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Search Results: 1 - 10 of 710 matches for " Rachid Boudour "
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Model Transformation for Requirements Verification in Embedded Systems
Rachid Boudour,Mohamed T. Kimour
Asian Journal of Information Technology , 2012,
Abstract: In embedded systems, use cases have become increasingly popular as a means of requirements specification and drive all the development activities,particularly in validation ones. However, they are usually written in informal text form describing the interactions between the environment and the system. This prevents using formal methods in requirements verification. Though, they are becoming a practical means to ensure the correctness of system models, formal methods still are not commonplace in embedded systems especially in the requirements validation. In this study presenst an approach to model transformation for requirements verification in embedded systems. It firstly consists of transforming the use case structured-text style into an UML activity diagram, which may be reused in the subsequent development steps and secondly we transform this diagram into Pres, a formal notation capable of capturing relevant features of embedded systems. In addition to the offered formal verification framework, we argue that our approach enables enriching the use case model and producing more precise and complete requirements.
Effects of Residue Management and Cropping Systems on Wheat Yield Stability in a Semiarid Mediterranean Clay Soil  [PDF]
Rachid Mrabet
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.22022
Abstract: Agriculture is the single biggest user of land and water in Morocco; however its performances are still low due to high rainfall variation and rates of soil productivity depletion. Increasing concerns about soil and environment quality degradation have raised the need to review existing tillage management systems and develop new systems for seed-bed preparation. Consequently, No-tillage is found a promising practice of soil management to improve simultaneously soil quality and wheat production in semiarid Morocco. However, residue management under No-tillage was Not yet studied in conjunction with wheat rotation. Therefore, a field study was conducted in the semiarid Chaouia Plain of Morocco during the period from 1994 to 2003, in order to evaluate the impacts of different tillage practices (conventional tillage (CT), No-tillage (NT)); No-tillage wheat residue management scenarios (total NTr, partial NTp and No-removal of residues NTm) and crop rotations (continuous wheat (CW), Wheat-Fallow (WF), Wheat-Maize-Fallow (WMF), Wheat-Lentil-Fallow (WLF) and Wheat-Barley-Fallow (WBF)) on wheat production. Over-years, conventional tillage system permitted lower yield of wheat while NT maintenance of crop residue at the surface is needed to increase it. Basically, NTp could be adopted in mixed crop-livestock systems of semiarid areas for the purpose of guarantying grain and feed. Wheat yields were the lowest under continuous wheat for all years. Wheat-fallow rotation is an important option in dry years or areas, while wheat-fallow-lentil or barley rotations are recommended in better environments. Stability analysis indicated that yields in the No-tillage system were less influenced by adverse growing conditions than conventional tillage system, particularly under low rainfall. These results indicate that improved soil quality under No-tillage enhanced wheat yield stability by reducing the impact of adverse growing conditions.
SYMTC: Towards a Symbolic Model Checking for the Codesign
R. Boudour,M.T. Kimour
Asian Journal of Information Technology , 2012,
Abstract: The verification of finite-state systems by model-checking often requires to generate (a large part of) the state space of the system under analysis. In this study, we aim at improving the performances of state space construction by using an efficient method to avoid state explosion problem in model checking through the use of-DBM (Difference Bounded Matrices) and on the fly strategy. This approach requires at any time, only the needed states to be in memory and allows for checking several properties, especially, safety, bounded liveness and temporal correctness, which are the most important ones in reactive systems. The specifications are expressed in timed automata and TCTL for the system and properties respectively. The effectiveness of our approach has been demonstrated on many academic examples. The results obtained demonstrate that it is able to verify several properties that could not be checked by other state-of-the-art tools.
A Markov Model for Human Resources Supply Forecast Dividing the HR System into Subgroups  [PDF]
Rachid Belhaj, Mohamed Tkiouat
Journal of Service Science and Management (JSSM) , 2013, DOI: 10.4236/jssm.2013.63023
Abstract:

Modeling the manpower management mainly concerns the prediction of future behavior of employees. The paper presents a predictive model of numbers of employees in a hierarchical dependent-time system of human resources, incorporating subsystems that each contains grades of the same family. The proposed model is motivated by the reality of staff development which confirms that the path evolution of each employee is usually in his family of grades. That is the reason of dividing the system into subgroups and the choice of the superdiagonal transition matrix.

Which Yields with Wastes? Study on Pilot of the Efficiency of Water Treatment Plant— Case of the Sector of Algerian Tanning  [PDF]
Mohamed Necer, Rachid Smail
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.615134
Abstract: Tannery industries generate wastewater containing high concentrations of sulfur. Most of wastes are liquid (effluent). The river section and tanning are the source of most tannery waste. Dehairing is a process of separation of hair and epidermis. Lime and sulfides are used for this process. Thus, sulfur in wastewater dehairing occurs as sulfide. Today, catalysis is at the centre of major societal concerns about energy, environment and sustainable development. The discovery of new catalytic processes and the improvement of existing ones are also critically important for improving the quality of life while simultaneously reducing the adverse impact of human activities on the environment. With a substitution approach of a catalyst MnSO4 by multiple wastes from tannery and the metallurgical sector, this study investigated the recycle of waste from dehairing process and waste from metallurgical industry. The results indicated 32% of oxidized sulfur for the first waste derived from process of depilation and 30% for the second waste from metallurgical process industry. A preliminary cost analysis demonstrated that the proposed solution is much cheaper than the discharging of waste and wastewater in a WWTP; however, the sustainability of the proposed solution provided a second alternative, to alleviate the operational costs of installations wastewater from tanneries, without significantly impacting the environment.
