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  • 1.
    Adolfsson, Sofia
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Lööf, Karin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ört Dahlen, Marie
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Sätts hyresgästen i fokus?2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this examination is to study and analyze whether two different housing companies in Trollhättan, Sweden, put their tenants in focus or not. Literature based on facility management, with emphasis in customer orientation and service management, has been used to enhance the authors’ knowledge base. Interviews with the chosen housing companies and questionnaires targeted to tenants have been implemented to proceed and to answer the general question of this examination. A comparison between the housing companies will evaluate if there is any difference between a company for public utility, Eidar, and one whom is owned privately, Lundqvist. The results of the data shows, from some angles, a great variation in tenants’ opinions considering their experiences regarding having a safe home, being taken seriously by their housing company and the possibility to suit their apartment along with personal wishes and/or needs. The main question is if the tenant feels him being in focus by the housing company. The analysis illuminates and discusses the results, which will lead to a conclusion. According to this study housing companies only partly keep their tenants in focus and the utility company seems to be less focused on the customers than the private-owned one.

  • 2.
    Andersson, Anna-Karin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Kringtjänster vid fastighetsförmedling: En studie av konsekvenserna med nya fastighetsmäklarlagen2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Projektet syftar till att klargöra hur den nya fastighetsmäklarlagen ifrån 2011 har mottagits och vilka konsekvenser den har fått för mäklarnas arbete, när det gäller kringtjänster. Mäklarens arbete har inte förändrats på något radikalt sätt. Tidigare fanns ett arbete med kringtjänster vilka inte fick erhållas arvode för medan det efter lagändringen är möjligt med ersättning. Denna får däremot, enligt den nya lagen, endast vara obetydlig.

    Målet med projektet var att ge svar på ett flertal frågeställningar. Att undersöka hur lagen utfallit avseende utbud och efterfrågan av kringtjänster samt utreda om skillnader finns i omfattning av utbud och användande utav kringtjänster vad avser storstad – landsort? Dessutom undersöktes antalet prövade tillsynsärenden och branschens syn på framtiden.

    För att utreda frågeställningarna användes den deskriptiva metoden i kombination med den sekundära informationen. Detta för att beskriva och förklara bakgrunden och vilket synsätt branschen haft på frågan om kringtjänster tidigare. För att nå den primära informationen och utreda vilka åsikter och tankar som nu finns gällande kringtjänster användes kvalitativa frågor i samband med att utvalda branschrepresentanter intervjuades. Fastighetsmäklarförbundet (FMF) och Mäklarsamfundet intervjuades för att få en övergripande bild av marknaden. De mäklarbolag som intervjuades, valdes för att de antingen var bland de största i landet eller hade någon knytning till kringtjänstsamarbeten.

    Branschen har tagit emot lagändringen på olika sätt. Till exempel får Bjurfors mäklare inte själva del i den ersättning som tillfaller företaget för de kringtjänster som förmedlas utan ersättningen går till administrationen av kringtjänsterna. Länsförsäkringar fastighetsförmedling tar inte ut någon ersättning när det gäller de samarbeten och tjänster de förmedlar. Övriga använder sig av kringtjänsteersättningar i varierande mängd. Branschorganisationerna har skilda utgångspunkter i flertalet frågor och olika synsätt. FMF var när förslaget kom, emot att ersättning för kringtjänster skulle tillåtas och Mäklarsamfundet arbetade för förslaget. FMF förhandlar vissa tjänster som är nära knutna till mäklaryrket åt sina medlemmar, medan Mäklarsamfundet har avvecklat de produkter som de haft. Fastighetsmäklarnämnden har ännu inte prövat något tillsynsärende gällande hantering av kringtjänster och de oklara ersättningsanvisningarna utifrån den nya fastighetsmäklarlagen. 

  • 3.
    Björking, Sofia
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Tjulander, Jennie
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Etablering av vindparker på arrenderad mark: En studie av markåtkomst för vägar2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The expansion of wind power in Sweden has increased at a rapid pace in the recent years. Between the years 2008 – 2011, the productions of electricity from wind power were increased by 209%. During 2011, this corresponded to an energy production of 6,1 TWh, which suggests that Sweden is in a good phase to achieve the environmental objectives, adopted by the Parliament. The objectives purpose is that the production in 2020 will amount to 30 TWh.

    When a wind farm is to be establish a well-executed project is of great importance for achieving profitability and minimize the risks in the project.  The different phases of the project includes an important pre-planning where the conditions for establishment are investigated, the planning with consultation and preparation of an environmental assessment, the application of needed authorizations and permissions, procurement of works and construction works and the final construction where roads and wind turbines are constructed and power lines connects to the mains. This thesis provides a general model for how to proceed and what factors should be considered in the establishment of wind farms.

    The purpose of this thesis is to investigate how the right of roads can be ensured in the case when the wind park shall be established on leased land. The question is important and needs to be solved in order to construct, maintain and decommission the wind turbines.

    When lease tenure is hold, the lessee in the contract usually gives the right to use and construct roads within the leased area. Outside the leased area it’s not always as obvious how the right of roads should be ensured. Usually needs widening and strengthening of the existing roads that will be used as well as new roads are to be constructed.

    Depending on the circumstances and requirements of the particular case, tenancies, joint facility, easements or expropriation can be present in order to secure the right of roads. The factor of most importance for when the options can be used is if the wind park is built

    or not. Since the wind power company in a lease case doesn’t own any property only tenancies can be used when the wind park isn’t built. If the property owners oppose the measure it’s also possible to forcibly expropriate tenancies. When the wind park is built it’s also possibly to enter into a joint facility or grant an easement. These can be applied both when the property owners are in favor of the action, but also in some cases without their consent.

    This thesis investigates the various options, their meaning and applicability to finally be analyzed and summarized. 

  • 4.
    Bäckman, Caroline
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Lorentzon, Malin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    GIS-applikationer i smartphones och till surfplattor2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The intention of this work is to describe whether and how municipalities and municipal companies make use of mobile GIS-apps in their daily work. It will also give a general description of how the technology works and what the market looks like.

    Right now the use of Smartphones is increasing with the public and even companies have started buying smartphones to their offices. The sale of Tablets has also increased and is expected to increase even more in the next few years. This means that the market for applications have increased considerably. The use of mobile GIS-apps by municipalities and municipal companies seems to be rather small right now but the interest is growing all the time. Of those who responded to our questionnaire the majority said that they would be willing to use mobile GIS-apps and that they were interested in developing their own applications specialized for their needs.

    The technology is developing very rapidly right now and new models of both smartphones and tablets are constantly on the market. The models are more durable and more powerful but as yet there is some way to go before they catch up with the rugged PC in terms of functionality.

    Right now not many of the municipalities and municipal companies that have answered our questionnaire are using mobile GIS-apps often in their daily work. This appears to be because the information about what applications are available and how to use them do not reach out to the organizations. The fear that the devices that the applications are used on will not be good enough for fieldwork is also one of the reasons why other methods are chosen.

    What we have found after compiling the questionnaire and conducted two telephone interviews is that municipalities and municipal corporations are interested in mobile GIS-apps and want to embrace the technology but do not yet know how.

  • 5.
    Börjesson, Sofie
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Wikman, Emelie
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Geografiska informationssystem som analysverktyg av kommunal planering: En studie om markinnehav i Kungälv-, Lysekil- & Skövde kommun2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since 1900, a large population increase has occurred in Sweden, which has led to the importance of strategic planning for society's continued development. The latest municipal reform, of 1970-71, led to larger municipalities with increased responsibility. Municipalities now started to work actively with community planning issues and no legal differences were to remain. Today, municipal development occurs at different rates, partly depending on geographical location and resources, but also because there is no regional mechanism that controls how municipalities are working with land issues. In connection with "Väröfallet, in 1963, attention was drawn to the fact that physical planning was eclipsed by economic interests. After that event, people became aware of environmental issues and fear of environmental damage on earth increased. During the time of "Väröfallet" municipalities began working more actively with environmental issues, but it was not until 1999 that the government adopted 15 goals to regulate environmental quality which later, in 2005, became 16 goals. Environmental quality objectives are regulated by "Miljöbalken". The objectives were to promote sustainable development and national interests to protect biodiversity. The purpose of this study is to compare the landholdings of three municipalities and how the use of them has been affected since the last municipal reform. The methods used in the study are qualitative and quantitative. The quantitative section consists of a concrete mapping program, ArcMap, which provided map data from each municipality as well as a previous study course. Map production is an important step in analyzing what the landholdings looks like as well as the distribution of national interests within the municipalities. The qualitative part of the study consists of interviews with municipal representatives who informed us about the facts surrounding land issues and planning strategy. The study also investigates whether there is a regional system that controls the way in which they work. The result of the produced maps shows urban land holdings, national interests as well as private landowners of importance. Part of the result is an analysis of the area on the maps made using GIS tools to show how much municipal land and industrial land covered by national interests. Another part of the result is to visually see local conditions for future development.

    The maps were analyzed using GIS tools to measure similarities, differences and local conditions for future development. Summary local governments should actively work with GIS tools as an aid in the control of land use. Through GIS, municipalities can keep updated and see how changes in the municipality take place over time. The conclusion of the study is that local governments must work strategically to develop a sustainable society

  • 6.
    Carlsson, Emma
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Almqvist, Åsa
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Gränspunkter i Trollhättans Stads databas2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, we have studied the boundary points that are created by ordinances and documented in the coordinate system that are no longer relevant to use. We have studied the chain that includes measuring of the current boundary points, transformation of the coordinates into current coordinatesystem and until the boundary points are introduced into the database of Trollhattans Stad.

    We have worked with three different areas in Trollhättan, which are Skoftebyn, the center area and Kalltorps By. They are generated at different times areas, there are different types of settlements in the different areas, and they are set in different coordinate systems. Through our work we have observed that different areas in Trollhättan have variety preserved boundary markers. In residential areas that we studied, the majority of the markers were found, while in the center area the boundary points were non-existent, except for the boundary markers expelled with "house corners".

    To get a deeper context, we conducted a retrospective, where we studied the property boundary in an ordinary way. We have also interviewed Roger Johansson, Trollhattans Stad, to obtain information about the measurement history of Trollhattans Stads.

    Preparation for survey of boundary points was done by ordinance acts that was reviewed to obtain information on property boundaries and which method of marking that was used. Survey of the boundary markers was performed with GPS and then transferred into TopoCad 14.

    The border points of ordinance file transformed from the original executor system SWEREF 99 and then transferred into the database. The approach for coordinate transformations and how the introduction of boundary points in the database was done, are fully documented.

    The comparison of the radial deviations and surveying levels of 5cm in urban areas and 10 cm in rural areas shows that highly accurate entries will be required to include all border points in the database of Trollhättan Stad.

  • 7.
    Eklund, Kristin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Detaljplan och naturreservat: En jämförelse mellan två kommunala processer2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reasons as to why nature should be protected and preserved can be explained in its environmental value, cultural value or its value for recreation and outdoor life. According to Swedish legislation valuable nature are of national interest and needs to be protected from various interference like urban planning. Municipalities can protect and preserve valuable nature with the help of two different plans, a development plan or by proclaiming the area a nature reserve.

    This study aims to compare the development plan with the plan for a nature reserve and to find differences and similarities between the two processes. This to answer the question whether Swedish municipalities should use a development plan or a nature reserve when preserving nature sites. The study will use a legal method which involves the usage of legal sources like constitutions and its preparatory work, case-law and legal doctrine.

    As expected, the study shows that the municipalities should protect nature through a nature reserve. The goal of a nature reserve is protecting nature and thus have a focus towards nature and environmental questions. However, besides the obvious, this study has shown that preserving nature through a nature reserve is much more beneficial, both for landowners and for the municipality itself. The landowners participate more in the decision making of a nature reserve than in a development plan. Financially it is also more beneficial since the environmental code, when compared to the planning and building act, has better financial compensation for the restrictions of land usage put on the landowners. For municipalities the benefits can be seen in the fact that the workload with the nature reserve can be constrained to environmental questions and that the municipalities can get state funding. A nature reserve also gives a much stronger protection which ensures the municipalities action if a shift in power would come in place

  • 8.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    An integral approach to regional gravity field refinement using Earth gravity models2013In: Journal of Geodynamics, ISSN 0264-3707, E-ISSN 1879-1670, Vol. 68, p. 18-28Article in journal (Refereed)
    Abstract [en]

    The idea of this paper is to refine the terrestrial gravimetric data with the Earth's gravity models (EGMs) and produce a high quality source of gravity data. For this purpose, biased and unbiased integral estimators are presented. These estimators are used to refine gravimetric data over Fennoscandia with the ITG-GRACE2010s and GO_CONS_GCF_2_DIR_R2 EGMs, which are the recent products of the gravity field and climate experiment (GRACE) and the gravity field and steady-state ocean circulation explorer (GOCE) satellite missions. Numerical results show that the biased integral estimator has smaller global root mean square error (RMSE) than the unbiased one. Also a simple strategy is presented to down-weight the low-frequencies the terrestrial data in spectral combination. The gravity anomalies, computed by EGM08, are compared to the refined anomalies for evaluation purpose. In the case of using a cap size of 1° for integration the EGM08 gravity anomalies are more correlated with the refined ones. Also the band-limited kernels can simply be generated to maximum degree of the used EGMs for both estimators. Comparisons of the combined anomalies and those of EGM08 show insignificant differences between the biased and unbiased estimators in practice. However, the biased estimator seems to be proper one for gravity data refinement due to its smaller global RMSE.

