Ändra sökning
Avgränsa sökresultatet
3456789 251 - 300 av 2737
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 251.
    Back, Ralph-Johan
    et al.
    Turku Centre for Computer Science .
    Cerschi (Seceleanu), Cristina
    Turku Centre for Computer Science .
    Modeling and Verifying a Temperature Control System using Continuous Action Systems2000Konferensbidrag (Refereegranskat)
    Abstract [en]

    We formally describe and verify a real-time temperature control system for a nuclear reactor tank, using a generalization of action systems to hybrid systems (based on weakest precondition predicate transformer semantics) as our formal framework. The analyzed control system is a linear hybrid system, combining discrete control with continuous dynamics. Our work can be seen as a case study on the applicability of the hybrid action system formalism to study the reachability problem, i.e., to prove that an unsafe state can not be reached by executing the system.

  • 252.
    Back, Ralph-Johan
    et al.
    Turku Centre for Computer Science, Finland.
    Seceleanu, Cristina
    Turku Centre for Computer Science, Finland.
    Westerholm, Jan
    Turku Centre for Computer Science, Finland.
    Symbolic Simulation of Hybrid Systems2002Konferensbidrag (Refereegranskat)
    Abstract [en]

    Continuous action systems (CAS) is a formalism intended for modeling hybrid systems (systems that combine discrete control with continuous behavior), and proving properties about the model within refinement calculus. In this paper we use a symbolic manipulation program to build a tool for simulating CAS models by calculating symbolically the time evolution of the discrete and continuous CAS model functions, as explicit and exact expressions of a continuous time variable. We may then study the time behavior and general properties of the model by plotting these functions with respect to time. For certain models our tool eliminates the need for introducing tolerances into the model structure. The tool is useful for checking that the model behaves correctly, and we can sometimes study the behavior of CAS models with in principle infinite precision.

  • 253.
    Badiozamany, Sobhan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för datalogi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Real-time data stream clustering over sliding windows2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In many applications, e.g. urban traffic monitoring, stock trading, and industrial sensor data monitoring, clustering algorithms are applied on data streams in real-time to find current patterns. Here, sliding windows are commonly used as they capture concept drift.

    Real-time clustering over sliding windows is early detection of continuously evolving clusters as soon as they occur in the stream, which requires efficient maintenance of cluster memberships that change as windows slide.

    Data stream management systems (DSMSs) provide high-level query languages for searching and analyzing streaming data. In this thesis we extend a DSMS with a real-time data stream clustering framework called Generic 2-phase Continuous Summarization framework (G2CS).  G2CS modularizes data stream clustering by taking as input clustering algorithms which are expressed in terms of a number of functions and indexing structures. G2CS supports real-time clustering by efficient window sliding mechanism and algorithm transparent indexing. A particular challenge for real-time detection of a high number of rapidly evolving clusters is efficiency of window slides for clustering algorithms where deletion of expired data is not supported, e.g. BIRCH. To that end, G2CS includes a novel window maintenance mechanism called Sliding Binary Merge (SBM). To further improve real-time sliding performance, G2CS uses generation-based multi-dimensional indexing where indexing structures suitable for the clustering algorithms can be plugged-in.

  • 254.
    Bagheri, Maryam
    et al.
    Sharif University of Technology, Iran.
    Akkaya, Ilge
    University of California at Berkley, US.
    Khamespanah, Ehsan
    Reykjavik University, Iceland.
    Khakpour, Narges
    Linnaeus University, Sweden.
    Sirjani, Marjan
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Movaghar, Ali
    Sharif University of Technology, Iran.
    Lee, Edward
    University of California at Berkley, US.
    Coordinated Actors for Reliable Self-Adaptive Systems2016Ingår i: The 13th International Conference on Formal Aspects of Component Software FACS 2016, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Self-adaptive systems are systems that automatically adapt in response to environmental and internal changes, such as possible failures and variations in resource availability. Such systems are often realized by a MAPE-K feedback loop, where Monitor, Analyze, Plan and Execute components have access to a runtime model of the system and environment which is kept in the Knowledge component. In order to provide guarantees on the correctness of a self-adaptive system at runtime, the MAPE-K feedback loop needs to be extended with assurance techniques. To address this issue, we propose a coordinated actor-based approach to build a reusable and scalable model@runtime for self-adaptive systems in the domain of track-based traffic control systems. We demonstrate the approach by implementing an automated Air Traffic Control system (ATC) using Ptolemy tool.We compare different adaptation policies on the ATC model based on performance metrics and analyze combination of policies in different configurations of the model. We enriched our framework with runtime performance analysis such that for any unexpected change, subsequent behavior of the model is predicted and results are used for adaptation at the change-point. Moreover, the developed framework enables checking safety properties at runtime.

  • 255.
    Baig, Aftab
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ahmad, Iftikhar
    Mälardalens högskola, Akademin för innovation, design och teknik.
    A web store based on reusable .NET components2011Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The thesis project describes  the analysis, process and major factors in development of a simple component oriented Web Shop in ASP.NET. It addresses to the concepts used in  the application as  well  as  derivation  of  technical  design  and  development  from  the  concepts  acquired  by studying existing approaches.

    The report  describes  a  brief  summary of  existing  approaches  and related  technologies.  It also lays  the foundation  of  goal  oriented  approach  by  providing  an  overview  of  component  based  software engineering. The  basic  concepts for modularization  were  barrowed from  entities  identification,  object models and component models pplication’s architecture is set to be a layered app roach combining the software layered  architecture  approach  with  multi  tier  architecture  of  web  applications. Class models explaining the inner structure of each component have been provided and an overview of user interface pages is given to explain the application outer flow. The application sets out to prove the significance of component oriented approach as well as  the  support  provided for it by ASP.Net. The resulting package proves  to  have  scalable  components  that could be scaled for  or  reused in another  application or  in  a later version of the same application. 

  • 256.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Dowling, Jim
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Escrich, Pau
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Meseguer, Roc
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pietrosemoli, Ermanno
    The Abdus Salam International Centre for Theoretical Physics (ICTP). Trieste, Italy.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Zennaro, Marco
    The Abdus Salam International Centre for Theoretical Physics (ICTP). Trieste, Italy.
    Deploying Clouds in the Guifi Community Network2015Ingår i: Proceedings of the 2015 IFIP/IEEE International Symposium on Integrated Network Management, IM 2015, IEEE , 2015, 1020-1025 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes an operational geographically distributed and heterogeneous cloudinfrastructure with services and applications deployed in the Guifi community network. The presentedcloud is a particular case of a community cloud, developed according to the specific needs and conditions of community networks. We describe the concept of this community cloud, explain our technical choices for building it, and our experience with the deployment of this cloud. We review our solutions and experience on offering the different service models of cloud computing (IaaS, PaaS and SaaS) in community networks. The deployed cloud infrastructure aims to provide stable and attractive cloud services in order to encourage community network user to use, keep and extend it with new services and applications.

  • 257.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Khan, Amin M.
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Community clouds at the edge deployed in Guifi.net2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Community clouds are a cloud deployment model in which the cloud infrastructure is built with specific features for a community of users with shared concerns, goals, and interests. Commercialcommunity clouds already operate in several application areas such as in the finance, government and health, fulfilling community-specific requirements. In this demo, a community cloud for citizens is presented. It is formed by devices at the edge of the network, contributed by the members of acommunity network and brought together into a distributed community cloud system through the Cloudy distribution. The demonstration shows to the audience in a live access the deployedcommunity cloud from the perspective of the user, by accessing a Cloudy node, inspecting the services available in the community cloud, and showing the usage of some of its services.

  • 258.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Cloud-based community services in community networks2016Ingår i: 2016 International Conference on Computing, Networking and Communications, ICNC 2016, IEEE conference proceedings, 2016, 1-5 s., 7440621Konferensbidrag (Refereegranskat)
    Abstract [en]

    Wireless networks have shown to be a cost effective solution for an IP-based communication infrastructure in under-served areas. Services and application, if deployed within these wireless networks, add value for the users. This paper shows how cloud infrastructures have been made operational in a community wireless network, as a particular case of a community cloud, developed according to the specific requirements and conditions of the community. We describe the conditions and requirements of such a community cloud and explain our technical choices and experience in its deployment in the community network. The user take-up has started, and our case supports the tendency of cloud computing moving towards the network edge.

  • 259.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Community network clouds as a case for the IEEE Intercloud standardization2015Ingår i: 2015 IEEE Conference on Standards for Communications and Networking, CSCN 2015, 2015, 269-274 s., 7390456Konferensbidrag (Refereegranskat)
    Abstract [en]

    The IEEE P2302 Intercloud WG conducts work since 2011 on the project Standard for Intercloud Interoperability and Federation with the goal to define a standard architecture and building components for large-scale interoperability of independent cloud providers. While the standardization process has achieved fine-grained definitions of several Intercloud components, a deployment of the Intercloud to demonstrate the architectural feasibility is not yet operational. In this paper, we describe a deployed community network cloud and we show how it matches in several aspects the vision of the Intercloud. Similar to the Intercloud, the community network cloud consists of many small cloud providers, which for interoperability use a set of common services. In this sense, the community network cloud is a real use case for elements that the Intercloud standardization WG envisions, and can feed back to and even become part of the Intercloud. In fact, a study on Small or Medium Enterprise (SME) provided commercial services in the community network cloud indicates the importance of the success of the Intercloud standardization initiative for SMEs.

  • 260. Baird, Ryan
    et al.
    Gavin, Peter
    Själander, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Whalley, David
    Uh, Gang-Ryung
    Optimizing transfers of control in the static pipeline architecture2015Ingår i: Proc. 16th ACM SIGPLAN/SIGBED Conference on Languages, Compilers, and Tools for Embedded Systems, New York: ACM Press, 2015, 7-16 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Statically pipelined processors offer a new way to improve the performance beyond that of a traditional in-order pipeline while simultaneously reducing energy usage by enabling the compiler to control more fine-grained details of the program execution. This paper describes how a compiler can exploit the features of the static pipeline architecture to apply optimizations on transfers of control that are not possible on a conventional architecture. The optimizations presented in this paper include hoisting the target address calculations for branches, jumps, and calls out of loops, performing branch chaining between calls and jumps, hoisting the setting of return addresses out of loops, and exploiting conditional calls and returns. The benefits of performing these transfer of control optimizations include a 6.8% reduction in execution time and a 3.6% decrease in estimated energy usage.

  • 261.
    Bakhtyar, Shoaib
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Designing Electronic Waybill Solutions for Road Freight Transport2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In freight transportation, a waybill is an important document that contains essential information about a consignment. The focus of this thesis is on a multi-purpose electronic waybill (e-Waybill) service, which can provide the functions of a paper waybill, and which is capable of storing, at least, the information present in a paper waybill. In addition, the service can be used to support other existing Intelligent Transportation System (ITS) services by utilizing on synergies with the existing services. Additionally, information entities from the e-Waybill service are investigated for the purpose of knowledge-building concerning freight flows.

    A systematic review on state-of-the-art of the e-Waybill service reveals several limitations, such as limited focus on supporting ITS services. Five different conceptual e-Waybill solutions (that can be seen as abstract system designs for implementing the e-Waybill service) are proposed. The solutions are investigated for functional and technical requirements (non-functional requirements), which can potentially impose constraints on a potential system for implementing the e-Waybill service. Further, the service is investigated for information and functional synergies with other ITS services. For information synergy analysis, the required input information entities for different ITS services are identified; and if at least one information entity can be provided by an e-Waybill at the right location we regard it to be a synergy. Additionally, a service design method has been proposed for supporting the process of designing new ITS services, which primarily utilizes on functional synergies between the e-Waybill and different existing ITS services. The suggested method is applied for designing a new ITS service, i.e., the Liability Intelligent Transport System (LITS) service. The purpose of the LITS service isto support the process of identifying when and where a consignment has been damaged and who was responsible when the damage occurred. Furthermore, information entities from e-Waybills are utilized for building improved knowledge concerning freight flows. A freight and route estimation method has been proposed for building improved knowledge, e.g., in national road administrations, on the movement of trucks and freight.

    The results from this thesis can be used to support the choice of practical e-Waybill service implementation, which has the possibility to provide high synergy with ITS services. This may lead to a higher utilization of ITS services and more sustainable transport, e.g., in terms of reduced congestion and emissions. Furthermore, the implemented e-Waybill service can be an enabler for collecting consignment and traffic data and converting the data into useful traffic information. In particular, the service can lead to increasing amounts of digitally stored data about consignments, which can lead to improved knowledge on the movement of freight and trucks. The knowledge may be helpful when making decisions concerning road taxes, fees, and infrastructure investments.

  • 262.
    Bakhtyar, Shoaib
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Henesey, Lawrence
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Electronic Waybill Solutions: A Systemtic ReviewIngår i: Journal of Special Topics in Information Technology and Management, ISSN 1385-951X, E-ISSN 1573-7667Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    A critical component in freight transportation is the waybill, which is a transport document that has essential information about a consignment. Actors within the supply chain handle not only the freight but also vast amounts of information,which are often unclear due to various errors. An electronic waybill (e-Waybill) solution is an electronic replacement of the paper waybill in a better way, e.g., by ensuring error free storage and flow of information. In this paper, a systematic review using the snowball method is conducted to investigate the state-of-the-art of e-Waybill solutions. After performing three iterations of the snowball process,we identified eleven studies for further evaluation and analysis due to their strong relevancy. The studies are mapped in relation to each other and a classification of the e-Waybill solutions is constructed. Most of the studies identified from our review support the benefits of electronic documents including e-Waybills. Typically, most research papers reviewed support EDI (Electronic Documents Interchange) for implementing e-Waybills. However, limitations exist due to high costs that make it less affordable for small organizations. Recent studies point to alternative technologies that we have listed in this paper. Additionally in this paper, we present from our research that most studies focus on the administrative benefits, but few studies investigate the potential of e-Waybill information for achieving services, such as estimated time of arrival and real-time tracking and tracing.

  • 263.
    Balatinac, Ivan
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Radosevic, Iva
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Architecting for the cloud2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Cloud Computing is an emerging new computing paradigm which is developed out of service-orientation, grid computing, parallel computing, utility computing, autonomic computing, and virtualization paradigms. Both industry and academia have experienced its rapid growth and are exploring full usage of its potentials to maintain their services provided to customers and partners. In this context, a key aspect to investigate is how to architect or design cloud-based application that meet various system requirements of customers’ needs. In this thesis, we have applied the systematic literature review method to explore the main concerns when architecting for the cloud. We have identified, classified, and extracted existing approaches and solutions for specific concerns based on the existing research articles that focus on planning and providing cloud architecture or design for different concerns and needs. The main contribution of the thesis is a catalogued architecture solutions for managing specific concerns when architecting for the cloud.

  • 264.
    Baldini, Gianmarco
    et al.
    Institute for the Protection and Security of the Citizen (IPSC), Italy.
    Kounelis, Ioannis
    Institute for the Protection and Security of the Citizen (IPSC), Italy.
    Nai Fovino, Igor
    Institute for the Protection and Security of the Citizen (IPSC), Italy.
    Neisse, Ricardo
    Institute for the Protection and Security of the Citizen (IPSC), Italy.
    A Framework for Privacy Protection and Usage Control of Personal Data in a Smart City Scenario2013Ingår i: Critical Information Infrastructures Security: 8th International Workshop, CRITIS 2013, Amsterdam, The Netherlands, September 16-18, 2013, Revised Selected Papers, Springer Publishing Company, 2013, 212-217 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we address trust and privacy protection issues related to identity and personal data provided by citizens in a smart city environment. Our proposed solution combines identity management, trust negotiation, and usage control. We demonstrate our solution in a case study of a smart city during a crisis situation.

  • 265.
    Balliu, Musard
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Logics for Information Flow Security:From Specification to Verification2014Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Software is becoming  increasingly  ubiquitous and today we find software running everywhere. There is software driving our favorite  game  application or  inside the web portal we use to read the morning  news, and   when we book a vacation.  Being so commonplace, software has become an easy target to compromise  maliciously or at best to get it wrong. In fact, recent trends and highly-publicized attacks suggest that vulnerable software  is at  the root of many security attacks.     

    Information flow security is the research field that studies  methods and techniques to provide strong security guarantees against  software security attacks and vulnerabilities.  The goal of an  information flow analysis is to rigorously check how  sensitive information is used by the software application and ensure that this information does not escape the boundaries of the application, unless it is properly granted permission to do so by the security policy at hand.  This process can   be challenging asit first requires to determine what the applications security policy is and then to provide a mechanism  to enforce that policy against the  software application.  In this thesis  we address the problem of (information flow) policy specification and policy enforcement by leveraging formal methods, in particular logics and language-based analysis and verification techniques.

    The thesis contributes to the state of the art of information flow security in several directions, both theoretical and practical. On the policy specification side, we provide a  framework to reason about  information flow security conditions using the notion of knowledge. This is accompanied  by logics that  can be used  to express the security policies precisely in a syntactical manner. Also, we study the interplay between confidentiality and integrity  to enforce security in  presence of active attacks.  On the verification side, we provide several symbolic algorithms to effectively check whether an application adheres to the associated security policy. To achieve this,  we propose techniques  based on symbolic execution and first-order reasoning (SMT solving) to first extract a model of the target application and then verify it against the policy.  On the practical side, we provide  tool support by automating our techniques and  thereby making it possible  to verify programs written in Java or ARM machine code.  Besides the expected limitations, our case studies show that the tools can be used to  verify the security of several realistic scenarios.

    More specifically, the thesis consists of two parts and six chapters. We start with an introduction giving an overview of the research problems and the results of the thesis. Then we move to the specification part which  relies on knowledge-based reasoning and epistemic logics to specify state-based and trace-based information flow conditions and on the weakest precondition calculus to certify security in  presence of active attacks.  The second part of the thesis addresses the problem of verification  of the security policies introduced in the first part.  We use symbolic execution  and  SMT solving techniques to enable   model checking of the security properties.  In particular, we implement a tool that verifies noninterference  and declassification policies for Java programs. Finally, we conclude with relational verification of low level code, which is also supported by a tool.

  • 266.
    Balliu, Musard
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Dam, Mads
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Guanciale, Roberto
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Automating Information Flow Analysis of Low Level Code2014Ingår i: Proceedings of CCS’14, November 3–7, 2014, Scottsdale, Arizona, USA, Association for Computing Machinery (ACM), 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Low level code is challenging: It lacks structure, it uses jumps and symbolic addresses, the control ow is often highly optimized, and registers and memory locations may be reused in ways that make typing extremely challenging. Information ow properties create additional complications: They are hyperproperties relating multiple executions, and the possibility of interrupts and concurrency, and use of devices and features like memory-mapped I/O requires a departure from the usual initial-state nal-state account of noninterference. In this work we propose a novel approach to relational verication for machine code. Verication goals are expressed as equivalence of traces decorated with observation points. Relational verication conditions are propagated between observation points using symbolic execution, and discharged using rst-order reasoning. We have implemented an automated tool that integrates with SMT solvers to automate the verication task. The tool transforms ARMv7 binaries into an intermediate, architecture-independent format using the BAP toolset by means of a veried translator. We demonstrate the capabilities of the tool on a separation kernel system call handler, which mixes hand-written assembly with gcc-optimized output, a UART device driver and a crypto service modular exponentiation routine.

  • 267.
    Banaee, Hadi
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ahmed, Mobyen Uddin
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Loutfi, Amy
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Towards NLG for Physiological Data Monitoringwith Body Area Networks2013Ingår i: 14th European Workshop on Natural Language Generation, 2013, 193-197 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    This position paper presents an on-goingwork on a natural language generationframework that is particularly tailored fornatural language generation from bodyarea networks. We present an overview ofthe main challenges when considering thistype of sensor devices used for at homemonitoring of health parameters. The paperpresents the first steps towards the implementationof a system which collectsinformation from heart rate and respirationusing a wearable sensor.

  • 268.
    Bandaru, Vamsi Krishna
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Balasubramanian, Rajasekaran
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    OBJECT RECOGNITION USINGDIALOGUES AND SEMANTICANCHORING2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This report explains in detail the implemented system containing a robot and a sensor

    network that is deployed in a test apartment in an elderly residence area. The report

    focuses on the creation and maintenance (anchoring) of the connection between the

    semantic information present in the dialog with perceived actual physical objects in the

    home. Semantic knowledge about concepts and their correlations are retrieved from online

    resources and ontologies, e.g. Word-Net and sensors information are provided by

    cameras distributed in the apartment.

  • 269.
    Bao, Yan
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Programvaru- och datorsystem, SCS (Stängd 20120101).
    Brorsson, Mats
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Programvaru- och datorsystem, SCS (Stängd 20120101).
    An Implementation of Cache-Coherence for the Nios II ™ Soft-core processor2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Soft-core programmable processors mapped onto fieldprogrammable gate arrays (FPGA) can be considered as equivalents to a microcontroller. They combine central processing units (CPUs), caches, memories, and peripherals on a single chip. Soft-cores processors represent an increasingly common embedded software implementation option. Modern FPGA soft-cores are parameterized to support application-specific customization. However, these softcore processors are designed to be used in uniprocessor system, not for multiprocessor system. This project describes an implementation to solve the cache coherency problem in an ALTERA Nios II soft-core multiprocessor system.

  • 270. Bardizbanyan, Alen
    et al.
    Själander, Magnus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorarkitektur och datorkommunikation.
    Whalley, David
    Larsson-Edefors, Per
    Improving data access efficiency by using context-aware loads and stores2015Ingår i: Proc. 16th ACM SIGPLAN/SIGBED Conference on Languages, Compilers, and Tools for Embedded Systems, New York: ACM Press, 2015, 27-36 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Memory operations have a significant impact on both performance and energy usage even when an access hits in the level-one data cache (L1 DC). Load instructions in particular affect performance as they frequently result in stalls since the register to be loaded is often referenced before the data is available in the pipeline. L1 DC accesses also impact energy usage as they typically require significantly more energy than a register file access. Despite their impact on performance and energy usage, L1 DC accesses on most processors are performed in a general fashion without regard to the context in which the load or store operation is performed. We describe a set of techniques where the compiler enhances load and store instructions so that they can be executed with fewer stalls and/or enable the L1 DC to be accessed in a more energy-efficient manner. We show that using these techniques can simultaneously achieve a 6% gain in performance and a 43% reduction in L1 DC energy usage.

  • 271.
    Barf, Jochen
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Development and Implementation of an Image-Processing-Based Horizon Sensor for Sounding Rockets2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 272.
    Barkah, Dani
    et al.
    Volvo Construction Equipment AB, Eskilstuna, Sweden.
    Ermedahl, Andreas
    Mälardalens högskola, Institutionen för datavetenskap och elektronik.
    Gustafsson, Jan
    Mälardalens högskola, Institutionen för datavetenskap och elektronik.
    Lisper, Björn
    Mälardalens högskola, Institutionen för datavetenskap och elektronik.
    Sandberg, Christer
    Mälardalens högskola, Institutionen för datavetenskap och elektronik.
    Evaluation of Automatic Flow Analysis for WCET Calculation on Industrial Real-Time System Code2008Ingår i: Proceedings - Euromicro Conference on Real-Time Systems, 2008, 2008, 331-340 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    A static Worst-Case Execution Time (WCET) analysis derives upper bounds for the execution times of programs. Such analysts requires information about the possible program flows. The current practice is to provide this information manually, which can be laborious and error-prone. An alternative is to derive this information through an automated flow analysis. In this article, we present a case study where an automatic flowanalysis method was tested on industrial real-time system code. The same code was the subject of an earlier WCET case study, where it was analysed using manual annotations for the flow information. The purpose of the current study was to see to which extent the same flow information could be found automatically. The results show that for the most part this is indeed possible, and we could derive comparable WCET estimates using the automatically generated flow information. In addition, valuable insights were gained on what is needed to make flow analysis methods work on real production code. 

  • 273.
    Barkland, Lars-Erik
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Norder, Kim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    En studie av Scrum för två personer och utveckling av mobilt gränssnitt2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    En stor del av mjukvaruutveckling är den metod som styr flödet av den kreativaprocessen. Genom erfarenhet har det påvisats hur en brist på organisation kanha stora negativa effekter på utvecklingsarbetet och i slutändan produkten. Idetta arbete tillämpas Scrummetoden i en form för två personer och detanalyseras hur denna småskaliga version påverkar rollerna, artefakterna ochaktiviteterna associerade med originalscrum. Resultatet av arbetet med dennaanpassade version presenteras och vilka förändringar som skett jämfört medoriginalmetoden under tiden redovisas. Resultatet ihop med diskussionen visarpå en positiv effekt av användandet av en strukturerad utvecklingsmetod.På senare tid har användandet av enheter med mindre skärmar på Internet ökadi stort. Med denna förändring för gränssnitt kommer nya utmaningar i atthantera en stor variation av enheter. I processen av att utveckla enwebbapplikation analyserades teknikval för gränssnitt för mindre skärm därresponsiv design fanns vara bäst val utifrån relevanta förutsättningar.Designprinciper från konceptet responsiv design analyseras och tillämpandelösning redovisas.

  • 274. Barkowsky, M.
    et al.
    Wang, Kun
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Cousseau, R.
    Brunnstrom, K.
    Olsson, Roger
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Le Callet, P.
    Subjective quality assessment of error concealment strategies for 3DTV in the presence of asymmetric transmission errors2010Ingår i: Proceedings of 2010 IEEE 18th International Packet Video Workshop (PV, 2010, 193-200 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The transmission of 3DTV sequences over packet based networks may result in degradations of the video quality due to packet loss. In the conventional 2D case, several different strategies are known for extrapolating the missing information and thus concealing the error. In 3D however, the residual error after concealment of one view might leads to binocular rivalry with the correctly received second view. In this paper, three simple alternatives are presented: frame freezing, a reduced playback speed, and displaying only a single view for both eyes, thus effectively switching to 2D presentation. In a subjective experiment the performance in terms of quality of experience of the three methods is evaluated for different packet loss scenarios. Error-free encoded videos at different bit rates have been included as anchor conditions. The subjective experiment method contains special precautions for measuring the Quality of Experience (QoE) for 3D content and also contains an indicator for visual discomfort. The results indicate that switching to 2D is currently the best choice but difficulties with visual discomfort should be expected even for this method.

  • 275.
    Barkowsky, Marcus
    et al.
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Li, Jing
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Han, Taehwan
    Youn, Sungwook
    Ok, Jiheon
    Lee, Chulhee
    Hedberg, Christer
    Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Ananth, Indirajith Vijai
    Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Wang, Kun
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap. Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Brunnström, Kjell
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Dept. of Netlab, Acreo Swedish ICT AB, Sweden .
    Le Callet, Patrick
    LUNAM Université, Université de Nantes, IRCCyN UMR CNRS 6597, France .
    Towards standardized 3DTV QoE assessment: Cross-lab study on display technology and viewing environment parameters2013Ingår i: Proceedings of SPIE - The International Society for Optical Engineering, 2013, Art. no. 864809- s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Subjective assessment of Quality of Experience in stereoscopic 3D requires new guidelines for the environmental setup as existing standards such as ITU-R BT. 500 may no longer be appropriate. A first step is to perform cross-lab experiments in different viewing conditions on the same video sequences. Three international labs performed Absolute Category Rating studies on a freely available video database containing degradations that are mainly related to video quality degradations. Different conditions have been used in the labs: Passive polarized displays, active shutter displays, differences in viewing distance, the number of parallel viewers, and the voting device. Implicit variations were introduced due to the three different languages in Sweden, South Korea, and France. Although the obtained Mean Opinion Scores are comparable, slight differences occur in function of the video degradations and the viewing distance. An analysis on the statistical differences obtained between the MOS of the video sequences revealed that obtaining an equivalent number of differences may require more observers in some viewing conditions. It was also seen that the alignment of the meaning of the attributes used in Absolute Category Rating in different languages may be beneficial. Statistical analysis was performed showing influence of the viewing distance on votes and MOS results.

  • 276.
    Barriga, L.
    et al.
    KTH, Tidigare Institutioner, Teleinformatik.
    Brorsson, Mats
    Lund university.
    Ayani, Rassul
    KTH, Tidigare Institutioner, Teleinformatik.
    Hybrid Parallel Simulation of Distributed Shared-Memory Architectures1996Rapport (Övrigt vetenskapligt)
  • 277.
    Barriga, Luis
    et al.
    KTH, Tidigare Institutioner, Teleinformatik.
    Brorsson, Mats
    Lund university.
    Ayani, Rassul
    KTH, Tidigare Institutioner, Teleinformatik.
    A model for parallel simulation of distributed shared memory1996Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present an execution model for parallel simulation of a distributed shared memory architecture. The model captures the processor-memory interaction and abstracts the memory subsystem. Using this model we show how parallel, on-line, partially-ordered memory traces can be correctly predicted without interacting with the memory subsystem. We also outline a parallel optimistic memory simulator that uses these traces, finds a global order among all events, and returns correct data and timing to each processor. A first evaluation of the amount of concurrency that our model can extract for an ideal multiprocessor shows that processors may execute relatively long instruction sequences without violating the causality constraints. However parallel simulation efficiency is highly dependent on the memory consistency model and the application characteristics.

  • 278.
    Bartosz, Michalek
    et al.
    Katholieke Universiteit Leuven, Belgium .
    Weyns, Danny
    Katholieke Universiteit Leuven, Belgium .
    Towards a Solution for Change Impact Analysis of Software Product Line Products2011Ingår i: VARSA Workshop; Software Architecture (WICSA), 2011 9th Working IEEE/IFIP Conference on, IEEE Communications Society, 2011, 290-293 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Despite the fact that some practitioners and researchers report successful stories on Software ProductLines (SPL) adaptation, the evolution of SPL remains challenging. In our research we study a specific aspect of SPL adaptation, namely on updating of deployed products. Our particular focus is on the correct execution of updates and minimal interruption of services during the updates. The update process has two stages. First, the products affected by the evolution must be identified. We call this stage SPL-wide change impact analysis. In the second stage, each of the affected products has to be updated. In our previous work we have addressed the second stage of the update process. In this paper we report on our early results of the first stage: change impact analysis. We discuss how existing variability models can be employed to support automated identification of the products that require an update. The discussion is illustrated with the examples from an educational SPL that we are developing at K.U. Leuven.

  • 279.
    Barua, Shaibal
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahmed, Mobyen Uddin
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Begum, Shahina
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Classifying drivers' cognitive load using EEG signals2017Ingår i: Studies in Health Technology and Informatics, ISSN 0926-9630, E-ISSN 1879-8365, Vol. 237, 99-106 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A growing traffic safety issue is the effect of cognitive loading activities on traffic safety and driving performance. To monitor drivers' mental state, understanding cognitive load is important since while driving, performing cognitively loading secondary tasks, for example talking on the phone, can affect the performance in the primary task, i.e. driving. Electroencephalography (EEG) is one of the reliable measures of cognitive load that can detect the changes in instantaneous load and effect of cognitively loading secondary task. In this driving simulator study, 1-back task is carried out while the driver performs three different simulated driving scenarios. This paper presents an EEG based approach to classify a drivers' level of cognitive load using Case-Based Reasoning (CBR). The results show that for each individual scenario as well as using data combined from the different scenarios, CBR based system achieved approximately over 70% of classification accuracy. © 2017 The authors and IOS Press.

  • 280.
    Barua, Shaibal
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Begum, Shahina
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahmed, Mobyen Uddin
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Clustering based Approach for Automated EEG Artifacts Handling2015Ingår i: Frontiers in Artificial Intelligence and Applications, vol. 278, 2015, 7-16 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Electroencephalogram (EEG), measures the neural activity of the central nervous system, which is widely used in diagnosing brain activity and therefore plays a vital role in clinical and Brain-Computer Interface application. However, analysis of EEG signal is often complex since the signal recoding often contaminates with noises or artifacts such as ocular and muscle artifacts, which could mislead the diagnosis result. Therefore, to identify the artifacts from the EEG signal and handle it in a proper way is becoming an important and interesting research area. This paper presents an automated EEG artifacts handling approach, where it combines Independent Component Analysis (ICA) with a 2nd order clustering approach. Here, the 2nd order clustering approach combines the Hierarchical and Gaussian Picture Model clustering algorithm. The effectiveness of the proposed approach has been examined and observed on real EEG recording. According to result, the artifacts in the EEG signals are identified and removed successfully where the clean EEG signal shows acceptable considering visual inspection.

  • 281.
    Barua, Shaibal
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Begum, Shahina
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahmed, Mobyen Uddin
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Intelligent Automated EEG Artifacts Handling Using Wavelet Transform, Independent Component Analysis and Hierarchical clustering2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Billions of interconnected neurons are the building block of human brain. For each brain activity these neurons produce electrical signals or brain waves that can be obtained by the Electroencephalogram (EEG) recording. Due to the characteristics of EEG signal, recorded signal often contaminate with undesired physiological signals other than cerebral signal that refers to as EEG artifacts such as ocular or muscle artifacts. Therefore, identification of artifacts from the EEG signal and handle it in a proper way is becoming an important research area. This paper presents an automated EEG artifacts handling approach, where it combines Wavelet transform, Independent Component Analysis (ICA) with Hierarchical clustering method. The effectiveness of the proposed approach has been examined and observed on real EEG recording. According to result, the artifacts in the EEG signals are identified and removed successfully where after handling artifacts EEG signals show acceptable considering visual inspection.

  • 282.
    Barua, Shaibal
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Begum, Shahina
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahmed, Mobyen Uddin
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Supervised Machine Learning Algorithms to Diagnose Stress for Vehicle Drivers Based on Physiological Sensor Signals2015Ingår i: Studies in Health Technology and Informatics, Volume 211: Proceedings of the 12th International Conference on Wearable Micro and Nano Technologies for Personalized Health, 2–4 June 2015, Västerås, Sweden, 2015, Vol. 211, 241-248 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Machine learning algorithms play an important role in computer science research. Recent advancement in sensor data collection in clinical sciences lead to a complex, heterogeneous data processing and analysis for patient diagnosis and prognosis. Diagnosis and treatment of patients based on manual analysis of these sensor data is difficult and time consuming. Therefore, development of Knowledge-based systems to support clinicians in decision-making is important. However, it is necessary to perform experimental work to compare performances of different machine learning methods to help to select appropriate method for a specific characteristic of data sets. This paper compares classification performance of three popular machine learning methods i.e., case-based reasoning, neutral networks and support vector machine to diagnose stress of vehicle drivers using finger temperature and heart rate variability. The experimental results show that case-based reasoning outperforms other two methods in terms of classification accuracy. Case-based reasoning has achieved 80% and 86% accuracy to classify stress using finger temperature and heart rate variability. On contrary, both neural network and support vector machine have achieved less than 80% accuracy by using both physiological signals.

  • 283.
    Barua, Shaibal
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Begum, Shahina
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahmed, Mobyen Uddin
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ahlström, Christer
    The Swedish National Road and Transport Research Institute (VTI), Sweden.
    AUTOMATED EEG ARTIFACTS HANDLING FOR DRIVER SLEEPINESS MONITORING2016Ingår i: 2nd International Symposium on Somnolence, Vigilance, and Safety SomnoSafe2016, 2016Konferensbidrag (Refereegranskat)
  • 284.
    Bashir, Imran
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för datavetenskap, fysik och matematik, DFM.
    Visualizing Complex Data Using Timeline2012Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis  introduces the idea of visualizing complex data using timeline for problem solving and analyzing a huge database. The database contains information about vehicles, which are continuously sending information about driving behavior, current location, driver ativities etc. Data complexity can be resolved by data visualization where user can see this complex data in the abstract form of timeline visualization. visualize complex data by using timeline mgiht help to monitor and track diffrent time dependent activities. We developed web application to monitor and track monthly, weekly, and daily activities which helps in decision making and understanding complex data.

  • 285.
    Bashir, Shariq
    et al.
    Mohammad Ali Jinnah University, Islamabad, Pakistan.
    Afzal, Wasif
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Baig, Rauf
    Al Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia.
    Opinion-based entity ranking using learning to rank2016Ingår i: Applied Soft Computing, ISSN 1568-4946, E-ISSN 1872-9681, Vol. 38, nr 1, 151-163 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As social media and e-commerce on the Internet continue to grow, opinions have become one of the most important sources of information for users to base their future decisions on. Unfortunately, the large quantities of opinions make it difficult for an individual to comprehend and evaluate them all in a reasonable amount of time. The users have to read a large number of opinions of different entities before making any decision. Recently a new retrieval task in information retrieval known as Opinion-Based Entity Ranking (OpER) has emerged. OpER directly ranks relevantentities based on how well opinions on them are matched with a user's preferences that are given in the form of queries. With such a capability, users do not need to read a large number of opinions available for the entities. Previous research on OpER does not take into account the importance and subjectivity of query keywords in individual opinions of an entity. Entity relevance scores are computed primarily on the basis of occurrences of query keywords match, by assuming all opinions of an entity as a single field of text. Intuitively, entities that have positive judgments and strong relevance with query keywords should be ranked higher than those entities that have poor relevance and negative judgments. This paper outlines several ranking features and develops an intuitive framework for OpER in which entities are ranked according to how well individual opinions of entities are matched with the user's query keywords. As a useful ranking model may be constructed from many rankingfeatures, we apply learning to rank approach based on genetic programming (GP) to combine features in order to develop an effective retrieval model for OpER task. The proposed approach is evaluated on two collections and is found to be significantly more effective than the standard OpER approach.

  • 286. Basirat, Ali
    et al.
    Faili, Heshaam
    Bridge the gap between statistical and hand-crafted grammars2013Ingår i: Computer speech & language (Print), ISSN 0885-2308, E-ISSN 1095-8363, Vol. 27, nr 5, 1085-1104 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    LTAG is a rich formalism for performing NLP tasks such as semantic interpretation, parsing, machine translation and information retrieval. Depend on the specific NLP task, different kinds of LTAGs for a language may be developed. Each of these LTAGs is enriched with some specific features such as semantic representation and statistical information that make them suitable to be used in that task. The distribution of these capabilities among the LTAGs makes it difficult to get the benefit from all of them in NLP applications.

    This paper discusses a statistical model to bridge between two kinds LTAGs for a natural language in order to benefit from the capabilities of both kinds. To do so, an HMM was trained that links an elementary tree sequence of a source LTAG onto an elementary tree sequence of a target LTAG. Training was performed by using the standard HMM training algorithm called Baum–Welch. To lead the training algorithm to a better solution, the initial state of the HMM was also trained by a novel EM-based semi-supervised bootstrapping algorithm.

    The model was tested on two English LTAGs, XTAG (XTAG-Group, 2001) and MICA's grammar (Bangalore et al., 2009) as the target and source LTAGs, respectively. The empirical results confirm that the model can provide a satisfactory way for linking these LTAGs to share their capabilities together.

  • 287.
    Basirat, Ali
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Språkvetenskapliga fakulteten, Institutionen för lingvistik och filologi.
    Nivre, Joakim
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Språkvetenskapliga fakulteten, Institutionen för lingvistik och filologi.
    Greedy Universal Dependency Parsing with Right Singular Word Vectors2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    A set of continuous feature vectors formed by right singular vectors of a transformed co-occurrence matrix are used with the Stanford neural dependency parser to train parsing models for a limited number of languages in the corpus of universal dependencies. We show that the feature vector can help the parser to remain greedy and be as accurate as (or even more accurate than) some other greedy and non-greedy parsers.

  • 288.
    Baskar, Jayalakshmi
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Lindgren, Helena
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Human-Agent Dialogues on Health Topics - An Evaluation Study2015Ingår i: Highlights of practical applications of agents, multi-agent systems, and sustainability: The PAAMS Collection, PAAMS 2015, 2015, 28-39 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    A common conversation between an older adult and a nurse about health-related issues includes topics such as troubles with sleep, reasons for walking around nighttime, pain conditions, etc. This dialogue emerges from the participating human's lines of thinking, their roles, needs and motives, while switching between topics as the dialogue unfolds. This paper presents a dialogue system that enables a human to engage in a dialogue with a software agent to reason about health-related issues in a home environment. The purpose of this work is to conduct a pilot evaluation study of a prototype system for human-agent dialogues, which is built upon a set of semantic models and integrated in a web application designed for older adults. Focus of the study was to receive qualitative results regarding purpose and content of the agent-based dialogue system, and to evaluate a method for the agent to evaluate its behavior based on the human agent's perception of appropriateness of moves. The participants include five therapists and 11 older adults. The results show users' feedback on the purpose of dialogues and the appropriateness of dialogues presented to them during the interaction with the software agent.

  • 289.
    Baucke, Stephan
    et al.
    Ericsson Research, Germany.
    Grinnemo, Karl-Johan
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för datavetenskap.
    Ludwig, Reiner
    Ericsson Research, Germany.
    Brunström, Anna
    Karlstads universitet, Fakulteten för ekonomi, kommunikation och IT, Avdelningen för datavetenskap.
    Wolisz, Adam
    Department of Electrical Engineering, Technical University Berlin, Germany.
    Using Relaxed Timer Backoff to Reduce SCTP Failover TimesManuskript (Övrigt vetenskapligt)
  • 290.
    Baumann, Christoph
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Schwarz, Oliver
    RISE SICS.
    Dam, Mads
    KTH, Skolan för datavetenskap och kommunikation (CSC), Teoretisk datalogi, TCS.
    Compositional Verification of Security Properties for Embedded Execution Platforms2017Ingår i: PROOFS 2017: 6th International Workshop on Security Proofs for Embedded Systems / [ed] Ulrich Kühne and Jean-Luc Danger and Sylvain Guilley, 2017, Vol. 49, 1-16 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The security of embedded systems can be dramatically improved through the use of formally verified isolation mechanisms such as separation kernels, hypervisors, or microkernels. For trustworthiness, particularly for system level behaviour, the verifications need precise models of the underlying hardware. Such models are hard to attain, highly complex, and proofs of their security properties may not easily apply to similar but different platforms. This may render verification economically infeasible. To address these issues, we propose a compositional top-down approach to embedded system specification and verification, where the system-on-chip is modeled as a network of distributed automata communicating via paired synchronous message passing. Using abstract specifications for each component allows to delay the development of detailed models for cores, devices, etc., while still being able to verify high level security properties like integrity and confidentiality, and soundly refine the result for different instantiations of the abstract components at a later stage. As a case study, we apply this methodology to the verification of information flow security for an industry scale security-oriented hypervisor on the ARMv8-A platform. The hypervisor statically assigns (multiple) cores to each guest system and implements a rudimentary, but usable, inter guest communication discipline. We have completed a pen-and-paper security proof for the hypervisor down to state transition level and report on a partially completed verification of guest mode security in the HOL4 theorem prover.

  • 291.
    Baumgart, Stephan
    et al.
    Volvo Construction Equipment, Eskilstuna, Sweden.
    Fröberg, Joakim
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Punnekkat, Sasikumar
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. BIT-Pilani KK Birla Goa Campus, India.
    Enhancing Model-Based Engineering of Product Lines by Adding Functional Safety2015Ingår i: CEUR Workshop Proceedings, vol. 1487, 2015, 53-62 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Today's industrial product lines in the automotive and construction equipment domain face the challenge to show functional safety standard compliance and argue for the absence of failures for all derived product variants. The product line approaches are not su cient to support practitioners to trace safety-related characteristics through development. We aim to provide aid in creating a safety case for a certain con guration in a product line such that overall less e ort is necessary for each con guration. In this paper we 1) discuss the impact of functional safety on product line development, 2) propose a model-based approach to capture safety-related characteristics during concept phase for product lines and 3) analyze the usefulness of our proposal.

  • 292.
    Baumgart, Stephan
    et al.
    Volvo Construction Equipment, Eskilstuna, Sweden.
    Fröberg, Joakim
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Punnekkat, Susikumar
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Analyzing Hazards in System-of-Systems: Described in a Quarry Site Automation Context2017Ingår i: 11th Annual IEEE International Systems conference SysCon, 2017, 544-551 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Methods for analyzing hazards related to individual systems are well studied and established in industry today. When system-of-systems are set up to achieve new emergent behavior, hazards specifically caused by malfunctioning behavior of the complex interactions between the involved systems may not be revealed by just analyzing single system hazards. A structured process is required to reduce the complexity to enable identification of hazards when designing system-of-systems. In this paper we first present how hazards are identified and analyzed using hazard and risk assessment (HARA) methodology by the industry in the context of single systems. We describe systems-of-systems and provide a quarry site automation example from the construction equipment domain. We propose a new structured process for identifying potential hazards in systems-of-systems (HISoS), exemplified in the context of the provided example. Our approach helps to streamline the hazard analysis process in an efficient manner thus helping faster certification of system-of-systems.

  • 293.
    Baumgart, Stephan
    et al.
    Volvo Construction Equipment, Eskilstuna, Sweden.
    Parmeza, Ditmar
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Predicting the Effort for Functional Safety in Product Lines2015Ingår i: The 41st Euromicro Conference on Software Engineering and Advanced Applications SEAA'15, 2015Konferensbidrag (Refereegranskat)
  • 294.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dasari, Dakshina
    Research and Technology Centre, Robert Bosch, India.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    MECHAniSer - A Timing Analysis and Synthesis Tool for Multi-Rate Effect Chains with Job-Level Dependencies2016Ingår i: 7th International Workshop on Analysis Tools and Methodologies for Embedded and Real-time Systems WATERS'16, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Many industrial embedded systems have timing con- straints on the data propagation through a chain of independent tasks. These tasks can execute at different periods which leads to under and oversampling of data. In such situations, understand- ing and validating the temporal correctness of end-to-end delays is not trivial. Many industrial areas further face distributed development where different functionalities are integrated on the same platform after the development process. The large effect of scheduling decisions on the end-to-end delays can lead to expensive redesigns of software parts due to the lack of analysis at early design stages. Job-level dependencies is one solution for this challenge and means of scheduling such systems are available. In this paper we present MECHAniSer, a tool targeting the early analysis of end-to-end delays in multi-rate cause effect chains with specified job-level dependencies. The tool further provides the possibility to synthesize job-level dependencies for a set of cause-effect chains in a way such that all end-to-end requirements are met. The usability and applicability of the tool to industrial problems is demonstrated via a case study.

  • 295.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dasari, Dakshina
    Robert Bosch GmbH, Renningen, Germany.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Timing Analysis and Synthesis of Mixed Multi-Rate Effect Chains in MECHAniSer2016Ingår i: Open Demo Session of Real-Time Systems located at Real Time Systems Symposium (RTSS) RTSS@Work 2016, 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    The majority of embedded control systems are modeled with several chains of independently triggered tasks, also known as multi-rate effect chains. These chains have often stringent end-to-end timing requirements that should be satisfied before running the system. MECHAniSer is one of the tools that supports end-to-end timing analysis of such chains. In addition, the tool provides the possibility to synthesize job-level dependencies for these chains such that all end-to-end timing requirements are satisfied. In this paper we showcase an extension of MECHAniSer that supports the analysis of mixed chains that contain a mix of independent and dependent tasks.

  • 296.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dasari, Dakshina
    Research and Technology Centre, Robert Bosch, India.
    Nicolic, Borislav
    CISTER, INESC-TEC, ISEP, Portugal .
    Åkesson, Benny
    CISTER, INESC-TEC, ISEP, Portugal .
    Nélis, Vincent
    CISTER/INESC-TEC, ISEP, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Contention-Free Execution of Automotive Applications on a Clustered Many-Core Platform2016Ingår i: 28th Euromicro Conference on Real-Time Systems ECRTS'16, Toulouse, France, 2016, 14-24 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Next generations of compute-intensive real-time applications in automotive systems will require more powerful computing platforms. One promising power-efficient solution for such applications is to use clustered many-core architectures. However, ensuring that real-time requirements are satisfied in the presence of contention in shared resources, such as memories, remains an open issue. This work presents a novel contention-free execution framework to execute automotive applications on such platforms. Privatization of memory banks together with defined access phases to shared memory resources is the backbone of the framework. An Integer Linear Programming (ILP) formulation is presented to find the optimal time-triggered schedule for the on-core execution as well as for the access to shared memory. Additionally a heuristic solution is presented that generates the schedule in a fraction of the time required by the ILP. Extensive evaluations show that the proposed heuristic performs only 0.5% away from the optimal solution while it outperforms a baseline heuristic by 67%. The applicability of the approach to industrially sized problems is demonstrated in a case study of a software for Engine Management Systems.

  • 297.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Liu, Meng
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Adaptive Routing of Real-Time Traffic on a 2D-Mesh Based NoC2015Ingår i: The 21st IEEE International Conference on Embedded and Real-Time Computing Systems and Applications, WiP RTCSA-wip'15, 2015Konferensbidrag (Refereegranskat)
  • 298.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Extending Automotive Legacy Systems with Existing End-to-End Timing Constraints2017Ingår i: 14th International Conference on Information Technology : New Generations ITNG'17, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Developing automotive software is becoming in- creasingly challenging due to continuous increase in its size and complexity. The development challenge is amplified when the industrial requirements dictate extensions to the legacy (previously developed) automotive software while requiring to meet the existing timing requirements. To cope with these challenges, sufficient techniques and tooling to support the modeling and timing analysis of such systems at earlier development phases is needed. Within this context, we focus on the extension of software component chains in the software architectures of automotive legacy systems. Selecting the sampling frequency, i.e. period, for newly added software components is crucial to meet the timing requirements of the chains. The challenges in selecting periods are identified. It is further shown how to automatically assign periods to software components, such that the end-to-end timing requirements are met while the runtime overhead is minimized. An industrial case study is presented that demonstrates the applicability of the proposed solution to industrial problems.

  • 299.
    Becker, Matthias
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nicolic, Borislav
    Technische Universität Braunschweig, Germany.
    Dasari, Dakshina
    Robert Bosch GmbH, Renningen, Germany.
    Åkesson, Benny
    CISTER/INESC-TEC, ISEP, Portugal.
    Nélis, Vincent
    CISTER/INESC-TEC, ISEP, Portugal.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Partitioning and Analysis of the Network-on-Chip on a COTS Many-Core Platform2017Ingår i: 23rd IEEE Real-Time and Embedded Technology and Applications Symposium RTAS'17, 2017, 101-112 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Many-core processors can provide the computational power required by future complex embedded systems. However, their adoption is not trivial, since several sources of interference on COTS many-core platforms have adverse effects on the resulting performance. One main source of performance degradation is the contention on the Network-on-Chip, which is used for communication among the compute cores via the off- chip memory. Available analysis techniques for the traversal time of messages on the NoC do not consider many of the architectural features found on COTS platforms. In this work, we target a state-of-the-art many-core processor, the Kalray MPPA R . A novel partitioning strategy for reducing the contention on the NoC is proposed. Further, we present an analysis technique dedicated to the proposed partitioning strategy, which considers all architectural features of the COTS NoC. Additionally, it is shown how to configure the parameters for flow-regulation on the NoC, such that the Worst-Case Traversal Time (WCTT) is minimal and buffers never overflow. The benefits of our approach are evaluated based on extensive experiments that show that contention is significantly reduced compared to the unconstrained case, while the proposed analysis outperforms a state-of-the-art analysis for the same platform. An industrial case study shows the tightness of the proposed analysis.

  • 300.
    Becker, Tova
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Etiska och moraliska dilemman vid hantering av personlig information.2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I många tusen år har vad som anses vara etiskt försvarbart diskuterats. Allt fler perspektiv beaktas

    bland annat beroende på den tekniska utvecklingen. På senare tid har utvecklingen av de

    digitala medierna inneburit att personlig information värderas och hanteras på nya sätt. Tekniken

    innebär att nya möjligheter skapas samtidigt som det finns en risk att personlig information

    missbrukas. Detta kan påverka vad som är etiskt försvarbart.

    Detta arbete handlar om hur personlig information hanteras med hjälp av digital teknik. Det

    undersöks om användare av IT är medvetna om att deras personliga information samlas in,

    sprids och används för att skapa en mängd nya individuella tjänster. Det utforskas om denna

    hantering, samt de nya möjligheterna att individualisera tjänster, är något som skapar dilemma.

    Till sist sammanställs rekommendationer som framkommit under studien gällande

    vad enskilda individer kan göra om de vill minska riskerna för att personlig information missbrukas.

    Studien inleds med en litteraturgenomgång vilken belyser hur IT påverkat vårt samhälle samt

    hur personlig information hanteras med den nutida teknikens möjligheter.

    Det beskrivs bland annat:

     Hur företag samlar in användardata i bakgrunden utan att tydligt informera om det

     Att det finns profiler om oss alla

     Att den information vi får är anpassad till oss som individer

     Att personlig information finns lättillgänglig och sökbart för alla bland annat för arbetsgivare

    Etik och moral bör ligga till grund för alla resonemang som avser avgöra vad som är rätt och

    fel. Företagen har riktlinjer för hur de bör handla enligt etiska och moraliska principer. Det

    finns lagstiftning och regelverk som styr men informationshantering utvecklas snabbt och är

    global vilket gör situationen komplex. Tekniken utvecklas ofta snabbare än regelverket.

    Metoden för insamlande av empiri bestod av två delar. Primärdata samlades in via intervjuer

    och sekundärdata söktes via nätet och medier för att få aktuell data som underlag till intervjuerna.

    Intervjuerna genomfördes som semikonstruerade intervjuer där datorer användes som

    hjälpmedel för att exemplifiera data som fanns tillgänglig om respondenten. Den empiri som

    framkom från intervjuerna innehåller en bred beskrivning av ämnesområdet även om urvalsgruppen

    var liten. Insamlad data analyserades genom att notera och sammanställa svaren samt

    söka mönster och samband mellan olika teman i intervjun.

    Slutsatser sammanställdes vilka visar på att det finns oroväckande låg medvetenhet inom ämnesområdet.

    Slutsaterana innehåller också tre dilemman kopplade till hur den tekniska utvecklingen

    hanterar personlig information. Dessa är faktaresistens, kränkning av den personliga

    integriteten och utformning av lagar, avtal och normer. Sist sammanställs rekommendationer

    avsedda för de som vill minska riskerna med hantering av personlig information.

    I slutet diskuteras att det är först när allmänheten börjar reagera som en diskussion kan uppstå.

    Först då kan en eventuell förändring ske där en reglering som behandlar hur individer får beröras

    och hur tekniken får användas växer fram.

3456789 251 - 300 av 2737
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf