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  • 301.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Mubeen, Saad
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Almeida, Luis
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    End-to-end Resource Reservations in Distributed Embedded Systems2016In: Proceedings - 2016 IEEE 22nd International Conference on Embedded and Real-Time Computing Systems and Applications, RTCSA 2016, 2016, 1-11 p., 7579921Conference paper (Refereed)
    Abstract [en]

    The resource reservation techniques provide effective means to lower the software complexity, ensure predictability and allow flexibility during the development and execution of complex distributed embedded systems. In this paper we propose a new end-to-end resource reservation model for distributed embedded systems. The model is comprehensive in such a way that it supports end-to-end resource reservations on distributed transactions with various activation patterns that are commonly used in industrial control systems. The model allows resource reservations on processors and real-time network protocols. We also present timing analysis for the distributed embedded systems that are developed using the proposed model. The timing analysis computes the end-to-end response times as well as delays such as data age and reaction delays. The presented analysis also supports real-time networks that can autonomously initiate transmissions. Such networks are not supported by the existing analyses. We also include a case study to show the usability of the model and end-to-end timing analysis with resource reservations.

  • 302.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Mubeen, Saad
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    End-to-end Resource Reservation Model2016Manuscript (preprint) (Other academic)
  • 303.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Patti, Gaetano
    University of Catania, Italy.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Alderisi, Giuliana
    University of Catania, Italy.
    Lo Bello, Lucia
    University of Catania, Italy.
    Schedulability Analysis of Ethernet Audio Video Bridging Networks with Scheduled Traffic Support2017In: Real-time systems, ISSN 0922-6443, E-ISSN 1573-1383, Vol. 53, no 4, 526-577 p.Article in journal (Refereed)
    Abstract [en]

    The IEEE Audio Video Bridging (AVB) technology is nowadays under consideration in several automation domains, such as, automotive, avionics, and industrial communications. AVB offers several benefits, such as open specifications, the existence of multiple providers of electronic components, and the real-time support, as AVB provides bounded latency to real-time traffic classes. In addition to the above mentioned properties, in the automotive domain, comparing with the existing in-vehicle networks, AVB offers significant advantages in terms of high bandwidth, significant reduction of cabling costs, thickness and weight, while meeting the challenging EMC/EMI requirements. Recently, an improvement of the AVB protocol, called the AVB ST, was proposed in the literature, which allows for supporting scheduled traffic, i.e., a class of time-sensitive traffic that requires time-driven transmission and low latency. In this paper, we present a schedulability analysis for the real-time traffic crossing through the AVB ST network. In addition, we formally prove that, if the bandwidth in the network is allocated according to the AVB standard, the schedulability test based on response time analysis will fail for most cases even if, in reality, these cases are schedulable. In order to provide guarantees based on analysis test a bandwidth over-reservation is required. In this paper, we propose a solution to obtain a minimized bandwidth over-reservation. To the best of our knowledge, this is the first attempt to formally spot the limitation and to propose a solution for overcoming it. The proposed analysis is applied to both the AVB standard and the AVB ST. The analysis results are compared with the results of several simulative assessments, obtained using OMNeT++, on both automotive and industrial case studies. The comparison between the results of the analysis and the simulation ones shows the effectiveness of the analysis proposed in this work.

  • 304.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Pedreiras, P.
    University of Aveiro, Aveiro, Portugal .
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Almeida, L.
    University of Porto, Porto, Portugal.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Evaluation of dynamic reconfiguration architecture in multi-hop switched ethernet networks2014In: 19th IEEE International Conference on Emerging Technologies and Factory Automation, ETFA 2014, 2014, Article number 7005322- p.Conference paper (Refereed)
    Abstract [en]

    On-the-fly adaptability and reconfigurability are recently becoming an interest in real-time communications. To assure a continued real-time behavior, the admission control with a quality-of-service mechanism is required, that screen all adaptation and reconfiguration requests. In the context of switched Ethernet networks, the FTT-SE protocol provides adaptive real-time communication. Recently, we proposed two methods to perform the online reconfiguration in multi-hop FTT-SE architectures. However, the methods lack the experimental evaluation. In this paper, we evaluate both methods in terms of the reconfiguration time. 

  • 305.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Pedreiras, P.
    DETI/IT, University of Aveiro, Aveiro, Portugal .
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bril, Reinder
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Technische Universiteit Eindhoven (TU/e), Netherlands .
    Almeida, L.
    Technische Universiteit Eindhoven (TU/e), Netherlands .
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Response time analysis of multi-hop HaRTES Ethernet Switch networks2014In: IEEE Int. Workshop Factory Commun. Syst. Proc. WFCS, 2014Conference paper (Refereed)
    Abstract [en]

    In this paper we focus on micro-segmented switched-Ethernet networks with HaRTES switches. HaRTES switches provide synchronous and asynchronous real-time traffic scheduling, dynamic Quality-of-Service adaptation and transparent integration of real-time and non-real-time nodes. Herein we investigate the challenges of connecting multiple HaRTES switches in order to build multi-hop communication and we propose a method, named Distributed Global Scheduling, to handle the traffic forwarding in such an architecture while preserving the unique properties of the single HaRTES switch case. Moreover, we develop a response time analysis for the method. We also evaluate the level of pessimism embodied in the anal-ysis. Finally, we show the applicability of the proposed method in an industrial setting by applying it in an automotive case study.

  • 306.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Pedreiras, Paulo
    University of Aveiro, Portugal.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Dynamic Reconfiguration in Multi-Hop Switched Ethernet Networks2014In: ACM SIGBED Review. Special Issue on 6th Workshop on Adaptive and Reconfigurable Embedded Systems (APRES 2014), ISSN 1551-3688, Vol. 11, no 3, 62-65 p.Article in journal (Refereed)
    Abstract [en]

    The FTT-SE protocol provides adaptive real-time communication on Ethernet networks. To assure a continued real-time behavior, FTT-SE integrates admission control with a quality-of-service mechanism, which screen all adaptation and reconfiguration requests, accepting only those that do not compromise the system timeliness. The adaptability and reconfigurability have been deeply studied in the case of single switch FTT-SE architectures, whereas the extension of that for the multi-hop FTT-SE architecture was not yet investigated. Therefore, in this paper we study the challenges of enabling dynamic reconfiguration in multi-hop FTT-SE networks, we propose two methods (one centralized and one distributed) and we present a qualitative comparison between them.

  • 307.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Pedreiras, Paulo
    University of Aveiro, Portugal.
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Supporting Multi-Hop Communications with HaRTES Ethernet Switches2013Conference paper (Refereed)
    Abstract [en]

    In this paper we identify the challenges of multi-hop communication when using a micro-segmented switched-Ethernet protocol with enhanced HaRTES switches. The HaRTES architecture has been explored in the scope of single-switch topology, and provides dynamic virtual channels that can be composed hierarchically and provide bounded latency together with temporal isolation. Herein we propose two different solutions regarding the traffic forwarding in multi-switch architectures, while maintaining the unique properties of the single HaRTES switch case. In the first approach, the traffic is buffered and scheduled sequentially in each hop. In the second solution the traffic is scheduled once and forwarded immediately through multiple switches without buffering. In this paper we present a brief comparison of both approaches and we report on the on-going work towards effective support to real-time communications in dynamic and complex Cyber-Physical Systems.

