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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.
    Abdulrazzak, Shahm
    et al.
    Halmstad University, School of Information Technology.
    Mattsson, Tor
    Halmstad University, School of Information Technology.
    Java Auto Grader2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The process of grading code submissions in programming courses is time-consuming and error-prone. To address this issue, we propose a project that automates the testing and grading process for Java code submissions at Halmstad University. Our approach leverages property-based testing using the JUnit Quick-Check library to generate tests and test reports automatically.

     

    The tool we demonstrate in this project is designed to provide students with immediate feedback on their code submissions and reduce the workload for instructors. By automatically generating tests and test reports, our approach ensures that code submissions meet the required specifications and are free from common errors. The com.pholser library is utilized to implement the property-based testing approach.

     

    We believe that our project has the potential to improve the grading process for programming courses and provide a more efficient and effective way of assessing student code submissions. Our implementation can be easily extended to support other programming languages and can be integrated with existing learning management systems to provide a seamless experience for instructors and students alike.

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  • 3.
    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.

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  • 4.
    Abika, Collins
    Halmstad University, School of Information Technology.
    Complaint system for Health Care Center Hjärtat2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today the IT support could be overwhelmed with loads of requests from the clients within the Health care center Hjärtat (Also known as HCCH) through email, which is an inefficient way to store and manage information of each complaint. Tracking down the list of requests is also an issue. For the goals to ensure the achievements of expanding to new clients, IT support needs a better alternative way to manage, store, and retrieve information. This thesis reports a prototype of a complaint management system implemented for the Healthcare center Helsingborg Hjärtat. The software architect pattern in this project is Model view control and applied on the Visual studio .Net core with the programming language of C-sharp and HTML. Test results showcase the prototype of the complaint management system as an administrator, and the result of the system handles the complaint cases well. The IT support experience keeps track of the complaints more efficiently sent from the client users.

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  • 5.
    Abiri, Najmeh
    et al.
    Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden.
    Linse, Björn
    Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden.
    Edén, Patrik
    Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden.
    Ohlsson, Mattias
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research. Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden.
    Establishing strong imputation performance of a denoising autoencoder in a wide range of missing data problems2019In: Neurocomputing, ISSN 0925-2312, E-ISSN 1872-8286, Vol. 65, p. 137-146Article in journal (Refereed)
    Abstract [en]

    Dealing with missing data in data analysis is inevitable. Although powerful imputation methods that address this problem exist, there is still much room for improvement. In this study, we examined single imputation based on deep autoencoders, motivated by the apparent success of deep learning to efficiently extract useful dataset features. We have developed a consistent framework for both training and imputation. Moreover, we benchmarked the results against state-of-the-art imputation methods on different data sizes and characteristics. The work was not limited to the one-type variable dataset; we also imputed missing data with multi-type variables, e.g., a combination of binary, categorical, and continuous attributes. To evaluate the imputation methods, we randomly corrupted the complete data, with varying degrees of corruption, and then compared the imputed and original values. In all experiments, the developed autoencoder obtained the smallest error for all ranges of initial data corruption. © 2019 Elsevier B.V.

  • 6.
    Aboelwafa, Mariam M. N.
    et al.
    Electronics and Communications Engineering Department, American University in Cairo, New Cairo, Egypt.
    Seddik, Karim G.
    Electronics and Communications Engineering Department, American University in Cairo, New Cairo, Egypt.
    Eldefrawy, Mohamed Hamdy
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Gadallah, Yasser
    Electronics and Communications Engineering Department, American University in Cairo, New Cairo, Egypt.
    Gidlund, Mikael
    Department of Information Systems and Technology, Mid Sweden University, Sundsvall, Sweden.
    A Machine-Learning-Based Technique for False Data Injection Attacks Detection in Industrial IoT2020In: IEEE Internet of Things Journal, ISSN 2327-4662, Vol. 7, no 9, p. 8462-8471Article in journal (Refereed)
    Abstract [en]

    The accelerated move toward the adoption of the Industrial Internet-of-Things (IIoT) paradigm has resulted in numerous shortcomings as far as security is concerned. One of the IIoT affecting critical security threats is what is termed as the false data injection (FDI) attack. The FDI attacks aim to mislead the industrial platforms by falsifying their sensor measurements. FDI attacks have successfully overcome the classical threat detection approaches. In this article, we present a novel method of FDI attack detection using autoencoders (AEs). We exploit the sensor data correlation in time and space, which in turn can help identify the falsified data. Moreover, the falsified data are cleaned using the denoising AEs (DAEs). Performance evaluation proves the success of our technique in detecting FDI attacks. It also significantly outperforms a support vector machine (SVM)-based approach used for the same purpose. The DAE data cleaning algorithm is also shown to be very effective in recovering clean data from corrupted (attacked) data. © 2014 IEEE.

