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  • 1351.
    Zhao, Ming
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics. University of Gävle, Center for Logistics and Innovative Production.
    Proceedings of 2011 9th International Conference on Reliability, Maintainability and Safety2011Conference proceedings (editor) (Refereed)
  • 1352.
    Zhao, Ming
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics. University of Gävle, Center for Logistics and Innovative Production. Reliability Engineering Center, Guizhou University, Guiyang, China .
    Yang, Jianfeng
    Guizho University.
    A DCA-based method for software prognostics and health management2012In: Proceedings of IEEE 2012 Prognostics and System Health Management Conference, PHM-2012, 2012, p. 6228830-Conference paper (Refereed)
    Abstract [en]

    In recent years, the prognostics and health management (PHM) technique has greatly been developed especially for electronic devices and systems. Little work, however, has been done on PHM techniques for software systems. During their total lifecycle, the software systems, due to various reasons such as new requirements or changes in technology, have to experience changes that can lead to a degeneration of the system's architecture. Therefore, it is important and necessary to identify and predict the software health status in order to avoid serious degeneration or erosion of system's architecture. In this paper, a software PHM approach based on Discriminant Coordinates Analysis (DCA) is proposed, and the health status of software systems is suggested to be categorized into five groups: Healthy, Normal, Sub-healthy, Unhealthy and Deteriorated. The proposed model based on software design metrics can help managers and developers predict and identify the software health status. Numerical example based on simulation data is given to illustrate its application on the modeling process.

  • 1353.
    Zhao, Ming
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics. University of Gävle, Center for Logistics and Innovative Production.
    Zhang, Y. J.
    School of Mathematics and Physics, Anhui University of Technology, Maanshan, China.
    Yang, J. F.
    Faculty of Information Engineering, Guizhou Institute of Technology, Guiyang, China.
    Masked data analysis for storage reliability model with initial failures2018In: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018 / [ed] Stein Haugen, Anne Barros, Coen van Gulijk, Trond Kongsvik, Jan Erik Vinnem, CRC Press/Balkema , 2018, p. 2565-2572Conference paper (Refereed)
    Abstract [en]

    Storage reliability is of importance for the products that largely stay in storage in their total life-cycle such as warning systems for harmful radiation detection, rescue systems, many kinds of defense systems, etc. The storage reliability of a product is commonly defined as the probability that the product can perform its specific function for a period of specific storage time under specific storage environment. Logically, the failures of the product in storage should be identified with the same criteria as in its operation process. However, the failure data in storage may be observed indirectly through the maintenance or inspection activities. Nevertheless, when the storage reliability is concerned in general, the reliability model should take into consideration the possibility that the operational reliability does not start at 100%, for example, the one-shot product may have only 96% operational reliability when they are newly produced. In this paper, the storage reliability model with possibly initial failures, which are usually neglected at the beginning of storage in most of storage models, is studied on the statistical analysis method when the masked data are observed. The parametric estimation procedure, based on the Least Squares method, is developed generally by applying an EM-like (Expectation and Maximization) algorithm for the storage data in which some information about which components have caused the system failures is not known, namely the failure data are masked. The estimates of the model parameters including the initial reliability are formalized. In the case of exponentially distributed storage lifetime and series system, a numerical example is provided to illustrate the method and procedure though the method is not limited to such case. The results should be useful for planning a storage environment, decision-making concerning the maximum length of storage, maintenance strategy optimization and identifying the production quality.

  • 1354.
    Zhao, Ming
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics. University of Gävle, Center for Logistics and Innovative Production.
    Zhang, Y
    Guizho University.
    Xu, F R
    Guizho University.
    ESS profiles with step stress level2011In: ICRMS'2011 - Safety First, Reliability Primary: Proceedings of 2011 9th International Conference on Reliability, Maintainability and Safety, 2011, p. 1156-1161Conference paper (Refereed)
    Abstract [en]

    Environmental Stress Screening (ESS) is usually referred to the process of exposing a product to environmental stresses for detecting and eliminating latent defects made in manufacturing process. The common ESS profiles are using thermal cycling, random vibration or their combinations as the screening stresses. Various guidelines and standards have been available for determining an ESS profile. Nevertheless, there are cases that the standard ESS profiles may not be efficient enough to detect the latent defects in some manufacturing process. This paper reports the results of one industrial project on the ESS profile design for circuits. In the project, a comparative study was carried out for the evaluation of the ESS strength under the ESS profiles with incremental step stresses (ISS). The ISS profile under the study is firstly to implement a step thermal cycling and then perform the test with two screening stimuli concurrently: ordinary thermal cycling and random vibration of step increasing intensity levels. For the purpose of the comparative study, the ESS test samples were consisted of two groups A and B that were made at two different levels of manufacturing: soldering by skilled and unskilled workers, respectively. The comparative study shows that the ISS profiles are effective for exposing the latent defects in sample group A and B. Based on the project results, an ESS profile is recommended in this paper.

