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

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

  • 2.
    Al Hayani, Musab
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Modeling Bus Load on CAN2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The existence of high load and latency in the CAN bus network would indeed lead to a situation where a given message crosses its deadline; this situation would disturb the continuity of the required service as well as activating fault codes due to delay of message delivery, which might lead to system failure.

    The outcome and goal of this thesis is to research and formulate methods to determine and model busload and latencies, by determining parameters such as alpha and breakdown utilization, which are considered as indications to the start of network breakdown when a given message in a dataset start to introduce latency by crossing its deadline which are totally prohibited in critical real time communications.

    The final goal of this master thesis is to develop a TOOL for calculating, modeling, determining and visualizing worst case busload, throughput, networks’ breakdown points and worst case latency in Scania CAN bus networks which is based on the J1939 protocol.

    SCANLA (The developed CAN busload analyzer tool in this thesis) is running as an executable application and uses a Graphical User Interface as a human-computer interface (i.e., a way for humans to interact with the tool) that useswindows,icons and menus and which can be manipulated by a mouse.

  • 3.
    Alam, Ashraful
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Parallelization of the Estimation Algorithm of the 3D Structure Tensor2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis work provides the implementation of 3D structure tensor on a Massively Parallel Processor Array (MPPA), Ambric 2045.

     

    The 3D structure tensor algorithm is often used in image processing applications to compute the optical flow or to detect local 3D structures and their directions. The 3D structure tensor algorithm (3D-STA) consists of three main parts: gradient, tensor and smoothing. This algorithm is computationally expensive due to many multiplications and additions which are required to calculate the gradient (edge), the tensor and to smooth every pixel of the image. This is why this algorithm is very slow to run on a single processor. Therefore, it is important to make it parallel for high performance computation.

     

    This thesis provides two parallel implementations of 3D-STA; namely coarse-grained parallelism and fine-grained parallelism. Ambric has 336 processors. Only 49 processors are used in coarse-grained implementation and 165 processors are used in fine-grained implementation. The performance of the two implementations is measured using a video stream input, consisting of a sequence of images of size 20x256x256. The performance of the coarse-grained parallelism implementation is 25 frames per second (fps) and the one of the fine-grained parallelism implementation is 100 fps. Thus the fine-grained version is four time faster than the coarse-grained one.

     

    Additionally, the results are compared with the result of the Matlab implementation, running on Intel(R) Core 2 duo @2.10 GHz processor and also compared with another parallel optical flow implementation, in terms of speed and efficiency. The coarse-grained implementation is 58 times faster than the Matlab implementation and it achieves approximately half of the performance of the other parallel optical flow implementation. On the other hand, the fine-grained implementation is 230 times faster than the Matlab implementation and more than twice as (100/43) fast as the other parallel optical flow implementation.

     

    These performance results are satisfactory and the results that our parallel implementations can be considered for real-time applications.

     

  • 4.
    Alam, Ashraful
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Ul-Abdin, Zain
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Parallelization of the Estimation Algorithm of the 3D Structure Tensor2012In: 2012 International Conference on Reconfigurable Computing and FPGAs, ReConFig 2012 / [ed] Peter Athanas, René Cumplido & Eduardo de la Torre, Piscataway, N.J.: IEEE Press, 2012, article id 6416771Conference paper (Refereed)
    Abstract [en]

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

  • 5.
    Alendal, Gunnar
    et al.
    NTNU, Gjøvik, Norway.
    Dyrkolbotn, Geir Olav
    NTNU, Gjøvik, Norway & Norwegian Defence Cyber Academy (NDCA), Jørstadmoen, Norway.
    Axelsson, Stefan
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Forensics acquisition – Analysis and circumvention of samsung secure boot enforced common criteria mode2018In: Digital Investigation. The International Journal of Digital Forensics and Incident Response, ISSN 1742-2876, E-ISSN 1873-202X, Vol. 24, no Suppl., p. S60-S67Article in journal (Refereed)
    Abstract [en]

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

  • 6.
    Aramrattana, Maytheewat
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Jansson, Jonas
    The Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research. Viktoria Swedish ICT, Gothenburg, Sweden.
    Dimensions of Cooperative Driving, ITS and Automation2015In: 2015 IEEE Intelligent Vehicles Symposium (IV), Piscataway, NJ: IEEE Press, 2015, p. 144-149Conference paper (Refereed)
    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.

  • 7.
    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
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). University of Leicester, Leicester, UK.
    Sampaio, Augusto
    Universidade Federal de Pernambuco, Recife, PE, Brazil.
    Sound conformance testing for cyber-physical systems: Theory and implementation2017In: Science of Computer Programming, ISSN 0167-6423, E-ISSN 1872-7964, Vol. 162, p. 35-54Article in journal (Refereed)
    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).

  • 8.
    Ayaz, Özgün
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Wireless Low Power Data Acquisition Device: Embedded design and application2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Embedded systems are utilized in various modern-day applications in order to ease routine tasks that are otherwise demanding in manpower; an example of which is data sensing and acquisition. Modern sensor applications usually involve one or more embedded microcomputer systems with inputs from various sensors and a means of connection to transmit the acquitted data to its point of interest. While many sensor and acquisition applications and standards exist for industrial use, the consumer/small business markets for such devices seem to be fairly bleak in comparison. In this project, various data communication standards for transmitting information between sensors and acquisition devices are investigated. Wired, such as RS232, I²C, SPI and 1-Wire, as well as wireless protocols like Wi-Fi and ZigBee were studied. Then, a generic wireless data acquisition platform is designed and realized. The reference implementation connects to a wireless LAN network over Wi-Fi, starts a web server and serves HTML5 web pages and a CSS3 style sheet from SPI flash memory. The sensor data is collected from integrated sensor circuits over an I²C link. Device can run on 3 AA batteries for a combined uptime of at least 3 weeks. Lastly, possible expansion options for the implemented device are discussed and supplemented with real-world examples where possible. Feasible consumer applications for such a platform are then given to conclude.

  • 9.
    Balaji Kamalakkannan, Balaji
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Modelling and Simulation of Vehicle Kinematics and Dynamics2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the rapid growth in the automotive industry, vehicles have become more complex and sophisticated. Vehicle development today, involves integration of both electrical and mechanical systems. Their design and production are typically time and cost critical. To complement and support the process of vehicle development and design, majority of the automotive industry use modelling and simulationfor testing automotive applications, vehicle subsystems or the vehicle behaviour in its entirety.

    For the purpose of traffic simulations, where a large number of vehicles and other elements of the road network are simulated, implementing a highly complex vehicle model would greatly affect the performance of the simulation. The complexity of the vehicle model would entail a higher computation time of the system, making it unsuitable for any real time application. There in lies the trade-off indesigning a model that is both fast and accurate. The majority of the vehicle models that have been designed are either domain specific, highly complex or generalized. Thus, in this thesis, two class specific vehicles’ kinematic models with good accuracy and low computation time are presented.