  • 9.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Determination of Moho Discontinuity from Satellite Gradiometry Data: Linear Approach2014In: Geodynamics Reseach International Bulletin, ISSN 2345-4997, Vol. 1, no 2, p. 1-13Article in journal (Other academic)
    Abstract [en]

    The satellite gradiometry data (SGD) can be used for studying the crustal structure in addition to the Earth’s gravity field. This paper will show how this type of data is related to the Moho discontinuity or the boundary between the Earth’s crust and mantle. Here, the Vening Meinesz-Moritz (VMM) theory of isostasy is used and its mathematical formulae are modified to use the SGD instead of the Earth gravity models. A linear integral equation with a well-behaving kernel is presented by approximating the Moho depth formula derived based on the VMM theory. The error of this approximation is less than 300 m in Iran as the study area. Furthermore, this paper shows that the contribution of the higher degree harmonics than 215 is less than 1% with respect to the total signal of Moho undulations. This means that the use of SGD is meaningful as they sense the harmonics of the Earth’s gravity field to this degree. Two methods of one-step and two-step are proposed for Moho determination and applied in Iran.  It is shown that to reduce the effect of spatial truncation error of the integral formulae of both methods the central area should be smaller by 6 than the inversion area. Numerical studies show that the two-step approach is superior to the other one and the root mean squared error of differences between the Moho model recovered by an Earth gravity model and SGD is about 1.5 km in Iran.

  • 10.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    From satellite gradiometry data to the sub-crustal stress due to the mantle convection2014In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 171, no 9, p. 2391-2406Article in journal (Refereed)
    Abstract [en]

    Subcrustal stress induced by mantle convection can be determined by the Earth's gravitational potential. In this study, the spherical harmonic expansion of the simplified Navier–Stokes equation is developed further so satellite gradiometry data (SGD) can be used to determine the subcrustal stress. To do so, we present two methods for producing the stress components or an equivalent function thereof, the so-called S function, from which the stress components can be computed numerically. First, some integral estimators are presented to integrate the SGD and deliver the stress components and/or the S function. Second, integral equations are constructed for inversion of the SGD to the aforementioned quantities. The kernel functions of the integrals of both approaches are plotted and interpreted. The behaviour of the integral kernels is dependent on the signal and noise spectra in the first approach whilst it does not depend on extra information in the second method. It is shown that recovering the stress from the vertical–vertical gradients, using the integral estimators presented, is suitable, but when using the integral equations the vertical–vertical gradients are recommended for recovering the S function and the vertical–horizontal gradients for the stress components. This study is theoretical and numerical results using synthetic or real data are not given.

  • 11.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    From tensor to vector of gravitation2014In: Artificial Satellites, ISSN 2083-6104, Vol. 49, no 2, p. 63-80Article in journal (Refereed)
    Abstract [en]

    Different gravitational force models are used for determining the satellites’ orbits. The satellite gravity gradiometry (SGG) data contain this gravitational information and the satellite accelerations can be determined from them. In this study, we present that amongst the elements of the gravitational tensor in the local north-oriented frame, all of the elements are suitable for this purpose except Txy. Three integral formulae with the same kernel function are presented for recovering the accelerations from the SGG data. The kernel of these integrals is well-behaving which means that the contribution of the far-zone data is not very significant to their integration results; but this contribution is also dependent on the type of the data being integrated. Our numerical studies show that the standard deviations of the differences between the accelerations recovered from Tzz, Txz and Tyz  and those computed by an existing Earth´s gravity model reduce by increasing the cap size of integration. However, their root mean squared errors increase for recovering Tyfrom Tyz.  Larger cap sizes than 5   is recommended for recovering Tx and Tz  but smaller ones for Ty.

  • 12.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Integral Approaches to Determine Sub-Crustal Stress from Terrestrial Gravimetric Data2016In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 173, no 3, p. 805-825Article in journal (Refereed)
    Abstract [en]

    The spherical harmonic expressions of the horizontal sub-crustal stress components induced by the mantle convection are convergent only to low degrees. In this paper, we use the method of stress (S) function with numerical differentiation and present a formula for determining the degree of convergence from the mean Moho depth. We found that for the global mean Moho depth, 23 km, this convergence degree is 622 and for Iran, 35 km, it is 372. Also, three methods are developed and applied for computing the sub-crustal stress, (1) direct integration with a spectral kernel limited up to the degree of convergence, (2) integral inversion with a kernel having closed-form formula without any frequency limit, and (3) solving an integral equation with limited spectral kernel to the convergence degree. The second method has no divergence problem and its kernel function is well behaving so that the system of equations from which the S function is determined is stable, and no regularisation is needed to solve it. It should be noted that for using this method the resolution of the recovery should be higher than 0.5° × 0.5°, otherwise the recovered S function and correspondingly the stress components will have smaller magnitude than those derived from the other two methods. Our numerical studies for stress recovery in Iran and its surrounding areas show that the methods, which use the limited spectral kernels to the convergence degree, deliver consistent results to that of the spherical harmonic expansion.

  • 13.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Integral developments of Vening Meinesz-Moritz formula for local determination of Moho discontinuity and their applications in Iran2014In: Geodynamics Research International Bulletin, ISSN 2345-4997, Vol. 2, no 3, p. I-IXArticle in journal (Refereed)
    Abstract [en]

    Global models of the Earth gravity field and topographic/bathymetric data can be used for the gravimetric determination of the Moho discontinuity based on the Vening Meinesz-Moritz theory. In this paper, we mathematically develop this method in such a way that the local data can be used for Moho modelling. Two integral formulae are presented, one for integrating the data and one for their inversion. The kernels of both integrals are well-behaving meaning that the contribution of far-zone quantities being integrated are not very significant in the results. Both of these methods are applied for computing the Moho model of Iran and their results are compared to the Moho model determined based on the global models. Consistency of the computed Moho models from the simulated data and the global models verifies the correctness of both approaches. The presented methods are consistent even for the case of using real data. Numerical results show that the minimum value of the Moho models derived by the simulated data and global models are about 31 km, whilst those derived from the real data are about 3 km smaller. Similarly, the mean value of Moho depths derived from real data is about 1 km smaller than that from the global models.

  • 14.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Numerical aspects of EGM08-based geoid computations in Fennoscandia regarding the applied reference surface and error propagation2013In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 96, p. 28-32Article in journal (Refereed)
    Abstract [en]

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

  • 15.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    On the relation between Moho and sub-crustal stress induced by mantle convection2015In: Journal of Geophysics and Engineering, ISSN 1742-2132, E-ISSN 1742-2140, Vol. 12, no 1, p. 1-11Article in journal (Refereed)
    Abstract [en]

    The sub-crustal stress components due to mantle convection have a direct relation with the spherical harmonic coefficients of the Earth's disturbing potential like those of the Moho model, developed by the Vening–Meinesz–Moritz theory. In this paper, the relation between the stress components and the global and local models of Moho is mathematically developed in three different ways. Here, we present the S function (S) with a numerical differentiation approach to generate the stress components and we show that its spherical harmonic series is convergent to a degree of about 600 based on a mean global Moho depth of 23 km. An integral approach is developed for integration of a local Moho model for the stress recovery, but the kernels of this integral are not likely to be convergent and should be generated by their spectral forms to a limited degree. Another method is developed based on integral inversion, which is free of any mathematical problem and suitable for recovering S from an existing model of Moho. Our numerical presentation shows that the stress has a good agreement with the tectonic boundaries and the places at which the curvature of the Moho surface changes.

