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Complex Object Shapes Recognition. Automatic Aid Photointerpretation in a Satellite Image

International Journal of Geosciences 2012年第1期3卷 21-24页

作者： Kada Mouedden youcef amar Macho Anani Sara Lebid Mohammed Benyahia Department of Electronics Faculty of Engineering Sciences Djillali Liabes University of Sidi Bel Abbes Sidi Bel Abbes Algeria

The interpretation of geological structures on earth observation images involves like many other domains to both visual observation as well as specialized knowledge. To help this process and make it more objective, we propose a method to extract the components of complex shapes with a geological significance. Thus, remote sensing allows the production of digital recordings reflecting the objects’ brightness measures on the soil. These recordings are often presented as images and ready to be computer automatically processed. The numerical techniques used exploit the morphology ma- thematical transformations properties. Presentation shows the operations’ sequences with tailored properties. The example shown is a portion of an anticline fraction in which the organization shows clearly oriented entities. The results are obtained by a procedure with an interest in the geological reasoning: it is the extraction of entities involved in the observed structure and the exploration of the main direction of a set of objects striking the structure. Extraction of elementary entities is made by their physical and physiognomic characteristics recognition such as reflectance, the shadow effect, size, shape or orientation. The resulting image must then be stripped frequently of many artifacts. Another sequence has been developed to minimize the noise due to the direct identification of physical measures contained in the image. Data from different spectral bands are first filtered by an operator of grayscale morphology to remove high frequency spatial components. The image then obtained in the treatment that follows is therefore more compact and closer to the needs of the geologist. The search for significant overall direction comes from interception measures sampling a rotation from 0 to 180 degrees. The results obtained show a clear geological significance of the organization of the extracted objects.

关键词： Object Shapes Recognition Photointerpretation

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Temperature Variations in Sidi Bel Abbes during the Last Three Decades

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Journal of Environmental Science and Engineering(B) 2012年第5期1卷 690-694页

作者： Sara Lebid youcef amar Macho Anani Benyounes Djahed KadaMouedden Christian Mathieu Green Laboratory Djillali Liabes University ofSidi Bel A bbes Sidi Bel A bbes 22000 AIgeria Faculty of Sciences Jean Perrin. Artois University Lens Cedex 62000 France

The Mediterranean climate of the Sidi Bel Abbes city in northwestern Algeria has not been the subject of many investigations except some sporadic syntheses reports. However, climate change studying its most important parameters has not, at our knowledge, been the subject of a rigorous study. For this purpose this work intends to gather several temperatures ranging between 1980 and 2006 and find a mathematical model that tells us climate changes following changes in temperature during this time interval. Consequently and undesirably, the results confirm firmly the global greenhouse effect affecting our planet, but what seems rather puzzling is the fact that this warming trend has accelerated over time resulting in a changing climate toward warmer periods, for that reason a likely shift in the region of a semi-arid to tropical or arid regime overall, depending mainly on the evolution of the Azores anticyclone.

关键词： Climate temperature heat quantity global warming greenhouse effect.

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Impact of Industrial Pollution on the Zooplankton Population Diversity of the Hammam Boughrara Dam

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Journal of Environmental Science and Engineering(A) 2012年第4期1卷 527-532页

作者： youcef amar Benyounes Djahed Sara Lebid Macho Anani Kada Moueddene Christian Mathieu GREEN Laboratory Djillali Liabes University Sidi Bel Abbes 22000 Algeria Jean Perrin Science Faculty Artois University Lens 62300 France

Works concerning zooplankton of freshwaters of the western area of Algeria are only very fragmentary and remain at an embryonic state. Remediating to this situation, it led a study of the biodiversity and zooplanktonic populations distribution in time and space in the Boughrara dam lake which remains subject to a strong pollution coming essentially from Morocco. The preliminary results of the faunistic analysis of the zooplanktonic populations enabled to highlight an important richness of zoological groups. The CFA （correspondences factorial analysis） and the AHC （ascending hierarchical classification） methods used both enabled to define the species distribution of both open waters and littoral ones, and also to perform existing affinities between them and the state of the used medium. Compared to other barrages, such as those of Bouhanifia and of Sarno, the zooplanktonic populations of both open waters and littoral populations appear to a great extent numerous in rain period. On the quantitative and qualitative level, the zooplanktonic populations strongly suffer from the pollution contamination coming from the Mouillah River especially in summer period. It is time to think about the protection of this fauna which is the second trophic chain link and this intending to preserve the ecosystems in an equilibrium state and to consider the exploitation of natural resources in the realization of an aquacultural farm.

