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Treatment of Prostatorectal Fistula by Transanorectal Route: About an Observation

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Open Journal of Urology 2024年第4期14卷 262-266页

作者： mohamed mahmoud Beya Ahmed Salem Terouzi Y. Tfeil Diagana Mouhamadou Urology Department Cheikh Zayed Hospital Nouakchott Mauritania

This is a 54-year-old patient admitted for the management of urinary leakage through the anus that had been occurring for a month, in whom the diagnosis of a prostatorectal fistula was made. The fistula was successful... 详细信息

关键词： Fistula Prostate Rectum York Masson

The Rank of the 2-Class Group of Some Fields with LargeDegree

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Algebra Colloquium 2022年第2期29卷 181-188页

作者： mohamed mahmoud Chems-Eddin Department of Mathematics Faculty of Sciences Dhar El Mahraz Sidi Mohamed Ben Abdellah UniversityFezMorocco

Let n≥3 be an integer and d an odd square-free *** compute the rank of the 2-class group of some fields of the form L_(n,d)=Q(ζ_(2^(n)),√d)when all the prime divisors of d are congruent to±3(mod 8)or 9(mod 16).

关键词： cyclotomic Z_(2)-extension 2-rank 2-class group

ON SINGULAR EQUATIONS INVOLVING FRACTIONAL LAPLACIAN

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Acta Mathematica Scientia 2020年第5期40卷 1289-1315页

作者： Ahmed YOUSSFI Ghoulam OULD mohamed mahmoud National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez Laboratory of Mathematical Analysis and Applications My Abdellah Avenue Road ImouzerP.O.Box 72 Fes-Principale30000FezMorocco National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez My Abdellah Avenue Road ImouzerP.0.Box 72 Fes-Principale30000FezMorocco

We study the existence and the regularity of solutions for a class of nonlocal equations involving the fractional Laplacian operator with singular nonlinearity and Radon measure data.

关键词： fractional Laplacian singular elliptic equations measure data

Efficient Channel Estimation Techniques for MIMO Systems with 1-Bit ADC

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China Communications 2020年第5期17卷 50-64页

作者： Hany SHussein Shaimaa Hussein Ehab mahmoud mohamed Electrical Engineering Dept. College of EngineeringKing Khalid UniversityAbha 61411King of Saudi Arabia Electrical Engineering Dept. Faculty of EngineeringAswan UniversityAswan 81542Egypt Electrical Engineering Dept. College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir 11991King of Saudi Arabia

With a low resolution 1-bit ADC on its receiver(RX) side, MIMO with 1-bit ADC took a considerable step in the fulfillment of the hardware complexity constrains of the internet of things(IoT) PHY layer design. However, applying 1-bit ADC at MIMO RX results in severe nonlinear quantization error. By which, almost all received signal amplitude information is completely distorted. Thus, MIMO channel estimation is considered as a major barrier towards practical realization of 1-bit ADC MIMO system. In this paper, two efficient sparsity-based channel estimation techniques are proposed for 1-bit ADC MIMO systems, namely the low complexity sparsity-based channel estimation(LCSCE), and the iterative adaptive sparsity channel estimation(IASCE). In these techniques, the sparsity of the 1-bit ADC MIMO channel is exploited to propose a new adaptive and iterative compressive sensing(CS) recovery algorithm to handle the 1-bit ADC quantization effect. The proposed algorithms are tested with the state-of-the-art 1-bit ADC MIMO constant envelope modulation(MIMO-CEM). The 1-bit ADC MIMO-CEM system is chosen as it fulfills both energy and hardware complexity constraints of the IoT PHY layer. Simulation results reveal the high effectiveness of the proposed algorithms in terms of spectral efficiency(SE) and computational complexity. The proposed LCSCE reduces the computational complexity of the 1-bit ADC MIMO-CEM channel estimation by 86%, while the IASCE reduces it by 96% compared to the recent techniques of MIMO-CEM channel estimation. Moreover, the proposed LCSCE and IASCE improve the spectrum efficiency by 76 % and 73 %, respectively, compared to the recent techniques.

