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  • 51.
    Christensen, Johan
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lund, Hannes
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Undersökning av objektorienterad JavaScript i praktiken2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Javascript is a well-used programming language that is mostly used in web development. The development in javascript is not that obvious though; this is because javascript differs from similar programming languages in many aspects. The purpose of this thesis is to ana-lyze javascript projects and find out if any kind of object-oriented javascript is applied, and also check for different design patterns used. The report's findings show that there are few projects that use most of the techniques of object-oriented javascript, and that only a few design patterns are used.

  • 52.
    Dalhammer, Ida
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Kartläggning av allmänna gång- och cykelvägar på kvartersmark: utan rättsligt genomförande2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Detailed development plans regulate how Sweden's land and water should be used. Statutes on detail planning are to be found in the Swedish planning and building act. A detailed development plan must specify public area, private property area and water area. Everybody may enter the public areas which the municipality owns. The private property area is private and has owners like a housing company or an individual. Optional rules can be used in the detailed development plan. This study deals with the optional regulation "x", which is a land reserve for public pathways. "X" is located on the private property areas.The private property owner may suffer from a restriction of their property rights by getting an "x" over the property. To avoid the risk that the public is prevented from passing through the x-field, a right is formed. If no right is formed, the owner of the property can choose to shut the public out. The right in question occurs appropriate by official easement which occurs by an application. An application can be made to the land survey to create an official easement. The land survey investigates if the official easement has an essential use for the property that has the advantage of the easement.Implementation rules are missing for x-areas, which results in that no right is formed. When no rights are formed there is no legal right for the public to use pedestrian and bicycle pathways. The property owner can choose to put up prohibiting signs and barriers to exclude the public, which results in that the x-areas are not filling their purpose. Previous studies have shown that the x-areas are used more often than intended. Its also used as a combination with "g", to avoid costs for the municipality. A "g" in a detail development plan means that a joint facility will be formed, that consist of the property owners in the area. The cost transfer to the members instead. During lectures at University West it has aroused uncertainties who it is that applies for official easement. The purpose of this study is to investigate how often x-areas have been applied for in the three municipalities of Motala, Linköping and Mjölby in Östergötland County, January 1, 2002 – December 31, 2011. The purpose is also to see how many official easements that have been formed for the x-areas.The result of this research shows that the use of x-areas decreases. The last two years very few x-areas have been established. Motala municipality has unlike Linköping and Mjölby an increasing trend of x-areas. However, in 2011 Motala municipality had no establishment of x-areas. The abnormal result indicates a change, even in Motala. Interviews with plan architects in the different municipalities confirm the result above. The plan architects admit to establish fewer x-areas today than a few years ago. Of all x-areas in the study, 44 percent have no official easement. It may have another easement but it is also possible that they have no easement at all.

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  • 53.
    Damfelt, Christoffer
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Nilsson, Simon
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Prestandautvärdering av enkortsdatorn BPI-R1 jämfört med traditionella hemroutrar2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    In modern times IT gets a major role in people lives. More devices get connected and most familymembers have several connected devices which results in a rising utilization of the home network. Due to this we conducted this project with the intent of evaluating the single-board computer BPI-R1 to traditional home routers in order to establish whether it is applicable for common use as a home router.

    The devices was evaluated by measuring the throughput with iperf in several different scenarios. Throughput is the maximum achievable bandwidth after the traffic has been affected by various factors such as overhead.

    The devices that the BPI-R1 was compared to was a TP-link TL-WR1043WND and a Netgear WNR3500L. Iperf3 was used both to generate the traffic and to gather the results of the measurements. The tests was conducted in three steps. Basic tests on a port-to-port basis and two scenario tests. The basic tests was LAN-LAN, LAN-WAN and WIFI-LAN while scenario one was all the basic tests conducted simultaneously. Scenario two was a WAN-max test where four separate data streams were sent from different LAN-ports to the WAN-port. Iperf3 were being run on Dell Latitude E4130 for cabled traffic and a Samsung Galaxy S7 edge were used for the Wireless traffic.

    The results for the basic tests show that LAN-LAN gave similar results on all devices, on LAN-WAN the results differed vastly between the devices. On WIFI-LAN it differed but not as vastly as in LAN-WAN, and the traffic showed typical behavior of wireless transfers. Both in scenario test one and two it displayed major differences in performance between the devices as well as a major difference between scenario tests and basic tests.

  • 54.
    de Blanche, Andreas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Institutionen för data- och informationsteknik, Datorteknik (Chalmers.
    A Slowdown Prediction Method to Improve Memory Aware Scheduling2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Scientific and technological advances in the area of integrated circuits have allowed the performance of microprocessors to grow exponentially since the late 1960's. However, the imbalance between processor and memory bus capacity has increased in recent years. The increasing on-chip-parallelism of multi-core processors has turned the memory subsystem into a key factor for achieving high performance. When two or more processes share the memory subsystem their execution times typically increase, even at relatively low levels of memory traffic. Current research shows that a throughput increase of up to 40% is possible if the job-scheduler can minimizes the slowdown caused by memory contention in industrial multi-core systems such as high performance clusters, datacenters or clouds. In order to optimize the throughput the job-scheduler has to know how much slower the process will execute when co-scheduled on the same server as other processes. Consequently, unless the slowdown is known, or can be fairly well estimated, the scheduling becomes pure guesswork and the performance suffers. The central question addressed in this thesis is how the slowdown caused by memory traffic interference between processes executing on the same server can be predicted and to what extent. This thesis presents and evaluates a new slowdown prediction method which estimates how much longer a program will execute when co-scheduled on the same multi-core server as another program. The method measures how external memory traffic affects a program by generating different levels of synthetic memory traffic while observing the change in execution time. Based on the observations it makes a first order prediction of how much slowdown the program will experience when exposed to external memory traffic. Experimental results show that the method's predictions correlate well with the real measured slowdowns. Furthermore, it is shown that scheduling based on the new slowdown prediction method yields a higher throughput than three other techniques suggested for avoiding co-scheduling slowdowns caused by memory contention. Finally, a novel scheme is suggested to avoid some of the worst co-schedules, thus increasing the system throughput.

  • 55.
    de Blanche, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Disallowing Same-program Co-schedules to Improve Efficiency in Quad-core Servers2017In: Proceedings of the Joined Workshops COSH 2017 and VisorHPC 2017 / [ed] Clauss, Carsten; Lankes, Stefan; Trinitis, Carsten; Weidendorfer, Josef, 2017, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Programs running on different cores in a multicore server are often forced to share resources like off-chip memory,caches, I/O devices, etc. This resource sharing often leads to degraded performance, a slowdown, for the program sthat share the resources. A job scheduler can improve performance by co-scheduling programs that use different resources on the same server. The most common approachto solve this co-scheduling problem has been to make job schedulers resource aware, finding ways to characterize and quantify a program’s resource usage. We have earlier suggested a simple, program and resource agnostic, scheme as a stepping stone to solving this problem: Avoid Terrible Twins, i.e., avoid co-schedules that contain several instances from the same program. This scheme showed promising results when applied to dual-core servers. In this paper, we extend the analysis and evaluation to also cover quad-core servers. We present a probabilistic model and empirical data that show that execution slowdowns get worse as the number of instances of the same program increases. Our scheduling simulations show that if all co-schedules containing multiple instances of the same program are removed, the average slowdown is decreased from 54% to 46% and that the worst case slowdown is decreased from 173% to 108%.

  • 56.
    de Blanche, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Initial Formulation of Why Disallowing Same Program Co-schedules Improves Performance2017In: Co-Scheduling of HPC Applications / [ed] Carsten Trinitis, Josef Weidendorfer, Netherlands: IOS Press, 2017, 1, p. 95-113Chapter in book (Refereed)
    Abstract [en]

    Co-scheduling processes on different cores in the same server might leadto excessive slowdowns if they use the same shared resource, like a memory bus. Ifpossible, processes with a high shared resource use should be allocated to differentserver nodes to avoid contention, thus avoiding slowdown. This article proposesthe more general principle that twins, i.e. several instances of the same program,should be allocated to different server nodes. The rational for this is that instancesof the same program use the same resources and they are more likely to be eitherlow or high resource users. High resource users should obviously not be combined,but a bit non-intuitively, it is also shown that low resource users should also notbe combined in order to not miss out on better scheduling opportunities. This isverified using both a probabilistic argument as well as experimentally using tenprograms from the NAS parallel benchmark suite running on two different systems.By using the simple rule of forbidding these terrible twins, the average slowdownis shown to decrease from 6.6% down to 5.9% for System A and from 9.5% to8.3% for System B. Furthermore, the worst case slowdown is lowered from 12.7%to 9.0% and 19.5% to 13% for systems A and B, respectively. Thus, indicating aconsiderable improvement despite the rule being program agnostic and having noinformation about any program’s resource usage or slowdown behavior.

