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  • 1.
    Ahmed, Salim Saif Saeed
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Identify the driving behaviour in a parking lot in terms of distance.2018Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    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.

  • 2.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Does Euclidean distance work well when the p-median model is applied in rural areas?2012In: Annals of Operations Research, ISSN 0254-5330, E-ISSN 1572-9338, Vol. 201, no 1, p. 83-97Article in journal (Refereed)
    Abstract [en]

    The p-median model is used to locate P centers to serve a geographically distributed population. A cornerstone of such a model is the measure of distance between a service center and demand points, i.e. the location of the population (customers, pupils, patients, and so on). Evidence supports the current practice of using Euclidean distance. However, we find that the location of multiple hospitals in a rural region of Sweden with anon-symmetrically distributed population is quite sensitive to distance measure, and somewhat sensitive to spatial aggregation of demand points.

  • 3.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Methodological issues in applying Location Models to Rural areas2010Report (Other academic)
    Abstract [en]

    Location Models are usedfor planning the location of multiple service centers in order to serve a geographicallydistributed population. A cornerstone of such models is the measure of distancebetween the service center and a set of demand points, viz, the location of thepopulation (customers, pupils, patients and so on). Theoretical as well asempirical evidence support the current practice of using the Euclidian distancein metropolitan areas. In this paper, we argue and provide empirical evidencethat such a measure is misleading once the Location Models are applied to ruralareas with heterogeneous transport networks. This paper stems from the problemof finding an optimal allocation of a pre-specified number of hospitals in alarge Swedish region with a low population density. We conclude that the Euclidianand the network distances based on a homogenous network (equal travel costs inthe whole network) give approximately the same optimums. However networkdistances calculated from a heterogeneous network (different travel costs indifferent parts of the network) give widely different optimums when the numberof hospitals increases.  In terms ofaccessibility we find that the recent closure of hospitals and the in-optimallocation of the remaining ones has increased the average travel distance by 75%for the population. Finally, aggregation the population misplaces the hospitalsby on average 10 km.

  • 4.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Information Systems. Dalarna University, School of Technology and Business Studies, Human Geography.
    Var ska sjukhusen ligga?2013In: Ekonomiska samfundets tidskrift, ISSN 0013-3183, E-ISSN 2323-1378, no 3, p. 165-171Article in journal (Refereed)
    Abstract [sv]

    Denna artikel visar på en metod för att undersöka hur optimal befolkningens fysiska tillgänglighet till sjukvården är. Detta är relevant med tanke på den svenska storregionala omdaningen som säkerligen kommer provocera fram omprövningar av sjukhusens framtida placering.

    Med Dalarna som exempel fann vi att en ökning från dagens två till tre optimalt lokaliserade sjukhus skulle minska befolkningens genomsnittliga reseavstånd med 25 %.

    På basis av transportsektorns standardkalkyler för samhällsekonomisk effekter vid resande, samt av kostnader för drift av sjukvård sluter vi dessutom oss till att en komplettering av nuvarande två sjukhus i Dalarna med ett tredje vore samhällsekonomiskt effektivt.

  • 5.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    An empirical test of the gravity p-median model2012Report (Other academic)
    Abstract [en]

    A customer is presumed to gravitate to a facility by the distance to it and the attractiveness of it. However regarding the location of the facility, the presumption is that the customer opts for the shortest route to the nearest facility.This paradox was recently solved by the introduction of the gravity p-median model. The model is yet to be implemented and tested empirically. We implemented the model in an empirical problem of locating locksmiths, vehicle inspections, and retail stores ofv ehicle spare-parts, and we compared the solutions with those of the p-median model. We found the gravity p-median model to be of limited use for the problem of locating facilities as it either gives solutions similar to the p-median model, or it gives unstable solutions due to a non-concave objective function.

  • 6.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Distance measure and the p-median problem in rural areas2012Report (Other academic)
    Abstract [en]

    The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population patronize the nearest facility and that the distance between the resident and the facility may be measured by the Euclidean distance. Carling, Han, and Håkansson (2012) compared two network distances with the Euclidean in a rural region witha sparse, heterogeneous network and a non-symmetric distribution of thepopulation. For a coarse network and P small, they found, in contrast to the literature, the Euclidean distance to be problematic. In this paper we extend their work by use of a refined network and study systematically the case when P is of varying size (2-100 facilities). We find that the network distance give as gooda solution as the travel-time network. The Euclidean distance gives solutions some 2-7 per cent worse than the network distances, and the solutions deteriorate with increasing P. Our conclusions extend to intra-urban location problems.