  • 308.
    Ashjaei, Mohammad
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. MRTC Malardalen Univ, Vasteras, Sweden..
    Silva, Luis
    DETI IT Univ Aveiro, Aveiro, Portugal..
    Behnam, Moris
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. MRTC Malardalen Univ, Vasteras, Sweden..
    Pedreiras, Paulo
    DETI IT Univ Aveiro, Aveiro, Portugal..
    Bril, Reinder J.
    Tech Univ Eindhoven TU E, Eindhoven, Netherlands..
    Almeida, Luis
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. MRTC Malardalen Univ, Vasteras, Sweden.;IT DEEC Univ Porto, Oporto, Portugal..
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. MRTC Malardalen Univ, Vasteras, Sweden..
    Improved Message Forwarding for Multi-Hop HaRTES Real-Time Ethernet Networks2016In: Journal of Signal Processing Systems, ISSN 1939-8018, E-ISSN 1939-8115, Vol. 84, no 1, 47-67 p.Article in journal (Refereed)
    Abstract [en]

    Nowadays, switched Ethernet networks are used in complex systems that encompass tens to hundreds of nodes and thousands of signals. Such scenarios require multi-switch architectures where communications frequently occur in multiple hops. In this paper we investigate techniques to allow efficient multi-hop communication using HaRTES switches. These are modified Ethernet switches that provide real-time traffic scheduling, dynamic bandwidth management and temporal isolation between real-time and non-real-time traffic. This paper addresses the problem of forwarding traffic in HaRTES networks. Two methods have been recently proposed, namely Distributed Global Scheduling (DGS) that buffers traffic between switches, and Reduced Buffering Scheme (RBS), that uses immediate forwarding. In this paper, we discuss the design and implementation of RBS within HaRTES and we carry out an experimental validation with a prototype implementation. Then, we carry out a comparison between RBS and DGS using worst-case response time analysis and simulation. The comparison clearly establishes the superiority of RBS concerning end-to-end response times. In fact, with sample message sets, we achieved reductions in end-to-end delay that were as high as 80 %.

  • 309.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalen University, School of Innovation, Design and Engineering.
    Extending FTT-SE protocol for Multi-Master/Multi-Slave Networks2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ethernet Switches are widely used in real-time distributed systems as a solution to guarantee the real-time behavior in communication. In this solution there are still some limitations which are the important obstacles obtaining timeliness in the network. These limitations are the limited number of priority levels as well as the possibility of memory overruns with consequent messages. The mentioned limitations can be eliminated using a master/slave technique along with FTT paradigm. The FTT-SE protocol which is a technique based on the master/slave and FTT methods was proposed to overcome the mentioned limitations. However, the FTT-SE protocol has been investigated for a small network architecture with a single switch and master node. Extension of this solution to larger networks is still an open issue. Three different architectures were suggested to scale the FTT-SE to large scale network. In this thesis we propose a solution that extends the FTT-SEprotocol while keeping the real-time behavior of the network. In this solution, we divided the network into a set of sub-networks, each contains one switch, set of slave nodes and one master node that connected to the associated switch in the network. Moreover, the switches are connected together directly without gateways and form a tree topology network. The solution includes both synchronous and asynchronous traffic in the network. We also show that the timeliness of the traffic can still be enforced. Moreover, to validate the solution we have designed and implemented a simulator based on the Matlab/Simulink which is a tool to evaluate different network architecture using Simulink blocks. All transmission can be visualized by the ordinary Scope block in the Simulink. Moreover, the end-to-end delay for all messages is calculated after the simulation running to show the response time of the network. Furthermore, the response time analysis is done for both synchronous and asynchronous messages in this thesis according to the proposed solution. The results from simulation and the analysis are compared together to validate the investigations.

  • 310.
    Ask, A
    Mälardalen University, School of Innovation, Design and Engineering.
    Flexible and Mobile Production – Demonstrator for Small Series Production Modules2006In: Proceedings of the 6th International Symposium on Tools and Methods for Competitive Engineering, TMCE, 18-22nd of April 2006, Ljubljana, Slovenia / [ed] Duhovnik, J., Horváth, I, 2006Conference paper (Refereed)
  • 311.
    Ask, Andréas
    et al.
    Mälardalen University, Department of Innovation, Design and Product Development.
    Jackson, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Factory-in-a-Box: An Enabler to Realize Mass Customization2006In: Proceedings of the international conference on agile manufacturing, ICAM 2006, 2006, 44-54 p.Conference paper (Refereed)
  • 312.
    Ask, P.
    et al.
    Department of Biomedical Engineering, Linköping University, Sweden.
    Ekstrand, K.
    ?.
    Hult, P.
    Department of Biomedical Engineering, Linköping University, Sweden.
    Lindén, Maria
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Pettersson, N. -E
    Örebro County Council, Sweden.
    NovaMedTech - A regional program for supporting new medical technologies in personalized health care2012In: Studies in Health Technology and Informatics, 2012, 71-75 p.Conference paper (Refereed)
    Abstract [en]

    NovaMedTech is an initiative funded from EU structural funds for supporting new medical technologies for personalized health care. It aims at bringing these technologies into clinical use and to the health care market. The program has participants from health care, industry and academia in East middle Sweden. The first three year period of the program was successful in terms of product concepts tried clinically, and number of products brought to a commercialization phase. Further, the program has led to a large number of scientific publications. Among projects supported, we can mention: Intelligent sensor networks; A digital pen to collect medical information about health status from patients; A web-based intelligent stethoscope; Methodologies to measure local blood flow and nutrition using optical techniques; Blood flow assessment from ankle pressure measurements; Technologies for pressure ulcer prevention; An IR thermometer for improved accuracy; A technique that identifies individuals prone to commit suicide among depressed patients; Detection of infectious disease using an electronic nose; Identification of the lactate threshold from breath; Obesity measurements using special software and MR camera; and An optical probe guided tumor resection. During the present three years period emphasis will be on entrepreneurial activities supporting the commercialization and bringing products to the market.

  • 313. Ask, Per
    et al.
    Ekstrand, Kristina
    Hult, Peter
    Lindén, Maria
    Mälardalen University, School of Innovation, Design and Engineering.
    Pettersson, Nils-Erik
    A regional program for supporting new medical technologies in personalized health care2012In: PHealth 2012, 2012, 71-75 p.Conference paper (Refereed)
  • 314.
    Ask, Per
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Hult, Peter
    Mälardalen University, School of Innovation, Design and Engineering.
    Lindén, Maria
    Mälardalen University, School of Innovation, Design and Engineering.
    Pettersson, Nils-Erik
    Mälardalen University, School of Innovation, Design and Engineering.
    Ekstrand, Kristina
    Mälardalen University, School of Innovation, Design and Engineering.
    NovaMedTechs satsning pa medicinsk teknik for individualiserad vard2011In: Svenska Lakaresallskapets riksstamma 2011, 30 Nov-2 Dec, Stockholm, Sweden, 2011Conference paper (Refereed)
  • 315.
    Askri, Anna
    Mälardalen University, School of Innovation, Design and Engineering.
    Analysis of material- & tied-up capital flow in Inbound2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis is performed on behalf of Volvo Group Trucks Operations Logistics Services in Eskilstuna, which is also the final part of the Master in Engineering program – Innovation, production and logistics at Mälardalen University.

