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  • 51.
    Fredriksson, Joakim
    et al.
    Halmstad University, School of Information Technology.
    Höppner, Falk
    Halmstad University, School of Information Technology.
    Chatbot for Information Retrieval from Unstructured Natural Language Documents2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis brings forward the development of a chatbot which retrieves information from a data source consisting of unstructured natural language text. This project was made in collaboration with the company Jayway in Halmstad. Elasticsearch was used to create the search function and the service Dialogflow was used to process the natural language input from the user. A Python script was created to retrieve the information from the data source, and a request handler was written which connected the tools together to create a working chatbot. The chatbot correctly answers questions with a accuracy of 72% according to testing with a sample of n = 25. The testing consisted of asking the chatbot questions and determining if the answer is correct. Possible further research could be done to explore how chatbots might help the elderly or people with disabilities use the web with a natural dialogue instead of a traditional user interface.

  • 52.
    GE, LIN
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    NI, DANQING
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    A MOD Player for GBA2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

       This bachelor thesis describes the development of a MOD music player to run on GBA (Game Boy Advance) for Lypson Game Engine. GBA is a basic platform for embedded development, and the stereo system makes it possible to use the platform as a music player. The sound players of the GBA for Lypson Game Engine were designed to play wave files and the size of typical wave files is in the order of megabytes. MOD files are much smaller when compared with wave ones. Therefore, to avoid consuming the resources of the CPU and memory to process and store wave files, the use of MOD files represents a better alternative.The development took C++ as programming language and the development platform used was HAM. The first step was to obtain samples of music, and then control the hardware of GBA to play sound. After that, came the phase of combining it with Lipson Game Engine. These tasks enabled the acquisition of knowledge about the frame of MOD files; learning how to make the GBA play sound and mastering the operating instruction of GBA hardware by the process of development. In addition, it provided a chance to learn about embedded development, which represented a starting point to learn about embedded programming in general.As for the main result, it was achieved by the successful development of the MOD Player, which is now running on the Lypson Game Engine. As the MOD files are of small size, the music player is more efficient when compared with those previously used.

  • 53.
    Gebler, Daniel
    et al.
    Vrije Universiteit, Amsterdam, The Netherlands.
    Goriac, Eugen-Ioan
    Reykjavik University, Reyjkjavik, Iceland.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Algebraic Meta-Theory of Processes with Data2013In: Proceedings Combined 20th International Workshop on Expressiveness in Concurrency and 10th Workshop on Structural Operational Semantics / [ed] Johannes Borgström & Bas Luttik, Open Publishing Association , 2013, p. 63-77Conference paper (Refereed)
    Abstract [en]

    There exists a rich literature of rule formats guaranteeing different algebraic properties for formalisms with a Structural Operational Semantics. Moreover, there exist a few approaches for automatically deriving axiomatizations characterizing strong bisimilarity of processes. To our knowledge, this literature has never been extended to the setting with data (e.g. to model storage and memory). We show how the rule formats for algebraic properties can be exploited in a genericmanner in the setting with data. Moreover, we introduce a new approach for deriving sound and ground-complete axiom schemata for a notion of bisimilarity with data, called stateless bisimilarity, based on intuitive auxiliary function symbols for handling the store component. We do restrict, however, the axiomatization to the setting where the store component is only given in terms of constants. © Gebler, Goriac & Mousavi.

  • 54.
    Gidensköld, Carl Henrik
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Webbaserat system för kundstatistik: Hemsida24 Analytics2010Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    Den här rapporten är baserad på ett examensarbete som är gjort för Hemsida24 där uppgiften var att skapa ett webbaserat system för att grafiskt visa statistik om deras kunder. Det skapade statistiksystemet har fått namnet Hemsida24 Analytics.I rapporten redovisas hur ovan nämna statistikverktyg har kommit till, samt hur det fungerar. Kundstatistiken visas på ett stilrent sätt med hjälp av amCharts flashbaserade grafer. Baserat på information från Hemsida24:s databas beräknades kundstatistiken och visades därefter i grafer.

    Programmeringen av Hemsida24 Analytics har i största hand gjorts objektorienterat i PHP. Utöver PHP har Zend Framework, MVC, MySQL, HMTL, CSS och jQuery haft en viktig roll under projektets gång.

    I graferna finns möjligheten att visa framtida prognoser. För att räkna ut prognoser för graferna används både linjära ekvationer och andragradsekvationer.

    I rapporten redovisas det slutgiltiga resultatet i jämförelse med projektplaneringen och en tidigare framtagen skiss. Det ges även förslag på eventuell fortsatt utveckling av Hemsida24 Analytics.

  • 55.
    Grahl, Daniel
    et al.
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    Bubel, Richard
    Technische Universität Darmstadt, Darmstadt, Germany.
    Mostowski, Wojciech
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Schmitt, Peter H.
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    Ulbrich, Mattias
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    Weiß, Benjamin
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    Modular Specification and Verification2016In: Deductive Software Verification – The KeY Book: From Theory to Practice / [ed] Wolfgang Ahrendt, Bernhard Beckert, Richard Bubel, Reiner Hähnle, Peter H. Schmitt & Mattias Ulbrich, Heidelberg: Springer, 2016, p. 289-351Chapter in book (Other academic)
    Abstract [en]

    In this chapter, concepts already addressed in previous chapters are reconsidered and extended to cater for modularity. In particular, it is shown how method contracts can be used in proofs (as opposed to being verified themselves). Another central topic is nonfunctional framing information, i.e., information on what locations a method may write to or read from. But, there are also items that are discussed here in depth for the first time: model methods, an abstraction of Java methods that are only used in specification, verification of recursive methods, and object invariants. For any of the arising proof obligations the calculus rules needed to dispatch them are shown. © Springer International Publishing AG 2016.

  • 56.
    Green, Jonas
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Delén, Johan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Trådlös styrning av larmsystem: Kandidatuppsats2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lansen Technology develops and sells alarm systems. The communication between the system devices are wireless. The radio protocol used by the system is developed by Lansen with the purpose to be energy efficient. The alarm systems target groups are individuals, businesses and government agencies. The current system is installed, configured and controlled from a control panel for all audiences. Some operations are also available using a mobile phone via a GSM network. Lansen Technology has a request to move more of the functionality to a mobile device and avoid the cost of using the GSM network used today. The target group for the application is primarily users that want instant access to information within the network. The project has mainly consisted of two parts. The first part of the project was to investigate two different wireless technologies that were relevant to the project. The investigation showed that Bluetooth was the best choice based on the requirements of the alarm system. Bluetooth was then integrated to the existing alarm system. The second part consisted of developing software to operate the alarm system from a PDA running Windows Mobile. An application was developed successfully and it can perform the majority of the functions specified by Lansen. The idea of remote controlling an alarm system from a mobile device has resulted in a successful project. Lansen Technology develops and sells alarm systems. The communication between the system devices are wireless. The radio protocol used by the system is developed by Lansen with the purpose to be energy efficient. The alarm systems target groups are individuals, businesses and government agencies. The current system is installed, configured and controlled from a control panel for all audiences. Some operations are also available using a mobile phone via a GSM network. Lansen Technology has a request to move more of the functionality to a mobile device and avoid the cost of using the GSM network used today. The target group for the application is primarily users that want instant access to information within the network. The project has mainly consisted of two parts. The first part of the project was to investigate two different wireless technologies that were relevant to the project. The investigation showed that Bluetooth was the best choice based on the requirements of the alarm system. Bluetooth was then integrated to the existing alarm system. The second part consisted of developing software to operate the alarm system from a PDA running Windows Mobile. An application was developed successfully and it can perform the majority of the functions specified by Lansen. The idea of remote controlling an alarm system from a mobile device has resulted in a successful project.

