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  • 101. Ahmed, Mobyen
    et al.
    Westin, Jerker
    Högskolan Dalarna, Akademin Industri och samhälle, Datateknik.
    Nyholm, Dag
    Dougherty, Mark
    Högskolan Dalarna, Akademin Industri och samhälle, Datateknik.
    Groth, Torgny
    A fuzzy rule-based decision support system for Duodopa treatment in Parkinson2006Ingår i: 23rd annual workshop of the Swedish Artificial Intelligence Society, Umeå, 2006Konferensbidrag (Refereegranskat)
    Abstract [en]

    A decision support system (DSS) was implemented based on a fuzzy logic inference system (FIS) to provide assistance in dose alteration of Duodopa infusion in patients with advanced Parkinson’s disease, using data from motor state assessments and dosage. Three-tier architecture with an object oriented approach was used. The DSS has a web enabled graphical user interface that presents alerts indicating non optimal dosage and states, new recommendations, namely typical advice with typical dose and statistical measurements. One data set was used for design and tuning of the FIS and another data set was used for evaluating performance compared with actual given dose. Overall goodness-of-fit for the new patients (design data) was 0.65 and for the ongoing patients (evaluation data) 0.98. User evaluation is now ongoing. The system could work as an assistant to clinical staff for Duodopa treatment in advanced Parkinson’s disease.

  • 102.
    Ahmed, Mohamed Kheyr
    Högskolan Dalarna, Akademin Industri och samhälle, Nationalekonomi.
    Taylor rule and monetary policy: Does the Taylor rule describe the monetary policy in Sweden?2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In 1993, economist JB Taylor (1993) observed that the monetary policy in the USA is described by a simple rule, which today is known as the Taylor rule. Since then, many studies were conducted to determine whether Taylor rule explains the monetary policy of central banks all over the world. This study aims to investigate whether the Taylor rule can describe monetary policy in Sweden as initially specified by Taylor (1993). Monetary policy in Sweden from 1995: Q1 to 2018: Q2 is compared to the monetary policy of the USA during the Greenspan years ( 1987: Q4 to 2006: Q1). An ordinary least squares regression method (OLS) is used to estimate the reaction function of the monetary policy of both Sweden and the USA. The results of this study show that the Taylor rule does no describe Monetary policy in Sweden. In contrast, the results show that the US monetary policy during the Greenspan years can be described by the Taylor rule.

  • 103.
    Ahmed, Sadeq Mohamed
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Nationalekonomi.
    Vaziri, Kamran
    Högskolan Dalarna, Akademin Industri och samhälle, Nationalekonomi.
    Price elasticity of demand for cigarettes: The Case of Sweden2014Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Due to health problems and the negative externalities associated with cigarette consumption, many governments try to discourage cigarette consumption by increasing its price through taxation. However, cigarette, like the other addictive goods, is viewed as that it is not sensitive to demand rules and the market forces. This study analyses the effect of price increase on cigarette consumption. We used Swedish time series data from 1970 to 2010.

    Our results reveal that though cigarette is addictive substance its demand is sensitive to changes in the price. Estimates from this study indicate short-run price-elasticity of -0.29 and the long run price elasticity of -0.47.

  • 104.
    Ahmed, Salim Saif Saeed
    Högskolan Dalarna, Akademin Industri och samhälle, Mikrodataanalys.
    Identify the driving behaviour in a parking lot in terms of distance.2018Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Parking a vehicle can often lead to frustration, air pollution and congestion due to limited availability of parking spaces. With increasing population density this problem can certainly increase unless addressed. Parking lots occupy large areas of scarce land resource therefore it is necessary to identify the driving behaviour in a parking lot to improve it further. This Paper tries study the driving behaviour in the parking lot and for this endeavours it conducted direct observation in three parking lots and used GPS data that was collected prior to this study by the University of Dalarna.

    To evaluate the driving behaviour in the parking lot direct observation was conducted to obtain overall indices of the parking lot vehicles movement. The parking route taken by the driver was compared with the optimal path to identify the driving behaviour in parking lot in terms of distance. The collected data was evaluated, filtered and analysed to identify the route, the distance and the time the vehicle takes to find a parking space.

    The outcome of the study shows that driving behaviour in the parking lots varies significantly among the parking user where most of the observed vehicles took unnecessary long time to complete their parking. The study shows that 56% of the 430 observed vehicles demonstrated inefficient driving behaviour as they took long driving path rather the than the optimal path. The study trace this behaviour to two factors, first, the absent of parking guidance in the parking lots and the second is the selectivity of the drivers when choosing the parking space.

    The study also shows that the ability of GPS data to identify the driving behaviour in the parking lots varies based on the time interval and the type of the device that is being used. The small the time interval the more accurate the GPS data in detecting the driving behaviour in the parking lots.

  • 105.
    Ahmed, Toqeer
    Högskolan Dalarna, Akademin Industri och samhälle, Datateknik.
    Load balancing solution and evaluation of F5 content switch equipment2006Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    The Thesis focused on hardware based Load balancing solution of web traffic through a load balancer F5 content switch. In this project, the implemented scenario for distributing HTTPtraffic load is based on different CPU usages (processing speed) of multiple member servers. Two widely used load balancing algorithms Round Robin (RR) and Ratio model (weighted Round Robin) are implemented through F5 load balancer. For evaluating the performance of F5 content switch, some experimental tests has been taken on implemented scenarios using RR and Ratio model load balancing algorithms. The performance is examined in terms of throughput (bits/sec) and Response time of member servers in a load balancing pool. From these experiments we have observed that Ratio Model load balancing algorithm is most suitable in the environment of load balancing servers with different CPU usages as it allows assigning the weight according to CPU usage both in static and dynamic load balancing of servers.

  • 106.
    Aho, Mikaela
    Högskolan Dalarna, Akademin Industri och samhälle, Personal och arbetsliv.
    Vad är attraktivt arbete för personalen på ett vård-, och omsorgsföretag?2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Ett vanligt förekommande problem inom äldreomsorgen svårigheterna att rekrytera personal

    med rätt kompetens. Antalet outbildade ökar inom branschen trots en eftersträvan om att ha

    fler personer som är utbildade. Undersökningar visar att behovet av personal inom branschen

    ökar och antalet personer som utbildar sig till undersköterskor minskar. För att locka till sig

    medarbetare krävs det att ett företag anses vara attraktivt ur medarbetarnas synvinkel och

    även ur potentiella medarbetares synvinkel. För att studera problemet har denna

    undersökning gjorts på ett av ledande företag inom branschen och undersökningen avsåg att

    studera om medarbetarnas syn på attraktivt arbete stämde överens med vad deras chefer

    trodde att deras medarbetare ansåg vara attraktivt arbete.

    Undersökningen har gjorts på fyra olika enheter genom en enkätundersökning som

    medarbetare har besvarat och enheternas närmsta chefer (enhetscheferna) har blivit

    intervjuade. Utöver detta har även intervjuer av biträdande regionchef samt regionchef

    genomförts. Resultatet av undersökningen visade att enhetschefernas syn på attraktivt arbete

    stämde överens med medarbetarnas syn på attraktivt arbete till en viss del. Regionchef samt

    biträdande regionchef hade en djupare förståelse för vilka delar som brister i att framstå som

    attraktiva arbetsgivare.

