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The Floristic Diversity of the Tlemcen Southern Slope Scrublands （Western Algeria）

Journal of Life Sciences 2012年第10期6卷 1167-1173页

作者： Belhacini Fatima bouazza mohammed Laboratory of Ecology and Management of the Natural Ecosystems Department of Ecology and Environment University Abou BakrBelkaid Tlemcen 13000 Algeria

This work was completed on the study of the southern slope scrublands （matorrals） of Tlemcen region in the northwest of Algeria （Western Algeria）. These scrublands are under various states of degradation, made up of Quercus ilex, Juniperus oxycedrus, Thymus ciliatus, Rosmarinus officinalis. The problems sought in this study are to give the actual position of vegetable cover and in particular that of the formations to matorrals currently existing in the southern slope of the area of Tlemcen, while being based on the phytoecological aspect of the vegetable groupings which constitute this inheritance. Sampling is the first phase of work based on the analysis of the spatial variations of the structure and composition floristic and considering the nature of the problem to be treated, the authors considered to be useful to use the method Zuricho Montpeli6raine developed at the point by Braun-Blanquet, the method usually used consists to collect all the plant species and to make the list of the species on a small square of surface 100 m2 （have it minimal）. The floristic readings （150 on the whole） were taken according to the method of Braun-Blanquet. Our results show that there exists a therophytisation marked by a general invasion of annual species as show us as the synergistic action of the aridity and the anthropic action generated important modifications on the level of the vegetation in the dynamic direction. This advanced degradation leads a steppisation which results in a substitution of the elements of the matorrals by species more adapted much the xericity.

关键词： Scrublands floristic diversity phanerophyte chamaephyte anthropical Tlemcen Algeria.

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Note on the Orchids of the Moutas Hunting Reserve--- Tlemcen （Western Algeria）

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Journal of Life Sciences 2013年第4期7卷 410-415页

作者： Brahim Babali Abderrahmane Hasnaoui mohammed bouazza Laboratory of Ecology and Management of the Natural Ecosystems Department of Ecology and Environment Aboubakr BelkaidUniversity Tlemcen 13000 Algeria

Through the Algerian orchid flora, several rare species remain endemic in the Maghreb. This note on the orchids will enrich the already existing data on the area of Tlemcen. Currently, the coexistence of orchids and species （such as Quercus faginea subsp. tlemcenensis （DC.） M., Lonicera implexa L. and Ruscus aculeatus L.） indicates an ecological environment of dominant forest. Nevertheless, the significant frequency of fires and human pressure is leading to erosion of this area orchids richness. This work enabled us to establish a complete inventory of the orchids species that exist, with an estimate of the populations and a taxon illustration for each of them. Fourteen species （14） were indexed, during the period of spring 2011 only, in this reserve and the scoured areas which do not exceed 2000 ha, representing 29% of the total Algerian orchids species. Among the rare taxa signed ourselves： Ophrys subfusca subsp. battandieri （Rchb.） Batt. and Dactylorhiza durandii （Boiss. and Reuter） M. Lainz in Oranie （O）＊

关键词： Biodiversity orchidaceae mounts of Tlemcen moutas Ophrys Dactylorhiza rare species inventory.

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The current state of the plant diversity in the Tlemcen region(Northwest Algeria)

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Open Journal of Ecology 2012年第4期2卷 244-255页

作者： Smain El-Amine Henaoui mohammed bouazza Department of Biology and Environment Faculty of Natural Sciences and Life and Earth Sciences and the UniverseUniversity of TlemcenTlemcenAlgeria

Tlemcen region is characterized by a Mediterranean climate, with a remarkable vegetal cover. The latter is influenced by the anthropozoological action. For that, we realized a phytoecological study based on the minimum area classical method [1] which allows us to have a good overview on plant biodiversity and better analyze and interpret the vegetation at different levels (systematic composition;biological, morphological and biogeographical characterizations;stratification;and plant species inventory which we hope comprehensive). The results show that our ecosystems are disrupted because therophytisation, before last vegetation dynamics element [2], settles giving up a few feet of cork and holm oaks species of ancient forest.

关键词： Phytoecology Plant Diversity Minimum Area Anthropic Action Tlemcen(Western Algeria)

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The Bioclimate in the Steppe of Tlemcen （Oran, Western Algeria）

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Journal of Life Sciences 2013年第3期7卷 313-321页

作者： Assia Bekkouche Fouzia Ayache mohammed bouazza Department of Biology Faculty of Science University Abou Bakr Belkaid Tlemcen 13000 Algeria

The last decade was marked by the special interest in flora, biological characteristics, its adaptation to climate fluctuations and the influence of human activities. The steppe climate is generally characterized by its heterogeneity. The lower semi-arid： 300 mm to 400 mm per year; The arid higher： 200 mm to 300 mm per year; The arid lower： between 100 mm and 200 mm per year. Its wide analysis of a region is based on data provided by weather stations; a summary of the climate study area was analyzed with representative stations （Ain Sefra, El Aricha, Ras el-Ma, Saf-Saf）. This steppe is in various states of degradation, consisting of Stipa tenacissima, Artemisia herba alba, Biscutella didyma, Spartium junceum and Lepidium glastifolium, etc..