  • 57.
    de Blanche, Andreas
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lundqvist, Thomas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Terrible Twins: A Simple Scheme to Avoid Bad Co-Schedule2016In: Proceedings of the 1st COSH Workshop on Co-Scheduling of HPC Applications / [ed] Trinitis, Carsten ; Weidendorfer, Josef, Munchen, 2016, Vol. 1, p. 1-6Conference paper (Refereed)
    Abstract [en]

    Co-scheduling processes on different cores in the same server might lead to excessive slowdowns if they use a shared resource,like the memory bus. If possible, processes with a high shared resource use should be allocated to different server nodes to avoid contention, thus avoiding slowdown.This paper introduces the simple scheme of avoiding to coschedule twins, i.e., several instances of the same program.The rational for this is that instances of the same program use the same resources and they are more likely to be either low or high resource users − high resource users should obviously not be combined, but a bit non-intuitively, it is also shown that low resource users should also not be combined in order to not miss out on better scheduling opportunities.This is verified using both a statistical argument as well as experimentally using ten programs from the NAS parallel benchmark suite. By using the simple rule of forbidding twins, the average slowdown is shown to decrease from 6.6% down to 5.9%, and the worst case slowdown is lowered from 12.7% to 9.0%, indicating a considerable improvement despite having no information about any programs' resource usage or slowdown behavior.

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  • 58.
    Deng, Donglu
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Selektivplan upprättad i samband med utbyte av generatorer på Arctic Paper2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här rapporten innehåller en selektivplan som upprättats i samband med utbyte av tre generatorer på Arctic Paper i Munkedal, samt flera selektivplansuppdateringar i övriga skydd. Arbetet har som syfte att bygga upp fördjupande kunskap i säkringsfri teknik i industriella elanläggningar, vilket genomförs som ett examenarbete för högskoleutbildning som elkraftsingenjör.

    På pappersbruket finns idag tre gamla vattenkraftsgeneratorer. Två av de tre nuvarande generatorerna är små och mycket gamla, generatorer som ska bytas ut mot två nya 3MVA synkrongeneratorer. En av de gamla generatorerna ska användas även i framtiden som reserv. Målet med ombyggnadsprojektet är att öka effekten med upp till tre gånger samt att fördubbla energi produktionen. Ställverk till generatorerna har specificerats tidigare i ombyggnadsprojektet.

    Selektivplanen inkluderar inställningar av reläskydd och effektbrytare för generatorerna. Dessutom kommer befintliga överströmsskydd i anläggningen beaktas. Rapporten baseras på selektivitetsteori och beräkningar av kortslutningsströmmar. Rapporten innefattar även uppdatering av vissa selektivplaner i den befintliga elanläggningen i pappersbruket, detta genom att diskutera problemet och justera inställningar av de befintliga reläskydden

    Tekniska beräkningar och reläinställningsplaner ska fungera som verifikation och dokumentation.

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  • 59.
    Edström, Joakim
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Rise of the self-encrypting drive: the possible co-existence of drive encryption, performance and integration2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a study which concerns solid state drives and encryption. Three goals were formulated with the main one being to determine what kind of effect encryption has on a drive's performance. The secondary goal was to determine the current state of storage encryption in relation to awareness and attitudes amongst consumers and companies and also in relation to how easily solutions can be integrated into already working systems. The third minor goal was to determine the performance difference between different encryption software. These three goals were achieved through a background study of current articles, white papers, news and statistics in addition to performing a benchmark study where the performance of eight different encryption solutions representing the most common methods – software encryption, hardware-accelerated encryption through processor instructions and self-encrypting drives – were tested on a fair platform. The results from both the background study and the benchmark measurements show that the self-encrypting drive excel in every area compared to its peers, be it security, performance or system integration. Contradictory to these results is however the fact that general awareness amongst consumers and companies concerning the benefits of self-encrypting drives seems to be quite low and self-encrypting drives on the market are heavily underrepresented.

  • 60.
    Edström, Johan
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Redovisning av lantmäterimyndigheternas handläggningstider och hur de påverkar byggbranschen2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    That the need for housing is very large and will continue to be so for many years in Sweden is well known. To handle the emergency situation, the construction process needs to speed up.  On January 19, 2017, an article was published on the Swedish government's website describing that the survey processing times have to be reviewed. The long processing times are slowing down the construction process and thus adversely affect the construction process in a negative way. The National Land Survey is an authority that works to measure, regulate and distribute cadastral boundaries. This means that The National land survey has a major role in the plan process and because of that a significant impact on the time of the plan process. Especially during the work on detail plans. This bachelor thesis has been carried out at the University West, Sweden, with the purpose of investigating how Sweden’s survey agencies administrative processes affect the construction process.

     Of Swedens 39 municipal survey agencies, 29 have contributed with processing statistics. The study's results have shown that the processing times of municipal surveyors on average are 47.5 weeks in 2016. At the Land Survey, the corresponding equivalent value is 55.1 weeks in 2016. This study clearly indicates that processing times are too long given to what the construction industry is looking for. A majority in the construction industry are saying that a processing time that is longer than 26 weeks is unreasonable in most cases. Although this study has shown that, the construction industry is overall satisfied with the work carried out by the survey agency. In 2016, a new section came into law that will give rights to a broadband connection within a maximum of four months after the application. This means that the survey agencies may be required to give priority to these types of cases, and thus administrative processing times may be affected. The result has shown that there are four different possibilities for getting priority in the line, however, it is too early to state with certainty that the processing times will be affected by the new law.   

  • 61.
    Ek, Albert
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    En kvantitativ studie av minnesbaserade schemaläggningstyper2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's society computer processors are used in everything from smartphones to big server clusters and performance demands are always increasing. To improve performance, additional cores are usually added to the processors but that leads to one problem. The added cores generates additional data traffic to the memory, which put strain on already bandwidth limited memory buss. To mitigate the problem, co-scheduling is used which leads to increased throughput and decreased strain on the memory bus. A co-scheduler contains two parts, an algorithm and a characterization method.The experiments used Slowdown based characterization, Miss rate, Stack distance competi-tion and Solo bandwidth usage, which is four characterization methods and they were co-scheduled togheter with programs from the SPECint suite[1]. The goal was to find out how the methods performed and if the performance was differ on different computer systems.The first step was to create a baseline by executing all programs individually and pairwise. When the baseline was finished all programs could be simulated against every characteriza-tion method. After that the characterization methods could be compared to the baseline executions to see how the characterization methods performed.The characterization methods, who performed better than the average of all the baseline executions are good and have potential. The average value was 8,42% on PC1 and 6,10% on PC2. The average value of the Slowdown based characterization method was 6,24% on PC1 and 3,68% on PC2, which makes it the best characterization method. Solo memory bandwidth usage had 7,25% on PC1 and 4,17% on PC2, which makes it the second best method. Miss rate performed unevenly and got the third place with an average value of 6,37% on PC1 and 6,45% on PC2. Stack distance competition was the worst method with 10,51% on PC1 and 6,17% on PC2.

  • 62.
    Eklund, Oskar
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Engström, Johan
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Preliminärfråga enligt anläggningslagen: En kartläggning av användandet I Västra Götaland, Skåne och Blekinge län 20142016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report examines the use of a special procedure whereby preliminary decision according to the Swedish law called "anläggningslagen" is used. Preliminary decision means that the surveyor can take a decision before the joint facility is valuated or technical work has been done. This is recommended if there is an unclear relationship in the location of the joint facilities or if there is a dispute between a number of interest parties leading to a risk of appeal(s). When a joint facility is introduced it is done so by the law "anläggningslagen". In "anläggningslagen", there are opportunities to create joint facilities for a variety of purposes such as roads, parking lots, water and sewage system and more. To create such a joint facility involves an application by an interested party submitted to The Swedish Mapping, Cadastral and Land Registration Authority (Lantmäteriet) which then handles the case in the manner required by law. The report aims to identify the number of cadastral procedures that make use of preliminary decision, and if there are any clear patterns in situations or purposes. Furthermore the study examines the surveyors own opinions about the preliminary decision. And finally a survey is conducted on the form requirements of the preliminary decision and how it is reported in the cadastral documents in which the proceeding has been used.

    The study is limited both geographically and in time to only examine cadastral documents from Västra Götaland, Skåne and Blekinge County in 2014. During the study, a statistical survey and an interview method have been used. The statistical method was chosen to identify the usage of the preliminary decision in Västra Götaland, Skåne and Blekinge County in an easily distinguishable way. The statistical results show that the usage of a preliminary decision is uncommon, and that it is only used in 2.1 % of the cadastral procedures. The study also shows that the most common purpose of a joint facility is roads. The results from the interviews indicates that the aforementioned section regarding preliminary decision is used in the construction of joint facilities to be a way to simplify handling of the cadastral procedures. In addition, the results show that the surveyors that were interviewed experience that the section is used more commonly in complicated cadastral procedures. After studying over 500 cadastral documents, it is to note that there is not a clear way in how the usage of preliminary decision is presented in the cadastral documents.

    The conclusion of the report is that the usage of the preliminary decision is very rare. A well-utilization of the preliminary decision will lead to a simplified and more time-economical management of complex cases. It is used primarily in complex cadastral procedures when the prospect of the procedure is uncertain and in new construction cases. This specific section is perceived as very useful by the authors after the conclusion of the study.

  • 63.
    Ekstorm, Markus
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Rex, Olle
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Servitut enligt anläggningslagen och fastighetsbildningslagen: En jämförande studie av prövningsförfarandet vid upplåtande av servitut för väg2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through the Joint Facility Act and the Property Formation Act easement for road can be granted. The legislature makes clear that the easement road according to the Joint Facility Act would apply in the case of an independent action for which a property in need of a road for transport to and from the property, and the Property Formation Act would apply when the easement would be granted in connection with a property realloment. There is no explicit restriction to apply the Joint Facility Act in connection with a property reallotment.

    The aim of this study is to investigate how the review procedure is conducted in the individual laws in order to thereby investigate possible similarities and differences. In order to achieve the aim of the study, the legal text, preparatory work and court cases is examined. In order to interpret what the legislature intended and when the laws should be applied. Thereafter the cadastral files where reviewed and interviews with cadastral surveyors were conducted. This in order to compare how the laws are meant to be applied and how they are applied by cadastral surveyors.