  • 7.
    Abram, S.
    et al.
    University of Durham, Durham, United Kingdom & Leeds Beckett University, Leeds, United Kingdom.
    Pink, Sarah
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). RMIT University, Digital Ethnography Research Centre, Melbourne, VIC, Australia & Loughborough University, Schools of Design and Civil and Building Engineering, Loughborough, United Kingdom.
    Introduction: Mediating publics and anthropology2015In: Media, anthropology and public engagement / [ed] Sarah Pink & Simone Abram, New York: Berghahn Books, 2015, Vol. 9, p. 1-22Chapter in book (Refereed)
  • 8.
    Abuella, Mohamed
    et al.
    Halmstad University, School of Information Technology, Center for Applied Intelligent Systems Research (CAISR).
    Atoui, M. Amine
    Halmstad University, School of Information Technology, Center for Applied Intelligent Systems Research (CAISR).
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Center for Applied Intelligent Systems Research (CAISR).
    Johansson, Simon
    CetaSol AB, Gothenburg, Sweden.
    Faghani, Ethan
    CetaSol AB, Gothenburg, Sweden.
    Data-Driven Explainable Artificial Intelligence for Energy Efficiency in Short-Sea Shipping2023In: Machine Learning and Knowledge Discovery in Databases: Applied Data Science and Demo Track: European Conference, ECML PKDD 2023, Turin, Italy, September 18–22, 2023, Proceedings, Part VII / [ed] Gianmarco De Francisci Morales; Claudia Perlich; Natali Ruchansky; Nicolas Kourtellis; Elena Baralis; Francesco Bonchi, Cham: Springer, 2023, Vol. 14175, p. 226-241Conference paper (Refereed)
    Abstract [en]

    The maritime industry is under pressure to increase energy efficiency for climate change mitigation. Navigational data, combining vessel operational and environmental measurements from onboard instruments and external sources, are critical for achieving this goal. Short-sea shipping presents a unique challenge due to the significant influence of surrounding landscape characteristics. With high-resolution onboard data increasingly accessible through IoT devices, appropriate data representations and AI/ML analytical tools are needed for effective decision support. The aim of this study is to investigate the fuel consumption estimation model’s role in developing an energy efficiency decision support tool. ML models that lacking explainability may neglect important factors and essential constraints, such as the need to meet arrival time requirements. Onboard weather measurements are compared to external forecasts, and our findings demonstrate the necessity of eXplainable Artificial Intelligence (XAI) techniques for effective decision support. Real-world data from a short-sea passenger vessel in southern Sweden, consisting of 1754 voyages over 15 months (More of data description and code sources of this study can be found in the GitHub repository at https://github.com/MohamedAbuella/ST4EESSS), are used to support our conclusions.  © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

  • 9.
    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.

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  • 10.
    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). Halmstad University, School of Business, Innovation and Sustainability, The Rydberg Laboratory for Applied Sciences (RLAS). 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, 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.

  • 11.
    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.

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  • 12.
    Aderklou, Christina
    et al.
    Halmstad University, School of Health and Welfare.
    Fritzdorf, Liselott
    Halmstad University, School of Education, Humanities and Social Science, Centrum för lärande, kultur och samhälle (CLKS).
    Tebelius, Ulla
    Halmstad University, School of Health and Welfare, Centre of Research on Welfare, Health and Sport (CVHI).
    Bengtsson, Jeanette
    Halmstad University, School of Education, Humanities and Social Science, Centrum för lärande, kultur och samhälle (CLKS).
    Baerveldt, Albert-Jan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Pedatronics: Robotic toys as a source to evoke young girls’ technological interest2002In: 32nd Annual Frontiers in Education. Leading a Revolution in Engineering and Computer Science Education: Conference Proceedings Volume III - Saturday Sessions. Boston Park Plaza Hotel, Boston, Massachusetts, November 6-9, 2002, San Diego: Institute of Electrical and Electronics Engineers (IEEE), 2002, Vol. 2, p. F1C-19-F1C-24Conference paper (Refereed)
    Abstract [en]

    This paper presents some results within Pedatronics; a fusion between pedagogics and mechatronics. Our research interest is to study what emerges in the play with robotic toys. Field-experimental studies of 67 year old children’s purposeless play with robotic toys created a self-developmental sphere, as well as evoked young girl’s technological interest. Both girls and boys prolonged and intensified their interest according to the amount of gadgets involved. The results disclose a learning potential, indicating the importance to develop strategies at an early stage in order to encourage girls to choose technological and engineering educations. The study recommend engineers and toy designers, in cooperation with children, to move towards ’Integrated Play Systems’. Due to an ethological method, the results differ from other studies of children’s play with technological advanced artefacts. © 2002 IEEE

