Change search
Refine search result
10111213 601 - 623 of 623
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 601.
    Kop, Jure
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Tests of New Solutions to the Direct and Indirect Geodetic problems on the Ellipsoid2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main objective of this thesis is to test new methods on solving the direct and indirectgeodetic problems on the ellipsoid as proposed in the article by Prof. Sjöberg, published in theJournal of Geodesy in 2006. Methods used for direct and indirect geodetic problems takeadvantage of numerical integration. First, strict solution for the sphere is considered then asmall correction to the ellipsoid determined by numerical integration is added to obtain the finalsolution. The author also deals with the equations on how to compute the area limited by theequator, two meridians and the geodesic between two points using numerical integration aswell.Furthermore the geodetic intersection on the ellipsoid is also considered as described by thesame author in a different article. The solution for the latitude is obtained for the sphere plus asmall correction using numerical integration. As this is iterative procedure, once obtained, thelongitude is calculated without iteration.With the increase of processor power in computers during the last decade or two the logicalconclusion is to use computers in proving mathematical equations. The numerical integrationhas not yet been used in geodesy in this manner, therefore it is used here.Findings of our tests conclude that numerical integration used for purposes above is good whenused in certain frames and that it has to be used with caution. In fact when numericalintegration is used in those frames it is quite safe to use the formulas as they prove veryaccurate.

  • 602.
    Gradin, Jesper
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Geodesy (closed 20110301).
    Aided inertial navigation field testsusing an RLG IMU2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis a system for aided inertial navigation (aided INS or AINS) has been testedthrough a number of kinematic experiments. In the experiments, data was collected andpost-processed by different methods. The system was built up by an IMU (inertial measurementunit) aided by a GPS receiver and an odometer. To fuse and filter the sensor dataa Kalman filter from the AINS Matlab Toolbox has been used.The following equipment was used• iNAV-RQH; IMU from iMAR• System 4000SSE; GPS receiver from Trimble• Correvit L-CE; odometer from Corsys-DatronThe following methods (and combinations of these) were used on the acquired data• INS with Zero velocity updates (ZUPT)• INS under non holonomic constraints• INS integrated with GPS• INS integrated with odometerThe work resulted in a number of trajectories; some of these could be compared with areference trajectory, in other cases this was not possible due to the nature of the experiment.Also there are no guidelines or standards on how to test a system in order to compare itwith other systems.Over all, good results were achieved with the system. The AINS toolbox worked outwell and it was indicated that the odometer could be used as an important aiding source inan aided inertial navigation system.

  • 603.
    Lahoz, Alicia E.porcar
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    An analysis of how geographicalfactors affect real estate prices2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the real estate business it is common to assume that the value and potential of a property isfundamentally determined by its location. Certain sites are attractive because they may have abeautiful view, shore and forests in the vicinity, good rail and road connections without noiseand all kind of public and private services. Corporate Property Evaluation has generallyfocused on financial methods that analyse how site-specific variables will influence potentialcosts and revenues from the site; unfortunately these methods sometimes do not take inaccount all the possible considerations for the site. This project studies the importance ofspatial factors in real estate appraisal and evaluates which of them affect the value of theproperties. The result could be useful to evaluate, for example, for geographical expansionstrategies. The study is carried out using Geographical Information Systems, which arecomputer systems capable of storing, displaying and analysing geographical information. Thisstudy is performed for the Stockholm’s municipality located in Sweden.In a Multi Criteria Evaluation the attempt is to combine a set of factors and criteria to comeup with a basis for a decision according to a particular objective. In this project the objectiveis to find out which factors cause a higher price in properties. We know which properties haveelevated price but we don’t know the factors that affect it. For this reason, the thought is toperform a MCE analysis approach a large number of times with different combinations ofdata, criteria and weights in order to search for a combination that gives a result that fits theknown prices. This method can be seen as a Data Mining approach. Data Mining is atechnique for distilling data and to find useful information.The results are based on the output obtained by the Data Mining technique and are displayedboth visually and in an Excel table. By visualising the results in maps it has been possible tocompare them with original data, finding out that factors like the proximity to water and thenumber of foreign people living in an area affect the value of the land. Several factors havebeen included in the analysis, being the most important the quality of the environment, thesocial standing of the population and the public transportation facilities. Although the resultsare quite reasonable, this analysis could be more accurate by testing more combinations ofdata and weights.