  • 1355.
    ZHAO, YANG
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    WU, LEI
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Driving Force and Challenge of Developing Low-Carbon Economy in China2010Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    With the growth of population and development of the global economy, the unrestrained use of natural and energy resources have seriously influenced environment and economy of world. Many people start to realize the serious environmental problems that come from the high energy utilizations, especially of high carbon dioxide (CO2) emissions. So Low-Carbon Economy has become focus of attention around the world; it also has become every country‟s strategic goals for future development under this global situation.As the biggest country of CO2 emissions in the world, China‟s development of Low-Carbon Economy is increasingly influencing the economy and environmental development in the world, and the country has faced more and more pressure after United Nations Climate Change Conference, 2009. Transition to Low-Carbon Economy is essential road for China, whether respond to the threat of climate change or balance domestic economic development with environmental sustainability. However, China also faces lots of challenges and pressure in the process of transition to Low-Carbon Economy.This thesis combines quantitative method with qualitative methods to do a research about driving force and challenges of developing Low-Carbon Economy in China. Firstly, it discusses the driving forces for China to develop Low-Caron Economy from two aspects-pressures and benefits. Secondly, it investigates challenges that China is likely to face in Low-Carbon Economy development from energy and economic aspect. Finally, it uses cause and effect diagram to explain the bottlenecks of Low-Carbon Economy development in China.Our conclusion is that China faces the bottleneck between challenges and driving force to develop Low-Carbon Economy. And this situation was caused by national actual situations and conditions in China. This explains also why China requested in Copenhagen Conference that “developing countries take appropriated measures to emission control and reduction in terms of receiving the funding and technology support from developed countries. Those emission reduction actions should be done according to the national actual situations and conditions.”

  • 1356.
    Zhu, Zhu
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Zhao, Jiangye
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Risk investigation of logistics management and logistics method in the Chinese non-metallic mineral industry: A Case Study of The Shenzhen Rocky Mountain2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to investigate the risks in logistics management and logistics

    methods for the non-metallic mineral companies. The authors review the current situation of

    logistics management and logistics method from the non-metallic mineral companies and find

    out the problems or risks from these companies. The authors reviewed a few articles that

    evaluate the risks and problems in the non-metallic mineral companies. The authors also had

    several interviews through the Internet with the interviewee, who works as a regional

    manager in the case company. This thesis is a qualitative single case study, the authors search

    for usable information from the Internet, interviews and the authors also review many

    literatures and write about the current situation of the logistics methods, logistics management

    and logistics outsourcing in the non-metallic mineral companies. In the conclusion part, the

    authors give out the answers about the common risks in the literature for logistics

    management and logistics outsourcing, the characteristics of logistics in non-metallic mineral

    companies and the risks and problems of logistics management and logistics outsourcing in

    the non-metallic mineral companies during practice. This part also includes limitation in this

    thesis and it shows the further study, which the authors want to study in the future.

  • 1357.
    Zhuo, Yue
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Measuring inaccessible points in land surveying and analysis of their uncertainty2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 1358.
    Zou, Rucong
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Sun, Hong
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Building Extraction in 2D Imagery Using Hough Transform2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this paper is to find out whether Hough transform if it is helpful to building extraction or not. This paper is written with the intention to come up with a building extraction algorithm that captures building areas in images as accurately as possible and eliminates background interference information, allowing the extracted contour area to be slightly larger than the building area itself. The core algorithm in this paper is based on the linear feature of the building edge and it removes interference information from the background. Through the test with ZuBuD database in Matlab, we can detect images successfully.  So according to this study, the Hough transform works for extracting building in 2D images.

  • 1359.
    Zutautas, Vaidutis
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Charcoal Kiln Detection from LiDAR-derived Digital Elevation Models Combining Morphometric Classification and Image Processing Techniques2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper describes a unique method for the semi-automatic detection of historic charcoal production sites in LiDAR-derived digital elevation models. Intensified iron production in the early 17th century has remarkably influenced ways of how the land in Sweden was managed. Today, the abundance of charcoal kilns embedded in the landscape survives as cultural heritage monuments that testify about the scale forest management for charcoal production has contributed to the uprising iron manufacturing industry. An arbitrary selected study area (54 km2) south west of Gävle city served as an ideal testing ground, which is known to consist of already registered as well as unsurveyed charcoal kiln sites. The proposed approach encompasses combined morphometric classification methods being subjected to analytical image processing, where an image that represents refined terrain morphology was segmented and further followed by Hough Circle transfer function applied in seeking to detect circular shapes that represent charcoal kilns. Sites that have been identified manually and using the proposed method were only verified within an additionally established smaller validation area (6 km2). The resulting outcome accuracy was measured by calculating harmonic mean of precision and recall (F1-Score). Along with indication of previously undiscovered site locations, the proposed method showed relatively high score in recognising already registered sites after post-processing filtering. In spite of required continual fine-tuning, the described method can considerably facilitate mapping and overall management of cultural resources.

  • 1360.
    Älvebrink, Johan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Konceptutveckling av artikelpaletter för effektivare rengöring av detaljer2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Atlas Copco in Tierp focus its production on hand-held tools, fixtured tools and assembly systems. Examples of tools that the company produces are wrenches, screwdrivers, grinders and drills. The production unit in Tierp is the largest production unit in the Industrial Technique business area. The company manufactures articles in many sizes and shapes. The articles are stored and transported in workshop palettes (load carriers). In order to ensure quality standards the articles are cleaned every so often in large industrial washing machines.The rinsing process is not efficient enough when cleaning the company's smaller articles. Palettes which articles are placed in contributes greatly to the lack of efficiency. To get the articles completely clean rinsing must sometimes be done twice.The goal was to develop a new palette concept that enable increased cleanliness after rinsing.Through trial and error method several alternative concepts have been developed and the best selected using Pugh matrix.The selected concept significantly increases the water flow and detail capacity compared to the original palette, but manufacturing costs are estimated to increase.Depending on the manufacturing method selected for making the new palettes, construction design can part. If the palettes are made through 3D-printing it may be advantageous to reduce the height (possibly remove the support pillars) and the mass of the palette to lessen manufacturing costs, while too complex design can increase the cost of machining.I recommended a prototype of the palette too be tested in production to reliably evaluate its properties and quality.