    Two different modelling paradigms have been adopted to design and test these models. The results, challenges and limitations that pertain to these paradigms are also presented and discussed. The results show the feasibility of the proposed kinematic models.

  • 10.
    Bildtmark, Kim
    et al.
    Halmstad University, School of Information Technology.
    Jädersand, Robin
    Halmstad University, School of Information Technology.
    Security Awareness for Mobility: En studie om företagsmobilitet och de säkerhetsrisker som följer2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 11.
    Binotto, Alécio Pedro Delazari
    et al.
    Informatics Institute, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
    Pignaton de Freitas, Edison
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Informatics Institute, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
    Pereira, Carlos Eduardo
    Electrical Engineering Department, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Towards Dynamic Task Scheduling and Reconfiguration using an Aspect Oriented Approach applied on Real-time concerns of Industrial Systems2009In: Elsevier IFAC Publications / IFAC Proceedings series, ISSN 1474-6670, Vol. 13, no PART 1, p. 1423-1428Article in journal (Refereed)
    Abstract [en]

    High performance computational platforms are required by industries that make use of automatic methods to manage modern machines, which are mostly controlled by high-performance specific hardware with processing capabilities. It usually works together with CPUs, forming a powerful execution platform. On an industrial production line, distinct tasks can be assigned to be processed by different machines depending on certain conditions and production parameters. However, these conditions can change at run-time influenced mainly by machine failure and maintenance, priorities changes, and possible new better task distribution. Therefore, self-adaptive computing is a potential paradigm as it can provide flexibility to explore the machine resources and improve performance on different execution scenarios of the production line. One approach is to explore scheduling and run-time task migration among machines’ hardware towards a balancing of tasks, aiming performance and production gain. This way, the monitoring of time requirements and its crosscutting behaviour play an important role for task (re)allocation decisions. This paper introduces the use of software aspect-oriented paradigms to perform machines’ monitoring and a self-rescheduling strategy of tasks to address nonfunctional timing constraints. As case study, tasks for a production line of aluminium ingots are designed. © 2009 IFAC.

  • 12.
    Borgviken, Jonathan
    et al.
    Halmstad University, School of Information Technology.
    Johansson, Carl
    Halmstad University, School of Information Technology.
    Industrial Wireless IPv6 Sensor device2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 13.
    Bouguerra, Abdelbaki
    et al.
    Örebro University, Sweden.
    Andreasson, Henrik
    Örebro University, Sweden.
    Lilienthal, Achim J.
    Örebro University, Sweden.
    Åstrand, Björn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    An Autonomous Robotic System for Load Transportation2009In: 2009 IEEE CONFERENCE ON EMERGING TECHNOLOGIES & FACTORY AUTOMATION (EFTA 2009), Piscataway, N.J.: IEEE, 2009Conference paper (Refereed)
    Abstract [en]

    This paper presents an overview of an autonomous robotic system for material handling. The system is being developed by extending the functionalities of traditional AGVs to be able to operate reliably and safely in highly dynamic environments. Traditionally, the reliable functioning of AGVs relies on the availability of adequate infrastructure to support navigation. In the target environments of our system, such infrastructure is difficult to setup in an efficient way. Additionally, the location of objects to handle are unknown, which requires runtime object detection and tracking. Another requirement to be fulfilled by the system is the ability to generate trajectories dynamically, which is uncommon in industrial AGV systems.

  • 14.
    Bösch, Bernhard Bösch
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Performance Comparison of Multi Agent Platforms in Wireless Sensor Networks.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The technology for the realization of wireless sensors has been available for a long time, but due to progress  and  development  in  electrical  engineering  such  sensors  can  be  manufactured  cost effectively  and  in  large  numbers  nowadays.  This  availability  and  the  possibility  of  creating cooperating  wireless  networks  which  consist  of  such  sensors  nodes,  has  led  to  a  rapidly  growing popularity  of  a  technology  named  Wireless  Sensor  Networks  (WSN).  Its  disadvantage  is  a  high complexity in the task of programming applications based on WSN, which is a result of its distributed and  embedded  characteristic.  To  overcome  this  shortcoming,  software  agents  have  been  identified as  a  suitable  programming  paradigm.  The  agent  based  approach  commonly  uses  a  middleware  for the execution of the software agent. This thesis is meant to compare such agent middleware in their performance in the WSN domain. Therefore two prototypes of applications based on different agent models are implemented for a given set of middleware. After the implementation measurements are extracted  in  various  experiments,  which  give  information  about  the  runtime  performance  of  every middleware in the test set.  In the following analysis it is examined whether each middleware under test  is  suited  for  the  implemented  applications  in  WSN.  Thereupon,  the  results  are  discussed  and compared with the author’s expectations. Finally a short outlook of further possible development and improvements is presented.

  • 15.
    Charismas, Angelos
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Investigation of UWB radar for human monitoring2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ultra Wide Band ( UWB ) radar technology shows great promise for non-contact remotemonitoring of vital signs such as respiration and heart rate. Previous studies show us theusefulness of the UWB-based radar for breathing and heart rate estimation. The obstaclepenetration capabilities of UWB radar make it appropriate for applications such as humanmonitoring, detection of people and parameters of their motion inside buildings and remotediagnosis of a person’s emotional state. The use of UWB radars for vital signs monitoringpresent some challenges:• Small torso movement during the measurement may compromise results.• Respiratory signal may overshadow the heartbeat rate.• Bio-signals are not stationary.• UWB utilizes very low-low power signals that are easily overpowered by noise.Knowing these problems this thesis investigates signal processing techniques in order to overcome these challenges and detect heart rate. In particular, this thesis investigates a new type ofUWB radar which has not be considered in previous publications. The proposed methods istested under several different experimental conditions and several different subjects. Resultsindicate that this type of UWB radar can be successfully used for breathing and heart ratedetection.

  • 16.
    Danqing, Ni
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Zao, Sun
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Junwei, Chen
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    On Time Discrete Simulation of cooperative Vehicle's Kinematic Behaviour2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The vehicle plays an important role in peoples life in modern times. The vehi- cle's behaviour is a complex and detailed subject, which requiring the knowledge of mathematics and physics. Meanwhile, the vehicles' behaviour is aected by a lot of dierent conditions, such as the driver and the environment. For the purpose of trac safety, simulation is required to analyze the vehicles' behaviour. Vari- eties of behaviour models, based on dierent levels (Macroscopic, Mesoscopic and Microscopic) have been presented. Vehicles are able to interact with each other through the Vehicular Ad Hoc Network (VANET). It is worthwhile to simulate how the behaviour is aected by an exchange of kinematic data. This thesis presents a new simulator, which is designed at microscopic level, based on the graph theory. Not only dierent vehicles' behaviour, but also coop- eration between vehicles can be implemented in the simulator. A new model of collision avoidance is created, incorporating the concept of kinematics and human emulation. The car-following model is also performed for the formation of trac

    ow. Overall, the modeling in the simulator is simplied by ignoring the network disturbances. The data collected from the results of the simulation is used to display a scenario as visualization of a vehicles behaviour.

