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  • 251. Rahman, Asif
    et al.
    Yella, Siril
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Simulation and optimisation techniques for sawmill yard operation: A literature review2014In: Journal of Intelligent Learning Systems and Applications, ISSN 2150-8410, Vol. 6, no 1, p. 21-34Article in journal (Refereed)
    Abstract [en]

    Increasing costs and competitive business strategies are pushing sawmill enterprises to make an effort for optimization of their process management. Organizational decisions mainly concentrate on performance and reduction of operational costs in order to maintain profit margins. Although many efforts have been made, effective utilization of resources, optimal planning and maximum productivity in sawmill are still challenging to sawmill industries. Many researchers proposed the simulation models in combination with optimization techniques to address problems of integrated logistics optimization. The combination of simulation and optimization technique identifies the optimal strategy by simulating all complex behaviours of the system under consideration including objectives and constraints. During the past decade, an enormous number of studies were conducted to simulate operational inefficiencies in order to find optimal solutions. This paper gives a review on recent developments and challenges associated with simulation and optimization techniques. It was believed that the review would provide a perfect ground to the authors in pursuing further work in optimizing sawmill yard operations.

  • 252.
    Rahman, Junaedur
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Motion Detection for Video Surveillance2008Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    This thesis is related to the broad subject of automatic motion detection and analysis in video surveillance image sequence. Besides, proposing the new unique solution, some of the previous algorithms are evaluated, where some of the approaches are noticeably complementary sometimes. In real time surveillance, detecting and tracking multiple objects and monitoring their activities in both outdoor and indoor environment are challenging task for the video surveillance system. In presence of a good number of real time problems limits scope for this work since the beginning. The problems are namely, illumination changes, moving background and shadow detection. An improved background subtraction method has been followed by foreground segmentation, data evaluation, shadow detection in the scene and finally the motion detection method. The algorithm is applied on to a number of practical problems to observe whether it leads us to the expected solution. Several experiments are done under different challenging problem environment. Test result shows that under most of the problematic environment, the proposed algorithm shows the better quality result.

  • 253.
    Rahman, Mostafizur
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Branch and Bound Algorithm for Multiprocessor Scheduling2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The multiprocessor task graph scheduling problem has been extensively studied as academic optimization problem which occurs in optimizing the execution time of parallel algorithm with parallel computer. The problem is already being known as one of the NPhard problems. There are many good approaches made with many optimizing algorithm to find out the optimum solution for this problem with less computational time. One of them is branch and bound algorithm. In this paper, we propose a branch and bound algorithm for the multiprocessor scheduling problem. We investigate the algorithm by comparing two different lower bounds with their computational costs and the size of the pruned tree. Several experiments are made with small set of problems and results are compared in different sections.

  • 254.
    Ramsell, Emanuel
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Undersöka möjligheten att köra Microsoft .NET program på webbserver2006Independent thesis Basic level (degree of Bachelor)Student thesis
  • 255.
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    A dispatching tool for railway Transportation2006In: PATAT 06, BRNO, 2006Conference paper (Other academic)
    Abstract [en]

    Railway transportations becomes again to be seen as an efficient and environmentally friendly mean of transportation. To develop it, users (both passengers and compagnies) want to have reliability and especially trains which follow timetables. If to reduce causes leading to delay or cancel a train is a difficult task, we may put some effort to minimize consequences of this problem to other tra ins. This chain effect tends to be worse and worse since the traffic is increasing while the infrastructure remains almost the same for ecomomical reasons. Train Dispatching (i.e to route train in real-time) is an important key to reduce delays and other effects in case of problems. The dispatcher chooses for each train on which track it should run and can ask a rain to stop. A typical example is the single-track connection where only in few places trains in opposite directions can meet. If the preliminary schedule is built in order to have crossing done without let some trains waiting for the other, the dispatcher should in case of an unexpected delay of one train choose either to move the crossing to another place or to stop the on-time train and keep the crossin g at the same place. When the network consists of dual or several tracks, the main problem is not the crossing but the difference in speed of different t rains (freight, long-distance passengers, suburban) and where and how a train can overtake another one.

  • 256.
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    DisTrain: a simulation tool for train dispatching2005In: Proceedings 2005 IEEE Intelligent Transportation Systems Conference (ITSC), Vienna, Austria: IEEE , 2005Conference paper (Refereed)
    Abstract [en]

    This paper introduces main motivations and ideas of the tool called DisTrain whioch is an on-going work. The purpose of thistool is to provide a library to work and solve the Train Dispatching (or re-scheduling) problem. This paper is organized as follow: The first section introduce the briefly the problem and give a small litterature survey around this problem. The second section describes the main motivations and goals of this tool. Section III explain how the problem is represented and the interface between data and the library. Section IV explain how the library works and explain how different algorithms can solve this problem and why they should be tried. The fifth section targets practical issues. Then, section VI, VII conclude this paper and point out the future of DisTrain. This paper describes an on-going research work on the train dispatching problem. This dispatching or re-scheduling problem (which is NP-complete in general cases) lacks a benchmark or a library to test different algorithms. Therefore, we present a modelisation of the problem, on which our future tool is based. The tool is decomposed into a simulation engine (event driven) which may use different algorithms to solve the problem. Different algorithms may be used and tried

  • 257.
    Rebreyend, Pascal
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Clugery, Cedric
    Hily, Emmanuel
    A Heuristic-Based Bee Colonyt Algorthm for the Multiprocessor Scheduling Problem2010In: Nature Inspired Cooperative Strategies for Optimization (NICSO 2010), Heidelberg: Springer Berlin , 2010, Vol. 284, p. 295-304Chapter in book (Other academic)
    Abstract [en]

    The multiprocessor scheduling is one of the NP-complete scheduling problems. This problem comes when a known parallel program must be executed on a parallel computer. Different methods and algorithms have been tested for this scheduling problem. This paper presents and tests a hybrid bee algorithm. In this approach, the bee algorithm is combined with a heuristic in order to produce quickly good solutions. The choosen heuristic is a greedy approach and hybridization is done using the indirect representation. The heuristic is a list heuristic and the bee algorithm has to find the best order for the ordered list of tasks used by the heuristic. Experimental results on different benchmarks will be presented and analized, as well as a comparison with other hybrid approaches.