  • 604.
    Jiang, Jing
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics (closed 20110301).
    Analysis of the Suitable and Low-CostSites for Industrial LandUsing Multi Criteria Evaluation:A Case of Panzhihua, China2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the rapid industrial development, the Geographic Information System (GIS) and Multi CriteriaEvaluation (MCE) have been widely used to analysis the land utilization. In this project, the area ofPanzhihua was chosen to conduct the industrial suitability and economic land analysis. GIS analysis wasperformed to investigate the suitability and cost of land using various data such as DEM and various landuseinformation. The most important spatial analysis techniques used in this project are Multi Criteria Evaluationand a dual equation. Costs associated with terrain conditions (slope), green land, build up area, factories,streets, country road, highway, railway and water body were derived from virtual costs that are used toidentify the relative costs of all criteria. The suitability- cost ratio was performed incorporating with the landsuitability map and land cost map to identify the suitable-low cost industrial siting.

  • 605.
    Rosewarne, Stephen
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Deformation Study of the Vasa Ship2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main objective of this study is to detect deformation in the hull or moorings of therecovered and restored 17th century Swedish warship Vasaskeppet (The Vasa Ship)housed in a Stockholm museum. The ship was underwater for centuries and presentssome unique challenges to those working to maintain it. This study aims to determinewhether or not this priceless historical artefact has deformed in recent years and to helpcontribute to its maintenance. This deformation study includes an analysis conducted inthree stages: (i) to examine the stability and reliability of the underlying control networkin use at the museum; (ii) to examine the way in which the ship is moving with respect tothe museum structure; and (iii) to detect any deformation or movement evident inindividual parts of the ship with respect to one another. The analysis of the Vasa is anactive area of research and the primary motivation for this study is the fact the ship isunique in many respects, and anything that can be done must be done to ensure itspreservation.

  • 606.
    Haque, Md Ubydul
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Mapping malaria vector habitatsin the dry season in Bangladeshusing Spot imagery2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Malaria is a major disease burden in the southeast part (Rangamati, Khagracharia andBandarban) of Bangladesh. This study uses satellite based data obtained from SPOT-5 forinvestigating association between land cover patterns and malaria incidences in an area of thatpart of Bangladesh. Climatic conditions were also examined to determine its influence onmosquito breeding and malaria incidences. Unsupervised classification was performed usingground-truth data to classify the land cover patterns of the area; and NDVI of the area wascomputed. Overall accuracies of 89.9%, 87.9% and 89.5% were achieved in Kuhalong,Shuloka and Bandarban respectively. These data sets were used to predict risk for malariautilizing statistical tools of the SPSS software. Factor analysis was carried out to investigaterelationship between land cover patterns and malaria cases in the different subunits (calledunions) of the study area. Malaria cases were not evenly distributed among the unions. InKuhalong union, there were more malaria cases compared to the other unions, Shuloka andBandarban. Kuhalong is covered with more water bodies than that in the other two unions.The results of the analysis illustrate malaria cases are correlated with land cover like water,light forest, and agricultural land; and are also associated with average humidity and averageNDVI.

  • 607.
    Israelsson, Torgny
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Geodesy (closed 20110301).
    Shoumar, Youseff
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Geodesy (closed 20110301).
    Motion Detection with GPS2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Using GPS technology in motion detection and deformation measurements are getting more common. Different concepts are used; GPS as a stand-alone system or together with other surveying methods. A lot of research is done in this field and several types of applications have been developed. In this work only GPS receivers are used and the focus is on centimetre level motions over short periods of time. Because the created horizontal motion is known the accuracy of the by GPS detected motion can be computed for different settings and in different environments. A brief overview of the limitations and error sources in GPS surveying is also given.The motions are monitored with a commercial software, Motion Tracker, from Trimble and with On-the-Fly processed data files from Trimble Total Control that are run in a Matlab program in order to get RMS values for the detected motions and plots showing the created true motion and the by GPS measured motion. In addition the procedure to write a batch file in order to run GNNET-RTK, a software from GEO++, is investigated. This software package makes it possible to simultaneously do real-time processing of several reference and rover stations.When the conditions for GPS surveying are good, the quality of detected motions show promising results. Millimetre accuracy is achieved even if only GPS sensors are used and the epochs are as short as one minute. In built up areas with a lot of obstructions of the sky the error sources and limitations of GPS, e.g. multipath, has a significant impact on the results and longer observation times are needed. In such areas this work indicates that for demanding high accuracy applications GPS needs other types of sensors as complement, to be able to provide stable reliable solutions with millimetre accuracy.