  • 17.
    de Freitas, Edison Pignaton
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Allgayer, Rodrigo S.
    PPGEE, UFRGS, Brazil.
    Wehrmeister, Marco A.
    PPGC, UFRGS, Brazil.
    Pereira, Carlos E.
    PPGEE, UFRGS, Brazil.
    Larsson, Tony
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Supporting platform for heterogeneous sensor network operation based on unmanned vehicles systems and wireless sensor nodes2009In: 2009 IEEE Intelligent Vehicles Symposium, Volumes 1 and 2 / [ed] Institute of Electrical and Electronics, New York: IEEE Press, 2009, p. 786-791Conference paper (Refereed)
    Abstract [en]

    Advances in vehicle intelligence technology is enabling the development of systems composed of unmanned vehicles, which are able to interact with devices spread on the environment in order to take decisions related to their movements. Sensor networks represent an area that can profit a lot of this new possibilities, as autonomous vehicles can be used to carry sensor devices, which interacting with static sensor nodes can enhance the results provided by the overall system. However, some problems arise in applications' development in such systems due to the network nodes heterogeneity, and also the dynamicity of the environment in which they are deployed, which changes constantly. Thus, new platform solutions are necessary to handle the heterogeneous nodes capabilities in order to facilitate coordination and integration among them. This paper proposes a supporting infrastructure to address these problems composed of an adaptive middleware and a customizable sensor node platform. The goal is to support cooperation in heterogeneous sensor networks, which are composed by static and mobile nodes with different capabilities. The middleware adapts itself in order to manage the very distinct computing resources of the nodes, and also changes in the environment and in the application demands. The customizable sensor node platform allows optimizations in hw/sw modules to meet specific application requirements, allowing the creation of low-end and resource rich nodes that work in an integrated network. In order to illustrate the proposed approach, a system for military surveillance applications is presented as case study.

  • 18.
    de Freitas, Edison Pignaton
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Binotto, Alécio Pedro Delazari
    Fraunhofer IGD / TU Darmstadt, Germany.
    Pereira, Carlos Eduardo
    PPGC UFRGS, Brazil.
    Stork, Andre
    Fraunhofer IGD / TU Darmstadt, Germany.
    Larsson, Tony
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Dynamic activity and task allocation supporting uav teams in surveillance systems2009In: Proceedings of the International Multiconference on Computer Science and Information Technology, 2009. IMCSIT '09, Piscataway, N.J.: IEEE Press, 2009, p. 51-58Conference paper (Refereed)
    Abstract [en]

    The use of Unmanned Aerial Vehicles is increasing in the field of area patrolling and surveil- lance. A great issue that emerge in designing such systems is the target workload distribution over a fleet of UAVs, which generally have different capabilities of sensing and computing power. Targets should be assigned to the most suitable UAVs in order to efficiently perform the end-user initiated missions. To perform these missions, the UAVs require powerful high-performance platforms to deal with many dif- ferent algorithms that make use of massive calculations. The use of COTS hardware (e.g., GPU) presents an interesting low-cost alternative to compose the required platform. However, in order to efficiently use these heterogeneous platforms in a dynamic scenario, such as in surveillance systems, runtime reconfigu- ration strategies must be provided. This paper presents a dynamic approach to distribute the handling of targets among the UAVs and a heuristic method to address the efficient use of the heterogeneous hard- ware that equips these UAVs, with the goal to meet also mission timing requirements. Preliminary simu- lation results of the proposed heuristics are also provided.

  • 19.
    de Freitas, Edison Pignaton
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Institute of Informatics, Federal University of Rio Grande do Sul, Brazil.
    Bösch, Bernhard
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Allgayer, Rodrigo
    Electrical Engineering Department, Universidade Federal do Rio Grande do Sul, Brazil.
    Steinfeld, Leonardo
    Electrical Engineering Institute, Universidad de la República, Uruguay.
    Wagner, Flávio
    Institute of Informatics, Federal University of Rio Grande do Sul, Brazil.
    Carro, Luigi
    Institute of Informatics, Federal University of Rio Grande do Sul, Brazil.
    Pereira, Carlos
    Institute of Informatics, Federal University of Rio Grande do Sul, Brazil; Electrical Engineering Department, Universidade Federal do Rio Grande do Sul, Brazil.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Mobile Agents Model and Performance Analysis of a Wireless Sensor Network Target Tracking Application2011In: Smart spaces and next generation wired/wireless networking: 11th International Conference, NEW2AN 2011 and 4th Conference on Smart Spaces, RuSMART 2011, St. Petersburg, Russia, August 22 -25, 2011 ; proceedings / [ed] Sergey Balandin, Heidelberg: Springer Berlin/Heidelberg, 2011, Vol. 6869, p. 274-286Conference paper (Refereed)
    Abstract [en]

    Advances on wireless communication and sensor systems enabled the growing usage of Wireless Sensor Networks. This kind of network is being used to support a number of new emerging applications, thus the importance in studying the efficiency of new approaches to program them. This paper proposes a performance study of an application using high-level mobile agent model for Wireless Sensor Networks. The analysis is based on a mobile object tracking system, a classical WSN application. It is assumed that the sensor nodes are static, while the developed software is implemented as mobile agents by using the AFME framework. The presented project follows a Model-Driven Development (MDD) methodology using UML (Unified Modeling Language) models. Metrics related to dynamic features of the implemented solution are extracted from the deployed application, allowing a design space exploration in terms of metrics such as performance, memory and energy consumption. © Springer-Verlag Berlin Heidelberg 2011.

  • 20.
    Emanuelsson, Herman
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Sjunnesson, Emil
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Fjärrstyrt kamerafäste: HE Remote2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At times when it is not suited to stand by a video camera can be resolved with a remote controlled camera mount. Examples of occasions is due to lack of space at a concert, a solemn ceremony in which someone must stand awkwardly  to to get good image, out in nature where animals shall be filmed without being frightened away or when you have staff shortages, a tight budget and need to control multiple cameras simultaneously. The systems that are available in the amateur market today have different functionality and is not fitting for the above problem or have very limited range and cannot connect to a mobile application.

    This project aims to develop a cost-effective and customized solution for the above problem by developing a remote-controlled camera mount in semi-professional segment where you through a controller and at a later stage with a mobile application controls the camera angle and rotation also called tilt and pan.

    The differences between this and existing solutions are that by using Bluetooth technology can control both the controller and later on also with a mobile application, the reason why it must be able to control both is that it is not always allowed to use cell phones in all environments where you want to film and therefore have a wider range of applications for camera mounting.