  • 258.
    Rebreyend, Pascal
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Yella, Siril
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    International Master Programme: two intakes per year for a better peer group support2005In: LMD Informatique en Europe et Emploi, Montpellier, France, 2005Conference paper (Other academic)
  • 259.
    Rebreyend, Pascal
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Statistics.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Human Geography.
    How does different algorithm work when applied on the different road networks when optimal location of facilities is searched for in rural areas?2014In: Web Information Systems Engineering – WISE 2013 Workshops: WISE 2013 International Workshops BigWebData, MBC, PCS, STeH, QUAT, SCEH, and STSC 2013, Nanjing, China, October 13-15, 2013, Revised Selected Papers / [ed] Zhisheng Huang, Chengfei Liu, Jing He, Guangyan Huang, Berlin: Springer Berlin/Heidelberg, 2014, Vol. 8182, p. 284-291Conference paper (Refereed)
    Abstract [en]

    The p-median problem is often used to locate P service facilities in a geographically distributed population. Important for the performance of such a model is the distance measure. The first aim in this study is to analyze how the optimal location solutions vary, using the p-median model, when the road network is alternated. It is hard to find an exact optimal solution for p-median problems. Therefore, in this study two heuristic solutions are applied, simulating annealing and a classic heuristic. The secondary aim is to compare the optimal location solutions using different algorithms for large p-median problem. The investigation is conducted by the means of a case study in a rural region with a. asymmetrically distributed population, Dalecarlia. The study shows that the use of more accurate road networks gives better solutions for optimal location, regardless what algorithm that is used and regardless how many service facilities that is opt for. It is also shown that the Simulating annealing algorithm not just is much faster than the classic heuristic used here, but also in most cases gives better solutions.

  • 260.
    Rebreyend, Pascal
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Lemarchand, Laurent
    Euler, Reinhardt
    A computational comparison of different algorithms for very large p-median problems2015In: Evolutionary Computation in Combinatorial Optimization: 15th European Conference, EvoCOP 2015, Copenhagen, Denmark, April 8-10, 2015, Proceedings / [ed] Gabriela Ochoa, Francisco Chicano, Springer, 2015, Vol. 9026, p. 13-24Conference paper (Refereed)
    Abstract [en]

    In this paper, we propose a new method for solving large scale p-median problem instances based on real data. We compare different approaches in terms of runtime, memory footprint and quality of solutions obtained. In order to test the different methods on real data, we introduce a new benchmark for the p-median problem based on real Swedish data. Because of the size of the problem addressed, up to 1938 candidate nodes, a number of algorithms, both exact and heuristic, are considered. We also propose an improved hybrid version of a genetic algorithm called impGA. Experiments show that impGA behaves as well as other methods for the standard set of medium-size problems taken from Beasley’s benchmark, but produces comparatively good results in terms of quality, runtime and memory footprint on our specific benchmark based on real Swedish data.

  • 261.
    Rebreyend, Pascal
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Lemarchand, Laurent
    Massé, Damien
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Multiobjective Optimization for Multimode Transportation Problems2018In: Advances in Operations Research, ISSN 1687-9147, E-ISSN 1687-9155, article id 8720643Article in journal (Refereed)
    Abstract [en]

    We propose modelling for a facilities localization problem in the context of multimode transportation. The applicative goal is to locate service facilities such as schools or hospitals while optimizing the different transportation modes to these facilities. We formalize the School Problem and solve it first exactly using an adapted -constraint multiobjective method. Because of the size of the instances considered, we have also explored the use of heuristic methods based on evolutionary multiobjective frameworks, namely, NSGA2 and a modified version of PAES. Those methods are mixed with an original local search technique to provide better results. Numerical comparisons of solutions sets quality are made using the hypervolume metric. Based on the results for test-cases that can be solved exactly, efficient implementation for PAES and NSGA2 allows execution times comparison for large instances. Results show good performances for the heuristic approaches as compared to the exact algorithm for small test-cases. Approximate methods present a scalable behavior on largest problem instances. A master/slave parallelization scheme also helps to reduce execution times significantly for the modified PAES approach.

  • 262.
    Rindberg, Jonas
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Kartdataimport för fälttillämpning2006Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    I dagsläget kan WM-datas Fältmodul i deras MoveITS-system inte hantera kartdata i andra format än Shape. Fältmodulen är en TabletPC som kör operativsystemet Windows XP. Den kan användas för att redigera viss geografisk information som exempelvis skyltpositioner. Fältmodulen används av Stockholms Tekniska kontor för inventering av skyltstolpar. Stockholms Tekniska kontor ska börja leverera sina kartor i GML (Geography Markup Language). Men eftersom WM-datas Fältmodul inte klarar av det formatet skulle det här examensarbetet gå ut på att ta fram komponenter för hantering av det. Då det under examensarbetets gång har varit svårt att få tag i information runt GML har istället en större fokus blivit lagd på MIF (MapInfo Interchange Format). Eftersom det finns andra kommuner som använder MIF finns det intresse från WM-data att det tas fram komponenter även för detta format. Ett stort antal klasser har utvecklats för hantering av MIF-filer. Dessa klasser är helt utvecklade i C# och har gjorts under examensarbetets gång utifrån de specifikationer som finns för formatet från företaget MapInfo. För GML har det tagits fram information som kan ligga till grund för utveckling av komponenter för hantering av det formatet.

  • 263.
    Rönnegård, Lars
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Statistics.
    Vinterkonferens i rumslig statistik i Dalarna2011In: Qvintensen, ISSN 2000-1819, Vol. 2011, no 4Article in journal (Other academic)
  • 264.
    Sadikov, Aleksander
    et al.
    University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, Slovenia.
    Groznik, Vida
    University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, Slovenia.
    Možina, Martin
    University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, Slovenia.
    Žabkar, Jure
    University of Ljubljana, Faculty of Computer and Information Science, Večna pot 113, Ljubljana, Slovenia.
    Nyholm, Dag
    Department of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering. Informatics, School of Business, Örebro University, Örebro, Sweden.
    Georgiev, Dejan
    Ljubljana University Medical Centre, Department of Neurology, Zaloška 2, Ljubljana, Slovenia.
    Feasibility of spirography features for objective assessment of motor function in Parkinson's disease2017In: Artificial Intelligence in Medicine, ISSN 0933-3657, E-ISSN 1873-2860, Vol. 81, no SI, p. 54-62Article in journal (Refereed)
    Abstract [en]

    Objective

    Parkinson's disease (PD) is currently incurable, however proper treatment can ease the symptoms and significantly improve the quality of life of patients. Since PD is a chronic disease, its efficient monitoring and management is very important. The objective of this paper was to investigate the feasibility of using the features and methodology of a spirography application, originally designed to detect early Parkinson's disease (PD) motoric symptoms, for automatically assessing motor symptoms of advanced PD patients experiencing motor fluctuations. More specifically, the aim was to objectively assess motor symptoms related to bradykinesias (slowness of movements occurring as a result of under-medication) and dyskinesias (involuntary movements occurring as a result of over-medication).

