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A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.F.Darwish mohamed H.A.Hassan Nagat m.K.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a.m.ssive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGa.m.thod for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturemulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the FTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDF)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

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Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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CLEAN ENERGY 2024年第1期8卷 188-196页

作者： Elnagi, Basem E. Ismaiel, a.m.d m. mansour, Hany S. E. Abd-Alwahab, m. N. Suez Canal Univ Fac Engn Elect Engn Dept Ismailia 41522 Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost converter. It was directly coupled to a single-phase (two levels-four pulses) inverter without a transformer. The pulse-width modulation signal was used to independently regulate every converter phase. The converter was modelled using a.m.TLAB (R)/Simulink (R) environment and an appropriate voltage control method. The analysis features of the suggested circuit were created and, through established experiments, the simulation results were verified. A single-phase (two levels-four pulses) inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage control. It matches the voltage of the network in terms of amplitude and frequency. A sinusoidal pulse-width modulation approach was performed using a single-phase (two levels-four pulses) pulse-width modulation inverter. The results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63 mu s compared with 180 mu s in conventional techniques. A comprehensive model of a proton-exchange membrane fuel cell stack is integrated with a single-phase (two levels-four pulses) inverter without a transformer. Pulse-width modulation is used to independently regulate every converter phase. As a result, the dead time is reduced compared to conventional techniques. Graphical Abstract

关键词： PEm fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter PERFORmANCE SYSTEm

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球周注射皮质激素治疗糖尿病性视乳头病变

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世界核心医学期刊文摘（眼科学分册） 2005年第6期1卷 35-36页

作者： mansour a.m. El-Dairi m.A. Shehab m.A. 张鹏 Department ofOphtha.m.logy AmericanUniversity of Beirut Beirut Lebanon

Purpose. To ascertain the therapeutic effect of periocular corticosteroids in diabetic papillopathy. methods. Prospec-tively, five consecutive adult-onset diabetic patients with symptomatic diabetic papillopathy underwent visual fields and fluorescein angiography before and after superonasal subtenon injection of corticosteroids. Results. The median duration of papillopathy was 2.5 weeks by ophtha.m.scopy and 3 weeks by fluorescein angiography. The median recovery time of best-spectacle-corrected visual acuity was 2 weeks. Two patients developed sequential diabetic papillopathy, and both reported faster visual recovery and better subjective vision in treated eyes. In these two patients, the final best-spectacle-corrected visual acuity and visual evoked responses were comparable between the two eyes, while automated visual fields were less constricted in treated eyes. Complications included ocular hypertension, mild progression of cataract, and mild ptosis in one patient each. Conclusions. Periocular corticosteroids shortened the duration of diabetic papillopathy from a reported median of 5 months to 3 weeks in the present uncontrolled observational study, partly by their angiostatic and antioedema effects at the level of the anterior optic nerve. Intraocular pressure needs to be monitored in eyes receiving periocular corticosteroids.

关键词：球周皮质激素治疗对侧眼球筋膜囊视野损害自动视野计上睑下垂高眼压视觉诱发反应中位病程

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Improved combustion stability of biogas at different CO_(2) concentrations using inhomogeneous partially premixed stratified flames

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Global Energy Interconnection 2024年第4期7卷 486-502页

作者： mohy Saad mansour maged Kiriakos Lili Hao mohamed Amr Serag-Eldin mechanical Power Engineering Department Cairo University1 Gamaa StreetCairo Governorate 12613Egypt mechanical Engineering Department The American University in CairoAUC AveCairo Governorate 11835Egypt College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816P.R.China

Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon *** high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas *** improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this *** thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame *** flame size was reduced by increasing the CO_(2) concentration and the flames became lighter *** flame temperature also decreased with increase in CO_(2) *** stability was reduced by increasing the CO_(2) ***,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the ***,the IPPS mode of combustion should be suitable for the combustion and stabilization of *** should support the design of highly stabilized biogas turbulent flames independent of CO_(2) *** data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant.