  • 21.
    Ericsson, Andreas
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Ericsson, Jonas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Fjärrstyrning av värmepump2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att fjärrstyra sin värmepump gör det möjligt att styra inomhusklimatet även då man inte är hemma. Detta passar mycket bra i exempelvis fritidshus då man enkelt kan höja temperaturen innan man skall dit och därmed kan njuta av ett behagligt inomhusklimat direkt.

    Med dagens fjärrstyrning av Daikins värmepumpar finns två problem. Systemet använder GSM-nätet och användaren måste kunna de olika SMS-koderna utantill. Fjärrstyrning används oftast i fritidshus på landsbygden och 3G-nätet har idag bättre täckning än GSM-nätet på många av dessa platser.

    Målet med examensarbetet är att ta fram ett system som åtgärdar dessa problem.

    Vi börjar med att ta fram en funktionsmodell att utgå från. Går vidare med val av hårdvara för modulen, och därefter vidare till mjukvaruutveckling.

    Resultatet av detta examensarbete är ett system för fjärrstyrning av Daikins värmepumpar som använder 3G-nätet och enkelt kan styras via en androidapplikation.

  • 22.
    Ernst, Robert
    et al.
    Halmstad University, School of Information Technology.
    Nilsson, Emil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Viberg, Per-Arne
    Swedish Adrenaline AB, Halmstad, Sweden..
    60GHz Vital Sign Radar using 3D-printed Lens2016In: 2016 IEEE SENSORS, Piscataway: IEEE, 2016, article id 7808774Conference paper (Refereed)
    Abstract [en]

    There is an increased interest in contact-less vital sign monitoring methods as they offer higher flexibility to the individual being observed. Recent industrial development enabled radar functionality to be packed in single-chip solutions, decreasing application complexity and speeding up designs. Within this paper, a vital sign radar has been developed utilizing a recently released 60GHz frequency modulated continuous wave single-chip radar in combination with 3D-printed quasi-optics. The electronics development has been focused on compactness and high system integration using a low cost design process. The final experiments prove that the radar is capable of tracking human respiration rate and heartbeat at the same time from a distance of 1m.

  • 23.
    Essayas, Gebrewahid
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Yang, Mingkun
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Cedersjö, Gustav
    Department of Computer Science, Lund University, Lund, Sweden.
    Ul-Abdin, Zain
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Gaspes, Veronica
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Janneck, Jörn W.
    Department of Computer Science, Lund University, Lund, Sweden.
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Realizing Efficient Execution of Dataflow Actors on Manycores2014In: Proceedings: 2014 International Conference on Embedded and Ubiquitous Computing: EUC 2014: August 2014, Milano, Italy / [ed] Randall Bilof, Los Alamitos, CA: IEEE Computer Society, 2014, p. 321-328, article id 6962305Conference paper (Refereed)
    Abstract [en]

    Embedded DSP computing is currently shifting towards manycore architectures in order to cope with the ever growing computational demands. Actor based dataflow languages are being considered as a programming model. In this paper we present a code generator for CAL, one such dataflow language. We propose to use a compilation tool with two intermediate representations. We start from a machine model of the actors that provides an ordering for testing of conditions and firing of actions. We then generate an Action Execution Intermediate Representation that is closer to a sequential imperative language like C and Java. We describe our two intermediate representations and show the feasibility and portability of our approach by compiling a CAL implementation of the Two-Dimensional Inverse Discrete Cosine Transform on a general purpose processor, on the Epiphany manycore architecture and on the Ambric massively parallel processor array. © 2014 IEEE.

  • 24.
    Ganjalizadeh, Milad
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Reliability for Hard Real-time Communication in Packet-switched Networks2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nowadays, different companies use Ethernet for different industrial applications. Industrial Ethernet has some specific requirements due to its specific applications and environmental conditions which is the reason that makes it different than corporate LANs. Real-time guarantees, which require precise synchronization between all communication devices, as well as reliability are the keys in performance evaluation of different methods [1].  High bandwidth, high availability, reduced cost, support for open infrastructure as well as deterministic architecture make packet-switched networks suitable for a variety of different industrial distributed hard real-time applications. Although research on guaranteeing timing requirements in packet-switched networks has been done, communication reliability is still an open problem for hard real-time applications.

    In this thesis report, a framework for enhancing the reliability in multihop packet-switched networks is presented. Moreover, a novel admission control mechanism using a real-time analysis is suggested to provide deadline guarantees for hard real-time traffic. A generic and flexible simulator has been implemented for the purpose of this research study to measure different defined performance metrics. This simulator can also be used for future research due to its flexibility. The performance evaluation of the proposed solution shows a possible enhancement of the message error rate by several orders of magnitude, while the decrease in network utilization stays at a reasonable level.

  • 25.
    Gebrewahid, Essayas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Compiling Concurrent Programs for Manycores2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The arrival of manycore systems enforces new approaches for developing applications in order to exploit the available hardware resources. Developing applications for manycores requires programmers to partition the application into subtasks, consider the dependence between the subtasks, understand the underlying hardware and select an appropriate programming model. This is complex, time-consuming and prone to error.

    In this thesis, we identify and implement abstraction layers in compilation tools to decrease the burden of the programmer, increase programming productivity and program portability for manycores and to analyze their impact on performance and efficiency. We present compilation frameworks for two concurrent programming languages, occam-pi and CAL Actor Language, and demonstrate the applicability of the approach with application case-studies targeting these different manycore architectures: STHorm, Epiphany and Ambric.

    For occam-pi, we have extended the Tock compiler and added a backend for STHorm. We evaluate the approach using a fault tolerance model for a four stage 1D-DCT algorithm implemented by using occam-pi’s constructs for dynamic reconfiguration, and the FAST corner detection algorithm which demonstrates the suitability of occam-pi and the compilation framework for data-intensive applications. We also present a new CAL compilation framework which has a front end, two intermediate representations and three backends: for a uniprocessor, Epiphany, and Ambric. We show the feasibility of our approach by compiling a CAL implementation of the 2D-IDCT for the three backends. We also present an evaluation and optimization of code generation for Epiphany by comparing the code generated from CAL with a hand-written C code implementation of 2D-IDCT.