    Materials and methods

    This work combined spirography data and clinical assessments from a longitudinal clinical study in Sweden with the features and pre-processing methodology of a Slovenian spirography application. The study involved 65 advanced PD patients and over 30,000 spiral-drawing measurements over the course of three years. Machine learning methods were used to learn to predict the “cause” (bradykinesia or dyskinesia) of upper limb motor dysfunctions as assessed by a clinician who observed animated spirals in a web interface. The classification model was also tested for comprehensibility. For this purpose a visualisation technique was used to present visual clues to clinicians as to which parts of the spiral drawing (or its animation) are important for the given classification.

    Results

    Using the machine learning methods with feature descriptions and pre-processing from the Slovenian application resulted in 86% classification accuracy and over 0.90 AUC. The clinicians also rated the computer's visual explanations of its classifications as at least meaningful if not necessarily helpful in over 90% of the cases.

    Conclusions

    The relatively high classication accuracy and AUC demonstrates the usefulness of this approach for objective monitoring of PD patients. The positive evaluation of computer's explanations suggests the potential use of this methodology in a decision support setting.

  • 265.
    Sadikov, Aleksander
    et al.
    Faculty of Computer and Information Science, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia .
    Žabkar, Jure
    Faculty of Computer and Information Science, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia .
    Možina, Martin
    Faculty of Computer and Information Science, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia .
    Groznik, Vida
    Faculty of Computer and Information Science, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia .
    Nyholm, Dag
    Dept. of Neuroscience, Neurology, Uppsala University, Uppsala, Sweden.
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Feasibility of spirography features for objective assessment of motor symptoms in Parkinson's disease2015In: Artificial Intelligence in Medicine: 15th Conference on Artificial Intelligence in Medicine, AIME 2015, Pavia, Italy, June 17-20, 2015. Proceedings / [ed] John Holmes, Riccardo Bellazzi, Lucia Sacchi and Niels Peek, Springer, 2015, Vol. 9105, p. 267-276Conference paper (Refereed)
    Abstract [en]

    Parkinsons disease (PD) is currently incurable, however the proper treatment can ease the symptoms and significantly improve the quality of patients life. Since PD is a chronic disease, its efficient monitoring and management is very important. The objective of this paper is to investigate the feasibility of using the features and methodology of a spirography device, originally designed to measure early Parkinsons disease (PD) symptoms, for assessing motor symptoms of advanced PD patients suffering from motor fluctuations. More specifically, the aim is to objectively assess motor symptoms related to bradykinesias (slowness of movements occurring as a result of under-medication) and dyskinesias (involuntary movements occurring as a result of over-medication). The work combines spirography data and clinical assessments from a longitudinal clinical study in Sweden with the features and pre-processing methodology of a Slovenian spirography application. The target outcome was to learn to predict the “cause” of upper limb motor dysfunctions as assessed by a clinician who observed animated spirals in a web interface. Using the machine learning methods with feature descriptions from the Slovenian application resulted in 86% classification accuracy and over 90% AUC, demonstrating the usefulness of this approach for objective monitoring of PD patients.

  • 266.
    Saeed, Muhammad
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Production and Delivery (Optimization of production system and reliability)2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    This thesis is done to solve two issues for Sayid Paper Mill Ltd Pakistan. Section one deals with a practical problem arise in SPM that is cutting a given set of raw paper rolls of known length and width, and a set of product paper rolls of known length (equal to the length of raw paper rolls) and width, practical cutting constraints on a single cutting machine, according to demand orders for all customers. To solve this problem requires to determine an optimal cutting schedule to maximize the overall cutting process profitability while satisfying all demands and cutting constraints. The aim of this part of thesis is to develop a mathematical model which solves this problem. Second section deals with a problem of delivering final product from warehouse to different destinations by finding shortest paths. It is an operational routing problem to decide the daily routes for sending trucks to different destination to deliver their final product. This industrial problem is difficult and includes aspect such as delivery to a single destination and multiple destinations with limited resources. The aim of this part of thesis is to develop a process which helps finding shortest path.

  • 267.
    Sajjad Pasha, Mohammad
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Machine vision for automating visual inspection of wooden railway sleepers2007Independent thesis Advanced level (degree of Master (Two Years))Student thesis
  • 268.
    Sanusi, Afeez Ayinla
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Train Dispatching: Heuristic Optimization2006Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Train dispatchers faces lots of challenges due to conflicts which causes delays of trains as a result of solving possible dispatching problems the network faces. The major challenge is for the train dispatchers to make the right decision and have reliable, cost effective and much more faster approaches needed to solve dispatching problems. This thesis work provides detail information on the implementation of different heuristic algorithms for train dispatchers in solving train dispatching problems. The library data files used are in xml file format and deals with both single and double tracks between main stations. The main objective of this work is to build different heuristic algorithms to solve unexpected delays faced by train dispatchers and to help in making right decisions on steps to take to have reliable and cost effective solution to the problems. These heuristics algorithms proposed were able to help dispatchers in making right decisions when solving train dispatching problems.

  • 269.
    Saqlain, Murshid
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Brandt, Daniel
    Dalarna University, School of Technology and Business Studies, Human Geography.
    Rönnegård, Lars
    Dalarna University, School of Technology and Business Studies, Statistics.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Stochastic differential equations modelling of levodopa concentration in patients with Parkinson's disease2018Conference paper (Other academic)
    Abstract [en]

    The purpose of this study is to investigate a pharmacokinetic model of levodopa concentration in patients with Parkinson's disease by introducing stochasticity so that inter-individual variability may be separated into measurement and system noise. It also aims to investigate whether the stochastic differential equations (SDE) model provide better fits than its ordinary differential equations (ODE) counterpart, by using a real data set. Westin et al. developed a pharmacokinetic-pharmacodynamic model for duodenal levodopa infusion described by four ODEs, the first three of which define the pharmacokinetic model. In this study, system noise variables are added to the aforementioned first three equations through a standard Wiener process, also known as Brownian motion. The R package PSM for mixed-effects models is used on data from previous studies for modelling levodopa concentration and parameter estimation. First, the diffusion scale parameter, σ, and bioavailability are estimated with the SDE model. Second, σ is fixed to integer values between 1 and 5, and bioavailability is estimated. Cross-validation is performed to determine whether the SDE based model explains the observed data better or not by comparingthe average root mean squared errors (RMSE) of predicted levodopa concentration. Both ODE and SDE models estimated bioavailability to be about 88%. The SDE model converged at different values of σ that were signicantly different from zero while estimating bioavailability to be about 88%. The average RMSE for the ODE model wasfound to be 0.2980, and the lowest average RMSE for the SDE model was 0.2748 when σ was xed to 4. Both models estimated similar values for bioavailability, and the non-zero σ estimate implies that the inter-individual variability may be separated. However, the improvement in the predictive performance of the SDE model turned out to be rather small, compared to the ODE model.