    To answer the study questions three different methods has been applied. The applied methods are qualitative -, quantitative- and legal method. The files have been reviewed and the interviews that have been conducted have been limited to Västra Götaland, primarily to facilitate conduction of the interviews in person.

    After completing the analysis of the legal text and its legislative history the study came to the conclusion that the condition "essential importance" in the Joint Facility Act is an optional provision. The study shows that of 47 joint facility files, 31 were are based on an agreement and "essential importance" was motivated in 20 of these 31 acts. This is not really needed according to the conclusion of the legal text. In all the remaining 16 joint facility files "essential meaning" is motivated. Of the 50 property reallotment files that was reviewed "essential meaning" was motivated in 27 files. The interviews showed that all the respondents were of the opinion that "essential importance" is always to be tried regardless of the legislation and is to be viewed as the same condition.

    In summary, the study indicates that there is a difference between how the two acts should be applied and how it is actually applied by the cadastral surveyors. The application of the two laws by the cadastral surveyors is very similar.

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  • 64.
    Ekstrand, Charlotta
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Löfgren, Emelie
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Förslag till sammankoppling av distributionsnät över koncessionsgränsen mellan Trollhättan Energi Elnät AB och Uddevalla Energi Elnät AB2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis has been carried out on behalf of Trollhättan Energi Elnät AB and Uddevalla Energi Elnät AB. This is a preliminary study of a possible interconnection between the two companies 12 kV electric power networks at the joint concession border in the rural area Öresjö. It’s the technical and economic aspects of an interconnection that has been studied.

    The tolerance for interruptions in the electricity supply is decreasing in society which requires high service reliability from the electricity network operators. Due to legal requirements the electricity network operators are obliged to compensate customers which are affected by unplanned interruptions longer than twelve hours. A possible interconnection would provide the operators with an additional stand-by supply in the area and thereby increase the service reliability.

    The interconnection of the two electricity grids is possible between the substations Hedetorpet and T185 Fiskaretorpet who are situated one kilometer from each other. Calculations have been carried out on the basis of two possible approaches with two different load currents, which shows that the two power grids have sufficient capacity to cope with an interconnection. The two electricity network operators will have to compensate for the increased ground fault currents in the electricity grid.

    The planned rout for the new line will follow the road 2027 and will consist of a 150 mm2 aluminum PEX-cable and a new substation containing a 100 kVA:s transformer. In order to avoid the application for line concession a high voltage cable cabinet could be placed on the concession line.

    The budget for an interconnection between the two electricity grids, which has been compiled from EBR's design directory P2, is estimated to 1.5 million SEK including an additional fee of 10 % for unforeseen costs.

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  • 65.
    Elgh, Patrik
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lundmark, Tobias
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Elprojektering av nya lokaler2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out on behalf of Midroc Electro AB in Stenungsund. The assignment was to design the electrical installation for an extension of new premises and come up with a cost estimate for this. The extension will include electrical installation in six new offices, a conference room, storage room and an equipment room.

    The project planning is carried out in accordance to Swedish national electrical safety board's regulations and Swedish standards thus meeting the requirement for good electrical safety practice.

    The lighting in the premises is designed according to the guidelines of the Swedish work environment authority, since poor lighting can cause stress, fatigue and glare. Control of lighting will be made using a combination of two intelligent control systems, KNX and DALI.

    In the storage room, corridors and technology room the lights will be controlled by motion sensors. In the conference room the lights can be controlled with push buttons or by remote control. In offices the lights will be controlled by a push button. In offices and the conference room network sockets will be installed. In the corridors there will be power- and network sockets above the ceiling for wireless access points. General sockets for power have been allocated according to Swedish standards.

    The Installation drawings are rendered in the computer program EasyEL and resulted in lighting-, ducting-, power- and telecommunication drawings. Sizing calculations and documentations of the electrical installations were carried out in the computer program FEBDOK.

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  • 66.
    Elmersson, Åsa
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Grafström, Joel
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Småhusbyggande i marknadssvaga Götalandskommuner: En studie i hur mycket det byggs och hur det finansieras2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sverige räknas till blandekonomierna. Blandekonomin har sin utgångspunkt i marknadsekonomin men staten reglerar marknaden till viss del. Detta gäller också för bostadsmarknaden. Så utgångspunkten är således att marknaden ska styra priset på småhus genom tillgång och efterfrågan. Det är ena sidan. Den andra sidan är regleringarna. När det kommer till bostäder är det till exempel bolånetaket och amorteringskravet. Bolånetaket utgår från bedömt marknadsvärde. Är det ett begagnat hus räknas som regel försäljningspriset som marknadsvärde medan det i de fall det är ett helt nytt hus görs en förhandsvärdering inför byggnationen. Maximalt kan 85 procent av marknadsvärdet belånas, med fastigheten som säkerhet, för att finansiera ett husköp eller en nybyggnation. På attraktiva marknader är detta sällan något problem eftersom marknadsvärdet på nybyggnationerna oftast är högre än kostnaderna för att bygga huset. Men hur är det då i områden där det inte är så, utan där produktionskostnaderna istället ofta är högre än det förväntade marknadsvärdet? Rent teoretiskt borde det inte kunna byggas småhus i dessa områden med annat än att de som bygger satsar eget kapital och/eller lägger ner mycket eget arbete. Är det så verkligheten ser ut eller lånar bankerna trots allt ut pengar? Och byggs det några småhus överhuvudtaget i dessa områden? Med breda penseldrag har detta undersökts. Urvalet för studien är de femton kommuner i Götaland med lägst Tobins q-värde, det vill säga hade sämst relation i kvoten marknadspris på en befintlig bostad genom den totala produktionskostnaden för en likartad bostad ur Boverkets lista för år 2012. I studien har bygglovsstatistiken i undersökningskommunerna och jämförelsekommunerna studerats. Rapporten visar att det relativt sett byggs färre småhus i de undersökta kommunerna. I de femton undersökta kommunerna med svaga bostadsmarknader är medianvärdet 0,20 beviljade bygglov per tusen invånare. Motsvarande siffra för de tio mest folkrikaste kommunerna i Götaland är 0,69, nästan 3,5 gånger mer under samma år. Studien har också undersökt den teoretiska lönsamheten på de platser där bygglov utfärdats i de studerade kommunerna. En teoretisk produktionskostnad har antagits och en modell skapats för att kunna massvärdera samtliga bygglov med hjälp av taxeringsvärden. Resultatet med den här modellen ger att i 87 procent av fallen går det inte med säkerhet att säga att nybyggnationen är ekonomiskt lönsam vid färdigställandet. Slutligen har studien även undersökt hur nybyggnationerna finansieras genom att inteckningsbeloppen för varje nybyggt småhus har granskats. Av de nybyggnationer där interimistiskt slutbesked eller slutbesked har erhållits visar det sig att 20 procent av nybyggnationerna inte har några inteckningar alls och således har finansierats på annat sätt än genom lån med huset som säkerhet. Bedöms istället, utifrån datamaterialet, den teoretiska produktionskostnaden i förhållande till ett uppskattat marknadsvärde är knappt 50 procent av dessa nybyggnationer helt bankfinansierade. Således är cirka 30 procent av nybyggnationerna sannolikt delvis bankfinansierade. Även tecken på övervärdering av nya bostäder har uppmärksammats.

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  • 67.
    Engström, Anders
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hallnor, Fillippa
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Registerföring av rennäringens utökade rättigheter: Hantering av sedvanerätter i fastighetsregistret gällande mark med statligt ursprung2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reindeer keepers in Sweden have the right to pursue reindeer husbandry on land that they do not own. That is governed by law. The rights are more extensive regarding land that is now, or formerly was, owned by the Swedish state. The reindeer keepers may for example cut down trees in order to collect wood and fuel needed for their business. Lantmäteriet (the Swedish mapping, cadastral and land registration authority) shall since 30 June 1992 insert a comment in the real property register to inform about the existence of the extensive right of reindeer keeping, actuated when the state sells land to a private owner. The main focus of the study is to investigate how Lantmäteriet has handled the insertion of such information in Arvidsjaur, Gällivare and Vilhelmina municipality between year 1992 and 2017.  By finding and examining transcripts from the real property register on properties which the state has sold land to, the study aims to show how the task has been handled. The sale of land owned by the state has mainly been managed by the company Sveaskog AB. This derives a natural selection consisting of land transfers made from properties owned by that company. The properties that have received land are categorized with respect to whether they have information about the extensive right of the reindeer keepers and to who the owner of the property is. This determines whether the task has been handled correctly or not. The information has been incorrectly left out in 65 % of the insertions in Gällivare and nor in Arvidsjaur or Vilhelmina has the work been done correctly. The result also gives an insight into the working routines of the cadastral surveyors and it shows how they approached the task. They seem to have developed an approach that goes beyond what is written in the guidelines from Lantmäteriet. This is one of the phenomena which is further discussed in the analysis. The study analyzes the underlying factors to why the information is not inserted. A discussion is held about how the formulation of the information could be clarified to make it easier for everybody to understand it. The conclusion tells that the work has been differently managed in the different municipalities. The work routines should be clarified or incorporated into the guidelines from Lantmäteriet and the current legislation should be questioned since we consider that it doesn’t always follow the purpose of the information. Concrete suggestions show how to more comprehensively present the information.

