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Economic Feasibility Assessment of Motorized PV Louver System Considering the Near Shading Parameter, Array Incidence Losses and Other Environmental Factors

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World Journal of Engineering and Technology 2024年第3期12卷 540-551页

作者： Hussein safwat Hasan Humor Hwang Department of Information and Communications Engineering Myongji University Yongin Republic of Korea

Seoul has good weather settings for incorporating renewable energies, hence, given its small land area living mode was mostly set in an apartment condition it is an ideal place for building applied photovoltaic (BAPV) for solar energy harvesting. On the other hand, the BAPV energy self-consumption hasn’t been thoroughly examined considering the overall energy consumption requirement. Therefore, presented in this communication are the viability of PVL to produce electricity from solar energy and insights on modulating and improving energy harvesting efficiency. To accomplish this objective, three major factors were considered: 1) the photovoltaic (PV) positioning;2) the solar tracking scenario;and 3) the mechanistic system energy consumption. The overall louver energy generation was thoroughly scrutinized from the net energy conception of the BAPV up to the mechanistic module energy expenditure. This work intends to provide insights into the economic feasibility of BAPV assessing its technological profitability in the specified location and building size.

关键词： Photovoltaic Louvers Energy Consumption Tracking System Building Integrated Photovoltaic PVsyst

Influence of anodization conditions on deposition of Hydroxyapatite on α/β Ti alloys for Osseointegration: Atomic Force Microscopy Analysis

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Transactions of Nonferrous Metals Society of China 2024年

作者： Rania E.Hammam Engie M.safwat Soha A.Abdel-Gawad Madiha Shoeib Shimaa El-Hadad Faculty of Engineering， Modern University for Technology and Information (MTI) Restorative and Dental Materials Department， National Research Centre Giza Chemistry Department， Faculty of Science， Cairo University Central Metallurgical Research and Development Institute P.O.87

Integrating titanium-based implants with the surrounding bone tissue remains challenging. This study aims to explore the impact of different anodization voltages （20-80V） on the surface topography of two-phase （α/β） Ti alloys and to produce TiO2films with enhanced bone formation abilities. Scanning electron microscopy coupled with energy dispersive spectroscopy （SEM-EDS） and atomic force microscopy （AFM） were applied to investigate the morphological， chemical， and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite （HA） on their surfaces. Results disclosed that the surface roughness of TiO2films formed on Ti-6Al-7Nb alloys was superior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highest yields of HA after immersion in SBF with enhanced HA surface coverage. The developed HA layer had a mean thickness of 128.38 ± 18.13 μm， suggesting its potential use as an orthopedic implantable material due to its promising bone integration and， hence， remarkable stability inside the human body.

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Electrochemical anodization of cast titanium alloys in oxalic acid for biomedical applications

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Frontiers of Chemical Science and Engineering 2024年第1期18卷 13-24页

作者： Engie M.safwat Soha A.Abdel-Gawad Madiha A.Shoeib Shimaa El-Hadad Restorative and Dental Materials Department National Research CentreGiza 12622Egypt Chemistry Department Faculty of ScienceCairo UniversityGiza 12613Egypt Central Metallurgical Research and Development Institute Helwan 11421Egypt

Titanium and its alloys have numerous biomedical applications thanks to the composition and morphology of their oxide *** this study,the colorful oxide films were formed by anodizing cast Ti-6Al-4V and Ti-6Al-7Nb alloys in a 10%oxalic acid solution for 30 s at different voltages(20–80 V)of a direct current power *** force microscopy was used as an accurate tool to measure the surface roughness of thin films on the nanometer *** electron microscopy and X-ray diffraction were performed to analyze surface morphology and phase *** to the results,the produced titanium oxide layer showed high surface roughness,which increased with increasing anodizing *** impact of anodizing voltages on the color and roughness of anodized layers was *** corrosion resistance of the anodized samples was studied in simulated body fluid at pH 7.4 and a temperature of 37℃ utilizing electrochemical impedance spectroscopy and the potentiodynamic polarization *** anodized samples for both alloys at 40 V were at the optimal voltage,leading to a TiO_(2) layer formation with the best compromise between oxide thickness and corrosion ***,findings showed that TiO_(2) films produced on Ti-6Al-7Nb alloys had superior surface roughness properties compared to those of Ti-6Al-4V alloys,making them more appropriate for orthopedic *** the obtained data and the fruitful discussion,it was found that the utilized procedure is simple,low-cost,and ***,anodization in 10%oxalic acid proved a viable alternative for the surface finishing of titanium alloys for biomedical applications.