  • 7.
    Carling, Kenneth
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Short Communication: A compelling argument for the gravity p-median model2012Report (Other academic)
    Abstract [en]

    The p-median model is used to locate P facilities to serve a geographically distributed population. Conventionally, it is assumed that the population always travels to the nearest facility. Drezner and Drezner (2006, 2007) provide three arguments on why this assumption might be incorrect, and they introduce the extended the gravity p-median model to relax the assumption. We favour the gravity p-median model, but we note that in an applied setting, Drezner and Drezner’s arguments are incomplete. In this communication, we point at the existence of a fourth compelling argument for the gravity p-median model.

  • 8.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Something old, something new, something borrowed, something blue part 1: Alan turing, hypercomputation, adam smith and next generation intelligent systems2012In: Journal of Intelligent Systems, ISSN 0334-1860, Vol. 21, no 4, p. 325-330Article in journal (Refereed)
    Abstract [en]

    In this article intelligent systems are placed in the context of accelerated Turing machines. Although such machines are not currently a reality, the very real gains in computing power made over previous decades require us to continually reevaluate the potential of intelligent systems. The economic theories of Adam Smith provide us with a useful insight into this question. © de Gruyter 2012.

  • 9.
    Kogo, Gloria
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Analyzing automatic cow recordings to detect the presence of outliers in feed intake data recorded from dairy cows in Lovsta farm2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Outliers are a major concern in data quality as it limits the reliability of any data. The

    objective of our investigation was to examine the presence and cause of outliers in the system

    for controlling and recording the feed intake of dairy cows in Lovsta farm, Uppsala Sweden.

    The analyses were made on data recorded as a timestamp of each visit of the cows to

    the feeding troughs from the period of August 2015 to January 2016. A three step

    methodology was applied to this data. The first step was fitting a mixed model to the

    data then the resulting residuals was used in the second step to fit a model based

    clustering for Gaussian mixture distribution which resulted in clusters of which 2.5% of

    the observations were in the outlier cluster. Finally, as the third step, a logistic

    regression was then fit modelling the presence of outliers versus the non-outlier

    clusters. It appeared that on early hours of the morning between 6am to 11.59am, there

    is a high possibility of recorded values to be outliers with odds ratio of 1.1227 and this

    is also the same time frame noted to have the least activity in feed consumption of the

    cows with a decrease of 0.027 kilograms as compared to the other timeframes. These

    findings provide a basis for further investigation to more specifically narrow down the

    causes of the outliers.

  • 10.
    Laryea, Rueben
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    A data-driven decision support system for coherency of experts’ judgment in complex classification problems: The case of food security as a UN sustainable development goal2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Everyday humans need to make individual or collective decisions. Often the decisions aim at achieving multiple goals (thus involving multiple criteria) and rely on the decision maker(s)’ intuition, internal data, as well as external sources of data. Faced with a complex decision problem of this kind, it is a great challenge to decisionmakers to be logically coherent over time with regard to their preferences. To aid in achieving coherency, operation researchers and decision analysts have developed formal methods to support decision makers. One such method is the UTADIS method that serves as the workhorse for this thesis. I received the request from UN officials who had to manage the sustainable development goals while addressing the issue of food security. They wished for a decision support system (DSS) that could aid in their classification of countries to mitigate the risk of failing on food security. The virtue of the DSS should be that their expert judgment was complemented by formal methods for better risk classification. The UTADIS method was fitting for the purpose, but it lacked implementability. In particular, it required an iterative approach engaging the experts multiple times, while not readily lending itself to making use of external data, making it inefficient as a DSS. The fundamental contribution of this thesis is that I have solved these shortcomings of the UTADIS method, such that it now readily can be used in a functionally efficient way for the desired purpose of the UN. In solving these problems, it is also more broadly implementable as a DSS, as I have validated the artifact to a DSS, by use of several demonstrations and exposed it to sensitivity analysis.

  • 11.
    Laryea, Rueben
    Stockholm University.
    Project outcome classification with imprecise criteria information2013In: International Journal of Applied Decision Sciences, ISSN 1755-8077, E-ISSN 1755-8085, Vol. 6, no 4Article in journal (Refereed)
    Abstract [en]

    A case in which managers have to make project outcome classification decisions with uncertainty in independently related criteria values is considered in this paper. A multi-criteria decision model is developed in this paper by selecting methods which delved into data analysis to help managers make informed classification decisions. Uncertainty in the criteria values is resolved using linear programming which enables managers to know the profit outcome of their projects for efficient resource allocation. The classification scheme from the linear programming process is used as predefined classification inputs for use in the UTilités Additives DIScriminantes (UTADIS) method, which further produces a classification model. The analysis presented a no misclassification error in the predefined classifications from the linear programming and the classifications in the UTADIS method thus further boosting the confidence managers can entrust in the resulting classification model.

