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  • 151.
    Andreasson, Samuel
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Palmér, Jesper
    Högskolan i Halmstad, Akademin för informationsteknologi.
    OPC UA Field eXchange Prototyping: Enabling decentralized communication using Publish/Subscribe2021Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Open Platform Communication Unified Architechure, eller OPC UA, är ett av de världsledande kommunikationsprotokoll som är specialiserat i att förena kommunikation i produktionssystem. 2018 startade OPC Foundation, ett industriellt konsortium, ett initiativ vid namn OPC UA Field eXchange med målet att utvekcla det nuvarande protokollet så att det kan användas till kommunikation på låg nivå, exempelvis mellan sensorer och ställdon. Denna rapport utforskar ifall det är möjligt att utveckla protokollet och integrera det i HMS Networks modul AnyBus CompactCom 40. 

    Problemformluleringen baseras på framtida behov hos fabriker relaterat till automatisering. För att konkurrera framöver behöver fabriker anpassa sig till utvecklingen inom automatisering. OPC UA FX fokuserar på decentralierad kommunikation mellan enheter som fältanordning, maskin och moln samtidigt för att belastningen ska delas upp över hela systemet. Samtidigt som enheter i industiella nätverket fritt ska kunna överföra data mellan varandra oberoende vilken tillverkare som skapat enheten.  

    Syftet med arbetet är att, baserat på Open62541, utveckla PubSub teknologi med metoder som möjlighetsgör att två eller fler instanser av en FX applikation ska kunna transportera data genom att prenumerera på och publicera data samtidigt. När mjukvaran fungerar är tanken att integrera mjukvaran på en AnyBus CompactCom 40 modul för att bevisa att implementationen är möjlig i ett praktiskt sammanhang. 

    Open62541 används för att inkludera nödvändiga OPC UA bibliotek, funktionalitet och datatyper. Protokollet utvecklas i C i en VisualStudio miljö och integreras med hjälp av Eclipse.

    Resultatet i form av mjukvara var en kopplings intriktat data utbyte, baserad på OPC UA information modell, där en eller två instanser av ett program kan publicera och prenumerera på data samtidigt. HMS Networks kan använda resultatet i arbetet att implementera OPC UA FX i deras produkter.

    ​Sammanfattningsvis är Open62541 ett mycket användbart verktyg för utvekcling av OPC UA protokol. Dessvärre lyckades inte integrationen av mjukvaran i CompactCom modulen helt och hållet, men det som åstadkommits i arbetet kan i hög grad användas för fortsatt utveckling av OPC UA FX i HMS Networks produkter.

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  • 152.
    Andreev, Sergey D.
    et al.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Turlikov, Andrey M.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Performance analysis of a high-speed ultra-wideband WPAN MAC2007Ingår i: Proceedings of the 14th International Conference on Analytical and Stochastic Modelling Techniques and Applications: 4 - 6 June 2007, Prague, Czech Republic ; ASMTA 2007 / [ed] Khalid Al-Begain, Armin Heindl & Miklos Telek, Sbr.-Dudweiler: Digitaldruck Pirrot GmbH , 2007, s. 44-49Konferensbidrag (Refereegranskat)
    Abstract [en]

    The current paper addresses the problem of the throughput-delay performance of a contemporary WPAN MAC standard. A brief overview of the standard functionality is first presented that allows a system model derivation. Two different acknowledgement policies are described under which the channel operation is considered. Two possible input traffic models are also considered one of them being saturation conditions under which the performance analysis is done that is further verified by means of the simulation. The obtained results show the system behavior as the number of channel users increase and allow the tuning of the protocol parameters to improve the performance.

  • 153.
    Andreev, Sergey D.
    et al.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Performance analysis and enhancement of an ultra-wideband WPAN MAC in the presence of noise2007Ingår i: XI International Symposium on Problems of Redundancy in Information and Control Systems, Saint Petersburg, 2007, s. 117-122Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper addresses the performance evaluation of the contemporary UWB WPAN standard. The basic standard functionality is described for which a system model is derived that accounts for the possible errors due to the background noise. Two realistic scenarios of the saturation conditions and the Bernoulli packet arrivals are considered to calculate the system throughput and the mean initial packet delay. The redundancy-based error detection mechanism that is implemented in the standard is discussed that allows the enhancement of the system performance. The obtained results are compared against the simulation which shows a good accordance with the analytical results and a distinct superiority of the introduced enhancement.

  • 154.
    Andreev, Sergey
    et al.
    Department of Communications Engineering, Tampere University of Technology, Tampere, Finland.
    Galinina, Olga
    Speech Technology Center, St. Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg Institute for Informatics and Automation, Russian Academy of Sciences, St. Petersburg, Russia.
    Cross-Layer Channel-Aware Approaches for Modern Wireless Networks2010Konferensbidrag (Refereegranskat)
  • 155.
    Andreev, Sergey
    et al.
    Department of Communications Engineering, Tampere University of Technology, Finland.
    Galinina, Olga
    Department of Communications Engineering, Tampere University, Finland of Technology.
    Vinel, Alexey
    Department of Communications Engineering, Tampere University, Finland of Technology.
    Performance Evaluation of a Three Node Client Relay System2011Ingår i: International Journal of Wireless Networks and Broadband Technologies, ISSN 2155-6261, Vol. 1, nr 1, s. 73-84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, the authors examine a client relay system comprising three wireless nodes. Closed-form expressions for mean packet delay, as well as for throughput, energy expenditure, and energy efficiency of the source nodes are also obtained. The precision of the established parameters is verified by means of simulation.

  • 156.
    Andreev, Sergey
    et al.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Saffer, Zsolt
    Budapest University of Technology and Economics, Budapest, Hungary.
    Turlikov, Andrey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg Institute for Informatics and Automation, Russian Academy of Sciences, Saint-Petersburg, Russia.
    Overall Delay in IEEE 802.16 with Contention-Based Random Access2009Ingår i: / [ed] K. Al Begain, D. Fiems, G. Horvath, Heidelberg: Springer, 2009, s. 89-102Konferensbidrag (Refereegranskat)
  • 157.
    Andreev, Sergey
    et al.
    Department of Communications Engineering, Tampere University of Technology, Tampere, Finland.
    Saffer, Zsolt
    Budapest University of Technology and Economics, Budapest, Hungary.
    Turlikov, Andrey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg Institute for Informatics and Automation, Russian Academy of Sciences, Saint-Petersburg, Russia.
    Upper Bound on Overall Delay in Wireless Broadband Networks with Non Real-Time Traffic2010Konferensbidrag (Refereegranskat)
  • 158.
    Andreev, Sergey
    et al.
    St. Petersburg State University of Aerospace Instrumentation, Bolshaya Morskaya street, 67, 190000, St. Petersburg, Russian Federation.
    Turlikov, Andrey
    St. Petersburg State University of Aerospace Instrumentation, Bolshaya Morskaya street, 67, 190000, St. Petersburg, Russian Federation.
    Vinel, Alexey
    St. Petersburg State University of Information Technologies, Mechanics and Optics, Vasilievsky Island, Birjevaja Linija, 4, 199034, St. Petersburg, Russian Federation.
    Contention-Based Polling Efficiency in Broadband Wireless Networks2008Ingår i: Analytical and Stochastic Modeling Techniques and Applications: 15th International Conference, ASMTA 2008 Nicosia, Cyprus, June 4-6, 2008 Proceedings / [ed] Khalid Al-Begain, Armin Heindl, Miklós Telek, Berlin: Springer Berlin/Heidelberg, 2008, s. 295-309Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper addresses the performance of the contention-based polling techniques at the bandwidth reservation stage of IEEE 802.16 standard. A general proposition is proved, which establishes that the grouping of users in the random multiple access system does not change its capacity. Broadcast and multicast polling mechanisms are then considered, for which the throughput and the rate of the truncated binary exponential backoff algorithm are calculated for the lossy and the lossless system types, respectively. It is shown, that subject to proper optimization the performance of the aforementioned algorithm is the same for both system types. The efficiency of the symmetric user grouping is finally studied, which demonstrates that a negligible performance gain may be achieved for the cost of the increased IEEE 802.16 overhead.

