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Optimized Numerical Model Based Assessment of Wave Power Potential of Marmara Sea

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Journal of Ocean University of China 2019年第2期18卷 293-304页

作者： abdOLLAHZADEHMORADI Yasin OZGER Mehmet ALTUNKAYNAK abdüsselam Hydraulics Division Department of Civil EngineeringIstanbul Technical University

Marmara Sea, located between Black Sea and Aegean Sea, is an important sea for ocean engineering activities. In this study, wave power potential of Marmara Sea was investigated using the third generation spectral wind-wave model MIKE 21 SW with unstructured mesh. Wind data was obtained from ECMWF ERA-Interim re-analyses wind dataset at 10 m with a spatial resolution of 0.1? for the period of 1994 to 2014. The numerical model was calibrated with measured wave data from a buoy station located in Marmara Sea. Mesh optimization was also performed to obtain the most suitable mesh structure for the study area. This study is the first that dealt with the determination of wave energy potential of Marmara Sea. The numerical model results are presented in terms of monthly, seasonal and annual average of wave power flux(k W m^(-1)). The maximum wave power flux is 1.13 kW m^(-1) and occurs in November. The overall annual mean wave power flux during 1994–2014 is found to be 0.27 kW m^(-1) in the offshore regions.

关键词： Marmara Sea MIKE 21 SW wave power potential ECMWF buoy wave data

Entropy Generation for Flow and Heat Transfer of Sisko-Fluid Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第1期62卷 37-59页

作者： Mohamed abd El-Aziz A.M.Aly Department of Mathematics Faculty of ScienceKing Khalid UniversityAbha61411Saudi Arabia Department of Mathematics Faculty of ScienceHelwan UniversityHelwan-Cairo11795Egypt Department of Mathematics Faculty of ScienceSouth Valley UniversityQena83523Egypt

In the present study,the effects of the magnetic field on the entropy generation during fluid flow and heat transfer of a Sisko-fluid over an exponentially stretching surface are *** similarity transformations are used to transfer the governing partial differential equations into a set of nonlinear-coupled ordinary differential ***-Kutta-Fehlberg method is used to solve the governing *** effects of magnetic field parameter,local slip parameterλ,generalized Biot numberγ,Sisko fluid material parameter,Eckert number Ec,Prandtl number Pr and Brinkman number Br at two values of power law index on the velocity,temperature,local entropy generation number N_(G) and Bejan number Be are ***,the tabular forms for local skin friction coefficient and local Nusselt number under the effects of the physical parameters are *** current results are helpful in checking the entropy generation for *** is found that,an extra magnetic field parameter makes higher Lorentz force that suppresses the *** shear thinning fluids(n<1),the temperature dominates and the velocity *** entropy generation number is more for larger generalized Biot number,magnetic field parameter and Brinkman *** local skin friction coefficient increases as magnetic field parameter and material parameter are increase and it decreases as local slip parameter *** local Nusselt number decreases as magnetic field parameter,local slip parameter and Eckert number are increase,while it increases as material parameter,generalized Biot number and Prandtl number are increase.

关键词： Boundary layer entropy generation exponentially stretching surface magnetic field sisko-fluid

Measurements of natural radionuclides in soil samples from Upper Egypt

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Nuclear Science and Techniques 2008年第5期19卷 302-307页

作者： Shaban Ramadan Mohamed HARB Khaled SALAHEL DIN abd Elbaset ABBADY Mohamed abd Elleh ALI Rolf MICHEL Physics Department Faculty of ScienceSouth Valley University Center for Radiation Protection and Radioecology Hanover University (ZSR)

This paper presents the results of natural radioactivity measured for the soil of Qena using gamma-ray spectrometry at ZSR,Hanover University,*** samples of radioactive concentrations of ^(238)U-series (^(234)Th, ^(214)pb,and^(214)Bi),^(232)Th-series (^(228)Ac,^(212)pb,and ^(208)T1) and ^(40)K were *** objectives were set:(1) activity levels by surface soil sampling at 0～30 cm depth,(2) dose rates of gamma radiation,radium equivalent,index hazard, and effective dose,and (3) ambient dose rates.