关键词： Biogas Renewable energy Effect of CO_(2) Combustion stability Burner design Renewable fuels Partial premixed

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Use of ketamine for severe asthma exacerbation in a pregnant patient with persistent bronchospa.m. A case report

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Emergency and Critical Care medicine 2024年第3期4卷 130-133页

作者： Johnson m. Abbas m. Abdo J. mansour m. Jones J. Pha.m.cy Department Beaumont Health Dearborn MI United States Emergency Center Beaumont Health Dearborn MI United States

Background Estimated 4%-8% of pregnancies are complicated by asthma. Adequate management in this population is critical to minimize complications. Patients presenting with asthma exacerbation are typically managed with standard bronchodilators and systemic corticosteroids. However, additional agents may be used in patients with refractory asthma exacerbation. Ketamine has been used in refractory bronchospa.m. although its efficacy in published literature is heterogeneous. Case Presentation We present a case of a pregnant patient with severe asthma exacerbation refractory to standard and salvage trea.m.nt who achieved termination of bronchospa.m.with ketamine infusion. Conclusion After receiving ketamine infusion for several days, the patient had improved air flow and achieved successful extubation, without experiencing rebound bronchospa.m. Although this individual clinical case alone cannot change guidelines or directives to use in refractory asthma exacerbations, it offers a possible trea.m.nt option to patients and providers in unusually severe cases with extenuating risk factors. © Wolters Kluwer Health, Inc. All rights reserved.

关键词： Asthma Bronchospa.m. Case Report Ketamine Pregnancy

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先天性心脏病患者眼部病理表现

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世界核心医学期刊文摘（眼科学分册） 2005年第6期1卷 33-34页

作者： mansour a.m. Bitar F.F. Traboulsi E.I. 郭长梅 Department of Ophtha.m.logy American University of Beirut Beirut Lebanon

Purpose. To describe the ocular findings in subjects with congenital heart disease (CHD). methods. In a prospective study, the same observer examined 240 consecutive patients with CHD a.m.tted to the medical centre. Two independent geneticists performed identification of syndromes. Results. The commonest anatomic cardiac anomalies were ventricular or atrial septal defects (62), tetralogy of Fallot (39), pulmonary stenosis (25), and transposition of the great arteries (24). The heart lesions were divided physiologically into volume overload (90), cyanotic (87), and obstructive (63). In all, 105 syndromic subjects included the velocardiofacial syndrome (18), Down’ s syndrome (17), CHARGE association (6), DiGeorge syndrome (5), Williams syndrome (3), Edwards syndrome (3), Noonan syndrome (3), VACTERL association (2), and Patau syndrome (trisomy 13) (2). The paediatric team recognized 51 patients as syndromic. Two independent geneticists recognized additional 54 patients as syndromic. Positive eye findings were present in 55% (132) and included retinal vascular tortuosity (46), optic disc hypoplasia (30), trichomegaly (15), congenital ptosis (12), strabismus (11), retinal ha.m.rrhages (8), prominent eyes (7), and congenital cataract (6). There was a strong correlation between the retinal vascular tortuosity and both a low ha.m.tocrit (P=0.000) and a low arterial oxygen saturation (P=0.002). Conclusions. Patients with CHD are at a high risk for ocular pathology and need screening for various ocular abnormalities.

关键词：先天性心脏病视网膜血管肺动脉瓣狭窄大动脉转位房间隔缺损视网膜出血法洛四联症联合征三体室间隔缺损

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Evaluating transient behaviour of large-scale photovoltaic systems during lightning events using enhanced finite difference time domain method with variable cell size approach

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HIGH VOLTAGE 2024年第3期9卷 636-647页

作者： Hetita, Ibrahim mansour, Diaa-Eldin A. Han, Yang Yang, Ping Wang, Congling Darwish, mohamed m. F. Lehtonen, matti Zalhaf, Amr S. Univ Elect Sci & Technol China UESTC Sch Mech & Elect Engn Chengdu Peoples R China Helwan Univ Fac Engn Elect Power & Machines Engn Dept Cairo Egypt Tanta Univ Fac Engn Elect Power & Machines Engn Dept Tanta Egypt Egypt Japan Univ Sci & Technol Fac Engn Dept Elect Power Engn Alexandria Egypt Benha Univ Fac Engn Shoubra Dept Elect Engn Cairo Egypt Aalto Univ Sch Elect Engn Dept Elect Engn & Automation Espoo Finland GmC Dept Med Srinagar Jammu And Kashm India