关键词： DC anodization Ti-6Al-4V alloy Ti-6Al-7Nballoy oxidefilm corrosion

Improved Multi-party Quantum Key Agreement with Four-qubit Cluster States

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Computers, Materials & Continua 2022年第10期73卷 225-232页

作者： Hussein Abulkasim Eatedal Alabdulkreem safwat Hamad Faculty of Science New Valley UniversityEl-Kharga&the Academy of Scientific Research and TechnologyCairoEgypt College of Computer and Information Sciences Princess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia Faculty of Computer and Information Sciences Ain Shams UniversityCairoEgypt

Quantum key agreement is a promising key establishing protocol that can play a significant role in securing 5G/6G communication ***,Liu et al.(Quantum Information Processing 18(8):1-10,2019)proposed a multi-party quantum key agreement protocol based on four-qubit cluster states was *** aim of their protocol is to agree on a shared secret key among multiple remote *** et *** four-qubit cluster states to be the quantum resources and the X operation to securely share a secret *** addition,Liu et al.’s protocol guarantees that each participant makes an equal contribution to the final *** authors also claimed that the proposed protocol is secure against participant attack and dishonest participants cannot generate the final shared key ***,we show here that Liu et *** is insecure against a collusive attack,where dishonest participants can retrieve the private inputs of a trustworthy participant without being ***,the corresponding modifications are presented to address these security flaws in Liu et al.’s protocol.

关键词： Quantum key agreement 5G/6G communication networks collusive attacks quantum cryptography

Structural and Tectonic Evolution of El-Faiyum Depression,North Western Desert,Egypt Based on Analysis of Landsat ETM+,and SRTM Data

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Journal of Earth Science 2011年第1期22卷 75-100页

作者： Timothy M Kusky Talaat M Ramadan Mahmoud M Hassaan safwat Gabr Three Gorges Research Center for Geo-hazard State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences The Geological Applications and Mineral Resources Division National Authority for Remote Sensing and Space Sciences (NARSS) Cairo Egypt

False color Landsat ETM＋（bands 7, 4, 2 in RGB） and SRTM images of the EI-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and N-S. Airborne magnetic data reveal some E-W subsurface faults which are not recognized on Landsat ETM＋ and SRTM images. Ratio images （5/7, 3/1, 4/3） and （5/7, 5/1, 4） were used for lithological discrimination of different rock types. The EI-Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of EI-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits （comprising fluviatile sediments and basalt sheets） and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1 ： 100 000 using Landsat ETM＋ and SRTM images coupled with extensive field work. The major structural trends are E-W, ENE, NS and NW--the same trends observed elsewhere in North Africa from NW Sudan to NE Egypt including north and central Sinai. EI-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, folds, push-up structures, and basins. Qarun Lake is located in the northern part of EI-Faiyum depression, at a right-step between two strands of the NE striking fault system. We have suggested elsewhere that EI-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The E-W structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of t

关键词： Egypt EI-Faiyum Syrian arc fold belt pull-apart basin Western Desert of Egypt.

The Utilization of Eucalyptus Oil for Reducing Methane Production in Ruminants under in Vitro Conditions

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The Utilization of Eucalyptus Oil for Reducing Methane Produ...