关键词：土壤环境放射能 γ光谱测定法辐射暴露环境剂量

Multiple Major Thrombo-Embolic Events, including Stroke, in a Patient with Combined Congenital Anti-Thrombin III Deficiency and MTHFR Homozygous Mutation

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World Journal of Cardiovascular Diseases 2017年第3期7卷 71-78页

作者： Islam I. zaid Nora I. Abbas Ehab Shaker Foad abd-Allah Departement of Neurology Faculty of Medicine Cairo University Cairo Egypt Departement of Critical Care Medicine Faculty of Medicine Cairo University Cairo Egypt

We report a case of a young male patient suffering from congenital Anti-Thrombin III (AT III) deficiency, presented with four major thrombotic events. These events were acute coronary syndrome (Non-ST elevation myocardial infarction), cerebral infarction, peripheral acute upper limb (UL) ischemia and bilateral extensive deep venous thrombosis. The latter two developed despite that the patient was receiving full anticoagulation therapy. His International normalized ratio (INR) was 2.5. Eventually, the patient developed pulmonary embolism and died. He had a prominent family history of thrombotic events. Screening for AT III deficiency in young patients with thrombotic event (thrombophilia) is essential especially those having family history of the latter. This is justified as thrombotic events may occur in up to 80% of these patients. Our patient with 4 major thrombotic events ending in fatality in less than 1 month deserves the nomenclature.

关键词： Thrombophilia Thrombosis Congenital AT III Deficiency Stroke Acute Coronary Syndrome Deep Venous Thrombosis Acute Limb Ischemia

Spatio-temporal variation of zooplankton community structure in tropical urban waterbodies along trophic and urban gradients

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Ecological Processes 2019年第1期8卷 539-550页

作者： Siti Balqis abd.Razak Zati Sharip Lake Research Unit Water Quality and Environment Research CentreNational Hydraulic Research Institute of MalaysiaMinistry of WaterLand and Natural ResourcesLot 5377Jalan Putra Permai43300 Seri KembanganSelangorMalaysia

The ecological impacts of urbanization and eutrophication on zooplankton communities in urban waterbodies have recently gained wide *** findings vary across species and urban *** the development of such changes affects the variation of biotic assemblages has only been explored to a limited extent in tropical urban *** and temporal variations of zooplankton community structure in 11 urban waterbodies in the Klang Valley,Malaysia were investigated along trophic and urbanization *** and water quality samples were collected three times,between May and November 2017,from two different locations in each *** three main zooplankton groups(rotifera,copepoda,and cladocera)were recorded from the study areas throughout the sampling *** zooplankton community structure,particularly with regard to rotifers and cladocerans,varied between lakes and *** diversity does not vary with lake size or distance from the city center but does vary with shoreline development index and urbanization *** zooplankton populations were dominated by rotifers,mainly Brachionus angularis at all study sites during the study period followed by copepods and *** total density of zooplankton was significantly highest(p<0.05)in the hypereutrophic lakes and during the dry *** diversity and rotifer species richness were negatively correlated with total phosphorus(TP).Diversity increased with urbanization and shoreline development,with rotifers as a potential bioindicator of trophic state in urban tropical lakes,due to their close relationship with TP.

关键词： Eutrophication Rotifer Tropical ponds Urban waterbodies Zooplankton diversity

Fair subcarrier-power allocation scheme for multiuser multicarrier systems

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Journal of Central South University 2015年第8期22卷 3033-3041页

作者： Mohammed abd-Elnaby Germien G.Sedhom Nagy W.Messiha Xu Zhu Fathi E.abd El-Samie Faculty of Electronic Engineering Menoufia University Deptartment of Electrical Engineering and Electronics University of Liverpool

The main objective of multiuser orthogonal frequency division multiple access(MU-OFDM) is to maximize the total system capacity in wireless communication systems. Thus, the problem in MU-OFDM system is the adaptive allocation of the resources(subcarriers, bits and power) to different users subject to several restrictions to maximize the total system capacity. In this work, a proposed subcarrier allocation algorithm was presented to assign the subcarriers with highest channel gain to the users. After the subcarrier allocation, subcarrier gain-based power allocation(SGPA) was employed for power and bit loading. The simulation results show that the proposed subcarrier-power allocation scheme can achieve high total system capacity and good fairness in allocating the resources to the users with slightly high computational complexity compared to the existing subcarrier allocation algorithms.