  • 57.
    Haage, Mathias
    et al.
    Department of Computer Science, Lund University, Lund, Sweden.
    Malec, Jacek
    Department of Computer Science, Lund University, Lund, Sweden.
    Nilsson, Anders
    Department of Computer Science, Lund University, Lund, Sweden.
    Nilsson, Klas
    Department of Computer Science, Lund University, Lund, Sweden.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent Systems´ laboratory.
    Declarative Knowledge-Based Reconfiguration of Automation Systems Using a Blackboard Architecture2011In: / [ed] Kofod-Petersen A., Langseth H., Heintz F., Amsterdam: IOS Press, 2011, p. 163-172Conference paper (Refereed)
    Abstract [en]

    This article describes results of the work on knowledge representation techniques chosen for use in the European project SIARAS (Skill-Based Inspection and Assembly for Reconfigurable Automation Systems). Its goal was to create intelligent support system for reconfiguration and adaptation of robot-based manufacturing cells. Declarative knowledge is represented first of all in an ontology expressed in OWL, for a generic taxonomical reasoning, and in a number of special-purpose reasoning modules, specific for the application domain. The domaindependent modules are organized in a blackboard-like architecture. © 2011 The authors and IOS Press. All rights reserved.

  • 58.
    Hajiaghayi, Mohammad Taghi
    et al.
    University of Maryland, College Park, MD, USA.
    Mousavi, Mohammad RezaHalmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Topics in Theoretical Computer Science: The First IFIP WG 1.8 International Conference, TTCS 2015, Tehran, Iran, August 26-28, 2015, Revised Selected Papers2016Conference proceedings (editor) (Refereed)
  • 59.
    H.Daryani, Sara
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Taslimi, Pouria
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Integrated Security by using MPLS-VPN for Retail-Banking Network: Case study Mehr bank, Iran2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The studied application area is a private bank with different branches located in different provinces around the country. There was not integrated security solution to provide communication among different branches. Some of these branches could communicate through the satellite and the others could communicate through a different technology, such as asynchronous transfer mode (ATM).

    Different bank security policies were applied and maintained for different branches separately. In addition, the number of branches is expected to grow during coming year in each province.

    The old topology was partial mesh and it could not support enough redundancy in case of disruption. If a connection between two branches failed, other branches might lose their connectivity as well. In addition, it could not achieve optimum routing.

    Providing integrated quality of service (QoS) for the wide area network (WAN) by using different technologies is not easy to achieve, and it causes so many problems for the system. The bank uses a variety of protocols for different applications, depending on its demand, so the new applied technology should not depend on protocols, or at least should support different protocols at a same time. In the old technology, the bank was responsible for granting availability and connectivity maintenance. Providing proper bandwidth is an important aspect in the bank scenario and for the old technology; supplying enough bandwidth was costly.

    As mentioned above, the old applied technology was dependent upon different protocols. Therefore, packets in different open system interconnection layers (OSI layers) would have to check thoroughly to find the source/ destination address, data and so on, to reach the correct destination. This might cause security problems for entire system. In addition, processing packet in each layer of the OSI model is time consuming.

    One important aspect for the retail-banking scenario is considering all features of the security domain, such as security policy, information security, physical security, access level control, integrated security for the system and so on. Some features of the security domain in this project were not covering completely, such as integrated information security, merged security policy, and integrated physical security for the system.

    In this project, all mentioned problems are solved by implementing a specific communication technology which can overcome the problems above. This technology supports multiple protocols, and it provides fast and secure communication. It can also cover redundancy and it does not cost as much as previous technologies like ATM and satellite. Easy provisioning is one feature of this technology. In this technology, the service provider is responsible for granting availability and connectivity maintenance.

    The mentioned features of the security domain, which were not covered by the old technology, will be covered by a proper, integrated security solution. The IP-based physical security systems provide centralized monitoring and they can define a merged security policy for all different branches around the country. Specific, pre-defined scenarios are created for different events in different situations.

  • 60.
    Hedenberg, Klas
    et al.
    School of Tecnology and Society, University of Skövde, Skövde, Sweden.
    Åstrand, Björn
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    A Trinocular Stereo System for Detection of Thin Horizontal Structures2008In: Advances in Electrical and Electronics Engineering: IAENG Special Edition of the World Congress on Engineering and Computer Science 2008, WCECS '08 / [ed] Sio-Iong Ao, Los Alamitos: IEEE Computer Society, 2008, p. 211-218Conference paper (Refereed)
    Abstract [en]

    Many vision-based approaches for obstacle detection often state that vertical thin structure is of importance, e.g. poles and trees. However, there are also problem in detecting thin horizontal structures. In an industrial case there are horizontal objects, e.g. cables and fork lifts, and slanting objects, e.g. ladders, that also has to be detected. This paper focuses on the problem to detect thin horizontal structures. We introduce a test apparatus for testing thin objects as a complement for the test pieces for human safety described in the European standard EN 1525 safety of industrial trucks - driverless trucks and their systems. The system uses three cameras, situated as a horizontal pair and a vertical pair, which makes it possible to also detect thin horizontal structures. A sparse disparity map based on edges and a dense disparity map is used to identify problems with a trinocular system. Both methods use the sum of absolute difference to compute the disparity maps. Tests show that the proposed trinocular system detects all objects at the test apparatus. If a sparse or dense method is used is not critical. Further work will implement the algorithm in real time and verify it on a final system in many types of scenery.

  • 61.
    Henfridsson, Ola
    et al.
    Viktoria Institute, Göteborg.
    King, John
    University of Michigan.
    Mercer, Glenn
    McKinsey Consulting.
    Pavlich, Dave
    Yellow Roadway.
    Scacchi, Walt
    University of California, Irvine.
    Socio-Technical Research Challenges in Ubiquitous Computing: The Case of Telematics2005In: Designing Ubiquitous Information Environments: Socio-Technical Issues and Challenges, New York: Springer, 2005, p. 359-362Chapter in book (Other (popular science, discussion, etc.))
  • 62.
    Henfridsson, Ola
    et al.
    Viktoria Institute, Göteborg.
    Lindgren, Rikard
    Viktoria Institute, Göteborg.
    Multi-Contextuality in Ubiquitous Computing: Investigating the Car Case through Action Research2005In: Information and organization, ISSN 1471-7727, E-ISSN 1873-7919, Vol. 15, no 2, p. 95-124Article in journal (Refereed)
    Abstract [en]

    Ubiquitous computing envisions seamless access of mass-scale services over the multitude of contexts that users encounter in their everyday mobility. However, to be successful such computing must simultaneously be designed to provide transparent, integrated, and convenient support in localized use contexts. Thus, the issue of multi-contextuality makes the design of ubiquitous computing services and environments a challenging endeavor. While ubiquitous computing requires attention to the multi-contextuality of people’s mobile device use encompassing spatial, temporal, and social dimensions of mobility, the typical avenue for IS research studies has been the single context (e.g., team, organization, or inter-organizational).