  • 1361.
    Åberg, Christer
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Österberg, Maya
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Den urbana parkens användning och potential för social interaktion: En studie av Stadsträdgården i Gävle2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Urban green-spaces are considered to be more important today than ever before. Parks arenot only beneficial for their positive effects on human health, but also for their social aspects. Parks are consequently considered to be the most suitable environment for encounters between people with different backgrounds and interests. Urban parks have developed from a place where the city-eliteexpressedtheir power to the public into a common place for all. Even though the parksareconsidered to be an open and welcoming place,users are considered to represent a homogenous group of people, which in turn, eliminates the potential of social interaction between different social groups.

    In this thesis a part of the urban park, Stadsträdgården, is investigated with the intention to study and map its use, its users and the existing supply. The methods used in this project are a questionnaire and observations. During the observations elements like counting, mapping, a qualitative experiment and an inventory of the park-attributes have been implemented. In the park, a broad composition of visitors consisting of varied age, gender and ethnicity, can be found. The focus area of this case study is divided into zones through the area of use and the users. In parks, time is an important dimension controlling whether different people will meet or not. Social interaction between strangers occurs in a small amount, and when it does, it depends on a third component, an event or a physical object that calls for a common interest. The parklacksnumerous qualities in the existing supply of the parkaccording to the users. However, it is uncertain towhat extent the public influencesthe planning of existing urban parks in Gävle, and thus if their considerations are ever involved in the planning process.

  • 1362.
    Ågren, Rasmus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Optimerad rendering av fluid meshes2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Simuleringen av vätskor är idag en viktig del inom både film-, spel- och reklamindustrin. Detta kräver dock mycket av hårdvaran vilket saktar ner processen att rendera markant. I detta projekt forskades det inom optimering av renderingstekniker för att göra det lättare att rendera fram kvalitativa resultat när man använder sig av fluids i program för 3D-grafik. Arbetet innehåller en undersökning där testpersoner bedömt ett antal renderingar samt de optimerade inställningar som används till rendering

  • 1363.
    Ågren, Ulrika
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Laserskanning som metod för byggnadsarkeologisk visualisering2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sigtuna är en av de äldsta städerna i landet. Kyrkan S:t Olof är en av flera medeltida kyrkor i staden. Under hösten 2005 utförde Leica Geosystems en demonstrationsmätning med en laserskanner i S:t Olofs ruin. Från museets håll ville man därefter att hela ruinen skulle mätas upp tredimensionellt för att på ett bättre sätt kunna analysera komplicerade kronologiska händelser och förändringar.

    Man har tidigare inom vetenskapsgrenen byggnadsarkeologi upplevt problem med att åstadkomma en fullständig bild av en byggnad genom tvådimensionella ritningar. I en tredimensionell avbildning synliggörs rummet på ett mer fullkomligt och verklighetstroget sätt. Idag har man då och då börjat använda geodetiska metoder och datavisualisering. Detta kommer med stor sannolikhet att ingå i utvecklingen i framtiden. Det finns därför ett behov av att utvärdera användandet av geodetisk mätningsteknik utifrån byggnadsarkeologens önskemål och avsikter samt att undersöka den tredimensionella modellens kapacitet för visualiseringssyften.

    Målsättningen med detta examensarbete är att göra själva inmätningen av S:t Olofs ruin och undersöka hur den tredimensionella modellen ska kunna användas för att visualisera resultatet av den byggnadsarkeologiska analysen.

    Inom ramen för examensarbetet har ruinen efter kyrkan S:t Olof mätts in med hjälp av en laserskanner av fabrikatet Leica HDS 3000. De inmätta punkterna har georefererats till Sigtuna kommuns koordinatsystem. Objekt i punktmolnet har vektoriserats och importerats till dokumentationssystemet Intrasis.

  • 1364.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science. Uppsala University, Department of Information Technology, Sweden .
    Automatic water body extraction from remote sensing images using entropy2015In: Proceedings of the International Multidisciplinary Scientific GeoConference SGEM, 2015, Vol. 4, p. 517-524Conference paper (Refereed)
    Abstract [en]

    This research focuses on automatic extraction of river banks and other inland waters from remote sensing images. There are no up to date accessible databases of rivers and most of other waters objects for modelling purposes. The main reason for that is that some regions are hard to access with the traditional ground through techniques and thus the boundary of river banks are uncertain in many geographical positions. The other reason is the limitations of widely applied method for extraction of water bodies called normalized-difference water index (NDWI). There is a novel approach to extract water bodies, which is based on pixel level variability or entropy, however, the methods work somewhat satisfactory on high spatial resolution images, there is no verification of the method performance on moderate or low resolution images. Problems encounter identification of mixed water pixels and e.g. roads, which are built in attachment to river banks and thus can be classified as rivers. In this work we propose an automatic extraction of river banks using image entropy, combined with NDWI identification. In this study only moderate spatial resolution Landsat TM are tested. Areas of interest include both major river banks and inland lakes. Calculating entropy on such poor spatial resolution images will lead to misinterpretation of water bodies, which all exhibits the same small variation of pixel values as e.g. some open or urban areas. Image entropy thus is calculated with the modification that involves the incorporation of local normalization index or variability coefficient. NDWI will produce an image where clear water exhibits large difference comparing to other land features. We are presenting an algorithm that uses an NDWI prior to entropy processing, so that bands used to calculate it, are chosen in clear connection to water body features that are clearly discernible.As a result we visualize a clear segmentation of the water bodies from the remote sensing images and verify the coordinates with a given geographic reference.