Photovoltaic (PV) arrays are usually installed in open areas; hence, they are vulnerable to lightning strikes that can result in cell degradation, complete damage, service disruption, and increased maintenance costs. As a result, it is imperative to develop an effective and efficient lightning protection system by evaluating the transient behaviour of PV arrays during lightning events. The a.m.is to evaluate the transient analysis of large-scale PV systems when subjected to lightning strikes using the finite difference time domain (FDTD) technique. Transient overvoltages are calculated at various points within the mounting system. To optimise the FDTD method's execution time and make it more suitable for less powerful hardware, a variable cell size approach is employed. Specifically, larger cell dimensions are used in the earthing system and smaller cell dimensions are used in the mounting system. The FDTD method is utilised to calculate the temporal variation of transient overvoltages for large-scale PV systems under different scenarios, including variations in the striking point, soil resistivity, and the presence of a.m.tal frame. Simulation results indicate that the highest transient overvoltages occur at the striking point, and these values increase with the presence of a PV metal frame as well as with higher soil resistivity. Furthermore, a comparison is performed between the overvoltage results obtained from the FDTD approach and the partial element equivalent circuit (PEEC) method at the four corner points of the mounting systems to demonstrate the superior accuracy of the FDTD method. Besides, a laboratory experiment is conducted on a small-scale PV system to validate the simulation results. The calculated overvoltages obtained from the FDTD and PEEC methods are compared with the measured values, yielding a.m.an absolute error of 5% and 11% for the FDTD and PEEC methods, respectively, thereby confirming the accuracy of the FDTD simulation model.

关键词： FDTD mETHOD mODEL

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mental health status among COVID-19 patients survivors of critical illness in Saudi Arabia:A 6-month follow-up questionnaire study

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World Journal of Clinical Cases 2024年第15期12卷 2560-2567页

作者： Abdullah m Alha.m.d Namareq F Aldardeer Abdulaziz Alqahtani moha.m.d H Aljawadi Bushra Alnefaie Raghad Alonazi mansour a.m.qbil Abdulra.m.n Alsaadon Rakan m Alqahtani Rashid Alballaa Bader Alshehri moha.m.d I Alarifi Fahad D Alosa.m. Department of Clinical Pha.m.cy College of PharmacyKing Saud UniversityRiyadh 12372Saudi Arabia Department of Pha.m.cy Services King Faisal Specialist Hospital and Research CentreJeddah 21499Saudi Arabia Corporate Department of Pha.m.cy Services King Saud University Medical CityRiyadh 12372Saudi Arabia College of Pha.m.cy King Saud UniversityRiyadh 12372Saudi Arabia Department of Critical Care medicine College of MedicineKing Saud UniversityRiyadh 12372Saudi Arabia Department of Psychiatry College of MedicineKing Saud UniversityRiyadh 12372Saudi Arabia

BACKGROUND Psychological assessment after intensive care unit(ICU)discharge is increasingly used to assess patients'cognitive and psychological ***,few studies have examined those who recovered from coronavirus disease 2019(COVID-19).There is a paucity of data from the middle East assessing the post-ICU discharge mental health status of patients who had *** To evaluate anxiety and depression among patients who had severe *** This is a prospective single-center follow-up questionnaire-based study of adults who were a.m.tted to the ICU or under ICU consultation for>24 h for *** patients were contacted via *** patient’s anxiety and depression six months after ICU discharge were assessed using the Hospital Anxiety and Depression Scale(HADS).The primary outcome was the mean HADS *** secondary outcomes were risk factors of anxiety and/or *** Patients who were a.m.tted to the ICU because of COVID-19 were screened(n=518).Of these,48 completed the *** mean age was 56.3±17.2 *** patients(62.5%)were *** main comorbidities were endocrine(n=24,50%)and cardiovascular(n=21,43.8%)*** mean overall HADS score for anxiety and depression at 6 months post-ICU discharge was 11.4(SD±8.5).A HADS score of>7 for anxiety and depression was detected in 15 patients(30%)and 18 patients(36%),*** from the multivariable ordered logistic regression demonstrated that vasopressor use was associated with the development of anxiety and depression[odds ratio(OR)39.06,95% confidence interval:1.309-1165.8;Pmonths after ICU discharge,30% of patients who had COVID-19 demonstrated a HADS score that confirmed anxiety and *** compare the psychological status of patients following an ICU a.m.ssion(with vs without COVID-19),further studies are warranted.

