal land unlawfully for private purposes. Interviews have been completed to take part of the municipalities' experiences of unlawful use of municipal land. Examples of noncompliances that occur on municipal land are hedges, garden furniture, compost, waste or buildings. The biggest consequence is that the public places are privatized. The public has the right to stay on someone else's land according to the right of public access and can temporarily use public space for individual purposes if permission exists. If municipal land is used unlawfully for individual purposes, the municipality can use legal measures to deal with the problem. Depending on the type of non-compliances and where it occur, there are several different laws and regulations to relate to. It can be distinguished from newspaper articles and publications on municipal websites that the problem has been around for a long time but has now begun to be discovered more and more by the municipalities. The participating municipalities confirm that unlawful use of municipal land occurs. The phenomenon is perceived more or less as a problem in the various municipalities. The result has also shown that the problem is handled differently and makes it difficult to fulfill the principle of equal treatment. There are no clear guidelines in several of the municipalities for handling such cases. Part of the problem can be reduced already in the planning work if detailed plans are developed with well-thought out surfaces and clear boundaries for public space. At present, large additional resources are required if a municipality is to deal with the problem seriously.

  • 38.
    Fridström, Anders
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Jämförelse av konvergeringstid för OSPF och EIGRP i små och stora topologier2018Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Minimal downtime of the network is important for most of today's enterprise networks. Preferable it shouldn't be noticeable at all, considering all real-time applications used. It is therefore important for the routing protocol to be able to reconvergence fast. In this study OSPF will be compared to EIGRP's convergence time, in both small and large topologies, when a router on the primary path fails.

    The tests were performed in topologies with 8, 18, 34 and 68 physical Cisco routers and L3 switches each with three different scenarios, OSPF, EIGRP without a pre-calculated backup path and EIGRP with a backup route.

    The result shows that EIGRP outperforms OSPF with several seconds in all topologies.

  • 39.
    Gustafsson, Annika
    et al.
    Advokaterna Gustafsson, Arnbom & Hedberg .
    Carlbring, Marianne
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Exploateringsavtal2018 (ed. Upplaga 1)Book (Other academic)
  • 40.
    Haag, Isabelle
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Halldin, Pernilla
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Äldre fastighetsindelningsbestämmelser i konflikt med stadsutveckling och förtätning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many people consider the best way to get rid of the housing shortages is to densify the city in existing neighborhoods, as there is already some operational service and infrastructure available. An obstacle to this densification may be existing plans with property division provisions which lock the cadastral and require extensive plan work to be removed. Many municipalities chose to actively remove property division provisions just before the amendment of the law that took effect with new Planning and Building Act in 2011, which made the repeal more complicated. The municipality of Gothenburg did not actively remove these and now they have about 5000 old and new plans with property division provisions.

    The purpose of this study has been to get a picture of the factors and motives that make it possible to rethink plans with property division provisions. To achieve this, we needed to analyze legislation with preliminary work and the considerations made in Gothenburg on plan requests for cancellation of such provisions. It has also resulted in a survey of areas in Gothenburg. The study is legal-judged and implemented with interactive induction.

    As there have been frequent changes in legislation in attempting to simplify the planning process for the cancellations of property division provisions, to take less time and demand less resources, the study has determined to what extent simplification of the planning process results in a more efficient process. Resource efficiency for municipalities and shorter process time for individuals are the result of a more effective planning process but may also jeopardize legal certainty as neighbors' right to conduct their action is restricted. These aspects have been studied in parallel with the Case Study in Gothenburg and result in more legislative simplifications should be introduced with great caution in order not to jeopardize legal certainty.

    The outcome of the Case Study in Gothenburg, where plan requests were studied, will include a survey of priority areas. They are considered to be a priority as a result of the cancellation of the property division provisions would lead to several new residential lots. These areas consist of properties divided into three categories, where category one is areas that should primarily be a priority for removing the property division provisions in and then categories with areas that constitute second and third priority. The lots are subject to property division provisions, are placed within priority development area and are not affected by cultural programs. These criteria proved to be decisive for the outcome of the plan requests. In addition to this, the residential lots have high values and are of such size that there is possible to make it into two lots.