  • 159.
    Andreev, Sergey
    et al.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Turlikov, Andrey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg Institute for Informatics and Automation, Russian Academy of Sciences, Saint-Petersburg, Russia.
    Symmetric User Grouping for Multicast and Broadcast Polling in IEEE 802.16 Networks2008Ingår i: Selected Lectures on Multiple Access and Queueing Systems: Revised Selected Papers from International Workshop on Multiple Access Communications - MACOM-2008 (16-17 June 2008, Saint-Petersburg) / [ed] Vladimir Vishnevsky, Alexey Vinel, Yevgeni Koucheryavy & Dirk Staehle, Saint-Petersburg: Saint-Petersburg State University of Aerospace Instrumentation , 2008, s. 52-62Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we address the bandwidth reservation in IEEE 802.16 standard via multicast and broadcast polling mechanisms. It is shown that symmetric user grouping with the same QoS requirements does not change the capacity of the random multiple access system. Binary exponential backoff protocol is then investigated as it is standardized for both multicast and broadcast polling. We establish that symmetric user grouping does not essentially increase the performance of this protocol.

  • 160.
    Andreev, Sergey
    et al.
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Vinel, Alexey
    Saint-Petersburg State University of Aerospace Instrumentation, Saint-Petersburg, Russia.
    Gilbert-Elliot Model Parameters Derivation for the IEEE 802.11 Wireless Channel2007Ingår i: Distributed Computer and Communication Networks. Theory and Applications: Proceedings of the International Workshop. Vol.1. Moscow, Russia, September 10-12, 2007, Moscow: Institute for Information Transmission Problems (Kharkevich Institute) , 2007, s. 101-107Konferensbidrag (Refereegranskat)
  • 161.
    Angelsmark, Ola
    et al.
    Department of Computer Science, Lund University, Lund, Sweden.
    Malec, Jacek
    Department of Computer Science, Lund University, Lund, Sweden.
    Nilsson, Klas
    Department of Computer Science, Lund University, Lund, Sweden.
    Nowaczyk, Sławomir
    Department of Computer Science, Lund University, Lund, Sweden.
    Prosperi, Leonardo
    Department of Computer Science, Lund University, Lund, Sweden.
    Knowledge Representation for Reconfigurable Automation Systems2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    This article describes the work in progress on knowledge representation formalisms chosen for use in the European project SIARAS. Skill-Based Inspection and Assembly for Reconfigurable Automation Systems has a goal of creating intelligent support system for reconfiguration and adaptation of assembly systems. Knowledge is represented in an ontology expressed in OWL, for generic reasoning in Description Logic, and in a number of special-purpose reasoning modules, specific for the application domain.

  • 162.
    Antham, Karunakar
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Palle, Chandrashekar reddy
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Mantoor, Ashwin kumar
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Peer to Peer VoIP over IEEE 802.11 WLAN2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Voice over Internet Protocol (VoIP) over WLAN is one of the most important technologies in today’s world of communication. VoIP is simply a way to make phone calls through the internet because of the convergence of voice and data networks enables new applications and cost reductions. Voice over WLAN phones are already being offered to enterprises by leading vendors. Most of internet services or applications require centralized network to communicate, but with Ad-hoc networks there is no such requirement at all.

    In this report we have established a VoIP session by forming a network between Android mobile devices without using an Access point. Energy consumption is a major problem for VoIP over wireless LAN applications while using them in hand held devices. We investigated the energy consumption characteristics of our Evaluation kit during VoIP session. We further studied about new technology: “Wi-Fi Direct” which allows Wi-Fi equipped devices to share data without using wireless access points.

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  • 163.
    Antonelo, Eric Aislan
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Figueiredo, Maurício Fernandes
    Department of Computer Science, State University of Maringá, 87020-900, Maringá - PR, Brazil.
    Baerveldt, Albert Jan
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Calvo, Rodrigo A.
    Department of Computer Science and Statistics, University of São Paulo, São Carlos, Brazil.
    Intelligent autonomous navigation for mobile robots: Spatial concept acquisition and object discrimination2005Ingår i: 2005 IEEE International Symposium on Computational Intelligence in Robotics and Automation, Proceedings, New York: IEEE Press, 2005, s. 553-557Konferensbidrag (Refereegranskat)
    Abstract [en]

    An autonomous system able to construct its own navigation strategy for mobile robots is proposed. The navigation strategy is molded from navigation experiences (succeeding as the robot navigates) according to a classical reinforcement learning procedure. The autonomous system is based on modular hierarchical neural networks. Initially the navigation performance is poor (many collisions occur). Computer simulations show that after a period of learning the autonomous system generates efficient obstacle avoidance and target seeking behaviors. Experiments also offer support for concluding that the autonomous system develops a variety of object discrimination capability and of spatial concepts.

  • 164.
    Antony, Anchu
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Myladi Kelambath, Deepthi
    Högskolan i Halmstad, Akademin för informationsteknologi.
    LP_MQTT - A Low-Power IoT Messaging Protocol Based on MQTT Standard2024Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In the Internet of Things (IoT) era, the MQTT Protocol played a bigpart in increasing the flow of uninterrupted communication betweenconnected devices. With its functioning being on the publish/subscribe messaging system and having a central broker framework, MQTTconsidering its lightweight functionality, played a very vital role inIoT connectivity. Nonetheless, there are challenges ahead, especiallyin energy consumption, because the majority of IoT devices operateunder constrained power sources. In line with this, our research suggests how the MQTT broker can make an intelligent decision usingan intelligent algorithm. The algorithm idealizes wake-up times forsubscriber clients with the aid of previous data, including machinelearning (ML) regression techniques in the background that producesubstantial energy savings. The study combines the regression machine learning approaches with the quality of service levels’ incorporation into the decision framework through the introduction ofoperational modes designed for effective client management. The research, therefore, aims universally to enhance the efficiency availablein MQTT making it applicable across diverse IoT applications by simultaneously addressing both the broker and the client sides . Theversatile approach ensures more performance and sustainability forMQTT, further strengthening its build as one of the building blocksfor energy efficient and responsive communication in the IoT. Deeplearning approaches that follow regression will be the required leapfor the transformation of energy consumption and adoption of resource allocation within IoT networks to an optimization level thatwould unlock new frontiers of efficiency for a sustainable connectedfuture.

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  • 165.
    Aramrattana, Maytheewat
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Göteborg, Sweden.
    A Simulation-Based Safety Analysis of CACC-Enabled Highway Platooning2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Cooperative Intelligent Transport Systems (C-ITS) enable actors in the transport systems to interact and collaborate by exchanging information via wireless communication networks. There are several challenges to overcome before they can be implemented and deployed on public roads. Among the most important challenges are testing and evaluation in order to ensure the safety of C-ITS applications.

    This thesis focuses on testing and evaluation of C-ITS applications with regard to their safety using simulation. The main focus is on one C-ITS application, namely platooning, that is enabled by the Cooperative Adaptive Cruise Control (CACC) function. Therefore, this thesis considers two main topics: i) what should be modelled and simulated for testing and evaluation of C-ITS applications? and ii) how should CACC functions be evaluated in order to ensure safety?

    When C-ITS applications are deployed, we can expect traffic situations which consist of vehicles with different capabilities, in terms of automation and connectivity. We propose that involving human drivers in testing and evaluation is important in such mixed traffic situations. Considering important aspects of C-ITS including human drivers, we propose a simulation framework, which combines driving-, network-, and traffic simulators. The simulation framework has been validated by demonstrating several use cases in the scope of platooning. In particular, it is used to demonstrate and analyse the safety of platooning applications in cut-in situations, where a vehicle driven by a human driver cuts in between vehicles in platoon. To assess the situations, time-to-collision (TTC) and its extensions are used as safety indicators in the analyses.

    The simulation framework permits future C-ITS research in other fields such as human factors by involving human drivers in a C-ITS context. Results from the safety analyses show that cut-in situations are not always hazardous, and two factors that are the most highly correlated to the collisions are relative speed and distance between vehicles at the moment of cutting in. Moreover, we suggest that to solely rely on CACC functions is not sufficient to handle cut-in situations. Therefore, guidelines and standards are required to address these situations properly.

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  • 166.
    Aramrattana, Maytheewat
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Modelling and Simulation for Evaluation of Cooperative Intelligent Transport System Functions2016Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Future vehicles are expected to be equipped with wireless communication tech- nology, that enables them to be “connected” to each others and road infras- tructures. Complementing current autonomous vehicles and automated driving systems, the wireless communication allows the vehicles to interact, cooperate, and be aware of its surroundings beyond their own sensors’ range. Such sys- tems are often referred to as Cooperative Intelligent Transport Systems (C-ITS), which aims to provide extra safety, efficiency, and sustainability to transporta- tion systems. Several C-ITS applications are under development and will require thorough testing and evaluation before their deployment in the real-world. C- ITS depend on several sub-systems, which increase their complexity, and makes them difficult to evaluate.