  • 12.
    Laryea, Rueben
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Farsari, Ioanna
    Dalarna University, School of Technology and Business Studies, Tourism Studies.
    Nyberg, Roger G.
    Dalarna University, School of Technology and Business Studies, Information Systems.
    A Decision Tool Approach to Sensitivity Analysis in a Risk Classification Model2018In: Article in journal (Refereed)
    Abstract [en]

    A Decision Analytical tool capable of handling numerically imprecise data for decision making is used in this paper to analyze the risk of the effect of data alteration in the ranking positions of country alternatives for food price volatility. Unguided decision making processes would lead to non-optimal decisions with it’s dire consequences on the resources of organizations. The paper is thus guided by the use of an accurate risk classification model to implement uncertainty and imprecision which are essential part of real life decision making processes with computer based tools to overcome the problem of possibilities uncertain and imprecise input data of criteria and alternatives. A ranking of the alternatives is conducted after imprecision is considered in the input data and a further analysis is carried out to determine which criteria is sensitive enough to alter the position of a country in the rankings.

  • 13.
    Niskanen,, Tom
    et al.
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Nyström, Johan
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Ensidesapplikationers kodkvalitet och förvaltningsbarhet: En jämförelse av förvaltningsbarhet hos single-page applications utvecklade med AngularJS och React2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Single-page applications have historically been subject to strong market forces driving fast development and deployment in lieu of quality control and changeable code, which are important factors for maintainability. In this report we develop two functionally equivalent applications using AngularJS and React and compare their maintainability as defined by ISO/IEC 9126. AngularJS and React represent two distinct approaches to web development, with AngularJS being a general framework providing rich base functionality and React a small specialized library for efficient view rendering. The quality comparison was accomplished by calculating Maintainability Index for each application. Version control analysis was used to determine quality indicators during development and subsequent maintenance where new functionality was added in two steps.

    The results show no major differences in maintainability in the initial applications. As more functionality is added the Maintainability Index decreases faster in the AngularJS application, indicating a steeper increase in complexity compared to the React application. Source code analysis reveals that changes in data flow requires significantly larger modifications of the AngularJS application due to its inherent architecture for data flow. We conclude that frameworks are useful when they facilitate development of known requirements but less so when applications and systems grow in size.

    Sammanfattning: Ensidesapplikationer har historiskt sett påverkats av starka marknadskrafter som pådriver snabba utvecklingscykler och leveranser. Detta medför att kvalitetskontroll och förändringsbar kod, som är viktiga faktorer för förvaltningsbarhet, blir lidande. I denna rapport utvecklar vi två funktionellt ekvi-valenta ensidesapplikationer med AngularJS och React samt jämför dessa applikationers förvaltningsbarhet enligt ISO/IEC 9126. AngularJS och React representerar två distinkta angreppsätt på webbutveckling, där AngularJS är ett ramverk med mycket färdig funktionalitet och React ett mindre bibliotek specialiserat på vyrendering. Kvalitetsjämförelsen utfördes genom att beräkna förvaltningsbarhetsindex för respektive applikation. Versionshanteringsanalys användes för att bestämma andra kvalitetsindikatorer efter den initiala utvecklingen samt två efterföljande underhållsarbeten.

    Resultaten visar inga markanta skillnader i förvaltningsbarhet för de initiala applikationerna. I takt med att mer funktionalitet lades till sjönk förvaltnings-barhetsindex snabbare för AngularJS-applikationen, vilket motsvarar en kraftigare ökning i komplexitet jämfört med React-applikationen. Versionshanteringsanalys visar att ändringar i dataflödet kräver större modifikationer för AngularJS-applikationen på grund av dess förbestämda arkitektur. Utifrån detta drar vi slutsatsen att ramverk är användbara när de understödjer utvecklingen mot kända krav men att deras nytta blir begränsad ju mer en applikation växer i storlek.

  • 14.
    Schiavella, Mauro
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Pelagatti, Matteo
    University Milano-Bicocca.
    Lepore, Gabriele
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    PokerMapper: mapping executive functions, poker playing ability and responsible gambling in online environments2015Conference paper (Refereed)
    Abstract [en]

    Research objectives

    Poker and responsible gambling both entail the use of the executive functions (EF), which are higher-level cognitive abilities. The main objective of this work was to assess if online poker players of different ability show different performances in their EF and if so, which functions are the most discriminating ones. The secondary objective was to assess if the EF performance can predict the quality of gambling, according to the Gambling Related Cognition Scale (GRCS), the South Oaks Gambling Screen (SOGS) and the Problem Gambling Severity Index (PGSI).