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  • 68.
    Eriksson, Christoffer
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Framtagning av tillförlitlighetsdata för ställverksapparater i Vattenfalls regionnät2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Higher demands are placed on network operators regarding the delivery quality. Part of the decision-making in constructions or renovations is to estimate costs for any possible fault on the network. To make these calculations, it is required that the correct input data is available. The relevant data shows what can be expected of a component, how reliable the devices are. This report focused on what data is available to calculate a result with reliable fault frequency for switchgear devices from different sources. The research only includes the transmission network and focus has been on finding reliable sources where the results has been documented, which presents the opportunity to make an assessment of the reliability. Cigré has previously conducted the most comprehensive report and collected data from around the world. Electrical companies from 28 countries contributed which was analyzed and summarized in multiple reports. Other sources reviewed for this research are ENTSO-E and Nordel, who for several years has compiled statistics from the Nordic countries in annual reports. Something that attracted attention in the work is that Vattenfall has performed an incorrect reporting of transformer fault in recent years. This results in multiple failure rates of Nordel and ENTSO-E is not useful, it should be reviewed by Vattenfall to contribute to this collection statistics that are useful for all grid companies. In this research, recommended error rates are presented based on the collected statistics. The values presented are for power transformers, circuit breakers, disconnectors, earthing switches and instrument transformers. The voltage levels included varies for the different components.

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  • 69.
    Eriksson, Jeanette
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Windle, Sigrid
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Gemensamma inteckningar: konsekvenser som uppkommer av att klyva en intecknad fastighet2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Co-owned properties can be partitioned to suspend the joint ownership. When a mortgaged property is being partitioned, the parted plots will be jointly mortgaged. Land code (JB 22:2) states a congruence claim, which prohibits the possibility to obtain new mortgages as long as there is a common mortgage liability. This can only be lifted if all property owners cooperate to apply for mortgage measure. There are situations where a property owner refuses to contribute to a mortgage action and as a result all property owners are prevented the possibility of obtaining new mortgages.

    The purpose of the study is to investigate whether land surveyors inform property owners about the consequences that arise from partitioning a mortgaged property and if there is any way to avoid or resolve the situation.To answer the question chosen cadastral documents have been examined and interviews conducted with land surveyors, a course tutor in the mortgage field and a lawyer at the enrolment authority.The results have been compiled with the legislative text, preparatory work and literature on the subject.

    The finding of the report shows that land surveyors mention the mortgages in many cases. But the information does not protect property owners from the consequences that may arise from the partition of a mortgaged property.

    The conclusion is that the problem is not caused by any entity doing wrong. Upon partitioning of a mortgaged property neither land surveyors, enrolment authority or another can prevent the arising of the situation. Land Surveyors are obligated to inform property owners and thus increasing their awareness of the value of managing mortgages. It requires that the land surveyors be given clear instructions on their obligations to provide information. A solution to the issue would require legislative changes for the problem to be solved. This problem may be rare but causes a really difficult situations for the property owner. The law should provide land surveyors the ability to manage mortgage.

  • 70.
    Eriksson, Joacim
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hedlund, Robin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Cisco ACI and VMware NSX, a comparison between Software Defined Networks2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's network applications and cloud services has made data centres more utilised and important than ever. This has put big responsibility on the network in data centres to forward traffic reliably, to ensure business continuity. Several techniques to make that process more effective has in recent years emerged, among one of them is Software Defined Networking or SDN as it is usually referred to. The general concept behind SDN is that the network intelligence, such as routing and packet filtering, is moved out of the individual boxes and put into a centralised controller which would be programmed by an administrator which in turn would instruct the now unintelligent boxes how traffic should be forwarded, in contrast to instruct the boxes one by one. There are many SDN protocols available today, both open and commercial. One popular open alternative is OpenFlow capable switches with the OpenDaylight controller. In this paper we investigated and compared two major commercial options: Cisco ACI and VMware NSX. We gave a brief introduction to some common problems in today´s data centres and kept those in mind when doing the comparison of Cisco ACI and VMware NSX. We concluded that ACI and NSX does not try to solve all problems in today's data centres, rather, each focuses on their own set of problems, and sometimes both can be used to complement each other.

  • 71.
    Eriksson, Joacim
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Wikman, Fredrik
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Comparative study of 802.11n and 802.3 in Quality of Service enabled networks2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Datornätverk har historiskt sett alltid blivit konstruerade att arbeta på en "så-gått-det-kan" basis [5]. Detta har funkat bra i många år när endast datatrafik använde nätverket, men, i moderna konvergerade nätverk där datatrafik delar utrymme med telefontrafik (VoIP) och videotrafik som både har sina egna krav på nätverket för att erbjuda en acceptabel tjänst. För att underlätta så har flera Quality of Service (QoS) tekniker utvecklas som kan ge viss trafik högre prioritet över annan trafik och ser även till att trafiken får den bandbredd som den kräver. Dagens användare kräver även högre mobilitet vilket 802.11 [1, 6] som använder radiovågor för att förse användare med nätverksåtkomst istället för att vara förankrad till en kabel som är fallet för det traditionella sättet att erbjuda nätverksåtkomst med 802.3 [3]. Den här studien presenterar en jämförelse mellan 802.11 och 802.3 med och utan QoS konfigurerat. Under varje experiment genererades trafik som simulerade ett belastat nät. Den här trafiken ökade gradvists tills nätverket var belastat till 200%. Under testerna mättes fördröjning, jitter, paketförluster och genomströmningshastighet. Resultatet jämfördes mot kraven som G.711 har, som är en typ av VoIP codec, för att se om det är möjligt att ersätta en trådad uppkoppling med en trådlös. Resultatet visade att med QoS påsatt, presterade trådlöst långt under de maximala värderna för jitter, fördröjning, paketförlust och försedde med tillräcklig genomströmningshastighet för en acceptabel prestanda under ett högt belastat nätverk.

  • 72.
    Eriksson, Johan
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Laserskanning i antikollisionsanalyser för konstruktioner2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out in collaboration with Maersk Oil. Their mission for me was to develop a standard to check that their CAD models match the data that has been generated by laser scanned point clouds. The models are used in simulations of structures that are to be joined, and avoiding a collision when the structures physically are joined together.

    After an item has been scanned with a laser scanner raw data will be acquired in the form of a point cloud. Once the point cloud afterwards is exported to a construction program which can perform these simulations, the client are not entirely sure if the raw data coming into the construction program without any defects.

    The work has progressed through various stages, including the study of the market, field work with data collection, coordination of interviews and contacts with various suppliers and specialists in the field.

    The report contains a basic knowledge of software and laser scanning and a recommendation to use the software Geomagic Qualify to verify that the models are consistent with the actual structures.

  • 73.
    Eriksson, Kevin
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Seidl, Kristoffer
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Reservkraft i Vattenfalls norrlandsnät2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Today, the power grid in the Swedish province of Norrland is particularly sensitive to interruptions. With a high proportion of overhead and radial lines and increasing demand on reliability of the power supply means backup power supply is often necessary to meet the requirements.

    By studying interruption reports available at Vattenfall the necessary data about faults that exceed statutory periods was gathered. Observations in Vattenfalls network information system formed the basis for the assessment of the grid structure in the area.

    Information about the data on the relevant plant sections was retrieved via the manufacturers' datasheets.

    Today access to the back-up power is unevenly distributed where sensitive areas in general have considerably less access to back-up power than less sensitive areas. In addition, the available back-up power is not used to the extent it would be possible because it can be seen as a waste of resources. Relocation of some back-up power to areas with high fault rates is suggested in order to reduce the compensation that must be paid to the customers in case of long power outages.

    It was also examined during the project if proper fault disconnection within a reasonable time frame is met. This resulted in a table that can be used to verify if the connected power supply has the required short-circuit power to ensure fault disconnection.

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  • 74.
    Eriksson, Tommie
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Landgren, Alexandra Ryrå
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Failover to Wired vs. Wireless - Which one is better with VoIP?2017Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This project is about how failover through wired and wireless links affects VoIP. The information of this thesis is relevant since VoIP is widely used and redundancy is a requirement in all types of enterprise networks. The goal of this study is to see whether a wireless link is equally good to a wired link when it comes to failover. Will the VoIP call experience more packet loss over a wireless link or is it possible to use one as a backup link for the wired network?

    To find out, the difference between the two link types are measured by how many packets that are lost during a call - both in a scenario without failover and a scenario with failover. This is done by setting up two different topologies, one with a wired link and one with a wireless link to the backup device, with two IP-phones, one in each end of the network. The phones initiate a call and while this call is up, Wireshark is used to capture the packets for analysis. Measurements are be done both with and without a failover occurrence in both the wired and the wireless topology.

    The results of this study show that the scenario with a wireless link have a higher average packet loss than the wired one. However, the difference is small enough to overlook since the wireless link doesn’t affect the call more than the wired link does. It can also be seen in the results that the average packet loss during a failover is lower if the call is initiated by an IP-phone that have a router between itself and the failover devices compared to when the call is initiated by an IP-phone with a switch between itself and the failover devices.