  • 270.
    Sawaya, Antonio
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Financial time series analysis: Chaos and neurodynamics approach2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    This work aims at combining the Chaos theory postulates and Artificial Neural Networks classification and predictive capability, in the field of financial time series prediction. Chaos theory, provides valuable qualitative and quantitative tools to decide on the predictability of a chaotic system. Quantitative measurements based on Chaos theory, are used, to decide a-priori whether a time series, or a portion of a time series is predictable, while Chaos theory based qualitative tools are used to provide further observations and analysis on the predictability, in cases where measurements provide negative answers. Phase space reconstruction is achieved by time delay embedding resulting in multiple embedded vectors. The cognitive approach suggested, is inspired by the capability of some chartists to predict the direction of an index by looking at the price time series. Thus, in this work, the calculation of the embedding dimension and the separation, in Takens‘ embedding theorem for phase space reconstruction, is not limited to False Nearest Neighbor, Differential Entropy or other specific method, rather, this work is interested in all embedding dimensions and separations that are regarded as different ways of looking at a time series by different chartists, based on their expectations. Prior to the prediction, the embedded vectors of the phase space are classified with Fuzzy-ART, then, for each class a back propagation Neural Network is trained to predict the last element of each vector, whereas all previous elements of a vector are used as features.

  • 271.
    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. 

  • 272.
    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)
  • 273. 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).

  • 274. Senek, Marina
    et al.
    Aquilonius, Sten-Magnus
    Askmark, Håkan
    Bergquist, Filip
    Constantinescu, Radu
    Ericsson, Anders
    Lycke, Sara
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Nyholm, Dag
    Levodopa/carbidopa microtablets in Parkinson's disease: a study of pharmacokinetics and blinded motor assessment2017In: European Journal of Clinical Pharmacology, ISSN 0031-6970, E-ISSN 1432-1041, Vol. 73, no 5, p. 563-571Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Motor function assessments with rating scales in relation to the pharmacokinetics of levodopa may increase the understanding of how to individualize and fine-tune treatments.

    OBJECTIVES: This study aimed to investigate the pharmacokinetic profiles of levodopa-carbidopa and the motor function following a single-dose microtablet administration in Parkinson's disease.

    METHODS: This was a single-center, open-label, single-dose study in 19 patients experiencing motor fluctuations. Patients received 150% of their individual levodopa equivalent morning dose in levodopa-carbidopa microtablets. Blood samples were collected at pre-specified time points. Patients were video recorded and motor function was assessed with six UPDRS part III motor items, dyskinesia score, and the treatment response scale (TRS), rated by three blinded movement disorder specialists.

    RESULTS: AUC0-4/dose and C max/dose for levodopa was found to be higher in Parkinson's disease patients compared with healthy subjects from a previous study, (p = 0.0008 and p = 0.026, respectively). The mean time to maximum improvement in sum of six UPDRS items score was 78 min (±59) (n = 16), and the mean time to TRS score maximum effect was 54 min (±51) (n = 15). Mean time to onset of dyskinesia was 41 min (±38) (n = 13).

    CONCLUSIONS: In the PD population, following levodopa/carbidopa microtablet administration in fasting state, the Cmax and AUC0-4/dose were found to be higher compared with results from a previous study in young, healthy subjects. A large between subject variability in response and duration of effect was observed, highlighting the importance of a continuous and individual assessment of motor function in order to optimize treatment effect.

  • 275.
    Shah, Syed Fawad Ali
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Intelligent Algorithms for a Hybrid FuelCell/Photovoltaic Standalone System: Simulation Of Hybrid FuelCell/Photovoltaic Standalone System2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Intelligent Algorithm is designed for theusing a Battery source. The main function is to automate the Hybrid System through anintelligent Algorithm so that it takes the decision according to the environmental conditionsfor utilizing the Photovoltaic/Solar Energy and in the absence of this, Fuel Cell energy isused. To enhance the performance of the Fuel Cell and Photovoltaic Cell we used batterybank which acts like a buffer and supply the current continuous to the load.

    To develop the main System whlogic based controller was used. Fuzzy Logic based controller used to develop this system,because they are chosen to be feasible for both controlling the decision process and predictingthe availability of the available energy on the basis of current Photovoltaic and Battery conditions.

    The Intelligent Algorithm is designed to optimize the performance of the system and to selectthe best available energy source(s) in regard of the input parameters. The enhance function of these Intelligent Controller is to predict the use of available energy resources and turn on thatparticular source for efficient energy utilization. A fuzzy controller was chosen to take thedecisions for the efficient energy utilization from the given resources. The fuzzy logic basedcontroller is designed in the Matlab-Simulink environment. Initially, the fuzzy based ruleswere built. Then MATLAB based simulation system was designed and implemented. Thenthis whole proposed model is simulated and tested for the accuracy of design and performanceof the system.

  • 276.
    Shahzada, Adnan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Traffic jam information for mobile devices2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
  • 277.
    Shaik, Asif ur Rahman
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Real time video segmentation for recognising paint marks on bad wooden railway sleepers2008Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Wooden railway sleeper inspections in Sweden are currently performed manually by a human operator; such inspections are based on visual analysis. Machine vision based approach has been done to emulate the visual abilities of human operator to enable automation of the process. Through this process bad sleepers are identified, and a spot is marked on it with specific color (blue in the current case) on the rail so that the maintenance operators are able to identify the spot and replace the sleeper. The motive of this thesis is to help the operators to identify those sleepers which are marked by color (spots), using an “Intelligent Vehicle” which is capable of running on the track. Capturing video while running on the track and segmenting the object of interest (spot) through this vehicle; we can automate this work and minimize the human intuitions. The video acquisition process depends on camera position and source light to obtain fine brightness in acquisition, we have tested 4 different types of combinations (camera position and source light) here to record the video and test the validity of proposed method. A sequence of real time rail frames are extracted from these videos and further processing (depending upon the data acquisition process) is done to identify the spots. After identification of spot each frame is divided in to 9 regions to know the particular region where the spot lies to avoid overlapping with noise, and so on. The proposed method will generate the information regarding in which region the spot lies, based on nine regions in each frame. From the generated results we have made some classification regarding data collection techniques, efficiency, time and speed. In this report, extensive experiments using image sequences from particular camera are reported and the experiments were done using intelligent vehicle as well as test vehicle and the results shows that we have achieved 95% success in identifying the spots when we use video as it is, in other method were we can skip some frames in pre-processing to increase the speed of video but the segmentation results we reduced to 85% and the time was very less compared to previous one. This shows the validity of proposed method in identification of spots lying on wooden railway sleepers where we can compromise between time and efficiency to get the desired result.

