Francois Siewe | De Montfort University (original) (raw)
Papers by Francois Siewe
2020 IEEE 44th Annual Computers, Software, and Applications Conference (COMPSAC), 2020
This paper proposes an approach to analysing and verifying Petri nets using a Calculus of Context... more This paper proposes an approach to analysing and verifying Petri nets using a Calculus of Context-aware Ambients (CCA). We propose an algorithm that transforms a Petri net into a CCA process. This demonstrates that any system that can be specified in Petri nets can also be specified in CCA. Besides, the system can be analysed and verified using the CCA verification tools. We illustrate the practicality of our approach using a case study of the dining cryptographers problem.
In Pervasive computing environment, context-aware systems face many challenges to keep high quali... more In Pervasive computing environment, context-aware systems face many challenges to keep high quality performance. One-challenge faces context-aware systems is conflicted values come from different sensors because of different reasons. These conflicts affect the quality of context and as a result the quality of service as a whole. This paper is extension to our previous work, which is published in [15]. In our previous work, we presented an approach for resolving context conflicts in context-aware systems. This approach is could RCCAR (Resolving Context Conflicts Using Association Rules). RCCAR is implemented and verified well in [15], this paper conducts further experiments to explore the performance of RCCAR in comparison with the traditional prediction methods. The basic prediction methods that have been tested include simple moving average, weighted moving average, single exponential smoothing, double exponential smoothing, and ARMA. Experiments is conducted using Weka 3.7.7 and E...
Advances in Intelligent Systems and Computing, 2020
Proactive is one main aspect of ubiquitous context-aware systems in IoT environment. Ubiquitous c... more Proactive is one main aspect of ubiquitous context-aware systems in IoT environment. Ubiquitous context-aware systems in IoT environment needs a lightweight intelligent prediction techniques especially within fog and edge computing environment where technologies capabilities are poor. On the other hand, the data that ubiquitous context-aware systems depends on to learn is big. This paper suggests a lightweight prediction algorithm to help such system to work effectively. The proposed algorithm is improvement of RCCAR algorithm. RCCAR utilizes association rules for prediction. The contribution of this paper is minimize the number of association rules by giving a priority for associations that produced of high order itemsets before the lowest ones. The prediction is scored and formulated mathematically using confidence association rules measure. A real dataset is used in many different scenario experiments. The proposed algorithm achieves good with reasonable prediction score. For future work, extensive experiments with many datasets is recommended.
Grid computing systems are complex and dynamic environments requiring appropriate automated manag... more Grid computing systems are complex and dynamic environments requiring appropriate automated management mechanisms, which would enable stable and reliable operation of the whole grid ecosystem. Moreover, the recent novel concept of mobile grid computing – a combination of grid systems with mobile devices – also requires new ways of monitoring the emerging security aspects, associated with the everincreasing role of network connections in mobile grids. Existing grid monitoring systems, albeit suitable for traditional, localised grid systems, seem to be ignoring the security dimension and do not offer appropriate support for enforcing security policies within a distributed grid system enhanced with mobile devices. Accordingly, in this paper we present the Grid Security Policy Monitoring System (GridSPMS) – a novel grid monitoring framework, which extends the traditional support for data monitoring (i.e., tools, protocols, etc.) with mechanisms for collecting run-time data within grids,...
Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of w... more Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of wearable computing, mobile computing, robotics, adaptive and intelligent user interfaces. Sensors are the corner stone of context capturing however, sensed context data are commonly prone to imperfection due to the technical limitations of sensors, their availability, dysfunction, and highly dynamic nature of environment. Consequently, sensed context data might be imprecise, erroneous, conflicting, or simply missing. To limit the impact of context imperfection on the behavior of a context-aware system, a notion of Quality of Context (QoC) is used to measure quality of any information that is used as context information. Adaptation is performed only if the context data used in the decision-making has an appropriate quality level. This paper reports an analytical review the state of the art on quality of context in context-aware systems and points to future research directions.