  • 75.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    A theoretical discussion on Vening Meinesz-Moritz inverse problem of isostasy2016In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 207, no 3, p. 1420-1431Article in journal (Refereed)
    Abstract [en]

    The Moho surface can be determined according to isostatic theories and the recent Vening Meinesz-Moritz (VMM) theory of isostasy has been successful for this purpose. In this paper, we will study this method from a theoretical prospective and try to find its connection to the Airy-Heiskanen (AH) and Vening Meinesz original theories. We develop Jeffrey’s inverse solution to isostasy according to the recent developments of the VMM method and compare both methods in similar situations. We will show that they are generalisations of the AH model in a global and continuous domain. In the VMM spherical harmonic solution for Moho depth, the mean Moho depth contributes only to the zero-degree term of the series, whilst in Jeffrey’s solution it contributes to all frequencies. We improve the VMM spherical harmonic series further so that the mean Moho can contribute to all frequencies of the solution. This modification makes the VMM global solution superior to the Jeffrey one, but in a global scale, the difference between both solutions is less than 3 km. Both solutions are asymptotically-convergent and we present two methods to obtain smooth solutions for Moho from them. 

  • 76.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Local recovery of lithospheric stress tensor from GOCE gravitational tensor2017In: Geophysical Journal International, ISSN 0956-540X, E-ISSN 1365-246X, Vol. 209, no 1, p. 317-333Article in journal (Refereed)
    Abstract [en]

    The sub-lithospheric stress due to mantle convection can be computed from gravity data and propagated through the lithosphere by solving the boundary-value problem of elasticity for the Earth's lithosphere. In this case, a full tensor of stress can be computed at any point inside this elastic layer. Here, we present mathematical foundations for recovering such a tensor from gravitational tensor measured at satellite altitudes. The mathematical relations will be much simpler in this way than the case of using gravity data as no derivative of spherical harmonics or Legendre polynomials is involved in the expressions. Here, new relations between the spherical harmonic coefficients of the stress and gravitational tensor elements are presented. Thereafter integral equations are established from them to recover the elements of stress tensor from those of the gravitational tensor. The integrals have no closed-form kernels, but they are easy to invert and their spatial truncation errors are reducible. The integral equations are used to invert the real data of the gravity field and steady-state ocean circulation explorer (GOCE) mission, in November 2009, over the South American plate and its surroundings to recover the stress tensor at a depth of 35 km. The recovered stress fields are in good agreement with the tectonic and geological features of the area.

  • 77.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Non-singular expressions for vector and gradient tensor of gravitation in a geocentric spherical frame2008In: Computers & Geosciences, ISSN 0098-3004, E-ISSN 1873-7803, Vol. 34, no 12, p. 1762-1768Article in journal (Refereed)
    Abstract [en]

    The traditional expressions of the gravitational vector (GV) and the gravitational gradient tensor (GGT) have complicated forms depending on the first- and the second-order derivatives of associated Legendre functions (ALF), and also singular terms when approaching the poles. This article presents alternative expressions for the GV and GGT, which are independent of the derivatives, and are also non-singular. By using such expressions, it suffices to compute the ALF to two additional degrees and orders, instead of computing the first and the second derivatives of all the ALF. Therefore, the formulas are suitable for computer programming. Matlab software as well as an output of a numerical computation around the North Pole is also presented based on the derived formulas.

  • 78.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    On Vening Meinesz-Moritz and flexural theories of isostasy and their comparison over Tibet Plateau2016In: Journal of Geodetic Science, ISSN 2081-9919, E-ISSN 2081-9943, Vol. 6, p. 139-151Article in journal (Refereed)
    Abstract [en]

    Gravity and topographic/bathymetric data are used for gravimetric modelling of Moho discontinuity by hydrostatic or flexural theories of the isostasy. Here, two hydrostatic models, based on the Vening Meinesz-Moritz (VMM) principle, and two based on the loading theories and flexural isostasy are compared over Tibet Plateau. It is shown that the Moho models generated based on the VMM theory and flexural isostasy have very good agreements if the mean compensation depth and the mean elastic thickness are selected properly. However, the model computed based on the flexural isostasy is smoother. A more rigorous flexural model, which considers the membrane stress and curvature of the lithosphere, is used to model the Moho surface over the study area. It is shown that the difference between the Moho models, derived by considering and ignoring these parameters, is not significant. By combination of the flexural and VMM hydrostatic models new mathematical formulae for crustal gravity anomalies are provided and it is shown that the crustal gravity anomalies produced by them are also equivalent.

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  • 79.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Alizadeh Khameneh, Mohammad AMin
    KTH.
    Two-epoch doptimal design of displacement monitoring networks2015In: Boletim de Ciências Geodésicas, ISSN 1413-4853, E-ISSN 1982-2170, Vol. 21, no 3, p. 484-497Article in journal (Refereed)
    Abstract [en]

    In the traditional method of optimal design of displacement monitoring networks a higher precision, times better than the desired accuracy of displacements, is considered for the net points in such a way that the accuracy of the detected displacements meets the desired one. However, in this paper, we develop an alternative method by considering the total number of observations in two epochs without such a simple assumption and we call it two-epoch optimisation. This method is developed based on the Gauss-Helmert adjustment model and the variances of the observations are estimated instead of the weights to optimise the observation plan. This method can deliver the same results as the traditional one, but with less required observations in each epoch

  • 80.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Ebadi, Sahar
    University of Tehran, Department of Surveying Engineering, Iran.
    Tenzer, Robert
    University of West Bohemia, New Technologies for the Information Society (NTIS), Czech Republic.
    Isostatic GOCE Moho model for Iran2017In: Journal of Asian Earth Sciences, ISSN 1367-9120, E-ISSN 1878-5786, Vol. 138, p. 12-24Article in journal (Refereed)
    Abstract [en]

    One of the major issues associated with a regional Moho recovery from the gravity or gravity-gradient data is the optimal choice of the mean compensation depth (i.e., the mean Moho depth) for a certain area of study, typically for orogens characterised by large Moho depth variations. In case of selecting a small value of the mean compensation depth, the pattern of deep Moho structure might not be reproduced realistically. Moreover, the definition of the mean compensation depth in existing isostatic models affects only low-degrees of the Moho spectrum. To overcome this problem, in this study we reformulate the Sjöberg and Jeffrey’s methods of solving the Vening-Meinesz isostatic problem so that the mean compensation depth contributes to the whole Moho spectrum. Both solutions are then defined for the vertical gravity gradient, allowing estimating the Moho depth from the GOCE satellite gravity-gradiometry data. Moreover, gravimetric solutions provide realistic results only when a priori information on the crust and upper mantle structure is known (usually from seismic surveys) with a relatively good accuracy. To investigate this aspect, we formulate our gravimetric solutions for a variable Moho density contrast to account for variable density of the uppermost mantle below the Moho interface, while taking into consideration also density variations within the sediments and consolidated crust down to the Moho interface. The developed theoretical models are applied to estimate the Moho depth from GOCE data at the regional study area of the Iranian tectonic block, including also parts of surrounding tectonic features. Our results indicate that the regional Moho depth differences between Sjöberg and Jeffrey’s solutions, reaching up to about 3 km, are caused by a smoothing effect of Sjöberg’s method. The validation of our results further shows a relatively good agreement with regional seismic studies over most of the continental crust, but large discrepancies are detected under the Oman Sea and the Makran subduction zone. We explain these discrepancies by a low quality of seismic data offshore.

  • 81.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hussain, Matloob
    University West, Department of Engineering Science. Earth Sciences department, Quaid-i-Azam University, Islamabad, Pakistan.
    Relationship amongst gravity gradients, deflection of vertical, Moho deflection and the stresses derived by mantle convections: a case study over Indo-Pak and surroundings2015In: Geodynamics research international bulletin, E-ISSN 2345-4997, Vol. 3, no 4, p. I-XIII, article id 12Article in journal (Refereed)
    Abstract [en]

    All  quantities,  which are  measured  in  the  gravity  field  of  the  Earth are affected by  the  field,  therefore,  there should  be correlations  amongst  them.  Here,  we  focus  on  some  gravimetrically-determined  quantities  like  deflections  of  vertical, deflections of Moho, vertical-horizontal gravity gradients and the shear sub-lithospheric stress components due to mantle convection. We show that how these quantities are related to each other mathematically so that one of them can be written in term of another. This somehow proves the presence of the mentioned correlations theoretically. Also, we generate the maps of these quantities over the Indo-Pak and surrounding areas and show how similar they are. Thereafter, they are explained and  interpreted  geologically.  Our  investigations  show  that  the  maps  of  these  quantities  are  in  good  agreements  with topographic and geological features. The map of the vertical-horizontal gravity gradients shows more detailed information of the  gravity field due to  signal amplification at high  degrees,  that of Moho deflection shows sub-surface features due to reduction of the effect of topographic masses. The map of the shear sub-lithospheric stress components is much smoother than the gradients, as expected, and has good agreement with the collisional and subduction zones as well. 

    Relationship amongst gravity gradients, deflection of vertical, Moho deflection and the stresses derived by mantle convections-a case study over Indo-Pak and surroundings. Available from: https://www.researchgate.net/publication/292538682_Relationship_amongst_gravity_gradients_deflection_of_vertical_Moho_deflection_and_the_stresses_derived_by_mantle_convections-a_case_study_over_Indo-Pak_and_surroundings [accessed Feb 1, 2016].