  • 13.
    Adiyodi Madhavan, Resmi
    et al.
    Halmstad University, School of Information Technology.
    Sajan, Ann Zenna
    Halmstad University, School of Information Technology.
    Malicious Activity Detection in Encrypted Network Traffic using A Fully Homomorphic Encryption Method2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Everyone is in need for their own privacy and data protection, since encryption transmission was becoming common. Fully Homomorphic Encryption (FHE) has received increased attention because of its capability to execute calculations over the encoded domain. Through using FHE approach, model training can be properly outsourced. The goal of FHE is to enable computations on encrypted files without decoding aside from the end outcome. The CKKS scheme is used in FHE.Network threats are serious danger to credential information, which enable an unauthorised user to extract important and sensitive data by evaluating the information of computations done on raw data. Thus the study provided an efficient solution to the problem of privacy protection in data-driven applications using Machine Learning. The study used an encrypted NSL KDD dataset. Machine learning-based techniques have emerged as a significant trend for detecting malicious attack. Thus, Random Forest (RF) is proposed for the detection of malicious attacks on Homomorphic encrypted data in the cloud server. Logistic Regression (LR) machine learning model is used to predict encrypted data on cloud server. Regardless of the distributed setting, the technique may retain the accuracy and integrity of the previous methods to obtain the final results.

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  • 14.
    Adnan Abdu, Jihad
    et al.
    Halmstad University, School of Information Technology.
    Lundström, Philip
    Halmstad University, School of Information Technology.
    Water Quality Device: Testing Through Electronic Measurements2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Water is the source of all life, but unfortunately, the water quality is getting only worse due to many factors like overuse, contamination, indifference and even by nature itself. By identifying the problem, we are one step closer to solving the problem, and that is why an intelligent water quality device is required to examine water and detect impurities within it. In this project, we are developing a device that uses an entirely new method to measure water quality. Even though the theory behind the device is very advanced, the device is still primitive in its functions and needs development to increase the usefulness and accuracy of the measurements!

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  • 15.
    Ads, Khaled
    Halmstad University, School of Information Technology.
    Field uniformity and isotropy investigation of Halmstad University's reverberation chamber: In collaboration with Halmstad University and Ericsson AB, Lund2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is the final module of the Master's program in Electronics Design at Halmstad University. The Master Thesis work is a part of an ongoing development of Halmstad University's reverberation chamber (RC), which is aimed at frequencies in the low GHz range. The development process has been passing in several phases. One phase is to design a mechanical stirrer system which was done by the work presented in another thesis work. The current phase, which is done by this thesis work, is to investigate electromagnetic field uniformity and isotropy while using tuned-mode (stepped stirrer). The frequency 2.4 GHz was chosen because, from one hand, it fits the capability of the assigned equipment for this thesis (spectrum analyzer, signal generator, antennas). On the other hand, it is the operating frequency of a wide range of WIFI and BlueTooth devices that need to be tested inside the RC to comply with the Electromagnetic Compatibility (EMC) standards. The measurement results verified, to a reasonable extent, the field uniformity and isotropy. The standard deviation of all measurements, taken from different eight positions with three different orientations of the receiving antenna, was 1.5dB. It is less than 3dB fulfilling the IEC 61000-4-21standards for frequencies above 400MGHz. Moreover, a quality factor degradation test was conducted, showing a 3.5 dB reduction of the received power when the chamber was loaded by organic material. The received power, while sweeping the bandwidth 800MHz-1.5GHz, was measured. These results indicate that at the resonance frequencies of the chamber, the received power is higher than that at non-resonance frequencies.

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  • 16.
    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.
    Library of actions: Implementing a generic robot execution framework by using manipulation action semantics2019In: 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.

  • 17.
    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

  • 18.
    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.

  • 19.
    Afram, Abboud
    et al.
    Halmstad University, School of Information Technology.
    Sarab Fard Sabet, Danial
    Halmstad University, School of Information Technology.
    Company Intranet2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many companies use intranets where only authorized personnel can share, create, and access news, events, and knowledge in a company. An intranet is a web application with dynamic content. It consists of various functions and features that facilitate the information management and knowledge flow within the company. The main goal of this project is to create and design an intranet demo that is adaptable and extendable by companies and organizations. The intranet contains various primary functions that users can interact with. The designed intranet is based on the EPiServer Content Management System framework and is programmed in back-end and front-end with the Visual Studio IDE tool. The back- end part is mainly programmed in C# language to create functions and logic such as the intranet structure and then linked to the front-end part where the HTML, CSS, and JavaScript library React is used to encode the front-end and get a user interface. The finalized intranet contains various primary functions where authorized employees have individual profiles with their status and contact information. Users can share corporate events and access corporate news.