  • 608.
    Djenaliev, Akjol
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics (closed 20110301).
    Multicriteria decision makingand GIS for railroad planningin Kyrgyzstan2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The location of rail station and route planning for new railways in a country constitutecomplicated planning processes which involve the consideration and analysis of various datasets. It includes the evaluation of socio-economic and technical parameters to minimizeenvironmental impacts of different alternatives and to achieve the development of alternativestation and corridors for the planned rail networks link. In Kyrgyzstan, these tasks areimplemented using traditional manual routines that the choice of a location rail station andselection of corridor for new railways are based on the topography of the land.The use of modern technological tools like Geographic Information System (GIS) forsuitable location of rail stations and selection of optimum routes involves managing a varietyof data sets from different sources and at different scales. This work is intended to investigateand show the capabilities of GIS in railroad planning and station location processes using partof the China-Kyrgyzstan-Uzbekistan railway in the south of Kyrgyzstan as a case study.The study will identify the information needs of different factors and evaluationcriteria for locating station and railroad planning. To achieve these objectives spatialmulticriteria decision making (MCDM) processes for planning the rail station and the routeswere designed and developed using GIS.The relative importance of the parameters in rail station location and rail routeselection has been determined in cooperation with rail experts. The obtained scores were usedin pairwise comparison to determine the weight of factors/criteria maps related to theseparameters. These weighted factors/criteria maps were overlaid and suitability maps werecreated in GIS for rail station location and rail route selection. The Weighted linearcombination (WLC) and The Analytical Hierarchy Process (AHP) were used to derive thesesuitability maps.

  • 609.
    Dastgir, Naeim
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Processing SAR data using RangeDoppler and Chirp Scaling Algorithms2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Applications of self-illuminating remote sensing systems, and among those, Radar Imagery is growingrapidly. Unique properties of Synthetic Aperture Radar (SAR) system makes it one of the most popularand applicable methods of self illuminating remote sensing techniques for ground deformationmonitoring, seismic studies, and many photogrammetry applications.There are several methods and algorithms for processing SAR data, each are convenient for differentpurposes. Two more common and reliable algorithms are developed in this thesis: a Range DopplerAlgorithm and a Chirp Scaling Algorithm.Available software packages and toolboxes for processing SAR data such as DORIS, ROI-PAC, RAT andPULSAR have their advantage and disadvantages. Most of these packages run on Linux platform, aredifficult to use, and require quite a few pre-processing data preparations. Besides there is no general SARprocessing application that can handle all data types or suitable for all purposes. There are also softwarepackages (such as ROI-PAC) with restrictions for people from certain countries.The objective of this thesis is to process SAR data using two more common algorithms, run a comparisonbetween results of these two algorithms and to process InSAR pair images to form an Interferogram andto create a DEM. A Matlab based program is developed for this purpose with graphical user interface anda few visualization enhancement features, which facilitates processing data and producing desired output.Then, I investigate the effect of different frequency domains in the resulting image.The program I created in my thesis, has several advantages: it is open-source and very easy to modify.The program is coded in MATLAB, therefore it does not need a vast programming knowledge to be ableto customize it. You can run it on any platform that can run MATLAB 7+.At the end of this thesis, I conclude that A Range Doppler Algorithm with secondary range compressionperformed in 2D-frequency domain has a result as good as a Chirp Scaling Algorithm and has lesscomputational complexity and consumes less time. No general SAR processing algorithm could beintroduced. Most of the times algorithms need to be adjusted for particular datasets, or particularapplications. Besides, the most complicated algorithm is not always the best algorithm. For example, for apoint target detection purpose, two filtering steps in range and azimuth direction provides accurateenough result.

  • 610.
    Hammar, Anna
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Geodesy (closed 20110301).
    Quality comparison of automatic3D city house modelling methodsfrom laser data2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today there are different methods to automatically generate 3D models from laser data, whichgive varying results. The two methods used in this study are, a fully automatic methoddeveloped by the Swedish Defence Research Agency, FOI, and a semiautomatic methodwithin the program Terra Scan which is developed by Terrasolid, a Finnish company.The report describes the way these methods have been implemented, and it evaluates theoutput quality of each model set created from specified criteria.In order to be able to verify the quality, a statistical model was created with the purpose ofusing it for other situations as well in the future.The modelling methods gave different results and both had their strengths and theirweaknesses, which makes them applicable for different tasks. The strength in FOI’s method isthat it could recreate even more advanced buildings and still get a good visual impression, e.g.Stockholm’s central station.One advantage with the method used in Terra Scan is that it has good capabilities and tools toedit the models, which makes it possible to vary the quality depending on the purpose.In order to generate the best result this method is not supposed to be used in an automaticway.