  • 278.
    Shaik, Asif ur Rahman
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Vlad, Stefan
    Rebreyend, Pascal
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Yella, Siril
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Multi-agent simulation of sawmill yard operations2012In: ASM-ASC 2012 - Applied Simulation and Modelling - Artificial Intelligence and Soft Computing / [ed] A. Bruzzone, M.H. Hamza, 2012Conference paper (Refereed)
    Abstract [en]

    This paper reports the findings of using multi-agent based simulation model to evaluate the sawmill yard operations within a large privately owned sawmill in Sweden, Bergkvist Insjön AB in the current case. Conventional working routines within sawmill yard threaten the overall efficiency and thereby limit the profit margin of sawmill. Deploying dynamic work routines within the sawmill yard is not readily feasible in real time, so discrete event simulation model has been investigated to be able to report optimal work order depending on the situations. Preliminary investigations indicate that the results achieved by simulation model are promising. It is expected that the results achieved in the current case will support Bergkvist-Insjön AB in making optimal decisions by deploying efficient work order in sawmill yard.

  • 279.
    Shaik, Asif ur Rahman
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Yella, Siril
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Image processing technique to count the number of logs in a timber truck2011In: Signal and Image processing 2011, ACTA Press, 2011Conference paper (Refereed)
    Abstract [en]

    This paper summarises the results of using image processing technique to get information about the load of timber trucks before their arrival using digital images or geo tagged images. Once the images are captured and sent to sawmill by drivers from forest, we can predict their arrival time using geo tagged coordinates, count the number of (timber) logs piled up in a truck, identify their type and calculate their diameter. With this information we can schedule and prioritise the inflow and unloading of trucks in the light of production schedules and raw material stocks available at the sawmill yard. It is important to keep all the actors in a supply chain integrated coordinated, so that optimal working routines can be reached in the sawmill yard.   

  • 280.
    Shaik, Asif ur Rahman
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Yella, Siril
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Simulation model using meta heuristic algorithms for achieving optimal arrangement of storage bins in a sawmill yard2014In: Journal of Intelligent Learning Systems and Applications, ISSN 2150-8402, E-ISSN 2150-8410, Vol. 6, no 2, p. 125-139Article in journal (Refereed)
    Abstract [en]

    Bin planning (arrangements) is a key factor in the timber industry. Improper planning of the storage bins may lead to inefficient transportation of resources, which threaten the overall efficiency and thereby limit the profit margins of sawmills. To address this challenge, a simulation model has been developed. However, as numerous alternatives are available for arranging bins, simulating all possibilities will take an enormous amount of time and it is computationally infeasible. A discrete-event simulation model incorporating meta-heuristic algorithms has therefore been investigated in this study. Preliminary investigations indicate that the results achieved by GA based simulation model are promising and better than the other meta-heuristic algorithm. Further, a sensitivity analysis has been done on the GA based optimal arrangement which contributes to gaining insights and knowledge about the real system that ultimately leads to improved and enhanced efficiency in sawmill yards. It is expected that the results achieved in the work will support timber industries in making optimal decisions with respect to arrangement of storage bins in a sawmill yard.

  • 281.
    Shen, Yang
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Tuning Compiler Optimization Options via Simulated Annealing2007Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    To find a good set of options for a particular CPU and particular software is actually a difficult task. Some tool based on genetic algorithm like AcovEA exists, it will compile and run each program a lot of times, this is a obviously a huge problem if we want to use this tool with programs who have a long execution time, to try bigger problem, the classical example could be to optimize a long genetic algorithm search. The objective of this project is to develop a tool (we name it AcovSA) with the same purpose as AcovEA but based on Simulated Annealing. With bigger benchmark given – scheduling problem with some test data DAG (Directed Acyclic Graph) and finally find the good OOS (optimization options set), from more than 60 optimization options, for compiling the programs with GCC C compiler on a Linux platform. At last, comparing the benchmarks’ running time by compiling with the good OOS obtain from AcovSA and AcovEA to see both the advantages and disadvantages on two methods.

  • 282.
    Shi, Min
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Road and Traffic Signs Recognition using Vector Machines2006Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Intelligent Transportation System (ITS) is a system that builds a safe, effective and integrated transportation environment based on advanced technologies. Road signs detection and recognition is an important part of ITS, which offer ways to collect the real time traffic data for processing at a central facility. This project is to implement a road sign recognition model based on AI and image analysis technologies, which applies a machine learning method, Support Vector Machines, to recognize road signs. We focus on recognizing seven categories of road sign shapes and five categories of speed limit signs. Two kinds of features, binary image and Zernike moments, are used for representing the data to the SVM for training and test. We compared and analyzed the performances of SVM recognition model using different features and different kernels. Moreover, the performances using different recognition models, SVM and Fuzzy ARTMAP, are observed.

  • 283. Siril, Yella
    et al.
    Askar, Kalid
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Dougherty, Mark
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Expert system to calculate the cofficient of friction: an approach to enhance traffic safety2004In: Cybernetics and Intelligent Systems, 2004 IEEE Conference on, Singapore, 2004, Vol. 2, p. 803-808Conference paper (Other academic)
    Abstract [en]

    Friction plays a key role in causing slipperiness as a low coefficient of friction on the road may result in slippery and hazardous conditions. Analyzing the strong relation between friction and accident risk on winter roads is a difficult task. Many weather forecasting organizations use a variety of standard and bespoke methods to predict the coefficient of friction on roads. This article proposes an approach to predict the extent of slipperiness by building and testing an expert system. It estimates the coefficient of friction on winter roads in the province of Dalarna, Sweden using the prevailing weather conditions as a basis. Weather data from the road weather information system, Sweden (RWIS) was used. The focus of the project was to use the expert system as a part of a major project in VITSA, within the domain of intelligent transport systems

  • 284.
    Slottgård, Veronica
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Utvärdering av mobilforensiska verktyg.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays people manages much of their daily communication via their smartphone, both for

    leisure and business. Smartphones will therefore play an important role in forensic

    investigations since they contain a large amount of information. There are no mobil forensic

    tools on the market that can extract all of the information. It may differ what different

    software may produce and can also be good in different models of phones.