关键词： Bioclimate steppe Algeria the semi-arid ombrothermiques diagrams.

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Band Structure and Electron Transport of Bulk Based on an Ensemble Monte Carlo Calculation

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Journal of Environmental Science and Engineering(B) 2012年第12期1卷 1291-1296页

作者： Hichem mohammed Tahir Benyounes bouazza Noredine Massoum Department of Electrica Engineering and Electronics Faculty of Technology Abu-Bekr BelkaM University AlgeriaTlemcen 13000

The current demand growth of new components capable of operating at high power, high frequency, high temperatures and convergence towards miniaturization has lead to the development of new fields of nanotechnology based on II-VI semiconductor Interest in nanostructure：s based on II-VI semiconductor narrow gap containing mercury （such as super lattices HgTe/CdTe） was due to their advantages over alloys with cadmium telluride Mercury （MCT： HgCdTe）. The ternary alloy is a semiconductor band-gap direct, in that work the main interest is about the ternary compound. The results obtained are very satisfactory, they are compared with experimental results, and are in good agreement. These results are very promising and open new perspectives for the realization of solar cells and applications in the field of sensors.

关键词： Monte Carlo simulation steady-state electron transport transient electron transport alloy scattering.

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Anatomical and Adaptation Features of <i>Pistacia atlantica</i>Desf. to Adverse Climate Conditions in Algeria

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American Journal of Plant Sciences 2017年第2期8卷 137-153页

作者： Mohamed Amara mohammed bouazza Mohannad G. Al-Saghir Bouchaib Belhadj University Centre Department of Natural Sciences and Life Ain Temouchent Algeria Laboratory of Ecology and Management of Natural Ecosystems Abou Bakr Belkaid University Tlemcen Algeria Laboratory of Ecology and Management of Natural Ecosystems Department of Ecology and Environment Abou Bakr Belkaid University Tlemcen Algeria Department of Environmental and Plant Biology Ohio University Zanesville Ohio USA

This work was conducted to assess the anatomical features of Pistacia atlantica Desf. under Mediterranean semi-arid climate conditions. In this study, phytoecological approach was used at different observation scales including the large ecological scale. 11 samples of P. atlantica species were randomly selected in order to study the anatomy of leaves and branches. The results show that leaves have palisade parenchyma occupying almost the entire mesophyll, measuring 100 to 170 μm. While in branches, the only pith occupies 38% followed by the xylem (24%), relative to the rest of the tissue (epidermis, periderm, collenchyma, pericyclic fiber, secretory duct and phloem). The current results suggest that P. atlantica species has xeromorphic anatomical characters, giving it great ecological plasticity in an arid environment. Moreover, this study shows that the human activities are causing local extinction of this rare species in Algeria.

关键词： Pistacia atlantica Xeromorphic Anatomy Adaptation Arid/Semi-Arid Algeria

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Study of Behavior Germination and Essays the Removing Tegumentary Inhibition of Seeds of Chamaerops humilis L. var. argentea Andre （Arecaceae）

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Journal of Life Sciences 2013年第5期7卷 501-506页

作者： Nadjat Medjati Okkacha Hasnaoui Nouria Hachemi Brahim Babali mohammed bouazza Department of Ecology and Environment Abou Bakr Belkaid University Tlemcen 13000 Algeria Department of Biology Dr Tahar Moulay University Sa~da 20000 Algeria Ecological and Natural Ecosystem Managements Laboratory University of Tlemcen Tlemcen 13000 Algeria

The regeneration conditions of Chamaerops humilis L. （Arecaceae）, has been threatened by a strong tegumentary inhibition of its seeds. In this study, the authors have analyzed the germination behavior of the species to plan subsequently for protection and sustainable use of this natural resource through synchronization and homogenization of germination. In this context and to optimize Chamaerops humilis seeds germination, to overcome and to remove the obstacle of tegumentary inhibition, the treatments by soaking in distilled water, manual, mechanical and chemical scarification （H2SO4）, have been applied to the seeds of Chamaerops humilis freshly harvested in the Beni Snous area （Tlemcen Mountain, Algeria）. The seeds germination without treatment （control） has been represented by a good germination capacity （72%） and a significantly longer duration of germination （46 days）. Soaking in distilled water does not seem to have a significant effect on the rate and duration of seeds germination compared to dry seeds （P 〉 0.05）. The manual scarification has clearly improved the germination capacity of these species （92%）, and a change wed has been seen in the germination duration （16 days）. However, mechanical scarification of seeds gave only low germination rate （42%）. Seeds treatment with sulfuric acid has been found to affect the rate of germination, but this effect is varied depending on the concentration of the acid. Overall, the germination percentage has changed from 77% to 92%. The optimal value of 92% corresponds to a concentration of 96%.

