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  • 3051. Kawashima, Hiroaki
    et al.
    Maki, Atsuto
    Fundamental Techniques for Biometric: Feature Extraction2008In: Biometric Security Handbook, Ohmsha , 2008Chapter in book (Other academic)
  • 3052.
    Kaxiras, Stefanos
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Ros, Alberto
    A New Perspective for Efficient Virtual-Cache Coherence2013In: Proceedings of the 40th Annual International Symposium on Computer Architecture, 2013, p. 535-546Conference paper (Refereed)
    Abstract [en]

    Coherent shared virtual memory (cSVM) is highly coveted for heterogeneous architectures as it will simplify program- ming across different cores and manycore accelerators. In this context, virtual L1 caches can be used to great advan- tage, e.g., saving energy consumption by eliminating address translation for hits. Unfortunately, multicore virtual-cache coherence is complex and costly because it requires reverse translation for any coherence request directed towards a vir- tual L1. The reason is the ambiguity of the virtual address due to the possibility of synonyms. In this paper, we take a radically different approach than all prior work which is focused on reverse translation. We examine the problem from the perspective of the coherence protocol. We show that if a coherence protocol adheres to certain conditions, it operates effortlessly with virtual caches, without requir- ing reverse translations even in the presence of synonyms. We show that these conditions hold in a new class of simple and efficient request-response protocols that use both self- invalidation and self-downgrade.This results in a new solu- tion for virtual-cache coherence, significantly less complex and more efficient than prior proposals. We study design choices for TLB placement under our proposal and compare them against those under a directory-MESI protocol. Our approach allows for choices that are particularly effective as for example combining all per-core TLBs in a single logical TLB in front of the last level cache. Significant area, energy, and performance benefits ensue as a result of simplifying the entire multicore memory organization. 

  • 3053.
    Kaya, Sema Kayapinar
    et al.
    Department of Industrial Engineering, Munzur University, Tunceli, Turkey.
    Navarro-Arribas, Guillermo
    Department of Information and Communications Engineering, CYBERCAT-Center for Cybersecurity Research of Catalonia, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Torra, Vicenç
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Dynamic Features Spaces and Machine Learning: Open Problems and Synthetic Data Sets2020In: Integrated Uncertainty in Knowledge Modelling and Decision Making: 8th International Symposium, IUKM 2020, Phuket, Thailand, November 11–13, 2020, Proceedings / [ed] Van-Nam Huynh; Tomoe Entani; Chawalit Jeenanunta; Masahiro Inuiguchi; Pisal Yenradee, Springer Nature, 2020, p. 125-136Conference paper (Refereed)
    Abstract [en]

    Dynamic feature spaces appear when different records or instances in databases are defined in terms of different features. This is in contrast with usual (static) feature spaces in standard databases, where the schema of the database is known and fixed. Then, all records in the database have the same set of variables, attributes or features. Dynamic feature mining algorithms are to extract knowledge from data on dynamic feature spaces. As an example, spam detection methods have been developed from a dynamic feature space perspective. Words are taken as features and new words appearing in new emails are, therefore, considered new features. In this case, the problem of spam detection is represented as a classification problem (a supervised machine learning problem).

    The relevance of dynamic feature spaces is increasing. The large amounts of data currently available or received by systems are not necessarily described using the same feature spaces. This is the case of distributed databases with data about customers, providers, etc. Industry 4.0, Internet of Things, and RFIDs are and will be a source of data in dynamic feature spaces. New sensors added in an industrial environment, new devices connected into a smart home, new types of analysis and new types of sensors in healthcare, all are examples of dynamic feature spaces. Machine learning algorithms are needed to deal with these type of scenarios.

    In this paper we motivate the interest for dynamic feature mining, we give some examples of scenarios where these techniques are needed, we review some of the existing solutions and its relationship with other areas of machine learning and data mining (e.g., incremental learning, concept drift, topic modeling), we discuss some open problems, and we discuss synthetic data generation for this type of problem.

  • 3054.
    KAYIHAN, Ege
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Investigating Methods to Accelerate the Solving Process of Errors and Warnings Generated by Kotlin Compilers2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The efficiency of error messages that are generated from compilers is up to a debate by a lot of programmers. Some believe that by enhancing the error messages, it would be easier to handle errors faster. In this paper, the ways to enhance compiler error messages and the efficiency of the found solutions for Kotlin programming language were investigated. To do this, Kotlin programmers were interviewed about the severity of the problem and possible ways to deal with it. An example plugin project was made to describe the possible concept of solving the problem described in the compiler's error message. Afterward, the same programmers were interviewed again to discuss the efficiency and practicality of the plugin. With the last interviews being done, it was seen that this plugin idea has the potential to help the computer science society and the programmers by enhancing error and warning messages.

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  • 3055. Kazakos, K.
    et al.
    Asthana, S.
    Balaam, Madeline
    Newcastle University, Newcastle upon Tyne, United Kingdom.
    Duggal, M.
    Holden, A.
    Jamir, L.
    Kannuri, N. K.
    Kumar, S.
    Mamindla, A. R.
    Manikam, S. A.
    Murthy, G. V. S.
    Nahar, P.
    Phillimore, P.
    Sathyanath, S.
    Singh, P.
    Singh, M.
    Wright, P.
    Yadav, D.
    Olivier, P.
    A real-time IVR platform for community radio2016In: Conference on Human Factors in Computing Systems - Proceedings, 2016Conference paper (Refereed)
    Abstract [en]

    Interactive Voice Response (IVR) platforms have been widely deployed in resource-limited settings. These systems tend to afford asynchronous push interactions, and within the context of health, provide medication reminders, descriptions of symptoms and tips on self-management. Here, we present the development of an IVR system for resource-limited settings that enables real-time, synchronous interaction. Inspired by community radio, and calls for health systems that are truly local, we developed ’Sehat ki Vaani’. Sehat ki Vaani is a real-time IVR platform that enables hosting and participation in radio chat shows on community-led topics. We deployed Sehat ki Vaani with two communities in North India on topics related to the management of Type 2 diabetes and maternal health. Our deployments highlight the potential for synchronous IVR systems to offer community connection and localised sharing of experience, while also highlighting the complexity of producing, hosting and participating in radio shows in real time through IVR. We discuss the relative strengths and weaknesses of synchronous IVR systems, and highlight lessons learnt for interaction design in this area.

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  • 3056.
    Kazan, Baran
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Computer Science.
    Additional Classes Effect on Model Accuracy using Transfer Learning2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This empirical research study discusses how much the model’s accuracy changes when adding a new image class by using a pre-trained model with the same labels and measuring the precision of the previous classes to observe the changes. The purpose is to determine if using transfer learning is beneficial for users that do not have enough data to train a model. The pre-trained model that was used to create a new model was the Inception V3. It has the same labels as the eight different classes that were used to train the model. To test this model, classes of wild and non-wild animals were taken as samples. The algorithm used to train the model was implemented in a single class programmed in Python programming language with PyTorch and TensorBoard library. The Tensorboard library was used to collect and represent the result. Research results showed that the accuracy of the first two classes was 94.96% in training and 97.07% in validation. When training the model with a total of eight classes, the accuracy was 91.89% in training and 95.40 in validation. The precision of both classes was detected at 100% when the model solely had cat and dog classes. After adding six additional classes in the model, the precision changed to 95.82% of the cats and 97.16% of the dogs. 

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    BaranKazan
  • 3057.
    Kazari, Kiarash
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Network and Systems Engineering.
    Shereen, Ezzeldin
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Network and Systems Engineering.
    Dán, György
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Network and Systems Engineering.
    Decentralized Anomaly Detection in Cooperative Multi-Agent Reinforcement Learning2023In: Proceedings of the 32nd International Joint Conference on Artificial Intelligence, IJCAI 2023, International Joint Conferences on Artificial Intelligence , 2023, p. 162-170Conference paper (Refereed)
    Abstract [en]

    We consider the problem of detecting adversarial attacks against cooperative multi-agent reinforcement learning. We propose a decentralized scheme that allows agents to detect the abnormal behavior of one compromised agent. Our approach is based on a recurrent neural network (RNN) trained during cooperative learning to predict the action distribution of other agents based on local observations. The predicted distribution is used for computing a normality score for the agents, which allows the detection of the misbehavior of other agents. To explore the robustness of the proposed detection scheme, we formulate the worst-case attack against our scheme as a constrained reinforcement learning problem. We propose to compute an attack policy via optimizing the corresponding dual function using reinforcement learning. Extensive simulations on various multi-agent benchmarks show the effectiveness of the proposed detection scheme in detecting state of the art attacks and in limiting the impact of undetectable attacks.