  • 1365.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Early Recognition of Smoke in Digital Video2010In: Advances in Communications, Computers, Systems, Circuits and Devices: European Conference of Systems, ECS'10, European Conference of Circuits Technology and Devices, ECCTD'10, European Conference of Communications, ECCOM'10, ECCS'10 / [ed] Mladenov, V; Psarris, K; Mastorakis, N; Caballero, A; Vachtsevanos, G, Athens: World Scientific and Engineering Academy and Society, 2010, p. 301-306Conference paper (Refereed)
    Abstract [en]

    This paper presents a method for direct smoke detection from video without enhancement pre-processing steps. Smoke is characterized by transparency, gray color and irregularities in motion, which are hard to describe with the basic image features. A method for robust smoke description using a color balancing algorithm and turbulence calculation is presented in this work. Background extraction is used as a first step in processing. All moving objects are candidates for smoke. We make use of Gray World algorithm and compare the results with the original video sequence in order to extract image features within some particular gray scale interval. As a last step we calculate shape complexity of turbulent phenomena and apply it to the incoming video stream. As a result we extract only smoke from the video. Features such shadows, illumination changes and people will not be mistaken for smoke by the algorithm. This method gives an early indication of smoke in the observed scene.

  • 1366.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Indication of Methane Gas in IR-Imagery2011In: Proceedings of IADIS International Conference Computer Graphics, Visualization, Computer Vision and Image Processing 2011, 2011, p. 187-192Conference paper (Refereed)
    Abstract [en]

    There are human produced sources of methane gas, such as waste storages, that contribute to the global warmth and other negative effects. There is not much research on the correlation of such leakage and greenhouse effect. Methane gas is not visible for humans and thus impossible to detect using commercial cameras. Specially designed IR-camera can detect this gas and thus is used in this study. Using digital video taken over a waste disposal place we create a detection algorithm that is sensitive to the spectral and morphological characteristics of methane gas. Different kind of leakage can take place in waste disposal places. In case of small spot leakage there is a reason to assume failure in piping system and in case of widely spread leakage area we can state that it is caused by unsupervised storage of waste and this should be attended immediately. In digital video, background and target gas are distinguished using spectral and morphological classifiers, which are extracted from the analyzed IR-imagery. It is shown that indications of methane gas can be carried out efficiently using image processing techniques and the definition of turbulence of the image.

  • 1367.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Knowledge Based Single Building Extraction and Recognition2014In: Recent Advances in Computer Engineering, Communications and Information Technology / [ed] Josip Music, WSEAS Press , 2014, p. 29-35Conference paper (Refereed)
    Abstract [en]

    Building facade extraction is the primary step in the recognition process in outdoor scenes. It is also a challenging task since each building can be viewed from different angles or under different lighting conditions. In outdoor imagery, regions, such as sky, trees, pavement cause interference for a successful building facade recognition. In this paper we propose a knowledge based approach to automatically segment out the whole facade or major parts of the facade from outdoor scene. The found building regions are then subjected to recognition process. The system is composed of two modules: segmentation of building facades region module and facade recognition module. In the facade segmentation module, color processing and objects position coordinates are used. In the facade recognition module, Chamfer metrics are applied. In real time recognition scenario, the image with a building is first analyzed in order to extract the facade region, which is then compared to a database with feature descriptors in order to find a match. The results show that the recognition rate is dependent on a precision of building extraction part, which in turn, depends on a homogeneity of colors of facades.

  • 1368.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science. Uppsala University, Department of Information Technology, Sweden.
    Mapping of roof types in orthophotos using feature descriptors2018In: International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM: Proceedings of the International Multidisciplinary Scientific GeoConference SGEM, 2018, Vol. 18, p. 285-291Conference paper (Refereed)
    Abstract [en]

    In the context of urban planning, it is very important to estimate the nature of the roof of every building and, in particular, to make the difference between flat roofs and gable ones. This analysis is necessary in seismically active areas. Also in the assessment of renewable energy projects such solar energy, the shape of roofs must be accurately retrieved. In order to perform this task automatically on a large scale, aerial photos provide a useful solution. The goal of this research project is the development of algorithm for accurate mapping of two different roof types in digital aerial images. The algorithm proposed in this paper includes several components: pre-processing step to reduce illumination differences of individual roof surfaces, statistical moments calculation and color indexing. Roof models are created and saved as masks with feature specific descriptors. Masks are then used to mark areas that contain elements of the different roof types (e.g. gable and hip). The final orthophoto visualize an accurate position of each of the roof types. The result is evaluated using precision recall method.