A context-aware whiteboard system provides a number of services in a smart classroom including re... more A context-aware whiteboard system provides a number of services in a smart classroom including registering students as they enter the classroom; logging students and lecturers in to the blackboard virtual learning environment at the beginning of each lecture and logging them out at the end of the lecture. This system also notifies students of their absence to a lecture and maintains a list of attendance automatically. Using information from the timetable, it is aware of the lectures that are scheduled to take place in the classroom and the students that are allowed to attend these lectures. Finally, it allows students and lecturers to interact with teaching materials such as lecture slides and videos stored in the blackboard virtual learning environment. This paper proposes a formal specification of the white board system in the Calculus of Context-aware Ambients (CCA in short). This enables the formal analysis of the white board system using the execution environment of CCA. Some i...
Context-aware systems (CASs) have become a reality thanks to the development of smart software an... more Context-aware systems (CASs) have become a reality thanks to the development of smart software and hardware to assist the users in various real life activities. The proliferation of context-aware services has led to the emergence of environments where services are made available for usage anywhere and at any time. CASs have the ability to capture users’ contexts and use their instance values to provide self-adaptive services in response to context changes. Modelling and documenting the structure of such a system during the design phase is vital for system validation, testing, maintenance and version management. The Unified Modelling Language (UML) is the de facto industrial standard for system modelling and development. The UML class diagrams provide notations for modelling graphically the structure of a system in terms of classes and the relationships between them. However, these notations are insufficient to model the structure of CASs. This paper proposes a new set of notations t...
Applied System Innovation, 2021
The quality of execution tracing impacts the time to a great extent to locate errors in software ... more The quality of execution tracing impacts the time to a great extent to locate errors in software components; moreover, execution tracing is the most suitable tool, in the majority of the cases, for doing postmortem analysis of failures in the field. Nevertheless, software product quality models do not adequately consider execution tracing quality at present neither do they define the quality properties of this important entity in an acceptable manner. Defining these quality properties would be the first step towards creating a quality model for execution tracing. The current research fills this gap by identifying and defining the variables, i.e., the quality properties, on the basis of which the quality of execution tracing can be judged. The present study analyses the experiences of software professionals in focus groups at multinational companies, and also scrutinises the literature to elicit the mentioned quality properties. Moreover, the present study also contributes to knowled...
EAI Endorsed Transactions on Cloud Systems, 2020
The use of cloud computing (CC) is rapidly increasing due to the demand for internet services and... more The use of cloud computing (CC) is rapidly increasing due to the demand for internet services and communications. The large number of services and data stored in the cloud creates security risks due to the dynamic movement of data, connected devices and users between various cloud environments. In this study, we will develop an innovative prototype for location-aware access control and data privacy for CC systems. We will apply location-aware access control policies to role-based access control of Cloud Foundry, and then analyze the impact on user privacy after implementing these policies. This innovation can be used to address the security risks introduced by inter-cloud use and communication, and will have significant impact in making citizen's personal data more secure.
SN Computer Science, 2020
Software product quality models have evolved in their abilities to capture and describe the abstr... more Software product quality models have evolved in their abilities to capture and describe the abstract notion of software quality since the 1970's. Many models constructed deal with a specific part of software quality only which makes them ineligible to assess the quality of software products as a whole. Former publications failed to thoroughly examine and list all the available models which attempt to describe each known property of software product quality. This paper discovers such complete software product quality models published since 2000; moreover, it endeavours to measure the relevance of each model quantitatively by introducing indicators with regard to the scientific and industrial community. The identified 23 software product quality model classes differ significantly in terms of publication intensity, publication range, quality score average, relevance score and the 12-month average of the Google Relative Search Index. The results offer a foundation for selecting the appropriate software product quality model for use or for extension if newly identified quality properties need to be connected to a general context. Furthermore, the experiences accumulated on the field of software product quality modelling motivated researchers to successfully transfer the concepts to other areas where abstract entities
International Journal of Intelligent Computing Research, 2016
Use case diagrams are an excellent tool for capturing and analyzing the functional requirements o... more Use case diagrams are an excellent tool for capturing and analyzing the functional requirements of a system under development. Context-aware use case diagrams are an extension of use case diagrams to cater for both the functional requirements and the context-awareness requirements of context-aware and pervasive systems. They provide (graphical) notations for specifying, visualizing and documenting the intended behavior of a context-aware system at an early stage of the system development life-cycle. This paper proposes an approach to analyzing contextaware use case diagrams usind a Calculus of Context-aware Ambients (CCA). An algorithm is proposed that translates a context-aware use case diagram into a CCA process. This process can then be analyzed using the CCA tools such as the simulator ccaPL which enables the execution of CCA processes and the model-checker ccaSPIN that can check automatically whether a CCA process satisfies a desired property, e.g. deadlock freedom and reachability. The proposed approach is evaluated using a real-word example of a context-aware pedestrian collision avoidance system.