  • 26.
    Gebrewahid, Essayas
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Tools to Compile Dataflow Programs for Manycores2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The arrival of manycore systems enforces new approaches for developing applications in order to exploit the available hardware resources. Developing applications for manycores requires programmers to partition the application into subtasks, consider the dependence between the subtasks, understand the underlying hardware and select an appropriate programming model. This is complex, time-consuming and prone to error. In this thesis, we identify and implement abstraction layers in compilation tools to decrease the burden of the programmer, increase program portability and scalability, and increase retargetability of the compilation framework. We present compilation frameworks for two concurrent programming languages, occam-pi and CAL Actor Language, and demonstrate the applicability of the approach with application case-studies targeting these different manycore architectures: STHorm, Epiphany, Ambric, EIT, and ePUMA. For occam-pi, we have extended the Tock compiler and added a backend for STHorm. We evaluate the approach using a fault tolerance model for a four stage 1D-DCT algorithm implemented by using occam-pi's constructs for dynamic reconguration, and the FAST corner detection algorithm which demonstrates the suitability of occam-pi and the compilation framework for data-intensive applications. For CAL, we have developed a new compilation framework, namely Cal2Many. The Cal2Many framework has a front end, two intermediate representations and four backends: for a uniprocessor, Epiphany, Ambric, and a backend for SIMD based architectures. Also, we have identied and implemented of CAL actor fusion and fission methodologies for efficient mapping CAL applications. We have used QRD, FAST corner detection, 2D-IDCT, and MPEG applications to evaluate our compilation process and to analyze the limitations of the hardware.

  • 27.
    Gebrewahid, Essayas
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ali Arslan, Mehmet
    Lund University, Lund, Sweden.
    Karlsson, Andreas
    Linköping University, Linköping, Sweden.
    Ul-Abdin, Zain
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Support for Data Parallelism in the CAL Actor Language2016In: WPMVP '16: Proceedings of the 3rd Workshop on Programming Models for SIMD/Vector Processing / [ed] Jan Eitzinger, Joel Falcou, Illie Gabriel Tanase & James Brodman, New York, NY: ACM Press, 2016Conference paper (Refereed)
    Abstract [en]

    With the arrival of heterogeneous manycores comprising various features to support task, data and instruction-level parallelism, developing applications that take full advantage of the hardware parallel features has become a major challenge. In this paper, we present an extension to our CAL compilation framework (CAL2Many) that supports data parallelism in the CAL Actor Language. Our compilation framework makes it possible to program architectures with SIMD support using high-level language and provides efficient code generation. We support general SIMD instructions but the code generation backend is currently implemented for two custom architectures, namely ePUMA and EIT. Our experiments were carried out for two custom SIMD processor architectures using two applications.

    The experiment shows the possibility of achieving performance comparable to hand-written machine code with much less programming effort.

  • 28.
    Gebrewahid, Essayas
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ul-Abdin, Zain
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Actor Fission Transformations for Executing Dataflow Programs on Manycores2017In: 2017 Forum on Specification and Design Languages (FDL), 2017Conference paper (Other academic)
    Abstract [en]

    Manycore architectures are dominating the development of advanced embedded computing due to the computational and power demand of high performance applications. This has introduced an additional complexity with regard to the efficient exploitation of the underlying hardware and the development of efficient parallel implementations. To tackle this we model applications using a dataflow programming language, perform high-level transformations of dataflow actors, and generate native code by using our compilation framework.This paper presents the actor fission transformations of our Cal2Many compilation framework. The transformations have facilitated the mapping of big dataflow actors on memory restricted embedded manycores, increased the utilization of the hardware, and enabled support for task and data-level parallelism. We have applied the actor transformations to two blocks of MPEG-4 decoder and executed it on the Epiphany manycore architecture. The result shows the practicality and feasibility of our approach.

  • 29.
    Gebrewahid, Essayas
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ul-Abdin, Zain
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Gaspes, Veronica
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Cal2Many: A Framework to Compile Dataflow Programs for Manycores2017Manuscript (preprint) (Other academic)
    Abstract [en]

    The arrival of manycore platforms has imposed programming challenges for mainstream embedded system developers. In this paper, we discuss the significance of actor-oriented dataflow languages and present our compilation framework for CAL Actor Language that leads to increased portability and retargetability. We demonstrate the applicability of our approach with streaming applications targeting the Epiphany many-core architecture. We have performed an in-depth analysis of MPEG-4 SP implemented on Epiphany using our framework and studied the effects of actor composition. We have identified hardware aspects such as increased off-chip memory bandwidth and larger local memories that could result in further performance improvements.

  • 30.
    Gebrewahid, Essayas
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ul-Abdin, Zain
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Svensson, Bertil
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Mapping Occam-pi programs to a Manycore Architecture2011Conference paper (Refereed)
    Abstract [en]

    Efficient utilization of available resources is a key concept in embedded systems. This paper is focused on providing the support for managing dynamic reconfiguration of computing resources in the programming model. We present an approach to map occam-pi programs to a manycore architecture, Platform 2012 (P2012). We describe the techniques used to translate the salient features of the occam-pi language to the native programing model of the P2012 architecture. We present the initial results from a case study of matrix multiplication. Our results show the simplicity of occam-pi program by 6 times reduction in lines-of-code.

  • 31.
    Gebrewahid, Essayas
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Ul-Abdin, Zain
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Svensson, Bertil
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Gaspes, Veronica
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jego, Bruno
    ST-Microlectronics, Grenoble, France.
    Lavigueur, Bruno
    ST-Microlectronics, Grenoble, France.
    Robart, Mathieu
    ST-Microlectronics, Bristol, United Kingdom.
    Programming Real-time Image Processing for Manycores in a High-level Language2013In: Advanced Parallel Processing Technology / [ed] Wu, Chenggang and Cohen, Albert, Berlin Heidelberg: Springer Berlin/Heidelberg, 2013, p. 381-395Conference paper (Refereed)
    Abstract [en]

    Manycore architectures are gaining attention as a means to meet the performance and power demands of high-performance embedded systems. However, their widespread adoption is sometimes constrained by the need formastering proprietary programming languages that are low-level and hinder portability. We propose the use of the concurrent programming language occam-pi as a high-level language for programming an emerging class of manycore architectures. We show how to map occam-pi programs to the manycore architecture Platform 2012 (P2012). We describe the techniques used to translate the salient features of the language to the native programming model of the P2012. We present the results from a case study on a representative algorithm in the domain of real-time image processing: a complex algorithm for corner detectioncalled Features from Accelerated Segment Test (FAST). Our results show that the occam-pi program is much shorter, is easier to adapt and has a competitive performance when compared to versions programmed in the native programming model of P2012 and in OpenCL.

  • 32.
    Griesebner, Klaus
    Halmstad University, School of Information Technology.
    Model-based Controller Development2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Model-based design is a powerful design technique for embedded system development. The technique enables virtual prototyping to develop and debug controllers before touching real hardware. There are many tools available covering the distinct steps of the design cycle including modeling, simulation, and implementation. Unfortunately, none of them covers all three steps. This thesis proposes a formalism coupling the model and the implementation of a controller for equation-based simulation tools. The resulting formalism translates defined controller models to platform specific code using a defined set of syntax. A case study of a line-following robot has been developed to illustrate the feasibility of the approach. The prototype has been tested and evaluated using a sequence of test scenarios of increasing difficulty. The final experiments suggest that the behaviors of both modeled and generated controllers are similar. The thesis concludes that the approach of model-implementation coupling of controllers in the simplest form is feasible for equation-based tools. This allows it to conduct the whole model-based design cycle within a single environment.