  • 1369.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science. Department of Information Technology, Uppsala University, Uppsala, Sweden.
    Segmentation of shadows and water bodies in high resolution images using ancillary data2016In: 16th International Multidisciplinary Scientific GeoConference SGEM 2016: SGEM2016 Conference Proceedings : Book 2, 2016, Vol. 1, p. 827-834Conference paper (Refereed)
    Abstract [en]

    High spatial resolution imagery is often affected by shadows, both in urban environments with large variations in surface elevation and in vegetated areas. It is a common bias in classification when waters and shadows are registered as the same area. The radiometric response for the shadowed regions should be restored prior to classification. To enable that, separate classes of non-shadowed regions and shadowed areas should be created. Previous work on water extraction using low/medium resolution images, mainly faced two difficulties. Firstly, it is difficult to obtain accurate position of water boundary and secondly, shadows of elevated objects e.g. buildings, bridges, towers and trees are a typical source of noise when facing water extraction in urban regions. In high resolution images the problem of separation water and shadows becomes more prominent since the small local variation of intensity values gives rise to misclassification. This paper proposes a robust method for separation of shadowed areas and water bodies in high spatial resolution imagery using hierarchical method on different scales combined with classification of PCA (Principal Component Analysis) bands, which reduces the effects of radiometric and spatial differences that is commonly associated with the pixel-based methods for multisource data fusion. The method uses ancillary data to aid in classification of shadows and waters. The proposed method includes three steps: segmentation, classification and postprocessing. To achieve robust segmentation, we apply the merging region with three features (PCA bands, NSVDI (Normalized Saturation-value Difference Index) and height data). NSVDI discriminates shadows and some water. In the second step we use hierarchic region based classification to identify water regions. After that step candidates for water pixels are verified by the LiDAR DEM data. As a last step we consider shape parameters such as compactness and symmetry to completely remove shadows.

  • 1370.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Time-space visualisation of Amur river channel changes due to flooding disaster2014In: Proceedings of the International Multidisciplinary Scientific GeoConference SGEM, 2014, Vol. 1:2, p. 873-882Conference paper (Refereed)
    Abstract [en]

    The analysis of flooding levels is a highly complex temporal and spatial assessment task that involves estimation of distances between references in geographical space as well as estimations of instances along the time-line that coincide with  given spatial locations. This work has an aim to interactively explore changes of Amur River boundaries caused by the severe flooding in September 2013. In our analysis of river bank changes we use satellite imagery (Landsat 7) to extract parts belonging to Amur River. We use imagery from that covers time interval July 2003 until February 2014. Image data is pre-processed using low level image processing techniques prior to visualization. Pre-processing has a purpose to extract information about the boundaries of the river, and to transform it into a vectorized format, suitable as inputs subsequent visualization. We develop visualization tools to explore the spatial and temporal relationship in the change of river banks. In particular the visualization shall allow for exploring specific geographic locations and their proximity to the river/floods at arbitrary times. We propose a time space visualization that emanates from edge detection, morphological operations and boundary statistics on Landsat 2D imagery in order to extract the borders of Amur River. For the visualization we use the time-space-cube metaphor. It is based on a 3D rectilinear context, where the 2D geographical coordinate system is extended with a time-axis pointing along the 3rd Cartesian axis. Such visualization facilitates analysis of the channel shape of Amur River and thus enabling for a conclusion regarding the defined problem. As a result we demonstrate our time-space visualization for river Amur and using some amount of geographical point data as a reference we suggest an adequate method of interpolation or imputation that can be employed to estimate value at a given location and time.   

  • 1371.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science. Uppsala University, Department of Information Technology, Sweden.
    Kautz, Marie-Loise
    Technische Universität, Dresden, Germany.
    Data source evaluation for shoreline deliniation applications2017In: International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM: Conference proceedings, 2017, Vol. 17, no 2-3, p. 849-858Conference paper (Refereed)
    Abstract [en]

    This paper proposes an evaluation of data acquired with various sensors and used in coastal water segmentation applications. Correct monitoring of coastal changes in dynamic coastal environments strongly depends on accurate and frequent detection of shoreline position. Automatic shoreline delineation methods are preferable, especially in terms of time, cost, labor intensiveness and difficulties of in-situ measurements. Two main issues have been encountered within this application field, the quality of data and the segmentation algorithms. In this work, potential benefits of various data sources including optical and active sensors for extraction of shorelines have been investigated. The goal with shoreline detection from digital data sources is to obtain information as efficiently as possible and as reliably as necessary. Starting with that observation the paper discusses the effectiveness of coastal information extraction provided different data sources. This question is especially important to address since we observe a fast development of high spatial resolution data acquisition. There are many of segmentation algorithms described in the field of image processing and yet there is currently no single theory or method, no universal segmentation framework, that can be applied on all images to precisely and robustly extract shorelines. Nether there is a uniform standard for the assessment of segmentation results, and this process still largely relies on visual analysis and personal judgment. Out of myriads of image segmentation algorithms, we chose the most frequently and successfully applied within the application field and considering the data sources. In optical sensor data cases, the most frequently used methods are NDWI (Normalized Difference Water Index) and thresholding techniques. We do not aim to create yet another method to segment out the particular objects from remotely sensed data and then tailor it to work efficiently on that data set. Instead, we evaluate the data quality regarding the given application field. The case study is carried out on a 10 km coastal stretch facing the Baltic Sea (Sweden) and belonging to the Municipality of Gävle. In citu measurements were acquired to evaluate the extracted coastal lines and comparisons with reference were performed based on the average mean distance. A conclusion is done regarding the most reliable data source for this particular application of shoreline delineation.

