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  • 1.
    Abbas, Taimoor
    et al.
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    Sjöberg, Katrin
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Kåredal, Johan
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    Tufvesson, Fredrik
    Lund Univ, Elect & Informat Technol Dept, S-22100 Lund, Sweden..
    A Measurement Based Shadow Fading Model for Vehicle-to-Vehicle Network Simulations2015In: International Journal of Antennas and Propagation, ISSN 1687-5869, E-ISSN 1687-5877, article id 190607Article in journal (Refereed)
    Abstract [en]

    The vehicle-to-vehicle (V2V) propagation channel has significant implications on the design and performance of novel communication protocols for vehicular ad hoc networks (VANETs). Extensive research efforts have been made to develop V2V channel models to be implemented in advanced VANET system simulators for performance evaluation. The impact of shadowing caused by other vehicles has, however, largely been neglected in most of the models, as well as in the system simulations. In this paper we present a shadow fading model targeting system simulations based on real measurements performed in urban and highway scenarios. The measurement data is separated into three categories, line-of-sight (LOS), obstructed line-of-sight (OLOS) by vehicles, and non-line-of-sight due to buildings, with the help of video information recorded during the measurements. It is observed that vehicles obstructing the LOS induce an additional average attenuation of about 10 dB in the received signal power. An approach to incorporate the LOS/OLOS model into existing VANET simulators is also provided. Finally, system level VANET simulation results are presented, showing the difference between the LOS/OLOS model and a channel model based on Nakagami-m fading.

  • 2.
    Abdulrazzaq, Mohammed
    et al.
    Halmstad University, School of Information Technology.
    Wei, Yuan
    Halmstad University, School of Information Technology.
    Industrial Control System (ICS) Network Asset Identification and Risk Management2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Setting against the significant background of Industrial 4.0, the Industrial Control System (ICS) accelerates and enriches the upgrade the existing production infrastructure. To make the infrastructures “smart”, huge parts of manual operations have been automated in this upgrade and more importantly, the isolated controlled processes have been connected through ICS. This has also raised the issues in asset management and security concerns. Being the starting point of securing the ICS, the asset identification is, nevertheless, first dealt by exploring the definition of assets in the ICS domain due to insufficient documentation and followed by the introduction of ICS constituents and their statuses in the whole network. When the definition is clear, a well-received categorization of assets in the ICS domain is introduced, while mapping out their important attributes and their significance relating the core of service they perform. To effectively tackle the ever-increasing amount of assets, identification approaches are compared and a case study was performed to test the effectiveness of two open source software. Apart from the identification part, this thesis describes a framework for efficient asset management from CRR. The four cyclic modules proposed give an overview on how the asset management should be managed according the dynamics of the assets in the production environment.

  • 3.
    Aceto, Luca
    et al.
    ICE-TCS, School of Computer Science, Reykjavik University, Reykjavik, Iceland.
    Goriac, Eugen-Ioan
    ICE-TCS, School of Computer Science, Reykjavik University, Reykjavik, Iceland.
    Ingolfsdottir, Anna
    ICE-TCS, School of Computer Science, Reykjavik University, Reykjavik, Iceland.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Reniers, Michel A.
    Department of Mechanical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
    Exploiting Algebraic Laws to Improve Mechanized Axiomatizations2013In: Algebra and Coalgebra in Computer Science: 5th International Conference, Calco 2013, Warsaw, Poland, September 2013, Proceedings, Berlin: Springer Berlin/Heidelberg, 2013, p. 36-50Conference paper (Refereed)
    Abstract [en]

    In the field of structural operational semantics (SOS), there have been several proposals both for syntactic rule formats guaranteeing the validity of algebraic laws, and for algorithms for automatically generating ground-complete axiomatizations. However, there has been no synergy between these two types of results. This paper takes the first steps in marrying these two areas of research in the meta-theory of SOS and shows that taking algebraic laws into account in the mechanical generation of axiomatizations results in simpler axiomatizations. The proposed theory is applied to a paradigmatic example from the literature, showing that, in this case, the generated axiomatization coincides with a classic hand-crafted one. © 2013 Springer-Verlag Berlin Heidelberg.

  • 4.
    Adam, Rania E.
    et al.
    Department of Sciences and Technology, Linköping University, Norrköping, Sweden.
    Chalangar, Ebrahim
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). Department of Sciences and Technology, Linköping University, Norrköping, Sweden.
    Pirhashemi, Mahsa
    Department of Chemistry, Faculty of Sciences, University of Mohaghegh Ardabili, Ardabil, Iran.
    Pozina, Galia
    Department of Physics, Chemistry, and Biology (IFM), Linköping University, Linköping, Sweden.
    Liu, Xianjie
    Department of Physics, Chemistry, and Biology (IFM), Linköping University, Linköping, Sweden.
    Palisaitis, Justinas
    Department of Physics, Chemistry, and Biology (IFM), Linköping University, Linköping, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). Department of Sciences and Technology, Linköping University, Norrköping, Sweden & Solid State Physics and NanoLund, Lund University, Lund, Sweden.
    Willander, Magnus
    Department of Sciences and Technology, Linköping University, Norrköping, Sweden.
    Nur, Omer
    Department of Sciences and Technology, Linköping University, Norrköping, Sweden.
    Graphene-based plasmonic nanocomposites for highly enhanced solar-driven photocatalytic activities2019In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, no 52, p. 30585-30598Article in journal (Refereed)
    Abstract [en]

    High-efficiency photocatalysts are crucial for the removal of organic pollutants and environmental sustainability. In the present work, we report on a new low-temperature hydrothermal chemical method, assisted by ultrasonication, to synthesize disruptive plasmonic ZnO/graphene/Ag/AgI nanocomposites for solar-driven photocatalysis. The plasmonic nanocomposites were investigated by a wide range of characterization techniques, confirming successful formation of photocatalysts with excellent degradation efficiency. Using Congo red as a model dye molecule, our experimental results demonstrated a photocatalytic reactivity exceeding 90% efficiency after one hour simulated solar irradiation. The significantly enhanced degradation efficiency is attributed to improved electronic properties of the nanocomposites by hybridization of the graphene and to the addition of Ag/AgI which generates a strong surface plasmon resonance effect in the metallic silver further improving the photocatalytic activity and stability under solar irradiation. Scavenger experiments suggest that superoxide and hydroxyl radicals are responsible for the photodegradation of Congo red. Our findings are important for the fundamental understanding of the photocatalytic mechanism of ZnO/graphene/Ag/AgI nanocomposites and can lead to further development of novel efficient photocatalyst materials. © 2019 Elsevier B.V.

  • 5.
    Adekolu, Adekunle Matthew
    et al.
    Halmstad University, School of Information Technology.
    Chen, Lei
    Halmstad University, School of Information Technology.
    A Simple Approach to Develop a Parental Control via a Monitoring Home Network2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis explains how a simple parental control can be developed. The system aims to limit kids’ activities rather than entirely restrict those activities. However, current solutions are applying some filtering methods that prevent kids from playing games. In order to overcome this issue, this thesis presents a simple approach to implement a cost-effective parental control using low-cost hardware devices and open source applications.The main advantage of the suggested method is that it can be used without installing any additional software and gives parents general information about their kids' activities on the internet without preventing kids from playing online games.