关键词： multiuser orthogonal frequency division multiple access (MU-OFDM) subcarrier-allocation power allocation fairness capacity

MHD Boundary Layer Flow of a Power-Law Nanofluid Containing Gyrotactic Microorganisms Over an Exponentially Stretching Surface

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Computers, Materials & Continua 2020年第2期62卷 525-549页

This study focusses on the numerical investigations of boundary layer flow for magnetohydrodynamic(MHD)and a power-law nanofluid containing gyrotactic microorganisms on an exponentially stretching surface with zero nanoparticle mass flux and convective *** nonlinear system of the governing equations is transformed and solved by Runge-Kutta-Fehlberg *** impacts of the transverse magnetic field,bioconvection parameters,Lewis number,nanofluid parameters,Prandtl number and power-law index on the velocity,temperature,nanoparticle volume fraction,density of motile microorganism profiles is *** addition,the impacts of these parameters on local skin-friction coefficient,local Nusselt,local Sherwood numbers and local density number of the motile microorganisms are *** results reveal that the power law index is considered an important factor in this *** to neglecting the buoyancy force term,the bioconvection and nanofluid parameters have slight effects on the velocity *** resultant Lorentz force,from increasing the magnetic field parameter,try to decrease the velocity profiles and increase the rescaled density of motile microorganisms,temperature and nanoparticle volume fraction ***,an augmentation of power-law index drops the reduced local skin-friction and reduced Sherwood number,while it increases reduced Nusselt number and reduced local density number of motile microorganisms.

关键词： Bioconvection gyrotactic microorganisms magnetohydrodynamic nanofluid boundary layer power-law

Inundative field releases and evaluation of three predators for Bemisia tabaci （Hemiptera： Aleyrodidae） management in three vegetable crops

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Insect Science 2011年第2期18卷 195-202页

作者： Alvin M. Simmons Shaaban abd-Rabou USDA ARS U.S. Vegetable Laboratory Charleston South Carolina ARC PPRI Dokki Giza Egypt

The sweetpotato whitefly, Bemisia tabaci （Gennadius）（Hemiptera： Aleyrodidae）, is a global pest on numerous crops, including vegetables. Weekly inundative releases of a coccinellid predator （Coccinella undecimpunctata L. [Coleoptera： Coccinellidae]）, a common green lacewing predator （Chrysoperla carnea Stephen [Neuroptera： Chrysopidae]）, and a mirid predator （Macrolophus caliginosus [Wagner] [Hemiptera： Miridae]） were independently made in three vegetable crops （cabbage [Brassica oleracea var. capitata L.], cucumber [Cucumis sativus L.], and squash [Cucurbita pepo L.]） for the management of the sweetpotato whitefly. Approximately 1 million to 2.5 million larvae or nymphs of each predator were released in the vegetable crops during 20 weeks. Whitefly populations were reduced by ≈ 25%-45% during most of the season in each crop where each predator was released. The effect of each predator was similar on whitefly population reduction. Late in the season （October） when whitefly populations were low, generally no benefit was obtained from releasing the predators. Numbers of predators recovered during sampling in all crops were greatest for C. carnea, but this corresponded with the fact that more individuals of this predator were released than any other predator in the experiment. These results help define the utility of these natural enemies for managing B. tabaci in vegetable crops.

关键词： Bemisia tabaci Chrysoperla carnea Coccinella undecimpunctata Macrolophus caliginosus inundative release sweetpotato whitefly

Agrobacterium-Mediated Transformation of Rice: Constraints and Possible Solutions

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Rice science 2019年第3期26卷 133-146页

作者： Sulaiman MOHAMMED Azman abd SAMAD zaidah RAHMAT Department of Biotechnology and Medical Engineering Faculty of Biosciences and Medical Engineering Universiti Teknologi Malaysia Department of Biological Sciences Faculty of Science Gombe State University

Genetic transformation of rice(Oryza sativa L.) by introducing beneficial traits is now a central research instrument in plant physiology and a practical tool for plant improvement. Many approaches are verified for stable introduction of foreign genes into the plant genome. The review examined the different constraints that limit the success of rice genetic transformation via Agrobacterium-mediated approach and suggested possible solutions. Explant identification, gene transfer technique and construct to tailor the integration, transgene expression without collateral to genetic damage and transformant selection are among the technical challenges affecting the rice transformation. Despite the contests, Agrobacteriummediated transformation system has been a better option for producing transgenic rice varieties because of its exact T-DNA processing and simple integration of low copy-number transgene. This information is necessary for improving the transformation system for recalcitrant rice varieties.

关键词： rice Agrobacterium-mediated transformation tissue culture gene transfer T-DNA integration