关键词： Biodiversity faunistic analysis pollution zooplanktonic populations.

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Attenuation of Rayleigh Surface Waves in a Porous Material

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Chinese Physics Letters 2012年第4期29卷 123-125页

作者： DEBBOUB Salima BOUMAIZA youcef BOUDOUR amar TAHRAOUI Tarek Laboratory of Materials Elaboration and Analysis Department of PhysicsFaculty of SciencesUniversity of AnnabaP.O.BOX 1223000 AnnabaAlgeria

Using acoustic microscopy at higher frequency,we show the velocity evolutions of surface acoustic waves,in particular Rayleigh waves that depend on porosity for a mesoporous silicon *** velocities are obtained from different V(z) curves,which are determined experimentally at a frequency of *** analysis of V(z) data yields attenuation that is directly dependent on *** the other hand,αN attenuation has been modeled and allows us to investigate its influence on the velocity VR of the propagation for Rayleigh waves.

关键词： layer porosity Porous

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OPTIMAL CONTROL OF AN M/G/1 RETRIAL QUEUE WITH VACATIONS

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 487-502页

作者： amar AISSANI University of Science & Technology Houari Boumediene BP 32 El Alia Bab-Ez-Zouar 16111Algeria

In this note, we consider an M/G/1 retrial queue with server vacations, when retrial times, service times and vacation times are arbitrary distributed. The distribution of the number of customers in the system in stationary regime is obtained in terms of generating function. Next, we give heavy traffic approximation of such distribution. We show that the system size can be decomposed into two random variables, one of which corresponds to the system size of the ordinary M/G/1 FIFO queue without vacation. Such a stochastic decomposition property is useful for the computation of performance measures of interest. Finally, we solve simple problems of optimal control of vacation and retrial policies.

关键词： Retrial queues vacation optimal control stochastic decomposition ageing distribution heavy traffic

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Finite element analysis of slope stability by expanding the mobilized principal stress Mohr's circles-Development, encoding and validation

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1165-1179页

作者： Djillali amar Bouzid Department of Civil Engineering Faculty of TechnologyUniversity of Blida 1Blida09000Algeria

In recent years,finite element analysis is increasingly being proposed in slope stability problems as a competitive method to traditional limit equilibrium methods(LEMs)which are known for their inherent ***,the application of finite element method(FEM)to slope stability as a strength reduction method(SRM)or as finite element limit analysis(FELA)is not always a success for the drawbacks that characterize both *** increase the performance of finite element analysis in this problem,a new approach is proposed in this *** consists in gradually expanding the mobilized stress Mohr’s circles until the soil failure occurs according to a prescribed non-convergence *** present approach called stress deviator increasing method(SDIM)is considered rigorous for three main ***,it preserves the definition of the factor of safety(FOS)as the ratio of soil shear strength to the mobilized shear ***,it maintains the progressive development of shear stress resulting from the increase in the principal stress deviator on the same plane,on which the shear strength takes ***,by introducing the concept of equivalent stress loading,the resulting trial stresses are checked against the violation of the actual yield criterion formed with the real strength parameters rather than those reduced by a trial *** new numerical procedure was encoded in a Fortran computer code called S^(4)DINA and verified by several *** with other numerical methods such as the SRM,gravity increasing method(GIM)or even FELA by assessing both the FOS and contours of equivalent plastic strains showed promising results.

关键词： Slope stability,Finite element analysis Strength reduction method(SRM),Stress point-based factor of safety(FOS),Limit equilibrium method(LEM),Stress deviator Mohr’s circle,Plastic strain

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THE LERAY-SCHAUDER CONDITION FOR 1-SET WEAKLY-CONTRACTIVE AND(ws)-COMPACT OPERATORS

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Acta Mathematica Scientia 2014年第2期34卷 263-273页

作者： Afif BEN amar Department of Mathematics Faculty of Sciences

Abstract The main purpose of this article is to prove a collection of new nxea point theorems for （ws）-compact and so-called 1-set weakly contractive operators under Leray- Schauder boundary condition. We also introduce the concept of semi-closed operator at the origin and obtain a series of new fixed point theorems for such class of operators. As consequences, we get new fixed point existence for （ws）-compact （in particular nonexpansive） self mappings unbounded closed convex subset of Banach spaces. The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness. Later on, we give an application to generalized Hammerstein type integral equations.

关键词： Measure of weak noncompactness weakly condensing and weakly nonexpan-sire (ws)-compact operator fixed point theorems semi-closed at the origin

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Are environment-related technologies key to unlock the path towards sustainable development:An econometric analysis

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Geoscience Frontiers 2024年第4期15卷 437-448页

作者： amar Rao Satish Kumar School of Management BML Munjal UniversityGurugramHaryanaIndia Indian Institute of Management Nagpur India

The objective of this study is to investigate the correlation between energy intensity and environmentrelated technology in industrialized *** utilizing panel data from 23 countries over a span of 32 years(1990-2021),this research aims to contribute to the comprehension of the role of green innovation in sustainable *** study employs the Stochastic Impacts by Regression on Population,Affluence,and Technology model while controlling for variables including population growth,gross domestic product in purchasing power parity,Information and Communication Technology capital deepening,renewable energy consumption,and green innovation represented by research and development expenditure on environment-related *** results of the analysis,employing panel unit root tests,cross-sectional dependence tests,and a Method of Moments quantile regression,reveal that green innovation has a positive influence on diminishing energy intensity,with a more substantial impact at higher ***,ICT capital deepening is determined to have a positive and noteworthy effect on reducing energy *** findings of this study offer valuable insights for policymakers in their endeavours to accomplish sustainable development goals.

关键词： Technology Sustainable development Energy intensity Quantile regression

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Nonlinear ion-acoustic solitary waves in an electron-positron-ion plasma with relativistic positron beam

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Chinese Physics B 2018年第10期27卷 471-476页

作者： Ridip Sarma amar P Misra Nirab C Adhikary Department of Mathematics University of Science and TechnologyTechno CityKhanaparaBaridua9th MileRi-BhoiMeghalayaIndia Department of Mathematics Siksha BhavanaVisva-Bharati University Physical Sciences Division Institute of Advanced Study in Science and TechnologyVigyan PathPaschim BoragaonGarchukGuwahati-781035AssamIndia

The propagation characteristics of nonlinear ion–acoustic（IA） solitary waves（SWs） are studied in thermal electron–positron–ion plasma considering the effect of relativistic positron beam. Starting from a set of fluid equations and using the reductive perturbation technique, we derive a Korteweg–de Vries（KdV） equation which governs the evolution of weakly nonlinear IA SWs in relativistic beam driven plasmas. The properties of the IA soliton are studied, and it is shown that the presence of relativistic positron beam significantly modifies the characteristics of IA solitons.

关键词： electron-positron-ion plasma relativistic effect ion-acoustic wave homogeneous balance method

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CFD simulation of homogeneous reaction characteristics of dehydration of fructose to HMF in micro-channel reactors

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1340-1349页

作者： Xin Zhang Hui Liu amar Samb Guofeng Wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical Technology Beijing 100029 China China Tianchen Engineering Corporation (Beijing Branch) Beijing 100029 China

In this work the applicability of the micro-channel reactor technique to the production of promising platform chemical 5-hydroxymethyl furan(HMF) from fructose in aqueous solution is systemically investigated by performing CFD *** factors including solvents,residence time distribution of reaction mixtures,heat transfer conditions and micro-channel configurations are evaluated in terms of the reaction performance indices,i.e.,conversion of fructose,HMF selectivity and yield.A scale-up method from a single channel to a multiple channel reactor is also *** is demonstrated that:1) at the single channel scale,controlling residence times and temperature distribution of the reaction mixture within the channel is crucial for enhancing the reaction performance,while different channel configurations lead to marginal improvements;2) for the scaling-up of the reaction process,a reactor module containing 15 circular parallel channels could be used as module blocks,which can be stacked one by one to meet the required reactor performance and production *** present results show that micro-reactors are quite suitable for HMF production.

关键词： Fructose dehydration Micro-channel reactor Simulation Optimization

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