  • 3058.
    Kazilas, Panagiotis
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Augmenting MPI Programming Process with Cognitive Computing2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cognitive Computing is a new and quickly advancing technology. In thelast decade Cognitive Computing has been used to assist researchers in theirendeavors in many different scientific fields such as Health & medicine,Education, Marketing, Psychology and Financial Services. On the otherhand, Parallel programming is a more complex concept than sequentialprogramming. The additional complexity of Parallel Programming isintroduced by its nature that requires implementations of more complexalgorithms and it introduces additional concepts to the developers, namelythe communication between the processes (Distributed memory systems)that execute the parallel program and their synchronization (Share memorysystems). As a result of this additional complexity, a lot of novice developersare reserved in their attempts to implement parallel programs. The objectiveof this research project was to investigate whether we can assist parallelprogramming process through cognitive computing solutions. In order toachieve our objective, the MPI Assistant, a Q&A system has been developedand a case study has been carried out to determine our application’s efficiencyin our attempt to assist parallel programming developers. The case studyshowed that our MPI Assistant system indeed helped developers reduce thetime they spend to develop their solutions, but not improve the quality ofthe program or its efficiency as these improvements require features that areout of this research project’s scope. However, the case study had limitednumber of participants, which may affect our results’ reliability. As a nextstep in our attempt to determine if cognitive computing technologies are ableto assist developers in their parallel programming development, we movedto investigate if cognitive solutions can extract better and more completeresponses compared to our manually-created responses that we created forthe MPI Assistant. We have experimented with 2 different approaches to theproblem. An approach where we manually created responses for the MPIAssistant, and an approach where we investigated if cognitive solutions canautomatically extract better and complete responses. We compared the qualityof the latter automatic responses with the quality of the former which weremanually created.

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    Augmenting MPI Programming Process with Cognitive Computing
  • 3059.
    K.C., Sandeep
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems.
    Platform Independent Connections to Internet of Things2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the past few years, technology has been changing by leaps and bounds, within which a new topic has emerged as Internet of Things. These things serve as sensors/actuators, connected to the Internet and enabled to communicate with each other simultaneously in a P2P distributed manner. The sensors/actuators sense and generate contextual data in their surroundings in order to enable real-time context-aware behavior that make them more personalized and intelligent. This contextual information may be useful for human purposes like environment monitoring, home surveillance, elderly care, safety, security surveillance, etc. Moreover, smart mobile devices with incredible features have become hugely popular, the use of the Internet of Things would be much handier using smartphones to interact with sensors and also to generate information with its decorated sensors. The main aim of this thesis work is to create an extension for an add-in layer of the Internet of Things (SensibleThings Platform) architecture that adds functionalities like querying UCI value within the platform, connecting different mobile devices regardless of programming language, which has been done using the REST protocol. Furthermore, the intention is to build a P2P connection between the Java coded SensibleThings platform to a non-Java platform, i.e. iOS, by creating an Objective-C library to support dissemination of contextual information between the discrete platform in a distributed manner using JSON. Two servers have been created using Apache web server and sockets to connect with the Objective-C library to compare the performance of extension and library. The thesis work also presents the implementation of the extension and an Objective-C library, integrated to create proof-of-concept applications by developing an iOS application and Mac OS desktop application that can easily interact with the SensibleThings platform by requests through the REST protocol and getting the UCI value in JSON message format. Moreover, to know the best possible solution for the SensibleThings platform, a hybrid application has also been developed by using PhoneGap and JQueryMobile within XCode, which is compared with the iOS web app, and an evaluation of mobile applications using extension and library with two servers has also been performed. According to the results between the web server and sockets, the sockets act scalable and more stable than the web server when interacting with the SensibleThings platform; when comparing between the iOS and Mac app for performance, there is not much difference. The results also suggest that a hybrid app would be a better solution for the SensibleThings platform; it could be developed with less effort and be useful for a variety of mobile devices, which might be the best solution for the IoT in the future. Lastly, the conclusions includes possible future work to be supplemented, to make the IoT better in future.

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  • 3060.
    Kebande, Victor R.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science.
    Industrial internet of things (IIoT) forensics: The forgotten concept in the race towards industry 4.02022In: Forensic Science International: Reports, ISSN 2665-9107, Vol. 5, article id 100257Article in journal (Refereed)
    Abstract [en]

    Advances in Industrial Internet of Things (IIoT), inter-connectivity, continuous rise of smart ecosystems, and the quintessential need of process automation has not only opened formidable opportunities, but it has also extended the cyber-threat and attack landscape. Predominantly, this has been witnessed even as industries race towards aligning themselves with the on-demand industry 4.0 goals. Notably, it has become apparent that the convergence and amalgamation of Industrial Operational Technology (OT) with Information Technology (IT) brings about sophiscation, IIoT ecosystem complexities, paradigm shift and overall changes in security and digital forensic investigation architectures. Consequently, as the cybersecurity threat landscape also becomes more complicated in this context, with a widened attack surface, emergent and diverse system behaviors, the digital forensic perspective of IIoT is hardly integrated or addressed as many industries race to realize industry 4.0 objectives at the time of writing this paper. It is based on this premise, that this paper puts an argument that, at the time of writing this paper, there still lacks methodologies, standards, processes or maturity models that have a focus on IIoT forensics as the rat-race towards achieving Industry 4.0 persists. Based on these dimensions, the author explores the scope of IIoT forensics and posits the need of exploring and incorporating forensic standards and methods in IIoT. It is the authors’ opinion that the suppositions fronted herewith may provide fundamental building blocks for future IIoT-centered investigative frameworks. © 2022 The Authors

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  • 3061.
    Kebande, Victor R.
    et al.
    Luleå Univ Technol, Dept Comp Sci Elect & Space Engn, S-97187 Luleå, Sweden.;Blekinge Inst Technol, Dept Comp Sci DIDA, S-37179 Karlskrona, Sweden..
    Awaysheh, Feras M.
    Tartu Univ, Inst Comp Sci, Data Syst Res Grp, EE-51009 Tartu, Estonia..
    Ikuesan, Richard A.
    Community Coll Qatar, Cyber & Network Secur Dept, Doha 00974, Qatar..
    Alawadi, Sadi
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Scientific Computing.
    Alshehri, Mohammad Dahman
    Taif Univ, Coll Comp & Informat Technol, Dept Comp Sci, POB 11099, At Taif 21944, Saudi Arabia..
    A Blockchain-Based Multi-Factor Authentication Model for a Cloud-Enabled Internet of Vehicles2021In: Sensors, E-ISSN 1424-8220, Vol. 21, no 18, article id 6018Article in journal (Refereed)
    Abstract [en]

    Continuous and emerging advances in Information and Communication Technology (ICT) have enabled Internet-of-Things (IoT)-to-Cloud applications to be induced by data pipelines and Edge Intelligence-based architectures. Advanced vehicular networks greatly benefit from these architectures due to the implicit functionalities that are focused on realizing the Internet of Vehicle (IoV) vision. However, IoV is susceptible to attacks, where adversaries can easily exploit existing vulnerabilities. Several attacks may succeed due to inadequate or ineffective authentication techniques. Hence, there is a timely need for hardening the authentication process through cutting-edge access control mechanisms. This paper proposes a Blockchain-based Multi-Factor authentication model that uses an embedded Digital Signature (MFBC_eDS) for vehicular clouds and Cloud-enabled IoV. Our proposed MFBC_eDS model consists of a scheme that integrates the Security Assertion Mark-up Language (SAML) to the Single Sign-On (SSO) capabilities for a connected edge to cloud ecosystem. MFBC_eDS draws an essential comparison with the baseline authentication scheme suggested by Karla and Sood. Based on the foundations of Karla and Sood's scheme, an embedded Probabilistic Polynomial-Time Algorithm (ePPTA) and an additional Hash function for the P-i generated during Karla and Sood's authentication were proposed and discussed. The preliminary analysis of the proposition shows that the approach is more suitable to counter major adversarial attacks in an IoV-centered environment based on the Dolev-Yao adversarial model while satisfying aspects of the Confidentiality, Integrity, and Availability (CIA) triad.