作者： safwat Mohamed Abdelrahman Ahmed Attia 吉林农业大学

学位级别：硕士

畜牧业产生的甲烷是引起全球变暖的主要因素。地球气候变暖成为全球重要问题之一。本研究中在体外条件下研究不同浓度的桉叶油对瘤胃中生产甲烷的抑制作用。试验设计为:不同精粗比的饲粮,分别为70:30和60:40。饲粮干物质中桉叶油的浓度... 详细信息

畜牧业产生的甲烷是引起全球变暖的主要因素。地球气候变暖成为全球重要问题之一。本研究中在体外条件下研究不同浓度的桉叶油对瘤胃中生产甲烷的抑制作用。试验设计为:不同精粗比的饲粮,分别为70:30和60:40。饲粮干物质中桉叶油的浓度分别为0 mL/kg、2 mL/kg、4 mL/kg、6 mL/kg、8 mL/kg和10 mL/kg。试验采用的瘤胃原液从两只健康瘘管绵羊获取,分别在3 h、6 h、9 h、12 h、24 h、36 h、48 h和72 h,检测气压(GP)、甲烷产量(CH4)。发酵(72 h)结束后,检测挥发性脂肪酸(VFA)、氨态氮(NH3)、干物质降解率(DMD)及有机物降解率(OMD)、pH值和原生动物数等。结果表明,不同浓度的桉叶油处理条件下,甲烷产量有所降低(P<0.05)。在精粗比30:70的处理中,2 mL/kg组的甲烷产量较对照组减少32%,10 mL/kg组的甲烷产量较对照组减少38%。在精粗比60:40的处理中,2 mL/kg组的甲烷产量较对照组减少42%,10 mL/kg组的甲烷产量较0 mL/kg组减少46%。在所有精粗比处理中,通过提高桉叶油的浓度,与0 mL/kg组相比,原虫数量显著下降(P<0.05)。NH3浓度较0 mL/kg组下降,在精粗比为60:40组中不显著,在70:30中显著(P<0.05)。在所有精粗比处理中,随着桉叶油浓度的提高,A/P值、DMD和OMD都显著下降(P<0.05)。除了精粗比70:30处理中的10 mL/kg组,其他各组的pH值没有显著差异。综上,2 mL/kg组为效率最高组。该浓度的桉叶油降低甲烷气体为最佳浓度。同时成本也是最低的。

关键词：污染瘤胃桉叶油甲烷反刍动物

Fetal Thigh Circumference versus Fetal Abdominal Subcutaneous Tissue Thickness in Prediction of Fetal Weight in Term Pregnant Women

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Open Journal of Obstetrics and Gynecology 2023年第9期13卷 1580-1594页

作者： Mohamed El-Mandooh Aya Hassan Sarah safwat Department of Obstetrics and Gynecology Faculty of Medicine Ain Shams University Cairo Egypt Faculty of Medicine Alexandria University Alexandria Egypt

Background: Fetal weight estimation by ultrasound is an important factor in obstetrics;it is directly related to the gestational age which helps to plan the mode of delivery and labor management. Objective: to compare between fetal thigh circumference (TC) and abdominal subcutaneous tissue thickness (SCT) in estimating birthweight in term pregnant women. Patients and Methods: This prospective cohort study was conducted at outpatient clinic or emergency room, Obstetrics and Gynecology Department, Faculty of Medicine, Ain Shams University Maternity Hospitals from March 2022 until May 2023. During this study, 100 term pregnant females with gestational age 37 - 40 weeks attended El Demerdash Maternity Hospital and scheduled for delivery either at outpatient clinic or emergency room were enrolled, after consenting each of them. Basic fetal biometry was performed by an expert and professional medical personnel to ensure the accuracy of examination results. Fetal abdominal subcutaneous thickness and fetal thigh circumference were measured for assessment of gestational age and correlated with actual fetal body weight. In the current study, three formulas;Hadlock, Vintzileos’ and SCT formula were correlated with actual fetal body weight after birth. Results: The present study revealed that TC formula is closer to the actual birth weight, followed by Hadlock formula, while the SCT formula is the furthest from it. Conclusion: To increase the accuracy of birth estimations, regular ultrasound examinations should include fetal thigh circumference measurement.