  • 41.
    Hadenius, Amanda
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Planering av grönytor och bostäder i turiststarka kommuner2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today we are planning and developing a lot in cities and villages. Due to Sweden's increasing population our needs for housings is increasing and the counties planning befall thereafter. But we do have a need of green areas as well, both seen to health in several perspectives but also for our well-wellbeing. Both green areas and housings are common interest that needs to accommodate in every planning, but how do you plan for those? The purpose for this thesis is to analyse and compare two counties with a lot of tourists in their planning of green areas and housings. The comparing counties are west coastal Tanum and the mountain filled Malung-Sälen. To answer the questions in the thesis the counties overview plans, detailed plans and public prints that was relevant to the subject was studied. Also interviews in a semi structured qualitative method was held with the plan managers in both counties. These was held to gather knowledge and understanding. In the thesis the environmental quality goals is also up-to-date specially the goal good built environment since it has similar grounds as the thesis has focused on.

    The conclusion is that the counties that has been reviewed have different issues in planning. They both have different prerequisites which could contribute to the varied results. Since both counties already have bigger green areas outside the planning side, they do not believe that the question regarding green spaces disappearing in the conurbation is a problem. The fact that housings is utilized as secondary residences instead of permanent is nearby nonexistent in Malung-Sälen while it is a challenge in Tanum. The environmental quality goal is not intentional processed on local level which is necessary in order to slow the loss of biodiversity that we have today, however they have both methods that works in environmental advantage but is not mentioned as environmental quality goal in specific. If the differences in the counties planning are due to their different prerequisites and their structure or if the counties in general have different planning methods cannot with absolute certainty be determined from without only two counties. But it can be determined that these do differ.

  • 42.
    Hansson Carlberg, Johan
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Hilmersson, Mikael
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    En utforskande studie om prestanda i utvinning av kryptovalutan Burstcoin2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Talks about cryptocurrencies in society today keeps increasing and currently the most wellknown is Bitcoin. One thing that has been criticized is the amount of energy which Bitcoin consumes and that is one of the reasons why new more environmentally friendly alternatives have been developed. One of these is Burstcoin which uses Proof of Capacity instead of Proof of Work, which is used in Bitcoin. Proof of Capacity is a relatively new concept which uses disk storage instead of computing power. The purpose of this thesis is to explore how mining-performance when mining Burstcoin can be affected by hardware and by using plot files in different ways. This is analyzed by measuring read times and total block times in five different tests. The tests used in this thesis are examining how the size of plot files affect read times and total block times, how different type of storage disks performs when mining Burstcoin, how different instruction sets affect performance, how optimized and non-optimized plot files differs and how continuous plot files performs compared to split up plot files. Beyond this a benchmark is performed on the storage drives to get a baseline for how the drives perform when doing sequential and random reads. The results show that SSD drives perform best while mining, but the difference compared to hard disk drives is too small to motivate the price difference to hard disk drives which are cheaper. The most important thing about instruction sets is to not use SSE2 since it performs a lot worse than SSE4, AVX and AVX2, although the difference between the last three is too small to concretely say that the latest (AVX2) is a requirement when mining. Non-optimized and split up plot files perform worse than their counterparts. Though split up plot files can still be used as long as they are not split up in to too many files since every file increases the number of searches performed by the mining software.

  • 43.
    Hansson, Linda
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Singmo, Anna
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Krav i markanvisningstävlingar2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Land allocations can only be performed by the Swedish municipalities on the land they themselves own. When the municipalities design a land allocation, they have different types of procedures to choose from. One of these is called land allocation competition, when chosen its often for an area which the municipality already have formed a vision regarding what it should become. A competition program is created with certain demands set by the municipality, following the developers create a design for the area and present this. Subsequently the municipality consider the designs and choses the one which falls best in line with the competition program.

    The aim of the study is to investigate how the Swedish municipalities frame the land allocation competitions, and which types of demands they outline in the competition programs.

    All 290 Swedish municipalities were contacted and 200 of them responded on whether they use land allocation competitions, in total 43 municipalities use such.

    The study only contains land allocation competitions that have been completed after January 1st, 2015. A total of 57 land allocation competitions have been examined.The result of the study shows that the Swedish municipalities requires different types of demands, some more specified than others. It can also be shown that demands are outlined which extends beyond such defined in the Swedish constitutional law and the planning and building act.

    In conclusion, municipalities strive to reach goals of sustainable development in the process of building a city. Municipalities demands that exploitation contribute to a sustainable urban planning and design.