  • 107.
    Ahonen, Ann- charlotte
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Hellstöm, Maria
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Varför lämnar medlemmarna a-kassan?: En undersökning bland två yrkesgrupper inom den kommunala sektorn i Borlänge2008Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [sv]

    Syftet med denna uppsats är att ta reda på hur många som har lämnat a-kassorna, inom ett par utvalda yrkesgrupper, inom den kommunala sektorn i Borlänge och vad orsaken/orsakerna till utträdet är, samt att ta reda på hur många som har funderat på att lämna a-kassan och orsaken/orsakerna till det För att kunna ta reda på det, har en enkätundersökning gjorts. Enkäten skickades ut till två yrkesgrupper inom den kommunala sektorn i Borlänge, barnskötare och lärare för årskurs 1-3. Resultatet av denna undersökning, redovisas i diagram och till viss del skriftligen. Resultaten visar på att det, procentuellt, sett var fler lärare än barnskötare som lämnat a-kassan, samt att det var fler barnskötare än lärare som funderat på att lämna a-kassan. De främsta orsakerna till att medlemmarna lämnat, eller funderar på att lämna, a-kassan är närmande till pension och den förhöjda avgiften.

  • 108.
    Ahonen, Esa
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Trnavac, Dino
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    The influence of employee empowering on service interface and on employee performance in service organizations 2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 109.
    AIDOO, ERIC
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    MODELLING AND FORECASTING INFLATION RATES IN GHANA: AN APPLICATION OF SARIMA MODELS2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    Ghana faces a macroeconomic problem of inflation for a long period of time. The problem in somehow slows the economic growth in this country. As we all know, inflation is one of the major economic challenges facing most countries in the world especially those in African including Ghana. Therefore, forecasting inflation rates in Ghana becomes very important for its government to design economic strategies or effective monetary policies to combat any unexpected high inflation in this country. This paper studies seasonal autoregressive integrated moving average model to forecast inflation rates in Ghana. Using monthly inflation data from July 1991 to December 2009, we find that ARIMA (1,1,1)(0,0,1)12 can represent the data behavior of inflation rate in Ghana well. Based on the selected model, we forecast seven (7) months inflation rates of Ghana outside the sample period (i.e. from January 2010 to July 2010). The observed inflation rate from January to April which was published by Ghana Statistical Service Department fall within the 95% confidence interval obtained from the designed model. The forecasted results show a decreasing pattern and a turning point of Ghana inflation in the month of July.

  • 110.
    Aishwarya, Veena Aishwarya
    Högskolan Dalarna, Akademin Industri och samhälle, Energiteknik.
    Effects of Soling on the Solar Radiation Sensors for Indian Climatic Conditions2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The satisfaction and elation that accompany the successful completion of any task

    would be incomplete without the mention of the people who have made it possible. It is a great

    privilege to express my gratitude and respect to all those who have guided me and inspired me

    during the period of the project work.

    First and foremost, I express my sincere gratitude to my University professor

    Fiedler Frank, Program Coordinator, Dalarna University, Borlange, Sweden who encouraged

    and permitted me to have my project in the second semester itself.

    I owe a lot to my supervisor Rönnelid Mats, Associate Professor of Energy and

    Environmental Technology, Dalarna University, Borlange, Sweden for his valuable

    suggestions, constructive criticism and encouragement for the project.

    I deem it to be a great privilege in thanking my external supervisor Dr.Richard

    Meyer, Founder and Managing Director (Suntrace GmbH) and Marko Schwandt, Advisor, Solar

    Expert en Suntrace GmbH for giving an opportunity to work under him. Their guidance,

    academic freedom and co-operation have helped me in completing my project.

    My heartfelt thanks to Dr. S. Gomathinayagam, Director General, NIWE and Dr.G.Giridhar,

    Deputy Director General & Head, SRRA department, NIWE for providing me the necessary

    facilities for the completion of my masters project. I am indebted to Dr.Indradip Mitra,Senior

    Technical Advisor at GIZ GmbH and Kaushal Chhatbar, Project Manager, Project

    Development at Suntrace GmbH , for their valuable suggestions and support.

    I also pay my sincere regards to the staffs of SRRA department for their support

    during the period of my project. I owe a lot to my family, who always motivated me and brought

    me to this level. Finally I submit my obeisance to THE ALMIGHTY for constantly supporting

    me and blessing me with the necessary strength to carry out this research.

  • 111.
    AJMAL, KHAN
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    HAN, YANG
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    An Analysis of the Telecommunications Business in China by Linear Regression2010Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In this paper, we study the influence of the National Telecom Business Volume by the data in 2008 that have been published in China Statistical Yearbook of Statistics. We illustrate the procedure of modeling “National Telecom Business Volume” on the following eight variables, GDP, Consumption Levels, Retail Sales of Social Consumer Goods Total Renovation Investment, the Local Telephone Exchange Capacity, Mobile Telephone Exchange Capacity, Mobile Phone End Users, and the Local Telephone End Users. The testing of heteroscedasticity and multicollinearity for model evaluation is included. We also consider AIC and BIC criterion to select independent variables, and conclude the result of the factors which are the optimal regression model for the amount of telecommunications business and the relation between independent variables and dependent variable. Based on the final results, we propose several recommendations about how to improve telecommunication services and promote the economic development.

  • 112.
    AJMAL, KHAN
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    TAHIR MAHMOOD, HASHMI
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Daily Calls Volume Forecasting2010Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    A massive amount has been written about forecasting but few articles are written about the development of time series models of call volumes for emergency services. In this study, we use different techniques for forecasting and make the comparison of the techniques for the call volume of the emergency service Rescue 1122 Lahore, Pakistan. For the purpose of this study data is taken from emergency calls of Rescue 1122 from 1st January 2008 to 31 December 2009 and 731 observations are used. Our goal is to develop a simple model that could be used for forecasting the daily call volume. Two different approaches are used for forecasting the daily call volume Box and Jenkins (ARIMA) methodology and Smoothing methodology. We generate the models for forecasting of call volume and present a comparison of the two different techniques.

  • 113.
    Akbulutgiller, Kazim
    Högskolan Dalarna, Akademin Industri och samhälle, Nationalekonomi.
    Applicatiion of Almost ideal demand system for a pharmaceutical2008Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    This thesis is an application of the Almost Ideal Demand System approach of Deaton and Muellbauer,1980, for a particular pharmaceutical, Citalopram, in which GORMAN´s (1971) multi-stage budgeting approach is applied basically since it is one of the most useful approach in estimating demand for differentiated products. Citalopram is an antidepressant drug that is used in the treatment of major depression. As for most other pharmaceuticals whose the patent has expired, there exist branded and generic versions of Citalopram. This paper is aimed to define its demand system with two stage models for the branded version and five generic versions, and to show whether generic versions are able to compete with the branded version. I calculated the own price elasticities, and it made me possible to compare and make a conclusion about the consumers’ choices over the brand and generic drugs. Even though the models need for being developed with some additional variables, estimation results of models and uncompensated price elasticities indicated that the branded version has still power in the market, and generics are able to compete with lower prices. One important point that has to be taken into consideration is that the Swedish pharmaceutical market faced a reform on October 1, 2002, that aims to make consumer better informed about the price and decrease the overall expenditures for pharmaceuticals. Since there were not significantly enough generic sales to take into calculation before the reform, my paper covers sales after the reform.