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  • 20.
    Afram, Abboud
    et al.
    Halmstad University, School of Information Technology.
    Sarab Fard Sabet, Danial
    Halmstad University, School of Information Technology.
    Exploring State-of-the-Art Machine Learning Methods for Quantifying Exercise-induced Muscle Fatigue2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Muscle fatigue is a severe problem for elite athletes, and this is due

    to the long resting times, which can vary. Various mechanisms can

    cause muscle fatigue which signifies that the specific muscle has

    reached its maximum force and cannot continue the task. This thesis

    was about surveying and exploring state-of-the-art methods and

    systematically, theoretically, and practically testing the applicability

    and performance of more recent machine learning methods on an existing

    EMG to muscle fatigue pipeline. Several challenges within the

    EMG domain exist, such as inadequate data, finding the most suitable

    model, and how they should be addressed to achieve reliable

    prediction. This required approaches for addressing these problems

    by combining and comparing various state-of-the-art methodologies,

    such as data augmentation techniques for upsampling, spectrogram

    methods for signal processing, and transfer learning to gain a reliable

    prediction by various pre-trained CNN models.

    The approach during this study was to conduct seven experiments

    consisting of a classification task that aims to predict muscle fatigue

    in various stages. These stages are divided into 7 classes from 0-6, and

    higher classes represent a fatigued muscle. In the tabular part of the

    experiments, the Decision Tree, Random Forest, and Support Vector

    Machine (SVM) were trained, and the accuracy was determined. A

    similar approach was made for the spectrogram part, where the signals

    were converted to spectrogram images, and with a combination

    of traditional- and intelligent data augmentation techniques, such as

    noise and DCGAN, the limited dataset was increased. A comparison

    between the performance of AlexNet, VGG16, DenseNet, and InceptionV3

    pre-trained CNN models was made to predict differences in

    jump heights.

    The result was evaluated by implementing baseline classifiers on

    tabular data and pre-trained CNN model classifiers for CWT and

    STFT spectrograms with and without data augmentation. The evaluation

    of various state-of-the-art methodologies for a classification

    problem showed that DenseNet and VGG16 gave a reliable accuracy

    of 89.8 % on intelligent data augmented CWT images.

    The intelligent data augmentation applied on CWT images allows

    the pre-trained CNN models to learn features that can generalize unseen

    data. Proving that the combination of state-of-the-art methods

    can be introduced and address the challenges within the EMG domain.

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  • 21.
    Afzal, Wahaj
    Halmstad University, School of Information Technology, Center for Applied Intelligent Systems Research (CAISR).
    A Rule-based approach for detection of spatial object relations in images2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Deep learning and Computer vision are becoming a part of everyday objects and machines. Involvement of artificial intelligence in human’s daily life open doors to new opportunities and research. This involvement provides the idea of improving upon the in-hand research of spatial relations and coming up with a more generic and robust algorithm that provides us with 2-D and 3-D spatial relations and uses RGB and RGB-D images which can help us with few complex relations such as ‘on’ or ‘in’ as well. Suggested methods are tested on the dataset with animated and real objects, where the number of objects varies in every image from at least 4 to at most 10 objects. The size and orientation of objects are also different in every image.  

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  • 22.
    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.

  • 23.
    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.

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  • 24.
    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.

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  • 25.
    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)
  • 26.
    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.

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  • 27.
    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.

  • 28.
    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.

  • 29.
    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.

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  • 30.
    Aghaeipour, Mahtab
    et al.
    Solid State Physics and NanoLund, Lund University, Lund, Sweden.
    Pettersson, Håkan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Enhanced optical absorption in nanowires over a desire range of wavelengths2017In: MOC2017 : technical digest of the Twenty-Second Microoptics Conference: November 19-22, 2017, Institute of Industrial Science, The University of Tokyo, Japan, IEEE, 2017, Vol. 2017-November, p. 360-361Conference paper (Refereed)
    Abstract [en]

    Engineering optical absorption in nanowires, over a desire range of wavelengths is of importance to design high-performance nanowire-based photovoltaics. To this end, we integrate the nanowires with distributed Bragg reflectors to enhance absorption spectra of the nanowires and relate the consequent enhancement to increasing the optical path lengths of the modes. © 2017 The Japan Society of Applied Physics.

  • 31.
    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.

  • 32.
    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, 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.