  • 6.
    Aein, Mohamad Javad
    et al.
    Department for Computational Neuroscience at the Bernstein Center Göttingen (Inst. of Physics 3) & Leibniz Science Campus for Primate Cognition, Georg-August-Universität Göttingen, Göttingen, Germany.
    Aksoy, Eren
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Wörgötter, Florentin
    Department for Computational Neuroscience at the Bernstein Center Göttingen (Inst. of Physics 3) & Leibniz Science Campus for Primate Cognition, Georg-August-Universität Göttingen, Göttingen, Germany.
    Internet Provisioning in VANETs: Performance Modeling of Drive-Thru Scenarios2019In: The international journal of robotics research, ISSN 0278-3649, E-ISSN 1741-3176, Vol. 38, no 8, p. 910-934Article in journal (Refereed)
    Abstract [en]

    Drive-thru-Internet is a scenario in cooperative intelligent transportation systems (C-ITSs), where a road-side unit (RSU) provides multimedia services to vehicles that pass by. Performance of the drive-thru-Internet depends on various factors, including data traffic intensity, vehicle traffic density, and radio-link quality within the coverage area of the RSU, and must be evaluated at the stage of system design in order to fulfill the quality-of-service requirements of the customers in C-ITS. In this paper, we present an analytical framework that models downlink traffic in a drive-thru-Internet scenario by means of a multidimensional Markov process: the packet arrivals in the RSU buffer constitute Poisson processes and the transmission times are exponentially distributed. Taking into account the state space explosion problem associated with multidimensional Markov processes, we use iterative perturbation techniques to calculate the stationary distribution of the Markov chain. Our numerical results reveal that the proposed approach yields accurate estimates of various performance metrics, such as the mean queue content and the mean packet delay for a wide range of workloads. © 2019 IEEE.

  • 7.
    Aerts, Arend
    et al.
    Control Systems Technology Group, Eindhoven University of Technology, Eindhoven, The Netherlands.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Reniers, Michel A.
    Control Systems Technology Group, Eindhoven University of Technology, Eindhoven, The Netherlands.
    A Tool Prototype for Model-Based Testing of Cyber-Physical Systems2015In: Theoretical Aspects of Computing – ICTAC 2015: 12th International Colloquium Cali, Colombia, October 29–31, 2015, Proceedings / [ed] Martin Leucker, Camilo Rueda, and Frank D. Valencia, Cham: Springer, 2015, Vol. 9399, p. 563-572Conference paper (Refereed)
    Abstract [en]

    We report on a tool prototype for model-based testing of cyber-physical systems. Our starting point is a hybrid-system model specified in a domain-specific language called Acumen. Our prototype tool is implemented in Matlab and covers three stages of model-based testing, namely, test-case generation, test-case execution, and conformance analysis. We have applied our implementation to a number of typical examples of cyber-physical systems in order to analyze its applicability. In this paper, we report on the result of applying the prototype tool on a DC-DC boost converter. © Springer International Publishing Switzerland 2015

  • 8.
    Aerts, Arend
    et al.
    Eindhoven University of Technology, Eindhoven, The Netherlands.
    Reniers, Michel A.
    Eindhoven University of Technology, Eindhoven, The Netherlands.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Model-Based Testing of Cyber-Physical Systems2016In: Cyber-Physical Systems: Foundations, Principles and Applications / [ed] H. Song, D.B. Rawat, S. Jeschke, and Ch. Brecher, Saint Louis: Elsevier, 2016, p. 287-304Chapter in book (Refereed)
    Abstract [en]

    Cyber-physical systems (CPSs) are the result of the integration of connected computer systems with the physical world. They feature complex interactions that go beyond traditional communication schemes and protocols in computer systems. One distinguished feature of such complex interactions is the tight coupling between discrete and continuous interactions, captured by hybrid system models.

    Due to the complexity of CPSs, providing rigorous and model-based analysis methods and tools for verifying correctness of such systems is of the utmost importance. Model-based testing (MBT) is one such verification technique that can be used for checking the conformance of an implementation of a system to its specification (model).

    In this chapter, we first review the main concepts and techniques in MBT. Subsequently, we review the most common modeling formalisms for CPSs, with focus on hybrid system models. Subsequently, we provide a brief overview of conformance relations and conformance testing techniques for CPSs. © 2017 Elsevier Inc. All rights reserved.

  • 9.
    Agelis, Sacki
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Reconfigurable Optical Interconnection Networks for High-Performance Embedded2005Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In embedded computer and communication system the capacity demand for interconnection networks is increasing continuously in order to achieve high-performance systems. Recent breakthroughs show that by using reconfigurability inside a single chip substantial performance gains can be added. However, in this thesis the focus is on system level reconfigurability (between chips or modules) and the performance gains that potentially can be achieved by having support for runtime reconfigurability on the system level.This thesis addresses the field of runtime system level reconfigurability with the use of optics in switches and routers for data- and telecommunications, and in multi-processor systems used for embedded signal processing. Several reconfigurable systems for switching and routing with support to adapt for asymmetric traffic patterns are proposed and compared to identify how design choices affect flexibility, performance etc. The proposed solutions are characterized by their multistage optical interconnection networks with reconfigurable shuffle patterns, where the reconfigurability is provided by micro-optical-electrical mechanical systems. More specifically, application-specific bottlenecks can be resolved by reconfiguring the interconnection network according to the current application demands. The benefits of the architectural solutions are confirmed by simulations that clearly show that the architectures can achieve high performance for both symmetric application characteristics and for several classes of asymmetric application characteristics. The final architectural solution is characterized by electronic packet-switches interconnected through an optical backplane, which is reconfigurable. Moreover, the thesis presents how several signal processing applications can be mapped to run concurrently in a time-shared scheme on a single reconfigurable multi-processor system that has high flexibility to adapt for the application currently at hand. The interconnection network is then adapted (reconfigured) according to the demands of the currently executed application in each time instance. The analysis shows that it is feasible to build such a system with today’s components.

  • 10.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Jacobsson, Sofia
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Alping, Arne
    Ericsson Microwave Systems, Mölndal, Sweden.
    Ligander, Per
    Ericsson Microwave Systems, Mölndal, Sweden.
    Modular interconnection system for optical PCB and backplane communication2002In: Parallel and Distributed Processing Symposium., Proceedings International, IPDPS 2002, Abstracts and CD-ROM, Los Alamitos, Calif.: IEEE Press, 2002, p. 245-250Conference paper (Refereed)
    Abstract [en]

    This paper presents a way of building modular systems with a powerful optical interconnection network. Each module, placed on a Printed Circuit Board (PCB), has a generic optical communication interface with a simple electronic router. Together with optical switching using micro-electromechanical system (MEMS) technology, packet switching over reconfigurable topologies is possible. The interconnection system gives the possibility to integrate electronics with optics without changing existing PCB technology. Great interest from industry is therefore expected and the cost advantages are several: reuse of module designs, module upgrades without changing the PCB, low-cost conventional PCB technology, etc. In the version described in this paper, the interconnection system has 48 bidirectional optical channels for intra-PCB communication on each board. For inter-PCB communication, a backplane with 192 bidirectional optical channels supports communication between twelve PCBs. With 2.5 Gbit/s per optical channel in each direction, the aggregated intra-PCB bit rate is 120 Gbit/s full duplex (on each PCB) while the aggregated inter-PCB bit rate is 480 Gbit/s full duplex. A case study shows the feasibility of the interconnection system in a parallel processing system for radar signal processing.