    Logistics Services central warehouse in Eskilstuna ensures that parts are available all over the world, material is transported to the production facilities, packaging is available and vehicles are distributed to the dealers. The current need is to reduce costs and improve the production process at the Inbound department. The aim of this project has been to analyze the current flow of materials and tied-up capital in the inbound flow and give improvement suggestions on reducing lead times and the tied-up capital, as well as give suggestions on common performance metrics for all the sub departments at Inbound.

    The report is based on theoretical and empirical study, where the theory concerns the topics; logistics, lean philosophy and supply chain management. The empirical study was carried out by data collection through time measurements in the plant and by BEAT-report, observations and discussions with the operators, and interviews with production managers and process developers. The collected data was analyzed and the products in the flow were divided into groups, where the inbound material flow was mapped by the VSM tool. Product groups were analyzed by amount of received material reports, quantity, value and lead time, and the product groups that tied the highest value were defined as well as where in the flow the value was located. For each sub department calculations on production capacity and utilization were performed to analyze the current state and be able to compare the departments with each other. The interviews contributed with knowledge to create a reliable and valid SWOT analysis for each sub department at Inbound, where common factors could be defined concerning deviations, performance metrics and other hidden problems, but also opportunities.

    Finally, in this report the current state in the Inbound department has been analyzed. Products have been categorized into groups and the materials flow mapped. It has been defined where in the flow and how much value that is tied up, and by which product groups. Hidden problems and deviations have been brought up to surface. Improvement suggestions have been given concerning decreasing of lead times and the tied up value, and also suggestions on common performance metrics for all the sub departments have been given.

  • 316.
    Aslam, Mudassar
    Mälardalen University, School of Innovation, Design and Engineering. Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bringing Visibility in the Clouds: using Security, Transparency and Assurance Services2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The evolution of cloud computing allows the provisioning of IT resources over the Internet and promises many benefits for both - the service users and providers. Despite various benefits offered by cloud based services, many users hesitate in moving their IT systems to the cloud mainly due to many new security problems introduced by cloud environments. In fact, the characteristics of cloud computing become basis of new problems, for example, support of third party hosting introduces loss of user control on the hardware; similarly, on-demand availability requires reliance on complex and possibly insecure API interfaces; seamless scalability relies on the use of sub-providers; global access over public Internet exposes to broader attack surface; and use of shared resources for better resource utilization introduces isolation problems in a multi-tenant environment. These new security issues in addition to existing security challenges (that exist in today's classic IT environments) become major reasons for the lack of user trust in cloud based services categorized in Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS) or Infrastructure-as-a-Service (IaaS).

    The focus of this thesis is on IaaS model which allows users to lease IT resources (e.g. computing power, memory, storage, etc.) from a public cloud to create Virtual Machine (VM) instances. The public cloud deployment model considered in this thesis exhibits most elasticity (i.e. degree of freedom to lease/release IT resources according to user demand) but is least secure as compared to private or hybrid models. As a result, public clouds are not trusted for many use cases which involve processing of security critical data such as health records, financial data, government data, etc. However, public IaaS clouds can also be made trustworthy and viable for these use cases by providing better transparency and security assurance services for the user. In this thesis, we consider such assurance services and identify security aspects which are important for making public clouds trustworthy. Based upon our findings, we propose solutions which promise to improve cloud transparency thereby realizing trustworthy clouds.

    The solutions presented in this thesis mainly deal with the secure life cycle management of the user VM which include protocols and their implementation for secure VM launch and migration. The VM launch and migration solutions ensure that the user VM is always hosted on correct cloud platforms which are setup according to a profile that fulfills the use case relevant security requirements. This is done by using an automated platform security audit and certification mechanism which uses trusted computing and security automation techniques in an integrated solution. In addition to provide the assurance about the cloud platforms, we also propose a solution which provides assurance about the placement of user data in correct and approved geographical locations which is critical from many legal aspects and usually an important requirement of the user. Finally, the assurance solutions provided in this thesis increase cloud transparency which is important for user trust and to realize trustworthy clouds.

  • 317.
    Aslam, Mudassar
    Mälardalen University, School of Innovation, Design and Engineering.
    Secure Service Provisioning in a Public Cloud2012Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The evolution of cloud technologies which allows the provisioning of IT resources over the Internet promises many benefits for the individuals and enterprises alike. However, this new resource provisioning model comes with the security challenges which did not exist in the traditional resource procurement mechanisms. We focus on the possible security concerns of a cloud user (e.g. an organization, government department, etc.) to lease cloud services such as resources in the form of Virtual Machines (VM) from a public Infrastructure-as-a-Service (IaaS) provider. There are many security critical areas in the cloud systems, such as data confidentiality, resource integrity, service compliance, security audits etc. In this thesis, we focus on the security aspects which result in the trust deficit among the cloud stakeholders and hence hinder a security sensitive user to benefit from the opportunities offered by the cloud computing. Based upon our findings from the security requirements analysis,we propose solutions that enable user trust in the public IaaS clouds. Our solutions mainly deal with the secure life cycle management of the user VM which include mechanisms for VM launch and migration. The VM launch and migration solutions ensure that the user VM is always protected in the cloud by only allowing it to run on the user trusted platforms. This is done by using trusted computing techniques that allow the users to remotely attest and hence rate the cloud platforms trusted or untrusted. We also provide a prototype implementation to prove the implementation feasibility of the proposed trust enabling principles used in the VM launch and migration solutions.

  • 318.
    Aslam, Mudassar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Gehrmann, Christian
    Deploying Virtual Machines on Shared Platforms2011Report (Other (popular science, discussion, etc.))
    Abstract [en]

    In this report, we describe mechanisms for secure deployment of virtual machines on shared platforms looking into a telecommunication cloud use case, which is also presented in this report. The architecture we present focuses on the security requirements of the major stakeholders’ part of the scenario we present. This report comprehensively covers all major security aspects including different security mechanisms and protocols, leveraging existing standards and state-of-the art wherever applicable. In particular, our architecture uses TCG technologies for trust establishment in the deployment of operator virtual machines on shared resource platforms. We also propose a novel procedure for securely launching and cryptographically binding a virtual machine to a target platform thereby protecting the operator virtual machine and its related credentials.

  • 319.
    Aslam, Mudassar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Gehrmann, Christian
    TCG Based Approach for Secure Management of Virtualized Platforms: state-of-the-art2010Report (Other (popular science, discussion, etc.))
    Abstract [en]

    There is a strong trend shift in the favor of adopting virtualization to get business benefits. The provisioning of virtualized enterprise resources is one kind of many possible scenarios. Where virtualization promises clear advantages it also poses new security challenges which need to be addressed to gain stakeholders confidence in the dynamics of new environment. One important facet of these challenges is establishing 'Trust' which is a basic primitive for any viable business model. The Trusted computing group (TCG) offers technologies and mechanisms required to establish this trust in the target platforms. Moreover, TCG technologies enable protecting of sensitive data in rest and transit. This report explores the applicability of relevant TCG concepts to virtualize enterprise resources securely for provisioning, establish trust in the target platforms and securely manage these virtualized Trusted Platforms.

