Kamel Barkaoui - Profile on Academia.edu (original) (raw)
Papers by Kamel Barkaoui
Innovations in Systems and Software Engineering, Dec 25, 2023
This special issue contains extended versions of selected papers from the 14th and 15th editions ... more This special issue contains extended versions of selected papers from the 14th and 15th editions of the International Conference on Verification and Evaluation of Computer and Communication Systems (VECoS 2020/21). VECoS 2021 was scheduled to take place in November 2021 at the Institute of Software, Chinese Academy of Sciences in Beijing (co-located with FM 2021), and VECoS 2020 in October 2020 in Xi'an University of Science and Technology (XUST). However, due to the COVID-19 epidemic, these two editions held as virtual conferences. The aim of the VECoS conference is to bring together researchers and practitioners in the areas of verification, control, performance, and dependability evaluation in order to discuss the state of the art and challenges in modern computer and communication systems in which functional and extra-functional properties are strongly interrelated. Thus, the main motivation for VECoS is to encourage cross-fertilization between various formal verification and evaluation approaches, methods, and techniques, and especially those developed for concurrent and distributed hardware/software systems. This issue comprises four papers (selected from the 26 accepted and presented papers) covering various aspects of computer and communication systems: specification, testing, verification, and evaluation. Using Quantitative Risk Assessment" by Mediouni et al. [1] This paper proposes a formal model-based approach for designing resilient systems incrementally by iterative and sound model transformations. A quantitative risk assessment and validation of system robustness is given by using B Kamel Barkaoui
Research Square (Research Square), Dec 24, 2023
We address in this paper how complex and dynamic environments characterized by variable limited c... more We address in this paper how complex and dynamic environments characterized by variable limited capacities and subject to transient unavailability may pose significant challenges for Deep Reinforcement Learning (DRL) agent. The investigation concerns the context of Service Function Chaining (SFC) orchestration problem in Software-Defined Networking (SDN) and Network Function Virtualization (NFV) based environments using DRL approach, implemented through Deep Q-Network (DQN), and aiming to maximize Quality of Experience (QoE) while meeting Quality of Service (QoS) constraints. We show through numerical results how limited capacity in Physical Substrate Network (PSN) complicates the training process in terms of finding suitable compromise between performance and convergence. We highlight also how replay buffer may mitigate transient unavailability of PSN nodes and what are the limits of such a solution when the unavailability becomes more prolonged in time or more severe (simultaneous unavailability of more than one node).
A QoE Driven DRL Approach for Network Slicing Based on SFC Orchestration in SDN/NFV Enabled Networks
Lecture Notes in Computer Science, Dec 18, 2023
arXiv (Cornell University), Oct 8, 2016
We propose in this paper a simulation implementation of Self-Organizing Networks (SON) optimizati... more We propose in this paper a simulation implementation of Self-Organizing Networks (SON) optimization related to mobility load balancing (MLB) for LTE systems using ns-3 . The implementation is achieved toward two MLB algorithms dynamically adjusting handover (HO) parameters based on the Reference Signal Received Power (RSRP) measurements. Such adjustments are done with respect to loads of both an overloaded cell and its cells' neighbours having enough available resources enabling to achieve load balancing. Numerical investigations through selected key performance indicators (KPIs) of the proposed MLB algorithms when compared with another HO algorithm (already implemented in ns-3) based on A3 event highlight the significant MLB gains provided in terms global network throughput, packet loss rate and the number of successful HO without incurring significant overhead.