  • 11.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Optoelectronic router with a reconfigurable shuffle network based on micro-optoelectromechanical systems2004In: Journal of Optical Networking, ISSN 1536-5379, Vol. 4, no 1, p. 1-10Article in journal (Refereed)
    Abstract [en]

    An optoelectronic router with a shuffle exchange network is presented and enhanced by the addition of micro-optoelectromechanical systems (MOEMS) in the network to add the ability to reconfigure the shuffle network. The MOEMS described here are fully connected any-to-any crossbar switches. The added reconfigurability provides the opportunity to adapt the system to different common application characteristics. Two representative application models are described: The first has symmetric properties, and the second has asymmetric properties. The router system is simulated with the specified applications and an analysis of the results is carried out. By use of MOEMS in the optical network, and thus reconfigurability, greater than 50% increased throughput performance and decreased average packet delay are obtained for the given application. Network congestion is avoided throughout the system if reconfigurability is used.

  • 12.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Optoelectronic router with MOEMS–based reconfigurable shuffle network2004Conference paper (Refereed)
  • 13.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Reconfigurable optical interconnection system supporting concurrent application-specific parallel computing2005In: 17th Symposium on Computer Architecture and High Performance Computing: SBAC-PAD 2005 : proceedings : 24-27 October, 2005, Rio de Janeiro, PR, Brazil / [ed] Claudio L. Amorim, Washington, DC, USA: IEEE Computer Society, 2005, p. 44-51Conference paper (Refereed)
    Abstract [en]

    Application specific architectures are highly desirable in embedded parallel computing systems at the same time as designers strive for using one embedded parallel computing platform for several applications. If this can be achieved, the cost can be decreased in comparison to using several different embedded parallel computing systems. This paper presents a novel approach of running several high-performance applications concurrently on one single parallel computing system. By using a reconfigurable backplane interconnection system, the applications can be run efficiently with high network flexibility since the interconnect network can be adapted to fit the application that is being processed for the moment. More precisely, this paper investigates how the space time adaptive processing (STAP) radar algorithm and the stripmap synthetic aperture radar (SAR) algorithm can be mapped on a multi-cluster processing system with a reconfigurable optical interconnection system realized by a micro-optical-electrical mechanical system (MOEMS) crossbars. The paper describes the reconfigurable platform, the two algorithms and how they individually can be mapped on the targeted multiprocessor system. It is also described how these two applications can be mapped simultaneously on the optical reconfigurable platform. Implications and requirements on communication bandwidth and processor performance in different critical points of the two applications are presented. The results of the analysis show that an implementation is feasible with today's MOEMS technology, and that the two applications can be successfully run in a time-sharing scheme, both at the processing side and at the access for interconnection bandwidth.

  • 14.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    System-Level Runtime Reconfigurablity - Optical Interconnection Networks for Switching Applications2004In: Proceedings of the International Conference on Engineering of Reconfigurable Systems and Algorithms, ERSA'04 / [ed] Toomas P Plaks & M Gokhale, Athens, USA: CSREA Press, 2004, p. 155-162Conference paper (Refereed)
    Abstract [en]

    The performance requirements on data and telecommunication switches and routers are continuously increasing and it is evident that new ideas and architectures must come to light to satisfy these new demands. In this paper, a runtime reconfigurable modular design approach is presented, using state-of-the-art microoptical-electrical mechanical system (MOEMS) components. The paper introduces a novel field of reconfigurability, where reconfiguration is made on the system level instead of, e.g. fine-granularity reconfigurable logic. Different reconfigurable system solutions with support to adapt for asymmetric traffic patterns are proposed and compared to see how design choices affect flexibility, performance etc. The proposed solutions are characterized by their multistage networks with reconfigurable shuffle patterns.

  • 15.
    Agelis, Sacki
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Visualizing the Potential of Reconfigurable Shuffle-Patterns in Optoelectronic Routers by the Use of MOEMS2004In: Proceedings of the IASTED International Conference Communication Systems and Networks / [ed] Salvador C.E.P., Calgary, Canada: ACTA Press, 2004, p. 148-154Conference paper (Refereed)
    Abstract [en]

    A reconfigurable high performance multistage router architecture is presented and simulated. The router backbone network is an optical shuffle exchange network that has the power of reconfigurability through the use of micro-optical-electrical mechanical systems (MOEMS). The router is subjected to different application classes. The application classes have different characteristics in terms of symmetric/asymmetric traffic properties. We compare our reconfigurable shuffle-pattern for all three application classes for the specified router architecture.

  • 16.
    Aghaeipour, Mahtab
    et al.
    Lund University, Lund, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab. Lund University, Lund, Sweden.
    Enhanced broadband absorption in nanowire arrays with integrated Bragg reflectors2018In: Nanophotonics, E-ISSN 2192-8614, Vol. 7, no 5, p. 819-825Article in journal (Refereed)
    Abstract [en]

    A near-unity unselective absorption spectrum is desirable for high-performance photovoltaics. Nanowire arrays are promising candidates for efficient solar cells due to nanophotonic absorption resonances in the solar spectrum. The absorption spectra, however, display undesired dips between the resonance peaks. To achieve improved unselective broadband absorption, we propose to enclose distributed Bragg reflectors (DBRs) in the bottom and top parts of indium phosphide (InP) nanowires, respectively. We theoretically show that by enclosing only two periods of In0.56Ga0.44As/InPDBRs, an unselective 78% absorption efficiency (72% for nanowires without DBRs)is obtained at normal incidence in the spectral range from 300 nm to 920 nm. Under oblique light incidence, the absorption efficiency is enhanced up to about 85% at an incidence angle of 50º. By increasing the number of DBR periods from two to five, the absorption efficiency is further enhanced up to 95% at normal incidence. In this work we calculated optical spectra for InP nanowires, but the results are expected to be valid for other direct band gap III-V semiconductor materials. We believe that our proposed idea of integrating DBRs in nanowires offers great potential for high-performance photovoltaic applications. ©2018 Håkan Pettersson et al., published by De Gruyter, Berlin/Boston.

  • 17.
    Aghaeipour, Mahtab
    et al.
    Lund University, Lund, Sweden.
    Pistol, Mats-Erik
    Lund University, Lund, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). Lund University, Lund, Sweden.
    Comparative study of absorption efficiency of inclined and vertical InP nanowires2017In: Physics, Simulation, and Photonic Engineering of Photovoltaic Devices VI / [ed] A. Freundlich, L. Lombez, M. Sugiyama, Bellingham, WA: SPIE - International Society for Optical Engineering, 2017, Vol. 10099, article id UNSP 100990SConference paper (Refereed)
    Abstract [en]

    Geometrically designed III-V nanowire arrays are promising candidates for optoelectronics due to their possibility to excite nanophotonic resonances in absorption spectra. Strong absorption resonances can be obtained by proper tailoring of nanowire diameter, length and pitch. Such enhancement of the light absorption is, however, accompanied by undesired resonance dips at specific wavelengths. In this work, we theoretically show that tilting of the nanowires mitigates the absorption dips by exciting strong Mie resonances. In particular, we derive a theoretical optimum inclination angle of about 30 degrees at which the inclined nanowires gain 8% in absorption efficiency compared to vertically standing nanowires in a spectral region matching the intensity distribution of the sun. The enhancement is due to engineering the excited modes inside the nanowires regarding the symmetry properties of the nanowire/light system without increasing the absorbing material. We expect our results to be important for nanowire-based photovoltaic applications. © 2017 SPIE.