Transactions on Emerging Telecommunications Technologies, 2019
Smart Home Systems (SHSs) provide several services which are tailored to different residents' pre... more Smart Home Systems (SHSs) provide several services which are tailored to different residents' preferences. As a result, SHSs are highly exposed to undesirable interactions, known as feature interactions (FIs). FIs might occur as a result of a conflict in services' goals or a conflict with residents' preferences. Previous studies have proposed solutions based on applying priorities, in which some services or preferable features are disabled in favour of other services. Alternatively, the agent-based negotiation approach (ABNA) utilises agents and applies negotiation, enabling services with contrary features to work simultaneously. ABNA avoids applying priority between services or house residents' preferences whenever a space for a compromise exists. The mechanism of ABNA is based on the use of a hierarchy of features based on their contribution to the function of the service or on the importance of these features to house residents. To achieve a compromise between conflicting services, ABNA models services and residents by using agents, and implements a negotiation algorithm that allows services with conflicting features to work simultaneously. This paper presents a description of ABNA with a formal specification of ABNA in the Calculus of Context-aware Ambient (CCA). This enables the formal analysis of ABNA by using the execution environment of CCA.
IEEE Access, 2019
The e-learning recommender system in learning institutions is increasingly becoming the preferred... more The e-learning recommender system in learning institutions is increasingly becoming the preferred mode of delivery, as it enables learning anytime, anywhere. However, delivering personalised course learning objects based on student's preferences is still a challenge. Current mainstream recommendation algorithms, such as the Collaborative Filtering (CF) and Content-Based Filtering (CBF), deal with only two types of entities, namely users and items with their ratings. However, these methods do not pay attention to student's preferences, such as learning styles, which are especially important for the accuracy of course learning objects prediction or recommendation. Moreover, several recommendation techniques experience cold-start and rating sparsity problems. To address the challenge of improving the quality of recommender systems, in this paper a novel recommender algorithm for machine learning is proposed, which combines students actual rating with their learning styles to recommend personalised course learning objects (LOs). Various recommendation techniques are considered in an experimental study investigating the best technique to use in predicting student ratings for e-learning recommender systems. We use the Felder-Silverman Learning Styles Model (FSLSM) to represent both the student learning styles and the learning object profiles. The predicted ratings are compared with the actual student ratings to determine the accuracy of the recommendation techniques, using the Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) metrics. This approach has been experimented on 80 students for an online course created in the MOODLE Learning Management System. The results of the experiment show that the best recommendation technique is our proposed hybrid recommendation algorithm that combines the collaborative filtering and the contentbased filtering techniques to enhance the accuracy of the predictions, and solves the cold-start and the rating sparsity problems using the FSLSM representations of the student learning styles and the learning object profiles. INDEX TERMS Collaborative filtering (CF), content-based filtering (CBF), e-learning, Felder-Silverman learning style model (FSLSM), hybrid filtering (HF), rating prediction, recommendation system.
International Journal of Pervasive Computing and Communications, 2018
PurposeThis paper aims to introduce a comprehensive framework for quality of context in pervasive... more PurposeThis paper aims to introduce a comprehensive framework for quality of context in pervasive context-aware systems. The framework includes the context quality characteristics, the quality policy, the quality calculation methods and the quality control algorithm.Design/methodology/approachThis study used the constructive research method to introduce the framework. The data of a context-aware flooding prediction system to evaluate the approach were used.FindingsThe framework improves the quality of captured context by resolving the missing, error context and the context conflicts using the quality characteristics and quality control process that are introduced in the framework.Originality/valueThis work is original. It is based on the author’s PhD work in De Montfort University.