  • 114.
    Akram, Muhammad
    Högskolan Dalarna, Akademin Industri och samhälle, Nationalekonomi.
    Do crude oil price changes affect economic growth of India, Pakistan and Bangladesh?: A multivariate time series analysis2012Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This paper analyzes empirically the effect of crude oil price change on the economic growth of Indian-Subcontinent (India, Pakistan and Bangladesh). We use a multivariate Vector Autoregressive analysis followed by Wald Granger causality test and Impulse Response Function (IRF). Wald Granger causality test results show that only India’s economic growth is significantly affected when crude oil price decreases. Impact of crude oil price increase is insignificantly negative for all three countries during first year. In second year, impact is negative but smaller than first year for India, negative but larger for Bangladesh and positive for Pakistan.

  • 115.
    Al Khafaji, Ahmed
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Stenberg, Matteo
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Vikten av kundens förståelse för nyckelleverantörers behov: En kvalitativ undersökning2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund

    Företagsmarknader skiljer ofta sig från den typ av massmarknader som vi ofta finner inom konsumentmarknader. Det som brukar karaktärisera företagsmarknader, är att vi finner ett fåtal kunder och leverantörer som svarar för en stor del av marknadens omsättning. De leverantörer som förser ett företag med produkter eller tjänster som är viktiga för företagets egen leverans kallas nyckelleverantörer. Oftast har dessa leverantörer marknadsanpassade eller unika produkter eller tjänster för de marknader som kunderna opererar inom. Detta innebär för kunderna en möjlig hög grad av beroendeställning till sin leverantör för att vara långsiktigt framgångsrika på marknaden. I en miljö där organisationer strävar efter att utvecklas långsiktigt krävs höga och långsiktiga investeringar med nyckelleverantörer. Att leverantörer idag arbetar med att prioritera, välja och hantera kunder på en marknad där det råder oligopol är inte längre ett nytt fenomen. Kunderna arbetar med att tillgodose leverantörens nöjdhet genom att framhäva sin anpassningsförmåga, samarbetsvilja och långsiktighet för att framstå så attraktiva som möjligt för leverantören.

    Syfte

    Syftet med denna uppsats är att få ökad kunskap om vilka egenskaper i en kundrelation som bidrar till en ökad nöjdhet för en leverantör som har en stark position på marknaden.

    Metod

    För att besvara syftet har en kvalitativ undersökning genomförts mot leverantörer som befinner i en specifik marknadssituation, för att kunna dra en förenklad slutsats. Insamlingen av primär- och sekundärdata har analyserats för att slutligen nå en slutsats.

    Slutsats

    Kunder som uppfyller leverantörers krav, löften och behov kommer anses ha en hög anpassningsförmåga och därmed vara en betydelsefull kund på den marknad där leverantören bedriver sin verksamhet.

  • 116.
    Al Masharqah, Tareq
    Högskolan Dalarna, Akademin Industri och samhälle, Kulturgeografi.
    Political Unrest and its effects in the destination image of Egyptian tourism product2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 117.
    Al Traboulsi, Sara
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Undersköterskors motivation inom åldringsvården2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Undersköterskors arbetsdag varierar från dag till dag beroende på hur dementa äldreboenden mår, känner och agerar. Det finns dagar då äldreboende är glada och positiva men andra dagar kan de vara oroliga, nervösa och aggressiva. Syftet med studien är “vad är det som motiverar undersköterskor till att arbeta med dementa äldreboende inom åldringsvården”. Det studien visar är om undersköterskor ska kunna klara av svåra dagar krävs det bra samarbete mellan kollegorna. Undersköterskor motiveras genom samarbete och uppskattning av äldreboende och anhöriga. När undersköterskor inte upplever ett bra samarbete eller uppskattning blir de mindre motiverade till arbetet och ineffektiva. Denna studie visar att undersköterskor föredrar att själva påverka sina arbetsuppgifter och inte vara styrda. Styrning vill undersköterskor undvika och föredrar att kunna arbeta fritt med äldreboende. Resultatet visar att undersköterskor anser att fritt arbete är det bästa för att hjälpa dementa äldreboenden på bästa sätt.

  • 118.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    An efficient algorithm for the pseudo likelihood estimation of the generalized linear mixed models (GLMM) with correlated random effects2009Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents a two-step pseudo likelihood estimation technique for generalized linear mixed models with correlated random effects. The proposed estimation technique does not require reparametarisation of the model. Multivariate Taylor's approximation has been used to approximate the intractable integrals in the likelihood function of the GLMM. Based on the analytical expression for the estimator of the covariance matrix of the random effects, a condition has been presented as to when such a covariance matrix can be estimated through the estimates of the random effects. An application of the model with a binary response variable has been presented using a real data set on credit defaults from two Swedish banks. Due to the use of two-step estimation technique, proposed algorithm outperforms the conventional pseudo likelihood algorithms in terms of computational time.

  • 119.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    An efficient estimation of the GLMM with correlated random effects2008Ingår i: COMPSTAT'2008: International Conference on Computational Statistics / [ed] Moudud, Alam, Porto-Portugal, 2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents a two-step pseudo likelihood estimation technique for the generalized linear mixed models (GLMM) with random effects being correlated (possibly between subjects). Due to the use of the two-step estimation technique the proposed algorithm outperforms the conventional pseudo likelihood algorithms, e.g. Wolfinger and O’Connell (1993), in terms of computational time. Moreover, it does not require any reparametarisation of the model such as Lindstrom and Bates (1989). Multivariate Taylor’s approximation has been used to approximate the intractable integrals in the likelihood function of the GLMM. Based on the analytical expression for the estimator of the covariance matrix of the random effects, a condition has been presented as to when such a covariance matrix can be estimated through the estimates of the random effects. An application of the estimation technique with a binary response variable is presented using a real data set on credit defaults.

  • 120.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Feasible computation of the generalized linear mixed models with application to credit risk modelling2010Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis deals with developing and testing feasible computational procedures to facilitate the estimation of and carry out the prediction with the generalized linear mixed model (GLMM) with a scope of applying them to large data sets. The work of this thesis is motivated from an issue arising in credit risk modelling. We have access to a huge data set, consisting of about one million observations, on credit history obtained from two major Swedish banks. The principal research interest involved with the data analysis is to model the probability of credit defaults by incorporating the systematic dependencies among the default events. In order to model the dependent credit defaults we adopt the framework of GLMM which is a popular approach to model correlated binary data. However, existing computational procedures for GLMM did not offer us the flexibility to incorporate the desired correlation structure of defaults events. For the feasible estimation of the GLMM we propose two estimation techniques being the fixed effects (FE) approach and the two-step pseudo likelihood approach (2PL). The preciseness of the estimation techniques and their computational advantages are studied by Monte-Carlo simulations and by applying them to the credit risk modelling. Regarding the prediction issue, we show how to apply the likelihood principle to carry out prediction with GLMM. We also provide an R add-in package to facilitate the predictive inference for GLMM.

  • 121.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Feasible estimation of generalized linear mixed models (GLMM) with weak dependency between groups2010Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents a two-step pseudo likelihood estimation technique for generalized linear mixed models with the random effects being correlated between groups. The core idea is to deal with the intractable integrals in the likelihood function by multivariate Taylor's approximation. The accuracy of the estimation technique is assessed in a Monte-Carlo study. An application of it with a binary response variable is presented using a real data set on credit defaults from two Swedish banks. Thanks to the use of two-step estimation technique, the proposed algorithm outperforms conventional pseudo likelihood algorithms in terms of computational time.