  • 33.
    Grip, Andreas
    Halmstad University, School of Information Technology.
    Kraftmätning på cykelpedal2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report will describe the development of a subsystem for force measurement on bicycle pedals. The force is going to be used as a control parameter in a motor controller to control an electric motor on an electric bicycle. The report focuses on force measurement and will not process any control system. There has also been a survey of alternative power supplies to the circuit boards to be used in this project. Energy Harvesting has been investigated as an alternative source. The aim of the project is to measure the force applied on the pedal in a good way for use in a control system.This work resulted in that the force applied on the pedals was measured on the crank arms. The force was being measured by strain gauge sensors in a test rig designed in this project. The force signal can be used in the intended control system. This report has explained when, during a pedal stroke, the force should be measured. Processing of the signal will be done furthermore in the motor controller to fit the requirements set by the control system.

  • 34.
    Hertz, Erik
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES). Lund University, Lund, Sweden.
    Methodologies for Approximation of Unary Functions and Their Implementation in Hardware2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Applications in computer graphics, digital signal processing, communication systems, robotics, astrophysics, fluid physics and many other areas have evolved to become very computation intensive. Algorithms are becoming increasingly complex and require higher accuracy in the computations. In addition, software solutions for these applications are in many cases not sufficient in terms of performance. A hardware implementation is therefore needed. A recurring bottleneck in the algorithms is the performance of the approximations of unary functions, such as trigonometric functions, logarithms and the square root, as well as binary functions such as division. The challenge is therefore to develop a methodology for the implementation of approximations of unary functions in hardware that can cope with the growing requirements. The methodology is required to result in fast execution time, low complexity basic operations that are simple to implement in hardware, and – sincemany applications are battery powered – low power consumption. To ensure appropriate performance of the entire computation in which the approximation is a part, the characteristics and distribution of the approximation error are also things that must be possible to manage. The new approximation methodologies presented in this thesis are of the type that aims to reduce the sizes of the look-up tables by the use of auxiliary functions. They are founded on a synthesis of parabolic functions by multiplication – instead of addition, which is the most common. Three approximation methodologies have been developed; the two last being further developments of the first. For some functions, such as roots, inverse and inverse roots, a straightforward solution with an approximation is not manageable. Since these functions are frequent in many computation intensive algorithms, it is necessary to find very efficient implementations of these functions. New methods for this are also presented in this thesis. They are all founded on working in a floating-point format, and, for the roots functions, a change of number base is also used. The transformations not only enable simpler solutions but also increased accuracy, since the approximation algorithm is performed on a mantissa of limited range. Tools for error analysis have been developed as well. The characteristics and distribution of the approximation error in the new methodologies are presented and compared with existing state-of-the-art methods such as CORDIC. The verification and evaluation of the solutions have to a large extent been made as comparative ASIC implementations with other approximation methods, separately or embedded in algorithms. As an example, an implementation of the logarithm made using the third methodology developed, Harmonized Parabolic Synthesis (HPS), is compared with an implementation using the CORDIC algorithm. Both implementations are designed to provide 15-bit resolution. The design implemented using HPS performs 12 times better than the CORDIC implementation in terms of throughput. In terms of energy consumption, the new methodology consumes 96% less. The chip area is 60% smaller than for the CORDIC algorithm. In summary, the new approximation methodologies presented are found to well meet the demanding requirements that exist in this area.

  • 35.
    Hertz, Erik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Lai, Jingou
    Lund University, Lund, Sweden.
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Nilsson, Peter
    Lund University, Lund, Sweden.
    The harmonized parabolic synthesis methodology for function generation in hardwareManuscript (preprint) (Other academic)
    Abstract [en]

    The Harmonized Parabolic Synthesis methodology is a further development of the Parabolic Synthesis methodology for approximation of unary functions such as trigonometric functions, logarithms and the square root, as well as binary functions such as division, in hardware.These functions are extensively used in computer graphics, digital signal processing, communication systems, robotics, astrophysics, fluid physics and many other application areas. For these high-speed applications, software solutions are in many cases not sufficient and a hardware implementation is therefore needed. The Harmonized Parabolic Synthesis methodology has two outstanding advantages: it is parallel, thus reducing the execution time, and it is based on low 2complexity operations, thus is simple to implement in hardware. A notable difference in the Harmonized Parabolic Synthesis methodology compared to many other approximation methodologies is that it is a multiplicative and not an additive methodology. Without harming the favorable distribution of the approximation error presented in earlier described Parabolic Synthesis methodologies it is possible to significantly enhances the performance of the Harmonized Parabolic Synthesis methodology, in terms of reducing chip area, computation delay and power consumption. Furthermore it increases the possibility to tailor the characteristics of the error, which improves the conditions for subsequent calculations. It also extends the set of unary functions that approximations can be performed upon since the possibilities to elaborate with the characteristics and distribution of the error increases. To evaluate the proposed methodology, the fractional part of the logarithm has been implemented and its performance is compared to the Parabolic Synthesis methodology. The comparison is made with 15-bit resolution. The design implemented using the Harmonized Parabolic Synthesis methodology performs 3x better than the Parabolic Synthesis implementation in terms of throughput. In terms of energy consumption, the new methodology consumes 90% less. The chip area is 70% smaller than for the Parabolic Synthesis methodology. In summary, the new technology presented in this paper further increases the advantages of Parabolic Synthesis.

  • 36.
    Hertz, Erik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Lai, Jingou
    Lund University, Lund, Sweden.
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Nilsson, Peter
    Lund University, Lund, Sweden.
    The Harmonized Parabolic Synthesis Methodology for Hardware Efficient Function Generation with Full Error Control2017In: Journal of Signal Processing Systems, ISSN 1939-8018, E-ISSN 1939-8115Article in journal (Refereed)
    Abstract [en]

    The Harmonized Parabolic Synthesis methodology is a further development of the Parabolic Synthesis methodology for approximation of unary functions such as trigonometric functions, logarithms and the square root with moderate accuracy for ASIC implementation. These functions are extensively used in computer graphics, communication systems and many other application areas. For these high-speed applications, software solutions are in many cases not sufficient and a hardware implementation is therefore needed. The Harmonized Parabolic Synthesis methodology has two outstanding advantages: it is parallel, thus reducing the execution time, and it is based on low complexity operations, thus is simple to implement in hardware. A difference compared to other approximation methodologies is that it is a multiplicative and not additive, methodology. Compared to the Parabolic Synthesis methodologies it is possible to significantly enhance the performance in terms of reducing chip area, computation delay and power consumption. Furthermore it increases the possibility to tailor the characteristics of the error, improving conditions for subsequent calculations and the performance in design terms. To evaluate the proposed methodology, the fractional part of the logarithm has been implemented and its performance is compared to the Parabolic Synthesis methodology. The comparison is made with 15-bit resolution. The design implemented using the proposed methodology performs 3x better than the Parabolic Synthesis implementation in terms of throughput. In terms of energy consumption, the new methodology consumes 90% less. The chip area is 70% smaller than for the Parabolic Synthesis methodology. In summary, the new technology further increases the advantages of Parabolic Synthesis. © 2017 The Author(s)