  • 611.
    Jayamangal, Raghavendra
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics (closed 20110301).
    Quantification of coastal erosion alongSpey Bay and the Spey River usingphotogrammetry and LiDARimagery-derived DTMs2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Coastal erosion has become an important phenomenon for all the beaches in theworld. There are many physical changes involved in the Coastal erosion. This paperis more concentrated towards the quantification of the coastal erosion andmovements of sediments along the beach. It tries to understand the volumetricchanges and Sediment movement along the Spey Mouth and River Spey. The thesisincludes the study of the changes along the beach and river over a long period oftime. The study area is located to the Northeastern part of the Scotland, UK. The areais located at Latitude 490N and Longitude 30W .The main purpose of this thesis work is to create the DTMs from the stereo imagesgot from the year 2000 using the software Socet Set 5.3. Then Orthophotos arecreated using the same software for further study of the Geomorphologic changesalong the Spey mouth and River Spey. The DTM and images derived from LiDAR inthe year 2003 are also used to study the changes. This research explains thephotogrammetrical methods used to generate the Orthophoto and DTM for theLower Spey River and Spey beach. Using the generated models in the GIS analysis tocalculate the volume and area change in the Spey area. This paper aims to visualizeand understand the changes in height that took place from 2000 to 2003.The main objectives of this project include the calculation of the changes in volumeof the Spey River and the Spey Bay Beach; generate the height changes in differentparts of the Spey area and to visualize the processes.

  • 612.
    Addai, Joseph
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Quantification of temporal changes in metal loads – Moss data over 20 years2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Environmental monitoring, assessment and conservation programmes worldwide have led to the development of scientific and technological methods to study the changes in our environment. As a result, a technique for monitoring atmospheric metal deposition was developed in Sweden in the 1960s. This technique is based on the principle that, carpet-forming moss obtains its nutrients from dry deposition particles in the air. The Swedish Environmental Research institute (IVL) has a database of concentrations of metals in terrestrial mosses. These were sampled during the national moss surveys (1975 – 2000). From these point data, long-term changes in the deposition loads can be studied.One aim of this project is to create continuous surfaces for these point data and to develop a technique to map the spatio-temporal changes. It also seeks to quantify the temporal changes in metal loads of the moss data for over 20 years. With the amount of data increasing from various air quality assessments and monitoring methods, it is prudent to approach the data analysis from a multidisciplinary perspective. By using statistics, geostatistic, GIS and visualization methods, the quantitative, spatial and temporal trends of the moss surveys were analysed. Multidimensional visualizations based on exploratory data analysis were applied to the data to visualize and reveal trends in the multivariate data.The project area comprised the whole Sweden with the data from 1975 to 2000, with the exception of the moss survey in 1975, which was conducted only in southern Sweden. A combination of GIS, geostatistics and high dimensional visualization techniques were applied in the data cleaning and analysis stages.The results of the project show the rate of change of metal loads over the years and the spatial distribution of the metal depositions as well. The visual approach used from the data cleaning to results presentation makes it easily comprehensible to non-scientist as well.

  • 613.
    Andrei, Octavian
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    3D affine coordinate transformations2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates the three-dimensional (3D) coordinate transformation from a globalgeocentric coordinate system to a national terrestrial coordinate system. Numerical studies arecarried out using the Swedish geodetic data SWEREF 93 and RT90/RH70. Based on theHelmert transformation model with 7-parameters, two new models have been studied: firstly ageneral 3D affine transformation model has been developed using 9-parameters (threetranslations, three rotations and three scale factors) and secondly the model with 8-parameters(three translations, three rotations and two scale factors) has been derived. To estimate the 3Dtransformation parameters from given coordinates in the two systems, the linearizedobservation equations were derived. Numerical tests were carried out using a local (North,East, Up) topocentric coordinate system derived from the given global geocentric system. Thetransformation parameters and the residuals of the coordinates of the common points werecomputed. The investigation shows the horizontal scale factor is significantly different by thevertical scale factor. The residuals of the control points were expressed in a separate (North,East, Up) coordinate system for each control point. Some investigations on the weightingprocess between horizontal and vertical components were also carried out, and an optimalweighting model was derived in order to reduce the residuals in horizontal componentswithout changing the coordinates.