  • 33.
    Aghanavesi, Somayeh
    et al.
    School of Technology and Business Studies, Dalarna University, Falun 78188, Sweden.
    Fleyeh, Hasan
    School of Technology and Business Studies, Dalarna University, Falun 78188, Sweden.
    Dougherty, Mark
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Feasibility of Using Dynamic Time Warping to Measure Motor States in Parkinson’s Disease2020In: Journal of Sensors, ISSN 1687-725X, E-ISSN 1687-7268, p. 1-14, article id 3265795Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to investigate the feasibility of using the Dynamic Time Warping (DTW) method to measure motor states in advanced Parkinson's disease (PD). Data were collected from 19 PD patients who experimented leg agility motor tests with motion sensors on their ankles once before and multiple times after an administration of 150% of their normal daily dose of medication. Experiments of 22 healthy controls were included. Three movement disorder specialists rated the motor states of the patients according to Treatment Response Scale (TRS) using recorded videos of the experiments. A DTW-based motor state distance score (DDS) was constructed using the acceleration and gyroscope signals collected during leg agility motor tests. Mean DDS showed similar trends to mean TRS scores across the test occasions. Mean DDS was able to differentiate between PD patients at Off and On motor states. DDS was able to classify the motor state changes with good accuracy (82%). The PD patients who showed more response to medication were selected using the TRS scale, and the most related DTW-based features to their TRS scores were investigated. There were individual DTW-based features identified for each patient. In conclusion, the DTW method can provide information about motor states of advanced PD patients which can be used in the development of methods for automatic motor scoring of PD. © 2020 Somayeh Aghanavesi et al.

  • 34.
    Agnoletto, Daniel
    et al.
    Institute of Informatics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
    Jonsson, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Pignaton de Freitas, Edison
    Institute of Informatics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
    Time slot transmission scheme with packet prioritization for Bluetooth low energy devices used in real-time applications2020In: International Journal of Wireless Information Networks, ISSN 1068-9605, E-ISSN 1572-8129, Vol. 27, no 4, p. 518-534Article in journal (Refereed)
    Abstract [en]

    Bluetooth Low Energy (BLE) is one of the most important technologies that feed the growing field of Internet of Things and Wireless Sensor Networks. Due to its flexibility and unique low power-consumption, an increasing number of industrial devices, household appliances and wearables are being designed using it. However, the real-time demands of these networks such as timing and Quality of Service are not fully covered by the protocol itself. To help improve and offer some control over these characteristics, this paper presents a time slot transmission scheme with packet prioritization. It is based on the division and allocation of the connection interval to two types of messages: real-time and ordinary. The goal is to offer the lowest packet loss and time guarantees for real-time messages, while providing acceptable throughput for ordinary ones. Since the probability of a BLE connection to close increases with the number of packets sent through it, the position where a real-time packet is being sent as well as the number of ordinary messages in a connection represent key factors. The use of the first and last slot for real-time packets with ordinary flow restricted to the space between them decreases the transmission delay uncertainty and allows probability tuning based on the number of ordinary messages. Simulations were performed using the proposed scheme and a reduction of more than 100 times in the delay variance was observed for real-time transmissions. Regarding reliability, around 5% of the packets were lost for a bit error rate of 10−3. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.

  • 35.
    Agvall, Björn
    et al.
    Halland Hospital Halmstad, Halmstad, Sweden.
    Ashfaq, Awais
    Halmstad University, School of Information Technology.
    Bjurström, Karl
    Halland Hospital Halmstad, Halmstad, Sweden.
    Etminani, Kobra
    Halmstad University, School of Information Technology.
    Friberg, Lovisa
    AstraZeneca, Stockholm, Sweden.
    Lidén, Johanna
    AstraZeneca, Stockholm, Sweden.
    Lingman, Markus
    Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Halland Hospital, Region Halland, Halmstad, Sweden.
    Characteristics, management and outcomes in patients with CKD in a healthcare region in Sweden: a population-based, observational study2023In: BMJ Open, E-ISSN 2044-6055, Vol. 13, no 7, article id e069313Article in journal (Refereed)
    Abstract [en]

    Objectives: To describe chronic kidney disease (CKD) regarding treatment rates, comorbidities, usage of CKD International Classification of Diseases (ICD) diagnosis, mortality, hospitalisation, evaluate healthcare utilisation and screening for CKD in relation to new nationwide CKD guidelines.

    Design: Population-based observational study.

    Setting: Healthcare registry data of patients in Southwest Sweden.

    Participants: A total cohort of 65 959 individuals aged >18 years of which 20 488 met the criteria for CKD (cohort 1) and 45 470 at risk of CKD (cohort 2).

    Primary and secondary outcome measures: Data were analysed with regards to prevalence, screening rates of blood pressure, glucose, estimated glomerular filtration rate (eGFR), Urinary-albumin-creatinine ratio (UACR) and usage of ICD-codes for CKD. Mortality and hospitalisation were analysed with logistic regression models.