    This work examined for Skatteverket in Stockholm what method in XRY extracted what

    information regarding e-mail, SMS, call logs and contacts. Comparison was also performed

    between the tools XRY and Cellebrite to answer the question about which is preferable for the

    extraction of e-mail, text messages, call logs and contacts. Solution to easily print e-mail

    messages obtained were examined.

    Results from recoveries which then are compiled in tables showing what methods extract

    what information, for e-mail, text messages, call logs and contacts.

    The results emerging from the work also showed that XRY was better at extracting

    information for all the examined phones except one, primarily in the deleted items. It emerged

    during the work with XRY that it had a good reporting feature that facilitate printing the

    gained information such as e-mail.

  • 285.
    Srinivasan, BadriNarayanan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Unsupervised learning to cluster the disease stages in parkinson's disease2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Parkinson's disease (PD) is the second most common neurodegenerative disorder (after Alzheimer's disease) and directly affects upto 5 million people worldwide. The stages (Hoehn and Yaar) of disease has been predicted by many methods which will be helpful for the doctors to give the dosage according to it. So these methods were brought up based on the data set which includes about seventy patients at nine clinics in Sweden. The purpose of the work is to analyze unsupervised technique with supervised neural network techniques in order to make sure the collected data sets are reliable to make decisions. The data which is available was preprocessed before calculating the features of it. One of the complex and efficient feature called wavelets has been calculated to present the data set to the network. The dimension of the final feature set has been reduced using principle component analysis. For unsupervised learning k-means gives the closer result around 76% while comparing with supervised techniques. Back propagation and J4 has been used as supervised model to classify the stages of Parkinson's disease where back propagation gives the variance percentage of 76-82%. The results of both these models have been analyzed. This proves that the data which are collected are reliable to predict the disease stages in Parkinson's disease.

  • 286.
    Stefan, Vlad
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Discrete Event Simulation of a Sawmill Yard Using Multi-Agent System2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In direct reference to the saying “time is money”, nowadays scenario simulations play a key role in the tasks people perform. Optimizing the time length of tasks and synchronizing them properly is essential to increased profits in any line of business.

    In this thesis the Bergkvist-Insjön sawmill yard process will be computer simulated. As the number of trucks arriving at the sawmill is unknown, the unexpected arrival of trucks would produce a high pressure on internal resources and handling operations. The aim of this paper is to optimize the usage of the resources in the Bergkvist-Insjön sawmill, by running three different scenarios built based on the real system simulation.

    Scenario number three, in which a log stacker only has the tasks to unload the trucks and supply the measurement station, has been found most efficient. In the simulation of this scenario, the number of logs processed by the sawmill is the highest one. Also, the time spent by the log stackers between their tasks is the shortest one from all scenarios.

    The results of this thesis revealed that the most efficient improvement of the sawmill yard would be gained by a different tasks’ priority for the operating log stackers.

  • 287.
    Svenblad, Tobias
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    An Analysis of Using Blockchains for Processing and Storing Digital Evidence2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A review of digital forensics today shows that it could be exposed to threats jeopardizing the digital evidence integrity. There are several techniques to countermeasure this risk, one of which is the method that involves the use of blockchains. Blockchains use an advanced system to keep the data within it persistent and transparent, which makes it a natural candidate for everything integrity-sensitive. Several blockchain techniques and infrastructures have been described in this study, based on previous studies and other literature work. Interviews and experiments made a comparison between traditional digital forensic methodologies versus blockchains possible in later chapters. The results showed that blockchains could be the answer to securing digital evidence integrity. However, there is still a lot more work to be done before blockchains are ready to be implemented in production systems. The results of the blockchain analysis are presented such that they can be used as an aid to further research, either theoretically or practically, digital evidence blockchains.

  • 288.
    Szreder, Agnieszka
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Reimertz, Sara
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Utveckling av en Android applikation för upplysning om tillsatser i livsmedelsprodukter.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Additives in food is a hot topic where its needs are questioned. One people says that they can induce illnesses, while others feel that they save our lives [1]. By that means that some additives are necessary to prevent growth of dangerous bacteria, like the ones which can cause botulinum poisoning. Despite of that fact, it is believed that a consumer have the right to be aware of the additives impact on their health, good and bad. This was a foundation of the created application where the user has the possibility to get that information. For the information to be simple and fast to take part of, a barcode reader is used to scan the product and get relevant details direct on mobiles screen. It was even considered that there could be a need of information about allergens in food. Due to that, an extra function has been developed where the user can choose to be warned about certain allergens. A warning is shown each time some of the chosen allergens is found in the food.

  • 289.
    Thelander, Pierre
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Multifaktorautentisering mot Office 365 inom små till medelstora företag: En studie av autentiseringsmetoder2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today we live in a digitalized society, where the daily IT- operations often are stored in different environments. CloudPro AB is a company whose using Office 365 and wants to find out what authorization methods that is being offered and which one is the safest and most user-friendly. The study will focus on the problem Security Fatigue, the study of how users feel reluctant towards handling computer safety. The purpose is to look at the authorization methods for Office 365 and highlight both weaknesses and strengths. It will also test how user-friendly the different authorization methods are. To answer this, two different methods have been used. One literal study and one practical. The result presents both the weaknesses and strengths which comes along with these methods and a demonstration shows the different methods linked to certain scenarios. The results show that the authorization method "push notification" is the method that fill most of the companies’ desires concerning safety and how user friendly it is.

  • 290.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Bergquist, Filip
    Johansson, Dongni
    Memedi, Mevludin
    Nyholm, Dag
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Sensor-based algorithmic dosing suggestions for oral administration of levodopa/carbidopa microtablets for Parkinson's disease: a first experience2019In: Journal of Neurology, ISSN 0340-5354, E-ISSN 1432-1459, Vol. 266, no 3, p. 651-658Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Dosing schedules for oral levodopa in advanced stages of Parkinson's disease (PD) require careful tailoring to fit the needs of each patient. This study proposes a dosing algorithm for oral administration of levodopa and evaluates its integration into a sensor-based dosing system (SBDS).