  • 1372.
    Åhlén, Julia
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Liu, Fei
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Evaluation of the Automatic methods for Building Extraction2014In: International Journal Of Computers and Communications, ISSN 2074-1294, Vol. 8, p. 171-176Article in journal (Refereed)
    Abstract [en]

    Recognition of buildings is not a trivial task, yet highly demanded in many applications including augmented reality for mobile phones. Recognition rate can be increased significantly if building façade extraction will take place prior to the recognitionprocess. It is also a challenging task since eachbuilding can be viewed from different angles or under differentlighting conditions. Natural situation outdoor is when buildings are occluded by trees, street signs and other objects. This interferes for successful building façade recognition. In this paper we evaluate the knowledge based approach  to automatically segment out the whole buildingfaçade or major parts of thefaçade. This automatic building detection algorithm is then evaluated against other segmentation methods such as SIFT and vanishing point approach. This work contains two main steps: segmentation of building façades region using two different approaches and evaluation of the methods using database of reference features. Building recognition model (BRM) includes evaluation step that uses Chamfer metrics. BMR is then compared to vanishing points segmentation. In the evaluation mode, comparison of these two different segmentation methods is done using the data from ZuBuD.Reference matching is also done using Scale Invariant Feature Transform. Theresults show that the recognition rate is satisfactory for the BMR model and there is no need to extract the whole building façade for the successful recognition.

  • 1373.
    Öberg, Kristofer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Bevisvärdering i brottmål: Går det tillämpa beslutsanalytiska metoder?2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta arbete behandlas de grundläggande elementen i en brottmålsprocess med särskilt fokus på hur själva bevisvärderingen går till, särskilt då DNA-bevisning ingår i materialet. Dels beskrivs de vanligast förekommande teorierna och vad som sagts om dessa i doktrinen, dels belyses utvalda rättsfall för att visa hur det hela faktiskt fungerar i praktiken. Problematiken kretsar främst kring hur en domstol kommer fram till att ett visst faktums existens är ställt utom rimligt tvivel. Texten föreslår att de nuvarande metoderna för bevisvärdering bör kompletteras med metoder som utvecklats av besluts-, risk- och policyanalysvetare. Mer specifikt föreslås att domstolar i större utsträckning bör använda metoder så som Bayes teorem för att anpassa sina sannolikhetsuppskattningar då nya bevis förs fram i en process.

  • 1374.
    Öholm, Olivia
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Reducering av ställtider2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att vara konkurrenskraftig i dagens globaliserade företagsklimat krävs kostnadseffektiva lösningar som gör det möjligt för företag att möta kundernas krav gällande såväl kvalitet som pris och förmåga att leverera enligt överrenskommelse. Gevalia, ett producerande företag i Gävle, har problem med långa ställtider som markant drar ner deras effektivitet. En universell vedertagen metod för att minska ställtider är SMED, Single minute exchange of die, som anses kunna göras kompatibel i alla typer av industrier.

     

    Syftet med detta examensarbete var således att undersöka orsakerna bakom de långa ställtiderna samt hur dessa kan minskas. Vidare skulle en analysstruktur för ställtidsreduktion skapas.  För att uppnå syftet har intervjuer och observationer gjorts på Gevalia, samt en litteraturstudie kring berörda områden.

     

    Analysstrukturen som skapades är inspirerad av SMED och PDCA-cykeln. Strukturen innefattar även andra metoder som bland annat 5 Why och 5S, samt tar hänsyn till det mänskliga beteendet. Strukturen består av fem steg:

    1. Kartlägg nuläget
    2. Analysera
    3. Skapa förbättringsförslag
    4. Implementera
    5. Utvärdera och återkoppla

     

    Denna struktur användes sedan för att komma fram till förbättringsförslag. Dessa förbättringsförslag blev:

    • Skapa en fixerad utgångspunkt
    • Skapa ett omställningsschema som innefattar hela omställningsprocessen
    • Utbilda och motivera personalen så de gör som det nya tillvägagångssättet säger.

     

    Dessa förbättringsförslag kommer efter examensarbetet tillämpas hos Gevalia.

  • 1375.
    Öhrn, Henrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    NoSQL-databaser och utnyttjandet av en grafdatabas i ett transportnätverk2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den allmänna kunskapen om NoSQL-databaser är begränsad. Den här uppsatsen koncentrerar sig på att sammanställa egenskaper och information om för- och nackdelar som rör dessa databastyper samt relationsdatabaser i en undersökning. Uppsatsen belyser även användningsområden för de olika databastyperna och i en fallstudie testas en grafdatabas förmåga att representera och utföra sökningar av data från ett järnvägsspårnät. Problemområdena undersöktes genom att samla information om olika typer av databaser från artiklar och böcker. Tillämpningsfallet i fallstudien implementerades och testades i en grafdatabas. Resultatet av undersökningen visade att NoSQL-databaser är ett intressant alternativ i vissa fall men att mycket hänsyn måste tas innan man väljer vilken typ av databas som är mest lämpad i den specifika tillämpningen. Resultatet av fallstudien visar att en grafdatabas är särdeles lämpad för att representera och utföra operationer på ett transportnätverk. Detta till stora delar beroende på dess förmåga att representera kopplingarna i ett transportnätverk och i form av de operationerna som finns i grafteorin och som grafmodellen erbjuder.Nyckelord: nosql, relationsdatabas, nyckel/värde-databas, kolumndatabas, objektdatabas, dokumentdatabas, grafdatabas, järnvägsnätverk, transportnätverk