    Results: Of the CKD cohort, 18% had CKD ICD-diagnosis and were followed annually for blood pressure (79%), glucose testing (76%), eGFR (65%), UACR (24%). UACR follow-up was two times as common in hypertensive and cardiovascular versus diabetes patients with CKD with a similar pattern in those at risk of CKD. Statin and renin-angiotensin-aldosterone inhibitor appeared in 34% and 43%, respectively. Mortality OR at CKD stage 5 was 1.23 (CI 0.68 to 0.87), diabetes 1.20 (CI 1.04 to 1.38), hypertension 1.63 (CI 1.42 to 1.88), atherosclerotic cardiovascular disease (ASCVD) 1.84 (CI 1.62 to 2.09) associated with highest mortality risk. Hospitalisation OR in CKD stage 5 was 1.96 (CI 1.40 to 2.76), diabetes 1.15 (CI 1.06 to 1.25), hypertension 1.23 (CI 1.13 to 1.33) and ASCVD 1.52 (CI 1.41 to 1.64).

    Conclusions: The gap between patients with CKD by definition versus those diagnosed as such was large. Compared with recommendations patients with CKD have suboptimal follow-up and treatment with renin-angiotensin-aldosterone system inhibitor and statins. Hypertension, diabetes and ASCVD were associated with increased mortality and hospitalisation. Improved screening and diagnosis of CKD, identification and management of risk factors and kidney protective treatment could affect clinical and economic outcomes. © Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

  • 36.
    Ahl, Josefin
    et al.
    Halmstad University, School of Information Technology.
    Djurklou, Julia
    Halmstad University, School of Information Technology.
    Ransomware-hotet mot svenska sjukhus: – en intervju- och litteraturstudie2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Statistics show an increase in ransomware activity in recent years. The increase is mainly due to the ongoing Covid-19 pandemic. Cybercriminals take advantage of the fact that hospitals worldwide are overloaded with caring for seriously ill patients in Covid-19 and perform ransomware attacks.

    This thesis examines how Swedish hospitals experience and handle the increased threat of ransomware. The bachelor’s thesis consists of a literature study and some in-depth interviews. The literature study is investigating ransomware as a phenomenon and finding out why it is a successful method for cybercriminals to use in digital extortion.

    The purpose is also to investigate how Swedish hospitals relate to the fact that the healthcare sector has become an attractive target for cyber-attacks. The interview study examines the hospitals' IT security to determine whether they are sufficiently resistant to ransomware attacks. The interview results are discussed and analyzed against the background of the literature. The conclusion of this analysis is the basis for the proposed countermeasure.

    The results show that the hospitals surveyed have suitable IT security. The most central security mechanisms for the hospitals are their backup and recovery routines in the fight against ransomware. The discussion in this work combines the results from the literature and interview studies carried out. Based on the discussion, the conclusion is that the hospitals surveyed have good security and meet most of the recommendations published by Swedish authorities. Still, there is room for some improvement which is indicated.

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  • 37.
    Ahlandsberg, Natalie
    et al.
    Halmstad University, School of Information Technology.
    Berntsson, Lisa
    Halmstad University, School of Information Technology.
    Cyberkrig under förstoringsglaset: En kvalitativ studie som utreder begreppet cyberkrig utifrån olika aspekter samt delger privata och statliga aktörers perspektiv på området.2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In an increasingly digitalized world, the virtual reality is becoming as significant as the physical one. Sweden is at the forefront of digitalization, but at the same time, it is slipping behind in cybersecurity. Together, this may mean that warfare also can occur in virtual reality. The concept of cyberwarfare has received increased attention in Swedish media; however, it has become clear that the concept does not have a definition in Sweden. What are the reasons behind this, how can cyberwarfare be alternatively defined, and how does the concept of cyberwarfare relate to Swedish authorities’ defense work in an increasingly digitalized world?

    This qualitative study aims to investigate these questions by sharing the perspectives of private and state actors to contribute to a deeper understanding of the concept of cyberwarfare. This study’s literature and article study, as well as semi-structured interviews, provide an opportunity to examine individuals’ perspectives and other material such as doctrines and reports from various authorities in Sweden and internationally.

    Based on the results of this work, it is concluded that the concept of cyberwarfare is used in the public sphere, but not in a formal context and among state actors. State actors such as the Swedish Armed Forces, MSB, and FOI prefer to use the concept of cyberoperations. Another concept that has proved to be fundamental to creating an understanding of the concept of cyber war is the cyber domain. The authors of this study have defined cyberwarfare as when “a nation or organization in the cyber domain attacks or attempts to damage the digital infrastructure of another nation. The consequences must be equivalent to an armed attack following Article 2(4) of the UN Charter”. 

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  • 38.
    Ahlbäck, Joel
    et al.
    Halmstad University, School of Information Technology.
    Jalking, Jesper
    Halmstad University, School of Information Technology.
    Logistikföretag i försörjningskedjan: Rekommendationer till logistikföretag i hanteringen av informationssäkerhet2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Information security is an important aspect when running a business. Before, information security has been separated to the business area of IT. But lately this issue has broadened and become an important part of business-activity. This has resulted in a growing interest among business leaders. Literature within the subject information security mainly focuses on how organizations maintain safe systems and protect themselves from cyber-attacks and information infringements. Existing literature identifies new security threats that have emerged after advances in internet technology, but little is known about how these threats can be managed. Researchers request research on how cooperation in supply chains poses risks to secure information management. Logistics companies provide customers with logistics services such as warehouse management, transport, order processing and packaging. Logistics companies are a central node in supply chains. They often participate in several supply chains in different industries. The extensive interconnection of companies poses a security risk. It also means that logistics companies can be seen as targets for cyber-attacks. The purpose of the study has therefore been to create an understanding of the challenges logistics companies face in managing information security in the supply chain.