    This paper reports on a grounded action research study with the objective of developing and testing design principles for handling multi-contextuality in an increasingly important ubiquitous computing environment – the car. Already supporting people’s everyday mobility and promising to provide ubiquitous availability of computing and communication infrastructure, the car is indeed a relevant setting for investigating the co-existence of different use contexts in ubiquitous computing. Contributing to the early stage of the ubiquitous computing research tradition, this paper not only empirically demonstrates that the car as a ubiquitous computing environment can improve the convenience of people’s everyday mobile device use by providing multi-contextual support. The paper also suggests our design principles and their associated socio-technical implications to be valid for other ubiquitous computing environments. Indeed, synchronizing fluid use patterns, scaling service manipulation, and signaling context-switches through awareness support lie at the heart of weaving ubiquitous computing environments conveniently into the fabric of people’s everyday mobility.

  • 63.
    Hoang, Hoai
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Enhancing the Performance of Distributed Real-time Systems2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Advanced embedded systems can consist of many sensors, actuators and processors that are deployed on one or several boards, while having a demand of interacting with each other and sharing resources. Communication between different components usually has strict timing constraints. There is thus a strong need to provide solutions for time critical communication. This thesis focuses on both the support of real-time services over standard switched Ethernet networks and the improvement of systems' real-time characteristics, such as reducing delay and jitter in processors and on communication links.

    Switched Ethernet has been chosen in this work because of its major advantages in industry; it supports higher bit-rates than most other current LAN (Local Area Network) technologies, including field buses, still at a low cost. We propose using a star network topology with a single Ethernet switch. Each node is connected to a separate port of the switch via a full-duplex link, thereby eliminating collisions. A solid real-time communication protocol for switched Ethernet networks is proposed in the thesis, including a real-time layer between the Ethernet layer and the TCP/IP suite. The network has the capability of supporting both real-time and non real-time traffic and assuring adaptation to the surrounding protocol standards.

    Most embedded systems work in a dynamic environment, where the precise behavior of the network traffic can usually not be predicted. To support real-time services, we have chosen the Earliest Deadline scheduling algorithm (EDF) because of its optimality, high efficiency and suitability for being used in adaptive schemes. To be able to increase the amount of guaranteed real-time traffic, the notion of Asymmetric Deadline Partitioning Scheme (ADPS) is introduced. ADPS allows distribution of the end-to-end deadline of a message, sent from any source node in the network to any destination node via the switch, into two sub-deadlines, one for each hop according to the load of the physical link that it must traverse.

    For the EDF scheduling algorithm, the feasibility test is one of the most important techniques that provides us with information about whether or not the real-time traffic can be guaranteed by the network. With the same computational complexity as the feasibility test, a method has been developed to compute the minimum EDF-feasible deadline for a real-time task. The importance of this method in real-time applications lies in that it can be effectively used to reduce the response times of specific control activities or limit their input-output jitter. To allow more flexibility in the control of delay and jitter in real-time systems, a general approach for reducing task deadlines according to the requirements of individual tasks has been developed. The method allows the user to specify a deadline reduction factor for each task in order to better exploit the available slack according to the tasks' actual requirements.

  • 64.
    Hortling, Johan
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Bergh, Erik
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Karlsson, Daniel
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Konstruktion och penetrationstestning av VoIP-system2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    VoIP systems in enterprises are becoming more common. Security should then be followed to avoid threats against confidentiality, integrity and availability. This report shows the results from two different VoIP systems security using practical penetration test scenarios in a laboratory environment. A statement of tools that are used for safety tests on VoIP and methods for this, is presented in the report with explanatory text and tables.

  • 65.
    Huisman, Marieke
    et al.
    University of Twente, Enschede, The Netherlands.
    Monahan, Rosemary
    Maynooth University, Maynooth, Ireland.
    Müller, Peter
    ETH Zurich, Zürich, Switzerland.
    Mostowski, Wojciech
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ulbrich, Mattias
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    VerifyThis 2017: A Program Verification Competition2017Report (Other academic)
    Abstract [en]

    VerifyThis 2017 was a two-day program verification competition which took place from April 22-23rd, 2017 in Uppsala, Sweden as part of the European Joint Conferences on Theory and Practice of Software (ETAPS 2017). It was the sixth instalment in the VerifyThis competition series. This article provides an overview of the VerifyThis 2017 event, the challenges that were posed during the competition, and a high-level overview of the solutions to these challenges. It concludes with the results of the competition.

  • 66.
    Häägg, Anton
    et al.
    Halmstad University, School of Information Technology.
    Arvidsson, Linus
    Halmstad University, School of Information Technology.
    Epilepsiarmband: Ett system utformat för detektering samt larmande vid epileptiskt anfall2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Epilepsy is a disability with a large research field but yet with little knowledge and understanding about finding a cure. The common idea as to why an epileptic seizure is triggered is because of over activity in the neurons of the brain. More than 60 000 people in Sweden suffer from epilepsy. Damages from an epileptic seizure can be life threatening if left uncontrolled and a solution is needed in order to detect and alarm if a seizure has appeared. This project refers to building a system that can detect a seizure and locate the position of the patient having the seizure. This system also creates the possibility for a contact person to take part of the information. As there were no persons with the diagnose epilepsy at hand, the project group decided that simulated seizures were necessary. Development of the system has been categorised into three subsystems. The subsystems are a bracelet unit, a mobile application and a cloud-service. The projects subsystems were developed and the system was completed. A bracelet unit was created. This bracelet is able to detect if an epileptic seizure has occurred. A Bluetooth low energy connection between the bracelet and the mobile application was enabled making it possible for an alarm to be sent to a contact person during a seizure.

  • 67.
    Iftikhar, Amjad
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Shah, Muhammad Aoon
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Latif, Fowad
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Multi-Protocol Label Switching To Support Quality of Service Needs2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Multi-Protocol Label Switching (MPLS) is a technique that can be used to improve the performance of a computer communication network. By use of MPLS, data packets can be switched on the basis of labels rather than routed on the basis of destination address. MPLS supports different features like QoS, traffic engineering and VPNs etc.

    This thesis evaluates the working and performance of MPLS and its support for Quality of Service. QoS is required in the network when real time traffic is transported.

    In this thesis it is described, how QoS guarantees are assigned to the IP packets and how MPLS QoS environment differs from the traditional IP routing environment. MPLS QoS works as the IP QoS, but MPLS QoS enhances the capability of network as compared to the IP QoS based network.

    The thesis studies the use of MPLS in an integrated environment with DiffServ QoS model and also implements MPLS QoS in a Lab environment to compare MPLS QoS with IP QoS. Real time traffic faces longer delays in IP QoS based networks. MPLS QoS reduces the delays in real time traffic transmission.

    The study results and the practical implementations show that MPLS QoS provide much better results than simple IP QoS.

  • 68.
    Inoue, Jun
    et al.
    National Institute of Advanced Industrial Science and Technology, Ikeda, Osaka, Japan.
    Taha, Walid
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Reasoning about multi-stage programs2016In: Journal of functional programming (Print), ISSN 0956-7968, E-ISSN 1469-7653, Vol. 26, article id e22Article in journal (Refereed)
    Abstract [en]

    We settle three basic questions that naturally arise when verifying code generators written in multi-stage functional programming languages. First, does adding staging to a language compromise any equalities that hold in the base language? Unfortunately it does, and more care is needed to reason about terms with free variables. Second, staging annotations, as the name "annotations" suggests, are often thought to be orthogonal to the behavior of a program, but when is this formally guaranteed to be true? We give termination conditions that characterize when this guarantee holds. Finally, do multi-stage languages satisfy useful, standard extensional properties, for example, that functions agreeing on all arguments are equivalent? We provide a sound and complete notion of applicative bisimulation, which establishes such properties or, in principle, any valid program equivalence. These results yield important insights into staging and allow us to prove the correctness of quite complicated multi-stage programs. © Cambridge University Press 2016.

  • 69.
    Jafari Moghadamfard, Ramtin
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Payvar, Saeid
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    The Potential of Visual Features: to Improve Voice Recognition Systems in Vehicles Noisy Environment2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Multimodal biometric systems have been subject of study in recent decades, theirunique characteristic of Anti spoofing and liveness detection plus ability to deal withaudio noise made them technology candidates for improving current systems such asvoice recognition, verification and identification systems.In this work we studied feasibility of incorporating audio-visual voice recognitionsystem for dealing with audio noise in the truck cab environment. Speech recognitionsystems suffer from excessive noise from the engine and road traffic and cars stereosystem. To deal with this noise different techniques including active and passive noisecancelling have been studied.Our results showed that although audio-only systems are performing better in noisefree environment their performance drops significantly by increase in the level of noisein truck cabins, which by contrast does not affect the performance of visual features.Final fused system comprising both visual and audio cues, proved to be superior toboth audio-only and video-only systems.

  • 70. James Emmanuel Roy, Muggalla
    et al.
    Garimella, Pradeep
    Evaluation of Parallel Programming Standards For  Embedded High Performance Computing2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this project is to evaluate parallel programming standards for embedded high performance computing. There is a huge demand for high computational speed and performance in the present radar signal processing, so more processors are needed to get enough performance. One way of getting high performance is by dividing the work on multiple processors. At the same time, it has to get low communication overhead and good speedup. This has been done by using parallel computing languages such as OpenMP and MPI.We use these parallel programming languages on radar signal benchmark which is similar to many tasks in radar signal processing. For running OpenMP, a shared memory system SUNFIRE E2900 is used and for MPI, a SUNFIRE E2900, containing 8 nodes which uses SUN HPC cluster tools v5 is used. The OpenMP program shows pretty good speedup up to 5 processors, there after an increase in communication overhead is observed. MPI has shown low communication overhead at the beginning but got decreases when the numbers of processors were increased. Both OpenMP and MPI show similar aspects, at certain limit as the number of processors are increased there is decreasing trend in efficiency and increase in communication overhead. According to our results, OpenMP is a relatively easy to use program when compared to MPI. When using MPI it is up to the programmer to make explicit calls in order to parallelize.

  • 71.
    Johansson, Lars-Olof
    Växjö University.
    Visualization/graphical modeling as a supporting tool in organizational development activities: an action oriented approach2008Licentiate thesis, comprehensive summary (Other academic)
  • 72.
    Johnsson, Dennis
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Bengtsson, Jerker
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Two-level Reconfigurable Architecture for High-Performance Signal Processing2004In: ERSA'04, The 2004 International Conference on Engineering of Reconfigurable Systems and Algorithms: The 2004 International MultiConference in Computer Science and Computer Engineering / [ed] Toomas P. Plaks, Arthens: CSREA Press, 2004, p. 177-183Conference paper (Refereed)
    Abstract [en]

    High speed signal processing is often performed as a pipeline of functions on streams or blocks of data. In order to obtain both flexibility and performance, parallel, reconfigurable array structures are suitable for such processing. The array topology can be used both on the micro and macro-levels, i.e. both when mapping a function on a fine-grained array structure and when mapping a set of functions on different nodes in a coarse-grained array. We outline an architecture on the macro-level as well as explore the use of an existing, commercial, word level reconfigurable architecture on the micro-level. We implement an FFT algorithm in order to determine how much of the available resources are needed for controlling the computations. Having no program memory and instruction sequencing available, a large fraction, 70%, of the used resources is used for controlling the computations, but this is still more efficient than having statically dedicated resources for control. Data can stream through the array at maximum I/O rate, while computing FFTs. The paper also shows how pipelining of the FFT algorithm over a two-level reconfigurable array of arrays can be done in various ways, depending on the application demands.

  • 73.
    Kaiabachev, Roumen
    et al.
    Rice University, Houston, TX, USA.
    Taha, Walid
    Rice University, Houston, TX, USA.
    Zhu, Angela
    Rice University, Houston, TX, USA.
    E-FRP with Priorities2007In: EMSOFT '07: Proceedings of the Seventh ACM and IEEE International Conference on Embedded Software / [ed] Christoph M Kirsch & Reinhard Wilhelm, New York, NY: ACM Press, 2007, p. 221-230Conference paper (Other academic)
    Abstract [en]

    E-FRP is declarative language for programming resourcebounded,event-driven systems. The original high-level semanticsof E-FRP requires that each event handler executeatomically. This requirement facilitates reasoning about EFRPprograms, and therefore it is a desirable feature of thelanguage. But the original compilation strategy requiresthat each handler complete execution before another eventcan occur. This implementation choice treats all eventsequally, in that it forces the upper bound on the time neededto respond to any event to be the same. While this is acceptablefor many applications, it is often the case that someevents are more urgent than others.In this paper, we show that we can improve the compilationstrategy without altering the high-level semantics.With this new compilation strategy, we give the programmermore control over responsiveness without taking awaythe ability to reason about programs at a high level. Theprogrammer controls responsiveness by declaring prioritiesfor events, and the compilation strategy produces code thatuses preemption to enforce these priorities. We show thatthe compilation strategy enjoys the same properties as theoriginal strategy, with the only change being that the programmerreasons modulo permutations on the order of eventarrivals.

  • 74.
    Kalsyte, Zivile
    et al.
    Kaunas University of Technology, Kaunas, Lithuania.
    Verikas, Antanas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent Systems´ laboratory. Kaunas University of Technology, Kaunas, Lithuania.
    Bacauskiene, Marija
    Kaunas University of Technology, Kaunas, Lithuania.
    Gelzinis, Adas
    Kaunas University of Technology, Kaunas, Lithuania.
    A novel approach to designing an adaptive committee applied to predicting company’s future performance2013In: Expert systems with applications, ISSN 0957-4174, E-ISSN 1873-6793, Vol. 40, no 6, p. 2051-2057Article in journal (Refereed)
    Abstract [en]

    This article presents an approach to designing an adaptive, data dependent, committee of models applied to prediction of several financial attributes for assessing company's future performance. Current liabilities/Current assets, Total liabilities/Total assets, Net income/Total assets, and Operating Income/Total liabilities are the attributes used in this paper. A self-organizing map (SOM) used for data mapping and analysis enables building committees, which are specific (committee size and aggregation weights) for each SOM node. The number of basic models aggregated into a committee and the aggregation weights depend on accuracy of basic models and their ability to generalize in the vicinity of the SOM node. A random forest is used a basic model in this study. The developed technique was tested on data concerning companies from ten sectors of the healthcare industry of the United States and compared with results obtained from averaging and weighted averaging committees. The proposed adaptivity of a committee size and aggregation weights led to a statistically significant increase in prediction accuracy if compared to other types of committees. © 2012 Elsevier Ltd. All rights reserved.

  • 75. Khan, Azhar Shabbir
    et al.
    Afzal, Bilal
    MPLS VPNs with DiffServ: A QoS Performance Study2011Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    MPLS (Multiprotocol Label Switching) VPNs (Virtual private network) are new alternatives to private WANs (Wide area network). They are gaining popularity in industry day by day. Enterprise customers are moving to service providers that offer MPLS VPNs. The main reason for this shifting is the capability of MPLS VPN to provide built in security features and any-to-any connectivity. QoS (Quality of service) is the most important element for enterprise networks. Enterprise network have video, audio and data traffic over a single network infrastructure.In this thesis we will investigate QoS parameters (e.g. delay, jitter and packet loss) over MPLS VPNs environment. It will help the service providers and enterprise network customers to maintain QoS for voice, video and data traffic over MPLS VPNs environment.To achieve consistent end-to-end QoS, the service provider and the enterprise customer must work closely together and share the same policies to implement because service provider participates in customer routing in MPLS VPN environment. We will use the DiffServ (Differentiated services) QoS model over MPLS VPN network. We will use a six class model for service provider network and enterprise customer network to achieve end-to- end service quality.In the last part we will make tests of end-to-end traffic delay, jitter and packet loss. We will compare the results of delay, jitter and packet loss with and without the DiffServ QoS model in an MPLS VPNs environment. It will be clear in the results that without using DiffServ QoS model delay, jitter and packet loss are increasing as the traffic increases on the network. With a DiffServ enabled network, the increase of traffic over network will not affect delay, jitter and packet loss and provide constant level of service quality.

  • 76.
    Kontrimas, Vilius
    et al.
    Department of Information Systems, Department of Applied Electronics, Kaunas University of Technology, Kaunas, Lithuania.
    Verikas, Antanas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    The mass appraisal of the real estate by computational intelligence2011In: Applied Soft Computing, ISSN 1568-4946, E-ISSN 1872-9681, Vol. 11, no 1, p. 443-448Article in journal (Refereed)
    Abstract [en]

    Mass appraisal is the systematic appraisal of groups of properties as of a given date using standardized procedures and statistical testing. Mass appraisal is commonly used to compute real estate tax. There are three traditional real estate valuation methods: the sales comparison approach, income approach, and the cost approach. Mass appraisal models are commonly based on the sales comparison approach. The ordinary least squares (OLS) linear regression is the classical method used to build models in this approach. The method is compared with computational intelligence approaches - support vector machine (SVM) regression, multilayer perceptron (MLP), and a committee of predictors in this paper. All the three predictors are used to build a weighted data-depended committee. A self-organizing map (SOM) generating clusters of value zones is used to obtain the data-dependent aggregation weights. The experimental investigations performed using data cordially provided by the Register center of Lithuania have shown very promising results. The performance of the computational intelligence-based techniques was considerably higher than that obtained using the official real estate models of the Register center. The performance of the committee using the weights based on zones obtained from the SOM was also higher than of that exploiting the real estate value zones provided by the Register center. (C) 2009 Elsevier B.V. All rights reserved

  • 77.
    Kunze, Sebastian
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Symbolic Characterisation of Commonalities in Testing Software Product Lines2016In: 2016 9TH IEEE INTERNATIONAL CONFERENCE ON SOFTWARE TESTING, VERIFICATION AND VALIDATION (ICST), Piscataway, N.J.: IEEE , 2016, p. 387-388Conference paper (Refereed)
    Abstract [en]

    Validation and verification of Software Product Lines is particularly challenging due to the complex structure and interaction of commonalities and variabilities among products. There are several approaches to specify the structure of such commonalities and variabilities, such as the delta-oriented approach. Building upon such a structure, we propose an approach to avoid redundant analysis in Software Product Lines by extending them to semantic behavioural changes. To this end, we propose to use Differential Symbolic Execution, an automated technique for proving functional behavioural equivalence based on satisfiability modulo theories. Our proposal aims at identifying the behavioural commonalities of one software product relative to another and exploits them in order to establish an efficient model-based testing trajectory.

  • 78.
    Kunze, Sebastian
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Mostowski, Wojciech
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Varshosaz, Mahsa
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Generation of Failure Models through Automata Learning2016In: Proceedings: 2016 Workshop on Automotive Systems/Software Architectures, Los Alamitos: IEEE Computer Society, 2016, p. 22-25, article id 7484118Conference paper (Refereed)
    Abstract [en]

    In the context of the AUTO-CAAS project that deals with model-based testing techniques applied in the automotive domain, we present the preliminary ideas and results of building generalised failure models for non-conformant software components. These models are a necessary building block for our upcoming efforts to detect and analyse failure causes in automotive software built with AUTOSAR components. Concretely, we discuss how to build these generalised failure models using automata learning techniques applied to a guided model-based testing procedure of a failing component. We illustrate our preliminary findings and experiments on a simple integer queue implemented in the C programming language. © 2016 IEEE.

  • 79.
    Kuttner, Filip
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Linderson, Eric
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Idoffsson, Martin
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    AutoKaddy: en självgående golfvagnIndependent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Anders Sjöblom and Mats Larson are two golf players that have come up with a concept for a golf cart which automatically follows the player, who carries a compact GPS and Bluetooth unit enabled to communicate with a microprocessor mounted on the cart. Bluetooth is used as a wireless communication protocol and the microprocessor calculates optimal path from the recorded GPS‐data and runs the cart‐fitted engines, one for each wheel. The cart is also equipped with two push‐ buttons for user interaction. One is ON/OFF which starts and shuts‐ down the system, and PAUSE/CONTINUE which puts the cart on hold or re‐enables the following function. The cart is available to buy as a product, but with very limited steering functionality, it can only move forward. It is critical that the cart takes exactly the same route as the player and the system should not try to calculate the fastest or most efficient route because obstacles can occur.

  • 80.
    Kärral, Kenan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    3D CAD API2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 81.
    Larsson, Marcus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Metadata: En forensisk analys av Exif2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I en bild tagen med en digitalkamera kan man återfinna mängder av information om bildens ursprung och inställningar i kameran, något som benämns som Exif3data. Detta är något som kan vara av absolut intresse vid forensiska undersökningar i syfte att knyta bevismaterial till en gärningsman. I detta arbete skall ett antal frågeställningar besvaras som kan vara aktuell för en IT3 forensiker, med avseende på bilder tagna med en smartphone. Kan man styrka att en specifik enhet har tagit en specifik bild? Hur tillförlitlig är den GPS3information som kan lagras i en bild? Genom experiment och granskningar av Exif3data, kommer detta arbete ge svar på dessa frågor. Arbetet kommer också ge exempel på verktyg för att tolka Exif3 informationen. Vidare kommer arbetet även ta upp huruvida den mobila applikationen WhatsApp! väljer att radera Exif3data vid överföring av bilder mellan smartphones.

  • 82.
    Lidström, Kristoffer
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    A Spatial QoS Requirements Specification for V2V Applications2010In: IEEE Intelligent Vehicles Symposium (IV), 2010, Piscataway, NJ.: IEEE Press, 2010, p. 548-553Conference paper (Refereed)
    Abstract [en]

    Vehicle-to-vehicle wireless communication is a key component of tomorrow's cooperative safety applications. However, the wireless link is susceptible to effects such as shadowing which can cause communication failures. Such failures may in turn lead to hazardous traffic situations when safety applications cease to function. By monitoring communication QoS and adapting to changes, effects of link failure may be mitigated, however this requires a specification of the application QoS requirements. In this paper we combine the T-Window reliability QoS metric with a spatial component, allowing us to capture the dependencies between VANET QoS requirements and road geometry. The proposed representation can be used both at design-time, to characterize applications, and at run-time for QoS monitoring and adaptation purposes.

  • 83.
    Lierler, Yuliya
    et al.
    University of Nebraska, Omaha, USA.
    Taha, WalidHalmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Rice University, Houston, USA.
    Practical Aspects of Declarative Languages: 19th International Symposium, PADL 2017, Paris, France, January 16-17, 2017, Proceedings2017Conference proceedings (editor) (Refereed)
    Abstract [en]

    The proceedings contain 14 papers. The special focus in this conference is on Practical Aspects of Declarative Languages. The topics include: Eliminating irrelevant non determinism in functional logic programs; canonicalizing high-level constructs in picat; integrating answer set programming with object-oriented languages; extending answer set programs with interpreted functions as first-class citizens; lowering the learning curve for declarative programming; overlapping patterns for property-based testing; Boltzmann samplers for closed simply-typed lambda terms; selection equilibria of higher-order games; principles and prototype implementation; declarative programming of full-fledged musical applications; a domain-specific language for software-defined radio; a declarative DSL for customizing ASCII art and using iterative deepening for probabilistic logic inference. © Copyright 2017 Elsevier B.V., All rights reserved

  • 84.
    Lind, Christoffer
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Green, Jonas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Ingvarsson, Thomas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Movement sensor using image correlation on a multicore platform2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to investigate the possibility to measure speed of a vehicle usingimage correlation. It was identified that a new solution of measuring the speed of a vehicle, astoday’s solution does not give the True Speed Over Ground, would open up possibilities of highprecision driving applications. It was also the intention to evaluate the performance of theproposed algorithm on a multicore platform. The study was commissioned by HalmstadUniversity.The investigation of image correlation as a method to measure speed of a vehicle was conductedby applying the proposed algorithm on a sequence of images. The result was compared toreference points in the image sequence to confirm the accuracy. The performance of the multicoreplatform was measured by counting the clock cycles it took to perform one measurement cycle ofthe algorithm.It was found out that using image correlation to measure speed has a positional accuracy of closeto a half percent. The results also revealed that one measurement cycle of the algorithm could beperformed in close to half a millisecond and the achieved parallel utilization of the multicoreplatform was close to eighty-seven percent.It was concluded that the algorithm performed well within the limit of acceptance. A conclusionabout the performance was that low execution time of a measurement cycle makes it possible toexecute the algorithm at a frequency of eighteen hundred Hertz. With a frequency that high, incombination with the camera settings proposed in the thesis, the algorithm would be able tomeasure speeds close to one thousand one hundred kilometers per hour.The authors recommend that future work should be focused on investigating the cameraparameters to be able to optimize both the memory and computational requirements of theapplication. It is also recommended to look closer at the algorithm and the possibilities ofdetecting transversal and angular changes as it would open up for other application areas,requiring more than just the speed.

  • 85.
    Lindskog, Jakob
    et al.
    Halmstad University, School of Information Technology.
    Gunnarsson, Robin
    Halmstad University, School of Information Technology.
    Databearbetning på Ringhals2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The new generation of digitalization has been ingrained into society. Algorithms and data models are controlling the news feed of social media, controlling the phone by interpreting voices and controlling the car, altogether with automonous vehicles. In the industries there is also an ongoing process where machine learning is applied to increase availability and reduce costs.

    The current paradigm for maintaining non-critical machines in the nuclear power industry is a combination of corrective maintenance and preventive maintenance. Corrective maintenance means doing repairs on the machine upon faults, preventive maintenance means doing repairs periodically. Both ways are costly because they run the risk of under- and over-maintaining the machine and therefore becoming resource-intensive. A paradigm shift is on it's way, and it's spelled Predictive Maintenance - being able to predict faults before they happen and plan maintenance thence.

    This report explores the possibilities of using LSTM and GRU to forecast potential damage on machines. This is based on data from measurements and historical issues on the machine.

  • 86.
    Lopez-Rojas, Edgar
    et al.
    NTNU, Gjøvik, Norway.
    Axelsson, Stefan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Baca, Dejan
    3M-Commerce, Ericsson AB, Karlskrona, Sweden.
    Analysis of fraud controls using the PaySim financial simulator2018In: International Journal of Simulation and Process Modelling, ISSN 1740-2123, E-ISSN 1740-2131, Vol. 13, no 4, p. 377-386Article in journal (Refereed)
    Abstract [en]

    Fraud controls for financial transactions are needed and required by law enforcement agencies to flag suspicious criminal activity. These controls, however, require deeper analysis of the effectiveness and the negative impact for the legal customers. Owing to the intrinsically private nature of financial transactions, this analysis is often performed after several months of actively using fraud controls. In this paper, we present an analysis of different fraud prevention controls on a mobile money service based on thresholds using a simulator called PaySim. PaySim uses aggregated data from a sample dataset to generate a synthetic dataset that resembles the normal operation of transactions and injects malicious behaviour. With technology frameworks such as agent-based simulation techniques, and the application of mathematical statistics, we show in this paper that the simulated data can be as prudent as the original dataset for setting optimal controls for fraud detection.

  • 87.
    Lundström, Jens
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Verikas, Antanas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Assessing print quality by machine in offset colour printing2013In: Knowledge-Based Systems, ISSN 0950-7051, E-ISSN 1872-7409, Vol. 37, p. 70-79Article in journal (Refereed)
    Abstract [en]

    Information processing steps in printing industry are highly automated, except the last one print quality assessment, which usually is a manual, tedious, and subjective procedure. This article presents a random forests-based technique for automatic print quality assessment based on objective values of several printquality attributes. Values of the attributes are obtained from soft sensors through data mining and colour image analysis. Experimental investigations have shown good correspondence between print quality evaluations obtained by the technique proposed and the average observer. (C) 2012 Elsevier B.V. All rights reserved.

  • 88.
    Lundström, Jens
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Verikas, Antanas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Detecting Halftone Dots for Offset Print Quality Assessment Using Soft Computing2010In: 2010 IEEE International Conference on Fuzzy Systems (FUZZ), Piscataway, NJ: IEEE Press, 2010, p. 1145-1151Conference paper (Refereed)
    Abstract [en]

    Nowadays in printing industry most of information processing steps are highly automated, except the last one–print quality assessment and control. We present a way to assess one important aspect of print quality, namely the distortion of halftone dots printed colour pictures are made of. The problem is formulated as assessing the distortion of circles detected in microscale images of halftone dot areas. In this paper several known circle detection techniques are explored in terms of accuracy and robustness. We also present a new circle detection technique based on the fuzzy Hough transform (FHT) extended with k-means clustering for detecting positions of accumulator peaks and with an optional fine-tuning step implemented through unsupervised learning. Prior knowledge about the approximate positions and radii of the circles is utilized in the algorithm. Compared to FHT the proposed technique is shown to increase the estimation accuracy of the position and size of detected circles. The techniques are investigated using synthetic and natural images.

  • 89.
    Lundström, Jens
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent Systems´ laboratory.
    Verikas, Antanas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent Systems´ laboratory. Kaunas University of Technology, Kaunas, Lithuania.
    Tullander, E.
    Hylte Mill, Hyltebruk, Sweden.
    Larsson, B.
    V-TAB, Hisingsbacka, Sweden.
    Assessing, exploring, and monitoring quality of offset colour prints2013In: Measurement, ISSN 0263-2241, E-ISSN 1873-412X, Vol. 46, no 4, p. 1427-1441Article in journal (Refereed)
    Abstract [en]

    Variations in offset print quality relate to numerous parameters of printing press and paper. To maintain a constant high print quality press operators need to assess, explore and monitor quality of prints. Today assessment is mainly done manually. This paper presents a novel system for assessing and predicting values of print quality attributes, where the adopted, random forests (RFs)-based, modeling approach also allows quantifying the influence of different paper and press parameters on print quality. In contrast to other print quality assessment systems the proposed system utilises common, simple print marks known as double grey-bars. Novel virtual sensors assessing print quality attributes using images of double grey-bars are presented. The inferred influence of paper and printing press parameters on quality of colour prints shows clear relation with known print quality conditions. Thorough analysis and categorisation of related work is also given in the paper. (C) 2012 Elsevier Ltd. All rights reserved.

  • 90.
    Malec, Jacek
    et al.
    Department of Computer Science, Lund University, Lund, Sweden.
    Nowaczyk, Sławomir
    Department of Computer Science, Lund University, Lund, Sweden.
    Deduction and Exploratory Assessment of Partial Plans2005In: Proceedings of the IJCAI 2005 Workshop on Planning and Learning in A Priori Unknown or Dynamic Domains: the International Joint Conference on Artificial Intelligence, IJCAI / [ed] Vadim Bulitko, Sven Koenig, Edinburgh, 2005, p. 117-124Conference paper (Refereed)
    Abstract [en]

    In this paper we present a preliminary investigation of rational agents who, aware of their own limited mental resources, use learning to augment their reasoning. In our approach an agent creates and deductively reasons about possible plans of actions ,but — aware of the fact that finding complete plans is in many cases intractable — it executes partial plans which look promising. By doing so, it can acquire new knowledge from results of performed actions, which allows it to plan further into the future in a more effective way. We describe a possible application of Inductive Logic Programming to learn which of such partial plans are most likely to lead to reaching the goal. We also discuss how one can use ILP framework for generalising partial plans, thus allowing an agent to discover, after a number of episodes, a complete plan — or at least a good approximation of it.

  • 91.
    Mashad Nemati, Hassan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Data-Driven Methods for Reliability Evaluation of Power Cables in Smart Distribution Grids2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This research aims to develop data-driven methods that automatically exploit historical data in smart distribution grids for reliability evaluation, i.e., analyzing frequency of failures, and modeling components’ lifetime. The results enable power distribution companies to change from reactive maintenance to predictive maintenance by deriving benefits from historical data. In particular, the data is exploited for two purposes: (a) failure pattern discovery, and (b) reliability evaluation of power cables. To analyze failure characteristics it is important to discover which failures share common features, e.g., if there are any types of failures that happen mostly in certain parts of the grid or at certain times. This analysis provides information about correlation between different features and identifying the most vulnerable components. In this case, we applied statistical analysis and association rules to discover failure patterns. Furthermore, we propose an easy-to-understand visualization of the correlations between different factors representing failures by using an approximated Bayesian network. We show that the Bayesian Network constructed based on the interesting rules of two items is a good approximation of the real dataset. The main focus of reliability evaluation is on failure rate estimation and reliability ranking. In case of power cables, the limited amount of recorded events makes it difficult to perform failure rate modeling, i.e., estimating the function that describes changes in the rate of failure depending on age. Therefore, we propose a method for interpreting the results of goodness-of-fit measures with confidence intervals, estimated using synthetic data. To perform reliability ranking of power cables, in addition to the age of cables, we consider other factors. Then, we use the Cox proportional hazard model (PHM) to assess the impact of the factors and calculate the failure rate of each individual cable. In reliability evaluation, it is important to consider the fact that power cables are repairable components. We show that the conclusions about different factors in PHM and cables ranking will be misleading if one considers the cables as non-repairable components. The developed methods of (a) are applied on data from Halmstad Energi och Miljö (HEM Nät), Öresundskraft, Göteborg Energy, and Växjö Energy, four different distribution system operators in Sweden. The developed methods of (b) are applied on data from HEM Nät.

  • 92.
    Mashad Nemati, Hassan
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Sant´Anna, Anita
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Bayesian Network Representation of Meaningful Patterns in Electricity Distribution Grids2016In: 2016 IEEE International Energy Conference (ENERGYCON), 2016Conference paper (Refereed)
    Abstract [en]

    The diversity of components in electricity distribution grids makes it impossible, or at least very expensive, to deploy monitoring and fault diagnostics to every individual element. Therefore, power distribution companies are looking for cheap and reliable approaches that can help them to estimate the condition of their assets and to predict the when and where the faults may occur. In this paper we propose a simplified representation of failure patterns within historical faults database, which facilitates visualization of association rules using Bayesian Networks. Our approach is based on exploring the failure history and detecting correlations between different features available in those records. We show that a small subset of the most interesting rules is enough to obtain a good and sufficiently accurate approximation of the original dataset. A Bayesian Network created from those rules can serve as an easy to understand visualization of the most relevant failure patterns. In addition, by varying the threshold values of support and confidence that we consider interesting, we are able to control the tradeoff between accuracy of the model and its complexity in an intuitive way. © 2016 IEEE

  • 93.
    Mattsson, Fredrik
    et al.
    Halmstad University, School of Information Technology.
    Gustafsson, Anton
    Halmstad University, School of Information Technology.
    Optimize Ranking System With Machine Learning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates how recommendation systems has been used and can be used with the help of different machine learning algorithms. Algorithms used and presented are decision tree, random forest and singular-value decomposition(SVD). Together with Tingstad, we have tried to implement the SVD function on their recommendation engine in order to enhance the recommendation given. A trivial presentation on how the algorithms work. General information about machine learning and how we tried to implement it with Tingstad’s data. Implementations with Netflix’s and Movielens open-source dataset was done, estimated with RMSE and MAE.

  • 94.
    Mazur, Milosz
    Halmstad University, School of Information Technology.
    Behavior Trees Evolution by Means of Genetic Programming2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Behavior Trees are a method for AI programming that consists of a tree of hierarchical nodes controlling the flow of agent's decision making. They have proven, while being a pretty straightforward means to implement an AI, to be incredibly powerful way of obtaining autonomous agents, both due to a fact that the development can be iterable (one can start with implementing simple behavior and gradually improve the tree by adding and modifying nodes and branches) and allowing for, so to say, ``fallback tactics'', should the currently executed action fail. Born in the game industry, they have since gained fair amount of popularity in other domains, including robotics.Evolutionary algorithms, largely popularized by John Holland, have been adapted for use in a vast variety of different problems, including optimization issues and decision handling, often through introducing serious changes to both the algorithm structure and data structures used. Arguably, one of the most valuable modifications was Genetic Programming, popularized through works of John Koza.