关键词： Chamaerops humilis L. Arecaceae tegumentary inhibition germination scarification.

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EECLP: AWireless Sensor Networks Energy Efficient Cross-Layer Protocol

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Computers, Materials & Continua 2024年第8期80卷 2611-2631页

作者： mohammed Kaddi mohammed Omari Moamen Alnatoor LDDI Laboratory University of AdrarAdrar01000Algeria Computer Science and Engineering Department School of EngineeringAmerican University of Ras Al KhaimahRas Al Khaimah72603United Arab Emirates

Recent advancements in wireless communications have allowed the birth of novel wireless sensor networks(WSN).A sensor network comprises several micro-sensors deployed randomly in an area of interest.A micro-sensor is provided with an energy resource to supply electricity to all of its ***,the disposed energy resource is limited and battery replacement is generally *** this restriction,the sensors must conserve energy to prolong their *** energy conservation strategies for WSNs have been presented in the literature,from the application to the physical *** of these solutions focus only on optimizing a single layer in terms of energy *** this research,a novel cross-layer technique for WSNs’effective energy usage is *** most energy consumption factors exist in the Medium Access Control(MAC)layer and network layer,our EECLP protocol(Energy Efficient Cross-Layer Protocol for Wireless Sensor Networks)integrates these two layers to satisfy energy efficiency *** gain access to the transmission channel,we implement a communication regime at the MAC layer based on CSMA/CA(Carrier Sense Multiple Access/Collision Avoidance)***,depending on the activity and a standby period,we employ the RTS/CTS(Request to Send/Clear to Send)method to prevent collisions and resolve hidden node concerns by utilizing the network allocation vector(NAV)to calculate the transmission *** a greedy strategy,we establish chains amongst cluster members to mitigate the issue of high energy consumption in routing *** objective function was utilized to determine the optimal cross-chain path based on the distances to the base station(BS)and residual energy(RE).The simulation,testing,and comparison of the proposed protocol to peer protocols have shown superior outcomes and a prolonged network *** the suggested protocol,the network lifetime increases by 10%compared to FAMACO(Fuzzy and Ant Col

关键词： WSN energy consumption MAC layer network layer EECLP energy-efficient lifespan

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Smartphone-Based Wi-Fi Analysis for Bus Passenger Counting

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Computers, Materials & Continua 2024年第4期79卷 875-907页

作者： mohammed Alatiyyah Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAl-Kharj16278Saudi Arabia

In the contemporary era of technological advancement,smartphones have become an indispensable part of individuals’daily lives,exerting a pervasive *** paper presents an innovative approach to passenger countingonbuses throughthe analysis ofWi-Fi signals emanating frompassengers’mobile *** study seeks to scrutinize the reliability of digital Wi-Fi environments in predicting bus occupancy levels,thereby addressing a crucial aspect of public *** proposed system comprises three crucial elements:Signal capture,data filtration,and the calculation and estimation of passenger *** pivotal findings reveal that the system demonstrates commendable accuracy in estimating passenger counts undermoderate-crowding conditions,with an average deviation of 20%from the ground truth and an accuracy rate ranging from 90%to 100%.This underscores its efficacy in scenarios characterized by moderate levels of ***,in densely crowded conditions,the system exhibits a tendency to overestimate passenger numbers,occasionally doubling the actual *** acknowledging the need for further research to enhance accuracy in crowded conditions,this study presents a pioneering avenue to address a significant concern in public *** implications of the findings are poised to contribute substantially to the enhancement of bus operations and service quality.

关键词： Public transportation digital environment passenger estimation signal capturing Wi-Fi

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Integrated photonic fractional convolution accelerator

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Photonics Research 2024年第8期12卷 1828-1839页

作者： KEVIN ZELAYA mohammed-ALI MIRI Department of Physics Queens College of the City University of New YorkQueensNew York 11367USA Physics Program The Graduate Center of the City University of New YorkNew YorkNew York 10016USA

An integrated photonic circuit architecture to perform a modified-convolution operation based on the discrete fractional Fourier transform(DFrFT) is introduced. This is accomplished by utilizing two nonuniformly coupled waveguide lattices with equally spaced eigenmode spectra, the lengths of which are chosen so that the DFrFT and its inverse operations are achieved. A programmable modulator array is interlaced so that the required fractional convolution operation is performed. Numerical simulations demonstrate that the proposed architecture can effectively perform smoothing and edge detection tasks even for noisy input signals, which is further verified by electromagnetic wave simulations. Notably, mild lattice defects do not jeopardize the architecture performance, showing its resilience to manufacturing errors.

关键词： fractional convolution utilizing

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