  • 44.
    Hjärtinge, Johan
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Nordebo, Daniel
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Anläggningsarrenden för idrottsändamål2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The right to use real estate is an important part of the Swedish history. Leasehold is such a form of right of use and has existed in Swedish law since the introduction of the 1907 nyttjanderättslag (NJL). Since 1970, NJL is a part of the jordabalk (JB). One of the four leaseforms is commercial ground lease, which is a legal institution that has existed since the 1968 reform of NJL. In order to be able to grant land through commercial ground lease, a number of terms are required. The terms "acquisition activity", "building" and "building's importance for the operation of the business" are all unclear formulated in the preparatory works for the NJL. In the preparatory works, sports facilities are excluded from the commercial groundlease and are instead referred to apartment lease. Apartment lease is a form of lease that does not have indirect possession protection and thus the right to replacement compensation when the lease ceases. Reasons for why sports facilities are excluded do not appear from the prepartory work. The legal situation within the commercial ground lease for sports purposes is therefore uncertain. The purpose of the thesis is to investigate to what extent it is possible to grant land for sports purposes through commercial ground lease. This thesis describes, through a legal doctrinal examination, the terms that must be fulfilled in order for a commercial ground lease to exist. How land has been granted for sports purposes is investigated through a sociological investigation of 228 agreements. The result of the thesis shows that land can be granted for sports purposes through commercial groundlease if the operator has an objective profit objective with his business. The fact that it is the tenant who conducts the business on the lease is not decisive. The result also shows that land for sports purposes in the investigated agreements is only granted in exceptional cases through commercial ground lease. Of the 228 agreements, six were granted through commercial ground lease, which corresponds to 3 %. The number of leases through apartment lease was the dominant form with 207 or 91 %. In 81 % of cases, the indirect protection of possession has been agreed away. The conclusion of the thesis is that land can be granted for sports purposes through commercial ground lease to all operations except the non-profit, but that in practice it is no tused. Instead, the agreements are classified as apartment lease. In the thesis's discussion, a resumption is conducted about what is really the main issue for a sport club in need of land.The title of the agreement should not be the most interesting, but whether the tenant is given the right to replacement compensation or not when the lease ceases.

  • 45.
    Irwe, Lina
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Forsell, Denise
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    "Annars går allt åt helvete": en studie om social hållbarhet som kommunal planeringsaspekt i fysisk planering2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis is about social sustainability, more specifically it is about how four different municipal areas handles issues about social sustainability in their spatial planning. The aim of this thesis is to investigate the priority of this topic and which methods that are used to deal with this subject. The purpose is also to investigate the possible connection between social sustainability and mixed use-city. The analysis has been made by studying comprehensive plans, detailed development plans and other documents connected to the plans. The content of these document has then been analyzed in relation to theories about social sustainability and mixed use-city. Municipal officials have been interviewed to get at more nuanced view on how social sustainability is incorporated into the process of planning.

    The result shows that the four comprehensive plans in a similar way talk about the aims of planning for social sustainability. In the detailed development plans the difference however is significant, varying to what extent and in what way social sustainability is described the planning specification. Bigger plans tend to include the subject in a more extensive way, whilst smaller many plans don't incorporate social sustainability at all. During the interviews many of the officials said that planning for social sustainability is difficult matter and called for more concrete methods, and for the municipality to use the methods available, to affect the spatial planning. The methods used were; land allocation, civil dialogue and social impact assessment. One official mentioned that he/she personally used the Gothenburg-matrix and another had regular meetings with local brokers. All officials talked about mixed use in connection to social sustainability.

    The conclusion that the result of this analysis finally led to is about the social impact assessment as a suitable method for planning for social sustainability, but also about the potential need for a legislation. Perhaps that could be the way to include social sustainability into the process of planning.

  • 46.
    Ishida, Yvonne
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Andersson, Jessica
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Kommer kommunernas plan- och bygglovsarbete att svämma över i framtiden?: Klimatförändringar och bostadsbyggande2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med studien är att kartlägga och utreda det juridiska ramverk som kommunerna ska följa samt undersöka praktisk tillämpning hos tre kommuner. Studien ska även belysa eventuella svårigheter i planarbetet och ge en kunskapsöversikt. I denna studie analyseras främst plan- och bygglagens innebörd och hur den kan användas vid anpassning till klimatförändringarna vid plan- och bygglovsarbete. Som komplement intervjuas plan- och bygglovshandläggare i tre kommuner samt en planhandläggare på länsstyrelse i Västra Götalands län.