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  • 82.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hussain, Matloob
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Quaid-i-Azam University, Department of Earth Sciences, Islamabad 45320, Pakistan.
    Tenzer, Robert
    Wuhan University, The Key Laboratory of Geospace Environment and Geodesy, Wuhan 430079, China.
    Romeshkani, Mohsen
    University of Tehran, School of Surveying and Geospatial Engineering, College of Engineering, Tehran 14395-515, Iran.
    Moho density contrast in central Eurasia from GOCE gravity gradients2016In: Remote Sensing, ISSN 2072-4292, E-ISSN 2072-4292, Vol. 8, no 5, p. 1-18, article id 418Article in journal (Refereed)
    Abstract [en]

    Seismic data are primarily used in studies of the Earth's inner structure. Since large partsof the world are not yet sufficiently covered by seismic surveys, products from the Earth's satellite observation systems have more often been used for this purpose in recent years. In this study we use the gravity-gradient data derived from the Gravity field and steady-state Ocean Circulation Explorer (GOCE), the elevation data from the Shuttle Radar Topography Mission (SRTM) and other global datasets to determine the Moho density contrast at the study area which comprises most of the Eurasian plate (including parts of surrounding continental and oceanic tectonic plates). A regional Moho recovery is realized by solving the Vening Meinesz-Moritz's (VMM) inverse problem of isostasy and a seismic crustal model is applied to constrain the gravimetric solution. Our results reveal that the Moho density contrast reaches minima along the mid-oceanic rift zones and maxima under the continental crust. This spatial pattern closely agrees with that seen in the CRUST1.0 seismic crustal model as well as in the KTH1.0 gravimetric-seismic Moho model. However, these results differ considerably from some previously published gravimetric studies. In particular, we demonstrate thatt here is no significant spatial correlation between the Moho density contrast and Moho deepening under major orogens of Himalaya and Tibet. In fact, the Moho density contrast under most of the continental crustal structure is typically much more uniform.

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  • 83.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hussain, Mutloob
    Department of Earth Sciences, Quad-i-Azam University, Islamabad 45320, Pakistan.
    An approach to Moho discontinuity recovery from on-orbit GOCE data with application over Indo-Pak region2016In: Tectonophysics, ISSN 0040-1951, E-ISSN 1879-3266, Vol. Part B, p. 253-262Article in journal (Refereed)
    Abstract [en]

    In this research, a modified form of Vening Meinesz-Moritz (VMM) theory of isostasy for the second-order radial derivative of gravitational potential, measured from the Gravity field and steady-state Ocean Circulation Explorer (GOCE), is developed for local Moho depth recovery. An integral equation is organised for inverting the GOCE data to compute a Moho model in combination with topographic/bathymetric heights of SRTM30, sediment and consolidated crystalline basement and the laterally-varying density contrast model of CRUST1.0. A Moho model from EGM2008 to degree and order 180 is also computed based on the same principle for the purpose of comparison. In addition, we compare both of them with the 3 available seismic Moho models; two global and one regional over the Indo-Pak region. Numerical results show that our GOCE-based Moho model is closer to the all seismic models than that of EGM2008. The model is closest to the regional one with a standard deviation of 5.5 km and a root mean squares error of 7.8 km, which is 2.3 km smaller than the corresponding one based on EGM2008.

  • 84.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hussain, Mutloob
    Quaid-i-Azam University, Department of Earth Sciences, 45320 Islamabad, Pakistan.
    Tiampo, Kristy F.
    University of Colorado at Boulder, Department of Geological Sciences and CIRES, USA.
    Towards sub-lithospheric stress determination from seismic Moho, topographic heights and GOCE data2016In: Journal of Asian Earth Sciences, ISSN 1367-9120, E-ISSN 1878-5786, Vol. 129, p. 1-12Article in journal (Refereed)
    Abstract [en]

    Sub-lithospheric stresses can be estimated by analysis of gravity field measurements. Depending on the measured gravimetric quantity, different methods can be employed to estimate those sub-lithospheric stresses. Here, we further develop the Runcorn's theory for estimation of mantle stresses (1967) such that a Moho model and full topographic information are used to recover the function from which the stress can be computed by taking derivatives northwards and eastwards. We develop new integral equations for such a purpose and recover this function by solving those integral equations locally over the Indo-Pak (India-Pakistan) region from (1) a gravimetric Moho model computed from the SRTM (Shuttle Radar Topography Mission) and the Earth gravity model EGM2008, (2) SRTM and the seismic Moho model of CRUST1.0 and (3) data and measurements of the GOCE (Gravity field and steady-state Ocean Circulation Explorer) mission. Finally, we perform a joint inversion of seismic and GOCE data for the same purpose. The numerical results show that the use of a seismic Moho model recovers information about the stress field which is not seen in the results derived from a gravimetric Moho model. A combination of the seismic Moho model, SRTM and GOCE yields a better stress field than that of either the seismic and/or gravimetric data alone. The magnitudes of the sub-lithospheric stress are computed from the shear stress components over the area and good agreement is seen between the recovered combined stress field, the regional tectonic boundaries and the seismicity of the World Stress Map 2008 database.

  • 85.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Royal Institute of Technology, Division of Geodesy, Stockholm, Sweden .
    Lars E:, Sjöberg
    Royal Institute of Technology, Division of Geodesy, Stockholm, Sweden .
    The modified best quadratic unbiased non-negative estimator (MBQUNE) of variance components2008In: Studia Geophysica et Geodaetica, ISSN 0039-3169, E-ISSN 1573-1626, Vol. 52, no 3, p. 305-320Article in journal (Refereed)
    Abstract [en]

    Estimated variance components may come out as negative numbers without physical meaning. One way out of this problem is to use non-negative methods. Different approaches have been presented for the solution. Sjöberg presented a method of Best Quadratic Unbiased Non-Negative Estimator (BQUNE) in the Gauss-Helmert model. This estimator does not exist in the general case. Here we present the Modified BQUNE (MBQUNE) obtained by a simple transformation from the misclosures used in the BQUE to residuals. In the Gauss-Markov adjustment model the BQUNE and MBQUNE are identical, and they differ in condition and Gauss-Helmert models only by a simple transformation. If the observations are composed of independent/disjunctive groups the MBQUNE exists in any adjustment model and it carries all the properties of the BQUNE (when it exists). The presented variance component models are tested numerically in some simple examples. It is shown that the MBQUNE works well for disjunctive groups of observations.

  • 86.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Division of Geodesy, Royal Institute of Technology, Stockholm, Sweden.
    Lars E., Sjöberg
    Division of Geodesy, Royal Institute of Technology, Stockholm, Sweden.
    Ramin, Kiamehr
    Department of Geodesy and Geomatics, Zanjan University, Zanjan, Iran.
    Evaluation of robust techniques in suppressing the impact of outliers in a deformation monitoring network – A case study on the Tehran Milad tower network2007In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 42, no 4, p. 449-463Article in journal (Refereed)
    Abstract [en]

    The problem of handling outliers in a deformation monitoring network is of special importance, because the existence of outliers may lead to false deformation parameters. One of the approaches to detect the outliers is to use robust estimators. In this case the network points are computed by such a robust method, implying that the adjustment result is resisting systematic observation errors, and, in particular, it is insensitive to gross errors and even blunders. Since there are different approaches to robust estimation, the resulting estimated networks may differ. In this article, different robust estimation methods, such as the M-estimation of Huber, the “Danish”, and the L 1-norm estimation methods, are reviewed and compared with the standard least squares method to view their potentials to detect outliers in the Tehran Milad tower deformation network. The numerical studies show that the L 1-norm is able to detect and down-weight the outliers best, so it is selected as the favourable approach, but there is a lack of uniqueness. For comparison, Baarda’s method “data snooping” can achieve similar results when the outlier magnitude of an outlier is large enough to be detected; but robust methods are faster than the sequential data snooping process.

  • 87.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering. Royal Institute of Technology, Stockholm, Sweden.
    Mehdi, Najafi-Alamdari
    KN Toosi University of Technology,Tehran, Iran.
    Perturbations in orbital elements of a low earth orbiting satellite2007In: Journal of the Earth and Space Physics, Vol. 33, no 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

    The main point of this paper is to evaluate the perturbations in orbital elements of a low Earth orbiting satellite. The outcome of a numerical orbit integration process is the position and velocity vectors of satellite in an inertial coordinate system. The velocity and position vectors are converted into the corresponding orbital elements. Perturbations in a satellite motion affect the orbital elements in the sense of Keplerian motion. In this paper after introducing the perturbing forces acting on a satellite, the method of converting the position and velocity into the orbital elements is presented, and finally the perturbations in orbital elements of the low Earth orbiting satellite of CHAMP are evaluated. The numerical results show that, disregarding the geopotential perturbing forces, the air drag is the most predominant among other perturbing forces: rotational deformation, solar radiation, third body effect, solid Earth tide, ocean tide, and general relativity arranged by their magnitude respectively.

  • 88.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Mohsen, Romeshkani
    Islamic Azad University, Qazvin Branch Iran.
    Determination of sub-lithospheric stress due to mantle convection using GOCE gradiometric data over Iran2015In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 122, p. 11-17, article id 2807Article in journal (Refereed)
    Abstract [en]

    Sub-lithospheric stress due to mantle convection can be determined from gravimetric data based on Runcorn’s theory. In this paper, the satellite gradiometric data of the recent European satellite mission, the Gravity field and steady-state Ocean Circulation Explorer (GOCE) is used to determine the sub- lithospheric stress locally in Iran. The method of S function (SF) with numerical differentiation is developed further and an integral equation connecting satellite gradiometric data to SF is presented. The integral equation will be used to invert the real gradiometric data of GOCE to recover the SF. Later on, the sub-lithospheric shear stresses, which are the northwards and eastwards derivatives of the SF, are computed numerically. Our numerical results show that the mean square error of the recovered SF is smaller than the values of the SF meaning that the recovery process is successful. Also, the recovered stress has a good agreement with the tectonic boundaries and active seismic points of the world stress map (WSM) database. This stress reaches amplitude of 100 MPa in the territory.

