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Approaches for Delineating Landslide Hazard Areas Using Different Training Sites in an Advanced Artificial Neural Network Model

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Geo-Spatial Information Science 2010年第2期13卷 93-102页

作者： Biswajeet Pradhan Ahmed M. youssef Renuganth Varathrajoo Institute of Cartography Faculty of Forestry Hydro and Geosciences Dresden University of Technology Faculty of Engineering University Putra Malaysia Saudi Geological Survey Applied Geology Section Department of Geological Hazards and Engineering

The current paper presents landslide hazard analysis around the Cameron area, Malaysia, using advanced artificial neural networks with the help of Geographic Information System (GIS) and remote sensing techniques. Landslide locations were determined in the study area by interpretation of aerial photographs and from field investigations. Topographical and geological data as well as satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. Ten factors were selected for landslide hazard including: 1) factors related to topography as slope, aspect, and curvature; 2) factors related to geology as lithology and distance from lineament; 3) factors related to drainage as distance from drainage; and 4) factors extracted from TM satellite images as land cover and the vegetation index value. An advanced artificial neural network model has been used to analyze these factors in order to establish the landslide hazard map. The back-propagation training method has been used for the selection of the five different random training sites in order to calculate the factor's weight and then the landslide hazard indices were computed for each of the five hazard maps. Finally, the landslide hazard maps (five cases) were prepared using GIS tools. Results of the landslides hazard maps have been verified using landslide test locations that were not used during the training phase of the neural network. Our findings of verification results show an accuracy of 69%, 75%, 70%, 83% and 86% for training sites 1, 2, 3, 4 and 5 respectively. GIS data was used to efficiently analyze the large volume of data, and the artificial neural network proved to be an effective tool for landslide hazard analysis. The verification results showed sufficient agreement between the presumptive hazard map and the existing data on landslide areas.

关键词： artificial neural network landslide hazard GIS Malaysia

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Subnormal Serum Liver Enzyme Levels:A Review of Pathophysiology and Clinical Significance

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Journal of Clinical and Translational Hepatology 2024年第4期12卷 428-435页

作者： Elham M.youssef George Y.Wu Biochemistry Department National Research CenterCairoEgypt Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Subnormal levels of liver enzymes,below the lower limit of normal on local laboratory reports,can be useful *** instance,subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney *** alkaline phosphatase levels may indicate the presence of hypophosphatasia,Wilson's disease,deficiencies of divalent ions,or *** levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis,the use of certain medications,and in bone ***,subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic *** aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

关键词： Transaminases Vitamin B6 Celiac disease Renal insufficiency Hepatolenticular Degeneration Crohn disease Malnutrition Clofibrate Bone diseases Lead poisoning Anemia Hemolytic

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Breaking seed dormancy in Cupressus atlantica Gaussen,an endemicand threatened coniferous tree in Morocco

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Journal of Forestry Research 2012年第3期23卷 385-390页

作者： Sfairi youssef Ouahmane Lahcen Abbad Abdelaziz Direction Provinciale des Eaux et Forets et de la lutte contre laDésertification MarrakechMaroc Laboratoire de Biotechnologies Protection et Valorisation des Ressources Végétalesdépartement deBiologieEquipe de Phytochimie et Pharmacologie des Plantes Aromatiques et MédicinalesFacultédes Sciences SemlaliaUniversitéCadi AyyadMarrakechMaroc Centre Régional de Recherche Forestière Circuit de la PalmeraieMarrakechMaroc Laboratoire de Biotechnologies Protection et Valorisation desRessources Végétalesdépartement de BiologieEquipe de Phytochimieet Pharmacologie des Plantes Aromatiques et MédicinalesFacultédesSciences SemlaliaUniversitéCadi AyyadMarrakechMaroc

