Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 298) Show all publications
Mitra, K., Zaslavsky, A. & Åhlund, C. (2015). Context-Aware QoE Modelling, Measurement and Prediction in Mobile Computing Systems (ed.). Paper presented at . IEEE Transactions on Mobile Computing, 14(5), 920-936
Open this publication in new window or tab >>Context-Aware QoE Modelling, Measurement and Prediction in Mobile Computing Systems
2015 (English)In: IEEE Transactions on Mobile Computing, ISSN 1536-1233, E-ISSN 1558-0660, Vol. 14, no 5, p. 920-936Article in journal (Refereed) Published
Abstract [en]

Quality of Experience (QoE) as an aggregate of Quality of Service (QoS) and human user-related metrics will be the key success factor for current and future mobile computing systems. QoE measurement and prediction are complex tasks as they may involve a large parameter space such as location, delay, jitter, packet loss and user satisfaction just to name a few. These tasks necessitate the development of practical context-aware QoE models that efficiently determine relationships between user context and QoE parameters. In this paper, we propose, develop and validate a novel decision-theoretic approach called CaQoEM for QoE modelling, measurement and prediction. We address the challenge of QoE measurement and prediction where each QoE parameter can be measured on a different scale and may involve different units of measurement. CaQoEM is context-aware and uses Bayesian networks and utility theory to measure and predict users' QoE under uncertainty. We validate CaQoEM using extensive experimentation, user studies and simulations. The results soundly demonstrate that CaQoEM correctly measures range-defined QoE using a bipolar scale. For QoE prediction, an overall accuracy of 98.93\% was achieved using 10-fold cross validation in multiple diverse network conditions such as vertical handoffs, wireless signal fading and wireless network congestion.

Keywords
QoE, Quality of Experience, Context-Awareness, context, Mobile IP, mobile computing, Bayesian Networks, Prediction, wireless networks, decision making, Decision Theory, use cases, subjective test, experimentation, Information technology - Telecommunication, Informationsteknik - Telekommunikation
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-9731 (URN)10.1109/TMC.2013.155 (DOI)000352569700004 ()2-s2.0-84926301859 (Scopus ID)865f01a9-1f24-4f6b-88a5-502fb8072562 (Local ID)865f01a9-1f24-4f6b-88a5-502fb8072562 (Archive number)865f01a9-1f24-4f6b-88a5-502fb8072562 (OAI)
Note
Validerad; 2015; Nivå 2; 20131114 (karan)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Boytsov, A. & Zaslavsky, A. (2013). Correctness Analysis and Verification of Fuzzy Situations in Situation Aware Pervasive Computing Systems (ed.). Paper presented at .
Open this publication in new window or tab >>Correctness Analysis and Verification of Fuzzy Situations in Situation Aware Pervasive Computing Systems
2013 (English)Report (Other academic)
Abstract [en]

Context awareness is one of the central features of pervasive computing systems. From pervasive computing perspective a situation can be defined as external semantic interpretation of context. Situation awareness aims to infer situations out of context. Developing situation awareness is a challenging task, which can be significantly hampered by errors during design stage. In this article we propose a novel method for verification of fuzzy situation definitions. Fuzzy logic is a powerful mechanism for reasoning in pervasive computing systems and verification of situation models is a new method of formally ensuring correctness of context awareness and situation awareness. Verification is applied at the design time to check that definitions of situations are error-free. Verification approach allows developers to rigorously specify expected relationships between situations and then formally check that definitions of situations comply with expected relationships. If an error is found, then additional task is to find counterexamples - particular context attribute values, which can cause situation awareness inconsistency. Counterexamples provide additional insight into the cause of error and help repairing situation definitions. We also discuss a method to formalize requirements, as well as propose and formally prove the novel verification algorithm for fuzzy situation models. Last, but not least, we analyze theoretical and practical complexity of the proposed solution.