    Simulations are often used to evaluate many different automotive appli- cations, including C-ITS. Although they have been used extensively, simulation tools dedicated to determine all aspects of C-ITS are rare, especially human fac- tors aspects, which are often ignored. The majority of the simulation tools for C-ITS rely heavily on different combinations of network and traffic simulators. The human factors issues have been covered in only a few C-ITS simulation tools, that involve a driving simulator. Therefore, in this thesis, a C-ITS simu- lation framework that combines driving, network, and traffic simulators is pre- sented. The simulation framework is able to evaluate C-ITS applications from three perspectives; a) human driver; b) wireless communication; and c) traffic systems.

    Cooperative Adaptive Cruise Control (CACC) and its applications are cho- sen as the first set of C-ITS functions to be evaluated. Example scenarios from CACC and platoon merging applications are presented, and used as test cases for the simulation framework, as well as to elaborate potential usages of it. Moreover, approaches, results, and challenges from composing the simulation framework are presented and discussed. The results shows the usefulness of the proposed simulation framework.

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  • 167.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). RISE Viktoria, Göteborg, Sweden.
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Safety Analysis of Cooperative Adaptive Cruise Control in Vehicle Cut-in Situations2017Ingår i: Proceedings of 2017 4th International Symposium on Future Active Safety Technology towards Zero-Traffic-Accidents (FAST-zero), Society of Automotive Engineers of Japan , 2017, artikel-id 20174621Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cooperative adaptive cruise control (CACC) is a cooperative intelligent transport systems (C-ITS) function, which especially when used in platooning applications, possess many expected benefits including efficient road space utilization and reduced fuel consumption. Cut-in manoeuvres in platoons can potentially reduce those benefits, and are not desired from a safety point of view. Unfortunately, in realistic traffic scenarios, cut-in manoeuvres can be expected, especially from non-connected vehicles. In this paper two different controllers for platooning are explored, aiming at maintaining the safety of the platoon while a vehicle is cutting in from the adjacent lane. A realistic scenario, where a human driver performs the cut-in manoeuvre is used to demonstrate the effectiveness of the controllers. Safety analysis of CACC controllers using time to collision (TTC) under such situation is presented. The analysis using TTC indicate that, although potential risks are always high in CACC applications such as platooning due to the small inter-vehicular distances, dangerous TTC (TTC < 6 seconds) is not frequent. Future research directions are also discussed along with the results.

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  • 168.
    Aramrattana, Maytheewat
    et al.
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). RISE Viktoria, Gothenburg, Sweden.
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    A Novel Risk Indicator for Cut-In Situations2020Ingår i: 2020 IEEE 23rd International Conference on Intelligent Transportation Systems (ITSC), Piscataway, NJ: IEEE, 2020, artikel-id 9294315Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cut-in situations occurs when a vehicle intention- ally changes lane and ends up in front of another vehicle or in-between two vehicles. In such situations, having a method to indicate the collision risk prior to making the cut-in maneuver could potentially reduce the number of sideswipe and rear end collisions caused by the cut-in maneuvers. This paper propose a new risk indicator, namely cut-in risk indicator (CRI), as a way to indicate and potentially foresee collision risks in cut-in situations. As an example use case, we applied CRI on data from a driving simulation experiment involving a manually driven vehicle and an automated platoon in a highway merging situation. We then compared the results with time-to-collision (TTC), and suggest that CRI could correctly indicate collision risks in a more effective way. CRI can be computed on all vehicles involved in the cut-in situations, not only for the vehicle that is cutting in. Making it possible for other vehicles to estimate the collision risk, for example if a cut-in from another vehicle occurs, the surrounding vehicles could be warned and have the possibility to react in order to potentially avoid or mitigate accidents. © 2020 IEEE.

  • 169.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi. RISE Viktoria, Gothenburg, Sweden.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute (VTI), Sweden.
    Nåbo, Arne
    Swedish National Road and Transport Research Institute (VTI), Sweden.
    A Simulation Study on Effects of Platooning Gaps on Drivers of Conventional Vehicles in Highway Merging Situations2022Ingår i: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 23, nr 4, s. 3790-3796Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Platooning refers to a group of vehicles that--enabled by wireless vehicle-to-vehicle (V2V) communication and vehicle automation--drives with short inter-vehicular distances. Before its deployment on public roads, several challenging traffic situations need to be handled. Among the challenges are cut-in situations, where a conventional vehicle--a vehicle that has no automation or V2V communication--changes lane and ends up between vehicles in a platoon. This paper presents results from a simulation study of a scenario, where a conventional vehicle, approaching from an on-ramp, merges into a platoon of five cars on a highway. We created the scenario with four platooning gaps: 15, 22.5, 30, and 42.5 meters. During the study, the conventional vehicle was driven by 37 test persons, who experienced all the platooning gaps using a driving simulator. The participants' opinions towards safety, comfort, and ease of driving between the platoon in each gap setting were also collected through a questionnaire. The results suggest that a 15-meter gap prevents most participants from cutting in, while causing potentially dangerous maneuvers and collisions when cut-in occurs. A platooning gap of at least 30 meters yield positive opinions from the participants, and facilitating more smooth cut-in maneuvers while less collisions were observed.

  • 170.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). RISE Viktoria, Gothenburg, Sweden.
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Simulation of Cut-In by Manually Driven Vehicles in Platooning Scenarios2017Ingår i: 2017 IEEE 20th International Conference on Intelligent Transportation Systems (ITSC), Piscataway, NJ: IEEE, 2017, s. 1-6Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the near future, Cooperative Intelligent Transport System (C-ITS) applications are expected to be deployed. To support this, simulation is often used to design and evaluate the applications during the early development phases. Simulations of C-ITS scenarios often assume a fleet of homogeneous vehicles within the transportation system. In contrast, once C-ITS is deployed, the traffic scenarios will consist of a mixture of connected and non-connected vehicles, which, in addition, can be driven manually or automatically. Such mixed cases are rarely analysed, especially those where manually driven vehicles are involved. Therefore, this paper presents a C-ITS simulation framework, which incorporates a manually driven car through a driving simulator interacting with a traffic simulator, and a communication simulator, which together enable modelling and analysis of C-ITS applications and scenarios. Furthermore, example usages in the scenarios, where a manually driven vehicle cut-in to a platoon of Cooperative Adaptive Cruise Control (CACC) equipped vehicles are presented. © 2017 IEEE.

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  • 171.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR Centrum för tillämpade intelligenta system (IS-lab). Viktoria Swedish ICT, Gothenburg, Sweden.
    Dimensions of Cooperative Driving, ITS and Automation2015Ingår i: 2015 IEEE Intelligent Vehicles Symposium (IV), Piscataway, NJ: IEEE Press, 2015, s. 144-149Konferensbidrag (Refereegranskat)
    Abstract [en]

    Wireless technology supporting vehicle-to-vehicle (V2V), and vehicle-to-infrastructure (V2I) communication, allow vehicles and infrastructures to exchange information, and cooperate. Cooperation among the actors in an intelligent transport system (ITS) can introduce several benefits, for instance, increase safety, comfort, efficiency. Automation has also evolved in vehicle control and active safety functions. Combining cooperation and automation would enable more advanced functions such as automated highway merge and negotiating right-of-way in a cooperative intersection. However, the combination have influences on the structure of the overall transport systems as well as on its behaviour. In order to provide a common understanding of such systems, this paper presents an analysis of cooperative ITS (C-ITS) with regard to dimensions of cooperation. It also presents possible influence on driving behaviour and challenges in deployment and automation of C-ITS.

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  • 172.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    A simulation framework for cooperative intelligent transport systems testing and evaluation2019Ingår i: Transportation Research Part F: Traffic Psychology and Behaviour, ISSN 1369-8478, E-ISSN 1873-5517, Vol. 61, s. 268-280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Connected and automated driving in the context of cooperative intelligent transport systems (C-ITS) is an emerging area in transport systems research. Interaction and cooperation between actors in transport systems are now enabled by the connectivity by means of vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. To ensure the goals of C-ITS, which are safer and more efficient transport systems, testing and evaluation are required before deployment of C-ITS applications. Therefore, this paper presents a simulation framework—consisting of driving-, traffic-, and network-simulators—for testing and evaluation of C-ITS applications. Examples of cooperative adaptive cruise control (CACC) applications are presented, and are used as test cases for the simulation framework as well as to elaborate on potential use cases of it. Challenges from combining the simulators into one framework, and limitations are reported and discussed. Finally, the paper concludes with future development directions, and applications of the simulation framework in testing and evaluation of C-ITS. © 2017 Elsevier Ltd. All rights reserved.