    Sample and methods

    The study design consisted of two stages: 46 Italian active players (41m, 5f; age 32±7,1ys; education 14,8±3ys) fulfilled the PGSI in a secure IT web system and uploaded their own hand history files, which were anonymized and then evaluated by two poker experts. 36 of these players (31m, 5f; age 33±7,3ys; education 15±3ys) accepted to take part in the second stage: the administration of an extensive neuropsychological test battery by a blinded trained professional. To answer the main research question we collected all final and intermediate scores of the EF tests on each player together with the scoring on the playing ability. To answer the secondary research question, we referred to GRCS, PGSI and SOGS scores.  We determined which variables that are good predictors of the playing ability score using statistical techniques able to deal with many regressors and few observations (LASSO, best subset algorithms and CART). In this context information criteria and cross-validation errors play a key role for the selection of the relevant regressors, while significance testing and goodness-of-fit measures can lead to wrong conclusions.

     

    Preliminary findings

    We found significant predictors of the poker ability score in various tests. In particular, there are good predictors 1) in some Wisconsin Card Sorting Test items that measure flexibility in choosing strategy of problem-solving, strategic planning, modulating impulsive responding, goal setting and self-monitoring, 2) in those Cognitive Estimates Test variables related to deductive reasoning, problem solving, development of an appropriate strategy and self-monitoring, 3) in the Emotional Quotient Inventory Short (EQ-i:S) Stress Management score, composed by the Stress Tolerance and Impulse Control scores, and in the Interpersonal score (Empathy, Social Responsibility, Interpersonal Relationship). As for the quality of gambling, some EQ-i:S scales scores provide the best predictors: General Mood for the PGSI; Intrapersonal (Self-Regard; Emotional Self-Awareness, Assertiveness, Independence, Self-Actualization) and Adaptability  (Reality Testing, Flexibility, Problem Solving) for the SOGS, Adaptability for the GRCS.

    Implications for the field

    Through PokerMapper we gathered knowledge and evaluated the feasibility of the construction of short tasks/card games in online poker environments for profiling users’ executive functions. These card games will be part of an IT system able to dynamically profile EF and provide players with a feedback on their expected performance and ability to gamble responsibly in that particular moment. The implementation of such system in existing gambling platforms could lead to an effective proactive tool for supporting responsible gambling. 

  • 15.
    Schiavella, Mauro
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Pelagatti, Matteo
    University Milano-Bicocca.
    Lepore, Gabriele
    Sisal Poker.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Cherubini, Paolo
    University Milano-Bicocca.
    PokerMapper: Final report2015Report (Other academic)
  • 16. Schiavella, Mauro
    et al.
    Pelagatti, Matteo
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Lepore, Gabriele
    Cherubini, Paolo
    Profiling online poker players: Are executive functions correlated with poker ability and problem gambling?2018In: Journal of Gambling Studies, ISSN 1050-5350, E-ISSN 1573-3602, Vol. 34, no 3, p. 823-851Article in journal (Refereed)
    Abstract [en]

    Poker playing and responsible gambling both entail the use of the executive functions (EF), which are higher-level cognitive abilities. This study investigated if online poker players of different ability showed different performances in their EF and if so, which functions were the most discriminating for their playing ability. Furthermore, it assessed if the EF performance was correlated to the quality of gambling, according to self-reported questionnaires (PGSI, SOGS, GRCS). Three poker experts evaluated anonymized poker hand history files and, then, a trained professional administered an extensive neuropsychological test battery. Data analysis determined which variables of the tests correlated with poker ability and gambling quality scores. The highest correlations between EF test results and poker ability and between EF test results and gambling quality assessment showed that mostly different clusters of executive functions characterize the profile of the strong(er) poker player and those ones of the problem gamblers (PGSI and SOGS) and the one of the cognitions related to gambling (GRCS). Taking into consideration only the variables overlapping between PGSI and SOGS, we found some key predictive factors for a more risky and harmful online poker playing: a lower performance in the emotional intelligence competences (Emotional Quotient inventory Short) and, in particular, those grouped in the Intrapersonal scale (emotional self-awareness, assertiveness, self-regard, independence and self-actualization).

  • 17.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Bergquist, Filip
    Senek, Marina
    Nyholm, Dag
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Individual levodopa dosing suggestions based on a single dose test2016Conference paper (Other academic)
  • 18.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Slutrapport PAULINA2015Report (Other academic)
1 - 18 of 18
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