  • 614.
    Kumar, Krishnasamy Satish
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    A Usability Engineeringfor UTÖ Tourism Information System2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Tourism Information System of UTÖ was developed in ARCGIS9.0 by KARToTEKTeknikutbildarna AB. This information system helps people who visit this island by providinginformation on various tourist spots, hotels, restaurants etc. This system has a menu drivenGUI (Graphical user interface) which includes a map of the island, various tools, menus andsubmenus that can be used to find information about different places in this island. Thissystem is taken care by the tourist office which can be used by tourists who want to get moreinformation about the island.Since many tourists visit this island every year it is necessary to modify UTÖ touristinformation system more user friendly. To improve UTÖ tourist information system varioususability tests were conducted with this system which was setup in a lab and test users weregiven some tasks to solve using this system. Test users were interviewed about how theysolved the tasks and also asked to give their own view to improve the system. As a touristwhat are additional features that are necessary in the system to improve the user friendliness.Currently UTÖ Tourism Information System is a standalone system which is not linked to anyweb based application. According to usability test conducted for UTÖ tourist informationsystem, the future system can be developed as follows: The system should be developed into aweb based application. So information can be accessed any where in the world.There should be some pictures in the popup information window screen and the menustructure of system has to be modified. North arrow symbol, over all view of image whichshows near by surrounding island should be added. Legend of the map should be added forbetter understanding of information conveyed by colors that are displayed in the map. Thedisplay structure of distance measurement tools needs to be changed. Proper symbols formany submenus need to be changed for better understanding of information conveyed by thesymbols.Main challenge of this usability test of TURGIS (is the name given to the GUI (Graphical userinterface) of the of UTÖ tourist information system) is this system should be modular andcapable to be used by wide range of people without any guidance of others. Usability testingis important for developing effective design of systems by which users can interacteffectively.

  • 615.
    Tao, Zhang
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics (closed 20110301).
    Application of GIS and CARE-W systemson water distribution networks inSkärholmen in Stockholm2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Urban infrastructure management is becoming more and more important for cities around theworld. This paper presents a management and rehabilitation strategy for water distributionnetworks, which is to ensure that they are economically under a healthy condition over anextended period of time. The idea is to pay more attention on pro- active approaches thatuse predictive analysis to achieve long- term economic efficiency.One target in this project is to integrate Geographic Information System technology andComputer Aided Rehabilitation of Water Networks (CARE-W), a new developed toolkit inEurope. This thesis also aims to study and evaluate water distribution condition by using datafrom Stockholm Water Company in Sweden. Moreover the reliability of CARE-W toolkit istested. It concluded the experience including theory review, data preparation, and integrateprocess and achievement presentation.The test area is called Skärholmen pressure zone, consisting 4060 water mains and about1580 failures, which were recorded from year 1988 to 2005. In the experiment, datapreparation and analysis processes occupied above 80% of the project time. Three CARE-Wtools have been tested. They are Performance Indicator tool, Reliability Model and FailureModel. The Performance Indicator Tool and Reliability Model were run successfully, but theFailure Model failed in this project. However another approach from only GIS analysis hasbeen carried to achieve failure forecasting.In the final part, why some portions are in poorer positions compared to others are discussedbased on reality and results from the experience. Results are presented in graphs, GIS mapsand tables. These are mainly for decision makers to know the current situation of their assetand where they should put more energy on and how to make long term planning.

  • 616.
    Danila, Uliana
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Corrective Surfacefor GPS-levelling in Moldova2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main objective of this thesis is the construction of a corrective surface in theMoldova area for further conversion of the geodetic heights into normal heights. For thispurpose a detailed analysis of the optimal combination of heterogeneous height data ispresented, with particular emphasis on (i) modeling systematic errors and datuminconsistencies, (ii) separation of random errors and estimation of variance componentsfor each height type, and (iii) practical considerations for modernizing vertical controlsystems. Although the theoretical relationship between geodetic, normal heights andheight anomalies is simple in nature, its practical implementation has proven to be quitechallenging due to numerous factors that cause discrepancies among the combined heightdata. In addition, variance component estimation is applied to the common adjustment ofthe heterogeneous heights. This leads to the connection between the proper modelling ofsystematic errors and datum inconsistencies with the estimated variance components.Ultimately, one of the main motivations for this work is the need to introduce moderntools and techniques, such as GPS/levelling, in establishing a vertical control. Therefore,part of this thesis is aimed at bringing to the forefront some of the key issues that affectthe achievable accuracy level of GPS/levelling. Overall, the analysis of the optimalcombination of the heterogeneous height data conducted herein provides valuable insightto be used for a variety of height related applications.