  • 16.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    On the reliability and error calibration of some recent Earth's gravity models of GOCE with respect to EGM082013In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 48, no 2, p. 199-208Article in journal (Refereed)
    Abstract [en]

    The Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission is dedicated to recover spherical harmonic coefficients of the Earth's gravity field to degree and order of about 250 using its satellite gradiometric data. Since these data are contaminated with coloured noise, therefore, their inversion will not be straightforward. Unsuccessful modelling of this noise will lead to biases in the harmonic coefficients presented in the Earth's gravity models (EGMs). In this study, five of the recent EGMs of GOCE such as two direct, two time-wise and one space-wise solution are used to degree and order 240 and their reliability is investigated with respect to EGM08 which is assumed as a reliable EGM. The detected unreliable coefficients and their errors are replaced by the corresponding ones from EGM08 as a combination strategy. A condition adjustment model is organised for each two corresponding coefficients of GOCE EGMs and EGM08; and errors of the GOCE EGMs are calibrated based on a scaling factor, obtained from a posteriori variance factor. When the factor is less than 2.5 it will be multiplied to the error otherwise the error of EGM08 coefficient will be considered as the calibrated one. At the end, a simple geoid estimator is presented which considers the EGMs and their errors and its outcomes are compared with the corresponding geoid heights derived from the Global Positioning System (GPS) and the levelling data (GPS/levelling data), over Fennoscandia. This comparison shows that some of the combined-calibrated GOCE EGMs are closer to the GPS/levelling data than the original ones.

  • 17.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. Department of Geodesy, K.N.Toosi University of Technology, Tehran.
    Spectral combination of spherical gradiometric boundary-value problems: a theoretical study2012In: Pure and Applied Geophysics, ISSN 0033-4553, E-ISSN 1420-9136, Vol. 169, p. 2201-2215Article in journal (Refereed)
    Abstract [en]

    The Earth’s gravity potential can be determined from its second-order partial derivatives using the spherical gradiometric boundary-value problems which have three integral solutions. The problem of merging these solutions by spectral combination is the main subject of this paper. Integral estimators of biased- and unbiased-types are presented for recovering the disturbing gravity potential from gravity gradients. It is shown that only kernels of the biased-type integral estimators are suitable for simultaneous downward continuation and combination of gravity gradients. Numerical results show insignificant practical difference between the biased and unbiased estimators at sea level and the contribution of far-zone gravity gradients remains significant for integration. These contributions depend on the noise level of the gravity gradients at higher levels than sea. In the cases of combining the gravity gradients, contaminated with Gaussian noise, at sea and 250 km levels the errors of the estimated geoid heights are about 10 and 3 times smaller than those obtained by each integral

  • 18.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Alizadeh-Khameneh, Mohammad. Amin
    Royal Institute of Technology (KTH), Division of Geodesy and Geoinformatics.
    The effect of constraints on bi-objective optimisation of geodetic networks2015In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 50, no 4, p. 449-459Article in journal (Refereed)
    Abstract [en]

    One of the problems in the single-objective optimisation models (SOOMs) for optimising geodetic networks is the contradiction of the controlling constraints, which may lead to their violation or infeasibility in the optimisation process. One way to solve this problem is to use a bi-objective optimisation model (BOOM) instead of SOOMs. In this paper, we will use the BOOM of precision and reliability and investigate the influence of the controlling constraints in a two-dimensional simulated network. Our studies show that the unconstrained BOOM is a good model, which almost fulfils our precision and reliability demands of the network. This model is also economical as more observables are removed from the plan whilst adding the controlling constraints leads to including more observables, which have no significant role

  • 19.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. K N Toosi University of Technology, Department of Geodesy, Tehran, Iran.
    Bagherbandi, Mohammad
    University of Gävle, Department of Industrial Development, IT and Land Management .
    Quality description for gravimetric and seismic Moho models of Fennoscandia through a combined adjustment2012In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 47, no 4, p. 388-401Article in journal (Refereed)
    Abstract [en]

    The gravimetric model of the Moho discontinuity is usually derived based on isostatic adjustment theories considering floating crust on the viscous mantle. In computation of such a model some a priori information about the density contrast between the crust and mantle and the mean Moho depth are required. Due to our poor knowledge about them they are assumed unrealistically constant. In this paper, our idea is to improve a computed gravimetric Moho model, by the Vening Meinesz-Moritz theory, using the seismic model in Fennoscandia and estimate the error of each model through a combined adjustment with variance component estimation process. Corrective surfaces of bi-linear, bi-quadratic, bi-cubic and multi-quadric radial based function are used to model the discrepancies between the models and estimating the errors of the models. Numerical studies show that in the case of using the bi-linear surface negative variance components were come out, the bi-quadratic can model the difference better and delivers errors of 2.7 km and 1.5 km for the gravimetric and seismic models, respectively. These errors are 2.1 km and 1.6 km in the case of using the bi-cubic surface and 1 km and 1.5 km when the multi-quadric radial base function is used. The combined gravimetric models will be computed based on the estimated errors and each corrective surface.

  • 20.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ebadi, Sahar
    K.N.Toosi University of Technology, Tehran, Iran.
    A strategy to calibrate errors of Earth gravity models2014In: Journal of Applied Geophysics, ISSN 0926-9851, E-ISSN 1879-1859, Vol. 103, no April, p. 215-220Article in journal (Refereed)
    Abstract [en]

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

  • 21.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ebadi, Sahar
    Department of Geodesy, K.N.Toosi University of Technology.
    Geoid modelling based on EGM08 and the recent Earth gravity models of GOCE2013In: Earth Science Informatics, ISSN 1865-0481, Vol. 6, no 3, p. 113-125Article in journal (Refereed)
  • 22.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ghorbannia, Morteza
    K.N. Toosi University of Technology, Department of Geodesy, Tehran.
    The effect of spatial truncation error on the variance of gravity anomalies derived from inversion of satellite orbital and gradiometric data2014In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 54, no 2, p. 261-271Article in journal (Refereed)
    Abstract [en]

    The spatial truncation error (STE) is a significant systematic error in the integral inversion of satellite gradiometric and orbital data to gravity anomalies at sea level. In order to reduce the effect of STE, a larger area than the desired one is considered in the inversion process, but the anomalies located in its central part are selected as the final results. The STE influences the variance of the results as well because the residual vector, which is contaminated with STE, is used for its estimation. The situation is even more complicated in variance component estimation because of its iterative nature. In this paper, we present a strategy to reduce the effect of STE on the a posteriori variance factor and the variance components for inversion of satellite orbital and gradiometric data to gravity anomalies at sea level. The idea is to define two windowing matrices for reducing this error from the estimated residuals and anomalies. Our simulation studies over Fennoscandia show that the differences between the 0.5°×0.5°0.5°×0.5° gravity anomalies obtained from orbital data and an existing gravity model have standard deviation (STD) and root mean squared error (RMSE) of 10.9 and 12.1 mGal, respectively, and those obtained from gradiometric data have 7.9 and 10.1 in the same units. In the case that they are combined using windowed variance components the STD and RMSE become 6.1 and 8.4 mGal. Also, the mean value of the estimated RMSE after using the windowed variances is in agreement with the RMSE of the differences between the estimated anomalies and those obtained from the gravity model.