    Klimatförändringarna är ett faktum, och som en följd kommer bland annat vattennivåerna att fortsätta stiga i landet. Klimatforskningen består av prognoser som dock är behäftade med ett viss mått av osäkerhet. På grund av klimatförändringarna har det skett tillägg i plan- och bygglagens 2 kapitel för att kommunerna måste ta hänsyn till framtida översvämningsrisk vid fysisk planering. Det är därmed inte endast dagens förhållanden som ska beaktas vid planläggning och lovgivning. Det finns en stor mängd rekommendationer och riktlinjer som kommunerna har att förhålla sig till och som kan underlätta arbetet för att följa de regelverk som gäller. Att anpassa den fysiska planeringen till framtida klimatförändringar bör påbörjas nu, eftersom byggnadernas livscykel sträcker sig långt in i framtiden.

    Kommunerna kan arbeta fram specifika dokument som är anpassade efter deras förutsättningar och karterade risker för att underlätta sitt arbete i frågan. Det finns en mängd skeden i plan- och bygglovsprocesserna och det är viktigt att en samverkan finns mellan dem, för att det ska bli ett helhetsperspektiv. Det är en viktig förutsättning för att uppnå en hållbar bebyggd miljö. Eftersom klimatförändringar inte stannar vid kommungränser är det lämpligt att kommunerna samverkar i frågan. Samtliga aktörer behöver en aktuell och bra kunskapsgrund för att underlätta arbetet med översvämningsrisker.

    Lagtext och riktlinjer är tydliga med hur kommunerna ska arbeta, detta kan vara enkelt att genomföra om det finns oexploaterad mark, men vid anpassning till befintlig bebyggelse och infrastruktur uppstår problem. I och med intervjuerna framkom komplexiteten med att tillämpa lagtext i realiteten. En av de tre kommunerna har ändrat i befintliga detaljplaner för att klimatanpassa. Två av tre har egna översvämnings-program vilket är goda exempel på integrering av klimatarbetet. Det finns ingen rättspraxis idag, men det finns motsvarande situationer där kommunens ansvar vid lämplighetsprövningen ifrågasatts.

  • 47.
    Ivarsson, Olof
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Jämförelse av TCP BBR och TCP Cubic gällande Throughput, Cwnd och RTT2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Recently, Google released a new congestion control, TCP BBR. Instead of responding to packet loss as a sign of congestion, BBR tries to avoid congestion by estimating how much bandwidth is available at the bottleneck in the network as well as round-trip time (RTT) and then based on that information deciding its transmission rate. The goal of BBR is to send as much data as possible without creating queues at the bottleneck buffer, which increases the RTT without increasing the throughput. The purpose of this work is to conduct an independent study of how BBR and Cubic behave in different network environments where delay differs to reflect the difference between LAN and WAN communication for the two TCP algorithms. The measurements showed that it might be important to consider whether Cubic and BBR are mixed in the network. Changing to TCP BBR on a device in a low delay network when the other devices in the network uses Cubic results in that the device with BBR gets almost all available bandwidth when the transmissions meet at a common bottleneck.

  • 48.
    Jalking, Tobias
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Davall, Dan-Håkan
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    BFD parametrar med BGP2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In modern computer networks routing is needed to communicate between devices. In order to send packages outside of the local network, it is necessary to use routing protocols whose main task is to establish routing sessions with other units and then share information on how to get to a certain destination. When routers have established a session with each other, a function is required to ensure that the session remains active. This function informs if something should happen between the units. What is used by routing protocols is a periodic transmission of Hello packets between the units to inform each other that they still have a working communication to their "routing peer", where peer is the opposite entity where a session was established.

    When a router receives a Hello packet, the router resets it's so called hold timer and waits to receive the next Hello pack. Hold time is how long a unit waits before explaining the session with the "peered" units as down. Hello times are usually a factor of about 3-4 times how often Hello packages are sent. Routing protocols send Hello packets periodically at second level and sometimes even at minute level, this is dependent on what type of network and what type of routing protocol is used.