    MATERIALS AND METHODS: In collaboration with two movement disorder experts a knowledge-driven, simulation based algorithm was designed and integrated into a SBDS. The SBDS uses data from wearable sensors to fit individual patient models, which are then used as input to the dosing algorithm. To access the feasibility of using the SBDS in clinical practice its performance was evaluated during a clinical experiment where dosing optimization of oral levodopa was explored. The supervising neurologist made dosing adjustments based on data from the Parkinson's KinetiGraph™ (PKG) that the patients wore for a week in a free living setting. The dosing suggestions of the SBDS were compared with the PKG-guided adjustments.

    RESULTS: The SBDS maintenance and morning dosing suggestions had a Pearson's correlation of 0.80 and 0.95 (with mean relative errors of 21% and 12.5%), to the PKG-guided dosing adjustments. Paired t test indicated no statistical differences between the algorithmic suggestions and the clinician's adjustments.

    CONCLUSION: This study shows that it is possible to use algorithmic sensor-based dosing adjustments to optimize treatment with oral medication for PD patients.

  • 291.
    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)
  • 292.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Nyholm, Dag
    Senek, Marina
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Individual dose-response models for levodopa infusion dose optimization2018In: International Journal of Medical Informatics, ISSN 1386-5056, E-ISSN 1872-8243, Vol. 112, p. 137-142Article in journal (Refereed)
    Abstract [en]

    Background and Objective

    To achieve optimal effect with continuous infusion treatment in Parkinson’s disease (PD), the individual doses (morning dose and continuous infusion rate) are titrated by trained medical personnel. This study describes an algorithmic method to derive optimized dosing suggestions for infusion treatment of PD, by fitting individual dose-response models. The feasibility of the proposed method was investigated using patient chart data.

    Methods

    Patient records were collected at Uppsala University hospital which provided dosing information and dose-response evaluations. Mathematical optimization was used to fit individual patient models using the records’ information, by minimizing an objective function. The individual models were passed to a dose optimization algorithm, which derived an optimized dosing suggestion for each patient model.

    Results

    Using data from a single day’s admission the algorithm showed great ability to fit appropriate individual patient models and derive optimized doses. The infusion rate dosing suggestions had 0.88 correlation and 10% absolute mean relative error compared to the optimal doses as determined by the hospital’s treating team. The morning dose suggestions were consistency lower that the optimal morning doses, which could be attributed to different dosing strategies and/or lack of on-off evaluations in the morning.

    Conclusion

    The proposed method showed promise and could be applied in clinical practice, to provide the hospital personnel with additional information when making dose adjustment decisions.

  • 293.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Senek, Marina
    Uppsala University Hospital.
    Dag, Nyholm
    Uppsala University Hospital.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Minimizing levodopa titration period for Parkinson’s disease2016Conference paper (Other academic)
  • 294.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Bergquist, Filip
    Gothenburg University.
    Constantinescu, Radu
    Gothenburg University.
    Nyholm, Dag
    Dept. of Neuroscience, Neurology, Uppsala University.
    Senek, Marina
    Dept. of Neuroscience, Neurology, Uppsala University.
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering. Informatics, School of Business, Örebro University.
    Using measurements from wearable sensors for automatic scoring of Parkinson's disease motor states: Results from 7 patients2017In: Engineering in Medicine and Biology Society (EMBC), 2017 39th Annual International Conference of the IEEE, IEEE, 2017, p. 131-134Conference paper (Refereed)
    Abstract [en]

    The objective of this study was to investigate the validity of an objective gait measure for assessment of different motor states of advanced Parkinson's disease (PD) patients. Seven PD patients performed a gait task up to 15 times while wearing sensors on their upper and lower limbs. Each task was performed at specific points during a test day, following a single dose of levodopa-carbidopa. At the time of the tasks the patients were video recorded and three movement disorder experts rated their motor function on three clinical scales: a treatment response scale (TRS) that ranged from −3 (very bradykinetic) to 0 (ON) to +3 (very dyskinetic), a dyskinesia score that ranged from 0 (no dyskinesia) to 4 (extreme dyskinesia), and a bradykinesia score that ranged from 0 (no bradykinesia) to 4 (extreme bradykinesia). Raw accelerometer and gyroscope data of the sensors were processed and analyzed with time series analysis methods to extract features. The utilized features quantified separate limb movements as well as movement symmetries between the limbs. The features were processed with principal component analysis and the components were used as predictors for separate support vector machine (SVM) models for each of the three scales. The performance of each model was evaluated in a leave-one-patient out setting where the observations of a single patient were used as the testing set and the observations of the other 6 patients as the training set. Root mean square error (RMSE) and correlation coefficients for the predictions showed a good ability of the models to map the sensor data into the rating scales. There were strong correlations between the SVM models and the mean ratings of TRS (0.79; RMSE=0.70), bradykinesia score (0.79; RMSE=0.47), and bradykinesia score (0.78; RMSE=0.46). The results presented in this paper indicate that the use of wearable sensors when performing gait tasks can generate measurements that have a good correlation to subjective expert assessments.

  • 295.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Memedi, Mevludin
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Nyholm, Dag
    The effect of continuous levodopa treatment during the afternoon hours2019In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 139, no 1, p. 70-75Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The aim of this retrospective study was to investigate if patients with PD, who are treated with levodopa-carbidopa intestinal gel (LCIG), clinically worsen during the afternoon hours and if so, to evaluate whether this occurs in all LCIG-treated patients or in a sub-group of patients.

    METHODS: Three published studies were identified and included in the analysis. All studies provided individual response data assessed on the treatment response scale (TRS) and patients were treated with continuous LCIG. Ninety-eight patients from the three studies fulfilled the criteria. T-tests were performed to find differences on the TRS values between the morning and the afternoon hours, linear mixed effect models were fitted on the afternoon hours' evaluations to find trends of wearing-off, and patients were classified into three TRS categories (meaningful increase in TRS, meaningful decrease in TRS, non -meaningful increase or decrease).

    RESULTS: In all three studies significant statistical differences were found between the morning TRS values and the afternoon TRS values (p-value <= 0.001 in all studies). The linear mixed effect models had significant negative coefficients for time in two studies, and 48 out of 98 patients (49%) showed a meaningful decrease of TRS during the afternoon hours.

    CONCLUSION: The results from all studies were consistent, both in the proportion of patients in the three groups and the value of TRS decrease in the afternoon hours. Based on these findings there seems to be a group of patients with predictable "off" behavior in the later parts of the day. This article is protected by copyright. All rights reserved.