  • 320.
    Aslam, Mudassar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Gehrmann, Christian
    SICS Swedish ICT, Sweden.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    ASArP: Automated Security Assessment & Audit of Remote Platforms: using TCG-SCAP synergies2015In: Journal of Internet Services and Applications JISA-14, ISSN 1869-0238, Vol. 22, 28-39 p.Article in journal (Refereed)
    Abstract [en]

    Many enterprise solutions today are built upon complex distributed systems which are accessible to the users globally. Due to this global access, the security of the host platforms becomes critical. The platform administrators use security automation techniques such as those provided by Security Content Automation Protocol (SCAP) standards to protect the systems from the vulnerabilities that are reported daily; furthermore, they are responsible for keeping their systems compliant to the relevant security recommendations (governmental or industrial). Additionally, third party audit and certification processes are used to increase user trust in enterprise solutions. However, traditional audit and certification mechanisms are not continuous, that is, not frequent enough to deal with the daily reported vulnerabilities, and for that matter even auditors expect platform administrators to keep the systems updated. As a result, the end user is also forced to trust the platform administrators about the latest state of the platform. In this paper we develop an automated security audit and certification system (ASArP) which can be used by platform users or by third party auditors. We use security automation techniques for continuous monitoring of the platform security posture and make the results trustworthy by using trusted computing (TCG) techniques. The prototype development of ASArP validates the implementation feasibility; it also provides performance benchmarks which show that the ASArP based audit and certification can be done much more frequently (e.g. daily or weekly). The feasibility of ASArP based continuous audits is significantly better than traditional platform audits which are dependent on the physical presence of the auditors, thus making frequent audits much more expensive and operationally infeasible.

  • 321.
    Aslam, Mudassar
    et al.
    SICS Swedish ICT, Sweden.
    Gehrmann, Christian
    SICS Swedish ICT, Sweden.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Continuous Security Evaluation and Auditing of Remote Platforms by Combining Trusted Computing and Security Automation Techniques2013In: SIN 2013 - Proceedings of the 6th International Conference on Security of Information and Networks, 2013, 136-143 p.Conference paper (Refereed)
    Abstract [en]

    In many new distributed systems paradigms such a cloud computing, Internet of Things (IoT), electronic banking, etc. the security of the host platforms is very critical which is managed by the platform owner. The platform administrators use security automation techniques such as those provided by Security Content Automation Protocol (SCAP) standards to ensure that the outsourced platforms are set up correctly and follow the security recommendations (governmental or industry). However, the remote platform users still have to trust the platform administrators. The third party security audits, used to shift the required user trust from the platform owner to a trusted entity, are scheduled and are not very frequent to deal with the daily reported vulnerabilities which can be exploited by the attackers. In this paper we propose a remote platform evaluation mechanism which can be used by the remote platform users themselves, or by the auditors to perform frequent platform security audits for the platform users. We analyze the existing SCAP and trusted computing (TCG) standards for our solution, identify their shortcomings, and suggest ways to integrate them. Our proposed platform security evaluation framework uses the synergy of TCG and SCAP to address the limitations of each technology when used separately

  • 322.
    Aslam, Mudassar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Gehrmann, Christian
    Swedish Institute of Computer Science, Kista.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Security and Trust Preserving VM Migrations in Public Clouds2012In: Proceedings of the 11th IEEE International Conference onTrust, Security and Privacy in Computingand Communications (TrustCom-2012), IEEE Computer Society Digital Library, 2012, 869-876 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we consider the security and trustimplications of virtual machine (VM) migration from one cloudplatform to the other in an Infrastructure-as-a-Service (IaaS) cloud service model. We show how to extend and complement previous Trusted Computing techniques for secure VM launchto also cover the VM migration case. In particular, we propose a Trust_Token based VM migration protocol which guarantees that the user VM can only be migrated to a trustworthy cloud platform. Different from previous schemes, our solution is not dependent on an active (on-line) trusted third party. We show how our proposed mechanisms fulfill major security and trust requirements for secure VM migration in cloud environments.

  • 323.
    Aslam, Mudassar
    et al.
    Swedish Institute of Computer Science, Kista.
    Gehrmann, Christian
    Swedish Institute of Computer Science, Kista.
    Rasmusson, Lars
    Swedish Institute of Computer Science, Kista.
    Björkman, Mats
    Mälardalen University, School of Innovation, Design and Engineering.
    Securely Launching Virtual Machines on Trustworthy Platforms in a Public Cloud2012In: CLOSER 2012 - Proceedings of the 2nd International Conference on Cloud Computing and Services Science, 2012, 511-521 p.Conference paper (Refereed)
    Abstract [en]

    In this paper we consider the Infrastructure-as-a-Service (IaaS) cloud model which allows cloud users to run their own virtual machines (VMs) on available cloud computing resources. IaaS gives enterprises the possibility to outsource their process workloads with minimal effort and expense. However, one major problem with existing approaches of cloud leasing, is that the users can only get contractual guarantees regarding the integrity of the offered platforms. The fact that the IaaS user himself or herself cannot verify the provider promised cloud platform integrity, is a security risk which threatens to prevent the IaaS business in general. In this paper we address this issue and propose a novel secure VM launch protocol using Trusted Computing techniques. This protocol allows the cloud IaaS users to securely bind the VM to a trusted computer configuration such that the clear text VM only will run on a platform that has been booted into a trustworthy state. This capability builds user confidence and can serve as an important enabler for creating trust in public clouds. We evaluate the feasibility of our proposed protocol via a full scale system implementation and perform a system security analysis.

  • 324.
    Asp, Josefin
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Goldkuhl, Mathias
    Mälardalen University, School of Innovation, Design and Engineering.
    Industriellt innovationsfrämjande2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syfte: Syftet med studien är att undersöka hur företag inom industrin arbetar med innovationskraft och intraprenörskap från produktionspersonal i den operativa kärnan i samband med företagsstrukturen. Genom studien skall förbättringsområden för innovationsfrämjande inom intervjuade företag läggas fram.

    Metod: En kvalitativ metod med semistrukturerade intervjuer användes. Totalt 6 personer deltog i tre intervjuer på större industriföretag.