  • 23.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ghorbannia, Morteza
    Department of Geodesy, K.N.Toosi University of Technology.
    The use of Gaussian equations of motions of a satellite for local gravity anomaly recovery2013In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 52, no 1, p. 30-38Article in journal (Refereed)
    Abstract [en]

    The orbital elements of a low Earth orbiting satellite and their velocities can be used for local determination of gravity anomaly. The important issue is to find direct relations among the anomalies and these parameters. Here, a primary theoretical study is presented for this purpose. The Gaussian equations of motion of a satellite are used to develop integral formulas for recovering the gravity anomalies. The behaviour of kernels of the integrals are investigated for a two-month simulated orbit similar to that of the Gravity field and steady-state ocean circulation explorer (GOCE) mission over Fennoscandia. Numerical investigations show that the integral formulas have neither isotropic nor well-behaved kernels. In such a case, gravity anomaly recovery is not successful due to large spatial truncation error of the integral formulas. Reformulation of the problem by combining the orbital elements and their velocities leads to an integral with a well-behaved kernel which is suitable for our purpose. Also based on these combinations some general relations among the orbital elements and their velocities are obtained which can be used for validation of orbital parameters and their velocities

  • 24.
    Eshagh, Mehdi
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Sprlak, Michal
    University of West Bohemia, NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, Plzeň, Czech Republic.
    On the integral inversion of satellite-to-satellite velocity differences for local gravity field recovery: A theoretical study2016In: Celestial mechanics & dynamical astronomy, ISSN 0923-2958, E-ISSN 1572-9478, Vol. 124, no 2, p. 124-144Article in journal (Refereed)
    Abstract [en]

    The gravity field can be recovered locally from the satellite-to-satellite velocity differences (VDs) between twin-satellites moving in the same orbit. To do so, three different integral formulae are derived in this paper to recover geoid height, radial component of gravity anomaly and gravity disturbance at sea level. Their kernel functions contain the product of two Legendre polynomials with different arguments. Such kernels are relatively complicated and it may be impossible to find their closed-forms. However, we could find the one related to recovering the geoid height from the VD data. The use of spectral forms of the kernels is possible and one does not have to generate them to very high degrees. The kernel functions are well-behaving meaning that they reduce the contribution of far-zone data and for example a cap margin of 7∘ is enough for recovering gravity anomalies. This means that the inversion area should be larger by 7∘ from all directions than the desired area to reduce the effect of spatial truncation error of the integral formula. Numerical studies using simulated data over Fennoscandia showed that when the distance between the twin-satellites is small, higher frequencies of the anomalies can be recovered from the VD data. In the ideal case of having short distance between the satellites flying at 250 km level, recovering radial component of gravity anomaly with an accuracy of 7 mGal is possible over Fennoscandia, if the VD data is contaminated only with the spatial truncation error, which is an ideal assumption. However, the problem is that the power of VD signal is very low when the satellites are close and it is very difficult to recognise the signal amongst the noise of the VD data. We also show that for a successful determination of gravity anomalies at sea level from an altitude of 250 km mean VDs with better accuracy than 0.01 mm/s are required. When coloured noise at this level is used for the VDs at 250 km with separation of 300 km, the accuracy of recovery will be about 11 mGal over Fennoscandia. In the case of using the real velocities of the satellites, the main problems are downward/upward continuation of the VDs on the mean orbital sphere and taking the azimuthal integration of them.

  • 25.
    Freiholtz, Maria
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Skredriskhantering i utvalda kommuner2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to identify and describe the legal framework governing local government work on landslide prevention. This purpose is supported by two issues; which legal framework municipalities have to relate to the risk of landslide management. And plan strategies used in the prevention of landslides?

    The study is restricted to only discuss three municipalities. Focus is on the time before a landslide takes place and is reported from a municipal perspective. There are two selected method, which implies both interviews of semi-structured nature and literature studies. The approaching method was to collect data, sifting of the material and the compilation of results. In the theory section four important background topics are presents and the aim is to provide a basic picture of the landslide problem in society. The interdisciplinary subjects in this study are geological conditions, historical landslides in the Göta älvdalen, climate change and geotechnic.

    The result chapter consists of two parts. The first is called Legal Framework and contains a survey of the laws that impact on landslide prevention. The laws presented are The Swedish Law of Planning and Building Act, the Law of Environmental Code, the Law on Protection against Accidents, the Law on municipalities and county measures before and during extraordinary events in times of peace and times of alert, the Law of Expropriation and the Law of Indemnity. The second part of the result is called Municipal strategies and it´s practical approach on landslide prevention. The chapter concludes with a result analysis that compiles the responses emerged. This is followed by a discussion section that contains a valuation of forward originated responses and report successes as well as shortcomings in the work. In the conclusion reported responses are coupled together with the problems presented in the beginning of the study. The underlying purpose and issues are also answered here. There is also an evaluation of past results, and reflections on what could have been done differently. Several interesting aspects not covered in this study is reported and suggested as future works. Finally, the study report sources as well as several appendices necessary to increase reader's understanding of the study

  • 26.
    Holmer, Anna
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Carlsson, Lisa
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Tomträttens värdepåverkan vid försäljning: En jämförande studie av radhus i Göteborg2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Köpeskillingen på en fastighet påverkas av flertalet faktorer, såsom läge, utbud och efterfrågan. En fastighet kan ha flera typer av upplåtelseformer, två av dem är äganderätt och tomträtt, där man vid innehav av en tomträtt betalar en årlig avgäld. Avgälden kan ses som en form av hyra till markägaren, som enligt teorin ska vara en prispåverkande faktor. Syftet med studien är att undersöka om tomträtten som upplåtelseform är en prispåverkande faktor. Samt att undersöka om det finns tydliga skillnader på tomträttens värdepåverkan vid försäljning beroende på i vilket område fastigheten är belägen. Studien är en undersökning genomförd på Lantmäteriets sammanställda data av försålda småhus av typen radhus mellan åren 2011 – 2013 i Göteborgs kommun. Det är en jämförande studie med kvantitativa beräkningar med redovisning av den procentuella skillnaden av försäljningspriserna mellan de två typerna av upplåtelseformer. Resultatet av studien visade att det är en prisskillnad mellan försålda radhus upplåtna med tomträtt och försålda radhus med äganderätt, där tomträtterna hade ett något lägre försäljningspris i de flesta studerade områden. I fem av de åtta områdena var medelpriset i kr/kvm för de försålda tomträtten lägre än för de försålda äganderätten. I sex av de åtta områdena var medelvärdet för K/T lägre för de försålda tomträtterna än för de försålda äganderätterna. Avgäldens storlek hade en liten påverkan på prisskillnaden oavsett om fastigheten var belägen i ett billigare eller dyrare område. Tomträtten kan konstateras vara en prispåverkande faktor.

  • 27.
    Johansson, Anna
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Rosenkvist, Agnes
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Landsbygdsutveckling i strandnära lägen: Länsstyrelsernas och kommunernas tillämpning av lagstiftningen2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this bachelor’s thesis is to chart and analyse how the legislation about countryside development in areas close to shores (LIS) is applied, by studying the county administrative boards in Sweden and the municipalities of Mariestad, Färgelanda, Munkedal and Mellerud. Since February 1

    st 2010, it’s possible for the municipalities to point out LIS-areas in the comprehensive plans and it’s the county administrative boards’ responsibility to look after the purposes of the shore protection, so these won’t be opposed in an unacceptable way.