EAI Endorsed Transactions on Context-aware Systems and Applications, 2017
Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of w... more Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of wearable computing, mobile computing, robotics, adaptive and intelligent user interfaces. Sensors are the corner stone of context capturing however, sensed context data are commonly prone to imperfection due to the technical limitations of sensors, their availability, dysfunction, and highly dynamic nature of environment. Consequently, sensed context data might be imprecise, erroneous, conflicting, or simply missing. To limit the impact of context imperfection on the behavior of a context-aware system, a notion of Quality of Context (QoC) is used to measure quality of any information that is used as context information. Adaptation is performed only if the context data used in the decision-making has an appropriate quality level. This paper reports an analytical review for state of the art quality of context in context-aware systems and points to future research directions.
Journal of Parallel and Distributed Computing, 2016
h i g h l i g h t s • Propose CASAS, a paradigm for modelling secure pervasive computing systems.... more h i g h l i g h t s • Propose CASAS, a paradigm for modelling secure pervasive computing systems. • Present the syntax and a formal semantics for CASAS. • Present an algorithm for checking system consistency statically (i.e. at compile time). • Define a set of operators for building complex CASAS systems from simpler ones in a compositional manner. • Demonstrate the pragmatics of the proposed formalism using a number of real-world case studies.
EAI Endorsed Transactions on e-Learning, 2016
Nowadays, most of the existing e-learning architecture provides the same content to all learners ... more Nowadays, most of the existing e-learning architecture provides the same content to all learners due to "one size fits for all" concept. E-learning refers to the utilization of electronic innovations to convey and encourage training anytime and anywhere. There is a need to create a personalized environment that involves collecting a range of information about each learner. Questionnaires are one way of gathering information on learning style, but there are some problems with their usage, such as reluctance to answer questions as well as guesses the answer being time consuming. Ontology-based semantic retrieval is a hotspot of current research, because ontologies play a paramount part in the development of knowledge. In this paper, a novel way to build an adaptive student profile by analysis of learning patterns through a learning management system, according to the Felder-Silverman learning style model (FSLSM) and Myers-Briggs Type Indicator (MBTI) theory is proposed.
2015 10th International Conference for Internet Technology and Secured Transactions (ICITST), 2015
This paper proposes an approach to translating a use case diagram into an executable context-awar... more This paper proposes an approach to translating a use case diagram into an executable context-aware ambients. The requirements of a context-aware system is captured and represented in an extension of UML use case diagrams called context-aware use case diagrams. Then an algorithm is proposed that translates a context-aware use case diagram into a process in the Calculus of Context-aware Ambients (CCA). This process can then be analyzed using the CCA simulator. The proposed approach is evaluated using a real-word example of a contextaware collision avoidance system.
Journal of Systems and Software, 2016
Ubiquitous computing systems collect and share a great deal of information upon the users and the... more Ubiquitous computing systems collect and share a great deal of information upon the users and their environment; including private or highly sensitive personal information. Unless users are confident enough that their privacy is protected, many will be deterred from using such systems. This paper proposes a privacy type system that controls the behaviour of concurrent, context-aware and mobile processes to ensure that private information is not accidentally disclosed. We prove the subject reduction property and the soundness of the proposed type system; which guarantee that a well-typed process cannot accidentally disclose private information. We demonstrate the pragmatics of our approach with a case study.
2016 SAI Computing Conference (SAI), 2016
Grid computing systems are complex and dynamic systems and therefore require appropriate automate... more Grid computing systems are complex and dynamic systems and therefore require appropriate automated management, which would enable stable and reliable operation of the whole grid environment. The research community has addressed this requirement with a number of monitoring frameworks, which serve to collect data at various levels to support decision taking and management activities within grids. However, these existing solutions seem to implement little support for collecting security-related data and enforcing appropriate security policies and constraints in this respect. With an increasing role of network connections and users remotely accessing computational resources from various locations, grid systems are no longer seen as localised and isolated ecosystems, but are coming to be more open and distributed. In this light, it is becoming more and more important to enable monitoring framework with capabilities to collect security-related data and check whether these observations comply with certain security constraints. Accordingly, this paper presents a survey of existing grid monitoring systems with a goal to identify an existing gap of insufficient support for handling the security dimension in grids. The survey suggests that available grid monitoring frameworks are incapable of collecting security-related data metrics and evaluating them against a set of security policies. As a first step towards addressing this issue, the paper outlines several groups of security policies, which the authors expect to be further incorporated in their own research work, and by the wider community.