  • 1376.
    Ölander, Jonas
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Löfqvist, Andreas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Utveckling av stödverktyg för livsmedels- & miljöinspektörer2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Gävle kommuns miljö- och livsmedelsinspektörer utför inspektioner hos ca 660 företag och organisationer inom Gävle kommun. Information om organisationer och inspektioner hanteras av ett ärendehanteringssystem. Detta ärendehanteringssystem är inte anpassat för sättet inspektörerna arbetar, vilket gör att de tvingas komplettera viss funktionalitet med ett Exceldokument. Detta Exceldokument löser vissa problem men fungerar inte bra. Detta arbetes syfte och mål är att utveckla en grund till en webbapplikation, i beta-stadiet, vilket ska kunna ersätta det Exceldokument inspektörerna arbetar med och effektivisera deras arbete genom att göra den verksamhetsanpassad. Arbetet resulterade i en webbapplikation vilket effektiviserar inspektörernas arbetssätt. Webbapplikationen är utformad med responsivt gränssnitt. Omdömet av webbapplikationen var positivt och visade på ett förbättrat arbetssätt.

  • 1377.
    Öqvist, Jens
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Jonason, Kristoffer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Interna processer: Modell för ett effektivt returstålsflöde2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The last decade has created an increasing pressure on companies to decrease their impact on the environment and to increase their effectiveness of recycling the company’s resources, especially for the steel industry. Companies have also started to realize the economic aspects of an effective internal reverse logistics. In the past the value of an effective internal reverse logistic was something that companies tend to underestimate and there are few academic studies done in this area.

     

    The purpose of this essay has been to identify key factors to create an effective in plant storage, transport, sorting and handling of returned steel. From these factors a generalized model for creating an effective return steel flow will be developed. The model will then be adjusted to fit a case company, which in this case is Sandvik Materials Technology (SMT) on Sandvik.

     

    The purpose is answered by detailed studies of the literature in the subject combined with interviews and observations on SMT. Through this the key factors have been identified and a model has been developed. The factors that were seen as most crucial were sorting, tied up capital, transport cost and handling cost. These factors have a strong connection between each other and it is important to strike a balance.

     

    By the investigation carried out on SMT it is clear that sorting is the essential factor on the case company, and have the biggest impact on the effectiveness of the returned steel flow. Without functioning sorting there will be a large increase in the quality defect costs. Another factor that was considered important is the number of storage places, where a decrease in the storage places would reduce the tied up capital.

  • 1378.
    Östansjö, Patrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Utveckling av nytt Radiofarmakaregister i Java2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Avdelningen Nuklearmedicin på Gävle sjukhus har problem med att deras befintliga ”Radiofarmakaregister” inte fungerar på Windows 7, som de håller på att uppgradera till. Därför har Gävle sjukhus utlyst ett examensarbete med syftet att lösa problemet med att programmet inte fungerar på Windows 7. Det här projektet gick ut på att utveckla ett nytt program från grunden med de krav sjukhuset ställde. Det nya programmet utvecklades i programmeringsspråket Java. Vid projektets slut uppfylldes de krav som ställdes på projektet

  • 1379.
    Östberg, Patrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Bungebråket: Analys av intresseavvägningar i tvisten om kalkbrytning på Bunge Ducker 1:642017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Konflikten kring kalkbrytning på Bunge Ducker 1:64 har pågått i över 10 år och är ännu inte avgjord när detta examensarbete skrivs. Det geografiska område som berörs går även under benämningen Ojnare eller Ojnareskogen. Två riksintressen står emot varandra; värnandet om naturen och de värden som finns i den brytbara kalken. För domstolarna Miljödomstolen respektive Miljööverdomstolen blev tvisterna en övning i intresseavvägning. I uppsatsen analyseras hur avvägningen genomfördes i två domar som kom till motsatta domslut. Miljödomstolen avslog i en dom från 2009 Nordkalks begäran om tillstånd för kalkbrytning, domen överklagades och Miljööverdomstolen gav i en dom 2010 tillåtlighet. I uppsatsen analyseras även en del av de intresseavvägningar som olika sakägare gjort med speciellt fokus på de sakägare vars intresse inte är givet i och med den verksamhet man bedriver eller sektorsansvar, framförallt länsstyrelsen i Gotlands län och region Gotland. För att fördjupa analysen av länsstyrelsens och regionens beslutsprocess har semistrukturerade intervjuer genomförts med tjänstemän på respektive myndighet. Regeringen fattade i 2015 beslut att under pågående rättsprocesser göra Ojnare till Natura 2000-område. Detta beslut kommer också att analyseras i uppsatsen. I analysen av intresseavvägningarna kommer aggregationsträd och nyttodifferenser att användas så långt det bidrar till förståelse av skeendet.

  • 1380.
    Östberg, Rasmus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Robustness of a neural network used for image classification: The effect of applying distortions on adversarial examples2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Powerful classifiers as neural networks have long been used to recognise images; these images might depict objects like animals, people or plain text. Distorted images affect the neural network's ability to recognise them, they might be distorted or changed due to distortions related to the camera.Camera related distortions, and how they affect the accuracy, have previously been explored. Recently, it has been proven that images can be intentionally made harder to recognise, an effect that last even after they have been photographed.Such images are known as adversarial examples.The purpose of this thesis is to evaluate how well a neural network can recognise adversarial examples which are also distorted. To evaluate the network, the adversarial examples are distorted in different ways and thereafter fed to the neural network.Different kinds of distortions (rotation, blur, contrast and skew) were used to distort the examples. For each type and strength of distortion the network's ability to classify was measured.Here, it is shown that all distortions influenced the neural network's ability to recognise images.It is concluded that the type and strength of a distortion are important factors when classifying distorted adversarial examples, but also that some distortions, rotation and skew, are able to keep their characteristic influence on the accuracy, even if they are influenced by other distortions.