  • 173.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Cooperative Driving Simulation2016Ingår i: Proceedings of the Driving Simulation Conference 2016, 2016, s. 123-132Konferensbidrag (Refereegranskat)
    Abstract [en]

    For a few decades, driving simulators have been supporting research and development of advanced driver assistance systems (ADAS). In the near future, connected vehicles are expected to be deployed. Driving simulators will need to support evaluation of cooperative driving applications within cooperative intelligent transportation systems (C-ITS) scenarios. C-ITS utilize vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication. Simulation of the inter vehicle communication is often not supported in driving simulators. On the other hand, previous efforts have been made to connect network simulators and traffic simulators, to perform C-ITS simulations. Nevertheless, interactions between actors in the system is an essential aspect of C-ITS. Driving simulators can provide the opportunity to study interactions and reactions of human drivers to the system. This paper present simulation of a C-ITS scenario using a combination of driving, network, and traffic simulators. The architecture of the solution and important challenges of the integration are presented. A scenario from Grand Cooperative Driving Challenge (GCDC) 2016 is implemented in the simulator as an example use case. Lastly, potential usages and future developments are discussed.

  • 174.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Nåbo, Arne
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Extended Driving Simulator for Evaluation of Cooperative Intelligent Transport Systems2016Ingår i: SIGSIM-PADS '16: Proceedings of the 2016 annual ACM Conference on SIGSIM Principles of Advanced Discrete Simulation, New York: ACM Digital Library, 2016, s. 255-278Konferensbidrag (Refereegranskat)
    Abstract [en]

    Vehicles in cooperative intelligent transport systems (C-ITS) often need to interact with each other in order to achieve their goals, safe and efficient transport services. Since human drivers are still expected to be involved in C-ITS, driving simulators are appropriate tools for evaluation of the C-ITS functions. However, driving simulators often simplify the interactions or influences from the ego vehicle on the traffic. Moreover, they normally do not support vehicle-to-vehicle and vehicle-to-infrastructure (V2X) communication, which is the main enabler for C-ITS. Therefore, to increase the C-ITS evaluation capability, a solution on how to extend a driving simulator with traffic and network simulators to handle cooperative systems is presented as a result of this paper. Evaluation of the result using two use cases is presented. And, the observed limitations and challenges of the solution are reported and discussed. © 2016 ACM, Inc.

  • 175.
    Aramrattana, Maytheewat
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Patel, Raj Haresh
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi. RISE Viktoria, Gothenburg, Sweden.
    Harri, Jerome
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Jansson, Jonas
    Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Bonnet, Christian
    Communication Systems Department, EURECOM, Sophia-Antipolis, France.
    Evaluating Model Mismatch Impacting CACC Controllers in Mixed Traffic using a Driving Simulator2018Ingår i: 2018 IEEE Intelligent Vehicles Symposium (IV), New York, NY: IEEE, 2018, s. 1867-1872Konferensbidrag (Refereegranskat)
    Abstract [en]

    At early market penetration, automated vehicles will share the road with legacy vehicles. For a safe transportation system, automated vehicle controllers therefore need to estimate the behavior of the legacy vehicles. However, mismatches between the estimated and real human behaviors can lead to inefficient control inputs, and even collisions in the worst case. In this paper, we propose a framework for evaluating the impact of model mismatch by interfacing a controller under test with a driving simulator. As a proof-of-concept, an algorithm based on Model Predictive Control (MPC) is evaluated in a braking scenario. We show how model mismatch between estimated and real human behavior can lead to a decrease in avoided collisions by almost 46%, and an increase in discomfort by almost 91%. Model mismatch is therefore non-negligible and the proposed framework is a unique method to evaluate them. © 2018 IEEE.

  • 176.
    Arashlouzadeh, Amir
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Tillämpad matematik och fysik (MPE-lab).
    Surface Roughness Measurment: Multi-bandFrequency Shift Interferometer based onPolarization Measurement2014Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Optical measurement techniques have been gaining ground for their vast applications in industry and scientific purposes. These techniques are beneficial comparing to the mechanical methods. Non-intrusive, robust, high accuracy and small measurement volume are some of the advantages of the optical metrology. However, these approaches are expensive. Interferometry is one of the most prominent principles of these optical measurements. It employs the study of fringe patterns in order to model surface roughness with a high precision up to nano-meter scale. In this thesis, we mainly focus on the multi-band frequency shifting interferometry based on polarization measurement for 3D surface modeling. The system has advantages such as it is very accurate and there is no need of a phase unwrapping algorithm. Like the conventional phase shifting interferometry, four intensity images are recorded for the four polarization states correspondingly and then the images are processed by MATLAB and the final results are provided. In this technique the need for three cameras and offset correction between the cameras has been revised and optimized by using only one camera. In the first setup trial, a fiber optic switch has been used which does not lead to the desired results and then the switch has been removed and the corresponding images are satisfactory.

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  • 177.
    Araujo, Hugo
    et al.
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Carvalho, Gustavo
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Mohaqeqi, Morteza
    Uppsala University, Uppsala, Sweden.
    Mousavi, Mohammad Reza
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). University of Leicester, Leicester, UK.
    Sampaio, Augusto
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Sound conformance testing for cyber-physical systems: Theory and implementation2017Ingår i: Science of Computer Programming, ISSN 0167-6423, E-ISSN 1872-7964, Vol. 162, s. 35-54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conformance testing is a formal and structured approach to verifying system correctness. We propose a conformance testing algorithm for cyber-physical systems, based on the notion of hybrid conformance by Abbas and Fainekos. We show how the dynamics of system specification and the sampling rate play an essential role in making sound verdicts. We specify and prove error bounds that lead to sound test-suites for a given specification and a given sampling rate. We use reachability analysis to find such bounds and implement the proposed approach using the CORA toolbox in Matlab. We apply the implemented approach on a case study from the automotive domain. © 2017 The Author(s).

  • 178.
    Araujo, Hugo
    et al.
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Carvalho, Gustavo
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Sampaio, Augusto
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Mousavi, Mohammad Reza
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Taromirad, Masoumeh
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    A Process for Sound Conformance Testing of Cyber-Physical Systems2017Ingår i: 2017 IEEE International Conference on Software Testing, Verification and Validation Workshops (ICSTW) / [ed] Randall Bilof, Los Alamitos, CA: IEEE Computer Society, 2017, s. 46-50, artikel-id 7899032Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a process for sound conformance testing of cyber-physical systems, which involves functional but also non-functional aspects. The process starts with a hybrid model of cyber-physical systems in which the correct behavior of the system (at its interface level) is specified. Such a model captures both discrete behavior and evolution of continuous dynamics of the system in time. Since conformance testing inherently involves comparing continuous dynamics, the key parameters of the process are (1) the conformance bounds defining when two signals are sufficiently close to each other, and (2) the permitted error margin in the conformance analysis introduced by sampling of continuous signals. The final parameter of this process is (3) finding (and adjusting) the sampling rate of the dynamic behavior. In the specified process, we provide different alternatives for fixing the error margin of the conformance testing if the sampling rate is fixed, establishing the sampling rate if the error margin is fixed and finding conformance bounds once the sampling rate and the error margin are fixed. © 2017 IEEE.