  • 18.
    Aghaeipour, Mahtab
    et al.
    Solid State Physics and NanoLund, Lund University, Lund, Sweden.
    Pistol, Mats-Erik
    Solid State Physics and NanoLund, Lund University, Lund, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). Solid State Physics and NanoLund, Lund University, Lund, Sweden.
    Considering Symmetry Properties of InP Nanowire/Light Incidence Systems to Gain Broadband Absorption2017In: IEEE Photonics Journal, ISSN 1097-5764, E-ISSN 1943-0655, Vol. 9, no 3, article id 4501310Article in journal (Refereed)
    Abstract [en]

    Geometrically designed III-V nanowire arrays are promising candidates for disruptive optoelectronics due to the possibility of obtaining a strongly enhanced absorption resulting from nanophotonic resonance effects. With normally incident light on such vertical nanowire arrays, the absorption spectra exhibit peaks that originate from excitation of HE1m waveguide modes in the constituent nanowires. However, the absorption spectra typically show dips between the absorption peaks. Conventionally, such weak absorption has been counteracted by either making the nanowires longer or by decreasing the pitch of the array, both alternatives effectively increasing the volume of absorbing material in the array. Here, we first study two approaches for compensating the absorption dips by exciting additional Mie resonances: 1) oblique light incidence on vertical InP nanowire arrays and 2) normal light incidence on inclined InP nanowire arrays. We then show that branched nanowires offer a novel route to achieve broadband absorption by taking advantage of simultaneous excitations of Mie resonances in the branches and guided HE1m modes in the stem. Finite element method calculations show that the absorption efficiency is enhanced from 0.72 for vertical nanowires to 0.78 for branched nanowires under normal light incidence. Our work provides new insight for the development of novel efficient photovoltaics with high efficiency and reduced active material volume.

  • 19.
    Ahlqvist Nilsson, Petra
    et al.
    Halmstad University, School of Information Technology.
    Svensson Tynkkynen, Carolin
    Halmstad University, School of Information Technology.
    Förslag på design av digitala knuffar för vägledning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Decisions are increasingly made in connection with screens, amongst other things due to thecontinuous growth of e-commerce. When people make decisions they are influenced by thechoice environment as well as heuristics and biases, which are mental shortcuts. People areinfluenced by heuristics and biases as it is often difficult for them to make decisions based onall of the information presented. Nudges are a way to guide people to make specific choiceswithout limiting their freedom and have primarily been used in non-digital contexts, but havenow also been introduced in informatics. However, in order for nudges to be able to bedeveloped and used digitally it is important to have knowledge about how people make choicesand the effect nudges have. Previous research on digital nudges also asks for studies on howdigital nudges can be designed and their impact on people's choices online.As nudging is a relatively new term in informatics, as well as research regarding the topic isinquired, this study investigate how digital nudges can be designed to guide people tosustainable choices online. The study was conducted with a design research approach wheredigital nudges were designed based on four different heuristics and biases. The nudges wereapplied on an e-commerce website and tested by means of a prototype. The process fordesigning and evaluating the digital nudges was iterated four or five times to in an exploratoryway test different ways to design the nudges in relation to the research question. The studycontribute with a number of suggestions on how digital nudges can be designed based onheuristics and biases, with guidance and sustainability as focal points.

  • 20.
    Ahlström, Tove
    et al.
    Halmstad University, School of Information Technology.
    Kaikkonen, Amanda
    Halmstad University, School of Information Technology.
    Hur kan ett e-hälsostöd designas för att främja inre motivation till fysisk rehabilitering?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Due to an increased need for health care, physical rehabilitation is an area where there is a growing need for implementation of e-health support. An unsuccessful rehabilitation plan could potentially lead to a patient's pain or discomfort not being improved as planned. This may lead to the patient needing more rehabilitation care than what had been required if the rehabilitation plan had been completed from the beginning. In addition to this being a cost for the patients themselves, it also entails an extra cost for health care services. Motivation is considered one of the main aspects to take into account as it influences people's ability and willingness to do something. If the motivational aspect is ignored in the design of e- health support in a rehabilitation context, there is a risk that the design will not possess the functions that can be crucial for the user to use the digital support. Although rehabilitation patients are provided with proper physiotherapy exercises they do not perform their exercises, which may be due to their lack of intrinsic motivation. Despite this dilemma, there are few studies that investigate how digital support can be designed to promote intrinsic motivation in a rehabilitation context. The study therefore aimed to examine how an e-health support can be designed to promote intrinsic motivation in a rehabilitation context. The research question was examined using a design-oriented approach. In order to investigate intrinsic motivation, the concept is concretized to the three psychological needs: autonomy, competence and relatedness. The study then resulted in nine design proposals that informed how an e-health support could be designed to promote intrinsic motivation by supporting the three basic psychological needs: autonomy, competence and relatedness.

  • 21.
    Ahmadi, Lina
    Halmstad University, School of Information Technology.
    Green Driving Application: Eco Driving2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Eco-driving has acquired great importance in recent years because it is a way to reduce energy consumption that can be applied to any type of vehicle. However, for these rules to be applied requires a process of continuous learning and motivation. For this reason many eco-driving assistants have emerged.

    This paper presents Green Driving, a driver safety app for Android that detects inattentive driving behaviors and gives corresponding feedback to drivers, scoring their driving and alerting them in case their behaviors are unsafe.  It’s about changing a person’s driving behavior by providing some kind of advice to the driver.  I have worked on an algorithm that is meant to reduce the fuel consumption of users. The algorithm is deployed in an android application.

    This application “Green Driving” is aimed at users with cars. It is basically like an assistant, suggesting the user when he should make the right gear changes, when to increase/decrease speed and avoids hard braking and rapid acceleration and etc. It is in order to drive economically, ecologic and in turn save money and safety. This is a smart way of letting a user drive economically and ecologic since almost everyone has an Android smartphone now. 

  • 22.
    Aichernig, Bernhard K.
    et al.
    Graz University of Technology, Graz, Austria.
    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). Department of Informatics, University of Leicester, Leicester, UK.
    Tappler, Martin
    Graz University of Technology, Graz, Austria.
    Taromirad, Masoumeh
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Model Learning and Model-Based Testing2018In: Machine Learning for Dynamic Software Analysis: Potentials and Limits / [ed] Amel Bennaceur, Reiner Hähnle, Karl Meinke, Heidelberg: Springer, 2018, p. 74-100Conference paper (Refereed)
    Abstract [en]

    We present a survey of the recent research efforts in integrating model learning with model-based testing. We distinguished two strands of work in this domain, namely test-based learning (also called test-based modeling) and learning-based testing. We classify the results in terms of their underlying models, their test purpose and techniques, and their target domains. © Springer International Publishing AG

  • 23.
    Aires, Nibia
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    A guide to the Fortran programs to calculate inclusion probabilities for conditional Poisson sampling and Pareto pi ps sampling designs2004In: Computational statistics (Zeitschrift), ISSN 0943-4062, E-ISSN 1613-9658, Vol. 19, no 3, p. 337-345Article in journal (Refereed)
    Abstract [en]

    Conditional Poisson Sampling and Pareto pips Sampling designs are sampling methods with fixed sample size and with inclusion probabilities proportional to given size measures.. Algorithms were introduced to calculate first and second exact inclusion probabilities for both schemes. Methods were also provided to adjust the parameters to get predetermined inclusion probabilities. In this paper, the Fortran procedures are introduced and documented. Moreover, guidelines are provided for their use as well as examples and the programs codes commented.