     

    The research question has been answered by interviewing representatives from logistics organizations. The empirical data has undergone a thematic analysis. The results of the study show that the management of information security varies between companies. The study’s conclusions present recommendations. The recommendations describe how logistics companies can manage information security in the supply chain.

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  • 39.
    Ahlman, Adam
    et al.
    Halmstad University, School of Information Technology.
    Taylor, Adam
    Halmstad University, School of Information Technology.
    Dataset characteristics effect on time series forecasting: comparison of statistical and deep learning models2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Time series are points of data measured throughout time in equally spaced periods. They present characteristics such as level, noise, trend, seasonality, and outliers. Time series forecasting is the attempt to predict single or multiple future values. It holds significant relevance in numerous fields,including, but not limited to, healthcare, finance, and weather forecasting. It has recently gained more attention due to the COVID-19 pandemic, which highlighted the importance of predicting and managing crises. Two distinct methods of forecasting utilise either statistical or deep learning models, and the debate about the best model is still inconclusive. This thesis aimed to explicate the benefits and drawbacks of each approach pertaining to singlestep and multi-step forecasting. The study applied four models, two of each method, on datasets of varying characteristics and measured their prediction accuracy and computing time. The prediction accuracy of each model was measured using commonly used evaluation metrics, including Root MeanSquare Error. Subsequently, the results were compared with the features of the datasets to identify possible interconnecting relations between the factors. The findings concluded that the deep learning models generally produced a more accurate prediction but required more processing power and computing time. Contrastingly, the statistical models' predictions were less accurate butmarginally faster. Furthermore, the forecast accuracy's most impactful characteristics were the dataset's trend and linearity. The code and datasets were published at: https://github.com/Adam20Taylor/BScThesis

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  • 40.
    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.

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  • 41.
    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.

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  • 42.
    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. 

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  • 43.
    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

  • 44.
    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.

  • 45.
    Airout, Fadi
    et al.
    Halmstad University, School of Information Technology.
    Mardini, Najmeddin
    Halmstad University, School of Information Technology.
    Combolt (Bluetooth Integrering)2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work is about developing an existing product in a company. The productis AnyBus Communicator used to connect two serial devices with differentindustrial network interfaces. The development involves combining theexisting product with a BLE-module and an antenna. Wireless technologyopens up various possibilities and plays a significant role in complexenvironments. Today, communication occurs through an Ethernet cable. Theproject's goal is to design a circuit for the BLE-module integrated into theproduct's PCB. The goal also includes presenting a choice of antenna and aplastic-type for antenna enclosure that can be used in future development ofthe product. The work began with the evaluation of the BLE-module, wherea communication test was performed to test the BLE-module's properties.Several tests were performed using Network Analyzer to select a suitableantenna from three different antennas. The antennas were tested with twodifferent types of plastic designed using Solidworks, to present a choice ofthe type of plastic to be used during all tests in the development process.Presenting an electrical schematic and PCB for the wireless AnyBusCommunicator was a goal of the project. Since it was impossible to combinethe BLE-module with the product in the same PCB, it was decided to designa separate circuit that illustrates how the BLE-module will be connected tothe product in the future. The project resulted in a proposal for both an antennaand a plastic-type. A prototype circuit has also been designed for the BLEmodule. The choice of antenna and plastic-type was based on the best valuewhen measuring return loss values. The type of plastic chosen will not be usedin the finished product but is a way to test antenna functionality against 3Dprinted plastics. This is considered to be a cheaper solution that gives a similarresult compared to the enclosure used in the product. A finished design of thecircuit board has been implemented. However, it could not be tested due tothe company having a difficult situation to produce ordinary circuit.Therefore, it can be concluded that the work had relevant proposals and wasa forward step in the development process.

