Zaki Brahmi

Zaki Brahmi
University of Sousse | ISTLS · Department of Computer Science

PhD

About

68
Publications
19,117
Reads
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258
Citations
Introduction
Computer Science Assistant Professor ( Sousse University), Cloud computing, web service, scientific workflow and data stream mining.
Additional affiliations
September 2017 - present
Taibah University
Position
  • Professor (Assistant)
September 2012 - September 2017
University of Sousse
Position
  • Professor (Assistant)
September 2011 - present
University of Sousse
Position
  • Asistant prof.
Education
September 2006 - December 2010
University of Tunis El Manar
Field of study
  • Computer Science

Publications

Publications (68)
Conference Paper
Full-text available
Cloud computing has become a dominating trend in the IT industry and academia. In recent years, many Cloud providers have emerged in the market, each one has proper standards and service interface. Migration of legacy systems and their data to a Cloud platform or moving applications from one Cloud provider to another are complicated and high cost p...
Article
Full-text available
The rapid evolution of technology has led to the generation of high dimensional data streams in a wide range of fields, such as genomics, signal processing, and finance. The combination of the streaming scenario and high dimensionality is particularly challenging especially for the outlier detection task. This is due to the special characteristics...
Conference Paper
Full-text available
Recently, another cloud taxonomy service in addition to IaaS, PaaS and Saas services has been added: this is the business process as a service in the cloud (BPaaS). A BPaaS is any business process delivered through a cloud service model via internet with access through web interfaces. Therefore, process models will be developed by providers for dis...
Article
Full-text available
With the appearance of the COVID-19 pandemic, the practice of e-learning in the cloud makes it possible to: avoid the problem of overloading the institutions infrastructure resources, manage a large number of learners and improve collaboration and synchronous learning. In this paper, we propose a new e-leaning process management approach in cloud n...
Data
In multi-agent recommender system, the knowledge degree of an agent and its trust degree are two main criteria in the decision-making phase. These criteria are used to recommend the expert agent. Therefore, how to model agent and evaluate its trust is becoming a challenging issue. This problem can affect the whole prediction of expert agents. In th...
Chapter
Full-text available
It is worth to mention that nowadays we observe an evolving interest for the acquisition and the exploitation of new technologies in the context of learning specifically the Internet. They are based on the use of approaches with diverse functionalities (e-mail, Web pages, forums, LMS, and so on) as a support of the process of teaching-learning. E-l...
Article
Full-text available
Cloud Computing (CC) proposes a multi-tenant framework used by multiple concurrent users, each of which exhibits different and varied behavior. Such heterogeneity shapes a highly fluctuating load and creates new usage patterns overtime at the server level. Virtual Machines (VMs) interference also plays a big part in inducing changes at server load....
Conference Paper
Full-text available
Cloud Computing (CC) enables client-server relationship in order to release users from computational and storage responsibility. As multi-tenant environment, Cloud providers are dealing, in one hand, with multiple concurrent users each of which exhibits a different and variable behavior over time and in the other hand, with a performance interferen...
Article
Full-text available
Intensive workflows require a lot of computational resources and massive data movement between Storage and Computing Servers hosting these datasets and tasks. Moving these datasets among these servers may increase the execution time, generate a high-energy consumption by communication devices and a �significant data movement. In this paper, we prop...
Conference Paper
Full-text available
Intensive workflows require a lot of computational resources and massive data movement between Storage and Computing servers hosting these datasets and tasks. Moving these datasets among these servers may increase the execution time, generate a high energy consumption by communication devices and a significant data movement cost. Thus, we need a go...
Article
Full-text available
Abstract: Cloud computing paradigm has been a trend in the computational world. Thus, many service providers today are competing to enhance their features to attract more customers as they are offering them a bunch of features through a pay-as-you-go pricing model. However, despite their huge fame, cloud environments still suffer from some issues t...
Chapter
Full-text available
In order to maintain energy efficiency and optimize resource utilization in cloud datacenters, cloud providers adopt virtualization technologies as well as server consolidation. Virtualization is the means used to achieve multi-tenant environments by creating many virtual machines (VMs) on the same physical machine (PM) in a way that they share sam...
Conference Paper