Publisher
p. 30
Keywords
context awareness, situation awareness, fuzzy logic, fuzzy situation inference, situation algebra, verification, Information technology - Computer science, Informationsteknik - Datorvetenskap
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-23378 (URN)6b7a95eb-566a-441b-9b21-c887cb0b21a3 (Local ID)6b7a95eb-566a-441b-9b21-c887cb0b21a3 (Archive number)6b7a95eb-566a-441b-9b21-c887cb0b21a3 (OAI)
Note
Godkänd; 2013; 20130508 (andboy)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-06-11Bibliographically approved
Boytsov, A. & Zaslavsky, A. (2013). Formal verification of context and situation models in pervasive computing (ed.). Paper presented at . Pervasive and Mobile Computing, 9(1), 98-117
Open this publication in new window or tab >>Formal verification of context and situation models in pervasive computing
2013 (English)In: Pervasive and Mobile Computing, ISSN 1574-1192, E-ISSN 1873-1589, Vol. 9, no 1, p. 98-117Article in journal (Refereed) Published
Abstract [en]

Pervasive computing is a paradigm that focuses on availability of computer resources anytime anywhere for any application and supports non-intrusive integration of computing services into everyday life. Context awareness is the core feature of pervasive computing. High-level context awareness can be enhanced by situation awareness that represents the ability to detect and reason about the real-life situations. In this article we propose, analyze and validate the formal verification method for situation definitions and demonstrate its feasibility and efficiency. Situations are often defined manually by domain experts and are, therefore, susceptible to definition inconsistencies and possible errors, which in turn can cause situation reasoning problems. The proposed method takes as an input properties of situations and dependencies among them as well as situation definitions in terms of low-level context features, and then either formally proves that the definitions do comply with the expected properties, or provides a complete set of counterexamples — context parameters that prove situation inconsistency. Evaluation and complexity analysis of the proposed approach are also presented and discussed. Examples and evaluation results demonstrate that the proposed approach can be used to verify real-life situation definitions, and detect non-obvious errors in situation specifications.

National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-14632 (URN)10.1016/j.pmcj.2012.03.001 (DOI)000314805600007 ()2-s2.0-84873196721 (Scopus ID)e08e100b-39b2-413c-aab1-4d5198dfe8a8 (Local ID)e08e100b-39b2-413c-aab1-4d5198dfe8a8 (Archive number)e08e100b-39b2-413c-aab1-4d5198dfe8a8 (OAI)
Note
Validerad; 2013; 20120327 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Wibisono, W., Zaslavsky, A. & Ling, S. (2013). Situation-awareness and reasoning using uncertain context in mobile peer-to-peer environments (ed.). Paper presented at . International Journal of Pervasive Computing and Communications, 9(1), 52-71
Open this publication in new window or tab >>Situation-awareness and reasoning using uncertain context in mobile peer-to-peer environments
2013 (English)In: International Journal of Pervasive Computing and Communications, ISSN 1742-7371, E-ISSN 1742-738X, Vol. 9, no 1, p. 52-71Article in journal (Refereed) Published
Abstract [en]

Purpose – The recent advances of mobile computing and sensing technologies have enabled mobile devices to individually sense environment context and develop situation awareness capability. To gain a better understanding of the environment, mobile devices that are co-located can establish a mobile peer-to-peer (MP2P) environment to share their individual context information. The purpose of this paper is to propose a theoretical model for representing and reasoning about situations using uncertain context information captured by multiple devices in an MP2P environment. Design/methodology/approach – The paper proposes a generic model for reasoning about situations using uncertain context information captured by multiple devices in a MP2P environment. A data fusion technique is then integrated into the proposed model. To deal with uncertainty of context information captured by multiple independent devices, several models to estimate reliability of context information captured in the environment is proposed and developed. Findings – The proposed model has been implemented as a middleware and evaluated using data from real experiments in various scenarios and environment settings. The results of the experiments show the robust performances of the proposed model as the basis for situation reasoning in the environment. Originality/value – A novel model to represent situations and context information captured by multiple devices and to estimate reliability context information used for situation reasoning is proposed. The proposed model is then implemented as a middleware and validated using context data taken captured by multiple independent devices in a MP2P environment.

National Category
Media and Communication Technology
Identifiers
urn:nbn:se:ltu:diva-15704 (URN)10.1108/17427371311315752 (DOI)f406d3dd-867e-402e-ad3b-3daa316db155 (Local ID)f406d3dd-867e-402e-ad3b-3daa316db155 (Archive number)f406d3dd-867e-402e-ad3b-3daa316db155 (OAI)
Note
Upprättat; 2013; 20130404 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-06-11Bibliographically approved
Gunasekera, K., Krishnaswamy, S., Loke, S. & Zaslavsky, A. (2012). Adaptation support for agent based pervasive systems (ed.). In: (Ed.), (Ed.), Mobile and Ubiquitous Systems: Computing, Networking, and Services: 7th International ICST Conference, MobiQuitous 2010, Sydeny, Australia, December 6-9, 2010, Revised Selected Papers. Paper presented at Annual International Conference on Mobile and Ubiquitous Systems : Computing, Networking, and Services 06/12/2010 - 09/12/2010 (pp. 90-101). Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag
Open this publication in new window or tab >>Adaptation support for agent based pervasive systems
2012 (English)In: Mobile and Ubiquitous Systems: Computing, Networking, and Services: 7th International ICST Conference, MobiQuitous 2010, Sydeny, Australia, December 6-9, 2010, Revised Selected Papers, Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2012, p. 90-101Conference paper, Published paper (Refereed)
Abstract [en]