  • 37.
    Hertz, Erik
    et al.
    Department of Electrical and Information Technology Lund University, Lund, Sweden.
    Nilsson, Peter
    Department of Electrical and Information Technology Lund University, Lund, Sweden.
    A Methodology for parabolic synthesis of unary functions for hardware implementation2008In: SCS 2008, New York: Institute of Electrical and Electronics Engineers (IEEE), 2008Conference paper (Refereed)
    Abstract [en]

    This paper introduces a parabolic synthesis methodology for developing approximations of unary functions like trigonometric functions and logarithms which are specialized for efficient hardware mapped VLSI design. The advantages with the methodology are, short critical path, fast computation and high throughput enabled by a high degree of architectural parallelism. The feasibility of the methodology is shown by developing an approximation of the sine function for implementation in hardware. © 2008 IEEE

  • 38.
    Hertz, Erik
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Thuning, Niclas
    Lund University, Lund, Sweden.
    Bärring, Leo
    Lund University, Lund, Sweden.
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Nilsson, Peter
    Lund University, Lund, Sweden.
    Algorithms for implementing roots, inverse and inverse roots in hardware2016Manuscript (preprint) (Other academic)
    Abstract [en]

    In applications as in future MIMO communication systems a massive computation of complex matrix operations, such as QR decomposition, is performed. In these matrix operations, the functions roots, inverse and inverse roots are computed in large quantities. Therefore, to obtain high enough performance in such applications, efficient algorithms are highly important. Since these algorithms need to be realized in hardware it must also be ensured that they meet high requirements in terms of small chip area, low computation time and low power consumption. Power consumption is particularly important since many applications are battery powered.For most unary functions, directly applying an approximation methodology in a straightforward way will not lead to an efficient implementation. Instead, a dedicated algorithm often has to be developed. The functions roots, inverse and inverse roots are in this category. The developed approaches are founded on working in a floating-point format. For the roots functions also a change of number base is used. These procedures not only enable simpler solutions but also increased accuracy, since the approximation algorithm is performed on a mantissa of limited range.As a summarizing example the inverse square root is chosen. For comparison, the inverse square root is implemented using two methodologies: Harmonized Parabolic Synthesis and Newton-Raphson method. The novel methodology, Harmonized Parabolic Synthesis (HPS), is chosen since it has been demonstrated to provide very efficient approximations. The Newton-Raphson (NR) method is chosen since it is known for providing a very efficient implementation of the inverse square root. It is also commonly used in signal processing applications for computing approximations on fixed-point numbers of a limited range. Four implementations are made; HPS with 32 and 512 interpolation intervals and NR with 1 and 2 iterations. Summarizing the comparisons of the hardware performance, the implementations HPS 32, HPS 512 and NR 1 are comparable when it comes to hardware performance, while NR 2 is much worse. However, HPS 32 stands out in terms of better performance when it comes to the distribution of the error.

  • 39.
    Håkansson, Jesper
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Hansson, Jimmie
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Ökad flexibilitet i Anybus X-gateway med hjälp av Lua2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    HMS Networks AB develops, produces and sells communication technology for industrial automation. The product handles communication between a variety of protocols. The product treated in this project is an Anybus X-gateway Modbus-TCP Master/Client and this module is currently configured from a web-based interface. In doing so, the flexibility for handling protocols is limited to what the company chooses to add to the interface. Therefore the company had a request that the flexibility should be extended using a script language. The project has mainly consisted of two parts. The first part deals with the implementation of the script language Lua and the second part is about measurement and evaluation of the time required for the script. A prototype was developed with an operational implementation and successful results for data transmission. Although it was a successful project some optimizations are required if this solution is to replace the existing one, because script languages are not as fast as C. Some knowledge in programming and network is required to obtain an adequate understanding of the report.

  • 40.
    Johansson, Marcus
    Halmstad University, School of Information Technology.
    SQLite Carving och Analys: En jämförelse av metoder2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    SQLite filer används av ett flertal olika program för att spara viktig information.Information som kan vara viktig för forensiska utredningar, behovet att kunnaåterskapa SQLite filer är då ett växande bekymmer. Problemet med att återskapa SQLitefiler är att, till skillnad från andra filer så har SQLite filer inget definerat slut eller någonmarkör som visar var filen slutar. Detta arbete presenterar en ny metod att bestämmaslutet på SQLite filer och jämför denna metod mot den metod som används idag tillmesta del för att återskapa SQLite filer. För att jämföra dessa metoder utvecklades tvåprogram stpextr och blkextr. Blkextr är den metod som utvecklades under detta arbete.Stpextr visade sig vara snabbare och använda mindre arbetsminne än blkextr. Men ivissa sammanhang så kommer information gå förlorad när stpextr körs till skillnad från blkextr.

  • 41.
    Jonson, Jonas
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Thol, Albin
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Trådlös tryckmätning av roterande verktyg2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Embedded systems occurs increasingly in today’s society in everything from mobile phones to satellites. The technology development of today is towards more products communicating valuable data to its user and as components become smaller and cheaper they become easier to implement in existing products.

    The goal of this project was to add value to an already existing production tool in the wood industry. By including embedded technologies the tool is able to communicate valuable data to its user and thereby prevent accidents and optimize the production.

    The result of this project indicates that the implementation is possible despite rough environments, but in field testing and evaluation remains.

  • 42.
    Juneby, Hans
    et al.
    Halmstad University, School of Information Technology.
    Can, Mikael
    Halmstad University, School of Information Technology.
    Newtons andra vagn2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A problem of basic physics education in schools is that gravitation constantly interferes with experiments and demonstrations, making it difficult for students to understand Newton's first and second laws. The goal of this project is to improve the physics education in colleges and universities. To solve the problem we created a demonstration system that effectively demonstrates an inertial reference frame and Newton's second law by driving a specially designed train with constant velocity or constant acceleration. Students are able to perform three different experiments which are controlled via a webpage or by remote control, and analyse the output through plotted graphs. After extensive testing, the train and experiments proved successful and we concluded that physics education can be effectively improved with the help of practical experiments that students themselves can perform.