Cloud computing has become a dominating trend in the IT industry and academia. In recent years, many Cloud providers have emerged in the market, each one has proper standards and service interface. Migration of legacy systems and their data to a Cloud platform or moving applications from one Cloud provider to another are complicated and high cost p...
Conference Paper
Full-text available
Abstract—Cloud computing is a model that allows users to rent the services they want, in real time, and pay as they go. Thanks to virtualization, Cloud infrastructure exploitation will be easier and smoother because it offers many benefits to data center administrators and end users. The main goal of virtualization is to share the infrastructure be...
Conference Paper
Full-text available
Cloud Computing is becoming popular model for delivering Information Technology (IT) that offers different services on demand over the Internet. This technology is dedicated to distribute computing resources and their consumption as software services. With the availability of data gathered from sophisticated scientific tools, workflows have proven...
Conference Paper
Full-text available
Cloud computing is a model that allows users to rent the services they want, in real time, and pay as they go. Thanks to virtualization, Cloud infrastructure exploitation will be easier and smoother because it offers many benefits to data center administrators and end users. The main goal of virtualization is to share the infrastructure between use...
Conference Paper
Full-text available
Cloud Computing paradigm has been a trend in the computational world. Thus, many service providers today are competing to enhance their features and attract more customers as they are offering them a bunch of services through a pay-as-you-go pricing model. However, despite their huge fame, cloud environments still suffer from some issues that are b...
Conference Paper
Full-text available
In order to maintain energy efficiency and optimize resource utilization in cloud datacenters, cloud providers adopt virtualization technologies as well as server consolidation. Virtualization is the means used to achieve multi-tenant environments by creating many virtual machines (VMs) on the same physical machine (PM) in a way that they share sam...
Chapter
Full-text available
Cloud computing plays a vital role in distributed systems used by Internet users. It provides a flexible environment in which data, equipment and services can be shared among end users in order to save time and cost. Cloud service composition is still one of the most important issues related to this paradigm. Indeed, Dynamic Cloud Service Compositi...
Conference Paper
Full-text available
As a consequence of the massive adoption of internet, many platforms such as Moodle, WebCT and Claroline aim to ease and improve the teaching/learning process by means of taking advantage of internet technologies. However, available systems do not satisfy all the needs of different institutions/teachers, which push them to develop their own systems...
Conference Paper
Full-text available
Distance learning is an area in progress that continues to evolve with further research. In this context, a big attention is given by researchers, developers and educators to the collaborative learning through Learning Management Systems (LMS), especially through learning environments and social networking. However, since collaboration and interact...
Conference Paper
Full-text available
In multi-agents recommender systems, agents interact with each other to provide an efficient recommendation to the end user. Trust is, therefore, important to make these interactions useful. In an open, heterogeneous and dynamic multi-agent environment, it is difficult for agents to assess and establish trusting relationships for cooperation. Thus,...
Article
Full-text available
Workflows management systems (WfMS) are aimed for designing, scheduling, executing, reusing, and sharing workflows in distributed environments like the Cloud computing. With the emergence of e-science workflows, which are used in different domains like astronomy, life science, and physics, to model and execute vast series of dependents functionalit...
Conference Paper
Full-text available
The cloud computing is the dream of computing used as utility that became true. It is currently emerging as a hot topic due to the important services it provides. Ensuring high quality services is a challenging task especially with the considerable increase of the user's requests coming continuously in real time to the data center servers and consu...
Conference Paper
Full-text available
The cloud computing is the dream of computing used as utility that became true. It is currently emerging as a hot topic due to the important services it provides. Ensuring high quality services is a challenging task especially with the considerable increase of the user's requests coming continuously in real time to the data center servers and consu...
Conference Paper
Undoubtedly, Cloud computing is the ongoing trends that robbed the widespread concern. In fact, it succeeded in discharging users from computational and storage burden to o�er them as services following pay-as-you-go principle. The substantial feature of Cloud is the ability to scale up with the rise of user demands. However, Cloud performance fall...
Article
Full-text available
Cloud computing is an economical solution for industry which is highly scalable and useful of virtualized resources that can be used on demand. It will have a significant impact on companies with the introduction of orchestration platforms as a Service (OaaS) to perform the services that support a variety of business processes such as BPEL. It's be...