Pervasive computing systems execute in dynamic highly variable environments and need software that are context-aware and can adapt at runtime. Mobile agents are viewed as an enabling technology for building software for such environments due to their flexibility, migratory nature and scalability. This paper presents a novel approach which aims to further enhance this advantage by building compositionally adaptive mobile software agents that are also context-driven, component-based and have the ability to exchange their components with peer agents. We present the formal underpinnings of our approach and a decision making model which assists agent adaptation. We also describe our current implementation and experimental results to evaluate the benefits of the proposed approach.

Place, publisher, year, edition, pages
Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2012
Series
Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, ISSN 1867-8211 ; 73
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-32656 (URN)10.1007/978-3-642-29154-8_8 (DOI)736bac64-3919-4ea5-bb31-517b30fce180 (Local ID)978-3-642-29153-1 (ISBN)978-3-642-29154-8 (ISBN)736bac64-3919-4ea5-bb31-517b30fce180 (Archive number)736bac64-3919-4ea5-bb31-517b30fce180 (OAI)
Conference
Annual International Conference on Mobile and Ubiquitous Systems : Computing, Networking, and Services 06/12/2010 - 09/12/2010
Note
Validerad; 2012; 20121227 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-06-11Bibliographically approved
Saguna, S., Zaslavsky, A. & Chakraborty, D. (2012). Building activity definitions to recognize complex activities using an online activity toolkit (ed.). In: (Ed.), (Ed.), IEEE 13th International Conference on Mobile Data Management, MDM 2012: . Paper presented at International Conference on Mobile Data Management : 23/07/2012 - 26/07/2012 (pp. 344-347). Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>Building activity definitions to recognize complex activities using an online activity toolkit
2012 (English)In: IEEE 13th International Conference on Mobile Data Management, MDM 2012, Piscataway, NJ: IEEE Communications Society, 2012, p. 344-347Conference paper, Published paper (Refereed)
Abstract [en]

One of the biggest challenges in the field of activity recognition is gathering training data for building activity inference models. To address this problem, we have developed an online activity toolkit for gathering activity data from online users. We use this data to build activity definitions for use in our system which is based on Context-Driven Activity Theory. We use Markov chain analysis to assign weights to activities and context attributes of a complex activity as well as to build activity signatures based on transition and path probabilities. Our demo is intended to show how complex activities and associated atomic activities and context attributes can be described using an activity toolkit. The toolkit is used to take input from users available online and the results analysis of different complex activities can be viewed online in near real-time using the graphical user interface (GUI).

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2012
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-34255 (URN)10.1109/MDM.2012.73 (DOI)866f52de-e2af-4995-b4c5-97390a8da692 (Local ID)9780769547138 (ISBN)866f52de-e2af-4995-b4c5-97390a8da692 (Archive number)866f52de-e2af-4995-b4c5-97390a8da692 (OAI)
Conference
International Conference on Mobile Data Management : 23/07/2012 - 26/07/2012
Note
Godkänd; 2012; 20121219 (andbra)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-06-28Bibliographically approved
Saguna, S., Zaslavsky, A. & Paris, C. (2012). Context-Aware Twitter Validator (CATVal): a system to validate credibility and authenticity of Twitter content for use in decision support systems (ed.). In: (Ed.), Ana Respício; Frada Burstein (Ed.), Fusing Decision Support Systems into the Fabric of the Context: . Paper presented at IFIP WG8.3 International Conference on Decision Support Systems : 28/06/2012 - 30/06/2012 (pp. 323-334). Anávissos, Greece: IOS Press
Open this publication in new window or tab >>Context-Aware Twitter Validator (CATVal): a system to validate credibility and authenticity of Twitter content for use in decision support systems
2012 (English)In: Fusing Decision Support Systems into the Fabric of the Context / [ed] Ana Respício; Frada Burstein, Anávissos, Greece: IOS Press, 2012, p. 323-334Conference paper, Published paper (Refereed)
Abstract [en]