  • 1381.
    Östlund, Eric
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Lernholt, Kim
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Physical Activity Toolkit: Utveckling av en tillgänglig mobilapplikation för kognitivt funktionsnedsatta2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 1382.
    Östlund, Linda
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Inställda förrättningar: Orsaker till inställande i Gävleborg, Dalarna och Jämtlands län 2013-20172018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sometimes obstacles arise in cadastral procedures that make it impossible to carry out the party's claim. An obstacle may be that property formation does not meet the conditions in chapter 3. or 5 chap. property formation (SFS 1970: 988). According to a press release issued by the Government Chancellor on January 19, 2017 (Regeringskansliet, 2017), the average processing time for an cadastral procedures is approximately 47.1 weeks at the Swedish mapping, cadastral and land registration authority (based on the last five years). The Swedish mapping, cadastral and land registration authority was commissioned to work towards shorten cases queues. By detecting obstacles in cadastral proceedings earlier, those cases that are not possible to be implemented can be removed from the case queue and help shorten the processing time.

    By examin cases that have been canceled due to a material barrier, a basis has been provided for reasons of resignation. During the period from 1 January to 31 december 2017, 74 cadastral procedurs were canceled in Gävleborg, Dalarna and Jämtland on due to material barriers.

    In view of the outcome of Klang (Klang, 2010) and the result of this work it can be concluded that the section of the law that most often cause barriers to cadastral procedurs are found in chapter 3 of the Property Formation Act.

    An examination of the property formation at an earlier stage would facilitate the work of the establishment. If obvious defects of appropriateness and conditions that are significantly contrary to the applicable land rules are discovered and can be resolved already at the first examination of the application, it could help reduce the processing time for that case. If not, the case would even be considered impracticable already there. However, in order to be able to make such an assessment at first examination, there is a certain kind of competence that is already lacking today.

  • 1383.
    Östlund, Robert
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Johansson, Patrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Sentence First CAPTCHA: Proposal and study of a text based CAPTCHA scheme2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A major problem on the Internet is automated computer programs abusing services intendedto be used only by humans. Therefore, a method is needed to separate computersfrom humans. Completely Automated Public Turing Test To Tell Computers and HumansApart, or CAPTCHA, is a term used to describe a test that is difficult for computers andeasy for humans to pass and that can be generated and graded automatically. Most of theCAPTCHA schemes currently in use rely on some kind of image or audio recognitionproblem, making them unavailible to the visually and/or audially impaired. Additionally,visual CAPTCHAs can currently be broken with alarmingly high success rates. We proposea CAPTCHA scheme based purely in the text domain which we have named SentenceFirst CAPTCHA. The problem imposed on the users consists of classifying stochasticallygenerated sentences by fluency and legibility and pairs of sentences by semantic coherence.This scheme was implemented and tested by means of several surveys. The answers wereanalysed and the results show that this could very well be a feasible CAPTCHA scheme.

  • 1384.
    Östman, Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Examples of training modules in Gävle, Berlin and Dublin2010Conference paper (Other academic)
  • 1385.
    Östman, Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Introduction of the VESTA GIS project2010Conference paper (Other academic)
  • 1386.
    Östman, Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Network for testing GI services2010In: Proceedings from Symposium GIS Ostrava 2010, 2010, p. 6 s.-Conference paper (Refereed)
  • 1387.
    Östman, Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Verktyg för dataharmonisering baserade på öppen källkod2010In: Kartdagarna 2010 i Jönköping, 14-16 April, 2010Conference paper (Other academic)
  • 1388.
    Östman, Anders
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Bjerkman, Jan
    Future Position X.
    Regional GI Cluster in Support to the SDI Development2010In: International Conference SDI 2010 – Skopje, September 15-17 2010, 2010, p. 209-216Conference paper (Refereed)
  • 1389.
    Östman, Joel
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics.
    Mårtensson, Andreas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics.
    Ledtidsreducering genom värdeflödeskartläggning: Fallstudie på Humm Kombucha2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Organizations striving to grow competitive in the market must today achieve or maintain high productivity, produce the right products, in the right quantity at the right time with high delivery precision to cope with it. By applying effective improvement tools, organizations can reduce lead times, thus achieving higher productivity and quality, which in the long run contributes to lead-time reduction and cost savings. Shorter lead times are today an efficiently competitive weapon, where organizations that hold this can respond faster to market demand and increase customer satisfaction. Over the years, there have been many improvement tools that manufacturing industries can use to reduce lead times. At present, there are few completed and published studies on the use of enhancement tools in just breweries. The purpose is to investigate whether breweries which are a process industry can embrace manufacturing industries' improvement tools and achieve its effects that contribute to lead-time reduction.The methodology that has been the basis for this study is an explanatory case study. Based on this methodology, an approach has naturally arisen, which is a deductive approach. In order to answer the purpose and questions, interviews were conducted which consisted of qualitative semi structured questions, observations in production and measurements of each process step at Humm Kombucha in Gavle. Based on the secondary literature study, improvement tools have been developed that have been successfully used to reduce lead times in manufacturing industries The conclusion that can be established is that breweries can embrace improvement tools and their effects adapted to manufacturing industries. The study has developed improvement suggestions and improvement tools that Humm Kombucha can use in production to eliminate bottlenecks, which in turn reduces lead times.

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