    This thesis documents the work on combining Behavior Trees and Genetic Programming in order to study and observe cooperative and adversative behaviors between agents controlled by genetically generated Behavior Trees. Evolving two kinds of agents in two contrasting scenarios, this thesis focuses on feasibility of selfishness versus utilitarian behaviors and their evolution. After defining what constitutes a success for each case, we attempt to compare the results from respective scenarios to see which behavior type is profitable to exhibit.

  • 95.
    Mohaqeqi, Morteza
    et al.
    Uppsala University, Uppsala, Sweden.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Towards an Approximate Conformance Relation for Hybrid I/O Automata2016In: Proceedings of the The First Workshop on Verification and Validation of Cyber-Physical Systems / [ed] Mehdi Kargahi & Ashutosh Trivedi, Sydney: Open Publishing Association , 2016, Vol. 232, p. 53-64Conference paper (Refereed)
    Abstract [en]

    Several notions of conformance have been proposed for checking the behavior of cyber-physical systems against their hybrid systems models. In this paper, we explore the initial idea of a notion of approximate conformance that allows for comparison of both observable discrete actions and (sampled) continuous trajectories. As such, this notion will consolidate two earlier notions, namely the notion of Hybrid Input-Output Conformance (HIOCO) by M. van Osch and the notion of Hybrid Conformance by H. Abbas and G.E. Fainekos. We prove that our proposed notion of conformance satisfies a semi-transitivity property, which makes it suitable for a step-wise proof of conformance or refinement.

  • 96.
    Mohaqeqi, Morteza
    et al.
    School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Taha, Walid
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Rice University, Houston, Texas, USA.
    Conformance Testing of Cyber-Physical Systems: A Comparative Study2014In: Proceedings of the 14th International Workshop on Automated Verification of Critical Systems (AVoCS 2014) / [ed] Marieke Huisman, Jaco van de Pol, Tiziana Margaria, Julia Padberg & Gabriele Taentzer, Berlin: European Association of Software Science and Technology , 2014Conference paper (Refereed)
    Abstract [en]

    For systematic and automatic testing of cyber-physical systems, in which a set of test cases is generated based on a formal specification, a number of notions of conformance testing have been proposed. In this paper, we review two existing theories of conformance testing for cyber-physical systems and compare them. We point out their fundamental differences, and prove under which assumptions they coincide.

  • 97.
    Mostowski, Wojciech
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Model-based fault injection for testing gray-box systems2019In: The Journal of logical and algebraic methods in programming, ISSN 2352-2208, E-ISSN 2352-2216, Vol. 103, p. 31-45Article in journal (Refereed)
    Abstract [en]

    Motivated by applications in the automotive domain, particularly the Autosar basic software standard, we present a technique to improve model-based testing by allowing model-level fault injections. These models are plugged into a larger system as executable components to test it for general tolerance to slightly varying, possibly faulty components or library implementations. Such model execution is possible through applying an automated mocking mechanism and model cross-referencing. Systematic modelling and testing is possible by having comprehensive fault models which both simulate faults and guide the model-based testing procedure towards quicker discovery of these faults. We show the principles of our method on an illustrative example and discuss how it is implemented in a commercial model-based testing tool QuickCheck and applied to a more realistic case study. More generally, this work explores multi-purpose (or meta) modelling – an approach where one parametric model is used for different test targets, like functional testing or safety testing.

  • 98.
    Mostowski, Wojciech
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Verifying Java Card Programs2016In: Deductive Software Verification – The KeY Book: From Theory to Practice / [ed] Wolfgang Ahrendt, Bernhard Beckert, Richard Bubel, Reiner Hähnle, Peter H. Schmitt & Mattias Ulbrich, Heidelberg: Springer, 2016, p. 353-380Chapter in book (Other academic)
    Abstract [en]

    This chapter presents the extension of KeY and JavaDL to handle a particular and peculiar dialect of Java, namely Java Card, for programming smart cards. The necessary extensions to the logic and the specification language are discussed, followed by a number of small case studies. The chapter is concluded with applications of the ideas presented here to on-going and future research, in particular in reasoning about concurrent Java programs. © Springer International Publishing AG 2016

  • 99.
    Mostowski, Wojciech
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Arts, Thomas
    QuviQ AB, Göteborg, Sweden.
    Hughes, John
    Chalmers University of Technology, Göteborg, Sweden & QuviQ AB, Göteborg, Sweden.
    Modelling of Autosar Libraries for Large Scale Testing2017In: 2nd Workshop on Models for Formal Analysis of Real Systems (MARS 2017) / [ed] Holger Hermanns & Peter Höfner, 2017, Vol. 244, p. 184-199Conference paper (Refereed)
    Abstract [en]

    We demonstrate a specific method and technology for model-based testing of large software projects with the QuickCheck tool using property-based specifications. Our specifications are very precise, state-full models of the software under test (SUT). In our approach we define (a) formal descriptions of valid function call sequences (public API), (b) postconditions that check the validity of each call, and (c) call-out specifications that define and validate external system interactions (SUT calling external API). The QuickCheck tool automatically generates and executes tests from these specifications. Commercially, this method and tool have been used to test large parts of the industrially developed automotive libraries based on the Autosar standard. In this paper, we exemplify our approach with a circular buffer specified by Autosar, to demonstrate the capabilities of the model-based testing method of QuickCheck. Our example is small compared to the commercial QuickCheck models, but faithfully addresses many of the same challenges. © W. Mostowski, T. Arts, J. Hughes.

  • 100.
    Mostowski, Wojciech
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ulbrich, Mattias
    Karlsruhe Institute of Technology, Karlsruhe, Germany.
    Dynamic Dispatch for Method Contracts Through Abstract Predicates2016In: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 9800, p. 238-267Article in journal (Refereed)
    Abstract [en]

    Dynamic method dispatch is a core feature of object-oriented programming by which the executed implementation for a polymorphic method is only chosen at runtime. In this paper, we present a specification and verification methodology which extends the concept of dynamic dispatch to design-by-contract specifications.

    The formal specification language JML has only rudimentary means for polymorphic abstraction in expressions. We promote these to fully flexible specification-only query methods called model methods that can, like ordinary methods, be overridden to give specifications a new semantics in subclasses in a transparent and modular fashion. Moreover, we allow them to refer to more than one program state which give us the possibility to fully abstract and encapsulate two-state specification contexts, i.e., history constraints and method postconditions. Finally, we provide an elegant and flexible mechanism to specify restrictions on specifications in subtypes. Thus behavioural subtyping can be enforced, yet it still allows for other specification paradigms.

    We provide the semantics for model methods by giving a translation into a first order logic and according proof obligations. We fully implemented this framework in the KeY program verifier and successfully verified relevant examples. We have also implemented an extension to KeY to support permission-based verification of concurrent Java programs. In this context model methods provide a modular specification method to treat code synchronisation through API methods. © The Author(s) 2016.

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