Decision support systems (DSS) are beginning to use content sourced from social networks such as Twitter to provide decision makers with information to make timely and critical decisions. Misleading information obtained from Twitter can lead to adverse outcomes as well as cause trust issues within DSSs. In this paper, we propose and investigate a context-aware Twitter validator (CATVal) system to validate credibility and authenticity of Twitter content at run-time for use in DSS. We build, store and update a credibility index for Twitter users and verify user's context information each time a user tweets. The proposed system can benefit a DSS by providing credible and dependable information while detecting misleading and false information sourced from Twitter and possible other social media.

Place, publisher, year, edition, pages
Anávissos, Greece: IOS Press, 2012
Series
Frontiers in Artificial Intelligence and Applications, ISSN 0922-6389 ; 238
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-39568 (URN)10.3233/978-1-61499-073-4-323 (DOI)000349033900028 ()e616b9e0-5927-4dfe-a2ec-ceff15da29aa (Local ID)978-1-61499-072-7 (ISBN)978-1-61499-073-4 (ISBN)e616b9e0-5927-4dfe-a2ec-ceff15da29aa (Archive number)e616b9e0-5927-4dfe-a2ec-ceff15da29aa (OAI)
Conference
IFIP WG8.3 International Conference on Decision Support Systems : 28/06/2012 - 30/06/2012
Note
Validerad; 2013; 20130423 (saguna)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2018-07-10Bibliographically approved
Ranjan, R., Mitra, K., Saha, S., Georgakopoulos, D. & Zaslavsky, A. (2012). Do-it-yourself content delivery network orchestrator (ed.). In: (Ed.), (Ed.), Web Information Systems Engineering - WISE 2012: 13th International Conference, Paphos, Cyprus, November 28-30, 2012. Proceedings. Paper presented at International Conference on Web Information System Engineering : 27/11/2012 - 30/11/2012 (pp. 789-791). Piscataway, NJ: Encyclopedia of Global Archaeology/Springer Verlag
Open this publication in new window or tab >>Do-it-yourself content delivery network orchestrator
Show others...
2012 (English)In: Web Information Systems Engineering - WISE 2012: 13th International Conference, Paphos, Cyprus, November 28-30, 2012. Proceedings, Piscataway, NJ: Encyclopedia of Global Archaeology/Springer Verlag, 2012, p. 789-791Conference paper, Published paper (Refereed)
Abstract [en]

Content delivery networks (CDNs) [1] provide fast and reliable content access to the end-users. CDN providers (e.g., Akamai [2]), either own the entire infrastructure or it is outsourced to a single Cloud provider. Content owners (e.g., clients and end-users) need to establish expensive contracts with third party ISPs or CDN providers. Hence, existing CDN services are out of reach for all but large enterprises. Current CDNs do not provide services that allow an end-user to create dynamic content such as combining music videos from an existing content source on the Internet. Finally, the content owners do not have low-level control over the orchestration operations such as, multiple Cloud provider selection and resource management for hosting content. Hence, the content owners are dependent on their CDN providers to perform these operations behind the scene.

Place, publisher, year, edition, pages
Piscataway, NJ: Encyclopedia of Global Archaeology/Springer Verlag, 2012
Series
Lecture Notes in Computer Science, ISSN 0302-9743 ; 7615
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-40374 (URN)10.1007/978-3-642-35063-4_67 (DOI)f760b2ac-5771-45bd-9246-918ddbeb41be (Local ID)978-3-642-35062-7 (ISBN)978-3-642-35063-4 (ISBN)f760b2ac-5771-45bd-9246-918ddbeb41be (Archive number)f760b2ac-5771-45bd-9246-918ddbeb41be (OAI)
Conference
International Conference on Web Information System Engineering : 27/11/2012 - 30/11/2012
Note
Validerad; 2012; 20120913 (karan)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2018-06-11Bibliographically approved
Mitra, K., Zaslavsky, A. & Åhlund, C. (2012). Measuring quality of experience in pervasive systems using probabilistic context-aware approach (ed.). In: (Ed.), (Ed.), Mobile and Ubiquitous Systems: Computing, Networking, and Services: 7th International ICST Conference, MobiQuitous 2010, Sydney, Australia, December 6-9, 2010, Revised Selected Papers. Paper presented at Annual International Conference on Mobile and Ubiquitous Systems : Computing, Networking, and Services 06/12/2010 - 09/12/2010 (pp. 330-331). Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag
Open this publication in new window or tab >>Measuring quality of experience in pervasive systems using probabilistic context-aware approach
2012 (English)In: Mobile and Ubiquitous Systems: Computing, Networking, and Services: 7th International ICST Conference, MobiQuitous 2010, Sydney, Australia, December 6-9, 2010, Revised Selected Papers, Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2012, p. 330-331Conference paper, Published paper (Refereed)
Abstract [en]