关键词： channel estimation 1-bit ADC MIMO sparsity recovery compressive sensing Internet of things

Influence of Fe_(2)O_(3) on the physical,structural and electrical properties of sodium lead borate glasses

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Journal of Advanced Ceramics 2014年第2期3卷 155-164页

作者： Safeya IBRAHIM mohamed mahmoud GOMAA Hussein DARWISH Glass Research Department National Research CentreDokkiCairoEgypt Geophysical Sciences Department National Research CentreDokkiCairoEgypt

The influence of adding Fe_(2)O_(3) at the expense of Na_(2)O in sodium lead borate glasses on the structural,physical and electrical properties have been *** obtained from Fourier transform infrared(FTIR)spectra indicated that Fe_(2)O_(3) plays an important role in converting three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO4].The physical properties such as density and molar volume helped to evaluate the compact structure of the prepared glass samples due to presence of[BO4]*** increase of Fe_(2)O_(3)/Na_(2)O replacements led to increasing the microhardness values and decreasing the thermal expansion coefficients of the studied *** increase of Fe_(2)O_(3)/Na_(2)O replacements generally decreased the AC *** decrease might be due to converting of the three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO_(4)].Dielectric constants of the samples might be an indication of the distortion in the coordinated boron *** obtained experimental data indicated the internal structure of glass network and the change of the structure of the samples from three[BO_(3)]to four coordinated boron atoms[BO4].

关键词： borate glasses Fourier transform infrared(FTIR)spectra microhardness thermal expansion AC electrical properties

数据缺陷条件下支持污水处理厂智能管理的数据增强方法

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环境工程 2024年第6期42卷 153-159页

作者：王建辉廖万山李慧敏冯东郭智威 mohamed S.mahmoud 张冰高旭申渝陈猷鹏重庆工商大学智能制造服务国际科技合作基地重庆400067 重庆南向泰斯环保技术研究院有限公司重庆400069 重庆中法环保研发中心有限公司重庆400010 埃及住房和建筑国家研究中心卫生与环境工程研究所埃及开罗1770 重庆大学环境与生态学院重庆400045

污水处理厂的智能化管理需要高质量、丰富的数据支持。然而,在当前污水处理厂的运维管理中,过度曝气、过量投药及监测问题等导致水厂运维数据的数量和质量存在缺陷,基于此类缺陷数据支持的各种数据驱动模型性能不高。如何提高数据质量... 详细信息

污水处理厂的智能化管理需要高质量、丰富的数据支持。然而,在当前污水处理厂的运维管理中,过度曝气、过量投药及监测问题等导致水厂运维数据的数量和质量存在缺陷,基于此类缺陷数据支持的各种数据驱动模型性能不高。如何提高数据质量和数量对于各类人工智能模型的研究和应用非常关键。提出了一种基于生成对抗网络的污水厂数据增强方法(WP-GAN),以应对数据缺陷问题,并采用一种经典的污水处理厂人工神经网络模型(W-ANN)对所提出的方法进行验证。研究采用的数据集来自某大型城市污水处理厂的厌氧-缺氧-好氧(A2O)工艺,通过数据增强处理将实测数据扩增5倍,以增强前后的数据样本训练W-ANN模型后,模型性能得到显著提升:拟合度从20%提高到65%,最大模拟精度从67.85%提高到75.55%。该方法是一种应对数据缺陷的通用数据增强方法,可为污水厂智能管理的各种数据驱动模型提供更好的数据支持。

关键词：数据增强污水处理生成对抗网络智能管理数据驱动模型

Millimeter-Wave Concurrent Beamforming:A Multi-Player Multi-Armed Bandit Approach

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Computers, Materials & Continua 2020年第12期65卷 1987-2007页

作者： Ehab mahmoud mohamed Sherief Hashima Kohei Hatano Hani Kasban mohamed Rihan Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringAswan UniversityAswan81542Egypt Computational Learning Theory Team RIKEN-Advanced Intelligent ProjectFukuoka819-0395Japan Engineering Department Nuclear Research CenterEgyptian Atomic Energy AuthorityCairo13759Egypt Faculty of Arts and Science Kyushu UniversityFukuok819-0395Japan Electronics and Electrical Communication Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The communication in the Millimeter-wave(mmWave)band,i.e.,30~300 GHz,is characterized by short-range transmissions and the use of antenna beamforming(BF).Thus,multiple mmWave access points(APs)should be installed to fully cover a target environment with gigabits per second(Gbps)***,inter-beam interference prevents maximizing the sum rates of the established concurrent *** this paper,a reinforcement learning(RL)approach is proposed for enabling mmWave concurrent transmissions by finding out beam directions that maximize the long-term average sum rates of the concurrent ***,the problem is formulated as a multiplayer multiarmed bandit(MAB),where mmWave APs act as the players aiming to maximize their achievable rewards,i.e.,data rates,and the arms to play are the available beam *** this setup,a selfish concurrent multiplayer MAB strategy is *** different MAB algorithms,namely,ϵ-greedy,upper confidence bound(UCB),Thompson sampling(TS),and exponential weight algorithm for exploration and exploitation(EXP3)are examined by employing them in each AP to selfishly enhance its beam selection based only on its previous *** a few rounds of interactions,mmWave APs learn how to select concurrent beams that enhance the overall system *** proposed MAB based mmWave concurrent BF shows comparable performance to the optimal solution.

