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2012Wassim Ayadi, Ons Maatouk,
Evolutionary Biclustering Algorithm of Gene Expression Data
DEXA Workshops 2012: 206-210, 2012
Abstract
Microarrays represent a new technology for measuring expression levels of several genes under various biological conditions generating multiple data. These data can be analyzed by using biclustering method which aims to extract a maximum number of genes and conditions presenting a similar behavior. This paper proposes a new evolutionary approach to obtain maximal high-quality biclusters of highly-correlated genes. The performance of the proposed algorithm is assessed on synthetic gene expression data. Experimental results show that our algorithm competes favorably with several state-of-the-art biclustering algorithms.
Ameni Azzouz, Meriem Ennigrou, Boutheina JLIFI,Combining tabu search and genetic algorithm in a multi-agent system for solving flexible job shop problem
n International Conference on Enterprise Information Systems (Vol. 3, pp. 47-53), 2012
Abstract
The Flexible Job Shop problem (FJSP) is an important extension of the classical job shop scheduling problem, in that each operation can be processed by a set of resources and has a processing time depending on the resource used. The objective is to minimize the make span, i.e., the time needed to complete all the jobs. This works aims to propose a new promising approach using multi-agent systems in order to solve the FJSP. Our model combines a local optimization approach based on Tabu Search (TS) meta-heuristic and a global optimization approach based on genetic algorithm (GA).
Meriam Jemel, Nadia Ben Azzouna,Towards a scalable and dynamic access control system for web services
In Proceedings of the 8th International conference on Web Information Systems and Technologies(WEBIST 2012), April 18 -21 2012,Porto, Portugal, pages 161-166, 2012., 2012
Abstract
Web services are vulnerable to different types of security attacks. The problem of secure access to web-based
applications is becoming increasingly complex. Management complexity arises because of the scalability
considerations such as the large number of web services users and their invocations and the fact that the
access control system should take into account the context. In this paper we describe the architecture of
our TDRBAC (Trust and Dynamic Role Based Access Control) model which is implemented using agent
technology. In fact, this technology fulfills several requirements of web service’s access control by providing
both context awareness and scalability. In order to verify the scalability of the proposed solution, we expose
some experimental results from a prototype implemented using JADE (Java Agent DEvelopment) platform.
The performance tests show that our TDRBAC multi-agent based system meets the scaling requirements of
large distributed services.Kalthoum Rezgui, Hédia Sellemi,Competency Models: A Review of Initiatives
-, 2012
Abstract
For some years, competency-based learning and training has known a growing interest, especially in conjunction with proliferation of the terms « knowledge society », « citizen mobility », or « globalization ». Competency modeling becomes an important concept in many domains, especially in human resource development and e-Learning. In this paper, we present a review of relevant competency metadata standards and some ontology-based approaches for competency modeling.
Islem Henane, ,Multi-agent based Modeling of the Tunisian Pastoral Dynamic – Multi-level Organization.
Proceedings of the 4th International Conference on Agents and Artificial Intelligence - Volume 1: ICAART, 254–258., 2012
Abstract
astoral systems in arid and semi arid areas are characterized by a continued deterioration. This degradation is the result of the mismanagement of resources in response to natural, economic and social mutations. These systems are considered as complex systems, given the large number of stakeholders in interaction and levels of granularity. To address this situation, analytical and systemic approaches are no longer adequate. In this paper, we propose a multi-agent based model of Tunisian pastoral dynamics taking into account the interaction dynamics of the different stakeholders and the different levels of granularity. The completion of this work is within the scope of the development of the Intelligent Decision Support System PASDES (Pastoral Strategies Definition System). PASDES aims to support pastoral strategic decision making in short and long terms.
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2011, ,
An autonomic registry-based SOA model
EEE International Conference on Service-Oriented Computing and Applications, 2011
Abstract
In the last years, the need for integrating QoS to service oriented architecture (SOA) has become a significant factor for managing service-based systems. In addition, combining self-* and policy-based management has major advantages since it reduces complexity management and effectively drives self-adaptation of Web services. Current service oriented architecture does not support policy-based self-management. In this paper, we present a SOA model based on autonomic registries which are endowed with self-* capabilities. Autonomic registries are in charge of managing their content and collaborating in a federated manner with other autonomic actors in order to maintain service quality, and consequently to participate in the self-adaptation process of executing Web services. The proposed model is combined with a technology that has found popularity and acceptance namely WS-Policy. We extend WS-Policy to represent a rich Web service information model based on QoS data and additional information such as service specific adaptation actions. UDDI is also extended to support policy-based self-management.
Sami Rojbi,User modeling and Web-based customazation techniques: An examination of the published literature
2011 4th International Conference on Logistics, 2011
Abstract
This paper proposes a state of the art of the user modeling and interfaces customization techniques. It presents and discusses techniques intended to be used by application’s designers and also end-user based techniques. It specifies the characteristics modeled in these systems as well as the used technologies.
Wassim Ayadi,Biclustering of microarray data
Algorithms in Computational Molecular Biology: Techniques, Approaches and Applications, John Wiley & Sons, Inc., 2011
Abstract
Biclustering of microarray data
, Lamjed Ben Said,Greedy local improvement of SPEA2 algorithm to solve the multiobjective capacitated transshipment problem
In: Coello, C.A.C. (eds) Learning and Intelligent Optimization. LION 2011. Lecture Notes in Computer Science, vol 6683. Springer, Berlin, Heidelberg., 2011
Abstract
We consider a multi-location inventory system where inventory choices at each location are centrally coordinated through the use of lateral Transshipments. This cooperation between different locations of the same echelon level often leads to cost reduction and service level improvement. However, when some locations face embarrassing storage capacity limits, inventory sharing through transshipment may cause undesirable lead time. In this paper, we propose a more realistic multiobjective transshipment model which optimizes three conflicting objectives: (1) minimizing the aggregate cost, (2) maximizing the fill rate and (3) minimizing the transshipment lead time, in the presence of different storage capacity constraints. We improve the performance of the well-known evolutionary multiobjective algorithm SPEA2 by adequately applying a multiobjective quasi-gradient local search to some candidate solutions that have lower density estimation. The resulting hybrid evolutionary algorithm outperforms NSGA-II and the original SPEA2 in both spread and convergence. It is also shown that lateral transshipments constitute an efficient inventory repairing mechanism in a wide range of system configurations.
Ines Thabet, , ,A Multi-agent Organizational Model for Grid Scheduling
KES-AMSTA 2011: 148-158, 2011
Abstract
Multi-agent technology provides high level organizational concepts (groups, roles, commitments, interaction protocols) to structure, coordinate and ease the adaptation of distributed systems efficiently. This paper proposes to model a grid scheduling system as a multi-agent system organization. The resulting organizational model, based on the Agent Group Role meta-model of Ferber, is evaluated at the conceptual and implementation level. At the conceptual level, we evaluate the efficiency, robustness and flexibility of our model. At the implementation level, the analysis and the evaluation of our proposition, done through simulations, show its efficiency.