关键词： COVID-19 Critically ill Anxiety Depression HADS Saudi Arabia

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Genotypic effects on accelerated propagation of oil pa.m.breeding materials selected(Elaeis guineensis jacq.)using somatic embryogenesis

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Oil Crop Science 2024年第2期9卷 111-120页

作者： Retno Puji Astari moha.m.d Basyuni Luthfi a.m. Siregar Revandy I.m. Damanike Deni Arifiyanto Dadang Affandi Indra Syahputra Doctoral Program of Agricultural Sciences Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia PT.Socfin Indonesia Jl.K.L.Yos Sudarso No.106Medan20244North SumatraIndonesia Department of Forestry Faculty of ForestryUniversitas Sumatera UtaraJl.Tri Dharma Ujung No.1Medan20155North SumatraIndonesia Center of Excellence for mangrove Universitas Sumatera UtaraMedan20155Indonesia Department of Agrotechnology Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia

Vegetable oil production from oil pa.m.Elaeis guineensis Jacq.)is an important industry due to the rising demand every *** somatic embryogenesis culture can propagate oil pa.m.duplicate as parent plant,which can be selected as breeding material to produce new planting germpla.m.with high production or disease *** study a.m. to evaluate the genotypic effect of somatic embryogenesis,while immature leaflets were employed as *** culture used embryo induction medium based on murashige and Skoog(mS)modifications that contained 5 mg/L Naphthalene Acetic acid(NAA)and 0.5 mg/L Benzyl Amino Purine(BAP).The genotypic effect was statistically significant in the percentage of callus induction,producing somatic embryos,and germination *** this study,we successfully cloned thirteen oil pa.m.genotypes(GE-02,GE-03,GE-06,GE-07,GE-09,GE-23,GE-24,GE-27,GE-28,GE-32,GE-33,GE-34,and GE-35),with the highest number of somatic embryos formed on GE-27 with a percentage of 70.1%.The cloning was successful in accelerating the propagation of oil pa.m.for materials breeding programs to create new varieties with high production and disease *** is necessary to observation the performance of these clones in the field in terms of mantle flower appearance.

关键词： Somatic embryogenesis Oil palm Genotypic effect Support breeding

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Enhancing cotton resilience to challenging climates through genetic modifications

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Journal of Cotton Research 2024年第2期7卷 196-206页

作者： a.m.D Ali Ijaz KHAN Azeem Iqbal NEGm mohamed a.m. IQBAL Rida AZHAR muha.m.d Tehseen KHAN Sultan Habibullah RANA Iqrar a.m.d Department of Plant Breeding and Genetics University of AgricultureFaisalabadFaisalabad 38000Pakistan Cotton Research Institute-Giza GizaEgypt Centre for Advanced Studies in Agriculture and Food Security University of AgricultureFaisalabadFaisalabad 38000Pakistan Centre of Agricultural Biochemistry and Biotechnology University of AgricultureFaisalabadFaisalabad 38000Pakistan School of Agriculture Sciences Zhengzhou UniversityZhengzhou 450000China

Cotton is one of the most important fiber crops that plays a vital role in the textile *** production has been unstable over the years due to climate change induced biotic stresses such as insects,diseases,and weeds,as well as abiotic stresses including drought,salinity,heat,and *** breeding methods have been used to breed climate resilient cotton,but it requires a considerable amount of time to enhance crop tolerance to insect pests and changing climatic conditions.A promising strategy for improving tolerance against these stresses is genetic *** review article discusses the role of genetic engineering in cotton *** essential concepts and techniques include genome editing via clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(CRISPR-Cas9),overexpression of target genes,downregulation using RNA interference(RNAi),and virus-induced gene silencing(VIGS).Notably,the Agrobacterium-mediated transformation has made significant contributions to using these techniques for obtaining stable transgenic plants.

关键词： Cotton Genome editing Drought Salinity Heat

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