  • 179.
    Araujo, Hugo
    et al.
    Universidade Federal de Pernambuco, Recife, Brazil.
    Hoenselaar, Ties
    TU Eindhoven, Eindhoven, the Netherlands.
    Mousavi, Mohammad Reza
    University of Leicester, Leicester, England.
    Vinel, Alexey
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Connected Automated Driving: A Model-Based Approach to the Analysis of Basic Awareness Services2020Ingår i: 2020 IEEE 31st Annual International Symposium on Personal, Indoor and Mobile Radio Communications, Piscataway: Institute of Electrical and Electronics Engineers (IEEE), 2020, s. 1-7Konferensbidrag (Refereegranskat)
    Abstract [en]

    Cooperative awareness basic services are key components of several Connected Autonomous Vehicles (CAV) functions. We present a rigorous approach to the analysis of cooperative awareness basic services in a CAV setup. Our approach addresses a major challenge in the traditional analysis techniques of such services, namely, coming up with effective scenarios that can meaningfully cover their various behaviours, exercise the limits of these services and come up with a quantitative means for design-space exploration.Our approach integrates model-based testing and search-based testing to automatically generate scenarios and steer the scenario generation process towards generating inputs that can lead to the most severe hazards. Additionally we define other objectives that maximise the coverage of the model and the diversity of the generated test inputs. The result of applying our technique to the analysis of cooperative awareness services leads to automatically generated hazardous scenarios for parameters that abide by the ETSI ITS-G5 vehicular communications standard. We show that our technique can be used as an effective design-space exploration method and can be used to design adaptive protocols that can mitigate the hazards detected through our initial analysis. © 2020 by IEEE

  • 180.
    Arndt, David
    et al.
    L3 Communications, Inc, Pasadena, CA, United States.
    Bobrow, James E.
    Department of Mechanical and Aerospace Engineering, University of California, Irvine, United States.
    Peters, Steven
    MIT, United States.
    Iagnemma, Karl
    MIT, United States.
    Dubowsky, Steven
    MIT, United States.
    Two-Wheel Self-Balancing of a Four-Wheeled Vehicle2011Ingår i: IEEE Control Systems Magazine, ISSN 1066-033X, Vol. 31, nr 2, s. 29-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cars and trucks are susceptible to accidents due to rollover. In the United States in 2005, 21.1 of a total of 54,718 deaths in vehicle crashes were caused by rollover [1]. Significant research has therefore been devoted to detecting and preventing rollover through active control. Numerous approaches attempt to detect or predict wheel liftoff using onboard sensing and a combination of automatic steering and braking to keep the wheels on the ground [2][4]. © 2006 IEEE.

  • 181.
    Aronsson, John
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Bolmér, Percy
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Hur forensiska verktyg påverkar integriteten på mobiltelefoner2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Användandet av mobiltelefoner och andra mobila enheter är stort i samhället vilket gör att de förekommer allt oftare vid brott och brottsutredningar. Information i dessa enheter måste kunna utvinnas och integriteten på det utvinna materialet säkerställas. Syftet med detta arbete är att undersöker om de forensiska verktygen Xry och Encase påverkar materialet vid utvinning från mobiltelefoner. För att ta reda på detta har en litteraturstudie, en intervju och två experiment utförts. Resultatet från experimenten visade på att det fanns filer vars innehåll ändrades mellan utvinningar. En analys av resultatet visade att det var systemet själv samt processer som skedde innan utvinningen som förändrat innehållet. Slutsatsen blev att verktygen inte påverkar materialet under utvinningsprocessen

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  • 182.
    Arshad, Hamed
    et al.
    University of Oslo, Oslo, Norway.
    Picazo-Sanchez, Pablo
    Högskolan i Halmstad, Akademin för informationsteknologi. Chalmers University of Technology, Gothenburg, Sweden.
    Johansen, Christian
    Norwegian University of Science And Technology, Trondheim, Norway.
    Schneider, Gerardo
    University of Gothenburg, Gothenburg, Sweden.
    Attribute-based encryption with enforceable obligations2023Ingår i: Journal of Cryptographic Engineering, ISSN 2190-8516, Vol. 13, nr 3, s. 343-371Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Attribute-based encryption (ABE) is a cryptographic mechanism that provides fine-grained access control to encrypted data, which can thus be stored in, e.g., public clouds. However, ABE schemes lack the notion of obligations, which is common in attribute-based access control systems such as eXtensible Access Control Markup Language and Usage Control. Obligations are used to define and enforce extra constraints that happen before approving or denying an access request. In this paper, we propose OB-ABE, a system for extending any classical ABE with enforceable obligations. Our system architecture has as core component trusted hardware enclaves, implemented with SGX, used for enforcing obligations. We employ ProVerif to formally model OB-ABE and verify its main property called “enforceable obligations,” i.e., if a message is encrypted along with an obligation, then the message can be decrypted only after enforcing the attached obligation. OB-ABE has two more properties: (i) OB-ABE is a “conservative extension” of the underlying ABE scheme, preserving its security properties; (ii) OB-ABE is “backward compatible” in the sense that any ciphertext produced by an ABE scheme can be decrypted by its extended OB-ABE version, and moreover, a ciphertext produced by an OB-ABE scheme can be decrypted by its underlying ABE scheme provided that the ciphertext does not have obligations attached. We also implement in C using Intel SGX a prototype of an OB-ABE extending the well-known ciphertext-policy ABE. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

  • 183.
    Arvidson, R. E.
    et al.
    Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, United States.
    Ashley, J. W.
    School of Earth and Space Exploration, Mars Space Flight Facility, Arizona State University, Tempe, AZ 85287, United States.
    Bell III, J. F.
    Department of Astronomy, Cornell University, Ithaca, NY 14853, United States.
    Chojnacki, M.
    Planetary Geosciences Institute, Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, United States.
    Cohen, J.
    Honeybee Robotics Spacecraft Mechanisms Corporation, 460 W. 34th St., New York, NY 10001, United States.
    Economou, T. E.
    Laboratory for Astrophysics and Space Research, Enrico Fermi Institute, University of Chicago, Chicago, IL 60637, United States.
    Farrand, W. H.
    Space Science Institute, 4750 Walnut St., Boulder, CO 80301, United States.
    Fergason, R.
    U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, United States.
    Fleischer, I.
    Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, D-55099 Mainz, Germany.
    Geissler, P.
    U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, United States.
    Gellert, R.
    Department of Physics, University of Guelph, Guelph, ON N1G 2W1, Canada.
    Golombek, M. P.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, United States.
    Grotzinger, J. P.
    Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, United States.
    Guinness, E. A.
    Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, United States.
    Haberle, R. M.
    NASA Ames Research Center, Moffett Field, CA 94035, United States.
    Herkenhoff, K. E.
    U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, United States.
    Herman, J. A.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, United States.
    Iagnemma, Karl
    MIT, USA.
    Jolliff, B. L.
    Department of Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, United States.
    Johnson, J. R.
    U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, United States.
    Klingelhöfer, G.
    Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, D-55099 Mainz, Germany.
    Knoll, A. H.
    Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States.
    Knudson, A. T.
    Planetary Science Institute, 1700 East Fort Lowell, Tucson, AZ 85719, United States.
    Li, R.
    Department of Civil and Environmental Engineering and Geodetic Science, Ohio State University, Columbus, OH 43210, United States.
    McLennan, S. M.
    Department of Geosciences, State University of New York at Stony Brook, Stony Brook, NY 11794, United States.
    Mittlefehldt, D. W.
    NASA Johnson Space Center, Houston, TX 77058, United States.
    Morris, R. V.
    NASA Johnson Space Center, Houston, TX 77058, United States.
    Parker, T. J.
    Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, United States.
    Rice, M. S.
    Department of Astronomy, Cornell University, Ithaca, NY 14853, United States.
    Schröder, C.
    Department of Hydrology, University of Bayreuth, Bayreuth, Germany.
    Soderblom, L. A.
    U.S. Geological Survey, 2255 N. Gemini Dr., Flagstaff, AZ 86001, United States.
    Squyres, S. W.
    Department of Astronomy, Cornell University, Ithaca, NY 14853, United States.
    Sullivan, R. J.
    Department of Astronomy, Cornell University, Ithaca, NY 14853, United States.
    Wolff, M. J.
    Space Science Institute, 4750 Walnut St., Boulder, CO 80301, United States.
    Opportunity Mars Rover mission: Overview and selected results from Purgatory ripple to traverses to Endeavour crater2011Ingår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 116, s. E00F15-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Opportunity has been traversing the Meridiani plains since 25 January 2004 (sol 1), acquiring numerous observations of the atmosphere, soils, and rocks. This paper provides an overview of key discoveries between sols 511 and 2300, complementing earlier papers covering results from the initial phases of the mission. Key new results include (1) atmospheric argon measurements that demonstrate the importance of atmospheric transport to and from the winter carbon dioxide polar ice caps; (2) observations showing that aeolian ripples covering the plains were generated by easterly winds during an epoch with enhanced Hadley cell circulation; (3) the discovery and characterization of cobbles and boulders that include iron and stony-iron meteorites and Martian impact ejecta; (4) measurements of wall rock strata within Erebus and Victoria craters that provide compelling evidence of formation by aeolian sand deposition, with local reworking within ephemeral lakes; (5) determination that the stratigraphy exposed in the walls of Victoria and Endurance craters show an enrichment of chlorine and depletion of magnesium and sulfur with increasing depth. This result implies that regional-scale aqueous alteration took place before formation of these craters. Most recently, Opportunity has been traversing toward the ancient Endeavour crater. Orbital data show that clay minerals are exposed on its rim. Hydrated sulfate minerals are exposed in plains rocks adjacent to the rim, unlike the surfaces of plains outcrops observed thus far by Opportunity. With continued mechanical health, Opportunity will reach terrains on and around Endeavour's rim that will be markedly different from anything examined to date. Copyright 2011 by the American Geophysical Union.