关键词： Millimeter wave(mmWave) concurrent transmissions reinforcement learning multiarmed bandit(MAB)

Martensitic transformation and magnetic properties of aged Ni-Fe-Ga-Ti shape memory alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 867-873页

作者： Nader El-Bagoury mahmoud mohamed Hessien Magdy Abdel Wahab Kaseem Chemistry Department Faculty of Science TAIF University P.O. Box 888 El-Haweyah El-Taif Saudi Arbia Central Metallurgical Research and Development Institute (CMRDI) P.O. Box 87 Helwan Cairo Egypt Head of National Authority for Quality of Education Assurance and Accreditation Nasr City Cairo P.O. Box 11461 Egypt

This article reports the effect of ageing on the microstructure, martensitic transformation, magnetic properties, and mechanical properties of Ni51FelsGa27Ti4 shape memory alloy. There are five specimens of this alloy aged at 573 up to 973 K for 3 h per each. This range of ageing temperature greatly affects the microstructure of the alloy. As the ageing temperature increased from 573 up to 973 K, the microstructure of Ni51FelsGa27Ti4 alloy gradually changed from the entirely martensitic matrix at 573 K to the fully austenitic microstructure at 973 K. The volume fraction of precipi- tated Ni3Ti particles increased with the ageing temperature increasing from 573 to 773 K. Further increasing the ageing temperature to 973 K decreased the content of Ni3Ti in the microstructure. The martensitic transformation tempera- ture was decreased steadily by increasing the ageing temperature. The magnetization saturation, remnant magnetization, and coercivity increased with the ageing temperature increasing up to 773 K. A further increase in ageing temperature decreased these raagnetic properties. Moreover, the hardness values were gradually increased at first by increasing the ageing temperature to 773 K, and then dramatically decreased to the lowest value at 973 K.

关键词： magnetic materials shape memory effect ageing microstructure martensitic transformations magnetic properties hardness

Electrospinning of Nylon-6,6 Solutions into Nanofibers: Rheology and Morphology Relationships

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Chinese Journal of Polymer Science 2014年第6期32卷 793-804页

作者： Ali Abbasi mohamed mahmoud Nasef Matsuura Takeshi Reza Faridi-Majidi Faculty of Chemical Engineering Universiti Teknologi Malaysia Institute of Hydrogen Economy International Campus Universiti Teknologi Malaysia Malaysia-Japan International Institute of Technology International Campus Universiti Teknologi Malaysia Department of Chemical & Biological Engineering University Ottawa Department of Medical Nanotechnology School of Advanced Medical Technologies Tehran University of Medical Sciences

The relationship between the rheological properties of nylon-6,6 solutions and the morphology of their electrospun nanofibers was established. The viscosity of nylon-6,6 in formic acid （90%） was measured in the concentration range of 5 wt%-25 wt% using a programmable viscometer. Electrospinning of nylon-6,6 solutions was carried out under controlled parameters. The chemical structure, morphology and thermal properties of the obtained nanofibers were investigated using Fourier transform infrared spectroscopy （FTIR）, scanning electron microscopy （SEM） and differential scanning calorimetry （DSC）, respectively, Entanglement concentration （ce） was found to be 15 wt% and a power law relationship between specific viscosity and solution concentration was observed with exponents of 2.0 and 3.3 for semi-dilute unentangled （c 〈 ce） and semi-dilute entangled （c 〉 ce） regimes, respectively. The diameter and uniformity of the nanofibers were found to be dependent on the viscosity. Moreover, the average diameter of electrospun nanofibers was found to be dependent on zero shear rate viscosity and normalized concentration （c/ce） in a power law relationship with exponents of 0.298 and 0.816, respectively. For nylon-6,6 solutions, the entanglement concentration （ce = 15 wt%） provides the threshold viscosity required for the formation of a stable polymeric jet during electrospinning and producing uniform beadless fibers. For concentrations less than ce, beaded fibers with some irregularities are formed. DSC analysis showed an increase in crystallinity of all electrospun samples compared to original polymer. Furthermore; Based on FTIR spectroscopy, α phase is dominant in electrospun nanofibers and minor amount offland ）,phases is also available.

关键词： Nylon-6,6 electrospinning Viscosity Nanofibers Entanglement concentration Crystallinity.