    This can be too slow today and more and more people are choosing to implement a protocol called Bidirectional Forwarding Detection (BFD) to achieve the same result (test so that communication between two units works) but much faster when BFD is usually used at millisecond level. BFD is not only faster at finding errors in communication but is also a flexible protocol that can be used in many different types of solutions. The configuration of BFD is done using parameters.

    This study was made to verify the BFD parameter for that Hold Timer had on the Border Gateway Protocol (BGP) routing protocol's detection times when its peering interface disappears (goes down) and then see if the expected results are consistent with reality. The processor load was observed during the test to see if different Hello timers had any impact. The method used was to read and compare log prints outs from the devices when they discovered that the BGP session was down. The study showed that the correlation in general was poor between the times expected against the times being discovered.

  • 49.
    Jensen, Max
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Djärv, Mattias
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Övergångstider och CPU-utnyttjande i First Hop Redundancy Protokoll2018Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Today’s society is in a position where we become more dependent on technology for every day that passes, in pace with this dependency we demand higher availability from the technology that we use. Redundancy is one way of minimizing outages in the network. Therefore, it has been studied if First Hop Redundancy Protocols (FHRP) can be implemented with low transition period for a router to do a change from being standby to become active in each FHRP and to start forwarding packets, all in under 150 milliseconds. It was decided to see if HSRP, VRRP and GLBP can achieve this limit. Furthermore, it was measured how the CPU is affected by this changeover in FHRP. The results show that HSRP is the fastest protocol and can just about make the limit, and that these protocols have a very small load on the router, but that it uses more resources to be in the active mode than in standby-mode.

  • 50.
    Johannesson, Marcus
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Svensson, Sebastian
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Förutsättningar för småhusbyggande i Dalsland2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: In 2012 Boverket calculated a Tobins q for all municipalities in Sweden. Tobin q describes the theoretical profit when building a single-family house, by dividing market value of an existing house with the total production costs of a similar house.

    The municipalities in Dalsland had a Tobins q value between 0,0-0,79. Boverket wrote in their report that a Tobins q below 0,8 means worse possibilities for building new houses, which was true for all the municipalities in Dalsland. This makes it interesting to investigate how many single-family houses that are built in Dalsland, if the housing market has changes to a point that makes it possible to build houses with a theoretical profitability and what would enable more houses to be built.

    Method: To answer how many single-family houses that are built, data, from the planning and construction department was gathered and compiled. Tobins q for the Dalslands municipalities was assessed by dividing the average market value for an existing house with a calculated total production costs for a new house with the same standards. The market values were assessed by looking at sales of single-family houses with the same or similar standard as a new house. The analysis showed that it was too few sales that fit the criteria in all the municipalities, instead all Dalsland was divided in to three submarkets. Rural-, waterfront- and urban locations. The cost of building a new house was calculated for each submarket. The costs that were compiled was for building plot, house, foundation and planning permission.

    What it would take for the housing market to be improved to enable more houses to be built was investigated by conducting interviews with chiefs of municipals, the planning and construction department, real estate agent and a banker.

    Result: How much are being built? 2018 in Dalsland 37 single-family houses was built which results in 0,85 single-family houses per 1000 inhabitants. The study reaches from 2013-2018, but it has shown no clear signs of any changes of the amounts of house that is being built.

    Is it possible to build with theoretical profit? No, it's not likely that you will make a profit from building in Dalsland, but in some locations you can build without taking a loss. Waterfront locations got a Tobins q value of 0,99, which are higher than what the national average was in Sweden 2012 which was 0,9. The two other markets got a somewhat worse result. Rural location got a Tobins q value of 0,75 while urban location got a Tobins q value of 0,68. This study shows that you can't build single-family houses on those locations and make a theoretical profit.

    What would it take for the housing market to be improved to enable more house to be built? The two biggest obstacles according to the municipalities are that the County Administrative Board are turning down requests for dispensation from the Beach Protection Act and that it is hard for people to get a loan to build houses because of the low Tobins q value.

    Their proposal for solutions are that the state needs to make changes, especially legislative changes or additions. For LIS to work better from their point of view, the County Administrative Board should apply a more generous interpretation of the Beach Protection Act, which would result in more dispensations from the coastal protection. They had more solutions for raising their Tobins q value. Examples of these are: grants for new construction of small houses in the countryside, higher grants for apartment buildings and lower the VAT on building materials to name a few.

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