  • 184.
    Arvidson, R. E.
    et al.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Bell III, J. F.
    Department of Astronomy, Cornell University, Ithaca, NY, United States.
    Bellutta, P.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Cabrol, N. A.
    NASA Ames Research Center, Moffett Field, CA, United States.
    Catalano, J. G.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Cohen, J.
    Honeybee Robotics Spacecraft Mechanisms Corporation, New York, NY, United States.
    Crumpler, L. S.
    New Mexico Museum of Natural History and Science, Albuquerque, United States.
    Marais, D. J. Des
    NASA Ames Research Center, Moffett Field, CA, United States.
    Estlin, T. A.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Farrand, W. H.
    Space Science Institute, Boulder, CO, United States.
    Gellert, R.
    Department of Physics, University of Guelph, Guelph, ON, Canada.
    Grant, J. A.
    Center for Earth and Planetary Studies, Smithsonian Institution, Washington, DC, United States.
    Greenberger, R. N.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Guinness, E. A.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Herkenhoff, K. E.
    U.S. Geological Survey, Flagstaff, AZ, United States.
    Herman, J. A.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Iagnemma, Karl
    Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, United States.
    Johnson, J. R.
    U.S. Geological Survey, Flagstaff, AZ, United States.
    Klingelhöfer, G.
    Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, Mainz, Germany.
    Li, R.
    Department of Civil and Environmental Engineering and Geodetic Science, Ohio State University, Columbus, OH, United States.
    Lichtenberg, K. A.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Maxwell, S. A.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Ming, D. W.
    NASA Johnson Space Center, Houston, TX, United States.
    Morris, R. V.
    NASA Johnson Space Center, Houston, TX, United States.
    Rice, M. S.
    Department of Astronomy, Cornell University, Ithaca, NY, United States.
    Ruff, S. W.
    School of Earth and Space Exploration, Arizona State University, Tempe, AZ, United States.
    Shaw, A.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Siebach, K. L.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    de Souza, P. A.
    Information and Communication Technologies Centre, CSIRO, Hobart, Australia.
    Stroupe, A. W.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Squyres, S. W.
    Department of Astronomy, Cornell University, Ithaca, NY, United States.
    Sullivan, R. J.
    Department of Astronomy, Cornell University, Ithaca, NY, United States.
    Talley, K. P.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Townsend, J. A.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Wang, A.
    Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, United States.
    Wright, J. R.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Yen, A. S.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States.
    Spirit Mars Rover Mission: Overview and selected results from the northern Home Plate Winter Haven to the side of Scamander crater2010Ingår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 115, nr 9, s. E00F03-Artikel i tidskrift (Refereegranskat)
  • 185.
    Arvidson, R.
    et al.
    Washington University in Saint Louis.
    Fuller, D.
    Jet Propulsion Laboratory, Pasadena, CA.
    Heverly, M.
    Jet Propulsion Laboratory, Pasadena, CA.
    Iagnemma, Karl
    MIT.
    Lin, J.
    Jet Propulsion Laboratory, Pasadena, CA.
    Matthews, J.
    SpaceX, Los Angeles, CA.
    Sletten, R.
    5University of Washington.
    Stein, N.
    Washington University in Saint Louis.
    Mars Science Laboratory Curiosity Rover Terramechanics Initial Results2012Konferensbidrag (Övrigt vetenskapligt)
  • 186.
    Arvidson, R.
    et al.
    Washington University in Saint Louis.
    van Dyke, L.
    Washington University in Saint Louis.
    Bennett, K.
    Washington University in Saint Louis.
    Zhou, F.
    Washington University in Saint Louis.
    Iagnemma, Karl
    MIT.
    Senatore, C.
    MIT.
    Lindemann, R.
    Caltech, Pasadena.
    Trease, B.
    Caltech, Pasadena.
    Maxwell, S.
    Caltech, Pasadena.
    Bellutta, P.
    Caltech, Pasadena.
    Stroupe, A.
    Caltech, Pasadena.
    Hartman, F.
    Caltech, Pasadena.
    Verma, V.
    Caltech, Pasadena.
    Ali, K.
    Caltech, Pasadena.
    Mars Exploration Rover Opportunity Terramechanics Across Ripple Covered Bedrock In Meridiani Planum2011Konferensbidrag (Övrigt vetenskapligt)
  • 187.
    Arvidsson, Christoffer
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Andersson, Jakob
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Virtual Validation of Autonomous Vehicles: Virtualizing an Electric Cabin Scooter2023Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete presenterar en studie om virtualiseringen av en elektrisk kabinscooter. Den virtuella modellen används för att validera genomförbarheten av att omvandla den till ett autonomt fordon. Projektet syftade till att designa, utveckla och testa en virtuell modell av bilen som kan navigera från punkt A till B medan den undviker hinder. Rapporten beskriver metodiken som används i projektet, vilket inkluderar att sätta upp arbetsytan, konstruktion av den virtuella modellen, implementering av ROS2-kontroller och integration av SLAM och Navigation2. Rapporten diskuterar även relaterat arbete, samt teoretisk bakgrund till arbetet. Resultaten visar en framgångsrikt utvecklad fungerande virtuell fordonsmodell, som ger en solid utgångspunkt för framtida arbete.

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  • 188.
    Arvidsson, Moa
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Att använda Azure som IoT plattform2020Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Portabilitet av internet of things lösningar är i dagens samhälle nödvändig. Detta pågrund av den snabba tillväxten av bärbara datorenheter. Allt fler företag väljer att använda molntjänster för lagring och bearbetning av data. Halmstad Kommun håller på att utveckla en kommuntäckande IoT-plattform och använder sig i dagsläget av Nokia IMPACT. Problemet med IMPACT är att den inte har fullt stöd för End-to-end lösningar. Därför undersöker Stadsnätet andra möjligheter för IoT-lösning när det kommer till mjukvara. Microsoft AZURE är en plattform som Halmstad kommun använder för IT lösningar. De övergripande målet med det här projektet är att testa portabiliteten för Microsoft AZUREs IoTlösnignar på IMPACT-plattformen. De metoder som använts har varit att skapa en End-to-end lösning för AZURE och sedan steg för steg testa att överföra den till IMPACT. Slutsatsen av projektet är att portabilitet mellan dessa två plattformar är god, men dock krävs vissa åtgärder vid överföring.

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  • 189.
    Arvidsson, Moa
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Sawirot, Sithichot
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Englund, Cristofer
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Alonso-Fernandez, Fernando
    Högskolan i Halmstad, Akademin för informationsteknologi, Centrum för forskning om tillämpade intelligenta system (CAISR).
    Torstensson, Martin
    RISE Viktoria, Gothenburg, Sweden.
    Duran, Boris
    RISE Viktoria, Gothenburg, Sweden.
    Drone navigation and license place detection for vehicle location in indoor spaces2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    Millions of vehicles are transported every year, tightly parked in vessels or boats. To reduce the risks of associated safety issues like fires, knowing the location of vehicles is essential, since different vehicles may need different mitigation measures, e.g. electric cars. This work is aimed at creating a solution based on a nano-drone that navigates across rows of parked vehicles and detects their license plates. We do so via a wall-following algorithm, and a CNN trained to detect license plates. All computations are done in real-time on the drone, which just sends position and detected images that allow the creation of a 2D map with the position of the plates. Our solution is capable of reading all plates across eight test cases (with several rows of plates, different drone speeds, or low light) by aggregation of measurements across several drone journeys.