  • 617.
    Ahmed, Kazi Iashtiak
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    ENVISAT ASAR for Land Cover Mappingand Change Detection2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The principal objective of this research is to investigate the capability of multi-temporal,multi-incidence angle, dual polarization ENVISAT ASAR imagery for extractinglanduse/land cover information in the rural-urban fringe of the Greater Toronto Area (GTA)using different image processing techniques and classification algorithms. An attempt todetermine the temporal change of landuse is also made.The multi-temporal ASAR imagery was first orthorectified using NTDB DEM and satelliteorbital models. Different image processing techniques, such as, Adaptive Speckle Filtering,Texture measures, Principal Component Analysis (PCA) were applied to the ASAR images.Backscatter profiles were generated for selected land cove classes. K Nearest neighbor (kNN)classifier was used to extract eleven land cover classes. Artificial Neural Network (ANN) wasalso tested with some selected combinations of ASAR imagery. The classification schemewas adopted from USGS alnuse/land cover classification scheme. Average accuracy, overallaccuracy and Kappa coefficients were calculated for all classifications.The raw ASAR images gave very poor results in identifying landuse/land cover classes due tothe presence of immense speckle. Enhanced Frost (EF) filtering significantly improved theclassification accuracies. For texture measures, eleven date Mean images produced the bestresult among all single set processed data. Combined Mean and Standard Deviation,combinations of different texture measures, further improved the results. Standard deviationprovided vital auxiliary boundary information to the classification resulting in theimprovement. The best kNN was achieved with combined Mean and Standard Deviation withmulti-incidence angle, dual polarization eleven date ASAR images. ANN further improvedthe classification results of the textured images. As for comparison of classifiers, It was foundthat, with complex combinations (dual polarization, multi-incidence angle), ANN performssignificantly better than kNN. The overall accuracy was 9.6% higher than that of kNN. Theresults were more or less similar in filtered images.Post classification change detection is largely dependent on classification accuracy ofindividual images. Even though, the classification results were somewhat satisfactory, theclassified ASAR image still had a significant amount or omission and commission errors withsome classes. The classification errors contributed a significant amount of noise in changedetection. The change detection procedure, however, was able to identify the areas ofsignificant change, for example, major new roads, new low and high built up areas and golfcourses.In brief, ENVISAT ASAR data was found to have vast potential in extracting land coverinformation. Especially with its all weather capability, ASAR can be used together with highresolutionoptical images for temporal studies of landuse/land cover change due to urbansprawl.

  • 618.
    Tornberg, Johan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Felfortplantningsanalys i GIS-projektgenom Monte Carlo-simulering2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Geographical Information Systems (GIS) are used to handle, display, analyze and distributegeographical data. The science is quite new and a lot of basic research is still done, partiallysince the development of computer technology continuously open new possibilities. In thisreport a Multi-Criteria Evaluation (MCE), made by SWECO Position, of a gas pipelinelocation in Södermanland, SWEDEN, is taken one step further by investigating how certainerrors propagate through the analysis. The subject for investigation is the soil map made byGeological Survey of Sweden (SGU) and the method chosen is Monte Carlo-simulation(MCS). The whole gas pipeline analysis is in this study successfully automized and run 150times with error simulated data to yield 150 pipelines with somewhat different pipelinebuildings. Results are then both visually and statistically interpreted and conclusions aredrawn that the MCS method is a valuable continuation of the multi-criteria evaluation. Thediscussion part points out potential weaknesses as the pseudo random numbers and makerecommendations for future studies. Lastly the need for good quality data and computationalpower are emphasized

  • 619.
    Trehn, Erik
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    GPS Precise Point PositioningAn Investigation in Reachable Accuracy2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Accurate positioning is very important in many various applications. Today one of the mostused methods for this is DGPS, i.e. relative positioning. DGPS can be extended to aWADGPS (Wide Area DGPS) which consists of a network of reference stations which covera whole region, country or continent. This implies that you are dependent on other factors outof control of the user, and that a connection to the reference stations is needed.Precise point positioning, PPP, is an absolute positioning method where no reference stationsare involved. Ordinary single point positioning is based on broadcast ephemeris, and theaccuracy is on the 15m level. Per definition PPP is based on precise ephemeris, with muchhigher accuracy in the orbital parameters and in the satellite clock information. The resultshould therefore be more accurate. Precise ephemeris are available in different levels ofaccuracies (final, rapid and ultra-rapid) and can be downloaded from the internet for free.Precise clock files are not available as ultra-rapid and therefore it is not possible to getaccurate PPP-solutions in real-time.In Sweden there are several networks for relative positioning, e.g. through SWEPOS orEPOS. This might not be the case in other areas. As accurate PPP-solutions are not availablein real-time, PPP could be used to establish a reference station for DGPS/RTK for real-timemeasurements in those areasThe objective of this research is to evaluate precise point positioning regarding accuracy.Observation files from both IGS and SWEPOS-stations have been used in order to find out ifyou can expect the same accuracy wherever you are on earth. A couple of points have alsobeen measured only for this investigation in order to find out if the result will be the sameunder ordinary conditions. Coordinates of each point are determined with different duration ofobservation times and different level of accuracy of the ephemeris (final, rapid and ultrarapid).Bernese 5.0 and Auto-Gipsy have been used to compute the PPP-solutions and thenthe result is compared with the true position. The self-measured points are also determinedwith a WADGPS (Omnistar) in order to easily be able to compare PPP with a traditionalmethod.As expected the result becomes better for longer observation times and with higher accuracyof the ephemeris. The difference in accuracy between using rapid and final ephemeris is sosmall that it can be neglected in most applications. In almost all cases the accuracy is betterthan 10cm after only one hour of observations with rapid ephemeris. The investigation doesnot indicate significantly differences in accuracy depending on latitude and differencesbetween the self-measured points and IGS- and SWEPOS-stations can also be neglected.Using rapid or final ephemeris, the PPP-derived coordinates are much more accurate than theones obtained with Omnistar.