  • 89.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Tenzer, Robert
    University of West Bohemia Plzen,New Technologies for the Information Society (NTIS), Czech Republic.
    Lithospheric stress tensor from gravity and lithospheric structure models2017In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 174, no 7, p. 2677-2688Article in journal (Refereed)
    Abstract [en]

    n this study we investigate the lithospheric stresses computed from the gravity and lithospheric structure models. The functional relation between the lithospheric stress tensor and the gravity field parameters is formulated based on solving the boundary-value problem of elasticity in order to determine the propagation of stresses inside the lithosphere, while assuming the horizontal shear stress components (computed at the base of the lithosphere) as lower boundary values for solving this problem. We further suppress the signature of global mantle flow in the stress spectrum by subtracting the long-wavelength harmonics (below the degree of 13). This numerical scheme is applied to compute the normal and shear stress tensor components globally at the Moho interface. The results reveal that most of the lithospheric stresses are accumulated along active convergent tectonic margins of oceanic subductions and along continent-to-continent tectonic plate collisions. These results indicate that, aside from a frictional drag caused by mantle convection, the largest stresses within the lithosphere are induced by subduction slab pull forces on the side of subducted lithosphere, which are coupled by slightly less pronounced stresses (on the side of overriding lithospheric plate) possibly attributed to trench suction. Our results also show the presence of (intra-plate) lithospheric loading stresses along Hawaii islands. The signature of ridge push (along divergent tectonic margins) and basal shear traction resistive forces is not clearly manifested at the investigated stress spectrum (between the degrees from 13 to 180).

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  • 90.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Zoghi, Sedigheh
    Division of Geodesy and Satellite Positioning, Royal Institute of Technology (KTH), Stockholm, Sweden.
    Local error calibration of EGM08 geoid using GNSS/levelling data2016In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 130, no July, p. 209-217Article in journal (Refereed)
    Abstract [en]

    The geoid error, computed from EGM08, is unrealistically large due to the continuation of the spherical harmonic coefficient errors down to the surface of the reference ellipsoid. In this study, we try to calibrate such an error by the differences between the EGM08 and GNSS/levelling geoids over Fennoscandia. We use the variance component estimation procedure through combined adjustments of the geoid and GNSS/levelling heights using corrector surfaces of 4-, 5- and 7-parameter. We also develop a simple iterative method to calibrate the geoid error from the a posteriori variance factor and the errors of GNSS/levelling geoid. Our numerical investigations show that performing the separate adjustment and variance component estimation for each country with a two-component stochastic model is more successful than performing it in the whole area with a five-component model. The number of GNSS/levelling data over Sweden and Norway are much larger than those in Denmark and Finland. This causes that the corrector surfaces are fitted better in these countries and consequently the estimated errors for the geoid become larger than what they should be in the others. Based on a 7-parameter corrector surface model, the average error of the EGM08 geoid becomes 12, 17, 51 and 34 mm, in Sweden, Denmark, Norway and Finland, respectively. If the two-component stochastic model is used in a combined adjustment over Fennoscandia this average error will be 48 mm.

  • 91.
    Evonson, Joel
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hansson, Josefin
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    En kartläggning av Lantmäterimyndighetens granskningsroll: Med fokus på grundkarta och fastighetsförteckning2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Till följd av propositionen 2013/14:126 En enklare planprocess har det sedan årsskiftet 2015 inträtt två nya paragrafer i lagen gällande Lantmäterimyndighetens granskningsroll i detaljplaneprocessen, vilka berättar vad Lantmäteriet ska granska och samråda om.

    När detaljplaner upprättas bygger plankartan på en grundkarta. Att det kan finnas brister i grundkartorna är ett allmänt känt problem inom Lantmäteriet men huruvida kommunerna känner till problemet är oklart. astighetsförteckningen som ska redovisa fastigheter, samfälligheter och dess rättigheter som påverkas av detaljplaneförslaget, kan grunda sig på bristfälligt material och därmed vara ofullständiga.

    Studiens syfte är att kartlägga huruvida reglerna om Lantmäteriets nya granskningsroll har haft något genomslag. Studien ska även besvara om det under granskningsprocessen uppmärksammas några brister i grundkarta och fastighetsförteckning. För att besvara frågorna utfördes åtta kvalitativa intervjuer inom Västra Götaland län med personal från Lantmäteriet och kommunala planenheterna.

    Studien har visat att de nya paragraferna inte har förändrat plangranskarnas arbetssätt, med undantag från att de nu även ska agera råd vid utformning av exploateringsavtal. I övrigt arbetar plangranskarna på samma sätt som innan reglerna kom. För planförfattarna har de nya reglerna inte inneburit någon märkbar skillnad. Angående granskningen av grundkarta och fastighetsförteckning är den begränsad. Samtliga planförfattare svarade att de alltid tar sig granskarnas yttranden. Dock är det inte alltid problemen rättas till. I tre av fyra fall var planförfattarna medvetna om att brister i grundkartan förekommer. Fastighetsförteckningen upplevdes sällan vara felaktig, två av fyra planförfattare svarade att de hade förekommit brister.De skillnader som påvisade mellan hur de kommunala och statliga Lantmäterierna utför sin granskning är att de kommunala Lantmäterimyndigheterna har ett nära samarbetet

    med de kommunala planavdelningarna och är en del av planprocessen. På de kommunala Lantmäterimyndigheterna gör de fastighetsförteckningar och därför granskas inte dessa av en tredje part.

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  • 92.
    Ewenborg, Linus
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Hellgren, Marcus
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    3D-objekt i Sverige: var och varför?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since a number of years, it is possible to form so called 3D-objects in Sweden. It is three- dimensional properties that represent closed volumes and is thus separated both horizontally and vertically. It is in contrast to traditional real estate with only horizontal boundaries (on the ground) and lacks demarcation up and down. The property types that fall under the category of 3D-objects is 3D-properties, condominiums and 3D- communities.

    This study was aimed to geographically identify the number of 3D-objects in Sweden and the distribution of 3D-object's uses and explain the advantages and disadvantages of three- dimensional property entails based on opinions from professional actors. The survey is about these professional actors view on 3D-objects and not an objective valuation from the writers.

    To implement the study all Swedish 3D-objects were identified in number by municipality and uses by county, which was based on the extraction of 3D-objects in the land registry. The mapping of the number served as a basis for selection of 20 municipalities to a survey which sought through contact with surveyors and developers working in the field examine their thoughts about the pros and cons three-dimensional property entails.

    From the mapping, it was clear that 3D-properties (those that are not condominiums) are formed in municipalities with larger cities such as Stockholm, Gothenburg and Malmö, which could be explained by the larger population in these cities. Condominiums are not as tied to urban areas, several smaller municipalities have numerous condominiums which make up a rather large portion of the total number. In communities that have large number condominiums they are most often formed in few units with large numbers in each. Many condominiums are located near the Norwegian border in communities such as Tanum, Dals-Ed and Sotenäs where they meet a norwegian demand. That communities such as Kristianstad and Örnsköldsvik has got condominiums can't be explained more than it has happened randomly and they stand out in the statistic because of the low total number of condominiums. 3D-communities have proven to be a rare phenomenon of which only a few exist today and are formed exclusively in connection with condominiums. The 3D-objects formed are mostly centered to the same area, which is located in the municipal seat. The mapping over use showed that condominium units and rental units are by far the most common uses of 3D-objects. Of 1643 3D-objects in Sweden 930 of them are condominium units and 487 rental units, which represent 87 % of the total.

  • 93.
    Falck, Thedor
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Eliasson, Thord
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Regionala skillnader i anslutningen till gemensamhetsanläggningar: Med fokus på 42 a och 43 § i anläggningslagen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since 1973, when the Swedish equivalent to the joint facilities act (anläggningslagen [AL] 1973:1149) was signed into law, co-owners of jointly owned facilities have had the ability to enter, exit or change their properties share in these facilities by themselves through a mutual agreement. This agreement must be approved by the Swedish National Land Survey (Lantmäteriet), and is used for avoiding an otherwise necessary, though costly and time consuming, reappraisal of the entire facility, in accordance with AL § 35.

    In 1998 AL was changed to include § 42 a, which now allowed surveyors to decide who should enter, exit or change shares. This is done within a land survey ordinance and only for pre-existing joint facilities.

    Both sections of the law act as measures used instead of reappraisals. Usually, an agreement between property owners is the preferred method during land surveys, but Swedish law dictates that the cheapest, most efficient alternative is to be chosen at all times. The purpose of this essay is to map out whether or not there are any regional differences in the usage of § 42 a and § 43, as well as any potential reasons as to why this happens. The essay is also meant to give a glimpse into if the co-owners of these facilities are reimbursed, as well as what type of joint facilities are usually subjected to these changes in members and shares. The bulk of this investigation has been done using a combination of quantitative research and legal methodology, with some elements of qualitative research. All executory acts containing a decision based on § 43 or § 42 a between 1998 and 2014 from 11 counties have been included in the resulting statistics. Out of these acts, 221 of them have been subjected to closer investigation in order to answer questions relating to reimbursement and facility management, as well as type of joint facility.