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  • 190.
    Ashraf, Nouman
    et al.
    Dublin Institute of Technology, Dublin, Ireland.
    Taqua, Saeed
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Taghvaee, Hamidreza
    University of Nottingham, Nottingham, United Kingdom.
    Abadal, Sergi
    Universitat Politècnica De Catalunya, Barcelona, Spain.
    Vassiliou, Vasos
    University of Cyprus, Nicosia, Cyprus; Smart Systems And Emerging Technologies (rise), Nicosia, Cyprus.
    Liaskos, Christos
    Institute of Computer Science, Heraklion, Greece.
    Pitsillides, Andreas
    University of Cyprus, Nicosia, Cyprus; University Of Johannesburg, Johannesburg, South Africa.
    Lestas, Marios
    Frederick University, Nicosia, Cyprus.
    Intelligent Beam Steering for Wireless Communication Using Programmable Metasurfaces2023Ingår i: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 24, nr 5, s. 4848-4861Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reconfigurable Intelligent Surfaces (RIS) are well established as a promising solution to the blockage problem in millimeter-wave (mm-wave) and terahertz (THz) communications, envisioned to serve demanding networking applications, such as 6G and vehicular. HyperSurfaces (HSF) is a revolutionary enabling technology for RIS, complementing Software Defined Metasurfaces (SDM) with an embedded network of controllers to enhance intelligence and autonomous operation in wireless networks. In this work, we consider feedback-based autonomous reconfiguration of the HSF controller states to establish a reliable communication channel between a transmitter and a receiver via programmable reflection on the HSF when Line-of-sight (LoS) between them is absent. The problem is to regulate the angle of reflection on the metasurface such that the power at the receiver is maximized. Extremum Seeking Control (ESC) is employed with the control signals generated mapped into appropriate metasurface coding signals which are communicated to the controllers via the embedded controller network (CN). This information dissemination process incurs delays which can compromise the stability of the feedback system and are thus accounted for in the performance evaluation. Extensive simulation results demonstrate the effectiveness of the proposed method to maximize the power at the receiver within a reasonable time even when the latter is mobile. The spatiotemporal nature of the traffic for different sampling periods is also characterized. Author

  • 191.
    Aslam, Muhammad Shamrooz
    et al.
    School of Automation, Guangxi University of Science and Technology, Liuzhou, P.R. China.
    Tiwari, Prayag
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Pandey, Hari Mohan
    Data Science and Artificial Intelligence, Department of Information and Computing, Bournemouth University, Bournemouth, United Kingdom.
    Band, Shahab S.
    Future Technology Research Center, College of Future, National Yunlin University of Science and Technology, Douliou, Taiwan, Republic of China.
    Observer–Based Control for a New Stochastic Maximum Power Point tracking for Photovoltaic Systems With Networked Control System2023Ingår i: IEEE transactions on fuzzy systems, ISSN 1063-6706, E-ISSN 1941-0034, Vol. 31, nr 6, s. 1870-1884Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study discusses the new stochastic maximum power point tracking (MPPT) control approach towards the photovoltaic cells (PCs). PC generator is isolated from the grid, resulting in a direct current (DC) microgrid that can provide changing loads. In the course of the nonlinear systems through the time-varying delays, we proposed a Networked Control Systems (NCSs) beneath an event-triggered approach basically in the fuzzy system. In this scenario, we look at how random, variable loads impact the PC generator's stability and efficiency. The basic premise of this article is to load changes and the value matching to a Markov chain. PC generators are complicated nonlinear systems that pose a modeling problem. Transforming this nonlinear PC generator model into the Takagi–Sugeno (T–S) fuzzy model is another option. Takagi–Sugeno (T–S) fuzzy model is presented in a unified framework, for which 1) the fuzzy observer–based on this premise variables can be used for approximately in the infinite states to the present system, 2) the fuzzy observer–based controller can be created using this same premises be the observer, and 3) to reduce the impact of transmission burden, an event-triggered method can be investigated. Simulating in the PC generator model for the realtime climate data obtained in China demonstrates the importance of our method. In addition, by using a new Lyapunov–Krasovskii functional (LKF) for combining to the allowed weighting matrices incorporating mode-dependent integral terms, the developed model can be stochastically stable and achieves the required performances. Based on the T-P transformation, a new depiction of the nonlinear system is derived in two separate steps in which an adequate controller input is guaranteed in the first step and an adequate vertex polytope is ensured in the second step. To present the potential of our proposed method, we simulate it for PC generators. © 2022 IEEE.

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  • 192.
    Aslam, Muhammad Shamrooz
    et al.
    China University of Mining And Technology, Xuzhou, China; Guangxi University of Science and Technology, Liuzhou, China.
    Tiwari, Prayag
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Pandey, Hari Mohan
    Bournemouth University, Bournemouth, United Kingdom.
    Band, Shahab S.
    National Yunlin University of Science and Technology, Douliou, Taiwan.
    Robust stability analysis for class of Takagi-Sugeno (T-S) fuzzy with stochastic process for sustainable hypersonic vehicles2023Ingår i: Information Sciences, ISSN 0020-0255, E-ISSN 1872-6291, Vol. 641, artikel-id 119044Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recently, the rapid development of Unmanned Aerial Vehicles (UAVs) enables ecological conservation, such as low-carbon and “green” transport, which helps environmental sustainability. In order to address control issues in a given region, UAV charging infrastructure is urgently needed. To better achieve this task, an investigation into the T–S fuzzy modeling for Sustainable Hypersonic Vehicles (SHVs) with Markovian jump parameters and H∞ attitude control in three channels was conducted. Initially, the reentry dynamics were transformed into a control–oriented affine nonlinear model. Then, the original T–S local modeling method for SHV was projected by primarily referring to Taylor's expansion and fuzzy linearization methodologies. After the estimation of precision and controller complexity was assumed, the fuzzy model for jump nonlinear systems mainly consisted of two levels: a crisp level and a fuzzy level. The former illustrates the jumps, and the latter a fuzzy level that represents the nonlinearities of the system. Then, a systematic method built in a new coupled Lyapunov function for a stochastic fuzzy controller was used to guarantee the closed–loop system for H∞ gain in the presence of a predefined performance index. Ultimately, numerical simulations were conducted to show how the suggested controller can be successfully applied and functioned in controlling the original attitude dynamics. © 2023 Elsevier Inc.

  • 193.
    Asplund, Martin
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Landin, Robin
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Steering of the second front axle in Volvo trucks2020Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Med några års mellanrum får moderna tunga fordon en ny design och kan frakta mer gods än tidigare. Men att öka mängden gods innebär att öka vikten, vilket leder till mer tryck på ingenjörerna för att designa förbättrade fordonsramar och axlar för att fördela denna last bättre. Nyligen har en andra framaxel lagts till. Denna axel har styrts med en mekanisk länk sedan den infördes, men tack vare de senaste lagändringarna finns nu möjligheten att styra denna axel med ett elektro-hydrauliskt system. Syftet med projektet är just det, att skapa ett elektro-hydrauliskt styrsystem, kan även kallas steer-by-wire (SBW). Genom möten med ingenjörer på Volvo GTT kunde det första utkastet till några koncept uppnås. Koncepten bestod av en CAD-konstruktion av styrningen, kompletterad med en hydraulisk styrning. Genom att återanvända befintliga delar i den nya designen uppnåddes en liknande styrfunktion. Men att ha ett SBW-system som kan kopplas direkt till den nya axeln, det är inte längre begränsat med en anslutning till den första axeln, nu sätter bara fantasin gränserna. Vikten minskas, bränsle- och energiförbrukning minskas, men kanske viktigast av allt. Flexibiliteten i detta system ökar, vilket gör det möjligt att ha oberoende styrning från den första axeln och till och med ändra axelns placering på själva ramen. Ett system som det här kan ha en stor inverkan på miljöeffekterna av lastbilar, eftersom det kan minska antalet fordon på vägen. Tack vare den ökade mängden dom nu kan frakta.

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  • 194.
    Assabie, Yaregal
    et al.
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Bigun, Josef
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Ethiopic Document Image Database for Testing Character Recognition Systems2006Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In this paper we describe the acquisition and content of a large database of Ethiopic documents for testing and evaluating character recognition systems. The Ethiopic Document Image Database (EDIDB) contains documents written in Amharic and Geez languages. The database was built from a variety of documents such as printouts, books, newspapers, and magazines. Documents written in various font types, sizes and styles were included in the database. Degraded and poor quality documents were also included in the database to represent the real life situation. A total of 1,204 pages were scanned at a resolution of 300 dpi and saved as grayscale images of JPEG format. We also describe an evaluation protocol for standardizing the comparison of recognition systems and their results. The database is made available to the research community through http://www.hh.se/staff/josef/.

  • 195.
    Assabie, Yaregal
    et al.
    Department of Computer Science, Addis Ababa University, Ethiopia.
    Bigun, Josef
    Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Laboratoriet för intelligenta system.
    Offline handwritten Amharic word recognition2011Ingår i: Pattern Recognition Letters, ISSN 0167-8655, E-ISSN 1872-7344, Vol. 32, nr 8, s. 1089-1099Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper describes two approaches for Amharic word recognition in unconstrained handwritten text using HMMs. The first approach builds word models from concatenated features of constituent characters and in the second method HMMs of constituent characters are concatenated to form word model. In both cases, the features used for training and recognition are a set of primitive strokes and their spatial relationships. The recognition system does not require segmentation of characters but requires text line detection and extraction of structural features, which is done by making use of direction field tensor. The performance of the recognition system is tested by a dataset of unconstrained handwritten documents collected from various sources, and promising results are obtained. (C) 2011 Elsevier B.V. All rights reserved.