Efficient Answer Extraction of Deductive Databases Modelled by HLPN
ABSTRACT
On concurrency Control in Mutlidatabase Systems with an Extented Transaction Model
HAL (Le Centre pour la Communication Scientifique Directe), 2003
HapiFabric: A Teleconsultation Framework Based on Hyperledger Fabric
Lecture notes in business information processing, 2020
Performance Study of IEEE 802.11 WLAN Integrating QoS requirements
ABSTRACT
BPM 2011 International Workshops, Clermont-Ferrand,France, August 29, 2011, Revised Selected Papers, Part II
HAL (Le Centre pour la Communication Scientifique Directe), Feb 12, 2012
ABSTRACT
Modelling and analyzing home care plans using high-level Petri nets
Given the constant pressure to improve healthcare efficiency, home care appears as a unique solut... more Given the constant pressure to improve healthcare efficiency, home care appears as a unique solution for providing personalized healthcare service and home assistance for a growing number of elderly and chronic patients. Home care plans define the health cares or supportive cares delivered by the different home care professionals for a given patient. The management of these plans is challenging since they are inherently flexible, context dependent and cooperative processes involving repetitive activities with complex temporal expressions. In this paper, we propose a formal method based time recursive ECATNets for modelling and analyzing home care plans. The choice of this formalism relies on its ability in modelling flexible and distributed home care processes, with complex temporal constraints. Moreover, since time recursive ECATNets semantics are expressed in terms of conditional rewriting logic, we can use the Real Time MAUDE TCTL model checker to verify temporal properties of home care plan processes.
Lecture notes in business information processing, 2012
The use of general descriptive names, registered names, trademarks, etc. in this publication does... more The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.
HapiChain: A Blockchain-based Framework for Patient-Centric Telemedicine
Given the exploding number of the elderly and patients with chronic diseases and the uneven distr... more Given the exploding number of the elderly and patients with chronic diseases and the uneven distribution of clinicians, it is economically impossible to continue traditional medicine. Hence, the healthcare sector has been gradually gravitating towards telemedicine, which applies intelligent systems for more comprehensive medical services with minimum costs. The criticality of data and process involved in telemedicine raise various concerns in terms of reliability and security. To this end, in this paper, we propose HapiChain, a blockchain-based framework for patient-centric telemedicine. HapiChain exploits blockchain technology to improve security, scalability, and reliability of medical workflows. Although HapiChain is patient-centric, it also helps the clinicians to save time and prevent unnecessary trips without improvising the level of treatment. In HapiChain, we embed two primary telemedicine services, namely telemonitoring and teleconsultation. For the former service, Hapicare, an existing healthcare monitoring system with self-adaptive coaching using probabilistic reasoning, is used. HapiChain then completes this service by adding teleconsultation services exploiting blockchain technology. The HapiChain framework includes three main layers: (i) interface layer, (ii) DApp layer, and (iii) blockchain layer. In the first layer, Hapicare is used to communicates with the users, i.e., patients and doctors. DApp layer includes the required procedures for security and scalability of HapiChain, namely smart contracts and distributed storage. The latter is achieved using the InterPlanetary File System (IPFS). In the blockchain layer, Ethereum blockchain is used as a platform of DApps. We evaluate the HapiChain framework and the proposed teleconsultation services in a use-case.
IEEE Access, 2019
Resources in a real-world automated manufacturing system may be unreliable, thus paralyzing many ... more Resources in a real-world automated manufacturing system may be unreliable, thus paralyzing many existing deadlock control strategies. This paper defines robust legal markings and proposes a twostep robust deadlock control policy for systems of the simple sequential process with resources based on elementary siphons. The first step, called elementary siphons control, derives a live controlled system without considering resource failures. The second step deals with failure-induced deadlocks control issues. With resource failures taken into account, recovery subnets modeling resource failures and recoveries are added to the first-step-derived system, which may cause the occurrence of failure-induced deadlocks, resulting in an unreliable controlled system. In order to make the system reliable, the definition that a resource failure is observed by a monitor is developed. A scenario is exposed that a resource failure does not need to be observed while can be observed by the added monitors. Arcs connecting recovery places and transitions of the initial system are added based on the obtained scenario. The concept of the extend the adjoint set of a siphon is presented due to a resource failure that needs to be observed while cannot be observed by the added monitors, leading to the modification of the arcs added in the first step. Consequently, a robust controlled system is acquired. Finally, examples are presented to demonstrate the proposed method. INDEX TERMS Automated manufacturing system, Petri net, deadlock prevention, robust control.