  • 122.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Industry shocks and empirical evidences on defaults comovement2009Rapport (Övrigt vetenskapligt)
    Abstract [en]

    It is commonly agreed that the credit defaults are correlated. However, the mechanism of such dependence is not yet fully understood. This paper contributes to the current understanding about the defaults comovement in the following way. Assuming that the industries provides the basis of defaults comovement it provides empirical evidence as to how such comovements can be modeled using correlated industry shocks. Generalized linear mixed model (GLMM) with correlated random effects is used to model the defaults comovement. Empirical evidences are drawn through analyzing individual borrower level credit history data obtained from two major Swedish banks between the period 1994-2000. The results show that the defaults are correlated both within and between industries but not over time (quarters). A discussion has also been presented as to how a GLMM for defaults correlation can be explained.

  • 123.
    Alam, Moudud
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Likelihood prediction for generalized linear mixed models under covariate uncertainty2014Ingår i: Communications in Statistics - Theory and Methods, ISSN 0361-0926, E-ISSN 1532-415X, Vol. 43, nr 2, s. 219-234Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the techniques of likelihood prediction for the generalized linear mixed models. Methods of likelihood prediction is explained through a series of examples; from a classical one to more complicated ones. The examples show, in simple cases, that the likelihood prediction (LP) coincides with already known best frequentist practice such as the best linear unbiased predictor. The paper outlines a way to deal with the covariate uncertainty while producing predictive inference. Using a Poisson error-in-variable generalized linear model, it has been shown that in complicated cases LP produces better results than already know methods.

  • 124.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Computionally feasible estimation of the covariance structure in generalized linear mixed models2008Ingår i: Journal of Statistical Computation and Simulation, ISSN 0094-9655, E-ISSN 1563-5163, Vol. 78, nr 12, s. 1229-1239Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we discuss how a regression model, with a non-continuous response variable, which allows for dependency between observations, should be estimated when observations are clustered and measurements on the subjects are repeated. The cluster sizes are assumed to be large. We find that the conventional estimation technique suggested by the literature on generalized linear mixed models (GLMM) is slow and sometimes fails due to non-convergence and lack of memory on standard PCs. We suggest to estimate the random effects as fixed effects by generalized linear model and to derive the covariance matrix from these estimates. A simulation study shows that our proposal is feasible in terms of mean-square error and computation time. We recommend that our proposal be implemented in the software of GLMM techniques so that the estimation procedure can switch between the conventional technique and our proposal, depending on the size of the clusters.

  • 125.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Chen, Rui
    Liang, Yuli
    How to determine the progression of young skiers?2008Ingår i: CHANCE: New Directions for Statistics and Computing, ISSN 0933-2480, Vol. 21, nr 4, s. 13-19Artikel i tidskrift (Refereegranskat)
  • 126.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Linde, Olof
    Sweco Eurofutures.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Sandén, Peter
    Sweco Eurofutures.
    Wing, Stefan
    Sweco Eurofutures.
    Utvärdering av det arbetsmarknadspolitiska projektet "Volvo Cars och dess underleverantörer"2012Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Denna rapport är en utvärdering av det arbetsmarknadspolitiska projektet "Volvo Cars och dess underleverantörer", som har genomförts av Arbetsförmedlingen i samarbete med Skolverket och Svenska ESF-rådet. Den 5 juni 2009 ansökte Sveriges regering om medel hos den Europeiska globaliseringsfonen (EGF)2 för att kunna erbjuda åtgärder för personer som blivit uppsagda från Volvo Cars AB och dess underleverantörer. Syftet med projektet var att kunna erbjuda de som blivit uppsagda kompetensutveckling, nya yrkeskunskaper och möjlighet att etablera egna företag.

    På operativ nivå drevs projektet i samverkan mellan Arbetsförmedlingen och den kom-munala yrkesvuxenutbildningen ("Yrkesvux"). Yrkesvux i Göteborgs kommun fick i upp-drag av Skolverket att samordna den del av verksamheten som berörde kommunal yr-kesvuxenutbildning. Projektet startade 1 januari 2010 och avslutades 31 maj 2011. Enligt kommissionens beslut fick medel även användas retroaktivt för insatser som hade givits till de uppsagda i form av olika arbetsmarknadsutbildningar, det s.k. snabbspåret, under 2009 innan projektet hade startat.

    Av nästan 5 000 individer i målgruppen som registrerade sig vid Arbetsförmedlingen del-tog knappt en fjärdedel i projektets insatser (exkl. vägledning). Av dessa gick 55 procent i aktiviteter enbart genom Arbetsförmedlingen, 37 procent enbart genom Yrkesvux och åtta procent genom både Arbetsförmedlingen och Yrkesvux. De vanligaste förekommande utbildningsinriktningarna var industri och bygg, fordonsindustri, transport och magasine-ring, omvårdnad och handel.

  • 127.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Har kommunala sommarjobb under gymnasieåren en positiv effekt på arbetskarriären senare i livet?2013Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Att erbjuda sommarjobb till ungdomar ses i många länder som ett sätt att förbättra ungdomars möjligheter att komma in och etablera sig på arbetsmarknaden. I Sverige erbjuder de flesta kommuner, delvis finansierat med statliga medel, sommarjobb till ungdomar. Den forskning som finns kring effekten av sommarjobb för ungdomar pekar dock i olika riktningar och lider ofta av metodproblem. Vi undersöker här med bättre metodologiska förutsättningar om kommunala sommarjobb för gymnasieungdomar i Falu kommun har någon positiv effekt på den postgymnasiala inkomstutvecklingen. Vi följer 2 650 ungdomar som, under första året i gymnasiet, ansökte om kommunalt sommarjobb. Vi följer dem tills de når en ålder av som mest 29 år. De kommunala sommarjobben fördelades genom ett lotteriförfarande där alla som ansökte hade lika stor chans att bli tilldelad ett sommarjobb. Vi finner ingen programeffekt för män. För kvinnor upptäcker vi en positiv effekt och då speciellt för kvinnor med låga betyg från grundskolan.

  • 128.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    High-School Students´ Summer Jobs and their Ensuing Labor Market Achievement: the Long Term Effect2013Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In part because of high and persistent youth unemployment, adolescent students’ transition from school to work is an important policy and research topic. Many countries have implemented public programs offering summer jobs or work while in high-school as measures to smooth the transition. While the immediate effect of the programs on school attendance, school grades, and disposable income is well documented, their effect on the transition to the labor market remains an open question. Observational studies have shown strong positive effects of summer jobs, but also that the estimated effect is highly vulnerable to selection bias. In this paper, some 3700 high-school students applying for summer jobs in the period 1995-2003,via a program, are followed to 30 years of age. A quarter of the applicants were randomly offered a summer job each year. Among the remaining students, 50% had a (non-program related) summer job while in high-school. We find the income, post high-school, for the offered and non-offered groups to be similar and conclude that the effect of summer jobs on the transition to the labor market is inconsequential.

  • 129.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Sommarjobb, arbetslivserfarenhet och framtida arbetsinkomst2015Ingår i: Arbetsmarknad & Arbetsliv, ISSN 1400-9692, Vol. 21, nr 4, s. 26-40Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    De flesta kommuner erbjuder sommarjobb till gymnasieungdomar. Vi har undersökt om denna arbetslivserfarenhet påverkar flickors framtida arbetsinkomster. Vi följde 1 447 flickor i fem till tolv år efter avslutat gymnasium. Flickorna hade under sitt första gymnasieår ansökt och slumpmässigt tilldelats sommarjobb av Falu kommun. Effekten av sommarjobbserfarenheten var positiv och betydande för dem.