  • 196.
    Assarsson, Fredrik
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Nilsson, Felix
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Utredning av övertoners effekter på transformatorer2019Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete är en utredning om hur en av Halmstad Energi och Miljö Nät ABs transformatorer påverkas av övertoner. Utredningen handlar till största del om hur mycket transformatorns nominella effekt måste skrivas ner. Examensarbetet visar teorin kring både vad som är övertoner, övertoners effekter på transformatorer samt beräkningsmodeller för effektnedskrivning. De metoder som används och jämförs för nedskrivning av transformatoreffekt är faktor K, som beskrivs i SS-EN 50464-3 och K-faktor, som beskrivs i ANSI/IEEE C57.100.

    För att på ett verklighetstroget och ingenjörsmässigt sätt beräkna hur de olika standarderna påverkar transformatorn har tre fall testats.  

    • Övertonernas medelinverkan under en månad, utifrån insamlade mätdata.
    • Övertonernas maximala inverkan under en månad, utifrån insamlade mätdata.
    • Övertonernas inverkan om övertonshalterna ökar i framtiden.

    Resultatet av utredningen visar att transformatorns nominella effekt i fallen där mätdata behandlas bör minskas med ca 6–17% för K-faktor-metoden. För faktor K är de siffrorna ca 2,5–7,5%. Dock visar mätdata från samtliga fallen att belastningsgraden på den testade trans-formatorn är långt under den maximala nedskrivna effekten. Om mängden strömövertoner i framtiden skulle öka är en nedskrivning på 30% av maxeffekten inte orimligt. 

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  • 197.
    Aujla, Gagangeet Singh
    et al.
    Thapar University, Patiala, India.
    Chaudhary, Rajat
    Thapar University, Patiala, India.
    Kumar, Neeraj
    Thapar University, Patiala, India.
    Rodrigues, Joel J. P. C.
    National Institute of Telecommunications (Inatel), Santa Rita do Sapucaí, Brazil; University of Beira Interior, Covilhã, Portugal; ITMO University, St. Petersburg, Russia; University of Fortaleza (Unifor), Fortaleza, Brazil.
    Vinel, Alexey
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Data Offloading in 5G-Enabled Software-Defined Vehicular Networks: A Stackelberg-Game-Based Approach2017Ingår i: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 55, nr 8, s. 100-108Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Data offloading using vehicles is one of the most challenging tasks to perform due to the high mobility of vehicles. There are many solutions available for this purpose, but due to the inefficient management of data along with the control decisions, these solutions are not adequate to provide data offloading by making use of the available networks. Moreover, with the advent of 5G and related technologies, there is a need to cope with high speed and traffic congestion in the existing infrastructure used for data offloading. Hence, to make intelligent decisions for data offloading, an SDN-based scheme is presented in this article. In the proposed scheme, an SDNbased controller is designed that makes decisions for data offloading by using the priority manager and load balancer. Using these two managers in SDN-based controllers, traffic routing is managed efficiently even with an increase in the size of the network. Moreover, a single-leader multi-follower Stackelberg game for network selection is also used for data offloading. The proposed scheme is evaluated with respect to several parameters where its performance was found to be superior in comparison to the existing schemes. © Copyright 2017 IEEE

  • 198.
    Auvoja, Kevin
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Sturesson, Rasmus
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Robotic Process Automation (RPA) i sjukvården:: En studie om effektivisering och dess påverkan för personal och patienter2023Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Dagens digitalisering ställer allt högre krav på verksamheter, då större datamängder behöver hanteras på ett effektivt och säkert sätt. Att applicera digitala verktyg och tekniker inom verksamheter kan stödja effektivare datahantering samtidigt som mänskliga resurser frigörs. Inom hälso- och sjukvården läggs mycket tid på administrativa arbetsuppgifter vilket innebär att det blir mindre tid över till själva kärnverksamheten, som är vård av patienter. Robotic Process Automation (RPA) är en teknik som kan bidra till att minska sjukvårdspersonalens administrativa arbete, där personalen i sin tur kan ha ett större patientfokus. RPA är ett digitalt verktyg som automatiserar repetitiva och regelbaserade verksamhetsprocesser genom att operera i samma gränssnitt som en mänsklig resurs. RPA imiterar hur en användare arbetar i ett digitalt system och kan därefter utföra olika affärsprocesser utan mänsklig inblandning. Det finns både möjligheter och utmaningar när det kommer till RPA inom hälso- och sjukvården. Studiens syfte är att undersöka vilka möjligheter och utmaningar som kan uppstå efter införandet av RPA på olika sjukhus. Uppsatsen kommer anta en kvalitativ ansats, där semistrukturerade intervjuer kommer användas för att samla in empiriskdata från ett antal olika sjukhus. Empirin tillsammans med tidigare forskning på området kommer mynna ut i slutsatser kring vilka möjligheter och utmaningar som finns efter införandet av RPA i sjukvården. Slutligen kommer en tabell presenteras som visar identifierade möjligheter och utmaningar kopplat till de tre organisationsmålsättningarna: effektivitet, kvalitet och kostnader.

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  • 199.
    Awaysheh, Feras M.
    et al.
    University of Tartu, Tartu, Estonia.
    Alawadi, Sadi
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Alzubi, Sawsan
    Independent Researcher, Tartu, Estonia.
    FLIoDT: A Federated Learning Architecture from Privacy by Design to Privacy by Default over IoT2022Ingår i: 2022 Seventh International Conference on Fog and Mobile Edge Computing (FMEC): Paris, France, 12-15 December 2022 / [ed] Saleh I., Ghedira C., Jararweh Y., Benkhelifa E., Boubchir L., Piscataway, N.J.: IEEE, 2022, s. 1-6Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Internet of Things (IoT) realized exponential growth of smart devices with decent capabilities, promising an era of Edge Intelligence. This paradigm creates a timely need to shift many computations closer to the data source at the network's edge. Data privacy is paramount, as security breaches can severely impact such an environment with its vast attack surface. The advent of Federated learning (FL), a privacy-by-design with decentralized machine learning (ML), enables participants to collaboratively train a model without sharing their sensitive data. Nevertheless, privacy implications are a glaring concern and perrier for widening the utilization of FL approaches and their mass adoption over IoT applications. This paper introduces the notion of FL over the Internet of Disconnected Things (FLIoDT), a functionality separation of concerns following the air-gapped networks. FLIoDT provides a practical methodology to mitigate Data threats/attacks in the FL domain. FLIoDT proves a practical architectural approach to mitigate several attacks in an Edge environment. Data dredging and adversarial attacks, like data poisoning, to name some. This study investigates human activity recognition of health monitoring patient data over edge computing to validate FLIoDT. © 2022 IEEE.

  • 200.
    Axelsson, Alexander
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Karlsson, Viktor
    Högskolan i Halmstad, Akademin för informationsteknologi.
    Undersökning om likströmmars påverkan på jordfelsbrytare2020Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna rapport är ett examensarbete skrivet av studenter på Högskolan i Halmstad som läser elektroingenjörsprogrammet med inriktning elkraftteknik. Examensarbetet beskriver en undersökning av jordfelsbrytare, med fokus på jordfelsbrytare av typ A och hur deras beteende ändras vid närvaro av likströmmar. Rapporten inkluderar dessutom bakomliggande fakta om hur jordfelsbrytare fungerar, jordfel och läckströmmar, komponenter som kan ge upphov till likströmmar i en elektrisk krets samt en beskrivning av farorna kopplade till elektricitet. 

    Mätningarna som presenteras är gjorda under så enkla förhållanden som möjligt genom att använda ett testinstrument med jordfelsbrytartest. Likströmmen och växelströmmen som används kopplas och justeras separat för att få så exakta mätvärden som möjligt.

    Testerna resulterar i att jordfelsbrytare inte slutar fungera direkt när likströmmarna blir för stora, utan att mängden jordfelsström som behövs för att få jordfelsbrytaren att slå ifrån istället höjs. En annan slutsats som dras är att mängden likström som behövs för att det här fenomenet skall uppstå verkar vara betydligt högre än de minimala 6mA som industrin använder sig utav vid beskrivning av typ A jordfelsbrytare och ställer frågan om inte den gränsen är ett dåligt utgångsvärde för när typ A slutar fungera.

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