IFAC-PapersOnLine, 2018
This paper proposes a performability analysis based on stochastic reward nets (SRNs) of an energy... more This paper proposes a performability analysis based on stochastic reward nets (SRNs) of an energy-efficient server virtualized system (SVS) model handling data-intensive applications and implementing a workload-aware power management (PM) mechanism. The SVS model accounts for workload-aware dependent software aging, unplanned failures and Migrate-VM rejuvenation. We show through numerical analysis of perfomability metrics how workload burstiness and software aging impact SVS behavior in terms of availability and performance.
Advances in Mechanical Engineering, Dec 1, 2018
Business Process Model and Notation is known as a widely used standard for business processes mod... more Business Process Model and Notation is known as a widely used standard for business processes modeling. However, its main drawback is that it lacks formal semantics, leading to some undesirable properties, such as livelocks and deadlocks, such that it creates models with semantic errors. In order to formally verify them, we need to transform it onto a formal language, for example, Petri nets. The approach proposed in this article is an extension of previous approaches stated in the literature by adding probability to gateways and time to transitions. The first aim is to transform the Business Process Model and Notation process diagram onto Petri nets automatically using a developed software package. The developed software package is capable of transforming the XML file of a Business Process Model and Notation process diagram into ''m'' files of a Petri net. The ''m'' files of the Petri net are then coupled with the General Purpose Petri Net Simulator (GPenSIM) for analysis in MATLAB. The second aim is to manually transform the Business Process Model and Notation process diagram using mapping figures onto Petri nets and then analyze it using Timed Petri Net Analyzer tools. The advantage of transforming a Business Process Model and Notation diagram automatically is that we can add time to transitions and probability to gateways. Furthermore, the simulation time can be checked using MATLAB.
Modélisation des workflows collaboratifs à l'aide des ECATNets récursifs
HAL (Le Centre pour la Communication Scientifique Directe), 2008
Design and implementation of a massively parallel ESB
Enterprise Service Bus (ESB) is an SOA-based software architecture for business application integ... more Enterprise Service Bus (ESB) is an SOA-based software architecture for business application integration in distributed and heterogeneous environments. The proposed solutions so commercial as open source offer the same set of basic services such as message transformation, message routing, security. However, none of them take advantage of the multicore/multiprocessor technologies which make plausible the massively parallel processing. In this paper, we describe a new ESB architecture denoted Massively Parallel Application Bus (MPAB) which meets this challenge.
A Secure Data-Sharing Framework Based on Blockchain: Teleconsultation Use-Case
Springer eBooks, Dec 30, 2022
E-health telecommunication systems and networks, 2016
This Staphylococcus epidermidis has been discovered as the most frequent germ detected during ind... more This Staphylococcus epidermidis has been discovered as the most frequent germ detected during indwelling medical devices infection. This fact is well attached with the ability of this bacterium to form structured layered population known as biofilm. Inside S. epidermidis biofilm, bacterial cells present more different behavior than in their planktonic counterpart. This paper describes the thriving application of Petri net theory for modeling of interaction between different regulations actors leading S. epidermidis to switch from Planctonik to Biofilm. Indeed this biologic system is very sensible and has dangerous effect. We propose Agent Petri Nets model to describe and analyze the process of formation of Biofilm molecule. This model presents a formal framework based on Multi Agents system characteristics.
Innovations in Systems and Software Engineering, Feb 4, 2020
This paper deals with the partial order techniques of Petri nets, based on persistent sets and st... more This paper deals with the partial order techniques of Petri nets, based on persistent sets and step graphs methods. To take advantage of the strengths of each method, it proposes the persistent step sets as a parametric combination of the both methods. The persistent step sets method allows to fix, for each marking, the set of transitions S to be covered by the selected steps and then to control their maximal length and number. Depending on the parameter S, it computes covering-steps, persistent sets, persistent-step sets or other kinds of combination of both methods. Moreover, this persistent step selective search preserves, at least, deadlocks of Petri nets. Furthermore, this paper provides two practical computation procedures of the persistent step sets based on the strong-persistent sets and the weak-persistent sets, respectively. Finally, to achieve further reductions, it shows how to weaken the sufficient conditions used in the literature to build persistent sets.