Cupressus atlantica Gaussen （Cupressaceae） is an endemic and endangered coniferous tree geographically restricted to the N＇Fis valley in South-Western Morocco. Like many forest species, C. atlantica exhibits dormancy which delays and reduces germination. To improve seed germination, different pre-treatments were conducted on C. atlantica seeds after storage for different periods （one, two and five years） including： scarification with sandy paper; soaking seeds in hot distilled water at 60℃ and 80℃ for 15 min and soaking seeds for 48 h in a gibberellic acid （GA3） at 1,000 and 2,000 mg·L-1. Results showed that scarification with sandy paper increased the germination rate of Atlas cypress by up to 67%, indicating that the species possess essentially an exogenous dormancy （physical dormancy） due to the hard seed coat （hardseededness）. Exogenous application of gibberellic acid （GA3） at 1,000 mg.L-1 was also effective in breaking seed dormancy and germination induction. These two treatments induced faster speed germination expressed by low number of days to first germination （8-10 days） and low values of mean germination times （MGT）. However, germination rate, under any treatment, is greatly dependent on the year of seed collection. Seeds collected in year 2004 gave the highest value, suggesting that even after five years of storage, the germination capacity of C. atlantica seeds could remain high. This observation is very interesting in the ex-situ conservation of such endemic and endangered species where the production of seeds is irregular over the years.

关键词： Cupressus atlantica endemic endangered breaking seed dormancy germination capacity hand scarification ex-situ conservation

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Do endemic species always have a low competitive ability? A test for two Mediterranean plant species under controlled conditions

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Journal of Plant Ecology 2012年第3期5卷 305-312页

作者： Eric Imbert Sami youssef David Carbonell Alex Baumel Institut des Sciences de l’Evolution CNRS 5554Universite Montpellier 2France Institut Mediterraneen d’Ecologie et de Paleoecologie UMR CNRS/IRD 6116Universite Aix MarseilleFrance

Aims Many observations concerning biological and ecological differentiation between narrow endemic and widespread congeneric plant species suggest that narrow endemic species are constrained to colonize marginal habitats because of a low tolerance to *** this topic being an important issue both for understanding evolutionary processes leading to endemism and for conservation purposes,few studies have been performed to compare competitive abilities between endemic and widespread ***,we present two independent experiments performed under controlled conditions using two different pairs of endemic and widespread congeneric species:Centaurea corymbosa/Centaurea maculosa and Arenaria provincialis/Arenaria serpyllifolia,both endemic species occurring in rocky calcareous *** Mature seeds of *** and *** were sown in pots containing ramets of the common grass,Brachypodium *** were sorted in three treatments according to grass cover(low,intermediate and high).A control treatment(without competition)was also ***,seedling survival and rosette growth were *** the comparisons between *** and ***,seeds from natural populations were first sown without a *** week after germination,healthy seedlings were transplanted in pots without Brachypodium seedling(control)or containing two Brachypodium seedlings(low competition)or four seedlings(high competition).We checked the number of capsules per individual,and we harvested the biomass after capsule *** Findings Despite differences in the protocol design,results are congruent,and in both cases,endemic species are highly affected by the presence of a competitor,as are the widespread species,although we did not detect any differences between species for response to *** results are discussed in relation to processes leading to endemism,suggesting that the specialist model is more likely for both the

关键词： endemism conservation biology Mediterranean area competitive response

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Electrochemical behavior and analytical detection of Imidacloprid insecticide on a BDD electrode using square-wave voltammetric method

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Chinese Chemical Letters 2016年第5期27卷 666-672页

作者： Mabrouk Ben Brahim Hafedh Belhadj Ammar Ridha Abdelhedi youssef Samet Electrochemistry and Environmental Laboratory Department of Materials Engineering National Engineering School of Sfax University of Sfax B.P. I 1733038 Sfax Tunisia

A sensitive square-wave voltammetric method for the determination of lmidacloprid （IMD） was developed using electrochemically pretreated boron-doped diamond （BDD） electrode. Aqueous solutions were prepared with Confidor 200 SL as the commercial formulation of IMD. Sodium sulfate （Na2SO4） was used as supporting electrolyte. The influence of operating parameters, such as the pH of the medium, frequency, pulse amplitude, scan increment and the concentration of IMD was investigated. An irreversible cathodic peak, corresponding to the reduction oflMD is observed at 1.21 V （vs. SCE） and the electrode reaction was controlled by adsorption. Under optimized conditions, the square-wave reduction peak current was linear over the concentration range of （30-200 μmol L 1） with a detection and quantification limits of 8.60 μmol L 1 and 28.67 μmol L 1, respectively. The results were compared with spectrophotometry and HPLC methods under some conditions and found to be in good agreement. To investigate applicability to real samples, the proposed method was applied to the determination of IMD in plum juice.

