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  • 2751.
    Jaradat, Omar
    Mälardalen University, School of Innovation, Design and Engineering. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Contracts-Based Maintenance of Safety Cases2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Safety critical systems are those systems whose failure could result in loss of life, significant property damage, or damage to the environment. System safety is a major property that shall be adequately assured to avoid any severe outcomes in safety critical systems. Safety assurance should provide justified confidence that all potential risks due to system failures are either eliminated or acceptably mitigated. System developers in many domains (e.g., automotive, avionics, railways) should provide convincing arguments regarding the safe performance of their systems to a national or international regulatory authority and obtain approvals before putting the system into service.  Building 'Safety cases' is a proven technique to argue about and communicate systems' safety and it has become a common practice in many safety critical system domains. System developers use safety cases to articulate claims about how systems meet their safety requirements and objectives, collect and document items of evidence, and construct a safety argument to show how the available items of evidence support the claims.

    Safety critical systems are evolutionary and constantly subject to preventive, perfective, corrective or adaptive changes during both the development and operational phases. Changes to any part of those systems can undermine the confidence in safety since changes can refute articulated claims about safety or challenge the supporting evidence on which this confidence relies. Hence, safety cases need to be built as living documents that should always be maintained to justify the safety status of the associated system and evolve as these systems evolve. However, building safety cases are costly since they require a significant amount of time and efforts to define the safety objectives, generate the required evidence and conclude the underlying logic behind the safety case arguments. Safety cases document highly dependent elements such as safety goals, assumptions and evidence. Seemingly minor changes may have a major impact. Changes to a system or its environment can necessitate a costly and painstaking impact analysis for systems and their safety cases. In addition, changes may require system developers to generate completely new items of evidence by repeating the verification activities. Therefore, changes can exacerbate the cost of producing and maintaining safety cases.  

    Safety contracts have been proposed as a means for helping to manage changes. There have been works that discuss the usefulness of contracts for reusability and maintainability. However, there has been little attention on how to derive them and how exactly they can be utilised for system or safety case maintenance.

    The main goal of this thesis is to support the change impact analysis as a key factor to enhance the maintainability of safety cases. We focus on utilising safety contracts to achieve this goal. To address this, we study how safety contracts can support essential factors for any useful change management process, such as (1) identifying the impacted  elements  and  those  that  are  not  impacted, (2) minimising the number of impacted  safety  case  elements, and (3) reducing the  work  needed  to  make  the  impacted  safety  case  elements valid again. The preliminary finding of our study reveals that using safety contracts can be promising to develop techniques and processes to facilitate safety case maintenance. The absence of safety case maintenance guidelines from safety standards and the lack of systematic and methodical maintenance techniques have motivated the work of this thesis. Our work is presented through a set of developed and assessed techniques, where these techniques utilise safety contracts to achieve the overall goal by various contributions. We begin by a framework for evaluation of the impact of change on safety critical systems and safety cases. Through this, we identify and highlight the most sensitive system components to a particular change. We propose new ways to associate system design elements with safety case arguments to enable traceability. How to identify and reduce the propagation of change impact is addressed subsequently.  Our research also uses safety contracts to enable through-life safety assurance by monitoring and detecting any potential mismatch between the design safety assumptions and the actual behaviour of the system during its operational phase. More specifically, we use safety contracts to capture thresholds of selected safety requirements and compare them with the runtime related data (i.e., operational data) to continuously assess and evolve the safety arguments.

    In summary, our proposed techniques pave the way for cost-effective maintenance of safety cases upon preventive, perfective, corrective or adaptive changes in safety critical systems thus helping better decision support for change impact analysis.

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    fulltext
  • 2752.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. University of York, UK.
    Deriving Hierarchical Safety Contracts2015In: Proceedings: 2015 IEEE 21st Pacific Rim International Symposium on Dependable Computing, PRDC 2015, 2015, Vol. jan, p. 119-128Conference paper (Refereed)
    Abstract [en]

    Safety cases need significant amount of time and effort to produce. The required amount of time and effort can be dramatically increased due to system changes as safety cases should be maintained before they can be submitted for certification or re-certification. Anticipating potential changes is useful since it reveals traceable consequences that will eventually reduce the maintenance efforts. However, considering a complete list of anticipated changes is difficult. What can be easier though is to determine the flexibility of system components to changes. Using sensitivity analysis is useful to measure the flexibility of the different system properties to changes. Furthermore, contracts have been proposed as a means for facilitating the change management process due to their ability to record the dependencies among system’s components. In this paper, we extend a technique that uses a sensitivity analysis to derive safety contracts from Fault Tree Analyses (FTA) and uses these contracts to trace changes in the safety argument. The extension aims to enabling the derivation of hierarchical and correlated safety contracts.We motivate the extension through an illustrative example within which we identify limitations of the technique and discuss potential solutions to these limitations. 

  • 2753.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Systematic Maintenance of Safety Cases to Reduce Risk2016In: Lecture Notes in Computer Science, vol. 9923, 2016, p. 17-29Conference paper (Refereed)
    Abstract [en]

    The development of safety cases has become common practice in many safety critical system domains. Safety cases are costly since they need a significant amount of time and efforts to be produced. More- over, safety critical systems are expected to operate for a long period of time and constantly subject to changes during both development and operational phases. Hence, safety cases are built as living documents that should always be maintained to justify the safety status of the associated system and evolve as these system evolve. However, safety cases document highly interdependent elements (e.g., safety goals, evidence, assumptions, etc.) and even seemingly minor changes may have a major impact on them, and thus dramatically increase their cost. In this paper, we identify and discuss some challenges in the maintenance of safety cases. We also present two techniques that utilise safety contracts to facilitate the maintenance of safety cases, we discuss the roles of these techniques in coping with some of the identified maintenance challenges, and we finally discuss potential limitations and suggest some solutions.

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    fulltext
  • 2754.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Using Safety Contracts to Guide the Maintenance of Systems and Safety Cases2017In: European Dependable Computing Conference EDCC'17, 2017, p. 95-102Conference paper (Refereed)
    Abstract [en]

    Changes to safety-critical systems are inevitable and can impact the safety confidence about a system as their effects can refute articulated claims about safety or challenge the supporting evidence on which this confidence relies. In order to maintain the safety confidence under changes, system developers need to re-analyse and re-verify the system to generate new valid items of evidence. Identifying the effects of a particular change is a crucial step in any change management process as it enables system developers to estimate the required maintenance effort and reduce the cost by avoiding wider analyses and verification than strictly necessary. This paper presents a sensitivity analysis-based technique which aims at measuring the ability of a system to contain a change (i.e., robustness) without the need to make a major re-design. The proposed technique exploits the safety margins in the budgeted failure probabilities of events in a probabilistic fault-tree analysis to compensate for unaccounted deficits or changes due to maintenance. The technique utilises safety contracts to provide prescriptive data for what is needed to be revisited and verified to maintain system safety when changes happen. We demonstrate the technique on an aircraft wheel braking system.

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    fulltext
  • 2755.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Using Safety Contracts to Guide the Maintenance of Systems and Safety Cases: An Example2017Report (Other academic)
    Abstract [en]

    Changes to safety critical systems are inevitable and can impact the safety confidence about a system as their effects can refute articulated claims about safety or challenge the supporting evidence on which this confidence relies. In order to maintain the safety confidence due to changes, system developers need to re-analyse and re-verify the system to generate new valid items of evidence. Moreover, identifying the effects of a particular change is a crucial step in any change management process as it enables system developers to estimate the required maintenance effort and reduce the cost by avoiding wider analyses and verification than strictly necessary. This paper presents a sensitivity analysis-based technique which aims at measuring the ability of a system to contain a change (i.e., robustness) without the need to make a major re-design. The technique exploits the safety margins in the assigned failure probabilities to the events of a probabilistic fault-tree analysis to compensate some potential deficits in the overall failure probability budget due to changes. The technique also utilises safety contracts to provide prescriptive data for what is needed to be revisited and verified to maintain system safety when changes happen. We demonstrate the technique on a realistic safety critical system.

    Download full text (pdf)
    fulltext
  • 2756.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Punnekkat, Sasikumar
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Facilitating the Maintenance of Safety Cases2015In: The 3rd International Conference on Reliability, Safety and Hazard - Advances in Reliability, Maintenance and Safety ICRES-ARMS'15, 2015, Vol. F5Conference paper (Refereed)
  • 2757.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Bate, Iain
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Punnekkat, Sasikumar
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Using Sensitivity Analysis to Facilitate The Maintenance of Safety Cases2015In: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) / [ed] Juan Antonio de la Puente, Tullio Vardanega, 2015, Vol. 9111, p. 162-176Conference paper (Refereed)
    Abstract [en]

    A safety case contains safety arguments together with supporting evidence that together should demonstrate that a system is acceptably safe. System changes pose a challenge to the soundness and cogency of the safety case argument. Maintaining safety arguments is a painstaking process because it requires performing a change impact analysis through interdependent elements. Changes are often performed years after the deployment of a system making it harder for safety case developers to know which parts of the argument are affected. Contracts have been proposed as a means for helping to manage changes. There has been significant work that discusses how to represent and to use them but there has been little on how to derive them. In this paper, we propose a sensitivity analysis approach to derive contracts from Fault Tree Analyses and use them to trace changes in the safety argument, thus facilitating easier maintenance of the safety argument. 

  • 2758.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Punnekkat, Sasikumar
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Using Safety Contracts to Verify Design Assumptions During Runtime2018In: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Volume 10873, 2018, p. 3-18Conference paper (Refereed)
    Abstract [en]

    A safety case comprises evidence and argument justifying how each item of evidence supports claims about safety assurance. Supporting claims by untrustworthy or inappropriate evidence can lead to a false assurance regarding the safe performance of a system. Having sufficient confidence in safety evidence is essential to avoid any unanticipated surprise during operational phase. Sometimes, however, it is impractical to wait for high quality evidence from a system’s operational life, where developers have no choice but to rely on evidence with some uncertainty (e.g., using a generic failure rate measure from a handbook to support a claim about the reliability of a component). Runtime monitoring can reveal insightful information, which can help to verify whether the preliminary confidence was over- or underestimated. In this paper, we propose a technique which uses runtime monitoring in a novel way to detect the divergence between the failure rates (which were used in the safety analyses) and the observed failure rates in the operational life. The technique utilises safety contracts to provide prescriptive data for what should be monitored, and what parts of the safety argument should be revisited to maintain system safety when a divergence is detected. We demonstrate the technique in the context of Automated Guided Vehicles (AGVs).

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    fulltext
  • 2759.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Sljivo, Irfan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Habli, Ibrahim
    University of York, UK.
    Hawkins, Richard
    University of York, UK.
    Challenges of Safety Assurance for Industry 4.02017In: European Dependable Computing Conference EDCC'17, Geneva, Switzerland: IEEE Computer Society , 2017, p. 103-106Conference paper (Refereed)
    Abstract [en]

    The Internet-of-Things (IoT) has enabled Industry 4.0 as a new manufacturing paradigm. The envisioned future of Industry 4.0 and Smart Factories is to be highly configurable and composed mainly of the 'things' that are expected to come with some, often partial, assurance guarantees. However, many factories are categorised as safety-critical, e.g. due to the use of heavy machinery or hazardous substances. As such, some of the guarantees provided by the 'things', e.g. related to performance and availability, are deemed as necessary in order to ensure the safety of the manufacturing processes and the resulting products. In this paper, we explore key safety challenges posed by Industry 4.0 and identify the characteristics that its safety assurance should exhibit. We propose a set of safety assurance responsibilities, e.g. system integrators, cloud service providers and `things' suppliers. Finally, we reflect on the desirable modularity of such a safety assurance approach as a basis for cooperative, on-demand and continuous reasoning for Industry 4.0 architectures and services.

  • 2760.
    Jaradat, Omar
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Sljivo, Irfan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Hawkins, Richard
    University of York, York, UK.
    Habli, Ibrahim
    University of York, York, UK.
    Modular Safety Cases for the Assurance of Industry 4.02020In: 28th Safety-Critical Systems Symposium SCSS'20, York, United Kingdom, 2020Conference paper (Refereed)
    Abstract [en]

    The Internet-of-Things (IoT) has enabled Industry 4.0 as a new manufacturing paradigm. The envisioned future of Industry 4.0 and Smart Factories is to be highly configurable and composed mainly of the ‘Things’ that are expected to come with some, often partial, assurance guarantees. However, many factories are categorised as safety-critical, e.g. due to the use of heavy machinery or hazardous substances. As such, some of the guarantees provided by the ‘Things’, e.g. related to performance and availability, are deemed as necessary in order to ensure the safety of the manufacturing processes and the resulting products. In this paper, we explore key safety challenges posed by Industry 4.0 and identify the characteristics that its safety assurance should exhibit. We pro-pose a modular safety assurance model by combination of the different actor responsibilities, e.g. system integrators, cloud service providers and “Things” sup-pliers. Besides the desirable modularity of such a safety assurance approach, our model provides a basis for cooperative, on-demand and continuous reasoning in order to address the reconfigurable nature of Industry 4.0 architectures and ser-vices. We illustrate our approach based on a smart factory use case.

  • 2761.
    Jaradat, Shatha
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Mining of User Profiles in Online Social Networks for Improved Personalized Recommendations2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    We have focused on influencer-based marketing in online social networks as a source of implicit learning about the preferences of social media users. Those users who use social networks on a daily basis are also the online shoppers who are confronted with huge information overload and a wide variety of online products and brands to choose from. The role of digital influencers in promoting products and spreading information to a large scale of followers who engage with the influencers’ posts and interact with them is our key to better understanding of these followers’ tastes and future purchase intentions. Hence, the analysis and the extraction of fine-grained details (which we refer to as user profiling) from digital influencers media content serves in collecting more information about the implicit preferences of their followers. With this knowledge, the chances of offering social media users better personalized services are enhanced. In this thesis, we empower cross-domain recommendations through the development of novel methods and algorithms for improving personalization through the effective mining of user profiles in online social networks. We developed a semantic information extraction framework from social media textual content that is able to capture fine-grained attributes with respect to the defined online shops taxonomy. Results form the aforementioned framework have been applied as input to the approaches we proposed to incorporate extracted textual hints in supporting the visual fine-grained classification of social media images in a dynamic way. Our methods have improved the classification accuracy when compared to state-of-the-art approaches. Moreover, we suggested solutions for incorporating the extracted products’ meta-data in embedding-based personalized recommendation architectures where our strategies improved the recommendations’ quality. In order to speed up the process of preparing large scale social media images datasets for deep learning image analysis, we developed a complete framework for detailed annotation, object localization and semantic segmentation. As our focus is also directed towards the analysis of interactions between social media users, we proposed a neural reinforcement learning approach that is based on estimating the established trust levels between social media users for controlling the amount of recommended updates they get from each other. Moreover, we proposed enhanced topic modelling algorithm for supporting interpretable yet dynamic summarizations of large social media contents.

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    Shatha_Jaradat_Doctoral_Thesis
  • 2762.
    Jaradat, Shatha
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Dokoohaki, Nima
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Matskin, Mihhail
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Outfit2Vec: Incorporating Clothing Hierarchical MetaData into Outfits’ Recommendation2020In: Lecture Notes in Social Networks book series (LNSN): Fashion Recommender Systems / [ed] Springer, Springer: Springer Nature , 2020Chapter in book (Other academic)
  • 2763.
    Javed Awan, Ahsan
    et al.
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Brorsson, Mats
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Vlassov, Vladimir
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Ayguade, Eduard
    Technical University of Catalunya (UPC), Computer Architecture Department.
    Performance Characterization of In-Memory Data Analytics on a Modern Cloud Server2015In: Proceedings - 2015 IEEE 5th International Conference on Big Data and Cloud Computing, BDCloud 2015, IEEE Computer Society, 2015, p. 1-8, article id 7310708Conference paper (Refereed)
    Abstract [en]

    In last decade, data analytics have rapidly progressed from traditional disk-based processing tomodern in-memory processing. However, little effort has been devoted at enhancing performance at micro-architecture level. This paper characterizes the performance of in-memory data analytics using Apache Spark framework. We use a single node NUMA machine and identify the bottlenecks hampering the scalability of workloads. We also quantify the inefficiencies at micro-architecture level for various data analysis workloads. Through empirical evaluation, we show that spark workloads do not scale linearly beyond twelve threads, due to work time inflation and thread level load imbalance. Further, at the micro-architecture level, we observe memory bound latency to be the major cause of work time inflation.

  • 2764.
    Javed, Mohammad
    et al.
    RISE Research Institutes of Sweden.
    Muram, Faiz
    Linnaeus University, Sweden.
    Kanwal, Samina
    National University of Sciences and Technology, Pakistan.
    Ontology-Based Natural Language Processing for Process Compliance Management2021In: Commun. Comput. Info. Sci., Springer Science and Business Media Deutschland GmbH , 2021, p. 309-327Conference paper (Refereed)
    Abstract [en]

    Process compliance with relevant regulations and de-facto standards is a mandatory requirement for certifying critical systems. However, it is often carried out manually, and therefore perceived as complex and labour-intensive. Ontology-based Natural Language Processing (NLP) provides an efficient support for compliance management with critical software system engineering standards. This, however, has not been considered in the literature. Accordingly, the approach presented in this paper focuses on ontology-based NLP for compliance management of software engineering processes with standard documents. In the developed ontology, the process concerns, such as stakeholders, tasks and work products are captured for better interpretation. The rules are created for extracting and structuring information, in which both syntactic features (captured using NLP tasks) and semantic features (captured using ontology) are encoded. During the planning phase, we supported the generation of requirements, process models and compliance mappings in Eclipse Process Framework (EPF) Composer. In the context of reverse compliance, the gaps with standard documents are detected, potential measures for their resolution are provided, and adaptions are made after the process engineer approval. The applicability of the proposed approach is demonstrated by processing ECSS-E-ST-40C, a space software engineering standard, generating models and mappings, as well as reverse compliance management of extended process model. 

  • 2765.
    Javed, Muhammad Atif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering.
    Faiz UL Muram, Faiz UL Muram
    Mälardalen University, School of Innovation, Design and Engineering.
    A framework for the analysis of failure behaviors in component-based model-driven development of dependable systems2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Currently, the development of high-integrity embedded component-based software systems is not supported by well-integrated means allowing for quality evaluation and design support within a development process. Quality, especially dependability, is very important for such systems.

    The CHESS (Composition with Guarantees for High-integrity Embedded Software Components Assembly) project aims at providing a new systems development methodology to capture extra-functional concerns and extend Model Driven Engineering industrial practices and technology approaches to specifically address the architectural structure, the interactions and the behavior of system components while guaranteeing their correctness and the level of service at run time. The CHESS methodology is expected to be supported by a tool-set which consists of a set of plug-ins integrated within the Eclipse IDE.

    In the framework of the CHESS project, this thesis addresses the lack of well integrated means concerning quality evaluation and proposes an integrated framework to evaluate the dependability of high-integrity embedded systems.

    After a survey of various failure behavior analysis techniques, a specific technique, called Failure Propagation and Transformation Calculus (FPTC), is selected and a plug-in, called CHESS-FPTC, is developed within the CHESS tool-set. FPTC technique allows users to calculate the failure behavior of the system from the failure behavior of its building components. Therefore, to fully support FPTC, CHESS-FPTC plug-in allows users to model the failure behavior of the building components, perform the analysis automatically and get the analysis results back into their initial models. A case study about AAL2 Signaling Protocol is presented to illustrate and evaluate the CHESS-FPTC framework.

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    MasterThesis_FPTCAnalysis
  • 2766.
    Javed, Muhammad Atif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Gallina, Barbara
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Get EPF Composer back to the future: A trip from Galileo to Photon after 11 years2018Other (Other academic)
    Abstract [en]

    This talk provides a concrete return of experience about the migration of Eclipse Process Framework (EPF) Composer[i] from Eclipse Galileo 3.5.2 to Eclipse Neon 4.6.3. The migration of EPF Composer was performed[ii] in four phases: compatible versions of required softwares were installed from the Neon software repository and then deprecations in the source code were analyzed and fixed; scheduling conflicts were resolved for the persistence of method elements (i.e., method configurations, method plugins, method content descriptions and processes) in their own folders and XMI files; appearance and height problems were resolved for the combo box which supports users in selecting the currently used method configuration, the blank views were removed from the authoring and browsing perspectives, but also problems with the rich text editor were resolved for enabling users to format and style text; and incompatible bundles were removed from the feature plugins, replacing bundles were added and other missing dependencies for the bundles were resolved for exporting the standalone application. This talk will also present the return of experience of starting a collaboration with the EPF Composer team from IBM in order to submit the migrated code, eventually become a committer of the project, and publish a release of EPF Composer for Eclipse Neon. More about the Eclipse Process Framework: The EPF Composer is an open-source project developed for the process engineers and project managers. It provides support for authoring, tailoring and deploying methods and processes for development organizations and projects. Although this project has attracted considerable attention from researchers and practitioners worldwide, the migration to newer versions of technologies was never performed. In the context of the AMASS project[iii], the migration of EPF Composer was critical for allowing the integration with other tools in the AMASS platform, a large open-source platform that constitutes an ecosystem building on top of several Eclipse and PolarSys projects such as EPF Composer, OpenCert[iv] and CHESS[v]. The migration of EPF Composer has been tested by Vishal Sharnagat (IBM). Barbara Gallina and Muhammad Atif Javed would also like to thank Bruce MacIsaac (IBM), Huascar Espinoza (Tecnalia) and Gaël Blondelle (Eclipse Foundation) for their support in the migration. As future work, we plan to implement the support for CDO model repository[vi]. [i] https://www.eclipse.org/epf/ [ii] https://bugs.eclipse.org/bugs/show_bug.cgi?id=516608 [iii] https://www.amass-ecsel.eu/ [iv] https://www.polarsys.org/proposals/opencert [v] https://www.polarsys.org/projects/polarsys.chess [vi] https://www.eclipse.org/cdo/

  • 2767.
    Javed, Muhammad Atif
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Gallina, Barbara
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Safety-oriented Process Line Engineering via Seamless Integration between EPF Composer and BVR Tool: Variability Management in Process Lines2018In: SPLC '18 Proceeedings of the 22nd International Systems and Software Product Line Conference - Volume 2, 2018, p. 23-28Conference paper (Refereed)
    Abstract [en]

    The integration between process engineering and variability management is required for tailoring of safety-oriented processes with variabilities to individual projects in a similar manner to the product lines. Previous studies have not adequately established the Safety-oriented Process Lines (SoPLs). This paper focuses on the seamless integration between Eclipse Process Framework (EPF) Composer and Base Variability Resolution (BVR) Tool. The former supports the major parts of the OMG’s Software & Systems Process Engineering Metamodel (SPEM) Version 2.0, while the latter is a simplification and enhancement of the OMG’s revised submission of Common Variability Language (CVL). The proposed integration is implemented as Eclipse plugin. It provides support for importing backend folders and files within the method library of EPF Composer, resolving problems with the files for variability management with the BVR Tool, and exporting back the resolved process models to the EPF Composer. The applicability of the implemented plugin is demonstrated by engineering an ECSS-E-ST-40C compliant SoPL for the space projects and applications.

  • 2768.
    Javed, Muhammad Atif
    et al.
    RISE Research Institutes of Sweden, Västerås, Sweden.
    UL Muram, Faiz
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Linnaeus University, Växjö.
    Punnekkat, Sasikumar
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Hansson, Hans
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. RISE Research Institutes of Sweden, Västerås, Sweden.
    Safe and secure platooning of automated guided vehicles in Industry 4.02021In: Journal of systems architecture, ISSN 1383-7621, E-ISSN 1873-6165, Vol. 121, article id 102309Article in journal (Refereed)
    Abstract [en]

    Automated Guided Vehicles (AGVs) are widely used for materials transportation. Operating them in a platooned manner has the potential to improve safety, security and efficiency, control overall traffic flow and reduce resource usage. However, the published studies on platooning focus mainly on the design of technical solutions in the context of automotive domain. In this paper we focus on a largely unexplored theme of platooning in production sites transformed to the Industry 4.0, with the aim of providing safety and security assurances. We present an overall approach for a fault- and threat tolerant platooning for materials transportation in production environments. Our functional use cases include the platoon control for collision avoidance, data acquisition and processing by considering range, and connectivity with fog and cloud levels. To perform the safety and security analyses, the Hazard and Operability (HAZOP) and Threat and Operability (THROP) techniques are used. Based on the results obtained from them, the safety and security requirements are derived for the identification and prevention/mitigation of potential platooning hazards, threats and vulnerabilities. The assurance cases are constructed to show the acceptable safety and security of materials transportation using AGV platooning. We leveraged a simulation-based digital twin for performing the verification and validation as well as fine tuning of the platooning strategy. Simulation data is gathered from digital twin to monitor platoon operations, identify unexpected or incorrect behaviour, evaluate the potential implications, trigger control actions to resolve them, and continuously update assurance cases. The applicability of the AGV platooning is demonstrated in the context of a quarry site.

  • 2769.
    Javeed, Ashir
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Moraes, Ana Luiza Dallora
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Sanmartin Berglund, Johan
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Anderberg, Peter
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    An Intelligent Learning System for Unbiased Prediction of Dementia Based on Autoencoder and Adaboost Ensemble Learning2022In: Life, E-ISSN 2075-1729, Vol. 12, no 7, article id 1097Article in journal (Refereed)
    Abstract [en]

    Dementia is a neurological condition that primarily affects older adults and there is still no cure or therapy available to cure it. The symptoms of dementia can appear as early as 10 years before the beginning of actual diagnosed dementia. Hence, machine learning (ML) researchers have presented several methods for early detection of dementia based on symptoms. However, these techniques suffer from two major flaws. The first issue is the bias of ML models caused by imbalanced classes in the dataset. Past research did not address this issue well and did not take preventative precautions. Different ML models were developed to illustrate this bias. To alleviate the problem of bias, we deployed a synthetic minority oversampling technique (SMOTE) to balance the training process of the proposed ML model. The second issue is the poor classification accuracy of ML models, which leads to a limited clinical significance. To improve dementia prediction accuracy, we proposed an intelligent learning system that is a hybrid of an autoencoder and adaptive boost model. The autoencoder is used to extract relevant features from the feature space and the Adaboost model is deployed for the classification of dementia by using an extracted subset of features. The hyperparameters of the Adaboost model are fine-tuned using a grid search algorithm. Experimental findings reveal that the suggested learning system outperforms eleven similar systems which were proposed in the literature. Furthermore, it was also observed that the proposed learning system improves the strength of the conventional Adaboost model by 9.8% and reduces its time complexity. Lastly, the proposed learning system achieved classification accuracy of 90.23%, sensitivity of 98.00% and specificity of 96.65%.

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  • 2770.
    Javeed, Ashir
    et al.
    Aging Research Center, Karolinska Institutet, Stockholm, Sweden ; Department of Health, Blekinge Institute of Technology, Karlskrona, Sweden.
    Saleem, Muhammad Asim
    Center of Excellence in Artificial Intelligence, Machine Learning and Smart Grid Technology, Department of Electrical Engineering, Chulalongkorn University, Bangkok, Thailand.
    Dallora, Ana Luiza
    Department of Health, Blekinge Institute of Technology, Karlskrona, Sweden.
    Ali, Liaqat
    Department of Electrical Engineering, University of Science and Technology Bannu, Pakistan.
    Sanmartin Berglund, Johan
    Department of Health, Blekinge Institute of Technology, Karlskrona, Sweden.
    Anderberg, Peter
    University of Skövde, School of Health Sciences. University of Skövde, Digital Health Research (DHEAR). Department of Health, Blekinge Institute of Technology, Karlskrona, Sweden.
    Decision Support System for Predicting Mortality in Cardiac Patients Based on Machine Learning2023In: Applied Sciences, E-ISSN 2076-3417, Vol. 13, no 8, article id 5188Article in journal (Refereed)
    Abstract [en]

    Researchers have proposed several automated diagnostic systems based on machine learning and data mining techniques to predict heart failure. However, researchers have not paid close attention to predicting cardiac patient mortality. We developed a clinical decision support system for predicting mortality in cardiac patients to address this problem. The dataset collected for the experimental purposes of the proposed model consisted of 55 features with a total of 368 samples. We found that the classes in the dataset were highly imbalanced. To avoid the problem of bias in the machine learning model, we used the synthetic minority oversampling technique (SMOTE). After balancing the classes in the dataset, the newly proposed system employed a (Formula presented.) statistical model to rank the features from the dataset. The highest-ranked features were fed into an optimized random forest (RF) model for classification. The hyperparameters of the RF classifier were optimized using a grid search algorithm. The performance of the newly proposed model ((Formula presented.) _RF) was validated using several evaluation measures, including accuracy, sensitivity, specificity, F1 score, and a receiver operating characteristic (ROC) curve. With only 10 features from the dataset, the proposed model (Formula presented.) _RF achieved the highest accuracy of 94.59%. The proposed model (Formula presented.) _RF improved the performance of the standard RF model by 5.5%. Moreover, the proposed model (Formula presented.) _RF was compared with other state-of-the-art machine learning models. The experimental results show that the newly proposed decision support system outperforms the other machine learning systems using the same feature selection module ((Formula presented.)). 

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  • 2771.
    Jayaram, M.A.
    et al.
    Siddaganga Institute of Technology.
    Fleyeh, Hasan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Convex Hulls in Image Processing: A Scoping Review2016In: American Journal of Intelligent Systems, ISSN 2165-8978, E-ISSN 2165-8994, Vol. 6, no 2, p. 48-58Article in journal (Refereed)
    Abstract [en]

    The demands of image processing related systems are robustness, high recognition rates, capability to handle incomplete digital information, and magnanimous flexibility in capturing shape of an object in an image. It is exactly here that, the role of convex hulls comes to play. The objective of this paper is twofold. First, we summarize the state of the art in computational convex hull development for researchers interested in using convex hull image processing to build their intuition, or generate nontrivial models. Secondly, we present several applications involving convex hulls in image processing related tasks. By this, we have striven to show researchers the rich and varied set of applications they can contribute to. This paper also makes a humble effort to enthuse prospective researchers in this area. We hope that the resulting awareness will result in new advances for specific image recognition applications.

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  • 2772.
    Jayaram, M.A.
    et al.
    Siddaganga Institute of Technology, Tumakuru, Karnataka, India.
    Fleyeh, Hasan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Whither Edge Computing? – A Futuristic Review2018In: International Journal of Applied Research on Information Technology and Computing, ISSN 0975-8070, Vol. 9, no 2, p. 180-188Article in journal (Refereed)
    Abstract [en]

    It is a well-known fact that the current day Internet is increasingly becoming laden with content that is bandwidth demanding due to ever-increasing number of things getting attached on a day-in and day-out basis. Hand-in-hand, mobile networks and data networks are converging into cloud computing bandwagon. Edge computing as a promising feature has already made inroads to face future requirements and to address exponential demands from cloud. This feature is all about inserting computing power and storage in the vicinity of the network edge. It is asserted that this scheme of operation brings down the data transport time, quick response times and increased availability. Edge computing brings bandwidthintensive content and latency-sensitive applications closer to the user or data source. In this paper, we explain the drivers of edge computing and have delved on various types of edge computing currently available and going to throng in near future. This paper is intended to draw a comprehensive picture of what is happening in edge currently and what would happen in the near foreseeable future.

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  • 2773.
    Jayaraman, Vijay
    Halmstad University, School of Information Technology.
    Enhancing failure prediction from timeseries histogram data: through fine-tuned lower-dimensional representations2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Histogram data are widely used for compressing high-frequency time-series signals due to their ability to capture distributional informa-tion. However, this compression comes at the cost of increased di-mensionality and loss of contextual details from the original features.This study addresses the challenge of effectively capturing changesin distributions over time and their contribution to failure prediction.Specifically, we focus on the task of predicting Time to Event (TTE) forturbocharger failures.In this thesis, we propose a novel approach to improve failure pre-diction by fine-tuning lower-dimensional representations of bi-variatehistograms. The goal is to optimize these representations in a waythat enhances their ability to predict component failure. Moreover, wecompare the performance of our learned representations with hand-crafted histogram features to assess the efficacy of both approaches.We evaluate the different representations using the Weibull Time ToEvent - Recurrent Neural Network (WTTE-RNN) framework, which isa popular choice for TTE prediction tasks. By conducting extensive ex-periments, we demonstrate that the fine-tuning approach yields supe-rior results compared to general lower-dimensional learned features.Notably, our approach achieves performance levels close to state-of-the-art results.This research contributes to the understanding of effective failureprediction from time series histogram data. The findings highlightthe significance of fine-tuning lower-dimensional representations forimproving predictive capabilities in real-world applications. The in-sights gained from this study can potentially impact various indus-tries, where failure prediction is crucial for proactive maintenanceand reliability enhancement.

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  • 2774.
    Jean Paul, Bambanza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    iSEE:A Semantic Sensors Selection System for Healthcare2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The massive use of Internet-based connectivity of devices such as smartphones and sensors has led to the emergence of Internet of Things(IoT). Healthcare is one of the areas that IoT-based applications deployment is becoming more successful. However, the deployment of IoT in healthcare faces one major challenge, the selection of IoT devices by stakeholders (for example, patients, caregivers, health professionals and other government agencies) given an amount of available IoT devices based on a disease(for ex-ample, Asthma) or various healthcare scenarios (for example, disease management, prevention and rehabilitation). Since healthcare stakeholders currently do not have enough knowledge about IoT, the IoT devices selection process has to proceed in a way that it allows users to have more detailed information about IoT devices for example, Quality of Service (QoS) parameters, cost, availability(manufacturer), device placement and associated disease. To address this challenge, this thesis work proposes, develops and validates a novel Semantic sEnsor sElection system(iSEE) for healthcare. This thesis also develops iSEE system prototype and Smart Healthcare Ontology(SHO). A Java application is built to allow users for querying our developed SHO in an efficient way.The iSEE system is evaluated based on query response time and the result-set for the queries. Further, we evaluate SHO using Competency Questions(CQs). The conducted evaluations show that our iSEE system can be used efficiently to support stakeholders within the healthcare domain.

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  • 2775.
    Jena, Kalyan Kumar
    et al.
    Department of Computer Science and Engineering, Parala Maharaja Engineering College (Govt.), Odisha, Berhampur, India.
    Bhoi, Sourav Kumar
    Department of Computer Science and Engineering, Parala Maharaja Engineering College (Govt.), Odisha, Berhampur, India.
    Mohapatra, Debasis
    Department of Computer Science and Engineering, Parala Maharaja Engineering College (Govt.), Odisha, Berhampur, India.
    Mallick, Chittaranjan
    Department of Basic Science (Mathematics), Parala Maharaja Engineering College (Govt.), Odisha, Berhampur, India.
    Sahoo, Kshira Sagar
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Department of Computer Science and Engineering, SRM University, AP, Amaravati, India.
    Nayyar, Anand
    Graduate School, Duy Tan University, Da Nang, Vietnam.
    A fuzzy rule based machine intelligence model for cherry red spot disease detection of human eyes in IoMT2023In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 29, no 1, p. 247-265Article in journal (Refereed)
    Abstract [en]

    Internet of medical things (IoMT) plays an important role nowadays to support healthcare system. The hospital equipment’s called as medical things are now connected to the cloud for getting many useful services. The data generated from the equipments are sent to the cloud for getting the desired service. In current scenario, most hospitals collect many images using equipments, but these equipments have less computational capability to process the huge generated data. In this work, one such equipment is considered which can take the human eye images and send the images to the cloud for detection of cherry red spot (CRS). CRS disease in eyes is considered as one of the very dangerous disease. The early diagnosis of CRS disease needs to be focused in order to avoid any adverse effect on human body. In this paper, a machine intelligence based model is proposed to detect the CRS disease areas in the human eyes by analyzing several CRS disease images using IoMT. The proposed approach is mainly focused on fuzzy rule-based mechanism to carry out the identification of such affected area in the eyes in cloud layer. From the results, it is observed that the CRS disease areas in the eyes are detected well with better detection accuracy and lower detection error than k-means algorithm. This approach will help the doctors to track the exact position of the affected areas in the eye for its diagnosis. The simulation is performed using socket programming written in Python 3 where a cloud server and a client device are created and images are sent from the client device to the server, and afterwards the detection of CRS is performed at the server using MATLAB R2015b. The proposed method is able to provide better performance in terms of detection accuracy, detection error and processing time as 94.67%, 5.33% and 1.1481% units respectively on an average case scenario.

  • 2776.
    Jensen, Max
    et al.
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Djärv, Mattias
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    6LoWPAN over BLE energy savings2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet of Things is considered to have the possibility to be a new revolution with the means to impact the future in a big way. The computers that would form this "Inter-net of Things" (IoT) would need to depend on being battery-powered and in a small form factor. To enable this, an energy-efficient communication technology is required. Because of this it, 6LoWPAN was studied and implemented to test the energy consumption versus a more traditional wireless technique. It was determined that 6LoWPAN is a type of network and that it will save energy. 6LoWPAN over Bluetooth Low Energy (BLE) has been measured to use approximately 50% less energy than normal WiFi (802.11n) to send the same data.

  • 2777.
    Jeong, Yongkuk
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering, Advanced Maintenance and Production Logistics.
    Wiktorsson, Magnus
    KTH, School of Industrial Engineering and Management (ITM), Production engineering, Advanced Maintenance and Production Logistics.
    Park, Donggyun
    KTH.
    Gans, Jesper
    KTH.
    Svensson, Linda
    Scania AB, Södertälje, Sweden.
    Data Preparation for AI-Assisted Video Analysis in Manual Assembly Task: A Step Towards Industry 5.02023In: Advances in Production Management Systems. Production Management Systems for Responsible Manufacturing, Service, and Logistics Futures - IFIP WG 5.7 International Conference, APMS 2023, Proceedings, Springer Nature , 2023, p. 619-631Conference paper (Refereed)
    Abstract [en]

    Manual assembly task analysis is essential for optimizing work instructions, improving tasks, and scheduling assembly lines in the context of Industry 5.0’s emphasis on human-centric, sustainable, and resilient manufacturing processes. The current paper outlines a comprehensive approach for data preparation for AI-assisted video analysis, aiming to simplify manual assembly task analysis, alleviate the workload of assembly operators and time setting experts, and advance Industry 5.0 principles. The paper focuses on setting up processes for recording videos of assembly tasks and converting the operator movements into skeleton models for subsequent analysis. Landmark points extracted from these models provide a numerical basis for task analysis. This data preparation process prepares the ground for future machine learning-based time setting prediction, considering companies’ unique time settings. The paper also addresses the ethical implications of video recording and data anonymization. Future work will delve into machine learning applications for time setting prediction and task-to-landmark correlations.

  • 2778.
    Jeppson, Laika
    et al.
    University West, Department of Engineering Science.
    Wiberg, Remilia
    University West, Department of Engineering Science.
    Investigating Cloudflare’s Communication Security2022Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Cloudflare is currently a popular CDN, or Content Delivery Network, which also provides some security features to make websites faster and more secure. CDNs are a type of service offered by Cloudflare, which involves a geographically dispersed network of proxy servers and data centers. 

    These security features have been tested to ensure that what Cloudflare claims is true - is a website behind Cloudflare immediately more secure, or is there something you need to know before using their services? 

    This is an analysis primarily of Cloudflare's SSL/TLS security and how the configuration looks and works, and an investigative part which is supported by Cloudflare's own documentation and other articles or essays on the same topic.

    Conclusions that can be drawn from what has been done are that Cloudflare is a relatively secure service but may have weaknesses and vulnerabilities from certain aspects that could affect unfamiliar users.

  • 2779.
    Jernberg, Jimmy
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Vlassov, Vladimir
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Ghodsi, Ali
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    Haridi, Seif
    KTH, School of Information and Communication Technology (ICT), Electronic, Computer and Software Systems, ECS.
    DOH: A Content Delivery Peer-to-Peer Network2006In: Euro-Par 2006 Parallel Processing: 12th International Euro-Par Conference, Dresden, Germany, August 28 – September 1, 2006. Proceedings / [ed] Wolfgang E. Nagel, Wolfgang V. Walter and Wolfgang Lehner, 2006, Vol. 4128, p. 1026-1039Conference paper (Refereed)
    Abstract [en]

    Many SMEs and non-profit organizations suffer when their Web servers become unavailable due to flash crowd effects when their web site becomes popular. One of the solutions to the flash-crowd problem is to place the web site on a scalable CDN (Content Delivery Network) that replicates the content and distributes the load in order to improve its response time. In this paper, we present our approach to building a scalable Web Hosting environment as a CDN on top of a structured peer-to-peer system of collaborative web-servers integrated to share the load and to improve the overall system performance, scalability, availability and robustness. Unlike cluster-based solutions, it can run on heterogeneous hardware, over geographically dispersed areas. To validate and evaluate our approach, we have developed a system prototype called DOH (DKS Organized Hosting) that is a CDN implemented on top of the DKS (Distributed K-nary Search) structured P2P system with DHT (Distributed Hash table) functionality [9]. The prototype is implemented in Java, using the DKS middleware, the Jetty web-server, and a modified JavaFTP server. The proposed design of CDN has been evaluated by simulation and by evaluation experiments on the prototype.

  • 2780.
    Jernberg, Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Metoder för att sända meddelanden från QT Systems fastighetssystem till smarta telefoner2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    For a long time companies have been able to reach out to customers by traditionally methods such as SMS or e-mail. The huge rise of popularity in smartphones and social media now makes information more important than ever. With this there are newer ways for companies to communicate with their customers such as push-notifications by native apps and browsers or by social media.

    This project was ordered by QT Systems with the purpose to give the company a better view of their possibilities when it comes to reaching out with information to their customers. The goal with the project was to find the best method for allowing QT Systems' real estate system to notify their users of certain events and to show that this method can be implemented in this system.

    During the course of this project it was decided that push-notifications by a native app would be the best solution. A ”proof-of-concept” which shows that this method can be implemented in QT Systems' real estate system and that it can be used for at least Android and iOS smartphones was also done.

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  • 2781.
    Jernlås, Johan
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Evaluation of virtual servers for use incomputer science education: Utvardering av virtuella servrar f ör användning inom undervisning i datateknik2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Virtual servers are being increasingly utilized in higher education forclient computers, this thesis investigates if virtualization could also bebeneficial for servers. By providing three general models (the first beingthe current situation and the two latter leveraging virtualization) andevaluating each, a broad sense of the applicability, possibilities andremaining problems of introducing server virtualization is provided.For one specific course, TDDD27 - Advanced web programming, amore concrete analysis is done and specific recommendations are pro-vided.The conclusion is that there are still more work to be done, butboth of the proposed models are possible and suitable for some courses.Their introduction should have several positive effects, for instancefairer courses and more focus on the subject at hand.

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    Evaluation of virtual servers
  • 2782.
    Jerčić, Petar
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    The Effects of Emotions and Their Regulation on Decision-making Performance in Affective Serious Games2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Emotions are thought to be one of the key factors that critically influence human decision-making. Emotion-regulation can help to mitigate emotion-related decision biases and eventually lead to a better decision performance. Serious games emerged as a new angle introducing technological methods to practicing emotion-regulation, where meaningful biofeedback information communicates player's affective states to a series of informed gameplay choices. These findings motivate the notion that in the decision context of serious games, one would benefit from awareness and regulation of such emerging emotions.

    This thesis explores the design and evaluation methods for creating serious games where emotion-regulation can be practiced using physiological biofeedback measures. Furthermore, it investigates emotions and the effect of emotion-regulation on decision performance in serious games. Using the psychophysiological methods in the design of such games, emotions and their underlying neural mechanism have been explored.

    The results showed the benefits of practicing emotion-regulation in serious games, where decision-making performance was increased for the individuals who down-regulated high levels of arousal while having an experience of positive valence. Moreover, it increased also for the individuals who received the necessary biofeedback information. The results also suggested that emotion-regulation strategies (i.e., cognitive reappraisal) are highly dependent on the serious game context. Therefore, the reappraisal strategy was shown to benefit the decision-making tasks investigated in this thesis. The results further suggested that using psychophysiological methods in emotionally arousing serious games, the interplay between sympathetic and parasympathetic pathways could be mapped through the underlying emotions which activate those two pathways. Following this conjecture, the results identified the optimal arousal level for increased performance of an individual on a decision-making task, by carefully balancing the activation of those two pathways. The investigations also validated these findings in the collaborative serious game context, where the robot collaborators were found to elicit diverse affect in their human partners, influencing performance on a decision-making task. Furthermore, the evidence suggested that arousal is equally or more important than valence for the decision-making performance, but once optimal arousal has been reached, a further increase in performance may be achieved by regulating valence. Furthermore, the results showed that serious games designed in this thesis elicited high physiological arousal and positive valence. This makes them suitable as research platforms for the investigation of how these emotions influence the activation of sympathetic and parasympathetic pathways and influence performance on a decision-making task.

    Taking these findings into consideration, the serious games designed in this thesis allowed for the training of cognitive reappraisal emotion-regulation strategy on the decision-making tasks. This thesis suggests that using evaluated design and development methods, it is possible to design and develop serious games that provide a helpful environment where individuals could practice emotion-regulation through raising awareness of emotions, and subsequently improve their decision-making performance.

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  • 2783.
    Jerčić, Petar
    et al.
    Blekinge Institute of Technology, School of Computing.
    Astor, Philipp J
    FZI Forschungszentrum Informatik, DEU.
    Adam, Marc
    Karlsruhe Institute of Technology, DEU.
    Hilborn, Olle
    Blekinge Institute of Technology, School of Computing.
    Schaff, Kristina
    FZI Forschungszentrum Informatik, DEU.
    Lindley, Craig
    Blekinge Institute of Technology, School of Computing.
    Sennersten, Charlotte
    Blekinge Institute of Technology, School of Computing.
    Eriksson, Jeanette
    Blekinge Institute of Technology, School of Computing.
    A Serious Game using Physiological Interfaces for Emotion Regulation Training in the context of Financial Decision-Making2012In: ECIS 2012 - Proceedings of the 20th European Conference on Information Systems, AIS Electronic Library (AISeL) , 2012, p. 1-14Conference paper (Refereed)
    Abstract [en]

    Research on financial decision-making shows that traders and investors with high emotion regulation capabilities perform better in trading. But how can the others learn to regulate their emotions? ‘Learning by doing’ sounds like a straightforward approach. But how can one perform ‘learning by doing’ when there is no feedback? This problem particularly applies to learning emotion regulation, because learners can get practically no feedback on their level of emotion regulation. Our research aims at providing a learning environment that can help decision-makers to improve their emotion regulation. The approach is based on a serious game with real-time biofeedback. The game is settled in a financial context and the decision scenario is directly linked to the individual biofeedback of the learner’s heart rate data. More specifically, depending on the learner’s ability to regulate emotions, the decision scenario of the game continuously adjusts and thereby becomes more (or less) difficult. The learner wears an electrocardiogram sensor that transfers the data via Bluetooth to the game. The game itself is evaluated at several levels.

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  • 2784.
    Jerčić, Petar
    et al.
    Blekinge Institute of Technology, School of Computing.
    Cederholm, Henrik
    Blekinge Institute of Technology, School of Computing.
    The Future of Brain-Computer Interface for Games and Interaction Design2010Report (Other academic)
  • 2785.
    Jerčić, Petar
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Sundstedt, Veronica
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Practicing Emotion-Regulation Through Biofeedback on the Decision-Making Performance in the Context of Serious Games: a Systematic Review2019In: Entertainment Computing, ISSN 1875-9521, E-ISSN 1875-953X, Vol. 29, p. 75-86Article in journal (Refereed)
    Abstract [en]

    Evidence shows that emotions critically influence human decision-making. Therefore, emotion-regulation using biofeedback has been extensively investigated. Nevertheless, serious games have emerged as a valuable tool for such investigations set in the decision-making context. This review sets out to investigate the scientific evidence regarding the effects of practicing emotion-regulation through biofeedback on the decision-making performance in the context of serious games. A systematic search of five electronic databases (Scopus, Web of Science, IEEE, PubMed Central, Science Direct), followed by the author and snowballing investigation, was conducted from a publication's year of inception to October 2018. The search identified 16 randomized controlled experiment/quasi-experiment studies that quantitatively assessed the performance on decision-making tasks in serious games, involving students, military, and brain-injured participants. It was found that the participants who raised awareness of emotions and increased the skill of emotion-regulation were able to successfully regulate their arousal, which resulted in better decision performance, reaction time, and attention scores on the decision-making tasks. It is suggested that serious games provide an effective platform validated through the evaluative and playtesting studies, that supports the acquisition of the emotion-regulation skill through the direct (visual) and indirect (gameplay) biofeedback presentation on decision-making tasks.

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  • 2786.
    Jerčić, Petar
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Wen, Wei
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics. Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Hagelbäck, Johan
    Linnéuniversitetet, SWE.
    Sundstedt, Veronica
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    The Effect of Emotions and Social Behavior on Performance in a Collaborative Serious Game Between Humans and Autonomous Robots2018In: International Journal of Social Robotics, ISSN 1875-4791, E-ISSN 1875-4805, Vol. 10, no 1, p. 115-129Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to investigate performance in a collaborative human–robot interaction on a shared serious game task. Furthermore, the effect of elicited emotions and perceived social behavior categories on players’ performance will be investigated. The participants collaboratively played a turn-taking version of the Tower of Hanoi serious game, together with the human and robot collaborators. The elicited emotions were analyzed in regards to the arousal and valence variables, computed from the Geneva Emotion Wheel questionnaire. Moreover, the perceived social behavior categories were obtained from analyzing and grouping replies to the Interactive Experiences and Trust and Respect questionnaires. It was found that the results did not show a statistically significant difference in participants’ performance between the human or robot collaborators. Moreover, all of the collaborators elicited similar emotions, where the human collaborator was perceived as more credible and socially present than the robot one. It is suggested that using robot collaborators might be as efficient as using human ones, in the context of serious game collaborative tasks.

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  • 2787.
    Jesper, Lindberg
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Hybridapplikationer för desktopmiljön: Utvärdering av ramverk2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is about the frameworks that are available for developing hybrid applicationsfor the desktop environment. The two main frameworks are compared through aqualitative analysis and implementation of the test application. The results show thatone framework is significantly better suited for the development of hybrid applicationsas of right now.

  • 2788.
    Jessen, Jakob
    et al.
    Malmö University, Faculty of Technology and Society (TS).
    Hyldgaard, Albin
    PWA vs Native: Analysering av användarupplevelsen2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studies syfte är att ställa Progressive web apps mot native applikationer för att jämföra upplevd user experience.

    Progressive Web App är en teknik som börjar bli allt mer vanlig för företag att implementera. Författarna utforskar ämnet mer riktat åt användarens upplevelse för att se vilka faktorer som kan spela in i valet mellan Progressive web app och native.

    Författarna har använt sig flertalet olika metoder för att studera om det finns någon skillnad i användarupplevelsen mellan en Progressive web app och en native applikation. Dessa metoder innefattar exempelvis think aloud protocol, system usability scale och Nielsens heuristics. Sett till teorin bakom en Progressive web app så säger den att det ska vara möjligt att kunna replikera en native applikation i form av funktionalitet men vi har i vår studie valt att titta utanför funktionalitet och lagt mer fokus på användarupplevelsen.

    Studien påvisar att de finns skillnader i upplevd användbarhet mellan PWA och native i vissa avseenden. Men de går inte att helt fastställa om dessa beror på utomstående faktorer.

    Trots att studien inte påvisade ett klart svar så ger de en grund till vidare forskning för hur man kan välja mellan de olika teknikerna framåt.

  • 2789.
    Jeusfeld, Manfred A.
    Tilburg University, Department of Information Management, The Netherlands.
    Metamodeling and method engineering with ConceptBase2009In: Metamodeling for Method Engineering / [ed] Manfred A. Jeusfeld; Matthias Jarke; John Mylopoulos, Cambridge, Massachusetts, USA: MIT Press, 2009, p. 89-168Chapter in book (Other academic)
    Abstract [en]

    This chapter provides a practical guide on how to use the meta datarepository ConceptBase to design information modeling methods by using meta-modeling. After motivating the abstraction principles behind meta-modeling, thelanguage Telos as realized in ConceptBase is presented. First, a standard factualrepresentation of statements at any IRDS abstraction level is defined. Then, thefoundation of Telos as a logical theory is elaborated yielding simple fixpointsemantics. The principles for object naming, instantiation, attribution, andspecialization are reflected by roughly 30 logical axioms. After the languageaxiomatization, user-defined rules, constraints and queries are introduced. The firstpart is concluded by a description of active rules that allows the specification ofreactions of ConceptBase to external events. The second part applies the languagefeatures of the first part to a full-fledged information modeling method: The Yourdanmethod for Modern Structured Analysis. The notations of the Yourdan method aredesigned along the IRDS framework. Intra-notational and inter-notational constraintsare mapped to queries. The development life cycle is encoded as a software processmodel closely related to the modeling notations. Finally, aspects managing themodeling activities are addressed by metric definitions.

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  • 2790.
    Jeusfeld, Manfred
    et al.
    University of Skövde, School of Humanities and Informatics.
    Delcambre, Lois
    Ling, Tok Wang
    Preface: Special Section featuring extended papers from the 30th International Conference on Conceptual Modeling (ER-2011)2013In: Data & Knowledge Engineering, ISSN 0169-023X, E-ISSN 1872-6933, Vol. 87, p. 259-Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    The 30th International Conference on Conceptual Modeling (ER-2011) highlighted the strong and persistent interest in research on conceptual modeling for developing information systems. Topics included data modeling theory, goal modeling, socio-technical factors, requirements engineering, process modeling, and ontologies.

  • 2791.
    Jevinger, Åse
    et al.
    Malmö University, Faculty of Technology and Society (TS), Department of Computer Science and Media Technology (DVMT). Malmö University, Internet of Things and People (IOTAP).
    Olsson, Carl Magnus
    Malmö University, Faculty of Technology and Society (TS), Department of Computer Science and Media Technology (DVMT). Malmö University, Internet of Things and People (IOTAP).
    Introducing an Intelligent Goods Service Framework2021In: Logistics, ISSN 2305-6290, Vol. 5, no 3, article id 54Article in journal (Refereed)
    Abstract [en]

    With the increasing diffusion of Internet of Things (IoT) technologies, the transportation of goods sector is in a position to adopt novel intelligent services that cut across the otherwise highly fragmented and heterogeneous market, which today consists of a myriad of actors. Legacy systems that rely upon direct integration between all actors involved in the transportation ecosystem face considerable challenges for information sharing. Meanwhile, IoT based services, which are designed as devices that follow goods and communicate directly to cloud-based backend systems, may provide services that previously were not available. For the purposes of this paper, we present a theoretical framework for classification of such intelligent goods systems based on a literature study. The framework, labelled as the Intelligent Goods Service (IGS) framework, aims at increasing the understanding of the actors, agents, and services involved in an intelligent goods system, and to facilitate system comparisons and the development of new innovative solutions. As an illustration of how the IGS framework can be used and contribute to research in this area, we provide an example from a direct industry-academia collaboration.

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  • 2792.
    Jhunjhunwala, Pranay
    et al.
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Blech, Jan Olaf
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Zoitl, Alois
    Johannes Kepler University Linz, Linz, Austria.
    Atmojo, Udayanto Dwi
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Vyatkin, Valeriy
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    A Design Pattern for Monitoring Adapter Connections in IEC 614992021In: Proceedings: 2021 22nd IEEE International Conference on Industrial Technology (ICIT), IEEE, 2021, p. 967-972Conference paper (Refereed)
    Abstract [en]

    Today's software developments are frequently structured into different components with well defined interfaces. IEC 61499 comes with well defined interface mechanisms such as adapters that group data and event exchange between different subsystems. Compliance with interface specifications can be monitored at run-time. In this paper we present a design pattern to monitor adapters thereby observing whether communication specifications are fulfilled. We present an example demonstrating monitoring of a handshaking mechanism used between control application components.

  • 2793.
    Jhunjhunwala, Pranay
    et al.
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Zoitl, Alois
    Johannes Kepler University Linz, Linz, Austria.
    Dwi Atmojo, Udayanto
    Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Vyatkin, Valeriy
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland.
    Monitoring design pattern for distributed automation systems in IEC 61499 and its formal modelling2022In: 2022 IEEE 31st International Symposium on Industrial Electronics (ISIE), IEEE, 2022, p. 220-225Conference paper (Refereed)
    Abstract [en]

    This paper addresses the challenge of achieving reliable and predictable operation of flexible and modular pro-duction systems with distributed control and potentially wireless communication. Such systems are envisaged as common in the future Industry 4.0 production facilities. A software design pattern is proposed to implement online monitoring of requirements. The IEC 61499 architecture is selected as the implementation platform and its benefits are essentially used by utilisation of the adapter interface mechanism. The paper also outlines a pathway to designing and verifying the monitors based on formal methods.

  • 2794.
    Ji, Wei
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Li, Y.
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    A task-oriented cyber-physical system in manufacturing2018In: Proceedings of International Conference on Computers and Industrial Engineering, CIE, Curran Associates Inc. , 2018Conference paper (Refereed)
    Abstract [en]

    Towards automatic operations on a shop floor, this paper proposes a task-oriented cyber-physical system (CPS) concept, called holonic CPS. Within the context, operation processes are separated and modelled independently, and machines are also divided into hardware and basic controllers. The elementary distributed entities from operation processes and machines are represented by holons including “Cyber” and “Physical” parts. A holon is designed in hierarchical structure involving agent, FB, controller and hardware from top to bottom, and a holarchy, a holonic network including relevant holons, is able to represent a task or a function on the shop floor. To show how the proposed holonic CPS works, a robotic application is designed, in which both assembly tasks and machining (grinding and polishing) tasks can be performed. Where a set of relevant holons and holarchies are presented, which provide a “library” as the basis to represent an ordered task. A microkernel architecture is designed to implement the holonic CPS. A major benefit under the holonic CPS allows the partial manufacturing operation to be transferred into computing issues.

  • 2795.
    Jiang, Ke
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Security-Driven Design of Real-Time Embedded Systems2015Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Real-time embedded systems (RTESs) have been widely used in modern society. And it is also very common to find them in safety and security critical applications, such as transportation and medical equipment. There are, usually, several constraints imposed on a RTES, for example, timing, resource, energy, and performance, which must be satisfied simultaneously. This makes the design of such systems a difficult problem.

    More recently, the security of RTESs emerges as a major design concern, as more and more attacks have been reported. However, RTES security, as a parameter to be considered during the design process, has been overlooked in the past. This thesis approaches the design of secure RTESs focusing on aspects that are particularly important in the context of RTES, such as communication confidentiality and side-channel attack resistance.

    Several techniques are presented in this thesis for designing secure RTESs, including hardware/software co-design techniques for communication confidentiality on distributed platforms, a global framework for secure multi-mode real-time systems, and a scheduling policy for thwarting differential power analysis attacks. 

    All the proposed solutions have been extensively evaluated in a large amount of experiments, including two real-life case studies, which demonstrate the efficiency of the presented techniques.

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  • 2796.
    Jiang, Lili
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Torra, Vicenç
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Data protection and multi-database data-driven models2023In: Future Internet, E-ISSN 1999-5903, Vol. 15, no 3, article id 93Article in journal (Refereed)
    Abstract [en]

    Anonymization and data masking have effects on data-driven models. Different anonymization methods have been developed to provide a good trade-off between privacy guarantees and data utility. Nevertheless, the effects of data protection (e.g., data microaggregation and noise addition) on data integration and on data-driven models (e.g., machine learning models) built from these data are not known. In this paper, we study how data protection affects data integration, and the corresponding effects on the results of machine learning models built from the outcome of the data integration process. The experimental results show that the levels of protection that prevent proper database integration do not affect machine learning models that learn from the integrated database to the same degree. Concretely, our preliminary analysis and experiments show that data protection techniques have a lower level of impact on data integration than on machine learning models.

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  • 2797. Jiang, M.
    et al.
    Rahmani, Amir
    KTH, School of Information and Communication Technology (ICT), Industrial and Medical Electronics. University of Turku, Finland.
    Westerlund, T.
    Liljeberg, P.
    Tenhunen, Hannu
    KTH, School of Information and Communication Technology (ICT), Industrial and Medical Electronics. University of Turku, Finland.
    Facial expression recognition with sEMG method2015In: Proceedings - 15th IEEE International Conference on Computer and Information Technology, CIT 2015, 14th IEEE International Conference on Ubiquitous Computing and Communications, IUCC 2015, 13th IEEE International Conference on Dependable, Autonomic and Secure Computing, DASC 2015 and 13th IEEE International Conference on Pervasive Intelligence and Computing, PICom 2015, Institute of Electrical and Electronics Engineers (IEEE), 2015, p. 981-988Conference paper (Refereed)
    Abstract [en]

    Facial expression recognition has broad application prospects in the fields of psychological study, nursing care, Human Computer Interaction as well as affective computing. The method with surface Electromyogram (sEMG), which is one of vital bio-signals, has its superiority in several aspects such as high temporal resolution and data processing efficiency over other methods. Researches regarding EMG signal to study emotional expression have started since the second half of last century. Meanwhile, studies on myoelectrical control systems focusing on the computation of bio-signal processing and data analysis have been blooming in the recent twenty years. To have a comprehensive view of utilizing facial sEMG method, a systematic review is presented in this paper for facial expression recognition from experiment design to measurement systems, and data analysis steps.

  • 2798.
    Jiang, Xu
    et al.
    Univ Elect Sci & Technol China, Chengdu 611731, Peoples R China..
    Guan, Nan
    Hong Kong Polytech Univ, Hong Kong, Peoples R China..
    Du, He
    Hong Kong Polytech Univ, Hong Kong, Peoples R China.;Northeastern Univ, Shenyang 110032, Peoples R China..
    Liu, Weichen
    Nanyang Technol Univ, Singapore 639798, Singapore..
    Wang, Yi
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    On the Analysis of Parallel Real-Time Tasks With Spin Locks2021In: IEEE Transactions on Computers, ISSN 0018-9340, E-ISSN 1557-9956, Vol. 70, no 2, p. 199-211Article in journal (Refereed)
    Abstract [en]

    Locking protocol is an essential component in resource management of real-time systems, which coordinates mutually exclusive accesses to shared resources from different tasks. Although the design and analysis of locking protocols have been intensively studied for sequential real-time tasks, there has been a little work on this topic for parallel real-time tasks. In this article, we study the analysis of parallel real-time tasks using spin locks to protect accesses to shared resources in three commonly used request serving orders (unordered, FIFO-order, and priority-order). A remarkable feature making our analysis method more accurate is to systematically analyze the blocking time which may delay a task's finishing time, where the impact to the total workload and the longest path length is jointly considered, rather than analyzing them separately and counting all blocking time as the workload that delays a task's finishing time, as commonly assumed in the state-of-the-art.

  • 2799.
    Jiang, Xu
    et al.
    Northeastern Univ, Key Lab Intelligent Comp Med Image, Minist Educ, Shenyang 110819, Liaoning, Peoples R China..
    Liang, Haochun
    Northeastern Univ, Key Lab Intelligent Comp Med Image, Minist Educ, Shenyang 110819, Liaoning, Peoples R China..
    Guan, Nan
    City Univ Hong Kong, Hong Kong, Peoples R China..
    Tang, Yue
    Northeastern Univ, Key Lab Intelligent Comp Med Image, Minist Educ, Shenyang 110819, Liaoning, Peoples R China..
    Qiao, Lei
    Beijing Inst Control Engn, Beijing 100124, Peoples R China..
    Wang, Yi
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems. Northeastern Univ, Key Lab Intelligent Comp Med Image, Minist Educ, Shenyang 110819, Liaoning, Peoples R China..
    Scheduling Parallel Real-Time Tasks on Virtual Processors2023In: IEEE Transactions on Parallel and Distributed Systems, ISSN 1045-9219, E-ISSN 1558-2183, Vol. 34, no 1, p. 33-47Article in journal (Refereed)
    Abstract [en]

    In many popular parallel programming models, e.g., OpenMP (OpenMP, 2013), applications are usually dispatched into several dedicated scheduling entities (named "threads " in common) for which the processor time of physical platform is provided through the OS schedulers. This behavior requires for a hierarchical scheduling framework, considering each thread as a virtual processor (VP). Moreover, hierarchical scheduling allow separate applications to execute together on a common hardware platform, with each application having the "illusion " of executing on a dedicated component. However, the problem for scheduling parallel real-time tasks on virtual multiprocessor platform has not been addressed yet. An analogous approach to virtual scheduling for parallel real-time tasks is federeted scheudling, where each task exclusively executes on a set of dedicated physical processors. However, federated scheduling suffers significant resource wasting. In this article, we study the scheduling of real-time parallel task on virtual multiprocessors. As a physical processor is shared by virtual processors, tasks effectively share processors with each other. We conduct comprehensive performance evaluation to compare our proposed approach with existing methods of different types. Experiment results show that our approach consistently outperforms existing methods to a considerable extent under a wide range of parameter settings.

  • 2800.
    Jiang, Yuning
    University of Skövde, School of Informatics. University of Skövde, Informatics Research Environment.
    Vulnerability Analysis for Critical Infrastructures2022Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The rapid advances in information and communication technology enable a shift from diverse systems empowered mainly by either hardware or software to cyber-physical systems (CPSs) that are driving Critical infrastructures (CIs), such as energy and manufacturing systems. However, alongside the expected enhancements in efficiency and reliability, the induced connectivity exposes these CIs to cyberattacks exemplified by Stuxnet and WannaCry ransomware cyber incidents. Therefore, the need to improve cybersecurity expectations of CIs through vulnerability assessments cannot be overstated. Yet, CI cybersecurity has intrinsic challenges due to the convergence of information technology (IT) and operational technology (OT) as well as the crosslayer dependencies that are inherent to CPS based CIs. Different IT and OT security terminologies also lead to ambiguities induced by knowledge gaps in CI cybersecurity. Moreover, current vulnerability-assessment processes in CIs are mostly subjective and human-centered. The imprecise nature of manual vulnerability assessment operations and the massive volume of data cause an unbearable burden for security analysts. Latest advances in machine-learning (ML) based cybersecurity solutions promise to shift such burden onto digital alternatives. Nevertheless, the heterogeneity, diversity and information gaps in existing vulnerability data repositories hamper accurate assessments anticipated by these ML-based approaches. Therefore, a comprehensive approach is envisioned in this thesis to unleash the power of ML advances while still involving human operators in assessing cybersecurity vulnerabilities within deployed CI networks.Specifically, this thesis proposes data-driven cybersecurity indicators to bridge vulnerability management gaps induced by ad-hoc and subjective auditing processes as well as to increase the level of automation in vulnerability analysis. The proposed methodology follows design science research principles to support the development and validation of scientifically-sound artifacts. More specifically, the proposed data-driven cybersecurity architecture orchestrates a range of modules that include: (i) a vulnerability data model that captures a variety of publicly accessible cybersecurity-related data sources; (ii) an ensemble-based ML pipeline method that self-adjusts to the best learning models for given cybersecurity tasks; and (iii) a knowledge taxonomy and its instantiated power grid and manufacturing models that capture CI common semantics of cyberphysical functional dependencies across CI networks in critical societal domains. This research contributes data-driven vulnerability analysis approaches that bridge the knowledge gaps among different security functions, such as vulnerability management through related reports analysis. This thesis also correlates vulnerability analysis findings to coordinate mitigation responses in complex CIs. More specifically, the vulnerability data model expands the vulnerability knowledge scope and curates meaningful contexts for vulnerability analysis processes. The proposed ML methods fill information gaps in vulnerability repositories using curated data while further streamlining vulnerability assessment processes. Moreover, the CI security taxonomy provides disciplined and coherent support to specify and group semanticallyrelated components and coordination mechanisms in order to harness the notorious complexity of CI networks such as those prevalent in power grids and manufacturing infrastructures. These approaches learn through interactive processes to proactively detect and analyze vulnerabilities while facilitating actionable insights for security actors to make informed decisions.

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