Innovations in Systems and Software Engineering, Dec 25, 2023
This special issue contains extended versions of selected papers from the 14th and 15th editions ... more This special issue contains extended versions of selected papers from the 14th and 15th editions of the International Conference on Verification and Evaluation of Computer and Communication Systems (VECoS 2020/21). VECoS 2021 was scheduled to take place in November 2021 at the Institute of Software, Chinese Academy of Sciences in Beijing (co-located with FM 2021), and VECoS 2020 in October 2020 in Xi'an University of Science and Technology (XUST). However, due to the COVID-19 epidemic, these two editions held as virtual conferences. The aim of the VECoS conference is to bring together researchers and practitioners in the areas of verification, control, performance, and dependability evaluation in order to discuss the state of the art and challenges in modern computer and communication systems in which functional and extra-functional properties are strongly interrelated. Thus, the main motivation for VECoS is to encourage cross-fertilization between various formal verification and evaluation approaches, methods, and techniques, and especially those developed for concurrent and distributed hardware/software systems. This issue comprises four papers (selected from the 26 accepted and presented papers) covering various aspects of computer and communication systems: specification, testing, verification, and evaluation. Using Quantitative Risk Assessment" by Mediouni et al. [1] This paper proposes a formal model-based approach for designing resilient systems incrementally by iterative and sound model transformations. A quantitative risk assessment and validation of system robustness is given by using B Kamel Barkaoui
Research Square (Research Square), Dec 24, 2023
We address in this paper how complex and dynamic environments characterized by variable limited c... more We address in this paper how complex and dynamic environments characterized by variable limited capacities and subject to transient unavailability may pose significant challenges for Deep Reinforcement Learning (DRL) agent. The investigation concerns the context of Service Function Chaining (SFC) orchestration problem in Software-Defined Networking (SDN) and Network Function Virtualization (NFV) based environments using DRL approach, implemented through Deep Q-Network (DQN), and aiming to maximize Quality of Experience (QoE) while meeting Quality of Service (QoS) constraints. We show through numerical results how limited capacity in Physical Substrate Network (PSN) complicates the training process in terms of finding suitable compromise between performance and convergence. We highlight also how replay buffer may mitigate transient unavailability of PSN nodes and what are the limits of such a solution when the unavailability becomes more prolonged in time or more severe (simultaneous unavailability of more than one node).
A QoE Driven DRL Approach for Network Slicing Based on SFC Orchestration in SDN/NFV Enabled Networks
Lecture Notes in Computer Science, Dec 18, 2023
arXiv (Cornell University), Oct 8, 2016
We propose in this paper a simulation implementation of Self-Organizing Networks (SON) optimizati... more We propose in this paper a simulation implementation of Self-Organizing Networks (SON) optimization related to mobility load balancing (MLB) for LTE systems using ns-3 . The implementation is achieved toward two MLB algorithms dynamically adjusting handover (HO) parameters based on the Reference Signal Received Power (RSRP) measurements. Such adjustments are done with respect to loads of both an overloaded cell and its cells' neighbours having enough available resources enabling to achieve load balancing. Numerical investigations through selected key performance indicators (KPIs) of the proposed MLB algorithms when compared with another HO algorithm (already implemented in ns-3) based on A3 event highlight the significant MLB gains provided in terms global network throughput, packet loss rate and the number of successful HO without incurring significant overhead.
Efficient Answer Extraction of Deductive Databases Modelled by HLPN
ABSTRACT
On concurrency Control in Mutlidatabase Systems with an Extented Transaction Model
HAL (Le Centre pour la Communication Scientifique Directe), 2003
HapiFabric: A Teleconsultation Framework Based on Hyperledger Fabric
Lecture notes in business information processing, 2020
Performance Study of IEEE 802.11 WLAN Integrating QoS requirements
ABSTRACT
BPM 2011 International Workshops, Clermont-Ferrand,France, August 29, 2011, Revised Selected Papers, Part II
HAL (Le Centre pour la Communication Scientifique Directe), Feb 12, 2012
ABSTRACT
Modelling and analyzing home care plans using high-level Petri nets
Given the constant pressure to improve healthcare efficiency, home care appears as a unique solut... more Given the constant pressure to improve healthcare efficiency, home care appears as a unique solution for providing personalized healthcare service and home assistance for a growing number of elderly and chronic patients. Home care plans define the health cares or supportive cares delivered by the different home care professionals for a given patient. The management of these plans is challenging since they are inherently flexible, context dependent and cooperative processes involving repetitive activities with complex temporal expressions. In this paper, we propose a formal method based time recursive ECATNets for modelling and analyzing home care plans. The choice of this formalism relies on its ability in modelling flexible and distributed home care processes, with complex temporal constraints. Moreover, since time recursive ECATNets semantics are expressed in terms of conditional rewriting logic, we can use the Real Time MAUDE TCTL model checker to verify temporal properties of home care plan processes.
Lecture notes in business information processing, 2012
The use of general descriptive names, registered names, trademarks, etc. in this publication does... more The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.
HapiChain: A Blockchain-based Framework for Patient-Centric Telemedicine
Given the exploding number of the elderly and patients with chronic diseases and the uneven distr... more Given the exploding number of the elderly and patients with chronic diseases and the uneven distribution of clinicians, it is economically impossible to continue traditional medicine. Hence, the healthcare sector has been gradually gravitating towards telemedicine, which applies intelligent systems for more comprehensive medical services with minimum costs. The criticality of data and process involved in telemedicine raise various concerns in terms of reliability and security. To this end, in this paper, we propose HapiChain, a blockchain-based framework for patient-centric telemedicine. HapiChain exploits blockchain technology to improve security, scalability, and reliability of medical workflows. Although HapiChain is patient-centric, it also helps the clinicians to save time and prevent unnecessary trips without improvising the level of treatment. In HapiChain, we embed two primary telemedicine services, namely telemonitoring and teleconsultation. For the former service, Hapicare, an existing healthcare monitoring system with self-adaptive coaching using probabilistic reasoning, is used. HapiChain then completes this service by adding teleconsultation services exploiting blockchain technology. The HapiChain framework includes three main layers: (i) interface layer, (ii) DApp layer, and (iii) blockchain layer. In the first layer, Hapicare is used to communicates with the users, i.e., patients and doctors. DApp layer includes the required procedures for security and scalability of HapiChain, namely smart contracts and distributed storage. The latter is achieved using the InterPlanetary File System (IPFS). In the blockchain layer, Ethereum blockchain is used as a platform of DApps. We evaluate the HapiChain framework and the proposed teleconsultation services in a use-case.
IEEE Access, 2019
Resources in a real-world automated manufacturing system may be unreliable, thus paralyzing many ... more Resources in a real-world automated manufacturing system may be unreliable, thus paralyzing many existing deadlock control strategies. This paper defines robust legal markings and proposes a twostep robust deadlock control policy for systems of the simple sequential process with resources based on elementary siphons. The first step, called elementary siphons control, derives a live controlled system without considering resource failures. The second step deals with failure-induced deadlocks control issues. With resource failures taken into account, recovery subnets modeling resource failures and recoveries are added to the first-step-derived system, which may cause the occurrence of failure-induced deadlocks, resulting in an unreliable controlled system. In order to make the system reliable, the definition that a resource failure is observed by a monitor is developed. A scenario is exposed that a resource failure does not need to be observed while can be observed by the added monitors. Arcs connecting recovery places and transitions of the initial system are added based on the obtained scenario. The concept of the extend the adjoint set of a siphon is presented due to a resource failure that needs to be observed while cannot be observed by the added monitors, leading to the modification of the arcs added in the first step. Consequently, a robust controlled system is acquired. Finally, examples are presented to demonstrate the proposed method. INDEX TERMS Automated manufacturing system, Petri net, deadlock prevention, robust control.
IFAC-PapersOnLine, 2018
This paper proposes a performability analysis based on stochastic reward nets (SRNs) of an energy... more This paper proposes a performability analysis based on stochastic reward nets (SRNs) of an energy-efficient server virtualized system (SVS) model handling data-intensive applications and implementing a workload-aware power management (PM) mechanism. The SVS model accounts for workload-aware dependent software aging, unplanned failures and Migrate-VM rejuvenation. We show through numerical analysis of perfomability metrics how workload burstiness and software aging impact SVS behavior in terms of availability and performance.
Advances in Mechanical Engineering, Dec 1, 2018
Business Process Model and Notation is known as a widely used standard for business processes mod... more Business Process Model and Notation is known as a widely used standard for business processes modeling. However, its main drawback is that it lacks formal semantics, leading to some undesirable properties, such as livelocks and deadlocks, such that it creates models with semantic errors. In order to formally verify them, we need to transform it onto a formal language, for example, Petri nets. The approach proposed in this article is an extension of previous approaches stated in the literature by adding probability to gateways and time to transitions. The first aim is to transform the Business Process Model and Notation process diagram onto Petri nets automatically using a developed software package. The developed software package is capable of transforming the XML file of a Business Process Model and Notation process diagram into ''m'' files of a Petri net. The ''m'' files of the Petri net are then coupled with the General Purpose Petri Net Simulator (GPenSIM) for analysis in MATLAB. The second aim is to manually transform the Business Process Model and Notation process diagram using mapping figures onto Petri nets and then analyze it using Timed Petri Net Analyzer tools. The advantage of transforming a Business Process Model and Notation diagram automatically is that we can add time to transitions and probability to gateways. Furthermore, the simulation time can be checked using MATLAB.
Modélisation des workflows collaboratifs à l'aide des ECATNets récursifs
HAL (Le Centre pour la Communication Scientifique Directe), 2008
Design and implementation of a massively parallel ESB
Enterprise Service Bus (ESB) is an SOA-based software architecture for business application integ... more Enterprise Service Bus (ESB) is an SOA-based software architecture for business application integration in distributed and heterogeneous environments. The proposed solutions so commercial as open source offer the same set of basic services such as message transformation, message routing, security. However, none of them take advantage of the multicore/multiprocessor technologies which make plausible the massively parallel processing. In this paper, we describe a new ESB architecture denoted Massively Parallel Application Bus (MPAB) which meets this challenge.
A Secure Data-Sharing Framework Based on Blockchain: Teleconsultation Use-Case
Springer eBooks, Dec 30, 2022
E-health telecommunication systems and networks, 2016
This Staphylococcus epidermidis has been discovered as the most frequent germ detected during ind... more This Staphylococcus epidermidis has been discovered as the most frequent germ detected during indwelling medical devices infection. This fact is well attached with the ability of this bacterium to form structured layered population known as biofilm. Inside S. epidermidis biofilm, bacterial cells present more different behavior than in their planktonic counterpart. This paper describes the thriving application of Petri net theory for modeling of interaction between different regulations actors leading S. epidermidis to switch from Planctonik to Biofilm. Indeed this biologic system is very sensible and has dangerous effect. We propose Agent Petri Nets model to describe and analyze the process of formation of Biofilm molecule. This model presents a formal framework based on Multi Agents system characteristics.
Innovations in Systems and Software Engineering, Feb 4, 2020
This paper deals with the partial order techniques of Petri nets, based on persistent sets and st... more This paper deals with the partial order techniques of Petri nets, based on persistent sets and step graphs methods. To take advantage of the strengths of each method, it proposes the persistent step sets as a parametric combination of the both methods. The persistent step sets method allows to fix, for each marking, the set of transitions S to be covered by the selected steps and then to control their maximal length and number. Depending on the parameter S, it computes covering-steps, persistent sets, persistent-step sets or other kinds of combination of both methods. Moreover, this persistent step selective search preserves, at least, deadlocks of Petri nets. Furthermore, this paper provides two practical computation procedures of the persistent step sets based on the strong-persistent sets and the weak-persistent sets, respectively. Finally, to achieve further reductions, it shows how to weaken the sufficient conditions used in the literature to build persistent sets.