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  • 46.
    Ak, Abdullah Cihan
    et al.
    Istanbul Technical University, Istanbul, Turkey.
    Aksoy, Eren
    Halmstad University, School of Information Technology.
    Sariel, Sanem
    Istanbul Technical University, Istanbul, Turkey.
    Learning Failure Prevention Skills for Safe Robot Manipulation2023In: IEEE Robotics and Automation Letters, E-ISSN 2377-3766, Vol. 8, no 12, p. 7994-8001Article in journal (Refereed)
    Abstract [en]

    Robots are more capable of achieving manipulation tasks for everyday activities than before. However, the safety of manipulation skills that robots employ is still an open problem. Considering all possible failures during skill learning increases the complexity of the process and restrains learning an optimal policy. Nonetheless, safety-focused modularity in the acquisition of skills has not been adequately addressed in previous works. For that purpose, we reformulate skills as base and failure prevention skills, where base skills aim at completing tasks and failure prevention skills aim at reducing the risk of failures to occur. Then, we propose a modular and hierarchical method for safe robot manipulation by augmenting base skills by learning failure prevention skills with reinforcement learning and forming a skill library to address different safety risks. Furthermore, a skill selection policy that considers estimated risks is used for the robot to select the best control policy for safe manipulation. Our experiments show that the proposed method achieves the given goal while ensuring safety by preventing failures. We also show that with the proposed method, skill learning is feasible and our safe manipulation tools can be transferred to the real environment © 2023 IEEE

  • 47.
    Akbari, Maryam
    et al.
    Iran University of Science and Technology, Tehran, Iran.
    Mirzakuchaki, Sattar
    Iran University of Science and Technology, Tehran, Iran.
    Fazeli, Mahdi
    Halmstad University, School of Information Technology.
    Tarihi, Mohammad Reza
    Niroo Research Institute, Tehran, Iran.
    Pure Magnetic Memory-Based PUFs: A Secure and Lightweight Solution for IoT Devices2023In: Iranian Journal of Electrical and Electronic Engineering, ISSN 2383-3890, Vol. 19, no 4, article id 2944Article in journal (Refereed)
    Abstract [en]

    In light of the growing prevalence of Internet of Things (IoT) devices, it has become essential to incorporate cryptographic protection techniques for high-security applications. Since IoT devices are resource-constraints in terms of power and area, finding cost-effective ways to enhance their security is necessary. Physical unclonable function (PUF) is considered a trusted hardware security mechanism that generates true and intrinsic randomness by extracting the inherent process variations of circuits. In this paper, a novel pure magnetic memory-based PUF is presented. The fundamental building blocks of the proposed PUF design are magnetic devices, the so-called mCells. These magnetoresistive devices exclusively utilize Magnetic Tunnel Junction (MTJ) components. Using purely MTJ in the main memory and sense amplifier in the proposed PUF leads to high randomness, high reliability, low power, and ultra-compact occupation area. The Monte Carlo HSPICE simulation results demonstrate that the proposed PUF achieves a uniqueness of 49.89%, uniformity of 50.02 %, power consumption of 1.43 µW, and an area occupation of 0.01 µm2 per bit. © 2023, Iran University of Science and Technology. All rights reserved.

  • 48.
    Akbari, Maryam
    et al.
    Iran University of Science and Technology, Tehran, Iran.
    Mirzakuchaki, Sattar
    Iran University of Science and Technology, Tehran, Iran.
    Jamshidi, Vahid
    Shahid Bahonar University of Kerman, Kerman, Iran.
    Fazeli, Mahdi
    Halmstad University, School of Information Technology.
    Tarihi, Mohammad Reza
    Niroo Research Institute (NRI), Tehran, Iran.
    An Ultra-compact Pure Magnetic Arbiter PUF with High Reliability and Low Power Consumption2023In: IEEE transactions on nanotechnology, ISSN 1536-125X, E-ISSN 1941-0085, Vol. 22, p. 449-456Article in journal (Refereed)
    Abstract [en]

    Due to the rugged environmental factors in IoT applications and constrained on-chip resources, PUF, as a critical hardware primitive, is a promising solution for key storage, authentication, and ID generation. The existing CMOS-based Arbiter PUFs mainly suffer from low reliability and vulnerability against modeling attacks. In this paper, the proposed PUF utilizes mCell devices, a class of Magnetoresistive devices employing only Magnetic Tunnel Junction (MTJ) devices, as a building block. Also, a novel nonvolatile latch is proposed to act as an arbiter and generates the responses by comparing the current values instead of delays which leads to increased the reliability by subtracting the constant variation rates of MTJs under environmental variation without adding hardware overhead. The characteristics of MTJ like nonvolatility, stochastic switching, chaotic magnetization, low power consumption, and low occupied area have made the proposed PUF to a low power, highly reliable, high randomness and ultra-compact pure magnetic arbiter PUF. The Monte Carlo HSPICE simulation results reveal that the uniformity, uniqueness, bit-aliasing, power consumption, and area of the proposed PUF are 49.24 %, 49.87 %, 48.64 %, 10.771 μW and 0.106 μm2, respectively. In addition, the average BER across a wide temperature range (-50C 150C) and voltage range (0.05 V-0.1 V) is 0.08 % and 0.18 %, respectively. © IEEE

  • 49.
    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.

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  • 50.
    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.

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