关键词： Imidacloprid Square-wave volammetry Boron-doped diamond electrode Electrochemical detection

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Structural, electronic, and optical studies of chalcogenides stannite Cu2CdSnX4（X=S, Se, and Te）: insights from the DFT study

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Optoelectronics Letters 2025年第2期 69-76页

作者： Jamal GUERROUM Mohamed AL-HATTAB Lhoucine MOUDOU Khalid RAHMANI youssef LACHTIOUI Omar BAJJOU Laboratory of Engineering in Chemistry and Physics of Matter Faculty of Sciences and Technics Sultan Moulay Slimane University Ecole Normale Supérieure Mohammed V University in Rabat College of Graduate Studies University of South Africa

In this paper,we have calculated the structural,electronic,and optical properties of chalcogenide stannite Cu2CdSnX4（X=S,Se,Te） *** calculations are based on the density functional theory （DFT） method and are performed using the Cambridge sequential total energy package （CASTEP） code included in the Biovia Material Studio 20 *** optical properties have been studied in a domain that extends energetically from 10 meV to 40 *** results show that Cu2CdSnX4（X=S,Se,Te） stannite exhibits absorption in the visible region,the refractive index decreases with increasing energy,and the refractive index values are n=3.2,3.73 and 3.75 for Cu2CdSnS4,Cu2CdSnSe4and Cu2CdSnTe4,*** show also high conductivity,which implies that this material is promising for solar *** results argue in favor of the use of these materials in various potential *** density of state,band structures,and structural properties of Cu2CdSnX4（X=S,Se,and Te） stannite are also studied in this work.

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Microwave Transmission Through One-Dimensional Hybrid Quasi-Regular （Fibonacci and Thue-Morse）/ Periodic Structures

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Photonic Sensors 2013年第3期3卷 246-255页

作者： youssef TRABELSI Naim BENALI Yassine BOUAZZI Mounir KANZARI LPMS Laboratory of Photovoltaic and Semi-conductor Materials ENIT EL Manar University ENIT-BP 37 Belvedere 1002 Tunis Tunisia

The transmission properties of hybrid quasi-periodic photonic systems （HQPS） made by the combination of one-dimensional periodic photonic crystals （PPCs） and quasi-periodic photonic crystals （QPCs） were theoretically studied. The hybrid quasi-periodic photonic lattice based on the hetero-structures was built from the Fibonacci and Thue-Morse sequences. We addressed the microwave properties of waves through the one-dimensional symmetric Fibonacci, and Thue-Morse system i.e., a quasi-periodic structure was made up of two different dielectric materials （Rogers and air）, in the quarter wavelength condition. It shows that controlling the Fibonacci parameters permits to obtain selective optical filters with the narrow passband and polychromatic stop band filters with varied properties which can be controlled as desired. From the results, we presented the self-similar features of the spectra, and we also presented the fractal process through a return map of the transmission coefficients. We extracted powerfully the band gaps of hybrid quasi-periodic multilayered structures, called ＂pseudo band gaps＂, often containing resonant states, which could be considered as a manifestation of numerous defects distributed along the structure. The results of transmittance spectra showed that the cutoff frequency could be manipulated through the thicknesses of the defects and the type of dielectric layers of the system. Taken together, the above two properties provide favorable conditions for the design of an all-microwave intermediate reflector.

关键词： Photonic crystals aperiodic sequence quasi-periodic photonic band gap Thue-Morse class quasi-periodic Fibonacci class quasi-periodic microwave reflector

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Fabrication,characterization,and electrical conductivity properties of Pr_6O_(11) nanoparticles

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Journal of Rare Earths 2013年第7期31卷 701-708页

作者： Bahaa M.Abu-Zied youssef A.Mohamed Abdullah M.Asiri Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt Center of Excellence for Advanced Materials Research(CEAMR) King Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

PrrOll nanoparticles were obtained by subsequent thermal decomposition of the as-prepared precipitate formed under ambient temperature and pressure using NaOH as precipitant. The calcination process was affected, for 1 h in static air atmosphere, at 400-700 ℃ temperature range. The different samples were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEM）, field emission scanning electron microscopy （FE-SEM）, thermogravimetric analysis （TGA）, in situ electrical conductivity, and N2 adsorption/desorption. The obtained results demonstrated that nano-crystalline Pr6O11, with crystallites size of 6-12 nm, started to form at 500 ℃. Such value increased to 20-33 nm for the sample calcined at 700℃. The as-synthesized PrrOll nanoparticles presented high electrical conductivity due to electron hopping between Pr（III）-Pr（IV） pairs.

关键词： nanocrystalline praseodymium oxide Pr6O11 nano structured materials electrical conductivity rare earths

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Active Power Filter ——Didactic System of Compensation of Harmonics and Reactive Power

Active Power Filter ——Didactic System of Compensation of H...

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作者： Rafi youssef（约瑟夫）中南大学

学位级别：硕士

像任何电力发电机一样,电力网络通过他们终端机上的电压调节器给仪器使用者提供能量。很明显,电能质量取决于在发送点上的电压。这一个电压通常要承受许多干扰,这些干扰主要来自于二个截然不同的来源: 由通道所引起的电压干扰,在供电... 详细信息

像任何电力发电机一样,电力网络通过他们终端机上的电压调节器给仪器使用者提供能量。很明显,电能质量取决于在发送点上的电压。这一个电压通常要承受许多干扰,这些干扰主要来自于二个截然不同的来源: 由通道所引起的电压干扰,在供电网络中,干扰电流如谐波,不平衡和无功电流。由谐波和不平衡电压以及电压突降等引起的干扰电压。电网中,由非线性和不平衡负载引起的不平衡和谐波电流将造成谐波和不平衡电压。这些电压扰动和电压降将严重影响用户端的电能质量。如今,有源滤波器,如并联、串联和串并联组合有源滤波器,被广泛研究,以保持电压和电流的平衡。本文主要设计了有源滤波器。采用并联型有源滤波器使非线性负载的电网功率因数接近1。有源滤波器补偿负载消耗的无功和谐波,使电网仅传输有功功率。滤波器由一个电容、一个电感和四个电能开关组成。电容为平衡能量的能量储存元件。电感是减少电流变化的续流元件。电能开关是控制能流方向的元件。只要电容电压比系统电压高,则电能开关就能控制能流方向。开关除了能控制系统电流为无谐波的正弦波,还能使系统的电流与电压同相。通过比较电容电压和参考电压,生成参考电压幅值定义的命令,使电容电压保持恒定。在硕士学位毕业论文报告的提纲中,提出了一个谐波学和无功功率的补偿教导的系统。自动化所控制工程实验室已经做出了原型(在中南大学) 在实验室的技术助理和罗安教授的指导下,采用的方法使教导系统在电子工程学(在系统的测试结构里面)中的使用同在物理学的TP中的应用一样成为可能。有源补偿器基于一爪“教学的”逆变器,产品的特性(电流-电压)使电子工程的视在功率使用负荷成为可能(测试装置限制在3千瓦),给网络LT企业供应400V的电压。为了达到教学目的,我们选择采用顺序图表进行类推。因此使学生容易地分析出控制回路的结构并用示波器检测出信号。正常工作状态允许运行在无功功率或谐波的整流PWM中,也允许运行在整流PWM中,吸收正弦波。补偿器可能连接任何平衡三相非线性负荷。在这篇论文中包含: PWM逆变器补偿控制的研究;功率元件和控制回路的参数确定;检测电路功能和结构的研究。

关键词：教学的模拟有源滤波器谐波补偿控制系统

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Optimal stopping in predictable setting

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Probability, Uncertainty and Quantitative Risk 2023年第4期8卷 485-498页

作者： Siham Bouhadou Astrid Hilbert youssef Ouknine Department of Mathematics Faculty of Sciences SemlaliaCadi Ayyad UniversityBd.Prince My AbdellahB.P.239040000 MarrakechMorocco Department of Mathematics Linnaeus UniversityB2051Hus BVäxjöSweden Mohammed VI Polytechnic University Hay Moulay Rachid Ben Guerir43150Morocco

In this study,we delve into the optimal stopping problem by examining the p(ϕ(τ),τ∈T_(0)^(p))case in which the reward is given by a family of nonnegative random variables indexed by predictable stopping *** aim to elucidate various properties of the value function family within this *** prove the existence of an optimal predictable stopping time,subject to specific assumptions regarding the reward functionϕ.

关键词： Optimal stopping Supermartingale Predictable stopping time Admissible family Reward

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