In this paper, we pioneer a context-aware approach for quality of experience (QoE) modeling, reasoning and inferencing in mobile and pervasive computing environments. The proposed model is based upon Context Spaces Theory (CST) and influence diagrams (IDs) to handle uncertain and hidden complex inter-dependencies between user-perceived and network level QoS and to calculate overall QoE of the users. This helps in user-related media, network and device adaptation, creating user-level SLAs and minimizing network churn. We perform experimentation to validate the proposed approach and the results verify its modeling and inferencing capabilities.

Place, publisher, year, edition, pages
Heidelberg: Encyclopedia of Global Archaeology/Springer Verlag, 2012
Series
Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, ISSN 1867-8211 ; 73
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-35095 (URN)10.1007/978-3-642-29154-8_32 (DOI)97c12b3a-51c2-44ae-abc2-a6a2997f7f4e (Local ID)978-3-642-29153-1 (ISBN)978-3-642-29154-8 (ISBN)97c12b3a-51c2-44ae-abc2-a6a2997f7f4e (Archive number)97c12b3a-51c2-44ae-abc2-a6a2997f7f4e (OAI)
Conference
Annual International Conference on Mobile and Ubiquitous Systems : Computing, Networking, and Services 06/12/2010 - 09/12/2010
Note
Validerad; 2012; 20121227 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-06-11Bibliographically approved
Mitra, K., Åhlund, C. & Zaslavsky, A. (2012). Performance evaluation of a decision-theoretic approach for quality of experience measurement in mobile and pervasive computing scenarios (ed.). In: (Ed.), (Ed.), 2012 IEEE Wireless Communications and Networking Conference (WCNC): . Paper presented at IEEE Wireless Communications and Networking Conference : 01/04/2012 - 04/04/2012 (pp. 2418-2423). Piscataway, NJ: IEEE Communications Society
Open this publication in new window or tab >>Performance evaluation of a decision-theoretic approach for quality of experience measurement in mobile and pervasive computing scenarios
2012 (English)In: 2012 IEEE Wireless Communications and Networking Conference (WCNC), Piscataway, NJ: IEEE Communications Society, 2012, p. 2418-2423Conference paper, Published paper (Refereed)
Abstract [en]

Measuring and predicting users quality of experience (QoE) in dynamic network conditions is a challenging task. This paper presents results related to a decision-theoretic methodology incorporating Bayesian networks (BNs) and utility theory for quality of experience (QoE) measurement and prediction in mobile computing scenarios. In particular, we show how both generative and discriminative BNs can be used to measure and predict users QoE accurately for voice applications under several wireless network conditions such as wireless signal fading, vertical handoffs, wireless network congestion and normal hotspot traffic. Through extensive simulation studies and results analysis, we show that our proposed methodology can achieve an average accuracy of 98.70% using three different types of Bayesian network.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE Communications Society, 2012
Series
IEEE Wireless Communications and Networking Conference, ISSN 1525-3511
National Category
Media and Communication Technology
Research subject
Mobile and Pervasive Computing
Identifiers
urn:nbn:se:ltu:diva-31949 (URN)10.1109/WCNC.2012.6214201 (DOI)2-s2.0-84864359867 (Scopus ID)645b60f0-8594-4915-b9a4-b53d56693093 (Local ID)978-1-4673-0436-8 (ISBN)645b60f0-8594-4915-b9a4-b53d56693093 (Archive number)645b60f0-8594-4915-b9a4-b53d56693093 (OAI)
Conference
IEEE Wireless Communications and Networking Conference : 01/04/2012 - 04/04/2012
Note
Validerad; 2012; 20120629 (karan)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-07-10Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1990-5734

Search in DiVA

Show all publications