Microstructural Evolution in Terms of Porosity in High-Tc Superconductors
Ahmed Ouari,Mohamed Guerioune,Amar Boudour,Youcef Boumaiza
Asian Journal of Information Technology , 2012,
Abstract: The low critical current densities of high-Tc superconductors materials can be related to the microstructural imperfections such as pores and microcracks which reduce the effective current carrying cross section. The present study examines the characterisation of the state of microstructure and its evolution during thermal treatment of YBa2Cu3O7- . The dilatometric analysis was used to study the shrinkage mechanism during sintering. The microstructure of the sintered samples was characterised in terms of pores distribution and apparent density. Open porosity was measured by mercury porosimeter. In order to compare the results, ultrasonic characterisation such as the longitudinal and transverse wave velocities in the ceramic was carried out. From an ultrasonic point of view, these microstructural features act as inhomogeneities, then the measured ultrasonic parameters will depend on the geometrical arrangement of the microstructure (pores have an effect both on Young s modulus and attenuation).
SYMTC: An Efficient Symbolic Model Checker for Embedded Systems
R. Boudour,M.T. Laskri,M.T. Kimour
Information Technology Journal , 2006,
Abstract: In this study, we aimed at improving the performances of state space construction by using an efficient method to avoid state explosion problem in model checking through the use of-DBM (Difference Bounded Matrices) and on the fly strategy. This approach requires at any time, only the needed states to be in memory and allows for checking several properties, especially, safety, bounded liveness and temporal correctness, which are the most important ones in reactive systems. The specifications are expressed in timed automata and TCTL for the system and properties, respectively. The effectiveness of our approach has been demonstrated on many academic examples. The results obtained demonstrate that it is able to verify several properties that could not be checked by other state-of-the-art tools.
Evaluation of genetic diversity of an algerian durum wheat (Triticum durum Desf.) collection
Boudour Leila,Gherroucha Hocine,Boukaboub Amar,Bouchtab Karima
Journal of Stress Physiology & Biochemistry , 2011,
Abstract: Durum wheat (Triticum durum Desf.) has been extensively cultivated in Algeria for many centuries. During this long period, the species encountered a large diversification implied by the great diversity of climates that led to great genetic diversity of the species. The purpose of this study is to improve the management of phytogenetic resources that can serve as potential breeders for the amelioration of wheat. The study aims at evaluating the diversity of 1019 accessions of durum wheat from different regions of Algeria and which are stored at the Constantine ITGC. The analysis of the results concerning phenological and morphophysiological characters revealed an important intra and intervarietal genetic variability. Subsequently it appeared that the 1019 accessions belong to 19 botanic varieties that differ mainly by the cob, silk and grain colours. Among the characters involved in this study, some appeared to have a direct connection with the adaptation to water stress and thus allowed us identifying the most resistant varieties.
Toward Intelligent Biped-Humanoids Gaits Generation
Nizar Rokbani,Boudour Ammar Cherif,Adel M. Alimi
Computer Science , 2012, DOI: 10.5772/6732
Abstract: In this chapter we will highlight our experimental studies on natural human walking analysis and introduce a biologically inspired design for simple bipedal locomotion system of humanoid robots. Inspiration comes directly from human walking analysis and human muscles mechanism and control. A hybrid algorithm for walking gaits generation is then proposed as an innovative alternative to classically used kinematics and dynamic equations solving, the gaits include knee, ankle and hip trajectories. The proposed algorithm is an intelligent evolutionary based on particle swarm optimization paradigm. This proposal can be used for small size humanoid robots, with a knee an ankle and a hip and at least six Degrees of Freedom (DOF).
Analytical Approach for the Systematic Research of the Periodic Ferroresonant Solutions in the Power Networks  [PDF]
Fathi Ben Amar, Rachid Dhifaoui
Energy and Power Engineering (EPE) , 2011, DOI: 10.4236/epe.2011.34056
Abstract: Ferroresonance is a complex and little known electrotechnical phenomenon. This lack of knowledge means that it is voluntarily considered responsible for a number of unexplained destructions or malfunctioning of equipment. The mathematical framework most suited to the general study of this phenomenon is the bifurcation theory, the main tool of which is the continuation method. Nevertheless, the use of a continuation process is not devoid of difficulties. In fact, to continue the solutions isolats which are closed curves, it is necessary to know a solution belonging to this isolated curve (isolat) to initialise the continuation method. The principal contribution of this article is to develop an analytical method allowing systematic calculation of this initial solution for various periodic ferroresonant modes (fundamental, harmonic and subharmonic) appearing on nonlinear electric system. The approach proposed uses a problem formulation in the frequency domain. This method enables to directly determine the solution in steady state without computing of the transient state. When we apply this method to the single-phase ferroresonant circuits (series and parallels configurations), we could easily calculate an initial solution for each ferroresonant mode that can be established. Knowing this first solution, we show how to use this analytical approach in a continuation technique to find the other solutions. The totality of the obtained solutions is represented in a plane where the abscissa is the amplitude of the supply voltage and the ordinate the amplitude of the system’s state variable (flux or voltage). The curve thus obtained is called “bifurcation diagram”. We will be able to then obtain a synthetic knowledge of the possible behaviors of the two circuits and particularly the limits of the dangerous zones of the various periodic ferroresonant modes that may appear. General results related to the series ferroresonance and parallel ferroresonance, obtained numerically starting from the theoretical and real cases, are illustrated and discussed.
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