  • 620.
    Luna, Maria Irene Rangel
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    High Resolution Satellite Data for MappingLanduse/Land-cover in the Rural-Urban Fringeof the Greater Toronto Area2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Landuse and land-cover classification from high resolution imagery has been seen as challenging by theremote sensing society. The high variability from pixel to pixel makes the use of pixel-based classifiersobsolete. Object-based classifiers along with rule-based descriptors can be used to overcome theseproblems because they consider the spatial distribution and topological relationships of the pixels. Theidentification of the landuse/land-cover classes based on objects and their spatial relationships can lead toa better classification results. The combination through fusion techniques of images with differentresolutions can also be used to improve landuse/land-cover classification.The objective of this research is to evaluate pixel- and object-based approaches for landuse/land-coverclassification and to identify which approach gives better results for high resolution imagery.QuickBird imagery covering the town of Richmond Hill, in the Greater Toronto Area (GTA), Ontario,Canada were used for landuse/land-cover classification. The classes considered were: water, low-densityresidential, transportation, contruction site, forest, golf course, corn, wheat, fallow, rapeseeds, pasture,parks, new low-density residential, commercial and industrial. The fusion techniques were used to mergePan and MS images were performed as an initial step: RGB-HIS using PCI Geomatica and wavelettransform with IHS using Matlab and Erdas Imagery. Pixel-based classifiers, such as MLC and Contextualwere compared to the object- and rule-based approach implemented in eCognition. It was found that thebest pixel-based classification results were obtained from MLC using 1-4 channels (kappa coefficient0.80662 and overall accuracy 83.71%). However, the classification from Wavelet-IHS Transformationfusion result implemented in Matlab with MLC (kappa coefficient 0.77637 and overall accuracy 81.10%)showed a balance between low loss of spectral information and the improved classification for objects notclearly defined in the original MS imagery.For the object-based and rule-based approach, it was found that a segmentation of 4 levels with theidentification of major land-cover types in the smallest scale and the integration of rules for theidentification of landuse classes in the other levels led to the best classification result for high-resolutionimagery (kappa coefficient 0.8565, and overall accuracy 86.70%). However, rules that describe classessuch as ‘parks’, ‘commercial’ and ‘industrial’ sites have to be improved in order to increase theidentification of these areas

  • 621.
    Lewen, Ingemar
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Use of gyrotheodolitein underground control network2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete omfattar en studie av gyroskop och gyroteodolit,byggnät i tunnlar samt en närmare studie av geodetiska referensnät ochmätmetoder i projekt Hallandsås.Projekt Hallandsås är ett järnvägsprojekt genom Hallandsås i södra Sverigedär två, 9 km långa parallella tunnlar ska byggas. Den nya järnvägen genomtunnlarna kommer att jämna ut en nuvarande svår järnvägssträckning av denvästra stambanan över åsen. Tunneln kommer att byggas med hjälp av enTunnelborrningsmaskin (TBM).Noggrannhetskraven för geodetiska referensnät i tunnlar är högt satta och iprojekt där TBM används är den ännu högre. Det totala genomslagsfelet iProjekt Hallandsås får ej överstiga ± 100 mm. Endast hälften av detta fåranvändas för osäkerhet i byggnät, dvs ± 50 mm. Möjligheten till att göranoggranna mätningar och etablera referensnät med hög noggrannhet ärbegränsade i tunnlarna. I normalfallet, när konstruktioner skall uppföras påmarkytan etableras först ett specifikt geodetiskt byggplatsnät. Detta nätansluts mot nationella stomnät eller andra regionala stomnät som omsluterbyggplatsen. När en tunnel skall byggas är det också möjligt att konstruera ettövergripande stomnät för tunnelprojektet. Det är när dessa nät skall förtätas tillbygg- och bruksnät som skillnaderna börjar. När byggnation sker på markytanär det möjligt att även ansluta och utjämna dessa underliggande nät motöverordnade punkter som omsluter underliggande nät och därefter kanbyggande påbörjas. Denna sista procedur är ej möjlig när en tunnel skallbyggas.Det finns dock metoder för att optimera byggnät i tunnel. Detta examensarbetekommer att titta närmare på några av dessa metoder, framförallt hur olikanätkonfigurationer påverkar noggrannheten för genomslag samt möjlighetenatt kontrollera näten genom överbestämmande mätningar. Gyroinstrumentet,korrekt använt är en av de viktigaste metoderna för att både kontrollera ochförbättra noggrannheten i ett byggnät i tunnel.Studierna i detta examensarbete kommer att påvisa att genomslagsfelet i ettflygande polygontåg förbättras avsevärt av gyromätningar, även ett meröverbestämt nät förbättras, dock inte lika mycket. Vi kommer också att se attgyromätningar spelar en avgörande roll för kontrollerbarheten hos ett flygandepolygontåg även om ett mer överbestämt nät alltid kommer att vara bättre närdet gäller att söka efter och eliminera fel.Detta examensarbete behandlar endast mätningar i plana koordinatsystem.