  • 130.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    The effect of summer jobs on post-schooling incomes2013Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In part because of high youth unemployment, students’ transition from school to work is an important policy and research topic. Public programs offering summer jobs or work while in high school as measures to smooth the transition is commonplace. The immediate effect of the programs on school attendance, school grades, and disposable income is well documented. However, their effect on the transition to the labor market remains unsettled, partly because of a potential selection bias in previous observational studies. In this paper, 2650 first graders of high school in Falun Council, Sweden, randomly allotted summer jobs via a program in the years of 1997-2003, are followed ten years after graduation. The program led to a substantially larger accumulation of work experience while in high school for offered (particularly weak academically performing) females, but not for offered males. Hence, the immediate program effect was heterogeneous. Females were used to estimate the causal effect of work experience while in high school on post-schooling incomes. The (statistically) significant estimate implies an elasticity of 0.4. Work experience while in high school seems to be of future benefit, but the elasticity is potentially inflated due to heterogeneous effects that we were unable to account for.

  • 131.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    The program and treatment effect of summer jobs on girls’ post-schooling incomes2014Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Public programs (of disputed effect) offering summer jobs or work while in high school to smooth the transition from school to work is commonplace. In this paper, 1447 girls in their first grade of high school between 1997-2003 and randomly allotted summer jobs via a program in Falun (Sweden) are followed 5-12 years after graduation. The program led to a substantially larger accumulation of income while in high school. The causal effect of the high school income on post-schooling incomes was substantial and statistically significant. The implied elasticity of 0.4 is however potentially inflated dueto heterogeneous effects.

  • 132.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Nääs, Ola
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    The program and treatment effect of summer jobs on girls’ post-schooling incomes2015Ingår i: Evaluation review, ISSN 0193-841X, E-ISSN 1552-3926, Vol. 39, nr 3, s. 339-359Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Public programs offering summer jobs to smooth the transition from school to work is commonplace. However, the empirical support for summer jobs is limited. This article exploits the availability of registered individual information and random allocation to summer jobs to provide empirical evidence on this issue. 

    Objectives: To identify the effect of summer job programs on the post-schooling incomes of the intended participants. Also to identify the effect of sophomore girls' high school work experience on their post-schooling incomes. 

    Research design: In this article, 1,447 sophomore girls from 1997 to 2003 are followed 5-12 years after graduation. They all applied to Falun municipality's (Sweden) summer job program, and about 25% of them were randomly allotted a job. The random allocation to a summer job is used to identify the causal effect of sophomore girls' high school income on their post-schooling incomes. 

    Subjects: All the 1,447 sophomore girls who applied to Falun municipality's summer job program during 1997-2003. 

    Measures: Annual post-schooling income is used as an outcome measure. The work experience of girls in high school is also measured in terms of total income while in high school. 

    Results: The program led to a substantially larger accumulation of income during high school as well as 19% higher post-schooling incomes. The high school income led to a post-schooling income elasticity of 0.37 which is, however, potentially heterogeneous with regard to academic ability. 

    Conclusions: Both the program effect and the causal effect of high school income on post-schooling incomes were substantial and statistically significant.

  • 133.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Hao, Chengcheng
    Carling, Kenneth
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Review of the literature on credit risk modeling: development of the past 10 years2010Ingår i: Banks and Bank Systems, ISSN 1816-7403, Vol. 5, nr 3, s. 43-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper traces the developments of credit risk modeling in the past 10 years. Our work can be divided into two parts: selecting articles and summarizing results. On the one hand, by constructing an ordered logit model on historical Journal of Economic Literature (JEL) codes of articles about credit risk modeling, we sort out articles which are the most related to our topic. The result indicates that the JEL codes have become the standard to classify researches in credit risk modeling. On the other hand, comparing with the classical review Altman and Saunders(1998), we observe some important changes of research methods of credit risk. The main finding is that current focuses on credit risk modeling have moved from static individual-level models to dynamic portfolio models.

  • 134.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Maengseok, Noh
    Department of Statistics, Pukyong National University, South Korea.
    Lee, Youngjo
    Department of Statistics, Seoul National University, South Korea.
    Likelihood estimate of treatment effects under selection bias2013Ingår i: Statistics and its Interface, ISSN 1938-7989, E-ISSN 1938-7997, Vol. 6, nr 3, s. 349-359Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We consider methods for estimating the causal effects of treatment in the situation where the individuals in the treatment and the control group are self selected, i.e., the selection mechanism is not randomized. In this case, a simple comparison of treated and control outcomes will not generally yield valid estimates of casual effect. The propensity score method is frequently used for the evaluation of treatment effect. However, this method is based on some strong assumptions, which are not directly testable. In this paper, we present an alternative modelling approach to draw causal inferences by using a shared random-effect model and the computational algorithm to draw likelihood based inference with such a model. With small numerical studies and a real data analysis, we show that our approach gives not only more efficient estimates but also is less sensitive to model misspecifications, which we consider, than existing methods.

  • 135.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Noh, Maengseok
    Department of Statistics, Pukyong National Univeristy.
    Lee, Youngjo
    Department of Statistics, Seoul National Univeristy.
    Likelihood estimate of treatment effects under selection bias2012Rapport (Övrigt vetenskapligt)
    Abstract [en]

    We consider methods for estimating causal effects of treatment in the situation where the individuals in the treatment and the control group are self selected, i.e., the selection mechanism is not randomized. In this case, simple comparison of treated and control outcomes will not generally yield valid estimates of casual effects. The propensity score method is frequently used for the evaluation of treatment effect. However, this method is based onsome strong assumptions, which are not directly testable. In this paper, we present an alternative modeling approachto draw causal inference by using share random-effect model and the computational algorithm to draw likelihood based inference with such a model. With small numerical studies and a real data analysis, we show that our approach gives not only more efficient estimates but it is also less sensitive to model misspecifications, which we consider, than the existing methods.

  • 136.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Rönnegård, Lars
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Shen, Xia
    Karolinska Institutet.
    Fitting conditional and simultaneous autoregressive spatial models in hglm2015Ingår i: The R Journal, ISSN 2073-4859, Vol. 7, nr 2, s. 5-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a new version (> 2.0) of the hglm package for fitting hierarchical generalized linear models (HGLMs) with spatially correlated random effects. CAR() and SAR() families for conditional and simultaneous autoregressive random effects were implemented. Eigen decomposition of the matrix describing the spatial structure (e.g., the neighborhood matrix) was used to transform the CAR/SAR random effects into an independent, but eteroscedastic, Gaussian random effect. A linear predictor is fitted for the random effect variance to estimate the parameters in the CAR and SAR models. This gives a computationally efficient algorithm for moderately sized problems.

  • 137.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Rönnegård, Lars
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Shen, Xia
    Swedish University of Agricultural Sciences, Uppsala.
    Fitting spatial models in the R package: hglm2014Rapport (Övrigt vetenskapligt)
    Abstract [en]

    We present a new version of the hglm package for fittinghierarchical generalized linear models (HGLM) with spatially correlated random effects. A CAR family for conditional autoregressive random effects was implemented. Eigen decomposition of the matrix describing the spatial structure (e.g. the neighborhood matrix) was used to transform the CAR random effectsinto an independent, but heteroscedastic, gaussian random effect. A linear predictor is fitted for the random effect variance to estimate the parameters in the CAR model.This gives a computationally efficient algorithm for moderately sized problems (e.g. n<5000).