  • 296.
    Thomas, Ilias
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Westin, Jerker
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Alam, Moudud
    Dalarna University, School of Technology and Business Studies, Statistics.
    Bergquist, F.
    Nyholm, D.
    Senek, M.
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    A treatment–response index from wearable sensors for quantifying Parkinson's disease motor states2018In: IEEE journal of biomedical and health informatics, ISSN 2168-2194, E-ISSN 2168-2208, Vol. 22, no 5, p. 1341-1349Article in journal (Refereed)
    Abstract [en]

    The goal of this study was to develop an algorithm that automatically quantifies motor states (off,on,dyskinesia) in Parkinson's disease (PD), based on accelerometry during a hand pronation-supination test. Clinician's ratings using the Treatment Response Scale (TRS), ranging from -3 (very Off) to 0 (On) to +3 (very dyskinetic), was used as target. For that purpose, 19 participants with advanced PD and 22 healthy persons were recruited in a single center open label clinical trial in Uppsala, Sweden. The trial consisted of single levodopa dose experiments for the people with PD (PwP), where participants were asked to perform standardized wrist rotation tests, using each hand, before and at pre-specified time points after the dose. The participants used wrist sensors containing a 3D accelerometer and gyroscope. Features to quantify the level, variation and asymmetry of the sensor signals, three-level Discrete Wavelet Transform features and approximate entropy measures were extracted from the sensors data. At the time of the tests, the PwP were video recorded. Three movement disorder specialists rated the participants’ state on the TRS scale. A Treatment Response Index from Sensors (TRIS) was constructed to quantify the motor states based on the wrist rotation tests. Different machine learning algorithms were evaluated to map the features derived from the sensor data to the ratings provided by the three specialists. Results from cross validation, both in 10-fold and a leave-one-individual out setting, showed good predictive power of a support vector machine model and high correlation to the TRS scale. Values at the end tails of the TRS scale were under and over predicted due to the lack of observations at those values but the model managed to accurately capture the dose - effect profiles of the patients. In addition, the TRIS had good test-retest reliability on the baseline levels of the PD participants (Intraclass correlation coefficient of 0.83) and reasonable sensitivity to levodopa treatment (0.33 for the TRIS). For a series of test occasions the proposed algorithms provided dose - effect time profiles for participants with PD, which could be useful during therapy individualization of people suffering from advanced PD

  • 297.
    Tilander, Anders
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Stulna användarkonton: Risker, åtgärder och alternativa autentiseringsmetoder2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The focus of this study is based around the fact that a severe amount of stolen user accounts can be found on the internet today. With this knowledge three research question were produced which are: Could stolen user accounts propose any risks? Which countermeasures exist to prevent a possible security breach? Do any alternative authentications methods that could replace the traditional password authentication method exist today?

    A study where conducted regarding who might be the victim of attacks where user accounts are stolen followed by a presentation of the most commonly used attack methods. Potential risk factors for companies, organizations and individuals was investigated as well as the negative aspects of password re-use. A software consisting of two python scripts and a web application with corresponding web and database servers was developed for experimental and analytical purposes. The software was then used to give an overview regarding the extent of stolen user accounts by compiling several stolen user accounts together with encrypted passwords in a searchable database. A series of forced decryption methods was performed in order to test the security level of the encrypted passwords and explain how salted passwords could offer extra security against these types of attacks. This was followed by safety suggestions corresponding to the earlier presented security threats. A number of alternative authentication methods in regards to the traditional password authentications was then presented which also included biometric based authentication.

    The research question are answered in the discussion and conclusion chapter which states that one of the most common risk factors are identity theft which could lead to economic damages for the victim. As risk minimization an implementation of technical safety measures, staff training and salted password encryption could be used since attacks seem to be targeted mostly based on the security level of the victim. Two-factor authentication method might serve as the best replacement for passwords today since password based authentication in itself constitutes a security risk.

  • 298.
    Tunander, Hans
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Livslängdskontroll för verktyg med RFID-teknik2006Independent thesis Basic level (degree of Bachelor)Student thesis
  • 299.
    Udaya Kumar, Magesh Kumar
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Classification of Parkinson’s Disease using MultiPass Lvq,Logistic Model Tree,K-Star for Audio Data set: Classification of Parkinson Disease using Audio Dataset2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Parkinson's disease (PD) is a degenerative illness whose cardinal symptoms include rigidity, tremor, and slowness of movement. In addition to its widely recognized effects PD can have a profound effect on speech and voice.The speech symptoms most commonly demonstrated by patients with PD are reduced vocal loudness, monopitch, disruptions of voice quality, and abnormally fast rate of speech. This cluster of speech symptoms is often termed Hypokinetic Dysarthria.The disease can be difficult to diagnose accurately, especially in its early stages, due to this reason, automatic techniques based on Artificial Intelligence should increase the diagnosing accuracy and to help the doctors make better decisions. The aim of the thesis work is to predict the PD based on the audio files collected from various patients.Audio files are preprocessed in order to attain the features.The preprocessed data contains 23 attributes and 195 instances. On an average there are six voice recordings per person, By using data compression technique such as Discrete Cosine Transform (DCT) number of instances can be minimized, after data compression, attribute selection is done using several WEKA build in methods such as ChiSquared, GainRatio, Infogain after identifying the important attributes, we evaluate attributes one by one by using stepwise regression.Based on the selected attributes we process in WEKA by using cost sensitive classifier with various algorithms like MultiPass LVQ, Logistic Model Tree(LMT), K-Star.The classified results shows on an average 80%.By using this features 95% approximate classification of PD is acheived.This shows that using the audio dataset, PD could be predicted with a higher level of accuracy.

  • 300.
    Ullah, Noor
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    ANFIS BASED MODELS FOR ACCESSING QUALITY OF WIKIPEDIA ARTICLES2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Due to the free nature of Wikipedia and allowing open access to everyone to edit articles the quality of articles may be affected. As all people don’t have equal level of knowledge and also different people have different opinions about a topic so there may be difference between the contributions made by different authors. To overcome this situation it is very important to classify the articles so that the articles of good quality can be separated from the poor quality articles and should be removed from the database. The aim of this study is to classify the articles of Wikipedia into two classes class 0 (poor quality) and class 1(good quality) using the Adaptive Neuro Fuzzy Inference System (ANFIS) and data mining techniques. Two ANFIS are built using the Fuzzy Logic Toolbox [1] available in Matlab. The first ANFIS is based on the rules obtained from J48 classifier in WEKA while the other one was built by using the expert’s knowledge. The data used for this research work contains 226 article’s records taken from the German version of Wikipedia. The dataset consists of 19 inputs and one output. The data was preprocessed to remove any similar attributes. The input variables are related to the editors, contributors, length of articles and the lifecycle of articles. In the end analysis of different methods implemented in this research is made to analyze the performance of each classification method used.

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