2020 IEEE 44th Annual Computers, Software, and Applications Conference (COMPSAC), 2020
This paper proposes an approach to analysing and verifying Petri nets using a Calculus of Context... more This paper proposes an approach to analysing and verifying Petri nets using a Calculus of Context-aware Ambients (CCA). We propose an algorithm that transforms a Petri net into a CCA process. This demonstrates that any system that can be specified in Petri nets can also be specified in CCA. Besides, the system can be analysed and verified using the CCA verification tools. We illustrate the practicality of our approach using a case study of the dining cryptographers problem.
In Pervasive computing environment, context-aware systems face many challenges to keep high quali... more In Pervasive computing environment, context-aware systems face many challenges to keep high quality performance. One-challenge faces context-aware systems is conflicted values come from different sensors because of different reasons. These conflicts affect the quality of context and as a result the quality of service as a whole. This paper is extension to our previous work, which is published in [15]. In our previous work, we presented an approach for resolving context conflicts in context-aware systems. This approach is could RCCAR (Resolving Context Conflicts Using Association Rules). RCCAR is implemented and verified well in [15], this paper conducts further experiments to explore the performance of RCCAR in comparison with the traditional prediction methods. The basic prediction methods that have been tested include simple moving average, weighted moving average, single exponential smoothing, double exponential smoothing, and ARMA. Experiments is conducted using Weka 3.7.7 and E...
Advances in Intelligent Systems and Computing, 2020
Proactive is one main aspect of ubiquitous context-aware systems in IoT environment. Ubiquitous c... more Proactive is one main aspect of ubiquitous context-aware systems in IoT environment. Ubiquitous context-aware systems in IoT environment needs a lightweight intelligent prediction techniques especially within fog and edge computing environment where technologies capabilities are poor. On the other hand, the data that ubiquitous context-aware systems depends on to learn is big. This paper suggests a lightweight prediction algorithm to help such system to work effectively. The proposed algorithm is improvement of RCCAR algorithm. RCCAR utilizes association rules for prediction. The contribution of this paper is minimize the number of association rules by giving a priority for associations that produced of high order itemsets before the lowest ones. The prediction is scored and formulated mathematically using confidence association rules measure. A real dataset is used in many different scenario experiments. The proposed algorithm achieves good with reasonable prediction score. For future work, extensive experiments with many datasets is recommended.
Grid computing systems are complex and dynamic environments requiring appropriate automated manag... more Grid computing systems are complex and dynamic environments requiring appropriate automated management mechanisms, which would enable stable and reliable operation of the whole grid ecosystem. Moreover, the recent novel concept of mobile grid computing – a combination of grid systems with mobile devices – also requires new ways of monitoring the emerging security aspects, associated with the everincreasing role of network connections in mobile grids. Existing grid monitoring systems, albeit suitable for traditional, localised grid systems, seem to be ignoring the security dimension and do not offer appropriate support for enforcing security policies within a distributed grid system enhanced with mobile devices. Accordingly, in this paper we present the Grid Security Policy Monitoring System (GridSPMS) – a novel grid monitoring framework, which extends the traditional support for data monitoring (i.e., tools, protocols, etc.) with mechanisms for collecting run-time data within grids,...
Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of w... more Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of wearable computing, mobile computing, robotics, adaptive and intelligent user interfaces. Sensors are the corner stone of context capturing however, sensed context data are commonly prone to imperfection due to the technical limitations of sensors, their availability, dysfunction, and highly dynamic nature of environment. Consequently, sensed context data might be imprecise, erroneous, conflicting, or simply missing. To limit the impact of context imperfection on the behavior of a context-aware system, a notion of Quality of Context (QoC) is used to measure quality of any information that is used as context information. Adaptation is performed only if the context data used in the decision-making has an appropriate quality level. This paper reports an analytical review the state of the art on quality of context in context-aware systems and points to future research directions.
A context-aware whiteboard system provides a number of services in a smart classroom including re... more A context-aware whiteboard system provides a number of services in a smart classroom including registering students as they enter the classroom; logging students and lecturers in to the blackboard virtual learning environment at the beginning of each lecture and logging them out at the end of the lecture. This system also notifies students of their absence to a lecture and maintains a list of attendance automatically. Using information from the timetable, it is aware of the lectures that are scheduled to take place in the classroom and the students that are allowed to attend these lectures. Finally, it allows students and lecturers to interact with teaching materials such as lecture slides and videos stored in the blackboard virtual learning environment. This paper proposes a formal specification of the white board system in the Calculus of Context-aware Ambients (CCA in short). This enables the formal analysis of the white board system using the execution environment of CCA. Some i...
Context-aware systems (CASs) have become a reality thanks to the development of smart software an... more Context-aware systems (CASs) have become a reality thanks to the development of smart software and hardware to assist the users in various real life activities. The proliferation of context-aware services has led to the emergence of environments where services are made available for usage anywhere and at any time. CASs have the ability to capture users’ contexts and use their instance values to provide self-adaptive services in response to context changes. Modelling and documenting the structure of such a system during the design phase is vital for system validation, testing, maintenance and version management. The Unified Modelling Language (UML) is the de facto industrial standard for system modelling and development. The UML class diagrams provide notations for modelling graphically the structure of a system in terms of classes and the relationships between them. However, these notations are insufficient to model the structure of CASs. This paper proposes a new set of notations t...
Applied System Innovation, 2021
The quality of execution tracing impacts the time to a great extent to locate errors in software ... more The quality of execution tracing impacts the time to a great extent to locate errors in software components; moreover, execution tracing is the most suitable tool, in the majority of the cases, for doing postmortem analysis of failures in the field. Nevertheless, software product quality models do not adequately consider execution tracing quality at present neither do they define the quality properties of this important entity in an acceptable manner. Defining these quality properties would be the first step towards creating a quality model for execution tracing. The current research fills this gap by identifying and defining the variables, i.e., the quality properties, on the basis of which the quality of execution tracing can be judged. The present study analyses the experiences of software professionals in focus groups at multinational companies, and also scrutinises the literature to elicit the mentioned quality properties. Moreover, the present study also contributes to knowled...
EAI Endorsed Transactions on Cloud Systems, 2020
The use of cloud computing (CC) is rapidly increasing due to the demand for internet services and... more The use of cloud computing (CC) is rapidly increasing due to the demand for internet services and communications. The large number of services and data stored in the cloud creates security risks due to the dynamic movement of data, connected devices and users between various cloud environments. In this study, we will develop an innovative prototype for location-aware access control and data privacy for CC systems. We will apply location-aware access control policies to role-based access control of Cloud Foundry, and then analyze the impact on user privacy after implementing these policies. This innovation can be used to address the security risks introduced by inter-cloud use and communication, and will have significant impact in making citizen's personal data more secure.
SN Computer Science, 2020
Software product quality models have evolved in their abilities to capture and describe the abstr... more Software product quality models have evolved in their abilities to capture and describe the abstract notion of software quality since the 1970's. Many models constructed deal with a specific part of software quality only which makes them ineligible to assess the quality of software products as a whole. Former publications failed to thoroughly examine and list all the available models which attempt to describe each known property of software product quality. This paper discovers such complete software product quality models published since 2000; moreover, it endeavours to measure the relevance of each model quantitatively by introducing indicators with regard to the scientific and industrial community. The identified 23 software product quality model classes differ significantly in terms of publication intensity, publication range, quality score average, relevance score and the 12-month average of the Google Relative Search Index. The results offer a foundation for selecting the appropriate software product quality model for use or for extension if newly identified quality properties need to be connected to a general context. Furthermore, the experiences accumulated on the field of software product quality modelling motivated researchers to successfully transfer the concepts to other areas where abstract entities
International Journal of Intelligent Computing Research, 2016
Use case diagrams are an excellent tool for capturing and analyzing the functional requirements o... more Use case diagrams are an excellent tool for capturing and analyzing the functional requirements of a system under development. Context-aware use case diagrams are an extension of use case diagrams to cater for both the functional requirements and the context-awareness requirements of context-aware and pervasive systems. They provide (graphical) notations for specifying, visualizing and documenting the intended behavior of a context-aware system at an early stage of the system development life-cycle. This paper proposes an approach to analyzing contextaware use case diagrams usind a Calculus of Context-aware Ambients (CCA). An algorithm is proposed that translates a context-aware use case diagram into a CCA process. This process can then be analyzed using the CCA tools such as the simulator ccaPL which enables the execution of CCA processes and the model-checker ccaSPIN that can check automatically whether a CCA process satisfies a desired property, e.g. deadlock freedom and reachability. The proposed approach is evaluated using a real-word example of a context-aware pedestrian collision avoidance system.
Transactions on Emerging Telecommunications Technologies, 2019
Smart Home Systems (SHSs) provide several services which are tailored to different residents' pre... more Smart Home Systems (SHSs) provide several services which are tailored to different residents' preferences. As a result, SHSs are highly exposed to undesirable interactions, known as feature interactions (FIs). FIs might occur as a result of a conflict in services' goals or a conflict with residents' preferences. Previous studies have proposed solutions based on applying priorities, in which some services or preferable features are disabled in favour of other services. Alternatively, the agent-based negotiation approach (ABNA) utilises agents and applies negotiation, enabling services with contrary features to work simultaneously. ABNA avoids applying priority between services or house residents' preferences whenever a space for a compromise exists. The mechanism of ABNA is based on the use of a hierarchy of features based on their contribution to the function of the service or on the importance of these features to house residents. To achieve a compromise between conflicting services, ABNA models services and residents by using agents, and implements a negotiation algorithm that allows services with conflicting features to work simultaneously. This paper presents a description of ABNA with a formal specification of ABNA in the Calculus of Context-aware Ambient (CCA). This enables the formal analysis of ABNA by using the execution environment of CCA.
IEEE Access, 2019
The e-learning recommender system in learning institutions is increasingly becoming the preferred... more The e-learning recommender system in learning institutions is increasingly becoming the preferred mode of delivery, as it enables learning anytime, anywhere. However, delivering personalised course learning objects based on student's preferences is still a challenge. Current mainstream recommendation algorithms, such as the Collaborative Filtering (CF) and Content-Based Filtering (CBF), deal with only two types of entities, namely users and items with their ratings. However, these methods do not pay attention to student's preferences, such as learning styles, which are especially important for the accuracy of course learning objects prediction or recommendation. Moreover, several recommendation techniques experience cold-start and rating sparsity problems. To address the challenge of improving the quality of recommender systems, in this paper a novel recommender algorithm for machine learning is proposed, which combines students actual rating with their learning styles to recommend personalised course learning objects (LOs). Various recommendation techniques are considered in an experimental study investigating the best technique to use in predicting student ratings for e-learning recommender systems. We use the Felder-Silverman Learning Styles Model (FSLSM) to represent both the student learning styles and the learning object profiles. The predicted ratings are compared with the actual student ratings to determine the accuracy of the recommendation techniques, using the Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) metrics. This approach has been experimented on 80 students for an online course created in the MOODLE Learning Management System. The results of the experiment show that the best recommendation technique is our proposed hybrid recommendation algorithm that combines the collaborative filtering and the contentbased filtering techniques to enhance the accuracy of the predictions, and solves the cold-start and the rating sparsity problems using the FSLSM representations of the student learning styles and the learning object profiles. INDEX TERMS Collaborative filtering (CF), content-based filtering (CBF), e-learning, Felder-Silverman learning style model (FSLSM), hybrid filtering (HF), rating prediction, recommendation system.
International Journal of Pervasive Computing and Communications, 2018
PurposeThis paper aims to introduce a comprehensive framework for quality of context in pervasive... more PurposeThis paper aims to introduce a comprehensive framework for quality of context in pervasive context-aware systems. The framework includes the context quality characteristics, the quality policy, the quality calculation methods and the quality control algorithm.Design/methodology/approachThis study used the constructive research method to introduce the framework. The data of a context-aware flooding prediction system to evaluate the approach were used.FindingsThe framework improves the quality of captured context by resolving the missing, error context and the context conflicts using the quality characteristics and quality control process that are introduced in the framework.Originality/valueThis work is original. It is based on the author’s PhD work in De Montfort University.
EAI Endorsed Transactions on Context-aware Systems and Applications, 2017
Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of w... more Context-aware Systems (CASs) are becoming increasingly popular and can be found in the areas of wearable computing, mobile computing, robotics, adaptive and intelligent user interfaces. Sensors are the corner stone of context capturing however, sensed context data are commonly prone to imperfection due to the technical limitations of sensors, their availability, dysfunction, and highly dynamic nature of environment. Consequently, sensed context data might be imprecise, erroneous, conflicting, or simply missing. To limit the impact of context imperfection on the behavior of a context-aware system, a notion of Quality of Context (QoC) is used to measure quality of any information that is used as context information. Adaptation is performed only if the context data used in the decision-making has an appropriate quality level. This paper reports an analytical review for state of the art quality of context in context-aware systems and points to future research directions.
Journal of Parallel and Distributed Computing, 2016
h i g h l i g h t s • Propose CASAS, a paradigm for modelling secure pervasive computing systems.... more h i g h l i g h t s • Propose CASAS, a paradigm for modelling secure pervasive computing systems. • Present the syntax and a formal semantics for CASAS. • Present an algorithm for checking system consistency statically (i.e. at compile time). • Define a set of operators for building complex CASAS systems from simpler ones in a compositional manner. • Demonstrate the pragmatics of the proposed formalism using a number of real-world case studies.
EAI Endorsed Transactions on e-Learning, 2016
Nowadays, most of the existing e-learning architecture provides the same content to all learners ... more Nowadays, most of the existing e-learning architecture provides the same content to all learners due to "one size fits for all" concept. E-learning refers to the utilization of electronic innovations to convey and encourage training anytime and anywhere. There is a need to create a personalized environment that involves collecting a range of information about each learner. Questionnaires are one way of gathering information on learning style, but there are some problems with their usage, such as reluctance to answer questions as well as guesses the answer being time consuming. Ontology-based semantic retrieval is a hotspot of current research, because ontologies play a paramount part in the development of knowledge. In this paper, a novel way to build an adaptive student profile by analysis of learning patterns through a learning management system, according to the Felder-Silverman learning style model (FSLSM) and Myers-Briggs Type Indicator (MBTI) theory is proposed.
2015 10th International Conference for Internet Technology and Secured Transactions (ICITST), 2015
This paper proposes an approach to translating a use case diagram into an executable context-awar... more This paper proposes an approach to translating a use case diagram into an executable context-aware ambients. The requirements of a context-aware system is captured and represented in an extension of UML use case diagrams called context-aware use case diagrams. Then an algorithm is proposed that translates a context-aware use case diagram into a process in the Calculus of Context-aware Ambients (CCA). This process can then be analyzed using the CCA simulator. The proposed approach is evaluated using a real-word example of a contextaware collision avoidance system.
Journal of Systems and Software, 2016
Ubiquitous computing systems collect and share a great deal of information upon the users and the... more Ubiquitous computing systems collect and share a great deal of information upon the users and their environment; including private or highly sensitive personal information. Unless users are confident enough that their privacy is protected, many will be deterred from using such systems. This paper proposes a privacy type system that controls the behaviour of concurrent, context-aware and mobile processes to ensure that private information is not accidentally disclosed. We prove the subject reduction property and the soundness of the proposed type system; which guarantee that a well-typed process cannot accidentally disclose private information. We demonstrate the pragmatics of our approach with a case study.
2016 SAI Computing Conference (SAI), 2016
Grid computing systems are complex and dynamic systems and therefore require appropriate automate... more Grid computing systems are complex and dynamic systems and therefore require appropriate automated management, which would enable stable and reliable operation of the whole grid environment. The research community has addressed this requirement with a number of monitoring frameworks, which serve to collect data at various levels to support decision taking and management activities within grids. However, these existing solutions seem to implement little support for collecting security-related data and enforcing appropriate security policies and constraints in this respect. With an increasing role of network connections and users remotely accessing computational resources from various locations, grid systems are no longer seen as localised and isolated ecosystems, but are coming to be more open and distributed. In this light, it is becoming more and more important to enable monitoring framework with capabilities to collect security-related data and check whether these observations comply with certain security constraints. Accordingly, this paper presents a survey of existing grid monitoring systems with a goal to identify an existing gap of insufficient support for handling the security dimension in grids. The survey suggests that available grid monitoring frameworks are incapable of collecting security-related data metrics and evaluating them against a set of security policies. As a first step towards addressing this issue, the paper outlines several groups of security policies, which the authors expect to be further incorporated in their own research work, and by the wider community.