  • 24.
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    The Influence Of Generativity On Value Creation – A Study Of Digitized Products2015In: 8th IADIS International Conference on Information Systems / [ed] Miguel Baptista Nunes, Pedro Isaias, Philip Powell, IADIS Press, 2015, p. 51-60Conference paper (Refereed)
    Abstract [en]

    The advancement of digital technologies is driving traditional product oriented businesses to move from selling product to selling solutions. In order to exploit business potentials from technology, it is important to understand the potential of the technology and how it influences the value creation in a digital environment where it is developed and to be deployed. To understand this changing environment, I have studied remote diagnostics as an example of digital technology within the vehicle industry as a source of new value for business. The findings show that digitized products not only helps to solve existing problems in providing services but also provides potential to generate value for new products and services in the networked environment. An implication from the findings for product oriented firms is that value creation with digitized products requires new business processes. Based on the findings, a discussion is presented about how generativity influences value creation via value in design, governance and networking in a digital ecosystem.

  • 25.
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Towards Servitization in the Age of Digital Innovation: A Case from Vehicle Industry2012Conference paper (Refereed)
    Abstract [en]

    The advancement in digital technologies drives industries to change their core businesses which present number of challenges. One of them is transformation of manufacturing industries towards servitization. This paper reports empirical findings from an on-going project related to servitization in the age of digital innovation. The research study is in the context of the vehicle industry and concerns e-maintenance services based on remote diagnostics technologies. It explores the servitization of vehicle industry in the age of digital innovation. Such innovations embark challenges to innovation environment. A study in this regard has been conducted and it revealed the challenges related to the design, organizational strategy and organizational transformation.

  • 26.
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Value Creation in Digital Ecosystem – A Study of Remote Diagnostics2013Conference paper (Refereed)
    Abstract [en]

    The advancement of digital technologies is driving traditional product oriented businesses to move from selling product to selling solutions. In order to exploit business potentials from technology, it is necessary to understand the technological capacity and how it influences the value creation in the environment where it is deployed. I study remote diagnostics as an example of digital technology within the vehicle industry. I found that this technology provides potential to generate new value. To create this value, traditional product oriented organizations are required to create value in different way than traditional mode of creating value. In this paper, I show that how generative capacity of remote diagnostics technology creates value in digital ecosystem.

  • 27.
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab). University of Gothenburg, Gothenburg, Sweden.
    Value Network Transformation: Digital Service Innovation in the Vehicle Industry2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Advancement in digital technology is rapidly changing the contemporary landscape of business and associated networks for manufacturing firms. Many traditional physical products are now being embedded with digital components, providing them digital capability to become digitized products. The digitization of physical products has become an important driver for digital service innovation within manufacturing industries. Such digital service innovation transforms value networks of manufacturing firms in various industries. While digitization of products and digital service innovation can be observed in many manufacturing industries, this thesis focuses on the transformation of value networks within the vehicle industry.

    This thesis is a collection of papers and a cover paper. The thesis reports from a collaborative project in the vehicle industry. The project explored new digital services for vehicles based on remote diagnostics technology. The exploration and conceptualization of digital services is investigated in a collaborative manner with participants from the vehicle industry. The results reflect that there is a paradigm shift for manufacturing firms digitizing their products, and stretching the business scope from product to solution oriented business.

    This thesis contributes to the existing literature on digital innovation with insights on the transformation of value networks in the vehicle industry. The research question addressed in this thesis is: How are value networks of manufacturing firms transformed by digital service innovation? To answer the question, this thesis conceptualizes how the value creating pattern of digitized products transforms value networks of manufacturing firms. A model is presented that reflects how the symbiotic value relationship between the digitized product and digital services transforms the roles, relationships and exchanges in the value networks of manufacturing firms. The model can serve as an analytical tool to further advance the knowledge on business aspects in digital innovation. This thesis contributes to practice by providing an understanding of how manufacturing firms can leverage value of digitized products and digital services in value networks.

  • 28.
    Akram, Asif
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Bergquist, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). University of Gothenburg.
    Åkesson, Maria
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Digital Visions vs. Product Practices: Understanding Tensions in Incumbent Manufacturing Firms2014In: Proceedings of the Annual Hawaii International Conference on System Sciences / [ed] Ralph H. Sprague, Jr., Los Alamitos, CA: IEEE Computer Society, 2014, p. 4516-4525Conference paper (Refereed)
    Abstract [en]

    Incumbent manufacturing firms face challenges when expanding their product focus with digital services. Such expansion creates tensions in organizations in the servitization process. While management visions and conceptualizes new service oriented businesses, the actual practice of implementing these service concepts is influenced by the product paradigmatic way of thinking in the organization. This dominant thinking creates tensions between business visions and business practice. We use the case of remote diagnostics services to provide insights into a manufacturing firm’s attempt to transform the dominant oriented business models into a new networked environment. We suggest that such acts that may or may not lead to transition are lingered by dominant logics related to the product focus. This indicates that firms are required to embed new logics into their existing practice in order to exploit the full potential of digital technology. © 2014 IEEE.

  • 29.
    Akram, Asif
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Åkesson, Maria
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    A Research Framework to Study how Digital Service Innovation Transforms Value Networks2011In: Proceedings of IRIS 2011 / [ed] Leino, Timo, Turku, Finland: Turku Center for Computer Science , 2011, p. 29-40Conference paper (Refereed)
    Abstract [en]

    This paper reports from preparations in an ongoing research study concerning how digital service innovation transforms value networks in manufacturing industries. The research study is in the context of the vehicle industry and concerns digital e-maintenance services based on remote diagnostics systems. This digital service innovation in particular is of great importance since manufacturing industries have great potential to expand their business and found new and extended boundaries and relationships with other stakeholder in a network they are attached to. Core challenges and opportunities for digital service innovation will lead us to the study of its influence on the business and innovation environment i.e. the value network. This paper presents a framework to study how digital service innovation transforms value networks based on literature reviews on value network, digital innovation and transformation of value networks.

  • 30.
    Akram, Asif
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Åkesson, Maria
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Value Network Transformation By Digital Service Innovation In The Vehicle Industry2011In: Proceedings of the 15th Pacific Asia Conference on Information Systems | Pacific Asia Conference on Information Systems (PACIS), Brisbane, Australia: Association for Information Systems, 2011Conference paper (Other academic)
    Abstract [en]

    This paper reports from preparations in an ongoing research study concerning how digital service innovation transforms value networks in the vehicle industry. The research study concerns digital services based on remote diagnostics systems. This digital service innovation in particular is of great importance since the vehicle industry has great potential to expand its business and found new and extended boundaries and relationships with other stakeholder in the networks they are attached to. Core challenges and opportunities for digital service innovation will lead us to the study of its influence on the business and innovation environment i.e. the value network. In this paper, we propose three propositions to study transformation from product oriented value networks to digital service oriented value networks.

  • 31.
    Akram, Asif
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Åkesson, Maria
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Bergquist, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Balancing Generativity and Control of Digitized Products – A Study of Digitized Buses and Remote Diagnostic ServicesManuscript (preprint) (Other academic)
  • 32.
    AL, Cihan
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Koroglu, Kubra
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Detection of the Change Point and Optimal Stopping Time by Using Control Charts on Energy Derivatives2011Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
  • 33.
    Alam, Ashraful
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Ul-Abdin, Zain
    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).
    Parallelization of the Estimation Algorithm of the 3D Structure Tensor2012In: 2012 International Conference on Reconfigurable Computing and FPGAs, ReConFig 2012 / [ed] Peter Athanas, René Cumplido & Eduardo de la Torre, Piscataway, N.J.: IEEE Press, 2012, article id 6416771Conference paper (Refereed)
    Abstract [en]

    The three dimensional structure tensor algorithm (3D-STA) is often used in image processing applications to compute the optical flow or to detect local 3D structures and their directions. This algorithm is computationally expensive due to many computations that are required to calculate the gradient, the tensor, and to smooth every pixel of the image frames. Therefore, it is important to parallelize the implementation to achieve high performance. In this paper we present two parallel implementations of 3D-STA; namely moderately parallelized and highly parallelized implementation, on a massively parallel reconfigurable array. Finally, we evaluate the performance of the generated code and results are compared with another optical flow implementation. The throughput achieved by the moderately parallelized implementation is approximately half of the throughput of the Optical flow implementation, whereas the highly parallelized implementation results in a 2x gain in throughput as compared to the optical flow implementation. © 2012 IEEE.

