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Application of advanced reproductive biotechnologies for buffalo improvement with focusing on Egyptian buffaloes

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Asian pacific Journal of Reproduction 2018年第5期7卷 193-205页

作者： kamel m.E.mohammed Animal Reproduction Research Institute HaramGizaEgypt

many countries in the world consider the buffalo as a priority animal for the future, since it plays a pivotal role in human food sustainability. Even though Food and Agriculture Organization has termed the buffalo as an important undervalued asset, this species has yet to drive the same attention as cattle. Egypt has a wealth of buffaloes dispersed in small herds all over the country, so the efforts that have been made to improve their genetic background show little return. Contrarily, other countries concerned with buffalo improvement have already used a data recording system in buffalo herds, allowing to achieve a much faster improvement progress. This review intends to survey the existing information on the application of assisted reproduction techniques to improve buffalo productivity. The strength points that may help to improve buffalo production are identified, and the obstacles hindering the genetic improvement of Egyptian buffalo are characterized. Therefore, this work will gather information related to buffalo and compile it for an audience of researchers and specialists to enforce international collaboration for the development of buffalo production. Also, it will open the way for people interested in developing a future vision for buffalo potential, which will be helpful to close or minimize the biological gaps of buffaloes' researches.

关键词： Buffaloes Egypt Artificial insemination Embryo transfer Estrus synchronization Frozen semen Embryo freezing

A Hybrid Virtual Cloud Learning model during the COVID-19 Pandemic

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Computers, materials & Continua 2021年第3期66卷 2671-2689页

作者： Shaymaa E.Sorour Tamer m.kamel Hanan E.Abdelkader Department of Educaion Technology(Computer Teacher Preparation) Kafrelsheikh University33516Egypt Department of Educaion Technology Kafrelsheikh University33516Egypt Department of Computer Teacher Preparation Mansoura University35516Egypt

The COVID-19 pandemic has affected the educational systems worldwide,leading to the near-total closures of schools,universities,and *** need to adapt to changes to face this crisis without negatively affecting students’***,the purpose of this study is to identify and help solve to critical challenges and factors that influence the e-learning system for Computer maintenance courses during the COVID-19 *** paper examines the effect of a hybrid modeling approach that uses Cloud Computing Services(CCS)and Virtual Reality(VR)in a Virtual Cloud Learning Environment(VCLE)*** VCLE system provides students with various utilities and educational services such as presentation slides/text,data sharing,assignments,quizzes/tests,and *** addition,learning through VR enables the students to simulate physical presence,and they respond well to VR environments that are closer to reality as they feel that they are an integral part of the ***,the research presents a rubric assessment that the students can use to reflect on the skills they used during the *** research findings offer useful suggestions for enabling students to become acquainted with the proposed system’s usage,especially during theCOVID-19 pandemic,and for improving student achievementmore than the traditional methods of learning.

关键词： Virtual cloud learning environment virtual reality environment rubric assessment COVID-19 critical challenges

Column leaching of lanthanides from Abu Tartur phosphate ore with kinetic study

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Journal of Rare Earths 2010年第4期28卷 576-580页

作者： A.T. Kandil m.m. Aly E.m. moussa A.m. kamel m.m. Gouda m.N. Kouraim Chemistry Department Faculty of Science Helwan University Nuclear materials Authority P.O. Box 530 El Maadi Cairo Egypt

The dynamic leaching of lanthanides from a west desert phosphate ore, Egypt (Abu Tartur) by hydrochloric acid, nitric acid and sulfuric acid solutions was investigated in this study as a function of acid concentration, flow rate and the presence of some additives such as boric acid. Also the kinetics of leaching of lanthanides was investigated as a function of temperature. It was found that the leaching process could be described by a shrinking-core model, with activation energy about 5.9, 13.8 and 21.9 kJ/...