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    FULLTEXT01
  • 3062.
    Kebria, Muhammad Roohan
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Analyzing IP/MPLS as Fault Tolerant Network Architecture2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    MPLS is a widely used technology in the service providers and enterprise networks across the globe. MPLS-enabled infrastructure has the ability to transport any type of payload (ATM, Frame Relay and Ethernet) over it, subsequently providing a multipurpose architecture. An incoming packet is classified only once as it enters into the MPLS domain and gets assigned label information; thereafter all decision processes along a specified path is based upon the attached label rather than destination IP addresses. As network applications are becoming mission critical, the requirements for fault tolerant networks are increasing, as a basic requirement for carrying sensitive traffic. Fault tolerance mechanisms as provided by an IP/MPLS network helps in providing end to end “Quality of Service” within a domain, by better handling blackouts and brownouts. This thesis work reflects how MPLS increases the capability of deployed IP infrastructure to transport traffic in-between end devices with unexpected failures in place. It also focuses on how MPLS converts a packet switched network into a circuit switched network, while retaining the characteristics of packet switched technology. A new mechanism for MPLS fault tolerance is proposed.

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    IPMPLS-FaultTolerance
  • 3063.
    Kefato, Zekarias
    et al.
    Trento University.
    Sheikh, Nasrullah
    Trento University.
    Bahri, Leila
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Soliman, Amira
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Girdzijauskas, Sarunas
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Montresor, Alberto
    Trento University.
    CaTS: Network-Agnostic Virality Prediction Model to Aid Rumour Detection2018Conference paper (Refereed)
  • 3064.
    Keipour, Hossein
    et al.
    Blekinge Institute of Technology, 37179, Karlskrona, Sweden.
    Hazra, Saptarshi
    RISE Computer Science.
    Finne, Niclas
    RISE Computer Science.
    Voigt, Thiemo
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Architecture and Computer Communication. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems. RISE Computer Science.
    Generalizing Supervised Learning for Intrusion Detection in IoT Mesh Networks2021In: Ubiquitous Security: First International Conference, UbiSec 2021, Guangzhou, China, December 28–31, 2021, Revised Selected Papers, Singapore: Springer, 2021, p. 214-228Conference paper (Refereed)
    Abstract [en]

    IoT mesh networks typically consist of resource-constrained devices that communicate wirelessly. Since such networks are exposed to numerous attacks, designing intrusion detection systems is an important task and has attracted a lot of attention from the research community. Most existing work, however, has only considered a few network topologies, often also assuming a fixed number of nodes. In this paper, we generate a new large attack dataset, using Multi-Trace, a tool that we recently devised to generate traces to train machine learning algorithms. We show that using more and more diverse training data, the resulting intrusion detection models generalize better compared to those trained with less and less diverse training data. They even generalize well for larger topologies with more IoT devices. We also show that when we train different machine learning methods on our dataset, the resulting intrusion detection systems achieve very high performance.

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  • 3065.
    Kelkkanen, Viktor
    Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Implementation and Evaluation of Positional Voice Chat in a Massively Multiplayer Online Role Playing Game2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Computer games, especially Massively Multiplayer Online Role Playing Games, have elements where communication between players is of great need. This communication is generally conducted through in-game text chats, in-game voice chats or external voice programs. In-game voice chats can be constructed to work in a similar way as talking does in real life. When someone talks, anyone close enough to that person can hear what is said, with a volume depending on distance. This is called positional or spatial voice chat in games. This differs from the commonly implemented voice chat where participants in conversations are statically defined by a team or group belonging. Positional voice chat has been around for quite some time in games and it seems to be of interest for a lot of users, despite this, it is still not very common.

    This thesis investigates impacts of implementing a positional voice chat in the existing MMORPG Mortal Online by Star Vault. How is it built, what are the costs, how many users can it support and what do the users think of it? These are some of the questions answered within this project.

    The design science research method has been selected as scientific method. A product in form of a positional voice chat library has been constructed. This library has been integrated into the existing game engine and its usage has been evaluated by the game’s end users.

    Results show a positional voice system that in theory supports up to 12500 simultaneous users can be built from scratch and be patched into an existing game in less than 600 man-hours. The system needs third-party libraries for threading, audio input/output, audio compression, network communication and mathematics. All libraries used in the project are free for use in commercial products and do not demand code using them become open source.

    Based on a survey taken by more than 200 users, the product received good ratings on Quality of Experience and most users think having a positional voice chat in a game like Mortal Online is important. Results show a trend of young and less experienced users giving the highest average ratings on quality, usefulness and importance of the positional voice chat, suggesting it may be a good tool to attract new players to a game.

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  • 3066.
    Keller, Markus
    Linköping University, Department of Electrical Engineering, Computer Engineering.
    Implementation of LTE Baseband Algorithms for a Highly Parallel DSP Platform2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The division of computer engineering at Linköping’s university is currentlydeveloping an innovative parallel DSP processor architecture called ePUMA. Onepossible future purpose of the ePUMA that has been thought of is to implement itin base stations for mobile communication. In order to investigate the performanceand potential of the ePUMA as a processing unit in base stations, a model of theLTE physical layer uplink receiving chain has been simulated in Matlab and thenpartially mapped onto the ePUMA processor.The project work included research and understanding of the LTE standard andsimulating the uplink processing chain in Matlab for a transmission bandwidth of5 MHz. Major tasks of the DSP implementation included the development of a300-point FFT algorithm and a channel equalization algorithm for the SIMD unitsof the ePUMA platform. This thesis provides the reader with an introduction tothe LTE standard as well as an introduction to the ePUMA processor. Furthermore,it can serve as a guidance to develop mixed point radix FFTs in general orthe 300 point FFT in specific and can help with a basic understanding of channelequalization. The work of the thesis included the whole developing chain from understandingthe algorithms, simplifying and mapping them onto a DSP platform,and testing and verification of the results.

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  • 3067.
    Kenaudekar, Jayesh
    Linköping University, Department of Computer and Information Science, Database and information techniques.
    Anomalous Behavior Detection in Aircraft based Automatic Dependent Surveillance–Broadcast (ADS-B) system using Deep Graph Convolution and Generative model (GA-GAN)2022Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Automatic Dependent Surveillance-Broadcast (ADS-B) is a key component of the Next Generation Air Transportation System (Next Gen) that manages the increasingly congested airspace and operation. From Jan 2020, the U.S. Federal Aviation Administration (FAA) mandated the use of (ADS-B) as a key component of Next Gen project. ADS-Bprovides accurate aircraft localization via satellite navigation and efficient air traffic management, and also improves the safety of thousands of passengers travelling worldwide. While the benefits of ADS-B are well known, the fact that ADS-B is an open protocol introduces various exploitable security vulnerabilities. One practical threat is the ADS-B spoofing attack that targets the ground station, in which the ground-based attacker manipulates the International Civil Aviation Organization (ICAO) address (which is a unique identifierfor each aircraft) in the ADS-B forwarded messages to fake the appearance of non-existent aircraft or masquerade as a trusted aircraft. As a result, this type of attack can confuseand misguide the aircraft pilots or the air traffic control personnel and cause dangerous maneuvers.

    In this project, we intend to build a robust Intrusion Detection System (IDS) to detectanomalous behavior and classify attacks in an aircraft ADS-B protocol in real time duringair-ground communication. The IDS system we propose is a 3 stage deep learning framework built using Spatial Graph Convolution Networks and Deep auto-regressive generative model. In stage 1 we use a Graph convolution network architecture to classify the dataas attacked or normal in the entire airspace of an operating aircraft. In stage 2 we analyze the sequences of air-space states to identify anomalies using a generative Wavenet modeland simultaneously output feature under attack. Final stage consist of aircraft (ICAO) classification module based on unique RF transmitter signal characteristics of an aircraft. This allows the ground station operator to examine each incoming message based on the Phylayer features as well as message data field (such as, position, velocity, altitude) and flagsuspicious messages. The model is trained in a supervised fashion using federated learning where the data remains private to the data owner, i.e.: aircraft-ground station without data being explicitly sent to the cloud server. The server only receives the learned parameters for inference, there by training the entire model on the edge, thus preserving data-privacyand potential adversarial attacks. We aim to achieve a high precision real-time IDS system, with very low false alarm rate for real world deployment

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  • 3068.
    Kessler, Christoph
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Fourth Swedish Workshop on Multi-Core Computing MCC-2011: November 23-25, 2011, Linköping University, Linköping, Sweden2011Conference proceedings (editor) (Other academic)
    Abstract [en]

    MCC-2011 covers a wide variety of topics, including programming for GPU-based systems, mobile multi-core based platforms, scalable concurrent data structures, memory hierarchies, auto-tuning, transactional memory and thread-level speculation, parallel programming models, scheduling and mapping, applications, and even teaching of multicore programming.

  • 3069.
    Kessler, Christoph
    et al.
    Linköpings University.
    Dastgeer, Usman
    Linköpings University.
    Majeed, Mudassar
    Linköpings University.
    Furmento, Nathalie
    University of Bordeaux.
    Thibault, Samuel
    University of Bordeaux.
    Namyst, Raymond
    University of Bordeaux.
    Benkner, Siegfried
    University of Vienna.
    Pllana, Sabri
    University of Vienna.
    Träff, Jesper Larsson
    Vienna University of Technology.
    Wimmer, Martin
    Leveraging PEPPHER Technology for Performance Portable Supercomputing2012In: Proceedings 2012 SC Companion: High Performance Computing, Networking Storage and Analysis SC Companion 2012, 2012, p. 1395-1396Conference paper (Refereed)
    Abstract [en]

    PEPPHER is a 3-year EU FP7 project that develops a novel approach and framework to enhance performance portability and programmability of heterogeneous multi-core systems. Its primary target is single-node heterogeneous systems, where several CPU cores are supported by accelerators such as GPUs. This poster briefly surveys the PEPPHER framework for single-node systems, and elaborates on the prospectives for leveraging the PEPPHER approach to generate performance-portable code for heterogeneous multi-node systems.

  • 3070.
    Kettig, Peter
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Benchmarking of C++ image processing libraries within the Euclid project2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this report, the issue of selecting a C++ image processing library for the Euclid science ground segment (SGS) is tackled. A new benchmark is proposed to objectively compare libraries according to both static, development-related, and dynamic, execution-related criteria.

    Instead of comparing isolated functions, a much more realistic scenario is implemented: a complete processing pipeline based on a use-case algorithm, called L.A. cosmic. Already existing in the SGS and used multiple times for the flagging of galactic cosmic rays (GCRs), this algorithm is the optimal choice for setting up the benchmark. This makes the results much more usable than with classical single- function benchmarks.

    First, the used tools as well as both categories are explained with their respective criteria listed, all tailored to the needs of the SGS. This also introduces the statistical profiling used throughout the project. Additionally, a scientific validation is introduced that monitors the accuracy of the implementations created.

    Afterwards, the benchmark is conducted and the results are presented and discussed. Indeed, including static criteria helps taking into account development and debugging time – key elements of the project life. Moreover, most library contenders are lacking important functions required for the implementation of the reference algorithm and are therefore excluded from further measurements. Documenting the missing or unclear functions gives then an overview about how user-friendly a library is to develop with.

    The scientific validation depicts that a missing function in one of the contenders and the resulting deviation from the reference results in a lower accuracy. Leaving out the problematic part of the pipeline improves the results, yet only with a higher amount of stars being misinterpreted as GCRs.

    The dynamic criteria report that all contenders perform better than a python reference version as well as a consistent linear dependency to the input image size, while also offering an approach to multi-core processing. Yet, the latter exhibits problems of some libraries to scale appropriately with more resources, leaving the results divided between the single- and multi-core setups for this benchmark.

    When taking this parameter of cores into account, the benchmark allows to recommend the most appropriate library to the SGS. 

  • 3071.
    Khadgi, Vinaya
    et al.
    Jönköping University, School of Engineering, JTH. Research area Information Engineering.
    Wang, Tianyi
    Jönköping University, School of Engineering, JTH. Research area Information Engineering.
    Automatic Creation of Researcher’s Competence Profiles Based on Semantic Integration of Heterogeneous Data sources2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The research journals and publications are great source of knowledge produced by the virtue of hard work done by researchers. Several digital libraries have been maintaining the records of such research publications in order for general people and other researchers to find and study the previous work done in the research field they are interested in. In order to make the search criteria effective and easier, all of these digital libraries keep a record/database to store the meta-data of the publications. These meta-data records are generally well design to keep the vital records of the publications/articles, which has the potential to give information about the researcher, their research activities, and hence the competence profile.

    This thesis work is a study and search of method for building the competence profile of researchers’ base on the records of their publications in the well-known digital libraries. The publications of researchers publish in different publication houses, so, in order to make a complete profile, the data from several of these heterogeneous digital libraries sources have to be integrated semantically. Several of the semantic technologies were studied in order to investigate the challenges of integration of the heterogeneous sources and modeling the researchers’ competence profile .An approach of on-demand profile creation was chosen where user of system could enter some basic name detail of the researcher whose profile is to be created. In this thesis work, Design Science Research methodology was used as the method for research work and to complement this research method with a working artifact, scrum- an agile software development methodology was used to develop a competence profile system as proof of concept. 

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  • 3072.
    Khakpour, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science. Leiden University, The Netherlands.
    Arbab, Farhad
    Leiden University, The Netherlands ; CWI, The Netherlands.
    Rutten, Eric
    INRIA, France.
    Synthesizing structural and behavioral control for reconfigurations in component-based systems2016In: Formal Aspects of Computing, ISSN 0934-5043, E-ISSN 1433-299X, Vol. 28, no 1, p. 21-43Article in journal (Refereed)
    Abstract [en]

    Correctness of the behavior of an adaptive system during dynamic adaptation is an important challenge to realize correct adaptive systems. Dynamic adaptation refers to changes to both the functionality of the computational entities that comprise a composite system, as well as the structure of their interconnections, in response to variations in the environment, e.g., the load of requests on a server system. In this research, we view the problem of correct structural adaptation as a supervisory control problem and synthesize a reconfiguration controller that guides the behavior of a system during adaptation. The reconfiguration controller observes the system behavior during an adaptation and controls the system behavior by allowing/disallowing actions in a way to ensure that a given property is satisfied and a deadlock is avoided. The system during adaptation is modeled using a graph transition system and properties to be enforced are specified using a graph automaton. We adapt a classical theory of supervisory control for synthesizing a controller for controlling the behavior of a system modeled using graph transition systems. This theory is used to synthesize a controller that can impose both behavioral and structural constraints on the system during an adaptation. We apply a tool that we have implemented to support our approach on a case study involving https servers.

  • 3073.
    Khakpour, Narges
    et al.
    Linnaeus University, Faculty of Technology, Department of Computer Science.
    Mousavi, Mohammad Reza
    Halmstad University.
    Notions of Conformance Testing for Cyber-Physical Systems: Overview and Roadmap2015In: 26th International Conference on Concurrency Theory (CONCUR 2015) / [ed] Luca Aceto, David de Frutos Escrig, Schloss Dagstuhl--Leibniz-Zentrum fuer Informatik , 2015, p. 18-40Conference paper (Refereed)
    Abstract [en]

    We review and compare three notions of conformance testing for cyber-physical systems. We begin with a review of their underlying semantic models and present conformance-preserving translations between them. We identify the differences in the underlying semantic models and the various design decisions that lead to these substantially different notions of conformance testing. Learning from this exercise, we reflect upon the challenges in designing an "ideal" notion of conformance for cyber-physical systems and sketch a roadmap of future research in this domain.

  • 3074.
    Khalilzad, Nima
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Adaptive Hierarchical Scheduling Framework for Real-Time Systems2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern computer systems are often designed to play a multipurpose role. Therefore, they are capable of running a number of software tasks (software programs) simultaneously in parallel. These software tasks should share the processor such that all of them run and finish their computations as expected. On the other hand, a number of software tasks have timing requirements meaning that they should not only access the processing unit, but this access should also be in a timely manner. Thus, there is a need to timely share the processor among different software programs (applications). The time-sharing often is realized by assigning a fixed and predefined processor time-portion to each application. However, there exists a group of applications where, i) their processor demand is changing in a wide range during run-time, and/or ii) their occasional timing violations can be tolerated. For systems that contain applications with the two aforementioned properties, it is not efficient to assign the applications with fixed processor time-portions. Because, if we allocate the processor resource based on the maximum resource demand of the applications, then the processor's computing capacity will be wasted during the time intervals where the applications will require a smaller portion than maximum resource demand. To this end, in this thesis we propose adaptive processor time-portion assignments. In our adaptive scheme, at each point in time, we monitor the actual demand of the applications, and we provide sufficient processor time-portions for each application. In doing so, we are able to integrate more applications on a shared and resource constrained system, while at the same time providing the applications with timing guarantees.

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  • 3075.
    Khalilzad, Nima
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Faragardi, Hamid Reza
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Nolte, Thomas
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Towards Energy-Aware Placement of Real-Time Virtual Machines in a Cloud Data Center2015In: Proceedings - 2015 IEEE 17th International Conference on High Performance Computing and Communications, 2015 IEEE 7th International Symposium on Cyberspace Safety and Security and 2015 IEEE 12th International Conference on Embedded Software and Systems, HPCC-CSS-ICESS 2015, 2015, p. 1657-1662Conference paper (Refereed)
    Abstract [en]

    Cloud computing is an evolving paradigm which is becoming an adoptable technology for a variety of applications. However, cloud infrastructures must be able to fulfill application requirements before adopting cloud solutions. Cloud infrastructure providers communicate the characteristics of their services to their customers through Service Level Agreements (SLA). In order for a real-time application to be able to use cloud technology, cloud infrastructure providers have to be able to provide timing guarantees in the SLAs. In this paper, we present our ongoing work regarding a cloud solution in which periodic tasks are provided as a service in the Software as a Service (SaS) model. Tasks belonging to a certain application are mapped in a Virtual Machine (VM). We also study the problem of VMplacement on a cloud infrastructure. We propose a placement mechanism which minimizes the energy consumption of the data center by consolidating VMs in a minimum number of servers while respecting the timing requirement of virtual machines.

  • 3076.
    Khamdamov, Ulugbek
    et al.
    Gwangju Institute of Science and Technology, Korea.
    Usman, Muhammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kim, JongWon
    Gwangju Institute of Science and Technology, Korea.
    A Cost-effective High-throughput Testbed for Supporting AI-enabled DevSecOps Services2023In: 10th International Conference on Future Internet of Things and Cloud (FiCloud), Institute of Electrical and Electronics Engineers (IEEE), 2023, p. 95-102Conference paper (Refereed)
    Abstract [en]

    OF@TEIN Playground is a multi-site cloud with distributed edge nodes, which, while offering reduced application latency by processing data at the edge of the network, also introduces new security challenges. To ensure the continuous and secure operation of these nodes, the SmartX Multi-View Visibility and SmartX MultiSec frameworks were introduced. However, these frameworks have limitations regarding AI-powered security mechanisms. The recent surge in data and AI technologies has amplified the need for AI-based and data-driven smart services that can process large amounts of real-time data and provide actionable insights to users. In particular, AI-inspired DevSecOps services can be highly effective in enhancing cybersecurity of the OF@TEIN Playground. However, developing and deploying these services at scale can be a challenge, due to the high costs associated with procuring and maintaining the necessary hardware and software resources. Therefore, this work aims to upgrade the OF@TEIN Playground to flexibly support cloud based AI-inspired DevSecOps services and to adequately meet the current and future demands of playground users. The results show that our effort has resulted in a more reliable, cost-effective, and flexible edge computing research and experimentation testbed.

  • 3077.
    Khamespanah, E.
    et al.
    School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran.
    Sirjani, Marjan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. School of Computer Science, Reykjavik University, Reykjavik, Iceland.
    Khosravi, R.
    School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran.
    Afra: An Eclipse-Based Tool with Extensible Architecture for Modeling and Model Checking of Rebeca Family Models2023In: Lect. Notes Comput. Sci., Springer Science and Business Media Deutschland GmbH , 2023, p. 72-87Conference paper (Refereed)
    Abstract [en]

    Afra is an Eclipse-based tool for the modeling and model checking of Rebeca family models. Together with the standard enriched editor, easy to trace counter-example viewer, modular temporal property definition, exporting a model and its transition system to some other formats facilities are features of Afra. Rebeca family provides actor-based modeling languages which are designed to bridge the gap between formal methods and software engineering. Faithfulness to the system being modeled, and the usability of Rebeca family languages help in ease of modeling and analysis of the model, together with the synthesis of the system based on the model. In this paper, architectural decisions and design strategies we made in the development of Afra are presented. This makes Afra an extensible and reusable application for the modeling and analysis of Rebeca family models. Here, we show how different compilers can be developed for the family of languages which are the same in general language constructs but have some minor differences. Then we show how the model checking engine for these different languages is designed. Despite the fact that Afra has a layered object-oriented design and is developed in Java technology, we use C++ codes for developing its model checking for the performance purposes. This decision made the design of the application even harder.

  • 3078.
    Khamespanah, Ehsan
    et al.
    Reykjavik University, Iceland.
    Mechitov, Kirill
    University of Illinois at Urbana-ChampaignChampaign, USA.
    Sirjani, Marjan
    Reykjavik University, Iceland.
    Agha, Gul
    University of Illinois at Urbana-ChampaignChampaign, USA.
    Schedulability Analysis of Distributed Real-Time Sensor Network Applications Using Actor-Based Model Checking2016In: Model Checking Software - 23rd International Symposium SPIN 2016, 2016, Vol. 9641, p. 165-181Conference paper (Refereed)
    Abstract [en]

    Programmers often use informal worst-case analysis and debugging to ensure schedules that satisfy real-time requirements. Not only can this process be tedious and error-prone, it is inherently conservative and thus likely to lead to an inefficient use of resources. We propose to use model checking to find a schedule which optimizes the use of resources while satisfying real-time requirements. Specifically, we represent a Wireless sensor and actuator network (WSAN) as a collection of actors whose behavior is specified using a C-based actor language extended with operators for real-time scheduling and delay representation. We show how the abstraction and compositionality properties of the actor model may be used to incrementally build a model of a WSAN’s behavior from node-level and network models. We demonstrate the approach with a case study of a distributed real-time data acquisition system for high frequency sensing using Timed Rebeca modeling language and the Afra model checking tool.

  • 3079.
    Khamespanah, Ehsan
    et al.
    University of Tehran, Tehran, Iran.
    Mohaqeqi, Morteza
    Uppsala University, Uppsala, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Sirjani, Marjan
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Schedulability Analysis of WSAN Applications: Outperformance of a Model Checking Approach2022In: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, Institute of Electrical and Electronics Engineers Inc. , 2022, Vol. 2022-SeptemberConference paper (Refereed)
    Abstract [en]

    Wireless sensor and actuator networks (WSAN) are real-time systems which demand timing requirements. To ensure this level of requirements, different timing analysis approaches have been proposed for WSAN systems. Among different alternatives, analytical analysis and model checking approaches are two common ones which are widely used for the timing analysis of WSAN systems. Analytical approaches apply worst-case response time analysis techniques, whereas model checking generates explicit states of models to analyze them. In this paper, we develop schedulability analysis techniques based on two approaches, i.e., analytical and model checking approaches. We apply and compare the proposed analysis approaches on WSAN systems with an application in monitoring and control of civil infrastructures implemented on the Imote2 wireless sensor platform. We show that the highest possible data acquisition frequency for this application is computed while meeting the deadlines, and compare the results of the two approaches in terms of scalability, extensibility, and flexibility.

  • 3080.
    Khamespanah, Ehsan
    et al.
    Reykjavik University, Iceland.
    Sirjani, Marjan
    Reykjavik University, Iceland.
    Mousavi, Mohammad Reza
    Halmstad University, Sweden.
    Sabahi-Kaviani, Zeynab
    University of Tehran, Iran.
    Razzazi, Mohamadreza
    Amirkabir University of Technology, Iran.
    State Distribution Policy for Distributed Model Checking of Actor Models2015In: Electronic Communications of the EASST, E-ISSN 1863-2122, Vol. 72, p. 1-16Article in journal (Refereed)
  • 3081.
    Khan, Ahmad Salman
    et al.
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Kajko-Mattsson, Mira
    KTH, School of Information and Communication Technology (ICT), Software and Computer systems, SCS.
    Evaluating and Acting on Handover Framework in a special case of Project ParkingIn: Journal of Software Maintenance and Evolution, ISSN 1532-0618Article in journal (Other academic)
    Abstract [en]

    A well-defined handover process model is imperative and critical for succeeding with the transfer of a software system from one party to another. Despite this, there still do not exist any up-to date handover process models. Recently, however, we have developed EM3: Handover Framework aiding organizations in constructing their own handover process models. In this paper, we apply and evaluate EM3: Handover Framework in one Swedish software organization via participatory observation. Our goal is to examine the framework’s applicability and usefulness in a real-world industrial scenario. The handover process studied was of a self-to-self type and it was conducted in a project parking context. Our results show that our framework is fully applicable in an industrial handover setting. Almost all of its activities were relevant and fully applied in the context studied. 

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  • 3082.
    Khan, Akif Quddus
    et al.
    Norwegian University of Science and Technology, Norway.
    Nikolov, Nikolay
    SINTEF Digital, Norway.
    Matskin, Mihhail
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Prodan, Radu
    University of Klagenfurt, Austria.
    Bussler, Christoph
    Robert Bosch LLC, CA, USA.
    Roman, Dumitru
    SINTEF Digital, Norway.
    Soylu, Ahmet
    OsloMet - Oslo Metropolitan University, Norway.
    Towards Graph-based Cloud Cost Modelling and Optimisation2023In: Proceedings: 2023 IEEE 47th Annual Computers, Software, and Applications Conference, COMPSAC 2023, Institute of Electrical and Electronics Engineers (IEEE) , 2023, p. 1337-1342Conference paper (Refereed)
    Abstract [en]

    Cloud computing has become an increasingly popular choice for businesses and individuals due to its flexibility, scalability, and convenience; however, the rising cost of cloud resources has become a significant concern for many. The pay-per-use model used in cloud computing means that costs can accumulate quickly, and the lack of visibility and control can result in unexpected expenses. The cost structure becomes even more complicated when dealing with hybrid or multi-cloud environments. For businesses, the cost of cloud computing can be a significant portion of their IT budget, and any savings can lead to better financial stability and competitiveness. In this respect, it is essential to manage cloud costs effectively. This requires a deep understanding of current resource utilization, forecasting future needs, and optimising resource utilization to control costs. To address this challenge, new tools and techniques are being developed to provide more visibility and control over cloud computing costs. In this respect, this paper explores a graph-based solution for modelling cost elements and cloud resources and potential ways to solve the resulting constraint problem of cost optimisation. We primarily consider utilization, cost, performance, and availability in this context. Such an approach will eventually help organizations make informed decisions about cloud resource placement and manage the costs of software applications and data workflows deployed in single, hybrid, or multi-cloud environments.

  • 3083.
    Khan, Amin M.
    et al.
    UiT Arctic Univ Norway, Dept Comp Sci, Tromso, Norway.;Hitachi Vantara Corp, Lisbon, Portugal..
    Freitag, Felix
    Univ Politecn Cataluna, Dept Comp Architecture, Barcelona, Spain..
    Vlassov, Vladimir
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Software and Computer systems, SCS.
    Ha, Phuong Hoai
    Demo Abstract: Towards IoT Service Deployments on Edge Community Network Microclouds2018In: IEEE INFOCOM 2018 - IEEE CONFERENCE ON COMPUTER COMMUNICATIONS WORKSHOPS (INFOCOM WKSHPS), IEEE , 2018Conference paper (Refereed)
    Abstract [en]

    Internet of Things (IoT) services for personal devices and smart homes provided by commercial solutions are typically proprietary and closed. These services provide little control to the end users, for instance to take ownership of their data and enabling services, which hinders these solutions' wider acceptance. In this demo paper, we argue for an approach to deploy professional IoT services on user-controlled infrastructure at the network edge. The users would benefit from the ability to choose the most suitable service from different IoT service offerings, like the one which satisfies their privacy requirements, and third-party service providers could offer more tailored IoT services at customer premises. We conduct the demonstration on microclouds, which have been built with the Cloudy platform in the Guifi. net community network. The demonstration is conducted from the perspective of end users, who wish to deploy professional IoT data management and analytics services in volunteer microclouds.

  • 3084. Khan, Basit
    et al.
    Matskin, Mihhail
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture, Software and Computer Systems, SCS.
    Multiagent system to support Place/Space based mobile learning in city2011In: International Conference on Information Society, i-Society 2011, 2011, p. 66-71Conference paper (Refereed)
    Abstract [en]

    Different approaches have been developed to provide technical support for mobile learning. Most these approaches consider only the physical properties of learning environment. In this work, we not only focus on the physical/spatial dimension of the learning environment of the city, but also pay attention to the notion of Place which is a meaningful outcome of peoples understanding of Space. This paper illustrates how a theoretical conceptualization of Spaces and Places is mapped into a multiagent framework called AGORA. It presents the design aspects of a mobile learning system, which uses software agents as its core functional units. We discuss how the theoretical concepts are used to define a technical solution to support mobile learning in a citywide context.

  • 3085.
    Khan, Basit
    et al.
    Norwegian University of Science and Technology (NTNU), Norway.
    Matskin, Mihhail
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture, Software and Computer Systems, SCS. Norwegian University of Science and Technology (NTNU), Norway.
    Rossitto, Chiara
    Stockholm University, Sweden.
    Towards a Places and Spaces based city-wide mobile learning through multi-agent support2011In: Digital Ecosystems and Technologies Conference (DEST), 2011 Proceedings of the 5th IEEE International Conference on / [ed] Farookh Khadeer, Hussain,Chang, Elizabeth, IEEE , 2011, p. 164-169Conference paper (Refereed)
    Abstract [en]

    This paper illustrates how the conceptualization of Places can be used to inform the technical design of mobile learning system. We apply the concept of Place in a multi-agent framework for supporting informal city-wide mobile learning activities. By taking input from the theoretical framework for analysing collaborative learning activities, we adopt the structure and organization of multi-gent framework. The functionality and components of the system are defined in light of the theoretical work. This work bridges the gap between theory and it's application in technology for mobile learning in our project.

  • 3086.
    Khan, Fahad Shahbaz
    et al.
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    Rao, Muhammad Anwer
    Department of Information and Computer Science, Aalto University School of Science, Aalto, Finland.
    van de Weijer, Joost
    Computer Vision Center, CS Department, Universitet Autonoma de Barcelona, Barcelona, Spain.
    Felsberg, Michael
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Faculty of Science & Engineering.
    Laaksonen, Jorma
    Department of Information and Computer Science, Aalto University School of Science, Aalto, Finland.
    Deep Semantic Pyramids for Human Attributes and Action Recognition2015In: Image Analysis: 19th Scandinavian Conference, SCIA 2015, Copenhagen, Denmark, June 15-17, 2015. Proceedings / [ed] Paulsen, Rasmus R., Pedersen, Kim S., Springer, 2015, Vol. 9127, p. 341-353Conference paper (Refereed)
    Abstract [en]

    Describing persons and their actions is a challenging problem due to variations in pose, scale and viewpoint in real-world images. Recently, semantic pyramids approach [1] for pose normalization has shown to provide excellent results for gender and action recognition. The performance of semantic pyramids approach relies on robust image description and is therefore limited due to the use of shallow local features. In the context of object recognition [2] and object detection [3], convolutional neural networks (CNNs) or deep features have shown to improve the performance over the conventional shallow features.

    We propose deep semantic pyramids for human attributes and action recognition. The method works by constructing spatial pyramids based on CNNs of different part locations. These pyramids are then combined to obtain a single semantic representation. We validate our approach on the Berkeley and 27 Human Attributes datasets for attributes classification. For action recognition, we perform experiments on two challenging datasets: Willow and PASCAL VOC 2010. The proposed deep semantic pyramids provide a significant gain of 17.2%, 13.9%, 24.3% and 22.6% compared to the standard shallow semantic pyramids on Berkeley, 27 Human Attributes, Willow and PASCAL VOC 2010 datasets respectively. Our results also show that deep semantic pyramids outperform conventional CNNs based on the full bounding box of the person. Finally, we compare our approach with state-of-the-art methods and show a gain in performance compared to best methods in literature.

  • 3087.
    Khan, Izhar Ahmed
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    A Distributed Context Simulation Component2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Mobile devices with access to large numbers of sensors with internet access move forwards the development of intelligent applications towards new shape of ubiquitous applications. In order to create such applications we need to be able to do simulations to test and deploy. Current simulators do not permit this since they are centralized and the information is not shared globally. Therefore we cannot use them to test application built on distributed sensor information. I selected Siafu as the simulator component. In the next step, the simulator was customized according to the requirements of the project. There are different possibilities to achieve this task, but a simple GUI is made to control the simulator.The end result is a complete architecture for simulating context aware scenarios. The implementation is tested by running the simulator and dumping the context data into the PGRID overlay. For future work, implementing proximity estimation between the agents will be a good idea and can be interesting as well.

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  • 3088.
    Khan, Mohd. Tasleem
    et al.
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Alhartomi, Mohammed A.
    Univ Tabuk, Saudi Arabia.
    Alzahrani, Saeed
    Univ Tabuk, Saudi Arabia.
    Shaik, Rafi Ahamed
    Indian Inst Technol Guwahati, India.
    Alsulami, Ruwaybih
    Umm Al Qura Univ, Saudi Arabia.
    Two Distributed Arithmetic Based High Throughput Architectures of Non-Pipelined LMS Adaptive Filters2022In: IEEE Access, E-ISSN 2169-3536, Vol. 10, p. 76693-76706Article in journal (Refereed)
    Abstract [en]

    Distributed arithmetic (DA) is an efficient look-up table (LUT) based approach. The throughput of DA based implementation is limited by the LUT size. This paper presents two high-throughput architectures (Type I and II) of non-pipelined DA based least-mean-square (LMS) adaptive filters (ADFs) using twos complement (TC) and offset-binary coding (OBC) respectively. We formulate the LMS algorithm using the steepest descent approach with possible extension to its power-normalized LMS version and followed by its convergence properties. The coefficient update equation of LMS algorithm is then transformed via TC DA and OBC DA to design and develop non-pipelined architectures of ADFs. The proposed structures employ the LUT pre-decomposition technique to increase the throughput performance. It enables the same mapping scheme for concurrent update of the decomposed LUTs. An efficient fixed-point quantization model for the evaluation of proposed structures from a realistic point-of-view is also presented. It is found that Type II structure provides higher throughput than Type I structure at the expense of slow convergence rate with almost the same steady-state mean square error. Unlike existing non-pipelined LMS ADFs, the proposed structures offer very high throughput performance, especially with large order DA base units. Furthermore, they are capable of performing less number of additions in every filter cycle. Based on the simulation results, it is found that 256th order filter with 8th order DA base unit using Type I structure provides 9 :41 x higher throughput while Type II structure provides 16 :68 x higher throughput as compared to the best existing design. Synthesis results show that 32nd order filter with 8th order DA base unit using Type I structure achieves 38 :76% less minimum sampling period (MSP), occupies 28 :62% more area, consumes 67 :18% more power, utilizes 49 :06% more slice LUTs and 3 :31% more flip-flops (FFs), whereas Type II structure achieves 51 :25% less MSP, occupies 21 :42% more area, consumes 47 :84% more power, utilizes 29 :10% more slice LUTs and 1 :47% fewer FFs as compared to the best existing design.

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  • 3089.
    Khan, Muhammad Sikandar Lal
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Presence through actions: theories, concepts, and implementations2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    During face-to-face meetings, humans use multimodal information, including verbal information, visual information, body language, facial expressions, and other non-verbal gestures. In contrast, during computer-mediated-communication (CMC), humans rely either on mono-modal information such as text-only, voice-only, or video-only or on bi-modal information by using audiovisual modalities such as video teleconferencing. Psychologically, the difference between the two lies in the level of the subjective experience of presence, where people perceive a reduced feeling of presence in the case of CMC. Despite the current advancements in CMC, it is still far from face-to-face communication, especially in terms of the experience of presence.

    This thesis aims to introduce new concepts, theories, and technologies for presence design where the core is actions for creating presence. Thus, the contribution of the thesis can be divided into a technical contribution and a knowledge contribution. Technically, this thesis details novel technologies for improving presence experience during mediated communication (video teleconferencing). The proposed technologies include action robots (including a telepresence mechatronic robot (TEBoT) and a face robot), embodied control techniques (head orientation modeling and virtual reality headset based collaboration), and face reconstruction/retrieval algorithms. The introduced technologies enable action possibilities and embodied interactions that improve the presence experience between the distantly located participants. The novel setups were put into real experimental scenarios, and the well-known social, spatial, and gaze related problems were analyzed.

    The developed technologies and the results of the experiments led to the knowledge contribution of this thesis. In terms of knowledge contribution, this thesis presents a more general theoretical conceptual framework for mediated communication technologies. This conceptual framework can guide telepresence researchers toward the development of appropriate technologies for mediated communication applications. Furthermore, this thesis also presents a novel strong concept – presence through actions - that brings in philosophical understandings for developing presence- related technologies. The strong concept - presence through actions is an intermediate-level knowledge that proposes a new way of creating and developing future 'presence artifacts'. Presence- through actions is an action-oriented phenomenological approach to presence that differs from traditional immersive presence approaches that are based (implicitly) on rationalist, internalist views.

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  • 3090.
    Khan, Muhammad Sikandar Lal
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Halawani, Alaa
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Computer Engineering Department, Palestine Polytechnic University, Hebron 90100, Palestine.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Li, Haibo
    Action Augmented Real Virtuality Design for Presence2018In: IEEE Transactions on Cognitive and Developmental Systems, ISSN 2379-8920, Vol. 10, no 4, p. 961-972Article in journal (Refereed)
    Abstract [en]

    This paper addresses the important question of how to design a video teleconferencing setup to increase the experience of spatial and social presence. Traditional video teleconferencing setups are lacking in presenting the nonverbal behaviors that humans express in face-to-face communication, which results in decrease in presence-experience. In order to address this issue, we first present a conceptual framework of presence for video teleconferencing. We introduce a modern presence concept called real virtuality and propose a new way of achieving this based on body or artifact actions to increase the feeling of presence, and we named this concept presence through actions. Using this new concept, we present the design of a novel action-augmented real virtuality prototype that considers the challenges related to the design of an action prototype, action embodiment, and face representation. Our action prototype is a telepresence mechatronic robot (TEBoT), and action embodiment is through a head-mounted display (HMD). The face representation solves the problem of face occlusion introduced by the HMD. The novel combination of HMD, TEBoT, and face representation algorithm has been tested in a real video teleconferencing scenario for its ability to solve the challenges related to spatial and social presence. We have performed a user study where the invited participants were requested to experience our novel setup and to compare it with a traditional video teleconferencing setup. The results show that the action capabilities not only increase the feeling of spatial presence but also increase the feeling of social presence of a remote person among local collaborators.

  • 3091.
    Khan, Muhammad Sikandar Lal
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. University of East London, United Kingdom.
    Mi, Yongcui
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Naeem, Usman
    University of East London, United Kingdom.
    Beskow, Jonas
    The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Li, Haibo
    The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Moveable facial features in a Social Mediator2017In: Intelligent Virtual Agents: IVA 2017 / [ed] Beskow J., Peters C., Castellano G., O'Sullivan C., Leite I., Kopp S., Springer London, 2017, p. 205-208Conference paper (Refereed)
    Abstract [en]

    A brief display of facial features based behavior has a majorimpact on personality perception in human-human communications.Creating such personality traits and representations in a social robot isa challenging task. In this paper, we propose an approach for a roboticface presentation based on moveable 2D facial features and present acomparative study when a synthesized face is projected using three setups;1) 3D mask, 2) 2D screen, and 3) our 2D moveable facial featurebased visualization. We found that robot’s personality and character ishighly influenced by the projected face quality as well as the motion offacial features.

  • 3092.
    Khan, Muhammad Sikandar Lal
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ur Réhman, Shafiq
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. University of East London, London, England.
    Söderström, Ulrik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Halawani, Alaa
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Li, Haibo
    Face-off: a Face Reconstruction Technique for Virtual Reality (VR) Scenarios2016In: Computer Vision: ECCV 2016 Workshops / [ed] Hua G., Jégou H., Springer, 2016, Vol. 9913, p. 490-503Conference paper (Refereed)
    Abstract [en]

    Virtual Reality (VR) headsets occlude a significant portion of human face. The real human face is required in many VR applications, for example, video teleconferencing. This paper proposes a wearable camera setup-based solution to reconstruct the real face of a person wearing VR headset. Our solution lies in the core of asymmetrical principal component analysis (aPCA). A user-specific training model is built using aPCA with full face, lips and eye region information. During testing phase, lower face region and partial eye information is used to reconstruct the wearer face. Online testing session consists of two phases, i) calibration phase and ii) reconstruction phase. In former, a small calibration step is performed to align test information with training data, while the later uses half face information to reconstruct the full face using aPCA-based trained-data. The proposed approach is validated with qualitative and quantitative analysis.

  • 3093.
    Khan, Muneeb
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Sembrant, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Hagersten, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Low Overhead Instruction-Cache Modeling Using Instruction Reuse Profiles2012In: International Symposium on Computer Architecture and High Performance Computing (SBAC-PAD'12), IEEE Computer Society , 2012, p. 260-269Conference paper (Refereed)
    Abstract [en]

    Performance loss caused by L1 instruction cache misses varies between different architectures and cache sizes. For processors employing power-efficient in-order execution with small caches, performance can be significantly affected by instruction cache misses. The growing use of low-power multi-threaded CPUs (with shared L1 caches) in general purpose computing platforms requires new efficient techniques for analyzing application instruction cache usage. Such insight can be achieved using traditional simulation technologies modeling several cache sizes, but the overhead of simulators may be prohibitive for practical optimization usage. In this paper we present a statistical method to quickly model application instruction cache performance. Most importantly we propose a very low-overhead sampling mechanism to collect runtime data from the application's instruction stream. This data is fed to the statistical model which accurately estimates the instruction cache miss ratio for the sampled execution. Our sampling method is about 10x faster than previously suggested sampling approaches, with average runtime overhead as low as 25% over native execution. The architecturally-independent data collected is used to accurately model miss ratio for several cache sizes simultaneously, with average absolute error of 0.2%. Finally, we show how our tool can be used to identify program phases with large instruction cache footprint. Such phases can then be targeted to optimize for reduced code footprint.

  • 3094.
    Khan, Saifullah
    et al.
    Carl von Ossietzky University of Oldenburg, Germany.
    Alam, Muhammad
    Xi'an Jiaotong Liverpool University, Suzhou, China.
    Fränzle, Martin
    Carl von Ossietzky University of Oldenburg, Germany.
    Muellner, Nils
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Chen, Yuanfang
    Dalian University of Technology, China.
    A Traffic Aware Segment-based Routing protocol for VANETs in urban scenarios2018In: Computers & electrical engineering, ISSN 0045-7906, E-ISSN 1879-0755, Vol. 68, p. 447-462Article in journal (Refereed)
    Abstract [en]

    Vehicular ad-hoc networks (VANETs) offer a diverse set of applications and therefore gain more and more attention from both academic and industrial communities. However, the deployment of VANETs is not very straight-forward. One challenge is highlighted by an uphill task of establishing and subsequently sustaining a robust communication. The need to obviate extra relay infrastructure in dynamically fluctuating topologies plus concurring shielding obstacles only magnifies this arduous task. In this context, information about traffic-density and about its estimated progress are valuable assets to tackle this issue. This paper proposes a novel routing protocol called Traffic Aware Segment-based Routing (TASR) protocol. The proposed protocol comprises two major parts: 1) Real-time vehicular traffic information for route selection allows for calculating the Expected Connectivity Degree (ECD) on different segments, and 2) a new forwarding method based on geographical information transfers packets from source to destination node. The new metric ECD takes vehicle densities into account, estimating the connectivity on each segment and thus the connectivity of nodes and data delivery ratio for transmitting packets. Furthermore, extensive simulations help analyzing the efficiency of TASR, indicating that it outperforms competing routing protocols.

  • 3095.
    Khan, Saifullah
    et al.
    Carl von Ossietzky Universität, Oldenburg, Germany.
    Alam, Muhammad
    Instituto de Telecomunicaçoes, University of Averio, Portugal.
    Müllner, Nils
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Fränzle, Martin
    Carl von Ossietzky Universität, Oldenburg, Germany.
    Cooperation and Network Coding based MAC Protocol for VANETs2015In: Proceedings of the 2015 IEEE Vehicular Networking Conference (VNC) VNC2015, 2015, p. 64-67Conference paper (Refereed)
    Abstract [en]

    In the last decade, cooperative communication and network coding techniques gained rising attention. Based on these techniques, this paper introduces a novel protocol called cooperation and network coding based MAC (CNCMAC) for vehicular ad-hoc networks (VANETs). It employs cooperative automatic repeat request (ARQ) and network coding techniques to enhance throughput. The CNC-MAC protocol works in two phases. In the first phase - cooperation - data is sent to relay nodes. The second phase - network coding - minimizes received packets. The performance of the CNC-MAC protocol is compared with cooperative ARQ-MAC, another common protocol in this domain. The simulation results indicate that CNC-MAC outperforms ARQ-MAC.

  • 3096.
    Khan, Suleman
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Gaba, Gurjot Singh
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Braeken, An
    Vrije Universiteit Brussel, Brussels, Belgium.
    Kumar, Pardeep
    Swansea University, Swansea, UK.
    Gurtov, Andrei
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    AKAASH: A realizable authentication, key agreement, and secure handover approach for controller-pilot data link communications2023In: International Journal of Critical Infrastructure Protection, ISSN 1874-5482, E-ISSN 2212-2087, Vol. 42, article id 100619Article in journal (Refereed)
    Abstract [en]

    Controller-Pilot Data Link Communications (CPDLC) are rapidly replacing voice-based Air Traffic Control (ATC) communications worldwide. Being digital, CPDLC is highly resilient and bandwidth efficient, which makes it the best choice for traffic-congested airports. Although CPDLC initially seems to be a perfect solution for modern-day ATC operations, it suffers from serious security issues. For instance, eavesdropping, spoofing, man-in-the-middle, message replay, impersonation attacks, etc. Cyber attacks on the aviation communication network could be hazardous, leading to fatal aircraft incidents and causing damage to individuals, service providers, and the aviation industry. Therefore, we propose a new security model called AKAASH, enabling several paramount security services, such as efficient and robust mutual authentication, key establishment, and a secure handover approach for the CPDLC-enabled aviation communication network. We implement the approach on hardware to examine the practicality of the proposed approach and verify its computational and communication efficiency and efficacy. We investigate the robustness of AKAASH through formal (proverif) and informal security analysis. The analysis reveals that the AKAASH adheres to the CPDLC standards and can easily integrate into the CPDLC framework.

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  • 3097.
    Khan, Suleman
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Kumar, Pardeep
    Swansea Univ, Wales.
    An, Breaken
    Vrije Univ Brussel VUB, Belgium.
    Gurtov, Andrei
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    POSTER: FL-Guard: A Federated Learning Based Ground-AirSecure Communication Model For Future Aviation Network2022Conference paper (Refereed)
    Abstract [en]

    L-band Digital Aeronautical Communication System (LDACS) is a newly proposed modern state-of-the-art system that will enable communication, navigation, and surveillance in the future aviation network. The current LDACS system does not prevent and detect intrusion within the LDACS domain. Therefore, it may suffer from various cyber-attacks, including spoofing, injection and many more attacks. To the best of our knowledge, this paper proposes the first federated learning-based attack detection model, called FL-Guard, for LDACS. Our proposed model exploits a federated learning environment and uses a deep neural network (DNN) to detect possible attacks on LDACS-based Air-Ground communication. FL-Guardis was simulated on a network of four aeroplanes, and the preliminary results show that the proposed model can detect attacks with 89 % accuracy.

  • 3098.
    Khan, Suleman
    et al.
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Singh Gaba, Gurjot
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    Gurtov, Andrei
    Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
    A Federated Learning Based Privacy-Preserving Intrusion Detection System For The Cpdlc2022Conference paper (Other academic)
    Abstract [en]

    The safety of the passengers and goods in airplanes depends upon a number of combined factors. An airplane's condition and the pilot's experience are pivotal, but another very crucial element is the synchronization among the pilots and the air traffic controller (ATC). The communication link between the two carries many uncertain aspects.  The aviation sector often tends to give more priority to safety rather than cybersecurity.  Although the controller-pilot data communication link (CPDLC) system has been proposed for consistent and reliable communication recently, it has some serious drawbacks. In this paper, we highlight the shortcomings of the CPDLC system from a cyber security perspective. We propose a federated learning-based privacy-preserving intrusion detection system (IDS) to protect the CPDLC from uplink and downlink cyber attacks. To ensure a realistic and viable solution, we created our own training dataset by eavesdropping on the air-ground communication at a site near Arlanda airport, Sweden. The anomaly detection model constructed through federated learning has achieved higher accuracy, precision, recall and F1 score as compared to the centrally and locally trained models, enabling higher security. Due to the lower training loss and time, the proposed approach is highly suitable for the sensitive aviation communications.

  • 3099.
    Khan, Taha
    et al.
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems. Dalarna University, Falun, Sweden.
    Nyholm, D.
    Uppsala University, Uppsala, Sweden.
    Westin, J.
    Dalarna University, Falun, Sweden.
    Dougherty, M.
    Dalarna University, Falun, Sweden.
    Corrigendum to "A computer vision framework for finger-tapping evaluation in Parkinson's disease"2015In: Artificial Intelligence in Medicine, ISSN 0933-3657, E-ISSN 1873-2860, Vol. 64, no 2Article in journal (Other academic)
  • 3100.
    Khanfar, Husni
    Mälardalen University, School of Innovation, Design and Engineering, Embedded Systems.
    Computing on-the-fly the Relevant Program Flows to a Control Dependency2021Report (Other academic)
    Abstract [en]

    Control dependence analysis is a key step in many program analysis techniques such as program slicing. The current approaches that compute control dependencies have two limitations. First, they are monolithically computed for the whole program at once. Second, these approaches do not compute the relevant program flows with the control dependency. They consider the relevant flows a slicing issue. This work extends our previous work that computes on demand the control dependencies for a particular program statement without making a comprehensive analysis. It defines new concepts in static program analysis discipline, that will be a new foundation for many future works in static program analysis. Moreover, it significantly optimizes our previous work. Finally, it presents a new approach that can compute the relevant predicates and goto statements to a particular control dependency. The contribution of this work is well-proved, and it has succeeded with hundreds of examples. However, this is the first work that claims that it can compute accurately and on demand the control dependencies with its relevant flows.

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