  • 34.
    Alasjö, Alexander
    Halmstad University, School of Information Technology.
    Sidokanalattack mot knappsats för elektroniskt passersystem2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through an exploratory experiment using electromagnetic side-channel attack against a keypad for a commercial entry system it is demonstrated that information leakage through side-channels are an ongoing issue and may make entry systems vulnerable by recording of user data.

    Using simple radio equipment, keypresses can be recorded and decoded by undesired electromagnetic radiation and theoretically it is possible to carry out the attack on a longer distance with a specially designed antenna and a custom recieiver.

    The report discusses emission security in consumer products which in military context is termed Tempest or compromising emanations (Swedish: RÖS) and requires expensive tests to be detected and handled.

    The EMC regulations (electromagnetic compatibility) handles radiation and influence of electromagnetic waves in electronic apparatus and nets, but not directly how information can leak from information technology equipment which this report wants to problematize.

  • 35.
    Albayrak, Aras
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Automatic Pose and Position Estimation by Using Spiral Codes2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is about providing the implementation of synthesis, detection of spiral symbols and estimating the pan/tilt angle and position by using camera calibration. The focus is however on the latter, the estimation of parameters of localization.

    Spiral symbols are used to be able to give an object an identity as well as to locate it. Due to the spiral symbol´s characteristic shape, we can use the generalized structure tensor (GST) algorithm which is particularly efficient to detect different members of the spiral family. Once we detect spirals, we know the position and identity parameters of the spirals within an apriori known geometric configuration (on a sheet of paper). In turn, this information can be used to estimate the 3D-position and orientation of the object on which spirals are attached using a camera calibration method.

     

    This thesis provides an insight into how automatic detection of spirals attached on a sheet of paper, and from this, automatic deduction of position and pose parameters of the sheet, can be achieved by using a network camera. GST algorithm has an advantage of running the processes of detection of spirals efficiently w.r.t detection performance and computational resources because it uses a spiral image model well adapted to spiral spatial frequency characteristic. We report results on how detection is affected by zoom parameters of the network camera, as well as by the GST parameters; such as filter size. After all spirals centers are located and identified w.r.t. their twist/bending parameter, a flexible technique for camera calibration, proposed by Zhengyou Zhang implemented in Matlab within the present study, is performed. The performance of the position and pose estimation in 3D is reported.

    The main conclusion is, we have reasonable surface angle estimations for images which were taken by a WLAN network camera in different conditions such as different illumination and different distances. 

  • 36.
    Aldebes, Mujtaba
    Halmstad University, School of Information Technology.
    Smart Shopping Cart: Automatisering av handelsprocessen vid fysiska butiker, teknisk innovation2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thefts and shoplifting is a big problem for local stores, additionally the development of e-commerce is a deciding factor for the success of physical stores and their profitability. An increasing amount of money is being invested in security solutions, guards and other related personnel. 

    The goal of this Bachelors thesis has been to develop a product for a modern and innovative smart shopping cart. The resulting cart is a tool that is more suitable for the benefit of consumers and their need for a more comfortable shopping experience, it has the benefit of streamlining the shopping process which in turn could attract repeat customers. 

    Through the use of new technology as well as the Internet and new functions at a competitive price point there is a great opportunity to market this product. The shopping cart uses image analysis and a load cell which alleviates the need for customers to manually scan each article for purchase, instead it is identified and registered as it is placed in the shopping cart. 

    The prototype has been compared to other solutions and conclusions have been drawn as to the optimality of the product fulfill the purpose.

  • 37.
    Aldén, Victoria
    et al.
    Halmstad University, School of Information Technology.
    Gunnarsson, Ebba
    Halmstad University, School of Information Technology.
    Användningen av Robotic Process Automation i kommunala förvaltningars beslutsstödsprocesser: En studie om vilka konsekvenser som kan uppstå genom användningen av RPA och påverkan på kommunala beslutsstödsprocesser för försörjningsstöd2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In communal organizations there has previously not existed a law that allowed automated decision support, it was during the year 2018 that the law changed. Previous research has focused on automation in the private business sector, which has created a lack of research on public organizations. Following the change in the law, Social services have started to automate the decision support in their decision support processes. The automation takes place using the software technology RPA (Robot Process Automation). RPA can only handle processes that are regulated and structured. It forces the Social services to define and structure their decision support processes that were previously manually performed by administrators. It involves creation of consequences that affects the decision support process and leads to the study ́s question: How is the decision support process in communal organizations affected using RPA? A qualitative method has been used in the collection of literature and empirical data, in order to be able to identify the consequences and its impact in the decision support process. The identified consequences presented in the study's conclusion are divided into the categories: consequences based on RPA and consequences based on the administrators. The consequences identified in the study have differed between the communal organizations, depending on how they interpreted the law and whether RPA has started to be used in the communes yet.

  • 38.
    Alendal, Gunnar
    et al.
    NTNU, Gjøvik, Norway.
    Dyrkolbotn, Geir Olav
    NTNU, Gjøvik, Norway & Norwegian Defence Cyber Academy (NDCA), Jørstadmoen, Norway.
    Axelsson, Stefan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Forensics acquisition – Analysis and circumvention of samsung secure boot enforced common criteria mode2018In: Digital Investigation. The International Journal of Digital Forensics and Incident Response, ISSN 1742-2876, E-ISSN 1873-202X, Vol. 24, no Suppl., p. S60-S67Article in journal (Refereed)
    Abstract [en]

    The acquisition of data from mobile phones have been a mainstay of criminal digital forensics for a number of years now. However, this forensic acquisition is getting more and more difficult with the increasing security level and complexity of mobile phones (and other embedded devices). In addition, it is often difficult or impossible to get access to design specifications, documentation and source code. As a result, the forensic acquisition methods are also increasing in complexity, requiring an ever deeper understanding of the underlying technology and its security mechanisms. Forensic acquisition techniques are turning to more offensive solutions to bypass security mechanisms, through security vulnerabilities. Common Criteria mode is a security feature that increases the security level of Samsung devices, and thus make forensic acquisition more difficult for law enforcement. With no access to design documents or source code, we have reverse engineered how the Common Criteria mode is actually implemented and protected by Samsung's secure bootloader. We present how this security mode is enforced, security vulnerabilities therein, and how the discovered security vulnerabilities can be used to circumvent Common Criteria mode for further forensic acquisition. © 2018 The Author(s). Published by Elsevier Ltd on behalf of DFRWS.

  • 39.
    Alhamarna, Ahmed
    et al.
    Halmstad University, School of Information Technology.
    Kjellgren, Simon
    Halmstad University, School of Information Technology.
    IDENTIFIERING AV ELEKTRONIKSKROT2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is the result of a survey carried out by two students at Halmstad University. The study was conducted at the request of the recycling company, with the purpose to explore opportunities for streamlining the screening pro- cess of electronic waste products. The question that was asked was if RFID could be used for identification of the scrap. The project members started their work to investigate if RFID was the best identification method where the advantages and disadvantages of various automated systems were com- pared. The conclusion drawn was that RFID could be a viable solution in the future, provided that manufacturers of electronics integrate RFID tags into their products. Given that increasingly more producers are using RFID to locate and identify their products during production and the falling price of passive tags, it is possible that labeling products with RFID tags could become a standard, both for more efficient logistics and a more efficient re- cycling process. 

  • 40.
    Alharthi, Mohannad
    et al.
    School of Computing, Queen's University, Kingston, Ontario, Canada.
    Taha, Abd-Elhamid M.
    Electrical Engineering Department, Alfaisal University, Riyadh, Saudi Arabia.
    Vasilev, Viktor
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Atkinson, Kevin
    Department of Computer Science, Rice University, Houston, USA.
    An Acumen/NS-3 integration for modeling networked Cyber-Physical Systems2014Conference paper (Refereed)
    Abstract [en]

    Capturing physical phenomena such as node mobility or wave propagation is challenging in current network simulators, and is mostly achieved through crude abstractions. Despite being operationally efficient, such abstractions adversely affect simulation credibility. To realize more accurate modeling, we are currently developing a simulation environment integrating a hybrid modeling language into a mainstream network simulator. This paper gives a preliminary overview of our efforts. For illustration, an example simulation scenario with some basic mobility is described. © 2014 IEEE.

  • 41.
    Ali Hamad, Rebeen
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Järpe, Eric
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Lundström, Jens
    JeCom Consulting, Halmstad, Sweden.
    Stability analysis of the t-SNE algorithm for human activity pattern data2018Conference paper (Refereed)
    Abstract [en]

    Health technological systems learning from and reacting on how humans behave in sensor equipped environments are today being commercialized. These systems rely on the assumptions that training data and testing data share the same feature space, and residing from the same underlying distribution - which is commonly unrealistic in real-world applications. Instead, the use of transfer learning could be considered. In order to transfer knowledge between a source and a target domain these should be mapped to a common latent feature space. In this work, the dimensionality reduction algorithm t-SNE is used to map data to a similar feature space and is further investigated through a proposed novel analysis of output stability. The proposed analysis, Normalized Linear Procrustes Analysis (NLPA) extends the existing Procrustes and Local Procrustes algorithms for aligning manifolds. The methods are tested on data reflecting human behaviour patterns from data collected in a smart home environment. Results show high partial output stability for the t-SNE algorithm for the tested input data for which NLPA is able to detect clusters which are individually aligned and compared. The results highlight the importance of understanding output stability before incorporating dimensionality reduction algorithms into further computation, e.g. for transfer learning.

  • 42.
    Aljarbouh, Ayman
    et al.
    Centre de Recherche INRIA, Rennes, France.
    Zeng, Yingfu
    Rice University, Houston, Texas, United States.
    Duracz, Adam
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Caillaud, Benoît
    Centre de Recherche INRIA, Rennes, France.
    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, United States.
    Chattering-Free Simulation for Hybrid Dynamical Systems: Semantics and Prototype Implementation2016In: 2016 IEEE Intl Conference on Computational Science and Engineering (CSE) and IEEE Intl Conference on Embedded and Ubiquitous Computing (EUC) and 15th Intl Symposium on Distributed Computing and Applications for Business Engineering (DCABES) / [ed] Randall Bilof, Los Alamitos: IEEE Computer Society, 2016, p. 412-422, article id 7982279Conference paper (Refereed)
    Abstract [en]

    Chattering is a fundamental phenomenon that is unique to hybrid systems, due to the complex interaction between discrete dynamics (in the form of discrete transitions) and continuous dynamics (in the form of time). In practice, simulating chattering hybrid systems is challenging in that simulation effectively halts near the chattering time point, as an infinite number of discrete transitions would need to be simulated. In this paper, formal conditions are provided for when the simulated models of hybrid systems display chattering behavior, and methods are proposed for avoiding chattering “on the fly” in runtime. We utilize dynamical behavior analysis to derive conditions for detecting chattering without enumeration of modes. We also present a new iterative algorithm to allow for solutions to be carried past the chattering point, and we show by a prototypical implementation how to generate the equivalent chattering-free dynamics internally by the simulator in the main simulation loop. The concepts are illustrated with examples throughout the paper. © 2016 IEEE.

  • 43.
    Allgayer, Rodrigo
    et al.
    Electrical Engineering Department, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
    Muller, Ivan
    Electrical Engineering Department, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
    Pereira, Carlos
    Electrical Engineering Department, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
    Cavalcante, Andre
    Electronic and Telcomunication Department, Federal University of Amazonas (UFAM), Manaus, Brazil.
    Pignaton de Freitas, Edison
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Institute of Informatics, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Analysis of distributed control system using remote method invocation in wireless network2011In: IECON 2011 Proceedings: 37th Annual Conference of the IEEE Industrial Electronics Society, New York: IEEE, 2011, p. 346-351, article id 6119277Conference paper (Refereed)
    Abstract [en]

    This work presents the temporal analysis for a distributed differential control system for a mobile robot deployed on a wireless network using the SunSPOT platform. The system is programmed in Java and each of its part is executed in a distinct processor which cooperates via a wireless network. The communication between the network nodes is made by remote procedure calls, which are implemented by a minimum version of the Java RMI (mRMI), presented in this work. Simulation results are compared to experimental data acquired by the deployment of the system on real devices, the SunSPOTs. The comparisons reveal that the distributed solution presents fairly good results besides the inserted errors due to the wireless communication. © 2011 IEEE.

  • 44.
    Alm, Ilkoo
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Johansson, Ingegerd
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Cognitive aspects in visualisation of complex data2001In: CISST'2001: proceedings of the International Conference on Imaging Science, Systems, and Technology : Las Vegas, Nevada, USA, June 25-28, 2001 / [ed] Arabnia, H.R., Avalon, Athens, USA: CSREA Press, 2001, p. 633-638Conference paper (Refereed)
    Abstract [en]

    Information Visualization applications are dealing with fundamental difficulties related to overlap in cognitive models between designers and users, goal ambiguity, and accuracy in search strategies These difficulties are more obvious in applications aimed at reducing information overload by general users, than in applications aimed at visualising scientific data. General users have very likely quite different cognitive reference for approaching an abstract complex task, than designers. This can result in designs which can unintentionally increase information overload by users. In visualisation of scientific data the overlap of cognitive reference between specialists and designs is very likely much higher, but we need methods which can facilitate data exploration in real-time interaction. One possibility to facilitate exploration in a more or less systematic way is by means of metaphors which can support human perception in searching for patterns.

  • 45.
    Almgren, David
    et al.
    Halmstad University, School of Information Technology.
    Alshammari, Hussam
    Halmstad University, School of Information Technology.
    SmartBand Alert: Ett armband för säkerhet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Safety is a topic that is frequently discussed and spoken of in today’s society. An enhanced security for each individual is something many strive for in various industries. One of these is how to make the public feel more secure when the person in question, for example, is out walking late at night. The goal of this bachelors thesis is thus to describe and explain the product that has been developed to get ordinary people to feel more secure wherever they are. The chosen solution for this issue was hence to develop the product SmartBand Alert which consists of two parts. A bracelet and an application for IOS and Android. This bracelet should, by certain connectivity cooperate with the user’s phone to notify family members and/or others when the person thinks or knows that he or she is in danger. These persons will be notified with information about the person who has activated the alarm to simply and easily take the necessary actions to help the person. The product is designed to be used by anyone regardless of gender, age, and other characteristics individuals may hold.