    A number of county administrative boards in Sweden have written advices about how the municipalities should act when they are pointing out LIS-areas. These advices differ somewhat from each other, both according to extent and content. However, we think that several of these differences may be explained by unintended variances in the county administrative boards’ way of writing and that a trial, irrespective of which county administrative board, possibly could lead to the same result.

    It’s obvious that there is a conflict of interests between the purposes of the shore protection and LIS. The county administrative boards emphasize, in their written advices, the importance of long-term planning by the municipalities and that the LIS-areas are not to be pointed out carelessly. The municipalities, that we have been studying, have chosen a comparatively large number of LIS-areas, of which several are located by the lake Vänern. An expanded shore protection prevails at Vänern and in addition LIS should be used restrictively if there is a high interest in building.

    The municipalities planning look different and have different level of details; some have made detailed thematic additions to the comprehensive plans while some has made a comprehensive thematic planning support. In the county administration board’s utterance criticism emerges against several LIS-areas, about everything from details to the suitability of whole LIS-areas. The criticism is considered by the municipalities in varying extent, but

    BACHELOR’S THESIS

    iii

    when it comes to the LIS-areas that the county administration board finds unsuitable the municipalities often choose to keep these. This, in combination with the municipalities’ way to describing and motivate their LIS-areas, makes us question how great the possibilities are to carry through, at least in a foreseeable future.

  • 28.
    Karlsson, Amanda
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Magnusson, Jenny
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Plan- och bygglagens krav på detaljplanebestämmelser: En granskning i Skåne län2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Local authorities have the opportunity to regulate the use of land- and water areas with a detailed development plan. The restrictions of the plan are legally bound after the plan becomes final and the Planning and Building Act, chapter four regulate what a plan may include. The chapter is exhaustive, which means that only what is listed in the chapter may be regulated. The chapter also gives the restrictions clarity requirements. In the Planning and Building Act is also to be read that to plan land- and water areas is an affair that only can be done by the municipalities which gives them a planning monopoly.     

    In cases where the municipality uses provisions in a plan that doesn’t have support in the Planning and Building Act chapter four means that the current legislation is not followed. This can lead to that the credibility of the legal system decreases and also give the property owners difficulties in interpreting the meaning of the provisions.    

    Previous work has shown that the municipality uses plan provisions that are extended beyond the current legislation and in this work further 279 plans get examined to investigate whether they include unclear provisions or provisions without support in law.  

    The provisions in this study which is considered incorrect have been categorized into four different categories according to the manner in which they are considered to be deficient. One category consists of provisions that lack legal support and three categories consist of provisions that are unclear in different ways.

    The result of this survey shows that nearly half of the examined detailed development plans contain one or more provisions which don’t meet the legal requirements for clarity or are not among the enumerated provisions of the Planning and Building Act chapter four. The study also shows that unclear plan provisions are more frequent than the plan provisions that lack legal support.

    Boverket argues that the erroneous provisions shall be deemed invalid but even so, the presence of them could have consequences. The reasons for their occurrence can be many and a number of different solutions can be found, among other things, enhanced examination and reference to legal texts on the plan by each used provision.  

  • 29.
    Karlsson, Camia
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Utvecklingen av geografiska informationssystem: en studie vid Trollhättan stad och kommun2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 30.
    Keyvani, Ali
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Toward motion-capture-based digital human modelling2012Licentiate thesis, comprehensive summary (Other academic)
  • 31.
    Keyvani, Ali
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Johansson, Henrik
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Motion synthesizer platform for moving manikins2012In: 2012 AHFE International Conference 21-25 July 2012 Hilton San Francisco, Union Square, California: Conference proceedings, AHFE , 2012, p. 545-554Conference paper (Refereed)
  • 32.
    Keyvani, Ali
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Johansson, Henrik
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Lämkull, Dan
    Volvo Car Corporation.
    Örtengren, Roland
    Chalmers.
    Schema for Motion Capture Data Management2011In: Lecture Notes in Computer Science. 3rd International Conference on Digital Human Modeling, ICDHM 2011: Orlando, 9-14 July 2011, 2011, p. 99-108Conference paper (Refereed)
    Abstract [en]

    A unified database platform capable of storing both motion captured data and information about these motions (metadata) is described. The platform stores large motion captured data in order to be used by different applications for searching, comparing, analyzing and updating existing motions. The platform is intended to be used to choose a realistic motion in simulation of production lines. It is capable of supporting and handling different motion formats, various skeleton types and distinctive body regions in a uniform data model. Extended annotating system is also introduced to mark the captured data not only in the time domain (temporal) but also on different body regions (spatial). To utilize the platform, sample tests are performed to prove the functionality. Several motion captured data is uploaded to the database while MATLAB is used to access the data, ergonomically analyze the motions based on OWAS standard, and add the results to the database by automatic tagging of the postures.

  • 33.
    Keyvani, Ali
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering. University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Lämkull, Dan
    Volvo Car Corporation, Gothenburg.
    Bolmsjö, Gunnar
    University West, Department of Engineering Science, Division of Production Engineering.
    Örtengren, Roland
    Chalmers University.
    Using methods-time measurement to connect digital humans and motion databases2013In: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 8026, no Part 2, p. 343-352Article in journal (Refereed)
    Abstract [en]

    To simulate human motions in DHM tools, using techniques which are based on real human data is one promising solution. We have presented a solution in this study to connect motion databases with DHM tools. We have showed that using a motion database with MTM-based annotations is a promising way in order to synthesize natural looking motions. A platform consists of a Motion Database, a Motion Generator, and a DHM tool was introduced and tested. The results showed successful application of the presented platform in the designed test case. © 2013 Springer-Verlag.

  • 34.
    Lundström, Patrik
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Öinert, Johan
    Köpenhamns Universitet.
    Skew category algebras associated with partially defined dynamical systems2012In: International Journal of Mathematics, ISSN 0129-167X, Vol. 23, no 4, p. 16-Article in journal (Refereed)
    Abstract [en]

    We introduce partially defined dynamical systems defined on a topological space. To each such system we associate a functor s from a category G to Top^op and show that it defines what we call a skew category algebra AxG. We study the connection between topological freeness of s and, on the one hand, ideal properties of AxG and, on the other hand, maximal commutativity of A in AxG. In particular, we show that if G is a groupoid and for each e in ob(G) the group of all morphisms from e to e is countable and the topological space s(e) is Tychonoff and Baire, then the following assertions are equivalent: (i) s is topologically free; (ii) A has the ideal intersection property, that is if I is a nonzero ideal of AxG, then I \cap A is not equal to zero; (iii) the ring A is a maximal abelian complex subalgebra of AxG. Thereby, we generalize a result by Svensson, Silvestrov and de Jeu from the additive group of integers to a large class of groupoids.

  • 35.
    Löfstrand, Mynta
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    En studie om GIS-dokumentation iTrollhättan Energi AB - Affärsområde Vatten: Införande, behov och utveckling2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     The intention of this thesis is to provide an overview on how to introduce GIS in an organization and how documentation needs and the development prospect looks at Trollhättan Energy Water Management.

    The gathering of facts was made by interviews and literature studies. Due to own experience and knowledge in the Water Management GIS-documentation the search and gathering of facts was eased.

    The result indicates that there is a relatively large need to have documentation around the Water Management-organization in GIS. Many of the approached replied that they appreciate a common documentation for the cooperation and that it helps accessibility of information. The study also elucidate that the GIS-competence have to increase amongst the co-workers. And it also shows a lack of proper organization for the GIS-questions and that the GIS-question misses clear purpose and goal.

    The conclusion is that there is a need to establish a GIS strategy as a steering document and action plans along the GIS strategy. The GIS strategy shall discuss intention, goal and the questions around organization, capacity building and data policy among the incorporation of GIS. An action plan is a substantially plan of what has to be done and to control the work with GIS and information management of a short term.  

  • 36.
    Major, Stina
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Förtroendet för fastighetsmäklare2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    De senaste tio åren har undersökningar genomförts av bland annat Mäklarsamfundet (Wörmann, 2006) och Fastighetsbyrån (Fastighetsbyrån, 2010) där svenska folkets förtroende för mäklare granskats. I Fastighetsbyråns undersökning från december 2010 framkommer det att endast fem procent av svenskarna har högt förtroende för mäklare i allmänhet. Samtidigt presenterar flera stora kedjor att de har mer än 70 procent nöjda kunder, vilket kan verka något motsägelsefullt.

    Detta arbete syftar till att undersöka vad skillnaderna i dessa siffror beror på och vad som påverkar kundnöjdheten hos mäklares kunder. Detta görs genom intervjuer med personer som har olika förhållanden till mäklare för att se om åsikterna hos grupperna skiljer sig åt. Fem mäklarfirmor har dessutom ombetts delta för att ge en klarare bild av hur de mäter sin kundnöjdhet.

    De personer som deltagit i studien har angett att de inte baserar sina åsikter och synpunkter angående mäklare på en stereotyp, utan på egna erfarenheter. Ingen av de tillfrågade uppger att media har spelat in och påverkat deras bild av fastighetsmäklare. Istället är det enskilda mäklare som presterat eller underpresterat i förhållande till köpare och säljares förväntningar som bidragit till den bild de har av fastighetsmäklare.

    Information, öppenhet och ärlighet är de gemensamma nämnare som både köpare och säljare efterlyser hos en bra mäklare. Det är inga stora förändringar som behövs för att skapa ett bättre rykte och öka förtroendet för mäklarkåren.

  • 37. Norin, Dab
    et al.
    Johansson, Jan M.
    Mårtensson, Stig-Göran
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Geodetic activities in Sweden 2010–20142015Report (Other (popular science, discussion, etc.))
  • 38.
    Nozari, Masoud
    et al.
    Department of Geodesy, K.N. Toosi University of Technology, Tehran, Iran.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    An alternative approach to Eulerian pole determination and unification of velocity fields of tectonic motions2014In: Tectonophysics, ISSN 0040-1951, E-ISSN 1879-3266, Vol. 617, p. 79-87Article in journal (Refereed)
    Abstract [en]

    One of the methods of unifying the global positioning system (GPS) velocity fields (VFs) of tectonic motions is based on the Eulerian vector (EV) estimation. In this method the difference between each available local VF and a reference VF (REF) is derived and an EV is estimated for the differences in a least-squares sense. After that each local VF is unified with respect to REF using the EV. The classical approach to the EV determination is nonlinear and requires the approximate EV. To solve this problem a simple linear approach is developed in this paper for estimating the EV and applied for unifying the existing local VFs in Iran. Our approach is free of the approximate parameters of the EV, faster and more efficient than the classical one. Here, both of the classical and the new approaches are numerically applied and compared to each other; and used to unify the VFs covering a large part of Iran. The unified velocity field shows an overall northward motion with respect to Eurasia with a convergence pattern around the southern Caspian Basin and a little divergence in the central and southern areas.

  • 39.
    Nystedt, Patrik
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    A combinatorial proof of associativity of Ore extensions2013In: Discrete Mathematics, ISSN 0012-365X, E-ISSN 1872-681X, Vol. 313, no 23, p. 2748-2750Article in journal (Refereed)
    Abstract [en]

    We use a counting argument to show that Ore extensions are associative. 

  • 40.
    Nystedt, Patrik
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Öinert, J.
    Lund University, Centre for Mathematical Sciences.
    Simple rings and degree maps2014In: Journal of Algebra, ISSN 0021-8693, E-ISSN 1090-266X, Vol. 401, p. 201-219Article in journal (Refereed)
    Abstract [en]

    For an extension A/B of neither necessarily associative nor necessarily unital rings, we investigate the connection between simplicity of A with a property that we call A-simplicity of B. By this we mean that there is no non-trivial ideal I of B being A-invariant, that is satisfying A I ⊆ I A. We show that A-simplicity of B is a necessary condition for simplicity of A for a large class of ring extensions when B is a direct summand of A. To obtain sufficient conditions for simplicity of A, we introduce the concept of a degree map for A/B. By this we mean a map d from A to the set of non-negative integers satisfying the following two conditions: (d1) if a ∈ A, then d(a) = 0 if and only if a = 0; (d2) there is a subset X of B generating B as a ring such that for each non-zero ideal I of A and each non-zero a ∈ I there is a non-zero a ' ∈ I with d(a ') ≤ d(a) and d(a 'b - ba ') < d(a) for all b ∈ X. We show that if the centralizer C of B in A is an A-simple ring, every intersection of C with an ideal of A is A-invariant, A C A = A and there is a degree map for A/B, then A is simple. We apply these results to various types of graded and filtered rings, such as skew group rings, Ore extensions and Cayley-Dickson doublings. © 2013 Elsevier Inc.

  • 41.
    Nystedt, Patrik
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Öinert, Johan
    University of Copenhagen, Department of Mathematical Sciences.
    Simple skew category algebras associated with minimal partially defined dynamical systems2013In: Discrete and Continuous Dynamical Systems, ISSN 1078-0947, E-ISSN 1553-5231, Vol. 33, no 9, p. 4157-4171Article in journal (Refereed)
    Abstract [en]

    In this article, we continue our study of category dynamical systems, that is functors s from a category G to Topop, and their corresponding skew category algebras. Suppose that the spaces s(e), for e ∈ ob(G), are compact Hausdorff. We show that if (i) the skew category algebra is simple, then (ii) G is inverse connected, (iii) s is minimal and (iv) s is faithful. We also show that if G is a locally abelian groupoid, then (i) is equivalent to (ii), (iii) and (iv). Thereby, we generalize results by Öinert for skew group algebras to a large class of skew category algebras.

  • 42.
    Pettersson, Mattias
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ombyggnation och modernisering av transformatorstation för anslutning av vindkraft2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor´s thesis is carried out on behalf of Rejlers Ingenjörer in Gothenburg. The work aims to overall present the realization of two station design proposals, including components, functions, financial aspects and plans, in connection with a reconstruction and expansion of a substation. The substation currently has two voltage levels of 40 kV and 10 kV. In connection with the reconstruction, the station is supplemented by a further voltage level of 20 kV, for connection of a number of wind turbines. For the installation to meet basic requirements, the work is performed by sorting and putting together relevant information from applicable regulations, standards and technical guidelines. Further information is obtained through additional information from literature, catalogues, product sheets and verbal contact with the job requestor. In the thesis the two station design proposals are presented in compliance with the aim. The high voltage equipment is dimensioned and presented, and the relay protection functions are identified. In both options, the transformers are located outdoors with a station building that houses 10 kV, 20 kV switchgear, a battery room and a control room. The main difference between the alternatives is that one of the options has an outdoor air insulated 40 kV switchgear, while the second one has a more compact indoor air insulated switchgear. The total estimated cost, including operation and maintenance costs, over a 25-year period is estimated at 22.7 million Swedish kronor for the outdoor option and 22.4 million Swedish kronor for the indoor alternative. The difference in costs is expected to rise to the advantage of the indoor option if social costs during a power failure also are taken into account in the calculation. It is recommended that the substation be built according to the indoor option, since this is considered to provide the best overall economy, safety of operation and protection against unauthorized access.

  • 43.
    Prick, Mattias
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Blidberg, Christian
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Kulturhistorisk intressant bebyggelse: Bevarande med stöd av Plan- och Bygglagen2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Local authorities have the opportunity to protect preservative settlement in detailed development plans through to notify the protection on the properties that are worth preserving. What is allowed to protect with such provisions regulated in Chapter 4, Section 16§ PBL. Previous investigation shows that there may be problems with the formulation of these measures. Both to the lack of support in PBL and that they are ill-defined. In our study we will investigate how preservative provisions are designed in the municipalities of Vastra Gotaland County, if they have any shortage/lack of clarity. The material which has been examined is the detailed development plans under ongoing work in the municipalities in the meantime v. 14 to V. 16. To administrators of building permits in all of the municipalities of Vastra Gotaland County has a questionnaire sent out, which they have received respond to how it is to work with preservative settlement when they make their judgment on building permits. A review, which was based on the replies from the survey was made, which provides, inter alia, to their view on the importance of correct rules is given. The result of the survey shows that the greatest challenge for the building permit administrators is to convince property owners that they have a valuable building that is worthy of preservation. Clearer measures would facilitate this line of reasoning in contact with the property owner and give clear guidelines for the decision. The investigation shows that more than one-tenth of the provisions do not have legal aid or regulated under other legislation. The need of precision which PBL makes of the provisions in the detailed development plans are not satisfied in approximately half of the cases. This means that more than 60% of the provisions show shortage/lack of clarity.               

     

     

  • 44.
    Roos, Johan
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Framtagning av handbok för projektering och installation av värmekabel inom processindustrin2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the process industry heat tracing cables are diligently used to prevent liquids from freezing and to control their viscosity. Depending on which of these features that are sought, various methods and types of heating cable is used where both design and installation differs between them. Since there is no single source from where all the necessary information can be found it's difficult for the designer to get a tangible view of the process. The various sources can be both current standards in the field and the involved companies (suppliers and customers). In order to better prepare the designer and increase understanding of the subject to avoid common "pitfalls" along the way something is therefore needed that in a simple way both explains the basic principles and specific problems that often arise. This thesis addresses this problem by creating a handbook on the subject of heat tracing cables. The handbook is meant to be used both by novice and experienced designers. The theory of heat tracing cables have been collected by studying existing material from various suppliers and through interviews of contacts on Pentair Thermal Management and COWI AB. A similar interview was made with Preemraff in Lysekil to obtain a better understanding of how heat tracing cables are handled in a process industry. The basis for manual drafting has been derived from books concerning the subject instruction development and supplying technical information. The results of the theses conclude with a handbook for both novice and experienced designers. A suggestion for future research is to make a broader comparison by interviewing more companies, both suppliers and users, and thus be able to increase the usability of the handbook.

  • 45.
    Skoglund, Anneli
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Gustavsson, Malin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Detaljplanering: planbestämmelsers användning i praktiken2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 46.
    Tano, Ingrid
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Contributions to multivariate process capability indices2012Licentiate thesis, comprehensive summary (Other academic)
  • 47.
    Tano, Ingrid
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Vännman, Kerstin
    Luleå Tekniska universitet.
    A multivariate process capability index based on the first principal component only2013In: Quality and Reliability Engineering International, ISSN 0748-8017, E-ISSN 1099-1638, Vol. 29, no 7, p. 987-1003Article in journal (Refereed)
  • 48.
    Tenzer, Robert
    et al.
    Wuhan University, Sch Geodesy & Geomat, Key Lab Geospace Environm & Geodesy, Wuhan 430072, Peoples R China.
    Eshagh, Mehdi
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Global Sub-Crustal Stress Field2016In: Geostatistical and Geospatial Approaches for the Characterization of Natural Resources in the Environment / [ed] Raju, N. Janardhana, Springer International Publishing , 2016, p. 461-465Chapter in book (Other academic)
    Abstract [en]

    The sub-crustal stress has been traditionally computed using the Runcorn's formulae. This method allows computing the stress field only with a very limited spectral resolution. To overcome this problem, we apply a new method of computing the sub-crustal stress components based on utilizing the stress function with a subsequent numerical differentiation. This method increases the (degree-dependent) convergence domain of the asymptotically-convergent series and consequently allows evaluating the stress components to a higher spectral resolution compatible with currently available global crustal models. This method also facilitates the variable Moho geometry, instead of assuming only a constant Moho depth in the Runcorn's formulae. The crustal thickness and the sub-crustal stress are then determined directly from gravity and (seismic) crustal structure models. The numerical result reveals that the largest intensity of the sub-crustal stress occurs mainly along seismically active convergent tectonic plate boundaries, particularly along oceanic subduction zones and continent-to-continent collision zones.

  • 49.
    Thorstensson, Andreas
    et al.
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Ödman, John
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Huvudmannaskap för allmän plats: en studie av ansvarsfördelning med fokus på delat huvudmannaskap2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 50.
    Vanhatalo, E.
    et al.
    Luleå University of Technology, Quality Technology and Management.
    Bergquist, B.
    Luleå University of Technology, Quality Technology and Management.
    Vännman, Kerstin
    University West, Department of Engineering Science, Division of Natural Sciences and Electrical and Surveying Engineering.
    Towards improved analysis methods for two-level factorial experiments with time series responses2013In: Quality and Reliability Engineering International, ISSN 0748-8017, E-ISSN 1099-1638, Vol. 29, no 5, p. 725-741Article in journal (Refereed)
    Abstract [en]

    Dynamic processes exhibit a time delay between the disturbances and the resulting process response. Therefore, one has to acknowledge process dynamics, such as transition times, when planning and analyzing experiments in dynamic processes. In this article, we explore, discuss, and compare different methods to estimate location effects for two-level factorial experiments where the responses are represented by time series. Particularly, we outline the use of intervention-noise modeling to estimate the effects and to compare this method by using the averages of the response observations in each run as the single response. The comparisons are made by simulated experiments using a dynamic continuous process model. The results show that the effect estimates for the different analysis methods are similar. Using the average of the response in each run, but removing the transition time, is found to be a competitive, robust, and straightforward method, whereas intervention-noise models are found to be more comprehensive, render slightly fewer spurious effects, find more of the active effects for unreplicated experiments and provide the possibility to model effect dynamics. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.

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