  • 138.
    Alam, Moudud
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Statistik.
    Wang, Yu
    When are non-experimental estimates close to experimental estimates?: Evidence from a study of summer job effects in Sweden2007Rapport (Övrigt vetenskapligt)
  • 139.
    Alayan, Sophia
    Högskolan Dalarna, Akademin Industri och samhälle, Energiteknik.
    Design of a PV-Diesel Hybrid System with Unreliable Grid Connection in Lebanon2016Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis is a study on integration of photovoltaic generators into an existing diesel-unreliable grid connected system at the Lebanese village of Khiam. The main goal of implementing PV-diesel hybrid system is to reduce diesel consumption and the import of fossil fuel used in electricity power supply. Before designing the system, it is necessary to create a load profile for 120 households and pre-design the size of the PV generator, the capacity of storage system and inverter type/size selection. The load profile data is based on the average of monthly energy consumption gathered from Khiam village households.

    Detailed simulations and financial analysis are performed with HOMER to compare different systems and their viability. The simulations include four different designs starting from the existing system, diesel generator with unreliable grid, followed by PV generator and unreliable grid, PV and diesel generator and ended with the complete hybrid system. Once the Hybrid system is determined a detailed design is done to optimize the lowest cost PV-diesel hybrid system. The final simulated PV-diesel hybrid system is suggested with a PV capacity of 270 kWp, existing diesel capacity with 200 kVA, an inverter output of 115 kW and battery bank nominal capacity is 1872 kWh. The system renewable fraction is 53% and the project life cycle is 25 years. The PV-diesel hybrid system is projected to produce electricity at a cost of 0.12 USD/kWh. This cost is significantly lower than the 0.26 USD/kWh paid to the diesel operator, as well as lower than 0.13 USD/kWh paid to the utility grid.

    In addition, and according to the given information from the owner, an estimated diesel consumption of 104000 ltr/year, the simulation result shows diesel consumption at 40000 ltr/year. The reduced carbon dioxide production by 65%, from 776 to 272 tons per year, provides further justification for the PV installation in a commercial PV-diesel hybrid system.

  • 140. Albaric, Michael
    et al.
    Bales, Chris
    Högskolan Dalarna, Akademin Industri och samhälle, Energi och miljöteknik.
    Drueck, Harald
    Gagnepain, B.
    Kuhness, G.
    Letz, T.
    Mette, B.
    Thür, A.
    Nielsen, J.E.
    Papillon, P.
    Solar CombiSystems Promotion and Standardisation (COMBISOL project)2008Ingår i: Eurosun 2008, Lisbon, 2008Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Solar combisystems (SCS) are solar heating installations providing space heating as well as domestic hot water in buildings. Within a global solar thermal energy strategy, SCS are a key element to decrease the fossil energy demand for heating in existing and new buildings. This project will help to reduce the use of fossil fuels and hence also the emission of greenhouse gases. During 3 years December 2007 – December 2010), experts from research, testing institutes and industry will work in the aim to encourage an accelerated deployment of SCS market – hence a higher share of heat produced by solar energy - and promote an improved quality of the installed systems.

  • 141.
    Albatrok, Husam
    Högskolan Dalarna, Akademin Industri och samhälle, Byggteknik.
    Våningspåbyggnad i trä på befintligt betong bostadshus2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Under åren 1965–1975 valde politikerna att starta ett stort bostadsbygge som resulterade i att en miljon bostäder byggdes på 10 år. Det kom att kallas miljonprogrammet. Tjärna Ängar är ett område som ligger i Borlänge där miljonprogramsbygget ägde rum. Området har 1179 lägenheter i 3-vånings lamellhus och området Tjärna ängar är uppdelat i tre olika kvarter: Kornstigen, Klövern och Plogstigen. Dessa är byggda intill Tjärna centrum, med bra bussförbindelser till resten av Borlänge.

    Syftet med det här arbetet var att fram en våningspåbyggnad för ett befintligt lamellhus i betong. Referensbyggnaden är på Kornstigen 25 Med hjälp av ritningar kommer den befintliga byggnaden att studeras. Informationssökning kommer att göras kring ämnet gällande våningspåbyggnader och miljonprogrammets historia samt uppbyggnation. Väggar tak och bjälklag kommer att tas fram och en tillbyggnad för hissen. Slutligen görs en modell i ett cad som illustrerar resultatet.

    Resultatet av våningspåbyggnaden blev en loftgång i trä med sammanlagt 10 lägenheter. 2 hörnlägenheter blev 3rok medan resterande blev 2 rok i varierande ytor

    Våningspåbyggnader i trä ett bra sätt för att kunna bygga på höjden, men många aspekter bör kontrolleras innan ett våningspåbygge sker.

  • 142.
    Aleblad, Anna
    Högskolan Dalarna, Akademin Industri och samhälle, Grafisk teknik.
    Informationsbroschyr åt Brombergs Bokförlag2005Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
  • 143.
    Alem, Tesfaom
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Informatik.
    Lind, William
    Högskolan Dalarna, Akademin Industri och samhälle, Informatik.
    Organisationers utmaningar och åtgärder vidframtagandet av samtyckestexter samt dess behandling av personuppgifter i enlighet med dataskyddsförordningen (GDPR)2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Utvecklingen av digital teknik tillsammans med nya affärsmodeller har nått nya nivåer

    under de senaste åren vilket har resulterat i att behandlingen av personuppgifter både ökat

    och förändrats. Problematiken med detta innefattar att den personliga integriteten i större

    utsträckning kränks. I syfte att harmonisera behandlingen av personuppgifter och att stärka

    skyddet av den personliga integriteten har EU infört en ny dataskyddsförordning.

    Förordningen träder i kraft den 25 maj 2018 och ska tillämpas i nationell lagstiftning

    vilket gör att den svenska personuppgiftslagen ersätts.

    Syftet med studien var att identifiera vilka åtgärder ett antal organisationer vidtagit för att

    följa dataskyddsförordningens regler samt vilka utmaningar som kan uppstå i

    omställningen. Studien är avgränsad till samtyckestexter och behandling av

    personuppgifter. Studien är kvalitativ och vi har med hjälp av intervjuer tagit del av ett

    antal organisationers syn på utmaningar och åtgärder gällande formuleringar av

    samtyckestexter och dess personuppgiftsbehandling.

    Slutsatsen i denna studie visar att samtliga organisationerna har problem att formulera

    samtyckestexter på ett informativt sätt vilket dataskyddsförordningen kräver.

    Organisationerna ser även utmaningar i behandlingen av personuppgifter. Dessa

    utmaningar består av komplexa IT-system innehållande mängder av personuppgifter som

    idag inte kan hanteras i enlighet med dataskyddsförordningen då relevant systemstöd

    saknas.