    Slutsats: Vi har sett en stor möjlighet att öka innovationskraften i de företag som samarbetats med. Detta genom att involvera all personal till att aktivt stimulera idéskapande och ge tid och positiv uppmärksamhet för innovationsarbete. Författarna har sett att det ständigt kommer många små förbättringsförslag från personal som jobbar nära produktionsprocessen då de ges möjlighet. Större företag behöver kontroll och detta kan skapa en motsträvighet att avsätta tid för innovationsarbete då det är osäkert vad resultaten kan bli. Ofta införs tidskrävande kontroller vilket ökar kostnader för innovationsarbete. För att minska kostnad och tid för förändringsarbete behövs en miljö som tillåter idéer och är decentraliserade där personalen har mandat att välja ut idéer och implementera dessa. För att göra detta krävs att personalen har den kunskap som behövs för att göra en förbättring utan negativa konsekvenser

  • 325.
    Asplund, Lars
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Johnson, B.
    Mälardalen University, School of Innovation, Design and Engineering.
    Lundqvist, Kristina
    Mälardalen University, School of Innovation, Design and Engineering.
    Burns, Alan
    Session Summary: The Ravenscar Profile and Implementation Issues1999In: ACM SIGAda Ada Letters, Vol. XIX, no 2, 12-14 p.Article in journal (Other academic)
  • 326.
    Asplund, Lars
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Lundqvist, Kristina
    Mälardalen University, School of Innovation, Design and Engineering.
    Safety Critical Systems Based on Formal Models2000In: ACM SIGAda Letters, ISSN 1094-3641, Vol. XX, no 4, 32-39 p.Article in journal (Refereed)
    Abstract [en]

    The Ravenscar profile for high integrity systems using Ada 95 is well defined in all real-time aspects. The complexity of the run-time system has been reduced to allow full utilization of formal methods for applications using the Ravenscar profile. In the Mana project a tool set is being developed including a formal model of a Ravenscar compliant run-time system, a gnat compatible run-time system, and an ASIS based tool to allow for the verification of a system including both COTS and code that is reused.

  • 327.
    Asplund, Lars
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Lundqvist, Kristina
    MIT, Cambridge, MA, United States .
    The Gurkh Project: A Framework for Verification and Execution of Mission Critical Applications2003In: AIAA/IEEE Digital Avionics Systems Conference - Proceedings, vol. 2, 2003, 10.B.1/1-10.B.1/9 p.Conference paper (Other academic)
    Abstract [en]

    The paper contributes with three methods that together will make a complete tool-set for verification of mission critical applications. The first method is the transformation of existing Ada or VHDL code into an intermediate form. This form is used for verification by numerous different model checkers. The second method is a predictable runtime kernel that has both a verifiable formal model and is implemented in hardware to achieve full predictability. Finally, a method for transforming the intermediate form of the complete system into a hardware unit, the SafetyChip that performs runtime control of the system. This SafetyChip can catch 'out-of-state' behaviors.

  • 328.
    Aspö, Ida
    Mälardalen University, School of Innovation, Design and Engineering.
    Illustration av blomväxters livscykel i ett handledningsmaterial för årskurs 4-92014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report, I explain how and what I have done to create an illustrated learning material that can explain the different events in the life cycle of flowering plants for pupils in grades 4-9. This has has been a collaboration between me and the Uppsala Botanical Garden. This material is meant to be used by teachers or personnel during visits at the Uppsala Botanical Garden to teach pupils about flowering plants. The information in the finished material include how the lifecycle of flowering plants might look like, how these plants can spread their seeds and how flowers are pollinated.To find out how to illustrate the important information of these evenets I have used principles of information design. A situational analysis and target audience analysis has also been conducted to investigate how this kind of learning materials might look like and under what conditions the pupils understand the information.

  • 329.
    Assadi, Pedram
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Pero Vesterlund, Daniel
    Mälardalen University, School of Innovation, Design and Engineering.
    Hårstad, Niklas
    Mälardalen University, School of Innovation, Design and Engineering.
    Implementering av PDCA i ett byggföretag: En metod att förbättra arbetsprocesser2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Genom ett eget utformat dokument av författarna baserat av PDCA-metoden, visar studiens utfall att implementering av innovationsteknik är fullt möjligt i ett byggföretag som Garant Bygg & Bad. PDCA-dokumentet främjar dessutom innovationsförmågan i förbättringsprocesser i det valda företaget. Till en början bör byggföretag fokusera på små förbättringar i innovationsarbetet, vilket är möjligt med PDCA-dokumentet. För att uppnå optimalt resultat av förbättringsverktyget PDCA anser författarna att vissa specifika punkter är avgörande. Dessa sammanfattas nedan:

    • Ledarskap. Ett tydligt ledarskap är nyckeln för att möjliggöra implementeringen av förbättringsdokumentet. Ledningen måste visa vilja, engagemang samt tydlighet. Det måste dessutom finnas en vilja till innovation från ledningen, att ta sig an problem och finna lösningar till dem. Detta eftersom ledningen har störst påverkan på medarbetarna och kan motivera dem.
    • Hög delaktighet i innovation. Vi tror att PDCA-dokumentet kommer bidra till högre delaktighet bland medarbetarna då fler blir involverade i olika testprojekt. Det är viktigt att organisationen måste inse fördelarna med att jobba med förbättringsprocesser, vilket ska resultera i värdeskapande.
    • Konkreta mål och delmål. Organisationen måste använda konkreta mål och delmål som ska uppfyllas gemensamt. På så sätt blir det enklare att skapa hög delaktighet och även viljan till innovation. Dessutom blir ledarskapet tydligare om vad som ska uppfyllas med PDCA-dokumentet.
    • Kultur. Det måste skapas en företagskultur som tillåter nya arbetssätt och delaktighet. Det ska även finnas en uppmuntran i kulturen att ta sig an nya förbättringsprojekt för att behålla förbättringsprocesser kontinuerligt.
    • Förstå PDCA-dokumentet och dess filosofi. För att förstå PDCA-dokumentet och dess filosofi är det nödvändigt med en introduktion av dokumentet och dess syfte. Om filosofin bakom metoden är förklarad kommer implementeringen av PDCA i organisationen att bli lättare.
  • 330.
    Astrand, Elaine
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Ekström, Mikael
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Extraction of working memory load and the importance of understanding the temporal dynamics2017In: International IEEE/EMBS Conference on Neural Engineering, NER, IEEE Computer Society , 2017, 641-647 p., 8008433Conference paper (Refereed)
    Abstract [en]

    Working memory processing is central for higher-order cognitive functions. Although the ability CP to access and extract working memory load has been proven feasible, the temporal resolution is low and cross-task generalization is poor. In this study, EEG oscillatory activity CP was recorded from sixteen healthy subjects while they performed two versions of the visual n-back task. Observed effects in the working memory-related EEG oscillatory activity CP, specifically in theta, alpha and low beta power, are significantly different in the two tasks (i.e. two categories of visual stimuli) and these differences are greatest after image onset. Furthermore, cross-task generalization can be obtained by concatenating both tasks and although similar performances are observed before and after image onset, this study highlights the complexity CP of working memory processing related to different categories of visual stimuli, particularly after image onset, that are crucial to understand, in order to interpret the extraction of working memory load.