  • 46.
    Almgren Mason, Suzanne
    et al.
    Halmstad University, School of Social and Health Sciences (HOS), Center for Social Analysis (CESAM), Social Change, Learning and Social Relations (SLSR).
    Hansson, Agneta
    Halmstad University, School of Business and Engineering (SET), Centre for Innovation, Entrepreneurship and Learning Research (CIEL).
    Svensson, Bertil
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Börjesson, Emma
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Bridging Scientific Cultures in a Regional Health Care Context2010In: VIII Triple Helix International Conference on University, Industry and Government Linkages: BOOK OF ABSTRACTS, 2010Conference paper (Other academic)
    Abstract [en]

    Embedded Intelligent Systems (EIS) is the joint research field of the four collaborating laboratories at the School of Information Science, Computer and Electrical Engineering (IDE) at Halmstad University. The research of the four labs is integrated into a strong concerted research environment within embedded systems (EIS) - with a perspective reaching from the enabling technology via new system solutions and intelligent applications to end user aspects and business models. It is an expanding research area with many applications, not least ones that exist in everyday life.EIS is an important research environment contributing to the regional Triple Helix innovation system Healthcare Technology which the region has pointed out as a prioritised development sector. With its strong connections to both established and new, expanding firms hived off from the university, the research environment is active in the Healthcare Technology Alliance, a network of around sixty companies, counties and health care providers in south-western Sweden with the aim of developing the region into a leading arena for the development of health technology products and services. Several projects together with these participants concern both research and technology transfer.An integrated gender and gender equality perspective in innovations within the health technology area is necessary in order to be able to meet the needs of an ageing population with quality innovations. The relevancy of a gender perspective is clear in relation to the fact that about 70% of all those older than 75 years are women. Older women are on average cared for in hospital twice as long as men, partly due to differing disease panoramas, but also because men are more often cared for in the home by a woman while the women who live longer more often live alone. With the expansion of home-help and home nursing new needs follow and it is likely that a gender perspective will become necessary for the development of products and services that can make daily life easier for the elderly. The gender perspective also has relevance from the point of view of care staff. New technology is developed for application within the health and care sector where the larger professional groups consist mainly of women. The technology, most often designed by men, is used by women. With this in mind it is clear that an important aspect of good innovations is that the end users are involved in the innovation process.Based on an awareness of the need for a more articulated gender perspective within the research environment, in order to meet the needs expressed above, an application for a gender inclusive R&D project was handed in to the VINNOVA programme Applied Gender Research in Strong Research and Innovation Environments. The G-EIS project (Gender Perspective on Embedded Intelligent Systems - Application in Healthcare Technology) was approved and started in 2009. The project involves researchers from the EIS research environment as well as representatives from companies and the public sector.The project participants are on the whole agreed on the need for a gender perspective in the R&I environment, but struggle with the meeting of two epistemologically opposed theories of science. The understanding within gender studies that research and production both create reality and are informed by it is not always accepted within the areas of natural science. Engineering and other technological sciences not only consider aspects of science to be separate from reality, but also seek positivistic proof in research, something not always possible in the more qualitative research of the social sciences. Researching how these two perspectives meet within this specific project is the topic of this paper.

  • 47.
    Alonso-Fernandez, Fernando
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Bigun, Josef
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    A survey on periocular biometrics research2016In: Pattern Recognition Letters, ISSN 0167-8655, E-ISSN 1872-7344, Vol. 82, part 2, p. 92-105Article in journal (Refereed)
    Abstract [en]

    Periocular refers to the facial region in the vicinity of the eye, including eyelids, lashes and eyebrows. While face and irises have been extensively studied, the periocular region has emerged as a promising trait for unconstrained biometrics, following demands for increased robustness of face or iris systems. With a surprisingly high discrimination ability, this region can be easily obtained with existing setups for face and iris, and the requirement of user cooperation can be relaxed, thus facilitating the interaction with biometric systems. It is also available over a wide range of distances even when the iris texture cannot be reliably obtained (low resolution) or under partial face occlusion (close distances). Here, we review the state of the art in periocular biometrics research. A number of aspects are described, including: (i) existing databases, (ii) algorithms for periocular detection and/or segmentation, (iii) features employed for recognition, (iv) identification of the most discriminative regions of the periocular area, (v) comparison with iris and face modalities, (vi) soft-biometrics (gender/ethnicity classification), and (vii) impact of gender transformation and plastic surgery on the recognition accuracy. This work is expected to provide an insight of the most relevant issues in periocular biometrics, giving a comprehensive coverage of the existing literature and current state of the art. © 2015 Elsevier B.V. All rights reserved.

  • 48.
    Alonso-Fernandez, Fernando
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Bigun, Josef
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    An Overview of Periocular Biometrics2017In: Iris and Periocular Biometric Recognition / [ed] Christian Rathgeb & Christoph Busch, London: The Institution of Engineering and Technology , 2017, p. 29-53Chapter in book (Refereed)
    Abstract [en]

    Periocular biometrics specifically refers to the externally visible skin region of the face that surrounds the eye socket. Its utility is specially pronounced when the iris or the face cannot be properly acquired, being the ocular modality requiring the least constrained acquisition process. It appears over a wide range of distances, even under partial face occlusion (close distance) or low resolution iris (long distance), making it very suitable for unconstrained or uncooperative scenarios. It also avoids the need of iris segmentation, an issue in difficult images. In such situation, identifying a suspect where only the periocular region is visible is one of the toughest real-world challenges in biometrics. The richness of the periocular region in terms of identity is so high that the whole face can even be reconstructed only from images of the periocular region. The technological shift to mobile devices has also resulted in many identity-sensitive applications becoming prevalent on these devices.

  • 49.
    Alonso-Fernandez, Fernando
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Bigun, Josef
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Best Regions for Periocular Recognition with NIR and Visible Images2014In: 2014 IEEE International Conference on Image Processing (ICIP), Piscataway, NJ: IEEE Press, 2014, p. 4987-4991Conference paper (Refereed)
    Abstract [en]

    We evaluate the most useful regions for periocular recognition. For this purpose, we employ our periocular algorithm based on retinotopic sampling grids and Gabor analysis of the spectrum. We use both NIR and visible iris images. The best regions are selected via Sequential Forward Floating Selection (SFFS). The iris neighborhood (including sclera and eyelashes) is found as the best region with NIR data, while the surrounding skin texture (which is over-illuminated in NIR images) is the most discriminative region in visible range. To the best of our knowledge, only one work in the literature has evaluated the influence of different regions in the performance of periocular recognition algorithms. Our results are in the same line, despite the use of completely different matchers. We also evaluate an iris texture matcher, providing fusion results with our periocular system as well. © 2014 IEEE.

  • 50.
    Alonso-Fernandez, Fernando
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Bigun, Josef
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Biometric Recognition Using Periocular Images2013Conference paper (Other academic)
    Abstract [en]

    We present a new system for biometric recognition using periocular images based on retinotopic sampling grids and Gabor analysis of the local power spectrum at different frequencies and orientations. A number of aspects are studied, including: 1) grid adaptation to dimensions of the target eye vs. grids of constant size, 2) comparison between circular- and rectangular-shaped grids, 3) use of Gabor magnitude vs. phase vectors for recognition, and 4) rotation compensation between query and test images. Results show that our system achieves competitive verification rates compared with other periocular recognition approaches. We also show that top verification rates can be obtained without rotation compensation, thus allowing to remove this step for computational efficiency. Also, the performance is not affected substantially if we use a grid of fixed dimensions, or it is even better in certain situations, avoiding the need of accurate detection of the iris region.

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