关键词： column leaching lanthanides Abu Tartur hydrochloric acid nitric acid sulfuric acid kinetics rare earths

Biochar reduces colloidal phosphorus in leachate by regulating phoD- and phoC-harboring microbial communities during drying/rewetting cycles

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Biochar 2023年第1期5卷 1014-1028页

作者： Xiaochun Wang Hongnuo Ge Yunying Fang Chunlong Liu kamel m.Eltohamy Zekai Wang Xinqiang Liang Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of ministry of Water Resources College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China College of Agriculture and Biotechnology Zhejiang UniversityHangzhou 310058China Australian Rivers Institute School of Environment and ScienceGriffith UniversityNathan CampusBrisbaneQLD 4111Australia Key Laboratory of mollisols Agroecology Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081China

Drying and rewetting(DRW)events cause the release of colloidal phosphorus(P_(coll),1-1000 nm)in leachate,and biochar is considered an effective inhibitor;however,the microbial mechanism remains *** this study,three successive DRW cycles were performed on the soil columns to assess the effect of biochar addition on P_(coll) content and its possible associates,including phosphatase-producing microbial populations(phoD- and phoC-harboring microbial communities)and alkaline/acid phosphatase(ALP/ACP)*** showed that the biochar addition significantly decreased the P_(coll) by 15.5-32.1%during three DRW *** structural equation model(SEm)confirmed that biochar addition increased phoD- and phoC-harboring microbial communities and ALP/ACP activities,which reduces the release of P_(coll) into *** addition,the manure biochar was more effective than the straw biochar in promoting competition and cooperation in the co-occurrence network(2-5%nodes increased on average),and the key taxa Proteobacteria and Cyanobacteria were identified as the dominant species of potential ALP/ACP activities and P_(coll) *** findings provide a novel understanding of biochar reducing P_(coll) loss from the phosphatase perspective by regulating the phoD-and phoC-harboring communities during DRW events.

关键词： Drying and rewetting events Alkaline/acid phosphatase microbial mechanism Proteobacteria Cyanobacteria

Dynamic Characteristics of Inflated Torus Using Finite Element Analysis

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Computer Aided Drafting,Design and manufacturing 2010年第1期20卷 15-20页

作者： kamel m A School of Astronautics Beijing University of Aeronautics and Astronautics

In recent years, inflatable structures have been a subject of interest for space applications such as communication antenna, solar thermal propulsion and entry/landing systems. The inflatable structures characterized by high strength-to-mass ratios, minimal stowage volume, which makes them suitable for cost-effective large space structures. A typical example for the inflatable structure is the inflated torus which often used in order to provide structure support. In this study, our main focus is to understand the dynamic characteristics of an inflated torus in order to formulate an accurate mathematical model suitable for active vibration control applications. A commercial finite element package, ANSYS, is used to model the inflated torus. To verify the model the obtained frequencies and mode shapes are compared with the published results, which are derived using analytical approach, the verification shows a good agreement between the FEm and the analytical results. Based on the verified model, parametric study was investigated; the material thickness increase causes the natural frequencies decrease, while the increase of the inflation pressure simply results in stiffening the ring, which means that the natural frequency increased. The FEm analysis gives an easy and fast way for the vibration analysis of the structures compared with the complicated analytical solutions.

关键词： dynamic characteristics inflatable torus finite element modelling (FEm) modal analysis

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微粒群优化算法研究现状及其进展

计算机工程 2004年第21期30卷 3-4,9页

作者：杨燕靳蕃 kamel m 西南交通大学计算机与通信工程学院成都610031 UniversityofWaterloo

对进化计算中引起广泛兴趣的微粒群优化(PSO)算法的研究现状进行了考察,介绍了一些最新研究进展,包括:杂交PSO、基于邻域算子的PSO和基于不同搜索方向的PSO,并简要介绍了PSO在求解复杂优化问题如多目标优化和带约束优化中的优势。最后... 详细信息

对进化计算中引起广泛兴趣的微粒群优化(PSO)算法的研究现状进行了考察,介绍了一些最新研究进展,包括:杂交PSO、基于邻域算子的PSO和基于不同搜索方向的PSO,并简要介绍了PSO在求解复杂优化问题如多目标优化和带约束优化中的优势。最后给出了一些应用实例,讨论了将来可能的研究内容。

关键词：微粒群优化进化计算群集智能 PSO 蚁群算法

Design and Testing of Three Earthing Systems for micro-Grid Protection during the Islanding mode

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Smart Grid and Renewable Energy 2010年第3期1卷 132-142页

作者： Rashad m. kamel Aymen Chaouachi Ken Nagasaka 不详

This paper presents and tests three earthing systems (TT, TN and IT) for micro-Grid (mG) protection against various fault types when the mG transferred to the islanding mode. The main contribution of this work is including the models of all micro sources which interfaced to the mG by power electronic inverters. Inverters in turns are provided with current limiters and this also included with the inverter models to exactly simulate the real situation in the mG during fault times. Results proved that the most suitable earthing system for mG protection during the islanding mode is the TN earthing system. That system leads to a suitable amount of fault current sufficient to activate over current pro-tection relays. With using TN earthing system, touch voltages at the faulted bus and all other consumer’s buses are less than the safety limited values during islanding mode. For the two others earthing systems (TT and IT), fault currents are small and nearly equal to the over load currents which make over current protection relay can not differentiate between fault currents and overload currents. All models of micro sources, earthing systems, inverters and control schemes are built using matlab?/Simulink? environment.

关键词： micro Grid Protection Earthing Systems Fault Current Touch Voltage micro Sources and Inverters

Detailed Analysis of micro-Grid Stability during Islanding mode under Different Load Conditions

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Engineering（科研） 2011年第5期3卷 508-516页

作者： Rashad m. kamel A. Chaouachi Ken Nagasaka 不详

Today, several types of DGs are connected together and formed a small power system called micro-grid (mG). mG is connected to the primary distribution network and usually operates in normal connecting mode. When a severe fault occurs in the primary distribution network, then the mG will transfer to islanding mode. In this paper a complete model is developed to simulate the dynamic performance of the mG during and subsequent to islanding process. The model contains of a solid oxide fuel cell (SOFC), a single shaft micro turbine, a flywheel, two photovoltaic panels and a wind generator system. All these micro sources are con-nected to the mG through inverters except the wind generation system. The inverters are modeled with two control strategies. The first strategy is PQ control which the inverter will inject a certain active and reactive powers. This type of inverter is used to interface micro turbine, fuel cell and photovoltaic panels to the mG. The second strategy is Vf control. This model is used to interface flywheel will act as the reference bus (slack bus) for the mG when islanding occurs. Two cases are studied: the first case discusses the effect of islanding process on frequency, voltage and active power of all micro sources when the mG imports active and reactive power from the primary distribution network. The second studied case, also, shows the effect of islanding on the previous quantities particularly when the mG exports active and reactive power to the pri-mary distribution network. Results showed that the existence of storage device (flywheel) with appropriate control of its inverter can keep the frequency of the mG and the voltages of all buses within their limited levels. The developed model is built in matlab? Simulink? environment.

关键词： mG Dynamic Performance Islanding Inverter and Distributed Generators

Drying Kinetics and Energy Consumption in Vacuum Drying Process with microwave and Radiant Heating

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Chinese Journal of Chemical Engineering 2004年第6期12卷 809-813页

作者： m.kamel J.I.Lombrana C.de Elvira R.Rodríguez Department of Chemical Engineering Facultad de Ciencias Universidad del Pais Vasco. Apdo. 644 48080 Bilbao SpainDepartment of Chemical Engineering Facultad de Ciencias Universidad del Pais Vasco. Apdo. 644 48080 Bilbao SpainInstituto del Frio (CSIC) Ciudad Universitaria. 28040 Madrid SpainDepartment of Chemical Engineering Facultad de Ciencias Universidad del Pais Vasco. Apdo. 644 48080 Bilbao Spain

The general objective of this work is to analyze energy input in a vacuum process with the incorporation of microwave heating. Thus, necessary criteria for designing an efficient freeze-drying operation are considered through the analysis of strategies based on the combination of different intensities of radiant and microwave *** other aim of this research topic is to study the kinetics of drying in relation to mass transfer *** freeze-drying strategies using both heating systems were used. Consequently, energy input could be related to diffusivity coefficients, temperature and pressure profiles during dehydration of the product and analyzed in comparison to a conventional freeze-drying process.

关键词： vacuum microwave drying diffusivity constant energy