  • 622.
    Lewén, Ingemar
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Use of gyrotheodolitein underground control network2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis comprises a study of the gyroscope and the gyrotheodolite, tunnel control networks and a case study of geodetic reference networks and survey methods in the Project Hallandsås. The Project Hallandsås is a railroad tunnel project through the ridge of Hallandsås in the south of Sweden. Two parallel, 9 kilometres long, tunnels are to be constructed. The railway through these tunnels will smooth a difficult section of the Swedish main western railroad. The tunnel is excavated and lined with enforced concrete using a Tunnel Boring Machine (TBM).The demands of accuracy of geodetic reference networks in a tunnel projectare high and in projects using TBM:s, even higher. The total breakthrough accuracy in Project Hallandsås is ± 100 mm. Of this the surveys may use half of this tolerance, i.e. ± 50 mm. The possibility to do accurate surveys and establish accurate reference network are limited. In the normal case when construction takes place on the surface, the first thing that is done is to establish a site-specific geodetic network. The networks are connected to national networks or other regional networks surrounding the construction site.To have a superordinate site-specific geodetic network is also possible for a tunnel project. The differences begin with the establishment of working/construction networks below the superordinate network through densification of higher project networks. In the surface construction case it ispossible to connect the surveys to points that surround the construction area and once the networks are adjusted and checked for errors toward all points, construction may begin. This last procedure is not possible when a tunnel is excavated.However, there are methods to optimise the tunnel control network. This thesis will look at some of these methods, particularly on how different configurations of network affect the breakthrough accuracy and possibility to check the networks through redundant surveys. The gyro instrument, correctly used, is one of the most important methods to both check and improve the accuracy of the tunnel control network.The studies in this thesis will show that the breakthrough error of an open end traverse is much improved by using gyro observations, and that a more redundant network is also improved but to a lower degree. We will also seethat the gyro observations plays a significant role in checking the open-ended traverse for errors even though more redundant network will always be betterfor the checking and elimination of errors. This thesis will only discuss surveys in the plane coordinate system.

  • 623.
    Muyingo, Henry
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Are listed property companies in Sweden ready for fair value accounting?  2002Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this Masters thesis has been to find out if, and how, listed Swedish property companies have prepared themselves for the regulation passed by the European Parliament that requires all EU companies listed in a regulated market as well as companies preparing admission to trading, at the latest from 2005 onwards, to prepare their consolidated financial statements in accordance with a single set of accounting standards, International Accounting Standards (IAS). The thesis work has been concentrated on the analysis of the fair value model in IAS 40, investment property and how companies will measure the fair value of their property.

    The data and results for this study were collected through interviewing various actors in the real estate market in Sweden, the UK and the Netherlands on the use of fair value accounting for investment properties.

    Results from the study show that:

    • 57% of the listed Swedish property companies have started preparations to apply IAS by the year 2005 but it is not likely that any of the companies will change before 2005.

    • Currently there is significant divergence between some of the IAS and the RRs, which is causing some problems in the conversion process. However there is a general misconception that Swedish laws will need to be revised before the EU regulation can come into effect.

    • Changes in accounting principles will not affect the underlying cash flows and financial analysts will probably not take much notice of the new " IAS profits".

    • Unlike in the UK and the Netherlands, use of the fair value model will not affect the dividend payouts or remuneration policies in Sweden. But it will affect the accounting for long leasehold property investments in all of the three countries.

    • The fair value model was considered to have a lot of advantages over the cost model.

    • Listed Swedish property companies, unlike the English and Dutch companies, are not ready to adopt the use of the fair value model mainly due to the uncertainty surrounding the measurement of the fair values.

    • Measurement of the fair values will be based mainly on the discounted cash flow method.

    • In contrast to the companies studied in the UK and the Netherlands, Swedish property managers were distrustful of the exclusive use of external valuers.

10111213 601 - 623 of 623
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf