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  • 51.
    Abbas, Nadeem
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Towards autonomic software product lines2011In: SPLC '11 Proceedings of the 15th International Software Product Line Conference, Volume 2, ACM Press, 2011, p. 44:1-44:8Conference paper (Refereed)
    Abstract [en]

    We envision an Autonomic Software Product Line (ASPL). The ASPL is a dynamic software product line that supports self adaptable products. We plan to use reflective architecture to model and develop ASPL. To evaluate the approach, we have implemented three autonomic product lines which show promising results. The ASPL approach is at initial stages, and require additional work. We plan to exploit online learning to realize more dynamic software product lines to cope with the problem of product line evolution. We propose on-line knowledge sharing among products in a product line to achieve continuous improvement of quality in product line products.

  • 52.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Architectural reasoning for dynamic software product lines2013In: Proceedings of the 17th International Software Product Line Conference co-located workshops, ACM Press, 2013, p. 117-124Conference paper (Refereed)
    Abstract [en]

    Software quality is critical in today's software systems. A challenge is the trade-off situation architects face in the design process. Designers often have two or more alternatives, which must be compared and put into context before a decision is made. The challenge becomes even more complex for dynamic software product lines, where domain designers have to take runtime variations into consideration as well. To address the problem we propose extensions to an architectural reasoning framework with constructs/artifacts to define and model a domain's scope and dynamic variability. The extended reasoning framework encapsulates knowledge to understand and reason about domain quality behavior and self-adaptation as a primary variability mechanism. The framework is demonstrated for a self-configuration property, self-upgradability on an educational product-line.

  • 53.
    Abbas, Nadeem
    et al.
    EcoFES.
    Andersson, Jesper
    EcoFES.
    Architectural Reasoning Support for Product-Lines of Self-adaptive Software Systems - A Case Study2015In: Software Architecture: 9th European Conference, ECSA 2015, Dubrovnik/Cavtat, Croatia, September 7-11, 2015. Proceedings, Springer International Publishing , 2015, 17, p. 20-36Chapter in book (Refereed)
    Abstract [en]

    Software architecture serves as a foundation for the design and development of software systems. Designing an architecture requires extensive analysis and reasoning. The study presented herein focuses on the architectural analysis and reasoning in support of engineering self-adaptive software systems with systematic reuse. Designing self-adaptive software systems with systematic reuse introduces variability along three dimensions; adding more complexity to the architectural analysis and reasoning process. To this end, the study presents an extended Architectural Reasoning Framework with dedicated reasoning support for self-adaptive systems and reuse. To evaluate the proposed framework, we conducted an initial feasibility case study, which concludes that the proposed framework assists the domain architects to increase reusability, reduce fault density, and eliminate differences in skills and experiences among architects, which were our research goals and are decisive factors for a system’s overall quality.

  • 54.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Architectural Reasoning Support for Product-Lines of Self-adaptive Software Systems: A Case Study2015In: Software Architecture: 9th European Conference, ECSA 2015, Dubrovnik/Cavtat, Croatia, September 7-11, 201 / [ed] Danny Weyns, Raffaela Mirandola, Ivica Crnkovic, 2015, p. 20-36Conference paper (Refereed)
    Abstract [en]

    Software architecture serves as a foundation for the design and development of software systems. Designing an architecture requires extensive analysis and reasoning. The study presented herein focuses on the architectural analysis and reasoning in support of engineering self-adaptive software systems with systematic reuse. Designing self-adaptive software systems with systematic reuse introduces variability along three dimensions; adding more complexity to the architectural analysis and reasoning process. To this end, the study presents an extended Architectural Reasoning Framework with dedicated reasoning support for self-adaptive systems and reuse. To evaluate the proposed framework, we conducted an initial feasibility case study, which concludes that the proposed framework assists the domain architects to increase reusability, reduce fault density, and eliminate differences in skills and experiences among architects, which were our research goals and are decisive factors for a system's overall quality.

  • 55.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM), Department of Computer Science.
    ASPLe: a methodology to develop self-adaptive software systems with reuse2017Report (Other academic)
    Abstract [en]

    Advances in computing technologies are pushing software systems and their operating environments to become more dynamic and complex. The growing complexity of software systems coupled with uncertainties induced by runtime variations leads to challenges in software analysis and design. Self-Adaptive Software Systems (SASS) have been proposed as a solution to address design time complexity and uncertainty by adapting software systems at runtime. A vast body of knowledge on engineering self-adaptive software systems has been established. However, to the best of our knowledge, no or little work has considered systematic reuse of this knowledge. To that end, this study contributes an Autonomic Software Product Lines engineering (ASPLe) methodology. The ASPLe is based on a multi-product lines strategy which leverages systematic reuse through separation of application and adaptation logic. It provides developers with repeatable process support to design and develop self-adaptive software systems with reuse across several application domains. The methodology is composed of three core processes, and each process is organized for requirements, design, implementation, and testing activities. To exemplify and demonstrate the use of the ASPLe methodology, three application domains are used as running examples throughout the report.

  • 56.
    Abbas, Nadeem
    et al.
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory. Linnaeus University.
    Andersson, Jesper
    RISE, Swedish ICT, SICS, Software and Systems Engineering Laboratory. Linnaeus University.
    Harnessing Variability in Product-lines of Self-adaptive Software Systems2015Conference paper (Refereed)
    Abstract [en]

    This work studies systematic reuse in the context of self-adaptive software systems. In our work, we realized that managing variability for such platforms is different compared to traditional platforms, primarily due to the run-time variability and system uncertainties. Motivated by the fact that recent trends show that self-adaptation will be used more often in future system generation and that software reuse state-of-practice or research do not provide sufficient support, we have investigated the problems and possibly resolutions in this context. We have analyzed variability for these systems, using a systematic reuse prism, and identified a research gap in variability management. The analysis divides variability handling into four activities: (1) identify variability, (2) constrain variability, (3) implement variability, and (4) manage variability. Based on the findings we envision a reuse framework for the specific domain and present an example framework that addresses some of the identified challenges. We argue that it provides basic support for engineering self-adaptive software systems with systematic reuse. We discuss some important avenues of research for achieving the vision.

  • 57.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Harnessing Variability in Product-lines of Self-adaptive Software Systems2015In: Proceedings of the 19th International Conference on Software Product Line: SPLC '15, ACM Press, 2015, p. 191-200Conference paper (Refereed)
    Abstract [en]

    This work studies systematic reuse in the context of self-adaptive software systems. In our work, we realized that managing variability for such platforms is different compared to traditional platforms, primarily due to the run-time variability and system uncertainties. Motivated by the fact that recent trends show that self-adaptation will be used more often in future system generation and that software reuse state-of-practice or research do not provide sufficient support, we have investigated the problems and possibly resolutions in this context. We have analyzed variability for these systems, using a systematic reuse prism, and identified a research gap in variability management. The analysis divides variability handling into four activities: (1) identify variability, (2) constrain variability, (3) implement variability, and (4) manage variability. Based on the findings we envision a reuse framework for the specific domain and present an example framework that addresses some of the identified challenges. We argue that it provides basic support for engineering self-adaptive software systems with systematic reuse. We discuss some important avenues of research for achieving the vision.

  • 58.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Iftikhar, Muhammad Usman
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Rigorous architectural reasoning for self-adaptive software systems2016In: Proceedings: First Workshop on Qualitative Reasoning abut Software Architectures, QRASA 2016 / [ed] Lisa O'Conner, IEEE, 2016, p. 11-18Conference paper (Refereed)
    Abstract [en]

    Designing a software architecture requires architectural reasoning, i.e., activities that translate requirements to an architecture solution. Architectural reasoning is particularly challenging in the design of product-lines of self-adaptive systems, which involve variability both at development time and runtime. In previous work we developed an extended Architectural Reasoning Framework (eARF) to address this challenge. However, evaluation of the eARF showed that the framework lacked support for rigorous reasoning, ensuring that the design complies to the requirements. In this paper, we introduce an analytical framework that enhances eARF with such support. The framework defines a set of artifacts and a series of activities. Artifacts include templates to specify domain quality attribute scenarios, concrete models, and properties. The activities support architects with transforming requirement scenarios to architecture models that comply to required properties. Our focus in this paper is on architectural reasoning support for a single product instance. We illustrate the benefits of the approach by applying it to an example client-server system, and outline challenges for future work. © 2016 IEEE.

  • 59.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Andersson, Jesper
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Löwe, Welf
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Autonomic Software Product Lines (ASPL)2010In: ECSA '10 Proceedings of the Fourth European Conference on Software Architecture: Companion Volume / [ed] Carlos E. Cuesta, ACM Press, 2010, p. 324-331Conference paper (Refereed)
    Abstract [en]

    We describe ongoing work on a variability mechanism for Autonomic Software Product Lines (ASPL). The autonomic software product lines have self-management characteristics that make product line instances more resilient to context changes and some aspects of product line evolution. Instances sense the context, selects and bind the best component variants to variation-points at run-time. The variability mechanism we describe is composed of a profile guided dispatch based on off-line and on-line training processes. Together they form a simple, yet powerful variability mechanism that continuously learns, which variants to bind given the current context and system goals.

  • 60.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Andersson, Jesper
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Löwe, Welf
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Towards Autonomic Software Product Lines (ASPL) - A Technical Report2011Report (Other academic)
    Abstract [en]

    This report describes a work in progress to develop Autonomic Software Product Lines (ASPL). The ASPL is a dynamic software product line approach with a novel variability handling mechanism that enables traditional software product lines to adapt themselves at runtime in response to changes in their context, requirements and business goals. The ASPL variability mechanism is composed of three key activities: 1) context-profiling, 2) context-aware composition, and 3) online learning. Context-profiling is an offline activity that prepares a knowledge base for context-aware composition. The context-aware composition uses the knowledge base to derive a new product or adapts an existing product based on a product line's context attributes and goals. The online learning optimizes the knowledge base to remove errors and suboptimal information and to incorporate new knowledge. The three activities together form a simple yet powerful variability handling mechanism that learns and adapts a system at runtime in response to changes in system context and goals. We evaluated the ASPL variability mechanism on three small-scale software product lines and got promising results. The ASPL approach is, however, is yet at an initial stage and require improved development support with more rigorous evaluation. 

  • 61.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Andersson, Jesper
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    ASPLe: a methodology to develop self-adaptive software systems with systematic reuseManuscript (preprint) (Other academic)
    Abstract [en]

    More than two decades of research have demonstrated an increasing need for software systems to be self-adaptive. Self-adaptation is required to deal with runtime dynamics which are difficult to predict before deployment. A vast body of knowledge to develop Self-Adaptive Software Systems (SASS) has been established. We, however, discovered a lack of process support to develop self-adaptive systems with reuse. To that end, we propose a domain-engineering based methodology, Autonomic Software Product Lines engineering (ASPLe), which provides step-by-step guidelines for developing families of SASS with systematic reuse. The evaluation results from a case study show positive effects on quality and reuse for self-adaptive systems designed using the ASPLe compared to state-of-the-art engineering practices.

  • 62.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Andersson, Jesper
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Weyns, Danny
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Knowledge evolution in autonomic software product lines2011In: SPLC '11 Proceedings of the 15th International Software Product Line Conference, Volume 2, New York, NY, USA: ACM Press, 2011, p. 36:1-36:8Conference paper (Refereed)
    Abstract [en]

    We describe ongoing work in knowledge evolution management for autonomic software product lines. We explore how an autonomic product line may benefit from new knowledge originating from different source activities and artifacts at run time. The motivation for sharing run-time knowledge is that products may self-optimize at run time and thus improve quality faster compared to traditional software product line evolution. We propose two mechanisms that support knowledge evolution in product lines: online learning and knowledge sharing. We describe two basic scenarios for runtime knowledge evolution that involves these mechanisms. We evaluate online learning and knowledge sharing in a small product line setting that shows promising results.

  • 63.
    Abbas, Nadeem
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Andersson, Jesper
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Weyns, Danny
    Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
    Modeling Variability in Product Lines Using Domain Quality Attribute Scenarios2012In: Proceedings of the WICSA/ECSA 2012 Companion Volume, ACM Press, 2012, p. 135-142Conference paper (Refereed)
    Abstract [en]

    The concept of variability is fundamental in software product lines and a successful implementation of a product line largely depends on how well domain requirements and their variability are specified, managed, and realized. While developing an educational software product line, we identified a lack of support to specify variability in quality concerns. To address this problem we propose an approach to model variability in quality concerns, which is an extension of quality attribute scenarios. In particular, we propose domain quality attribute scenarios, which extend standard quality attribute scenarios with additional information to support specification of variability and deriving product specific scenarios. We demonstrate the approach with scenarios for robustness and upgradability requirements in the educational software product line.

  • 64.
    Abbas, Qaisar
    et al.
    Uppsala universitet, Avdelningen för teknisk databehandling.
    Nordström, Jan
    Uppsala universitet, Avdelningen för teknisk databehandling.
    Weak versus strong no-slip boundary conditions for the Navier-Stokes equations2010In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, Vol. 4, p. 29-38Article in journal (Refereed)
  • 65.
    Abbas, Qaisar
    et al.
    Uppsala universitet, Avdelningen för teknisk databehandling.
    Nordström, Jan
    Uppsala universitet, Avdelningen för teknisk databehandling.
    Weak versus Strong No-Slip Boundary Conditions for the Navier-Stokes Equations2008In: Proc. 6th South African Conference on Computational and Applied Mechanics, South African Association for Theoretical and Applied Mechanics , 2008, p. 52-62Conference paper (Other academic)
  • 66.
    Abbas, Qaisar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Nordström, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Weak versus strong no-slip boundary conditions for the Navier-Stokes equations2010In: Engineering Applications of Computational Fluid Mechanics, ISSN 1994-2060, Vol. 4, p. 29-38Article in journal (Refereed)
  • 67.
    Abbas, Qaisar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Nordström, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Weak versus Strong No-Slip Boundary Conditions for the Navier-Stokes Equations2008In: Proc. 6th South African Conference on Computational and Applied Mechanics, South African Association for Theoretical and Applied Mechanics , 2008, p. 52-62Conference paper (Other academic)
  • 68.
    Abbas, Qaisar
    et al.
    Uppsala universitet, Avdelningen för teknisk databehandling.
    van der Weide, Edwin
    Nordström, Jan
    Uppsala universitet, Avdelningen för teknisk databehandling.
    Accurate and stable calculations involving shocks using a new hybrid scheme2009In: Proc. 19th AIAA CFD Conference, AIAA , 2009Conference paper (Refereed)
  • 69.
    Abbas, Qaisar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    van der Weide, Edwin
    Nordström, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Numerical Analysis.
    Accurate and stable calculations involving shocks using a new hybrid scheme2009In: Proc. 19th AIAA CFD Conference, AIAA , 2009Conference paper (Refereed)
  • 70.
    Abbas, Sahib
    KTH, School of Information and Communication Technology (ICT).
    Lösning till mobilitetsproblem samt tillgänglighet till hemsidan för Iraks ambassad2014Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att använda internet nuförtiden har blivit en del av vardagen. Det känns som att Internet har delat världen i många delar där varje del delar med sig information i många olika former som placeras i olika kategorier. Vi delar information på många olika sätt, men det snabbaste och lättaste sättet är att sprida information med internet.

    Tekniken kommer med nya ideer kontinuerligt och vi utvecklar nya metoder som gör det ännu lättare för oss människor att få in information som vi forsöker att nå via internet. Två av de mest kända sätten där man kan dela med sig information är hemsidor och med "native" applikationer.

    Jag utförde exjobbet på lrakiska ambassaden. Det är en statlig irakisk organisation som ligger pa Baldersgatan 6A Stockholm. Huvuduppgift på ambassaden är att hjälpa irakisk- ­och icke irakiska medborgare som är bosatta i Sverige med vissa uppgifter.

    Ambassaden har mycket information som de försöker att dela med sig så mycket som möjligt av via hemsidan så att de minskar av det strulet de har. Hemsidan som ambassaden hade var ostrukturerad, och hade en tråkig design som ledde till att användaren fick svårigbeter med att lätt hitta det man söker.

    Detta examensarbete presenterar min lösning av problemen till ambassaden. Den är att bygga en helt ny hemsida som är mobilanpassad, som har bättre design ocb är mer strukturerad hemsida än den gamla hemsidan de hade. På så sätt så blir det mycket lättare för användaren att använda hemsidan. Samtidigt löser den mobilitetsproblemet, eftersom ambassaden började med att utveckla en native app till Iphone men projektet avbröts halvvägs för att det kostade för mycket och man insåg att det skulle uppstå ännu mer kostnader for att utveckla native appar till android ocb övriga operativ systemen. Detta examensarbete beskriver också hur man skulle kunna utveckla en mobilanpassad hemsida, vilka metoder ocb modeller som jag har använt mig av till utvecklingen av hemsidan, samt resultaten jag hade fått av de metoder som användes till utveckling av detta projekt.

  • 71.
    Abbas, Syed Muhammad
    et al.
    Jönköping University, School of Engineering, JTH, Computer and Electrical Engineering. Jönköping University, School of Engineering. Jönköping University.
    Henricsson, Christopher
    Jönköping University, School of Engineering, JTH, Computer and Electrical Engineering. Jönköping University, School of Engineering. Jönköping University.
    A Simulation Framework for Efficient Search in P2P Networks with 8-Point HyperCircles2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report concerns the implementation of a simulation framework to evaluate an emerging peer-to-peer network topology scheme using 8-point hypercircles, entitled HyperCircle. This topology was proposed in order to alleviate some of the drawbacks of current P2P systems evolving in an uncontrolled manner, such as scalability issues, network overload and long search times. The framework is supposed to be used to evaluate the advantages of this new topology. The framework has been built on top of an existing simulator software solution, the selection of which was an important part of the development. Weighing different variables such as scalability and API usability, the selection fell on OverSim, an open-source discreet-event simulator based on OMNET++.

    After formalizing the protocol for easier implementation, as well as extending it for better performance, implementation followed using C++ with OverSim’s API and simulation library. Implemented as a module (alongside other stock modules providing their own protocols such as Chord and Kademlia), it can be used in OverSim to simulate a user-defined network using one of the simulation routine applications provided (or using a custom application written by the user). For the purposes of this thesis, the standard application KBRTestApp was used; an application sending test messages between randomly selected nodes, while adding and removing nodes at specific time intervals. The adding and removing of nodes can be configured with probability parameters.

    Tentative testing shows that this implementation of the HyperCircle protocol has a certain performance gain over the OverSim implementations of the Chord and Kademlia protocols, measurable in the time it takes a message to get from sender to recipient. Further testing is outside the scope of this thesis.

  • 72. Abbasi, A. G.
    et al.
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Computer and Systems Sciences, DSV.
    Schmölzer, Gernot
    KTH, School of Information and Communication Technology (ICT), Computer and Systems Sciences, DSV.
    CryptoNET: Secure federation protocol and authorization policies for SMI2009In: Post-Proceedings of the 4th International Conference on Risks and Security of Internet and Systems, CRiSIS 2009, 2009, p. 19-25Conference paper (Refereed)
    Abstract [en]

    The paper describes a protocol for Secure E-Mail Infrastructure for establishing trust between different domains in order to protect mail servers from spam messages. The protocol uses messages for trusted interactions between intra and inter E-mail domain components, Secure E-mail (SEM) servers and Secure Mail Infrastructure (SMI) servers. In addition, the protocol validates E-mail addresses thus guaranteeing to the recipient that the E-mail is coming from a trusted domain. We also use XACML-based authorization policies at the sending and receiving servers, enforced by associated Policy Enforcement Point (PEP) servers at SEM servers, in order to provide a complete protection against spam.

  • 73.
    Abbasi, Abdul Ghafoor
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    CryptoNET: Generic Security Framework for Cloud Computing Environments2011Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The area of this research is security in distributed environment such as cloud computing and network applications. Specific focus was design and implementation of high assurance network environment, comprising various secure and security-enhanced applications. “High Assurance” means that

    -               our system is guaranteed to be secure,

    -               it is verifiable to provide the complete set of security services,

    -               we prove that it always functions correctly, and

    -               we justify our claim that it can not be compromised without user neglect and/or consent.

     

    We do not know of any equivalent research results or even commercial security systems with such properties. Based on that, we claim several significant research and also development contributions to the state–of–art of computer networks security.

    In the last two decades there were many activities and contributions to protect data, messages and other resources in computer networks, to provide privacy of users, reliability, availability and integrity of resources, and to provide other security properties for network environments and applications. Governments, international organizations, private companies and individuals are investing a great deal of time, efforts and budgets to install and use various security products and solutions. However, in spite of all these needs, activities, on-going efforts, and all current solutions, it is general belief that the security in today networks and applications is not adequate.

    At the moment there are two general approaches to network application’s security. One approach is to enforce isolation of users, network resources, and applications. In this category we have solutions like firewalls, intrusion–detection systems, port scanners, spam filters, virus detection and elimination tools, etc. The goal is to protect resources and applications by isolation after their installation in the operational environment. The second approach is to apply methodology, tools and security solutions already in the process of creating network applications. This approach includes methodologies for secure software design, ready–made security modules and libraries, rules for software development process, and formal and strict testing procedures. The goal is to create secure applications even before their operational deployment. Current experience clearly shows that both approaches failed to provide an adequate level of security, where users would be guaranteed to deploy and use secure, reliable and trusted network applications.

    Therefore, in the current situation, it is obvious that a new approach and a new thinking towards creating strongly protected and guaranteed secure network environments and applications are needed. Therefore, in our research we have taken an approach completely different from the two mentioned above. Our first principle is to use cryptographic protection of all application resources. Based on this principle, in our system data in local files and database tables are encrypted, messages and control parameters are encrypted, and even software modules are encrypted. The principle is that if all resources of an application are always encrypted, i.e. “enveloped in a cryptographic shield”, then

    -               its software modules are not vulnerable to malware and viruses,

    -               its data are not vulnerable to illegal reading and theft,

    -               all messages exchanged in a networking environment are strongly protected, and

    -               all other resources of an application are also strongly protected.

     

    Thus, we strongly protect applications and their resources before they are installed, after they are deployed, and also all the time during their use.

    Furthermore, our methodology to create such systems and to apply total cryptographic protection was based on the design of security components in the form of generic security objects. First, each of those objects – data object or functional object, is itself encrypted. If an object is a data object, representing a file, database table, communication message, etc., its encryption means that its data are protected all the time. If an object is a functional object, like cryptographic mechanisms, encapsulation module, etc., this principle means that its code cannot be damaged by malware. Protected functional objects are decrypted only on the fly, before being loaded into main memory for execution. Each of our objects is complete in terms of its content (data objects) and its functionality (functional objects), each supports multiple functional alternatives, they all provide transparent handling of security credentials and management of security attributes, and they are easy to integrate with individual applications. In addition, each object is designed and implemented using well-established security standards and technologies, so the complete system, created as a combination of those objects, is itself compliant with security standards and, therefore, interoperable with exiting security systems.

    By applying our methodology, we first designed enabling components for our security system. They are collections of simple and composite objects that also mutually interact in order to provide various security services. The enabling components of our system are:  Security Provider, Security Protocols, Generic Security Server, Security SDKs, and Secure Execution Environment. They are all mainly engine components of our security system and they provide the same set of cryptographic and network security services to all other security–enhanced applications.

    Furthermore, for our individual security objects and also for larger security systems, in order to prove their structural and functional correctness, we applied deductive scheme for verification and validation of security systems. We used the following principle: “if individual objects are verified and proven to be secure, if their instantiation, combination and operations are secure, and if protocols between them are secure, then the complete system, created from such objects, is also verifiably secure”. Data and attributes of each object are protected and secure, and they can only be accessed by authenticated and authorized users in a secure way. This means that structural security properties of objects, upon their installation, can be verified. In addition, each object is maintained and manipulated within our secure environment so each object is protected and secure in all its states, even after its closing state, because the original objects are encrypted and their data and states stored in a database or in files are also protected.

    Formal validation of our approach and our methodology is performed using Threat Model. We analyzed our generic security objects individually and identified various potential threats for their data, attributes, actions, and various states. We also evaluated behavior of each object against potential threats and established that our approach provides better protection than some alternative solutions against various threats mentioned. In addition, we applied threat model to our composite generic security objects and secure network applications and we proved that deductive approach provides better methodology for designing and developing secure network applications. We also quantitatively evaluated the performance of our generic security objects and found that the system developed using our methodology performs cryptographic functions efficiently.

    We have also solved some additional important aspects required for the full scope of security services for network applications and cloud environment: manipulation and management of cryptographic keys, execution of encrypted software, and even secure and controlled collaboration of our encrypted applications in cloud computing environments. During our research we have created the set of development tools and also a development methodology which can be used to create cryptographically protected applications. The same resources and tools are also used as a run–time supporting environment for execution of our secure applications. Such total cryptographic protection system for design, development and run–time of secure network applications we call CryptoNET system. CrytpoNET security system is structured in the form of components categorized in three groups: Integrated Secure Workstation, Secure Application Servers, and Security Management Infrastructure Servers. Furthermore, our enabling components provide the same set of security services to all components of the CryptoNET system.

    Integrated Secure Workstation is designed and implemented in the form of a collaborative secure environment for users. It protects local IT resources, messages and operations for multiple applications. It comprises four most commonly used PC applications as client components: Secure Station Manager (equivalent to Windows Explorer), Secure E-Mail Client, Secure Web Browser, and Secure Documents Manager. These four client components for their security extensions use functions and credentials of the enabling components in order to provide standard security services (authentication, confidentiality, integrity and access control) and also additional, extended security services, such as transparent handling of certificates, use of smart cards, Strong Authentication protocol, Security Assertion Markup Language (SAML) based Single-Sign-On protocol, secure sessions, and other security functions.

    Secure Application Servers are components of our secure network applications: Secure E-Mail Server, Secure Web Server, Secure Library Server, and Secure Software Distribution Server. These servers provide application-specific services to client components. Some of the common security services provided by Secure Application Servers to client components are Single-Sign-On protocol, secure communication, and user authorization. In our system application servers are installed in a domain but it can be installed in a cloud environment as services. Secure Application Servers are designed and implemented using the concept and implementation of the Generic Security Server. It provides extended security functions using our engine components. So by adopting this approach, the same sets of security services are available to each application server.

    Security Management Infrastructure Servers provide domain level and infrastructure level services to the components of the CryptoNET architecture. They are standard security servers, known as cloud security infrastructure, deployed as services in our domain level could environment.

    CryptoNET system is complete in terms of functions and security services that it provides. It is internally integrated, so that the same cryptographic engines are used by all applications. And finally, it is completely transparent to users – it applies its security services without expecting any special interventions by users. In this thesis, we developed and evaluated secure network applications of our CryptoNET system and applied Threat Model to their validation and analysis. We found that deductive scheme of using our generic security objects is effective for verification and testing of secure, protected and verifiable secure network applications.

    Based on all these theoretical research and practical development results, we believe that our CryptoNET system is completely and verifiably secure and, therefore, represents a significant contribution to the current state-of-the-art of computer network security.

  • 74.
    Abbasi, Abdul Ghafoor
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS.
    CryptoNET: Security Management Protocols2010In: ADVANCES IN DATA NETWORKS, COMMUNICATIONS, COMPUTERS / [ed] Mastorakis, NE; Mladenov, V, ATHENS: WORLD SCIENTIFIC AND ENGINEERING ACAD AND SOC , 2010, p. 15-20Conference paper (Refereed)
    Abstract [en]

    In this paper we describe several network security protocols used by various components of CryptoNET architecture. The protocols are based on the concept of generic security objects and on well-established security standards and technologies. Distinctive features of our security protocols are: (1) they are complete in terms of their functionality, (2) they are easy to integrate with applications, (3) they transparently handle security credentials and protocol-specific attributes using FIPS 201 (PIV) smart cards, and (4) they are based on generic security objects. These protocols are: remote user authentication protocol, single-sign-on protocol, SAML authorization protocol, and secure sessions protocol. Security protocols use our Security Provider as a collection of cryptographic engines implemented either in software or using FIPS 201 (NV) smart cards. It also manages protocols' attributes using security applets stored in Ply smart card.

  • 75.
    Abbasi, Abdul Ghafoor
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Hotamov, I.
    Web contents protection, secure execution and authorized distribution2010In: Proceedings - 5th International Multi-Conference on Computing in the Global Information Technology, ICCGI 2010, 2010, p. 157-162Conference paper (Refereed)
    Abstract [en]

    This paper describes the design and implementation of a comprehensive system for protection of Web contents. In this design, new security components and extended security features are introduced in order to protect Web contents ageist various Web attacks. Components and extended security features are: protection of Web pages using strong encryption techniques, encapsulation of Web contents and resources in PKCS#7, extended secure execution environment for Java Web Server, eXtensible Access Control Markup Language (XACML) based authorization policies, and secure Web proxy. Design and implementation of our system is based on the concepts of generic security objects and component-based architecture that makes it compatible with exiting Web infrastructures without any modification.

  • 76.
    Abbasi, Azad Ismail
    KTH, School of Computer Science and Communication (CSC).
    Coffeepot for Masochists: A Study in User-Centered System Design2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Coffeepot for Masochists

    A Study in User-Centered System Design

     

    This master thesis is carried out in the field of “Human-Computer interaction”, more specifically the area “User-centered system design”. The focus has been on “usability” and useful graphical user interfaces. Current theories and definitions in the field have been considered. Literature studies contain well known authors and organisations in domains mentioned above; Jakob Nielsen, Donald A Norman and International Organization for Standardization ISO to mention some.

     

    Another source for this work from which the theories and way of working have been used is the book “User-Centered System Design” written by Jan Gulliksen and Bengt Göransson.

     

    The work started with a literature study followed by looking at methods to use. The next step was to do task and user analysis which followed by the development phase. The user has been given a central role in this project and, just as recommended, also been involved through the whole cycle. A useful method to get feedback from users, in addition to interviews and workshops, has been the “Heuristic Evaluation”.

     

    The final result and conclusion shows that the user-centered system design is a powerful tool to adapt when designing and developing interactive user interface.

  • 77.
    Abbaspour Asadollah, Sara
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Daniel, Sundmark
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Eldh, S.
    Ericsson AB, Stockholm, Sweden.
    Hansson, Hans
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Concurrency bugs in open source software: a case study2017In: Journal of Internet Services and Applications, ISSN 1867-4828, Vol. 8, no 1, article id 4Article in journal (Refereed)
    Abstract [en]

    Concurrent programming puts demands on software debugging and testing, as concurrent software may exhibit problems not present in sequential software, e.g., deadlocks and race conditions. In aiming to increase efficiency and effectiveness of debugging and bug-fixing for concurrent software, a deep understanding of concurrency bugs, their frequency and fixing-times would be helpful. Similarly, to design effective tools and techniques for testing and debugging concurrent software, understanding the differences between non-concurrency and concurrency bugs in real-word software would be useful. This paper presents an empirical study focusing on understanding the differences and similarities between concurrency bugs and other bugs, as well as the differences among various concurrency bug types in terms of their severity and their fixing time, and reproducibility. Our basis is a comprehensive analysis of bug reports covering several generations of five open source software projects. The analysis involves a total of 11860 bug reports from the last decade, including 351 reports related to concurrency bugs. We found that concurrency bugs are different from other bugs in terms of their fixing time and severity while they are similar in terms of reproducibility. Our findings shed light on concurrency bugs and could thereby influence future design and development of concurrent software, their debugging and testing, as well as related tools.

  • 78. Abbaspour Assadollah, Sara
    et al.
    Saadatmand, Mehrdad
    RISE, Swedish ICT, SICS.
    Sundmark, Daniel
    Hansson, Hans
    A Model for Systematic Monitoring and Debugging of Starvation Bugs in Multicore Software2016Conference paper (Refereed)
    Abstract [en]

    With the development of multicore hardware, concurrent, parallel and multicore software are becoming increasingly popular. Software companies are spending a huge amount of time and resources to nd and debug the bugs. Among all types of software bugs, concurrency bugs are also important and troublesome. This type of bugs is increasingly becoming an issue particularly due to the growing prevalence of multicore hardware. In this position paper, we propose a model for monitoring and debugging Starvation bugs as a type of concurrency bugs in multicore software. The model is composed into three phases: monitoring, detecting and debugging. The monitoring phase can support detecting phase by storing collected data from the system execution. The detecting phase can support debugging phase by comparing the stored data with starvation bug's properties, and the debugging phase can help in reproducing and removing the Starvation bug from multicore software. Our intention is that our model is the basis for developing tool(s) to enable solving Starvation bugs in software for multicore platforms.

  • 79.
    Abbassi, Selma
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Engström, Rickard
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Algoritm för lokalisering av referensnoder med Indoor Positioning System2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Indoor Positioning Systems lokaliserar människor och objekt inomhus med hjälp av minst tre kända referenspunkter. System för inomhuspositionering som använder kända referenspunkter kallas anchor-based lokalisering medan de som beräknar deras positioner själva kallas anchor-free lokalisering. Syftet med detta arbete är att utveckla en algoritm som är anpassad efter ett anchor-free lokaliseringssystem. Den ska vara oberoende av nätverksuppkopplingen, hårdvaran och hur avstånden mellan mottagare och sensorer beräknats. Utgångspunkten för algoritmen är enbart avstånd mellan en mottagare och tre sensorer vilket kan beskrivas som arbetets huvudsakliga problem.

    Algoritmen implementerades i Java med en simulering som återspeglar positioneringen i en perfekt miljö och sedan testas på en Android-applikation. Simuleringen tillåter användaren att rita ut flera mätpunkter som skapar en rutt. Dessa mätpunkter utnyttjas för att dynamiskt lokalisera referenspunkterna och mätpunkterna genom att hitta ett minsta avstånd mellan sensorerna. Dessa avstånd kan beskrivas som sidorna för en referenstriangel som möjliggör att ett koordinatsystem kan spännas upp.

    Resultatet av den empiriska studien visade en felmarginal mellan 0,3-6 m utan signalstörningar, vilket inte var tillräckligt noggrant. Efter att algoritmen implementerats lades fokus på en korrigering som kan itereras igenom för att uppskatta bättre mätvärden för referenstriangeln. Korrigeringen gav positiva resultat med lägre felmarginal. Arbetet kan vidareutvecklas genom att implementeras i ett verkligt IPS-system och algoritmen kan förbättras genom att skapa utökade funktioner som kan hantera fler än tre beacons.

  • 80.
    Abbaszadeh, Sepideh
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Espinoza, Daniela
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Instagram: en plattform för att frigöra kvinnors kroppar genom hashtags.: Ett bidrag i diskussionen angående aktivism på Instagram.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The naked body is an entity that has always been present in both the “real” world and the media. The anatomy of our bodies isn’t something we can avoid; today it reflects the reality that has developed partly from media. According to Instagram’s guidelines users are not allowed to publish naked or semi-naked pictures but that does not stop certain users that are critical to how the body norms and censorship are portrait today. In our study, we take part of research regarding gender in multimedia settings and how they have affected our daily lives. As well as studies, which research the usage of hashtags and how to circumvent censorship. The focus for this study is to research what role Instagram and hashtags have in generating a public discussion as well to draw attention to various issues and causes that are based on norm critique. We have conducted two different observations, held interviews with activists and created an online-survey for users to answer what they think about the Instagram community guidelines. The results show that there is an underlying discrimination acceptance within Instagram and their community guidelines. We can also see that women and users who uses hashtags can spread their causes more effectively, although they are simultaneously at risk for being censored depending on the hashtag they use. According to our respondents from our research there is an agreement regarding the need of updating Instagram’s community guidelines, which could help with eliminate the current discrimination against women and their breasts. At the end of this study we are giving a proposal to how Instagram can work with their censoring in a more critical way. This may contribute to an agenda to make social media platforms safer and less discriminating.

  • 81.
    Abbaszadeh Shahri, Abbas
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering. Islamic Azad University.
    An Optimized Artificial Neural Network Structure to Predict Clay Sensitivity in a High Landslide Prone Area Using Piezocone Penetration Test (CPTu) Data: A Case Study in Southwest of Sweden2016In: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529, p. 1-14Article in journal (Refereed)
    Abstract [en]

    Application of artificial neural networks (ANN) in various aspects of geotechnical engineering problems such as site characterization due to have difficulty to solve or interrupt through conventional approaches has demonstrated some degree of success. In the current paper a developed and optimized five layer feed-forward back-propagation neural network with 4-4-4-3-1 topology, network error of 0.00201 and R2 = 0.941 under the conjugate gradient descent ANN training algorithm was introduce to predict the clay sensitivity parameter in a specified area in southwest of Sweden. The close relation of this parameter to occurred landslides in Sweden was the main reason why this study is focused on. For this purpose, the information of 70 piezocone penetration test (CPTu) points was used to model the variations of clay sensitivity and the influences of direct or indirect related parameters to CPTu has been taken into account and discussed in detail. Applied operation process to find the optimized ANN model using various training algorithms as well as different activation functions was the main advantage of this paper. The performance and feasibility of proposed optimized model has been examined and evaluated using various statistical and analytical criteria as well as regression analyses and then compared to in situ field tests and laboratory investigation results. The sensitivity analysis of this study showed that the depth and pore pressure are the two most and cone tip resistance is the least effective factor on prediction of clay sensitivity.

  • 82.
    Abbay, Kissery
    Örebro University, Swedish Business School at Örebro University.
    Gender Vis-à-vis Swedish Municipal Web sites2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 83. Abbeloos, W.
    et al.
    Caccamo, Sergio
    KTH, School of Computer Science and Communication (CSC), Robotics, perception and learning, RPL.
    Ataer-Cansizoglu, E.
    Taguchi, Y.
    Feng, C.
    Lee, T. -Y
    Detecting and Grouping Identical Objects for Region Proposal and Classification2017In: 2017 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops, IEEE Computer Society, 2017, Vol. 2017, p. 501-502, article id 8014810Conference paper (Refereed)
    Abstract [en]

    Often multiple instances of an object occur in the same scene, for example in a warehouse. Unsupervised multi-instance object discovery algorithms are able to detect and identify such objects. We use such an algorithm to provide object proposals to a convolutional neural network (CNN) based classifier. This results in fewer regions to evaluate, compared to traditional region proposal algorithms. Additionally, it enables using the joint probability of multiple instances of an object, resulting in improved classification accuracy. The proposed technique can also split a single class into multiple sub-classes corresponding to the different object types, enabling hierarchical classification.

  • 84.
    Abbireddy, Sharath
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    A Model for Capacity Planning in Cassandra: Case Study on Ericsson’s Voucher System2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cassandra is a NoSQL(Not only Structured Query Language) database which serves large amount of data with high availability .Cassandra data storage dimensioning also known as Cassandra capacity planning refers to predicting the amount of disk storage required when a particular product is deployed using Cassandra. This is an important phase in any product development lifecycle involving Cassandra data storage system. The capacity planning is based on many factors which are classified as Cassandra specific and Product specific.This study is to identify the different Cassandra specific and product specific factors affecting the disk space in Cassandra data storage system. Based on these factors a model is to be built which would predict the disk storage for Ericsson’s voucher system.A case-study is conducted on Ericsson’s voucher system and its Cassandra cluster. Interviews were conducted on different Cassandra users within Ericsson R&D to know their opinion on capacity planning approaches and factors affecting disk space for Cassandra. Responses from the interviews were transcribed and analyzed using grounded theory.A total of 9 Cassandra specific factors and 3 product specific factors are identified and documented. Using these 12 factors a model was built. This model was used in predicting the disk space required for voucher system’s Cassandra.The factors affecting disk space for deploying Cassandra are now exhaustively identified. This makes the capacity planning process more efficient. Using these factors the Voucher system’s disk space for deployment is predicted successfully.

  • 85. Abd El Ghany, M. A.
    et al.
    El-Moursy, M. A.
    Ismail, Mohammed
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. Ohio State University, Columbus, United States .
    High throughput architecture for high performance NoC2009In: ISCAS: 2009 IEEE International Symposium on Circuits and Systems, IEEE , 2009, p. 2241-2244Conference paper (Refereed)
    Abstract [en]

    High Throughput Butterfly Fat Tree (HTBFT) architecture to achieve high performance Networks on Chip (NoC) is proposed. The architecture increases the throughput of the network by 38% while preserving the average latency. The area of HTBFT switch is decreased by 18% as compared to Butterfly Fat Tree switch. The total metal resources required to implement HTBFT design is increased by 5% as compared to the total metal resources required to implement BFT design. The extra power consumption required to achieve the proposed architecture is 3% of the total power consumption of the BFT architecture.

  • 86.
    ABDALMAHMOODABADI, MAHBOOBEH
    KTH, School of Information and Communication Technology (ICT).
    The value of downstream information sharing in two-level supply chain: AN APPROACH TO AGENT-BASED MODELING2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Many supply chain firms have taken initiatives to facilitate demand information sharing between downstream and upstream entities. Information sharing is a key factor of collaboration in supply chain management (SCM). In the last decades, many efforts have been made to model supply chain mathematically. Mathematical models are incapable of capturing the dynamic nature of the system. It is necessary to study multidimensional supply chain model in which not only there is communication between supplier and retailer but also communication among retailers must be considered. Mathematical models can be seen as a simple decision making optimization between two entities in which the effect of cooperation of other entities is completely ignored. These models are far from real world systems. The purpose of this thesis is to create an agent-based model, as a substitute to mathematical modeling, to appraise the importance of sharing information on supplier side when there is relation among retailers by means of stock sharing. The conceptual model of two-echelon supply chain is designed and implemented in Java using Repast suit. The model includes four types of agents namely supply chain, supplier, retailer and mediator agents that interact with each other in a discrete event based simulation. Multi level factorial design is used to evaluate performance of supply chain, in terms of total cost saving, under different demand patterns. The significant difference between experimental settings is tested statistically using ANOVA, Pairwise, and Univariate tests. Data analysis indicates that the significance of information sharing can be rather high, in particular when end customers' demands are considerably correlated. Such cost saving that is achieved by sharing information is due to reducing stock level and at the expense of increasing the amount of backorder.

  • 87. Abd-Alrahman, Ahmed Mustafa
    et al.
    Ekenberg, Love
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Modelling Health Information during Catastrophic Events - A Disaster Management System for Sudan2017In: IST-Africa 2017: Conference Proceedings / [ed] Paul Cunningham, Miriam Cunningham, International Information Management Corporation Limited, 2017, p. 1-9Conference paper (Refereed)
    Abstract [en]

    There is an increasing trend of disastrous events during past decade with significant damage in terms of lives, infrastructure, economics and environment. Disastrous events are affecting communities worldwide and, apart for the actual and personal suffering involved, can fundamentally disrupt societal functions for many years. This is particularly the case in already vulnerable regions, which often require external assistance of various kinds. In order to reduce catastrophic effects of disasters, disaster mitigation measures and crisis reduction must be systematically planned and managed. This includes correct damage assessment, fast, efficient and prepared responses, adequate resource allocation and organisation of the relief processes. Obviously, the conditions and abilities to implement such measures are very different in various locations, where regions have particularly severe conditions. In this paper, we discuss crisis management in Sudan and highlight the need for national and regional disaster management processes and activities as well as general framework for the design of an efficient disaster management program in Sudan.

  • 88. Abdel Hai, R
    et al.
    Yassin, A
    Ahmad, MF
    Fors, Uno
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Comparing an e-Learning Reproductive Health Module with Traditional Lectures at a Medical School in Egypt2010In:  , 2010Conference paper (Other academic)
  • 89. Abdel Hai, R
    et al.
    Yassin, A
    Ahmad, MF
    Fors, Uno
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Exploring Knowledge, Attitudes and Behaviors of Medical Students Towards Using Computer Technology in Learning2010In:  , 2010Conference paper (Other academic)
  • 90.
    Abdelaziz, Ahmed
    et al.
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Ang, Tanfong
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Sookhak, Mehdi
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Khan, Suleman
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Liew, Cheesun
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Akhunzada, Adnan
    Faculty of Computer Science and Information Technology, University of Malaya, Kuala Lumpur.
    Survey on network virtualization using openflow: Taxonomy, opportunities, and open issues2016In: KSII Transactions on Internet and Information Systems, ISSN 1976-7277, Vol. 10, no 10, p. 4902-4932Article in journal (Refereed)
    Abstract [en]

    The popularity of network virtualization has recently regained considerable momentum because of the emergence of OpenFlow technology. It is essentially decouples a data plane from a control plane and promotes hardware programmability. Subsequently, OpenFlow facilitates the implementation of network virtualization. This study aims to provide an overview of different approaches to create a virtual network using OpenFlow technology. The paper also presents the OpenFlow components to compare conventional network architecture with OpenFlow network architecture, particularly in terms of the virtualization. A thematic OpenFlow network virtualization taxonomy is devised to categorize network virtualization approaches. Several testbeds that support OpenFlow network virtualization are discussed with case studies to show the capabilities of OpenFlow virtualization. Moreover, the advantages of popular OpenFlow controllers that are designed to enhance network virtualization is compared and analyzed. Finally, we present key research challenges that mainly focus on security, scalability, reliability, isolation, and monitoring in the OpenFlow virtual environment. Numerous potential directions to tackle the problems related to OpenFlow network virtualization are likewise discussed

  • 91. Abdelhai, Rehab
    et al.
    Yassin, Sahar
    Ahmad, Mohamad F.
    Fors, Uno
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    An e-learning reproductive health module to support improved student learning and interaction: a prospective interventional study at a medical school in Egypt2012In: BMC Medical Education, ISSN 1472-6920, E-ISSN 1472-6920, Vol. 12, p. 11-Article in journal (Refereed)
    Abstract [en]

    Background: The Public Health (PH) course at the medical college of Cairo University is based on traditional lectures. Large enrollment limits students' discussions and interactions with instructors. Aim: Evaluate students' learning outcomes as measured by improved knowledge acquisition and opinions of redesigning the Reproductive Health (RH) section of the PH course into e-learning and assessing e-course utilization. Methods: This prospective interventional study started with development of an e-learning course covering the RH section, with visual and interactive emphasis, to satisfy students' diverse learning styles. Two student groups participated in this study. The first group received traditional lecturing, while the second volunteered to enroll in the e-learning course, taking online course quizzes. Both groups answered knowledge and course evaluation questionnaires and were invited to group discussions. Additionally, the first group answered another questionnaire about reasons for non-participation. Results: Students participating in the e-learning course showed significantly better results, than those receiving traditional tutoring. Students who originally shunned the e-course expressed eagerness to access the course before the end of the academic year. Overall, students using the redesigned e-course reported better learning experiences. Conclusions: An online course with interactivities and interaction, can overcome many educational drawbacks of large enrolment classes, enhance student's learning and complement pit-falls of large enrollment traditional tutoring.

  • 92.
    Abdelmassih, Christian
    et al.
    KTH, School of Computer Science and Communication (CSC).
    Hultman, Axel
    KTH, School of Computer Science and Communication (CSC).
    Förutspå golfresultat med hjälp av sentimentanalys på Twitter2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this study we examine the relationship between the sentiment value of golf players’ tweets and their sports results to evaluate the predictive power of the their twitter accounts. Findings on this topic may be of value to bookmakers, gamblers, coaches and fans of sport. Our study is based on two datasets: PGA­tour golf statistics and 112 101 tweets made by 155 profesional golfers over the course of two seasons. The golf players’ sentiment was quantified using the lexical sentiment analysis method AFINN.

    In contrast to other research with similiar methods, our findings suggest that there is low correlation betweet the datasets and that the methods used in our study have low predictive power. Our recommendation is that future studies use additional prediction variables besides sentiment score to better evaluate the predictive power of golf players’ tweets. 

  • 93.
    Abdelraheem, Mohamed Ahmed
    et al.
    RISE, Swedish ICT, SICS.
    Alizadeh, Javad
    Alkhzaimi, Hoda A.
    Aref, Mohammad Reza
    Bagheri, Nasour
    Gauravaram, Praveen
    Improved Linear Cryptanalysis of reduced-round SIMON-32 and SIMON-482015Conference paper (Refereed)
    Abstract [en]

    In this paper we analyse two variants of SIMON family of light-weight block ciphers against linear cryptanalysis and present the best linear cryptanalytic results on these variants of reduced-round SIMON to date. We propose a time-memory trade-off method that finds differential/linear trails for any permutation allowing low Hamming weight differential/linear trails. Our method combines low Hamming weight trails found by the correlation matrix representing the target permutation with heavy Hamming weight trails found using a Mixed Integer Programming model representing the target differential/linear trail. Our method enables us to find a 17-round linear approximation for SIMON-48 which is the best current linear approximation for SIMON-48. Using only the correlation matrix method, we are able to find a 14-round linear approximation for SIMON-32 which is also the current best linear approximation for SIMON-32. The presented linear approximations allow us to mount a 23-round key recovery attack on SIMON-32 and a 24-round Key recovery attack on SIMON-48/96 which are the current best results on SIMON-32 and SIMON-48. In addition we have an attack on 24 rounds of SIMON-32 with marginal complexity.

  • 94.
    Abdelraheem, Mohamed Ahmed
    et al.
    RISE - Research Institutes of Sweden, ICT, SICS.
    Andersson, Tobias
    RISE - Research Institutes of Sweden, ICT, SICS.
    Gehrmann, Christian
    Lunds university, Sweden.
    Searchable Encrypted Relational Databases:Risks and Countermeasures2017In: Data Privacy Management, Cryptocurrencies and Blockchain Technology: ESORICS 2017 International Workshops, DPM 2017 and CBT 2017, Oslo, Norway, September 14-15, 2017, Proceedings / [ed] Joaquin Garcia-Alfaro et al., Gewerbestrasse 11, 6330 Cham, Switzerland: Springer Nature , 2017, Vol. 10436, p. 70-85Conference paper (Refereed)
    Abstract [en]

    We point out the risks of protecting relational databases viaSearchable Symmetric Encryption (SSE) schemes by proposing an infer-ence attack exploiting the structural properties of relational databases.We show that record-injection attacks mounted on relational databaseshave worse consequences than their file-injection counterparts on un-structured databases. Moreover, we discuss some techniques to reducethe effectiveness of inference attacks exploiting the access pattern leak-age existing in SSE schemes. To the best of our knowledge, this is thefirst work that investigates the security of relational databases protectedby SSE schemes.

  • 95.
    Abdelraheem, Mohamed Ahmed
    et al.
    SICS Swedish ICT AB, SWE.
    Gehrmann, Christian
    SICS Swedish ICT AB, SWE.
    Lindström, Malin
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Nordahl, Christian
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Executing Boolean queries on an encrypted Bitmap index2016In: CCSW 2016 - Proceedings of the 2016 ACM Cloud Computing Security Workshop, co-located with CCS 2016, Association for Computing Machinery (ACM), 2016, p. 11-22Conference paper (Refereed)
    Abstract [en]

    We propose a simple and efficient searchable symmetric encryption scheme based on a Bitmap index that evaluates Boolean queries. Our scheme provides a practical solution in settings where communications and computations are very constrained as it offers a suitable trade-off between privacy and performance.

  • 96.
    Abdelraheem, Mohammed Ahmed
    et al.
    RISE, Swedish ICT, SICS, Security Lab.
    Gehrmann, Christian
    RISE, Swedish ICT, SICS, Security Lab.
    Lindström, Malin
    Nordahl, Christian
    Executing Boolean Queries on an EncryptedBitmap Index2016Conference paper (Refereed)
    Abstract [en]

    We propose a simple and efficient searchable symmetric

    encryption scheme based on a Bitmap index that evaluates

    Boolean queries. Our scheme provides a practical

    solution in settings where communications and computations

    are very constrained as it offers a suitable tradeoff

    between privacy and performance.

  • 97.
    Abdelrasoul, Nader
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Optimization Techniques For an Artificial Potential Fields Racing Car Controller2013Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context. Building autonomous racing car controllers is a growing field of computer science which has been receiving great attention lately. An approach named Artificial Potential Fields (APF) is used widely as a path finding and obstacle avoidance approach in robotics and vehicle motion controlling systems. The use of APF results in a collision free path, it can also be used to achieve other goals such as overtaking and maneuverability. Objectives. The aim of this thesis is to build an autonomous racing car controller that can achieve good performance in terms of speed, time, and damage level. To fulfill our aim we need to achieve optimality in the controller choices because racing requires the highest possible performance. Also, we need to build the controller using algorithms that does not result in high computational overhead. Methods. We used Particle Swarm Optimization (PSO) in combination with APF to achieve optimal car controlling. The Open Racing Car Simulator (TORCS) was used as a testbed for the proposed controller, we have conducted two experiments with different configuration each time to test the performance of our APF- PSO controller. Results. The obtained results showed that using the APF-PSO controller resulted in good performance compared to top performing controllers. Also, the results showed that the use of PSO proved to enhance the performance compared to using APF only. High performance has been proven in the solo driving and in racing competitions, with the exception of an increased level of damage, however, the level of damage was not very high and did not result in a controller shut down. Conclusions. Based on the obtained results we have concluded that the use of PSO with APF results in high performance while taking low computational cost.

  • 98.
    Abdiu, Daniel
    et al.
    Jönköping University, Jönköping International Business School.
    Strandberg, Mikael
    Jönköping University, Jönköping International Business School.
    Stridsberg, Martin
    Jönköping University, Jönköping International Business School.
    The impact of a real-time IT-Logistics solution: Implementation effects and consequences2005Independent thesis Advanced level (degree of Magister), 10 points / 15 hpStudent thesis
    Abstract [en]

    Today’s business market is highly competitive, therefore companies need to be constantly updated and change the way they operate their business, in order to survive and remain competitive. The situation on today’s market requires that companies have the ability to quickly respond to market changes and new customer demands within short product lifecycles. In order to deal with this new market situation, companies need to improve the integration with other companies within their business. This integration facilitates the companies’ ability to quickly adapt to new market situations and survive on a fast changing market. One of the main underlying concepts of this collaborative commerce is Supply Chain Management (SCM) which integrates and coordinates a company’s processes both internally and externally. Information Technology (IT) could improve the effectiveness of SCM. IT-solutions make the business processes more effective and improves the integration with other actors within the supply chain. The purpose with this thesis is to describe and explain the effects for businesses and the consequences for its processes when implementing a real-time IT-Logistics solution together with identifying the critical success factors. The thesis has been conducted by studying theory regarding supply chain management, business renewal and implementation effects. Further, a case study has been conducted where three actors have been interviewed; a manufacturer (Volvo Powertrain), a subcontractor (Metallfabriken Ljunghäll AB) and a system developer (PipeChain). The analysis of the theoretical framework and the empirical research has contributed with an identification of major effects and consequences when implementing a real-time IT-Logistics solution. Some of the effects are: inventory reduction, higher delivery accuracy, improved relations and increased flexibility. Examples of consequences these effects have caused are: more accurate planning and production, effective production processes as well as an improved delivery process. Additionally, success factors for an implementation have been identified such as mutual trust, understanding of change and evaluation.

  • 99.
    Abdlbari, Abdulbari
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Användning av mobilapplikationer i smartphones hos unga vuxna: En fallstudie bland studenter och arbetstagare2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Nu förtiden har det blivit allt vanligare att människor använder sig av smartphones. I denna uppsats har jag kartlagt smartphone-användares användningsvanor och mönster hos unga vuxna som antingen studerar eller arbetar. För att få fram den information jag behöver har jag valt att använda mig av dagböcker där sex stycken respondenter deltog under en fyra dagars period och även intervjuer där tre av de sex respondenterna var deltagande efter genomförandet av dagböckerna. Mina resultat visar fascinerande nog att smartphones används till största del på platser där användarna är relativt stillasittande som till exempel i hemmet. Dessutom har det visat sig att studenter har en stor användning av applikationer och där med smartphones, ofta i samband med deras studier, speciellt applikationer kopplade till molntjänster.

  • 100.
    Abdlbari, Abdulbari
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Parkeringsapplikationen: Utveckling av en mobilapplikation för iPhone.2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes procedures and preparations made for developing a mobile application.Using a questionnaire and usability tests, I have developed a design document for a parkingapplication for the iPhone 4. The purpose of the application is to help drivers find allowedparking spaces thus making roads safer for everyone while the driver avoids parking tickets.

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