Conference Paper
In a Cloud Computing environment, a pool of resources in multiple physical machines is shared among virtual machines. Those virtual machines are deployed to host client applications and communicate together to run the appropriate tasks. Therefore communication between VMs should be taken into consideration when allocating VMs across servers. Recent...
Conference Paper
Full-text available
Generally, extracting only expected knowledge from data is not su�cient since unexpected ones can hide useful information concerning the data behavior. These information can be further used to optimize the current state. We are talking about outlier detection. It's a data mining task aiming to �nd abnormal points or sequence of data hidden in the d...
Conference Paper
Full-text available
In recent years, the rapid proliferation of enormous sources of digital data and the development of Cloud Computing have led to greater dependence on data-intensive services. Each service may actually request or create a large amount of data sets. The scope, number, and complexity of data-intensive services are all set to soar in the future. Theref...
Conference Paper
Full-text available
Massive data applications such as E-science applications are characterized by complex treatments on large amounts of data which need to be stored in distributed data centers. In fact, when one task needs several datasets from different data centers, moving these data may cost a lot of time and cause energy’s high consumption. Moreover, when the num...
Conference Paper
Energy consumption is emerging as a new crucial issue of the Cloud Computing environments such as data centers.The problem of power consumption is more challenging especially in the context of Scientific workflows deployment in the Cloud as they trigger intensive computational tasks and data manipulation steps which begets excessive data movement o...
Conference Paper
Full-text available
In a highly dynamic and decentralized environment, where data are uncertain, Trust has become a key factor in the process of decision making. Trust-based recommendation is based on Trust between users. It was the main subject of several studies such as: [10, 12, 15, 24]. In fact, for relevant recommendation, it is very important to define the adequ...
Conference Paper
Full-text available
The Cloud computing forges the shape of the current era and the following ones based on delocalized IT infrastructure and sharing resources. However, the rebellious rise of cloud computing comes with concerns over energy consumption. Numerous reports which inspected Cloud energy consumption showed that the Cloud is an energy monster, specifically t...
Conference Paper
Full-text available
Cloud Computing has emerged as a service model that enables on-demand network access to a large number of available virtualized resources and applications with a minimal management effort and a minor price. The spread of Cloud Computing technologies allowed dealing with complex applications such as Scientific Workflows, which consists of a set of i...
Conference Paper
Full-text available
Cloud Computing has emerged as a service model that enables on-demand network access to a large number of available virtualized resources and applications with a minimal management effort and a minor price. The spread of Cloud Computing technologies allowed dealing with complex applications such as Scientific Workflows, which consists of a set of i...
Thesis
Full-text available
Le Cloud Computing est un terme relativement récent, fondé sur des décennies de recherche scientifique en matière de virtualisation et d’informatique distribuée. Le Cloud devient un contributeur précieux, et économique pour les entreprises avec l’introduction des plateformes d’orchestration comme étant un service cloud "Orchestration as a service"...
Conference Paper
Full-text available
The Software as a Service provides complete software systems. SaaS is known as «on-demand software». In the Cloud Computing, Business Process Execution Language (BPEL) is widely used in SaaS application development. BPEL is the de facto standard for business process modeling in today's enterprises and is a promising candidate for the integration of...
Conference Paper
Full-text available
The advantages of Cloud computing, such as cost effectiveness and ease of management, encourage more and more companies to adapt its services. Within this wide and distributed environment, a single Cloud service, on its own, cannot satisfy all the user's requirements. Therefore, the combination of several service functionalities is crucial. This op...
Conference Paper
Full-text available
The decentralized execution of a BPEL process is done by partitioning a BPEL process into a set of BPEL sub-processes; each of them is committed to perform a part of the BPEL process. All the BPEL sub-processes must be coordinated to perform the overall Process execution. The BPEL partitioning program is an optimization problem with a high-dimensio...
Conference Paper
Full-text available
Mobile Agent (MA) is an autonomous entity that can move from a host to another under self-control. It's a technology for distributed system computing and communication. Although, it creates serious theo- retical and practical problems like heterogeneity, preservation of commu- nication, shared resource management and particularly security problem t...
Conference Paper
Full-text available
In our days, the cloud computing wins a great importance. So it becomes the refuge of many companies especially Small and Medium sized enterprises (SMEs), since it provides computer services witch fits with demand and charged according to their use. Now the evolution towards the cloud is promoting that orchestration business process to be run as a...
Conference Paper
Full-text available
Cloud Computing is emerging today as a service model used to relocate locally-based data and applications to virtualized services available via Internet at a lower cost. A key to exploit the benefits of this model is orchestration which consists in coordinating effectively the deployment of a set of virtualized services in order to fulfill operationa...
Data
Full-text available
Conference Paper
Full-text available
The Model Driven Engineering (MDE) has been proposed to support the development, maintenance and evolution of software systems. In this context several approaches for transformation models have been proposed in the literature. They suffer from two major limitations: i) they have been tested on homogeneous metamodels (e.g., Ecore, UML, Minjava, Kerm...
Article
Full-text available
Automatic Web Service Composition (AWSC) is the processes of combining a chain of connected atomic servicestogether in order to create a more complex and value-added composite service. To differentiate web services which have the same functionalities, Quality of Service (QoS) has been mostly applied. Given a high dynamicity and a rapid growth in th...
Article
Full-text available
A major challenge in the field of multi-agent systems is to enable autonomous agents to allocate tasks efficiently. In the context of massive multi-agents system (MMAS) which is characterised by a large number of dynamic and heterogeneous agents, traditional tasks allocations approaches based on the negotiation between agents, or a single allocator...
Conference Paper
Full-text available
A major challenge in the field of Multi-Agent Systems is to enable autonomous agents to allocate tasks efficiently. In previous work, we have developed a decentralized and scalable method for complex task allocation for Massive Multi-Agent System (MMAS). The method was based on two steps: 1) hierarchical organization of agent groups using Formal Co...
Conference Paper
Full-text available
Decentralized orchestration offers performance improvements in terms of increased throughput and scalability and lower response time. However, decentralized orchestration also brings additional complexity to the system, mainly, in terms of exception handling. The research presented in this paper is carried out on the basis of some previous work of...
Article
Full-text available
Task allocation is still a fundamental problem in Multi-Agents System (MAS). It allows coalition formation of agents in order to cooperate together to perform a complex task. In general, the task allocation process includes two steps: i) finding the set of agents that can, potentially, participate to task allocation process, ii) computing the optim...
Conference Paper
Full-text available
A major challenge in the field of Multi-Agent Systems is to enable autonomous agents to allocate tasks efficiently. In previous work, we have developed a decentralized and scalable method for complex tasks allocation for Massive Multi-Agent System (MMAS) based on two steps: 1) hierarchical organization of agent groups using Formal Concepts Analysis...
Article
Full-text available
Task allocation is still a fundamental problem in Multi-Agents System (MAS). It allows coalition formation of agents in order to cooperate together to perform a complex task. In general, the task allocation process includes two steps: i) finding the set of agents that can, potentially, participate to task allocation process, ii) computing the optim...
Article
Full-text available
Task allocation is still a fundamental problem in Multi-Agents System (MAS). It allows the formation a coalition of agents to cooperate together in order to carry out a complex task. Generally, the process of task allocation requires calculating the value of all the possible allocations, then determining which optimal. In the context of Massive Mul...

Questions

Questions (20)
Question
I have a question regarding Researchgate, I have noticed that my score for a few months is almost fixed although the number of citation of my papers has increased ??
Question
I need a response about comparison between Binary representation and real representation in numerical optimization
Question
Hello,
I would like to evaluate a solution for truthful web services composition. Any help about DataSet/Benchmark and evaluation metrics.
Thkx
Question
I need help with a real intensive data workflow. Indeed, I need an example of workflow whose data used by its tasks can change in term of size.
thkx
Question
Hi
I'need to know if exist an data transfer cost model in multi-cloud computing environment. Majority of papers, use: size(dataset) / bandwith, but when you lock for google (for example), it's not the same.
Any proposition ?
Question
Any document or help !!
Question
Hi all
I need to know hwo to compute the position of the prey ???
if the solution is a set of objects So what is the position of a wolf ?
best regards
Question
I need to know if there is a simulator for interference between VMs runing in the same Pysical Machine ?