    The results show a large difference in what section is favoured by what county, as well as differing approaches to these sections between municipalities. As an example, 69 % of all executory acts in Västra Götaland between 1998 and 2014, where these sections where applied, used § 43. Meanwhile, In Stockholm County, 66 % of the acts within the same time period applied § 42 a. The surveyors in the municipalities within the counties gave entirely different reasons for why they work in the manner of which they do: Surveyors in Gothenburg claims that they wish to "encourage understanding" (and therefore agreements), meanwhile, surveyors in Stockholm claimed that all they do depends upon the specific circumstances of the case in question. Reimbursements were deemed unusual, only 26 % of all acts contained demands for it, regardless of which section was used. The type of joint facility was also very uniform, 70 % of them were primarily formed to manage jointly owned roads.

    The reasons for why these regional differences occur are still unclear. The suspicion is a tradition within each county, where different cultures within the offices dominate and result in different approaches to each section of the law. A larger investigation into the matter with a greater focus on qualitative research, interviews with surveyors and inquiries into different surveying offices is needed to confirm this.

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  • 94.
    Filo, Philip
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Lindstrand, Niklas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Younis, Yousif
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Framtagning av kursmaterial kring reservkraft, inriktning UPS2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis showcases the production of courseware which will be used by the engineer students within the course Industriella Elanläggningar (en. Industrial electrical facilities), IEL400. The contents will be used for the creation of a compendium for use as courseware. The thesis is oriented towards the subject UPS – a subtopic within standby power.The purpose of this thesis is to broaden the available courseware which is needed when the students of IEL400 are to design an electrical facility including a standby power supply. The courseware will be presented in the form of a compendium assembled from this thesis. UPS, short for Uninterruptible power supply, is a standby power supply that can power the load in the event of problem on the incoming power, primarily power outage. This way, many problems can be avoided, problems such as damage to property and people, loss of valuable information etc.

  • 95.
    Forsberg, Anna
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Olausson, Lisa
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Gemensamhetsanläggning: Fastighetsrättsliga problem när mark försvinner på grund av erosion2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gothenburg City is in a big development phase where a lot will happen the next years to meet the City’s future need. The old shipbuilding industry in Eriksberg has been transformed into a flourishing residential area belonging to a popular place to settle in the city. Many of the public areas in Eriksberg are attended by the property owners as jointly-owned facilities. The fact that the houses are located next to the sea makes the area attractive but at the same time it also means a climate which effect the environment. In the area it is high risk of erosion and today has the ground in some places erode away and given damage on jointly-owned facilities.

    The purpose of this study is to investigate the legal implications when the ground under a joint-owned facility eroding away. The problem is new and to keep joint-owned facility as an attractive way to corporate for common needs and develop areas next to water it is of interest to investigate in this problem. In order to investigate the legal implications has a case study been done, where the legal method mainly has been used. The case study has been made over Eriksberg where the problem first was highlighted. The result of the study is a product of subjective interpretation of the authors. Legal case and former studies concerning the subject strengthens the author's interpretation and the study's credibility.

    The study shows that the conditions surrounding a joint-owned facility should be properly investigated in order to assess the legal implications. The study has resulted in significant aspects to investigate the question is whether there is any agreement about positive achieve-ments, where the line between construction and real estate are and how the land under the facility is built. In order to prevent future disputes about the problem requires a strict work process in the establishment of joint-owned facilities and clear construction decision. The study concludes that the positive achievements of the easement should be avoided and that the neighbour law rules should apply to the parties involved in a joint facility. This means that there is a responsibility to prevent nuisance to their neighbours. Failure to follow the law is an obligation to be accountable for the damage suffered. A municipality has a responsibility to control land use in the most appropriate manner, the neglect from this municipality can be held liable for damages. Swedish surveying authority has a responsibility to act and advise in the selection of land and its principal responsibility.

  • 96.
    Franzon, Anna
    et al.
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Kristina, Lindqvist
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Enskilt huvudmannaskap för allmän plats: En studie av kommunernas redovisning av särskilda skäl2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since the Planning and Building Act (ÄPBL) was imposed in year of 1987 it has been possible to make a deviation from the main rule about municipal mandate in local plans and instead exert private responsibility for public areas. To be able to use private responsibility for public areas special reasons are required and therefore needs to be well justified in the plan description since the property owners must assume the responsibility for construction, operation and maintenance of the public areas.The purpose with this study is to map in which extent special reasons has been stated as a reason for private responsibility for public areas in local plans and if so, analyze if these special reasons conform with what’s been said in preparatory work and present case law. The study will also answer how well the plan description show who’s responsible for the development of public areas to secure the administration of these. To seek the answers to these questions a combination of juridical, quantitative and qualitative methods have been used. All municipal websites have been reviewed and resulted in 173 local plans from 85 municipalities.

    The result of the study shows that the variety of how private responsibility for public area in local plan is represented is large and in many cases deficient.How many local plans that are missing accounting of respective questions are presented below:

    Special reasons for private responsibility for public areas: 48 % of the local plans and 55 % of the municipalities

    Responsibility for development of public areas, roads: 35 % of the local plans

    Responsibility for development of public areas, nature: 52 % of the local plans

    Responsibility for the application for a joint facility: 46 % of the local plans

    The study shows that municipalities with a population of <30 000 residents use private responsibility for public areas in greater extent than others. The study also shows that municipalities with multi-party governance are the ones that practice private responsibility for public areas in a greater extent. No connection between a good and a bad accounting of special reasons and how the accounting of the implementation issues is made have been found. To sum up we can conclude that many of the local plans does not meet the legal requirements in PBL, this involves risks that it will be difficult for the public to understand the consequences of a local plan.

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  • 97.
    Freiholtz, Henrik
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Portabelt verktyg för testning av nätverkstjänster2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Networks of today employ a number of different services developed to support functioning infrastructures. In most cases, well established and functioning solutions exist for setting up a production server for any of these services, but for other purposes the market looks quite different. If you are looking for simple applications tailored for ease of use and quick deployment the selection is narrow. In order to solve this, a tool was developed, intended to be used for teaching, troubleshooting and temporary solutions, focusing on simplicity and portability. A list of requirements was created, according to which the tool was designed. The tool was to include the services DHCP, DNS, NTP, web and syslog. The tool was implemented as an x86 desktop application based on the Electron platform. The application uses a graphical user interface and is divided into modules, each of which represents a protocol. Each module is started individually and includes a few basic features from each protocol. A number of tests were created and implemented in order to verify that the application was built according to the established requirements. The test results showed that the application was built according to design and satisfied the requirements. The result was a tool that succeeded in partially filling the gap that existed in the market for tools designed for simplicity and ease of use.

  • 98.
    Grahn, Peter
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Överföring och frigörande av fastighetstillbehör: Skillnader i användandet av frigörande och överföring av fastighetstillbehör inom förrättningsverksamheten2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden consists of over 3.2 million real properties and an even greater number property accessories such as buildings and facilities. The majority of the properties are located directly on the ground. In addition three-dimensional real estate properties exist. These are situated below or under the ground level, making it possible to several layers of real properties that are vertically distributed.

    The community is continuously progressing through development of properties that are being newly created and transformed. One imperative part of the government controlled real estate development is to strive to achieve the highest and best use for each parcel of land. A facility could be included as part of a property accessory to a property, which prior to the legislative amendment in 2002, only could be transferred if it was removed from the main property. After long time of pressure from the citizens, the government decided to proceed and appoint a legal task force to investigate if a legislative amendment could be beneficial separating a property accessories from main properties. The legislative amendment was executed Jan 1st 2002 and provided a completely new possibility to transfer and to release property accessories.

    In order to investigate what the underlying bias was, the ordinance acts was reviewed and notes were taken regarding whom had requested the measure. In conjunction to the statistical analysis, five interviews were conducted. The interviews served to provide a better understanding to how the quantity surveyors experienced the legislation. In addition, data that were not recorded in the acts, were collected through the interviews.

    The result shows that cadastral surveyors are experiencing that the majority of the real estate developers are not aware how to, transfer, and to release, property accessories from the main properties. In most cases, the quantity surveyor will need to inform and teach the real estate developer about the possibility. Neither does the quantity surveyors experience it to be complicated to use the legislative tool. The shortcoming lies within the single individual professional that does not possess the knowledge of how to use the tool.

  • 99.
    Gröning, Tomas
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Är NIT-studenterna bättre än företags It-tekniker på IPv6?2016Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to find out whether the Network Technology and IT-security students is better at IPv6 than the corporate technicians. The result has been determined using a multiple-choice test that compares the knowledge between the corporate IT-technicians and the NIT students. Interviews were made with a spokesperson at each of the three companies to see how or if they make use of IPv6 and how that effects their IPv6 knowledge. The results show that the NIT students performs better than the corporations’ IT techni-cians and that none of the companies are using IPv6 in their daily work and doesn’t get any education in the subject.

  • 100.
    Gunnarsson, Alexander
    University West, Department of Engineering Science, Division of Computer, Electrical and Surveying Engineering.
    Från rutnätszoom till genetisk algoritm vid optimering av dyra funktioner2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    D. Lindström has developed an algorithm for optimization of expensive functions which is based on response surface methodology which means that a model of the expensive function is created. To optimize the response surface the algorithm is making use of a grid zoom. This grid zoom is replaced by a genetic algorithm which is based on biological evolution. Measurements are done before and after the modification focusing on CPU time. A vectorization of the code is also performed.

    Expensive functions often appear in the real world. An expensive function could be to run a simulation with certain settings to see how good they are. Because the simulation takes a long time to run you can't just try everything but instead need to strategically select which parameters to test. This it what Lindströms algorithm does.

    The results show that the grid zoom was more effective than expected but that it is ineffective in higher dimensions.

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