关键词： Fetal Thigh Circumference Fetal Abdominal Subcutaneous Thickness Fetal Weight Term Pregnancy

Induction of Labor at 39 Weeks versus Expecting Labour till 41 Weeks: Randomized Controlled Trial on Class I Obese Egyptian Women, with Mode of Delivery Being a Study Endpoint

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Open Journal of Obstetrics and Gynecology 2019年第6期9卷 878-887页

作者： M. Samy Sarah safwat Faculty of Medicine Ain Shams University Cairo Egypt

Background: Maternal obesity is reported to be associated with increased incidence of gestational diabetes mellitus and hypertension. These cause failure of labour induction, leading to higher incidence of cesarean section (CS). The aim of this study was to assess which reduces CS rate, labor induction at 39 weeks or leaving women for spontaneous labor onset till 41 weeks. Methodology: A randomized controlled trial was conducted in Ain Shams Maternity Hospital in Egypt from 2016 to 2018. Study population consisted of 200 term primigravida pregnant obese women delivered in Ain Shams Maternity Hospital. They were divided into two groups: Group A: induction of labor at 39 + 0 weeks (n = 100) by vaginal administration of 25 μg misoprostol (PGE1) every 6 hours for 5 doses;Group B: waiting spontaneous labor onset till 41 + 0 weeks (n = 100), and if no spontaneous labor occurred at 41 weeks, induction was performed in the same way. Results: Induction (Group A) vs. waiting spontaneous labor (Group B) showed the followings, which were significant: CS: 22% vs 39%, p = 0.009;maternal birth injury: 4% vs 12%, p = 0.037;non-assisted vaginal deliveries: 93.6% vs 78.7%, p = 0.034;APGAR scores at 1 & 5 min: 7.6 ± 0.8 vs 7.3 ± 1.1 p = 0.038, 8.4 ± 1.0 vs 8.1 ± 1.3 p = 0.040, respectively;birth weight;3.3 ± 0.1 vs 3.5 ± 0.2 kg, p < 0.001. The following did not show significance between Group A vs Group B but Group A showed lower incidence;postpartum hemorrhage: 3% vs 5%, blood transfusion: 1% vs 3%. Conclusion: CS rate was significantly lower in women with induction of labor at 39 weeks than those waiting for spontaneous labor onset till 41 weeks in obese Egyptian pregnant women.

关键词： Obesity Induction Cesarean Section Vaginal Delivery

The Influence of Friction Factor on the Convective and Radiative Heat Transfer in Inclined Cylindrical Annulus

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Journal of Energy and Power Engineering 2013年第11期7卷 2027-2036页

作者： Manal Hadi Al-Hafidh Lina Senan safwat Department of Mechanical Engineering Faculty of Engineering Baghdad University College of Engineering University of Baghdad

The effect of friction factor on the unsteady state mixed convective-radiative heat transfer in an inclined cylindrical annulus is investigated from continuity, momentum and energy equations. The outer cylinder is kept at a constant temperature while the inner cylinder is heated with constant heat flux. The governing equations are normalized and solved using the vorticity-stream function and the BFC （body fitted coordinates） methods. The two heat transfer mechanisms of convection and radiation are treated independently and simultaneously. A computer program （Fortran 90） was built to calculate Nusselt number （Nu） and friction factorffor unsteady state condition for fluid Prandtl number fixed at （Pr = 0.7）（for air as working fluid） with radius ratio （/~ = 2.6）, Rayleigh number （0 〈 Ra 〈 103）, Reynolds number （50 〈 Re 〈 2,000）, conduction-radiation parameter （0 〈 N 〈 10）, optical thickness （0 〈 l＂〈 10） and different annulus inclination with horizontal plane （0~ _〈 d 〈 90~） for concentric cylindrical annulus. For the range of parameters considered, results show that radiation enhance heat transfer. It is also indicated in the results that as 3 increasefwill be decrease and also when Re increasefwill be decrease for any value of Ra causing increase in heat transfer. The maximum value off can be recognized at ~ = 90~ and the minimum value at 6 = 0~ for low Re. There is an optimum value of annulus inclination that gives maximum value of Nu, this maximum value appears at 90~ of annulus inclination comparison of the result with the previous work shows a good agreement.

关键词： Laminar flow mixed convection radiation inclined annulus friction factor.