  • 144.
    Alfadel, Usama
    Högskolan Dalarna, Akademin Industri och samhälle, Energiteknik.
    Analysing the Peak Shaving Effect and the Increase in SelfConsumption and Self Sufficiencyof Battery Storage When Coupledto a Single Family House2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The aims of the study were to investigate the increase in self-consumption and self-sufficiency and the peak shaving effect of batteries when added to a PV system dimensioned to supply the electric demand of a low energy house built in Sweden. The simulated batteries were Li-ion and the study had a 15-minutes temporal resolution. The study took only the technical aspect of batteries into account and disregarded the economic aspect. A data set of measurements from two near-zero-energy houses built by the Research Institute of Sweden (RISE) was used as inputs. The first house provided measured load profile for an automated load and measured PV production from its 3.6 kW

    p system, the second house provided a load profile for a normal human interactive load. The measured PV production from the 3.6 kWp PV system was compared to the PV production from a simulated 3.6 kWp system taken from PVsyst and System Advisor Model (SAM) and by using different weather data profiles for the simulations. The global irradiance values from the used weather profile data were compared to demonstrate the difference in its values and its effect on the simulated PV production. This comparison between the measured PV production and the simulated one was done because most of the PV simulation software does not take measured PV production as input but they simulate their own PV production based on their built-in weather data; including the software used in this study SAM. The first house with the automated load had an annual energy consumption of Ca. 3600 kWh / Year. The second house with its human interactive load had an annual energy consumption of Ca. 6000 kWh / Year. The load profile was taken as a whole and then divided to different types; heat pump, ventilation and remaining load which represents house hold services. The effect of the input load profile types and its temporal resolution was clarified; this effect came in consistency to what was concluded from the literature review. Different simulations were done varying battery sizes, voltage level, coupling method, dispatch algorithm and other parameter. Three different dispatch algorithms were used for the simulations; two are designed for peak shaving and are built-in tools in SAM while the third algorithm is called Target Zero and designed for maximizing self-consumption and self-sufficiency, it was found in a reference so it was executed in MS Excel. Each of the algorithms used was found to affect both the peaks and the self-consumption and self-sufficiency of the system after adding the batteries compared to before, one as a major effect and the other as a byproduct effect. The peak shaving results varied by varying the batteries and the dispatch algorithm used, for the peak shaving algorithms from SAM, a general decrease in peaks value was reached. For the Target Zero algorithm which optimizes on self-consumption and self-sufficiency, a decrease in the number of the peaks was reached. Both decreases happened by increasing battery sizes. For the self-consumption and self-sufficiency effect, an increase happened with its highest value for 7.2 kWh batteries and by using the three different algorithms. The effect of the load type was also demonstrated by comparing the simulations results for the heat pumps from both houses since both heat pumps were found to have the highest effect on the results. The study was concluded by emphasizing the added values of batteries when coupled to a behind-the-meter PV system. The study could have been more precise and added more information to this field if it had a 1 minute temporal resolution simulations, but patching one minute temporal resolution load profile takes a long time. Working with one minute load profile requires one minute weather profile for the PV simulation which is normally only commercial. Also, having a weather station installed at the house to measure the solar irradiance to be used in the simulation instead of using different weather profiles would have added more accuracy to this paper.

  • 145.
    Alfredsson, Clara
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Grafisk teknologi.
    Pettersson, Karin
    Högskolan Dalarna, Akademin Industri och samhälle, Grafisk teknologi.
    Sportevenemangets nyhetsbrev: Råd om utformningen av nyhetsbrev2015Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Samhället blir allt mer digitaliserat, vilket lett till att en stor mängd företagbehövt förändra sin marknadsföring. Många företag marknadsför sig idaggenom digitala kanaler, en av dessa är e-post. Ett sätt att marknadsföra sig viae-post är med nyhetsbrev. Forskningen om e-postmarknadsföring är betydligtmer omfattande än den specifikt om nyhetsbrev, vilket gör nyhetsbrev till ettintressant ämne att studera närmre. Syftet med studien är att undersöka vad rådangående utformningen av nyhetsbrev behandlar och om råden som finns äranpassade specifikt för sportevenemangs nyhetsbrev. Studiens syfte är även attgranska om Skid-VM:s allmänna nyhetsbrev följer några av de generella rådensom valts ut och om tillämpningen av råden föredras av mottagarna eller inte.För att besvara studiens frågeställningar har en kartläggning, en jämförelse ochen enkätundersökning genomförts. Kartläggningen gjordes genom eninformationssökning och 65 råd hittades. Sex generella råd valdes ut ochjämfördes mot Skid-VM:s allmänna nyhetsbrev. Nya modifierade varianter pådelar av nyhetsbrevet formgavs utifrån om den ursprungliga delen av Skid-VM:s nyhetsbrev följde det generella rådet eller inte. De modifieradevarianterna och de ursprungliga sattes ihop till bildpar. I enkätundersökningensom publicerades på Facebook-sidor och grupper administrerade av Skid-VMfick deltagarna sedan välja vilken variant de föredrog. Kartläggningenresulterade i slutsatserna att många av råden behandlade utformningen avnyhetsbrevets texter och att råd om utformningen av nyhetsbrev specifiktanpassade för sportevenemang var sällsynta. Slutsatserna blev även att Skid-VM:s nyhetsbrev följde fyra av de sex generella råden och att varianten avnyhetsbreven som följde det generella rådet föredrogs i tre av sex fall.

  • 146.
    Alfredsson, Linda
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Personal och arbetsliv.
    Lissollas, Lina
    Högskolan Dalarna, Akademin Industri och samhälle, Personal och arbetsliv.
    Attrahera och Behålla Sjuksköterskor: I en Offentlig Verksamhet2014Självständigt arbete på grundnivå (kandidatexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 147.
    Alhamwi, MHD Mouaz
    Högskolan Dalarna, Akademin Industri och samhälle, Energiteknik.
    Evaluating the Economic Feasibility for utilizing PV Power Optimizers in Large-scale PV Plants for The Cases of Soiling, Mismatching, and Degradation2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The solar PV modules are influenced by a variety of loss mechanisms by which the energy yield is affected. A PV system is the sum of individual PV modules which should ideally operate similarly, however, inhomogeneous soiling, mismatching, and degradation, which are the main focus in this study, lead to dissimilarities in PV modules operating behavior and thus, lead to losses which will be assessed intensively in terms of energy yield.

    The dissimilarities in PV modules are referred to the ambient conditions or the PV modules

    characteristics which result in different modules’ maximum power point (MPP) and thus, different currents generated by each PV modules which cause the mismatching. However, the weakest PV module current governs the string current, and the weakest string voltage governs the voltage.

    Power optimizers are electronic devices connected to the PV modules which adjust the voltages of the PV modules in order to obtain the same current as the weakest module and thus, extract

    the modules’ MPP. Hence, the overall performance of the PV plant is enhanced. On the other hand, the power optimizers add additional cost to the plant’s investment cost and thus, the extra energy yield achieved by utilizing the power optimizers must be sufficient to compensate the additional cost of the power optimizers. This is assessed by designing three systems, a reference system with SMA inverters, a system utilizes Tigo power optimizers and SMA inverters, and a system utilizes SolarEdge power optimizers and inverters. The study considers four different locations which are Borlänge, Madrid, Abu Dhabi, and New Delhi.

    An Excel model is created and validated to emulate the inhomogeneous soiling and to evaluate the economic feasibility of the power optimiz

    ers. The model’s inputs are obtained from PVsyst and the precipitation data is obtained from Meteoblue and SMHI database.

    The economic model is based on the relation between Levelized Cost of Electricity (LCOE) which will be used to derive the discount rate. Graphs representing the discounted payback period as a function of the feed-in tariff for different discount rates is created in order to obtain the discounted payback period.

    The amount of extra energy yielded by the Tigo and the SolarEdge systems is dependent on the soiling accumulated on the PV modules. Relative to the reference system, 6.5 % annual energy gain by the systems utilizing the power optimizers in soiling conditions, up to 2.1 % in the degradation conditions, and up to 9.7 % annual energy gain at 10 % mismatching rate. The extra energy yield is dependent on the location, however, the Tigo and the SolarEdge systems have yielded more energy than the reference system in all cases except one case when the mismatch losses is set to zero.