  • 43.
    Kandimalla, Jyothi Manju Bhargavi
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Vanam, Aditya
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Mathiyalagan, Prathap
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Wireless Network Connectivity Measure2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The efficiency to which a wireless multi node network is connected is generally measured by the probability that all the nodes are connected to a master node or connected to a master node via other connected node. The grade of connectivity measures how easily and reliably a packet sent by a node can reach another node. Our thesis work is aimed to find connectivity measurement between the nodes in a wireless multi node network. The result is investigated by randomly placing all the nodes in a given area of 38*38 meters and by estimating the connectivity of the whole network. The sub goals of the thesis are To Design a link metric To Find a Routing algorithm which provides information about neighboring nodesAchieving the expected results from this thesis work, it can be a contribution to the research in the measure of connectivity for a wireless multi-node network. By using the available routing algorithm and by setting up appropriate threshold for (i) Good connectivity (ii) Average connectivity (iii) bad connectivity, the status (connectivity measure) is informed to the master node (teacher node) in the network, so that the life time of the whole network is enhanced. Various results and solutions are provided and discussed for the above stated problem from the practical experiments.

  • 44.
    Karlsson, Erik
    Halmstad University, School of Information Technology.
    Automatisk aeroponisk odling2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today in farming of vegetables large amounts of water and pesticide are used, the farming is also weather and climate dependent and in Sweden the farming season is short. So, there is a need to make farming more efficient and determine how to make farming more stable and independent from unpredictable events.

    The goal of this project is to develop a prototype which make it possible to improve the resource usage and at the same time automate the process to increase the predictability. This project is going to use aeroponics which is way of growing in the air without soil and a single board computer is going to be used.

  • 45.
    Karlsson, Stefan
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Bigun, Josef
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Texture analysis of multiscale complex moments of the local power spectrum2005Report (Other academic)
  • 46.
    Khandeparkar, Satej
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Behavioral modelling of embedded software using execution traces2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Software updates made by developers often achieve their intendedpurpose, but these updates may also lead to an anomalous behaviorpreviously unknown to the developers. This might be due to theirinteraction with other parts of the system. If the developers had a toolwhich could help them to visually see these changes as a behavioralmodel, it would benefit them to actually know how the changes haveaffected the behavior of the system. Thus, empowering them to fixany side effects or bugs that arise as a part of their update.

    Thus, in order to visualize and compare learned behavioral models,a tool was created which would model the behavior from traces generatedby scenarios based on the related work in the area of inferringmodels of software systems. This tool was specifically intended forembedded software. So, to compare changes based on updates andfunctional changes of embedded software, behavioral models of scenarioswere obtained for different versions of a Real Time OperatingSystem (RTOS) Kernel. The visual comparison algorithm proved tobe effective in visualizing the differences between behavioral modelsfor a particular scenario across the versions.

  • 47.
    Lampoltshammer, Thomas J.
    et al.
    School of Information Technology and Systems Management, Salzburg University of Applied Sciences, Puch/Salzburg, Austria.
    Pignaton de Freitas, Edison
    Department of Applied Computing, Federal University of Santa Maria, Santa Maria, Brazil.
    Nowotny, Thomas
    School of Information Technology and Systems Management, Salzburg University of Applied Sciences, Puch/Salzburg, Austria.
    Plank, Stefan
    School of Information Technology and Systems Management, Salzburg University of Applied Sciences, Puch/Salzburg, Austria.
    Carvalho Lustosa da Costa, João Paulo
    Laboratory of Array Signal Processing, Department of Electrical Engineering, University of Brasilia, Campus Universitário Darcy Ribeiro, Brasília, Brazil.
    Larsson, Tony
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Heistracher, Thomas
    School of Information Technology and Systems Management, Salzburg University of Applied Sciences, Puch/Salzburg, Austria.
    Use of Local Intelligence to Reduce Energy Consumption of Wireless Sensor Nodes in Elderly Health Monitoring Systems2014In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, no 3, p. 4932-4947Article in journal (Refereed)
    Abstract [en]

    The percentage of elderly people in European countries is increasing. Such conjuncture affects socio-economic structures and creates demands for resourceful solutions, such as Ambient Assisted Living (AAL), which is a possible methodology to foster health care for elderly people. In this context, sensor-based devices play a leading role in surveying, e.g., health conditions of elderly people, to alert care personnel in case of an incident. However, the adoption of such devices strongly depends on the comfort of wearing the devices. In most cases, the bottleneck is the battery lifetime, which impacts the effectiveness of the system. In this paper we propose an approach to reduce the energy consumption of sensors’ by use of local sensors’ intelligence. By increasing the intelligence of the sensor node, a substantial decrease in the necessary communication payload can be achieved. The results show a significant potential to preserve energy and decrease the actual size of the sensor device units. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

  • 48.
    Larsson, Tony
    Telefonaktiebolaget L M Ericsson, Stockholm, Sweden.
    System and method for reducing coupling between modules in a telecommunications environment1997Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    A technique for enhancing the modifiability and reuse of telecommunications software systems is described. The problem domain is first partitioned into tasks that are assigned to distinct software program modules. In one embodiment, each of the software modules have multiple output ports. Each output port provides a mechanism to link the software module to a specific version of a different program module. The multiple output ports are used to selectively link the module to one of several versions of a different program module. The linking is performed as early as system design time or as late as run-time, or at any intermediate time between the two. The use of output ports makes software modules less dependent on each other and also simplifies the "hot-swapping" or dynamic replacement of one module by another at run-time. In an alternative embodiment, each of the software     modules has a unitary output port where each output port comprises an array of linking records. Each linking record has as many linking variables as there are versions of the receiving module.

  • 49.
    Larsson, Tony
    Telefonaktiebolaget L M Ericsson, Stockholm, Sweden.
    System and method for reducing coupling in an object-oriented programming environment1999Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The principal impediment to achieving interoperability, modifiability, implementation-independence and the reuse of object-oriented software components is the strong coupling between objects. The preferred solution to this problem involves adding an output port to each object and further making this additional output port part of a new software development approach that is an extension of the object-orientation paradigm. The resulting component-oriented software development environment provides the level of indirect addressing that is needed to manage the design requirements of interoperability, modifiability and implementation-independency. Another solution to the decoupling problem includes requiring each object to address other objects only indirectly, such as by using specific interface objects. Several variants of this technique have been detailed, described and compared in this patent application. Each of these techniques may be applied in different parts, or at different levels, of a software system.

  • 50.
    Larsson, Tony
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Jansson, Jonas
    VTI - Swedish National Road and Transport Research Institute, Linköping, Sweden.
    Grante, Christian
    Volvo AB, Göteborg, Sweden.
    Englund, Cristofer
    Viktoria Swedish ICT, Göteborg, Sweden.
    Cooperative partly automated and coordinated vehicles and transports2014Conference paper (Refereed)
    Abstract [en]

    Automation of vehicles and transports is rapidly evolving from a vision to reality due to systems for local situation awareness relying on advanced on-board vehicle sensors and software implemented intelligence. This evolution will be further supported by the capability to communicate and cooperate between vehicles and with important infrastructure to coordinate the traffic for both safe and environmentally efficient transports. To become accepted among vehicle drivers and other citizens this will require understanding of the problems involved and suitable methods to cope with these problems. This paper identifies some of the problems seen and methods needed.

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