  • 331.
    Astrand, Elaine
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Univ Lyon 1, Dept Neurosci Cognit, CNRS UMR 5229, Inst Sci Cognit Marc Jeannerod, 67 Blvd Pinel, F-69675 Bron, France.;Malardalen Univ, IDT, Hogskoleplan 1, S-72123 Vasteras, Sweden..
    Wardak, Claire
    Univ Lyon 1, Dept Neurosci Cognit, CNRS UMR 5229, Inst Sci Cognit Marc Jeannerod, 67 Blvd Pinel, F-69675 Bron, France..
    Baraduc, Pierre
    Univ Lyon 1, Dept Neurosci Cognit, CNRS UMR 5229, Inst Sci Cognit Marc Jeannerod, 67 Blvd Pinel, F-69675 Bron, France..
    Ben Hamed, Suliann
    Univ Lyon 1, Dept Neurosci Cognit, CNRS UMR 5229, Inst Sci Cognit Marc Jeannerod, 67 Blvd Pinel, F-69675 Bron, France..
    Direct Two-Dimensional Access to the Spatial Location of Covert Attention in Macaque Prefrontal Cortex2016In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 26, no 13, 1699-1704 p.Article in journal (Refereed)
    Abstract [en]

    Direct access to motor cortical information now enables tetraplegic patients to precisely control neuroprostheses and recover some autonomy. In contrast, explicit access to higher cortical cognitive functions, such as covert attention, has been missing. Indeed, this cognitive information, known only to the subject, can solely be inferred by an observer from the subject's overt behavior. Here, we present direct two-dimensional real-time access to where monkeys are covertly paying attention, using machine-learning decoding methods applied to their ongoing prefrontal cortical activity. Decoded attention was highly predictive of overt behavior in a cued target-detection task. Indeed, monkeys had a higher probability of detecting a visual stimulus as the distance between decoded attention and stimulus location decreased. This was true whether the visual stimulus was presented at the cued target location or at another distractor location. In error trials, in which the animals failed to detect the cued target stimulus, both the locations of attention and visual cue were misencoded. This misencoding coincided with a specific state of the prefrontal cortical population in which the shared variability between its different neurons (or noise correlations) was high, even before trial onset. This observation strongly suggests a functional link between high noise-correlation states and attentional failure. Overall, this real-time access to the attentional spotlight, as well as the identification of a neural signature of attentional lapses, open new perspectives both to the study of the neural bases of attention and to the remediation or enhancement of the attentional function using neurofeedback.

  • 332.
    Asztalos Morell, Ildikó
    et al.
    Mälardalen University, School of Health, Care and Social Welfare.
    Eriksson, Yvonne
    Mälardalen University, School of Innovation, Design and Engineering.
    Inledning2013In: Bilden av ingenjören / [ed] Yvonne Eriksson and Ildikó Asztalos Morell, Stockholm: Carlsson Bokförlag, 2013, 7-13 p.Chapter in book (Other academic)
  • 333.
    Atta, Zeid
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Hasan, Shuker
    Mälardalen University, School of Innovation, Design and Engineering.
    Automatisering av inmatningsprocess för armeringsjärn2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Comeco tillverkar manuella bockningsmaskiner för armeringsjärn som är upp till 40 mm tjocka. På marknaden idag finner man hel- och semiautomatiserade bockningsmaskiner men för dom är prislappen hög. Arbetsprocessen för operatören kan effektiviseras genom att automati-sera inmatningsprocessen för bockningsjärnet till Comecos manuella maskin. Dock är behovet för automatiseringen i form av ett externt tillägg. Utifrån en kartläggning av nödvändiga funkt-ioner som sedan förädlats i en produktutvecklingsprocess, till att bli komponenter. Har dessa sammanställts till en inmatningsmaskin som klarar av inmatningen av armeringsjärn som Comecos bockningsmaskin, B40-PLC, är avsedd för. Det innefattar även marknadens största längdstandard som är 12 m långa armeringsjärn. Inmatningsmaskinen är tänkt att vara en flexi-bel sammankoppling i en flödesprocess, som antigen kan vara manuell eller automatiserad. Valbarheten för hur automatiserad inmatningsprocessen ska vara, är då upp till användaren. Genom aktiv tillämplig av nödvändiga produktutvecklingsmetoder i processen som börjar med en undersökning av marknaden, till att forma koncept som är baserade på att lösa de nödvän-diga funktionerna, vilka vidare specificeras i produktgenereringsfasen. Komponenterna väljs och uppnår kraven genom att bland annat studera nödvändig teori för maskinelementen och grunda valen på hållfasthetslära och maskinelementsuträkningar.

    En Prototyp för maskinen har ej tagits fram. Vilket rekommenderas för att testa komponenter-nas samspel. Fördjupade studier för PLC-styrning tar ej plats i detta projekt och rekommende-ras för vidare studier och eventuella funktionella dataanpassningar till styrsystemet.

  • 334. Avdagic, Zikrija
    et al.
    Boskovic, Dusanka
    Causevic, Aida
    Mälardalen University, School of Innovation, Design and Engineering.
    Code Evaluation Using Fuzzy Logic2008Conference paper (Refereed)
    Abstract [en]

    This paper presents application of a fuzzy logic based system to automatically evaluate the

    maintainability of code. Code evaluation is accomplished by rating its quality provided with bad smells in

    code as inputs. Straightforward bad smells with existing software metrics tools are selected as inputs:

    duplicated code, long methods, large classes having a high cyclomatic complexity, or a large number of

    parameters and temporary fields. Removing these bad smells can result in significant code improvements

    concerning readability and maintainability. However, the precise definition of attributes like small, long, large

    or high is not clear, and their identification is rather subjective. Fuzzy logic values are suitable for capturing

    partial correspondence to attributes and fuzzy rules model have been used to describe the relation between bad

    smells and code quality. Model supporting the experimental evaluation of the fuzzy based code evaluation is

    implemented in Java.

    Key-Words: - Fuzzy Logic, Reasoning Systems, Refactoring, Bad Smells

  • 335.
    Avgerinou, M
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Andersson, Carina
    Mälardalen University, School of Innovation, Design and Engineering.
    Pettersson, R
    Spinillo, C
    The Virtual Nugget Simulator: Co-operative Learning, Games and Simulations for Online Communication2005Conference paper (Refereed)
  • 336. Avgerinou, M. D.
    et al.
    Andersson, Carina
    Mälardalen University, School of Innovation, Design and Engineering.
    Perceptions of qualities, roles, and functions: The online teacher perspective2006In: IADIS International Conference on Cognition and Exploratory Learning in Digital Age, CELDA 2006, 2006, 35-44 p.Conference paper (Refereed)
    Abstract [en]

    This qualitative study focuses on perceptions of emerging instructional roles and performance of online teachers from Sweden, and the USA. The purpose is to explore, understand, and perhaps explain how teachers experience, create, and establish their teaching personas, but also how they perceive and perform their role online. Qualitative data from participating teachers' surveys and interviews point at significant common threads running within and across the two groups despite the fact their respective academic environments are at critically different points on the online education continuum. Teachers' perceptions are in complete alignment with the four major roles of the online instructor, pedagogical, social, managerial, and technological (Bonk et al., 2001).

  • 337.
    Avigernou, Maria
    et al.
    Mälardalen University, School of Innovation, Design and Engineering. DePaul University, USA.
    Andersson, Carina
    Mälardalen University, School of Innovation, Design and Engineering.
    E-moderating Personas2007In: Quarterly Review of Distance Education, ISSN 1528-3518, Vol. 8, no 5, 353-364 p.Article in journal (Refereed)
    Abstract [en]

    The article presents a two-phase, comparative research study conducted by two university instructors whose research agenda concentrates on teacher perceptions of own qualities, roles, and functions in online instructional environments. The Phase 1 of the research compared and discussed the emerging instructional styles of participating online teachers, called e-moderators, and the Phase 2 focuses on the development of e-moderating personas representing identified behaviors, motivations and aspirations of real participants. Authors of the study found that persona modeling allows for data presentation in a narrative form enabling researcher to gain a holistic view of information.

  • 338.
    Avni, G.
    et al.
    IST Austria, Klosterneuburg, Austria.
    Goel, S.
    IIT Bombay, Mumbai, India.
    Henzinger, T. A.
    IST Austria, Klosterneuburg, Austria.
    Rodriguez-Navas, Guillermo
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Computing scores of forwarding schemes in switched networks with probabilistic faults2017In: Lecture Notes in Computer Science, Volume 10206, Springer Verlag , 2017, 169-187 p.Conference paper (Refereed)
    Abstract [en]

    Time-triggered switched networks are a deterministic communication infrastructure used by real-time distributed embedded systems. Due to the criticality of the applications running over them, developers need to ensure that end-to-end communication is dependable and predictable. Traditional approaches assume static networks that are not flexible to changes caused by reconfigurations or, more importantly, faults, which are dealt with in the application using redundancy. We adopt the concept of handling faults in the switches from non-real-time networks while maintaining the required predictability. We study a class of forwarding schemes that can handle various types of failures. We consider probabilistic failures. For a given network with a forwarding scheme and a constant ℓ, we compute the score of the scheme, namely the probability (induced by faults) that at least ℓ messages arrive on time. We reduce the scoring problem to a reachability problem on a Markov chain with a “product-like” structure. Its special structure allows us to reason about it symbolically, and reduce the scoring problem to #SAT. Our solution is generic and can be adapted to different networks and other contexts. Also, we show the computational complexity of the scoring problem is #P-complete, and we study methods to estimate the score. We evaluate the effectiveness of our techniques with an implementation.

  • 339.
    Avni, G.
    et al.
    IST Austria.
    Guha, S.
    Hebrew Univeristy; Israel.
    Rodriguez-Navas, Guillermo
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Synthesizing time-triggered schedules for switched networks with faulty links2016In: Proceedings of the 13th International Conference on Embedded Software, EMSOFT 2016, 2016, a26Conference paper (Refereed)
    Abstract [en]

    Time-triggered (TT) switched networks are a deterministic communication infrastructure used by real-time distributed embedded systems. These networks rely on the notion of globally discretized time (i.e. time slots) and a static TT schedule that prescribes which message is sent through which link at every time slot, such that all messages reach their destination before a global timeout. These schedules are generated offline, assuming a static network with fault-free links, and entrusting all error-handling functions to the end user. Assuming the network is static is an over-optimistic view, and indeed links tend to fail in practice. We study synthesis of TT schedules on a network in which links fail over time and we assume the switches run a very simple error-recovery protocol once they detect a crashed link. We address the problem of finding a pk; qresistant schedule; namely, one that, assuming the switches run a fixed error-recovery protocol, guarantees that the number of messages that arrive at their destination by the timeout is at least no matter what sequence of at most k links fail. Thus, we maintain the simplicity of the switches while giving a guarantee on the number of messages that meet the timeout. We show how a pk; q-resistant schedule can be obtained using a CEGAR-like approach: find a schedule, decide whether it is pk; q-resistant, and if it is not, use the witnessing fault sequence to generate a constraint that is added to the program. The newly added constraint disallows the schedule to be regenerated in a future iteration while also eliminating several other schedules that are not pk; q-resistant. We illustrate the applicability of our approach using an SMT-based implementation.

  • 340.
    Avritzer, Alberto
    et al.
    Siemens Corporate Research, United States .
    Rosa Maria, Meri Ledmundo de Souza e Silvaa
    Federal University of Rio de Janeiro, Brazil .
    Leao, RMM
    Federal University of Rio de Janeiro, Brazil .
    weyuker, elaine
    Mälardalen University, School of Innovation, Design and Engineering.
    Generating Test Cases Using using a Performability Model2011In: IET Software, ISSN 1751-8814, Vol. 5, no 2, 113-119 p.Article in journal (Refereed)
    Abstract [en]

    The authors present a new approach for the automated generation of test cases to be used for demonstrating the reliability of large industrial mission-critical systems. In this study they extend earlier work by using a performability model to track resource usage and resource failures. Results from the transient Markov chain analysis are used to estimate the software reliability at a given system execution time.

  • 341.
    Avén, Joakim
    Mälardalen University, School of Innovation, Design and Engineering.
    Analysis of the Z-wing configuration2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis will analyze the Z-wing configuration. The Z-wing configuration is basically an airplane that has one of the wings placed at the forward section of the fuselage and the other wing placed on the other side far aft at the fuselage.

    This configuration creates a lot of different and unwanted forces and moments due to a differential in lift and drag between both the wings and the main objective with this thesis is to get a Z-wing to fly straight and level flight without these strange and unwanted forces and moments over it.

    Therefore the contribution of the wings different parameters to different moments and forces have been mapped out. Parameters such as the angle of incidence, wing span, dihedral, placement of wings etc.

    All the calculations done regarding the aerodynamic forces on the Z-wing have been performed in the Tornado, which is a program that runs in MATLAB and uses Vortex Lattice Method for its calculations.

    The outcome was that a steady level flight was possible. The configuration does have a lot of disadvantages. It will be very difficult to control in pitch, yaw and roll, although a backwards sweep of the front wing and a backwards sweep of the aft wing made roll control much better.

  • 342.
    Awidesian, Johannes
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Persson, Mikael
    Mälardalen University, School of Innovation, Design and Engineering.
    Förbättringsarbete med bistånd av DMAIC-metoden: Ett pilotprojekt med utgångspunkt i kvalitetssäkring på Södergrens Br. Metallindustri2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete avser ett pilotprojekt utfört mellan månaderna januari och maj, 2015 på det karakteristiska legoföretaget Södergrens Br. Metallindustri AB i Eskilstuna. Pilotprojektets syfte är att redogöra hur Södergrens men framförallt andra karakteristiska legoföretag kan implementera och tillämpa förbättringsmetoden DMAIC, med målsättning att förbättra den allmänna kvalitén och således också nedbringa kvalitetsbristkostnader. För att göra detta genomförbart har man infört ett förbättringsprojekt på ett anpassat studieobjekt. Studieobjektet som utretts avser hanteringen av fixturer, mätdon och mätrum på Södergrens Br. Metallindustri. Datainsamlingen under pilotprojektet har utförts med hjälp av intervjuer, observationer, benchmarking och ett antal kvalitetsverktyg kopplade till DMAIC-metoden.

    Slutresultatet visar att Södergrens Br. Metallindustri och därav även andra legoföretag kan dra nytta av att implementera och tillämpa DMAIC för blivande förbättringsprojekt på företagen. Det som framförts under pilotprojektets gång stämmer överens med teori om implementering av DMAIC och anpassningsbara kvalitetsverktyg. Det som markant påverkar effektiviteten av förbättringsprojektet och således även anses vara mycket viktigt, är att utvald förbättringsgrupp har eller tilldelas rätt kunskap av DMAIC-metoden och allt därom. För att även försäkra att man väljer rätt förbättringsprojekt och få en sammankoppling mellan förbättringsgruppen är det viktigt att tillsammans formulera fram ett projektkontrakt med tillhörande mål och krav.

  • 343.
    Axell, Chritoffer
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Synenelius, Elvira
    Mälardalen University, School of Innovation, Design and Engineering.
    Björk, Magnus
    Mälardalen University, School of Innovation, Design and Engineering.
    Innovationsmäklare- ett nytt yrkeskoncept?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

                                 

    Idag väljer fler och fler att jobba med öppen innovation. Öppen innovation kan bidra till större kunskaps-inhämtning, mer kreativitet och mer kundanpassning under produktutvecklingen (Von Hippel, 2005).  För att få en innovationsprocess att fungera effektivt måste användarna av varan eller tjänsten få möjlighet att komma med synpunkter under utvecklingsfasen samt att processen bör hålla god hastighet (Von Hippel, 2005).

     

    I en öppen innovationsprocess blandas olika kompetenser och bakgrunder vilket leder till större kunskapsbreddning. När olika kunskaper möts kan de tillsammans utvecklas eller bygga vidare på varandra (Johansson, 2005). Att använda sig av öppen innovation kan bidra till att stärka organisationens ekonomiska resurser (Janssen, Bouwman, van Buuren & Haaker, 2014) (Harhoff, Henkel och Von Hippel, 2003). 

  • 344.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    A Transformation-Based Model of Evolutionary Architecting for Embedded System Product Lines2010In: Third International Workshop on Model Based Architecting and Construction of Embedded Systems, Oslo, 2010Conference paper (Refereed)
    Abstract [en]

    In many industries, embedded software plays an increasingly important role in defining the characteristics of the products. Often, a product line approach is used, and the system architecture is developed through evolution rather than being redone from scratch for each product. In this paper, we present a model of such an evolutionary process based on architecture transformations. The model attempts to give an accurate description of how real architects actually work. Key elements of the approach are how the transformations interact with consistency constraints and with feasibility in terms of resource limitations. The work is based on findings from previous case studies in the automotive industry. The model can be used to enhance our understanding of the architecting process, and to find ways to improve it.

  • 345.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Architectural Allocation Alternatives and Associated Concerns in Cyber-Physical Systems: A Case Study2015In: ECSAW '15 Proceedings of the 2015 European Conference on Software Architecture Workshops, 2015, Vol. Article No.15Conference paper (Refereed)
    Abstract [en]

    Cyber-physical systems is an extension of traditional embedded systems, where communication to the outside world is given more emphasis. This leads to a new design space also for software development, allowing new allocation strategies for functionality. In traditional embedded systems, all functionality was inside the product, but now it becomes possible to partition the software between the embedded systems and IT systems outside the product. This paper investigates, through a case study from the automotive domain, possible new allocation alternatives where computation is offloaded from the embedded system to a server, and what additional architectural concerns this leads to, including performance, resource utilization, robustness, and lifecycle aspects. In addition, the paper addresses new opportunities created by allocating functionality outside the embedded systems, and thus making data available for extended services, as well as the larger concerns that result on the organizational level, including new competency in architecture and DevOps.

  • 346.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    Evolutionary Architecting of Embedded and Enterprise Software and Systems2012In: Aligning Enterprise, System, and Software Architectures, IGI Global, 2012, 39-57 p.Chapter in book (Other academic)
    Abstract [en]

    Many industries rely heavily on embedded software and systems to maximize business value in their products. These systems are very complex and the architecture is important to control the complexity and make development efficient. There are often also connections between the embedded system and the different lifecycle processes, and hence to the enterprise systems supporting those processes. It is rare to start from scratch when developing new products, and instead these companies evolve their products over time, which means that architecting needs to be evolutionary. In this chapter, it is described what such an evolutionary architecting process can look like based on observations from industry, and how the process can be continuously improved using a maturity model. It is also presented how the embedded system relates to different elements of the enterprise architecture.

  • 347.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    Evolutionary Architecting of Embedded Automotive Product Lines: An Industrial Case Study2009In: Joint Working IEEE/IFIP Conference on Software Architecture (WICSA) & European Conference on Software Architecture (ECSA), Cambridge, UK, 2009, 101-110 p.Conference paper (Refereed)
    Abstract [en]

    In the automotive industry, embedded systems and software play an increasingly important role in defining the characteristics of the vehicles. Both the vehicles and the embedded systems are designed as product lines, and two distinct rchitecture processes can be identified. The revolutionary process develops the architecture of a new product line, and focuses on abstract quality attributes and flexibility. The evolutionary process continuously modifies the architecture due to changes, such as additions of new functionality. In this paper, the evolutionary process is investigated through a case study. The study reviews a number of changes to an existing architecture, observing the cause of the change, what quality attributes were considered, and what technical aspects were included. It is also analyzed how the interplay between the two processes can be improved through systematic feedback about what evolution actually takes place.

  • 348.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    Evolutionary Architecting of Software-Intensive Systems2012In: ERCIM News, ISSN 0926-4981, no 88, 24-25 p.Article in journal (Refereed)
    Abstract [en]

    Most industrial software-intensive systems have a very long life span, and undergo many changes after their initial conception. To ensure that they maintain the desired system-level properties, it is essential that their architecture is also updated to reflect the added functionality. To this end, we have investigated how Evolutionary Architecting should be carried out in order to provide a strong basis for a system, not only at conception but throughout its life. The results are concrete and based on empirical findings, and include both a new state-of-the-art process description and a light-weight maturity evaluation method.

  • 349.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    Improving the Evolutionary Architecting Process for Embedded System Product Lines2011In: 2011 IEEE International Systems Conference, SysCon 2011 - Proceedings, IEEE , 2011, 334-341 p.Conference paper (Refereed)
    Abstract [en]

    Many industries developing complex products based on embedded systems rely on architecting as a key activity. Furthermore, they use product line approaches to find synergies between their products. This means that they use a base platform which is adapted to different products, and the architecture of the product line thus evolves over time. In previous case studies we have seen that these companies often lack a defined process for the evolutionary architecting of these product lines. The contribution of this paper is to present such a process, which matches key characteristics of mature architecting practices. It is also discussed how this process compares to observations in industry.

  • 350.
    Axelsson, Jakob
    Mälardalen University, School of Innovation, Design and Engineering.
    On how to deal with uncertainty when architecting embedded software and systems2011In: Lecture Notes in Computer Science, vol. 6903, Springer-Verlag , 2011, 199-202 p.Chapter in book (Refereed)
    Abstract [en]

    This paper discusses the topic of uncertainty in the context of architecting embedded software and systems. It presents links between complexity and uncertainty, and identifies different kinds of uncertainty. Based on this, it elaborates why uncertainty arises in the architecting of software-intensive systems, and presents ten different tactics that can be employed to deal with uncertainty and mitigate the associated risks.

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