    The precipitation pattern is very influential, and a scare precipitation leads to a reduction in the energy yield, in this case, the Tigo and the SolarEdge systems overall performance is enhanced and the extra energy gain becomes greater.

    The Tigo system yield slightly more energy than the SolarEdge system in most cases,

    however, during the plant’s lifetime, the SolarEdge system could become more efficient than the Tigo system which is referred to the system’s sizing ratio. The degradation of the system or the soiling accumulation decreases the irradiation and thus, a slightly oversized PV array become suitable and deliver an optimal power to the inverters.

    The SolarEdge system is feasible in all scenarios in terms of LCOE and discounted payback period, although its slightly lower performance relative to the Tigo system, this is referred to its low initial cost in comparison to the other systems. The Tigo system is mostly infeasible although it yields more energy than the reference and the SolarEdge systems, this is referred

    iii

    to its relatively high initial cost. However, feed-

    in tariffs higher than 20 € cent / kWh make

    all systems payback within less than 10 years.

    The results have overall uncertainty within ± 6.5 % including PVsyst, Excel model, and the

    precipitation uncertainties. The uncertainty in the degradation and the mismatching

    calculations is limited to PVsyst uncertainty which is ± 5 %. The uncertainties in LCOE in

    the location of New Delhi, since it is the worst-case scenario, are 5.1 % and 4 % for the

    reference and the systems utilizing power optimizers, respectively.

    Consequently, accommodating the uncertainties to the benefits gained by utilizing power

    optimizers indicates that the energy gain would oscillate in the range of 6 % - 6.9 % for the

    soiling calculations, 2 % - 2.2 % for the degradation simulations, and 9.2 % - 10.2 % for the

    mismatching simulations at 10 % mismatchrate.

  • 148.
    Al-Hashimi, Mazin
    Högskolan Dalarna, Akademin Industri och samhälle, Energiteknik.
    Modelling Installation Cost for Rooftop PV Systems2015Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The cost of installation of photovoltaic (PV) systems is a substantial fraction of the total cost of the project and the same is increasing with reducing cost of PV modules. This study essentially deals with the cost of installation of rooftop PV systems and presents a cost model for it, based on data collected for more than 700 projects of different capacities, roof types, circumstances, and locations in Sweden. The presented cost model shall give reasonably accurate estimations about the costs associated with the main elements of the process of rooftop PV systems installation, such as labour, shipping, equipment, travel, and accommodation, for different situations as a function of few important variables such as system capacity, roof type, distance to the installation location, etc. The weighted share of cost of the different elements of the cost model out of the total cost of installation was determined. Several relationships between different elements and variables were examined to find relationships that can help to better understand the process of installation and to develop the cost model. The variations in time required per unit system capacity have been examined for several processes of rooftop PV systems installation, to investigate about potential for reduction in the time and thus the cost due to economies of scale.

  • 149.
    Alhasweh, Mohamed Abdulwahab
    et al.
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    Farid, Babrak
    Högskolan Dalarna, Akademin Industri och samhälle, Företagsekonomi.
    The effects of Ikea and external shopping centers on regional trade and retail growth: A comparative analysis of Ikea’s establishment in Kalmar and Karlstad2010Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This paper examines the effects of Ikea store establishment in Kalmar and Karlstad on the trade and retail inside the two cities, and as well on the trade and retail in the close neighboring municipalities and in further peripheral municipalities in both regions. After the establishment of Ikea store, Kalmar and Karlstad have experienced significant growth in trade and retail. The question, however, is how big this growth is in both cities? And how different locations on different distances from Ikea have been affected? What impact there was on different segments of the retail? How different business branches have been affected? How large the catchment area for the emerging new large-scale retail locations is? These questions, in addition to few others, are investigated in this paper. The thesis starts with an introduction chapter containing a background of the topic, problem description, the investigated questions, the purpose, and the outline of the paper. The next chapter includes the frame of reference which consists of literature review and theoretical framework about the external shopping centers and their impact on retail and regional trade development. It includes also information gathered from previous studies technical reports and other available sources about the subject. The third chapter includes description for the methods used to collect the primary and secondary data needed for the purpose of this study. Then the empirical framework which demonstrates the results of the conducted research followed by analysis and concluded in discussion and conclusion. Mixed methods are used as research strategy in this thesis, and the method to conduct the research is based on telephone interviews for the primary (qualitative) data, and documents and desk research for the secondary (quantitative) data. The gathered data is analyzed and designed in a way that allows the usage of comparative analysis technique to present the findings and draw conclusions. The results showed that new established Ikea retail store outside the city boundaries results with many effects on the city center and on the neighboring municipalities as well. The city center seems not to be affected negatively, but on the contrary positive effects were witnessed in both regions, these positive effects are linked to the increase inflow of customers from the external retail area which is known as spillover effect. III On the other hand, the neighboring towns and municipalities are more negatively affected especially with the trade of con-convenience goods as the consumers in these towns and municipalities start to go to the area of Ikea and the large external retail center to do their purchasing, the substitution effect is then said to be occurred. Moreover, the further far municipalities do not seem to be significantly affected by the establishment of Ikea. These effects whether positive or negative could be monitored by looking to few trade parameters such as the turnover, the sales index, and the consumers’ expenditure, these parameters can be very useful to measure the developments and changes in the trade and retail in a given place. 

  • 150.
    Ali, Liaqut
    et al.
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    Avdic, Anders
    Högskolan Dalarna, Akademin Industri och samhälle, Informatik.
    A framework for ICT-based knowledge sharing in sustainable rural development: the case of Gilgit-Baltistan, Pakistan2015Ingår i: Electronic Journal of Knowledge Management, ISSN 1479-4411, E-ISSN 1479-4411, Vol. 13, nr 2, s. 103-116Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Some 50% of the people in the world live in rural areas, often under harsh conditions and in poverty. The need for knowledge of how to improve living conditions is well documented. In response to this need, new knowledge of how to improve living conditions in rural areas and elsewhere is continuously being developed by researchers and practitioners around the world. People in rural areas, in particular, would certainly benefit from being able to share relevant knowledge with each other, as well as with stakeholders (e.g. researchers) and other organizations (e.g. NGOs). Central to knowledge management is the idea of knowledge sharing. This study is based on the assumption that knowledge management can support sustainable development in rural and remote regions. It aims to present a framework for knowledge management in sustainable rural development, and an inventory of existing frameworks for that. The study is interpretive, with interviews as the primary source for the inventory of stakeholders, knowledge categories and Information and Communications Technology (ICT) infrastructure. For the inventory of frameworks, a literature study was carried out. The result is a categorization of the stakeholders who act as producers and beneficiaries of explicit and indigenous development knowledge. Stakeholders are local government, local population, academia, NGOs, civil society and donor agencies. Furthermore, the study presents a categorization of the development knowledge produced by the stakeholders together with specifications for the existing ICT infrastructure. Rural development categories found are research, funding, agriculture, ICT, gender, institutional development, local infrastructure development, and marketing & enterprise. Finally, a compiled framework is presented, and it is based on ten existing frameworks for rural development that were found in the literature study, and the empirical findings of the Gilgit-Baltistan case. Our proposed framework is divided in four levels where level one consists of the identified stakeholders, level two consists of rural development categories, level three of the knowledge management system and level four of sustainable rural development based on the levels below. In the proposed framework we claim that the sustainability of rural development can be achieved through a knowledge society in which knowledge of the rural development process is shared among all relevant stakeholders.

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