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The Effect of Atrial Septal Defect Closure on Cardiac Volumetric Changes in Adults, Transcatheter Versus Surgical Closure, a Pilot Cardiac Magnetic Resonance Study

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Congenital Heart Disease 2023年第6期18卷 679-691页

作者： amr mansour Noha M.Gamal Alaa M.Nady amr Ibraheem Dalia M.Salah Khaled M.El-Maghraby Cardiology Department Congenital and Structural Heart Disease UnitAin Shams University HospitalsFaculty of MedicineAin Shams UniversityCairoEgypt Cardiology Department Faculty of MedicineAssuit UniversityAssuitEgypt Cardiothoracic Surgery Department Faculty of MedicineAssuit UniversityAssuitEgypt Anesthesia Department Faculty of MedicineAssuit UniversityAssuitEgypt

Background:Closure of an atrial septal defect(ASD)reduces right-side heart volumes by abolishing shunting with simultaneous improvement of the left ventricle(LV)ﬁlling and functions due to ventricular interdependence,thereby improving ***,studies conducted on atrial volume changes after ASD closure are *** magnetic resonance(CMR)is considered as the gold standard method for measuring cardiac volume and ***:We aimed to study the effect of transcatheter and surgical closure of secundum ASD on cardiac volumes and systolic functions as well as the fate of tricuspid regurgitation(TR),using CMR ***:We prospectively enrolled 30 adult patients with isolated secundum ASD who were referred to ASD *** evaluation of cardiac chambers indexed volumes,systolic function,myocardial mass index,and tricuspid regurgitant fraction were done at before and 6 months after ***:RV volumes decreased in both groups when compared to baseline(p-value 0.001),the device group had more reduction in volumes and more improvement in RV function after closure(p-value 0.001)when compared to the surgical *** changes in the RV mass index were insigniﬁcant between both groups(p-value 0.31).Functional TR improved to the same extent in both *** ventricular end diastolic volume index(LVEDVI)and LV mass index increased sig-niﬁcantly in both groups when compared to baseline in both groups but with no difference between groups p-value 0.01),left ventricular end systolic volume index(LVESVI)changes were insigniﬁ*** systolic function improved in patients who underwent device closure only(63.53±3.85 vs.67.13±4.34,p-value 0.01).There was a signiﬁcant reduction in right atrial(RA)volumes and an insigniﬁcant decrease in left atrial(LA)volumes,with no difference between ***:Transcatheter and surgical secundum ASD closure resulted in volumetric changes in some cardiac chambers with better improvement in bi-ventricular

关键词： Atrial septal defect closure cardiac volumetric changes functional tricuspid regurgitation cardiac CMR

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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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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： Ibrahim Hetita Diaa-Eldin A.mansour Yang Han Ping Yang Congling Wang Mohamed M.F.Darwish Matti Lehtonen amr S.Zalhaf School of Mechanical and Electrical Engineering University of Electronic Science and Technology of China(UESTC)ChengduChina Electrical Power and Machines Engineering Department Faculty of EngineeringHelwan UniversityCairoEgypt Electrical Power and Machines Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Department of Electrical Power Engineering Faculty of EngineeringEgypt-Japan University of Science and TechnologyAlexandriaEgypt Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland

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 *** a result,it is imperative to develop an effective and efficient lightning protection system by evaluating the transient behaviour of PV arrays during lightning *** aim is to evaluate the transient analysis of large-scale PV systems when subjected to lightning strikes using the finite difference time domain(FDTD)*** overvoltages are calculated at various points within the mounting *** optimise the FDTD method's execution time and make it more suitable for less powerful hardware,a variable cell size approach is ***,larger cell dimensions are used in the earthing system and smaller cell dimensions are used in the mounting *** 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 metal *** 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 ***,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 ***,a laboratory experiment is conducted on a small-scale PV system to validate the simulation *** calculated overvoltages obtained from the FDTD and PEEC methods are compared with the measured values,yielding a mean 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： transient behaviour finite

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A numerical investigation into the effect of altering compression ratio, injection timing, and injection duration on the performance of a diesel engine fuelled with diesel-biodiesel-butanol blend

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Clean Energy 2024年第5期8卷 73-96页

作者： Abdulkarim Youssef amr Ibrahim Mechanical Engineering Department Beirut Arab University115020 BeirutLebanon Mechanical Engineering Department Alexandria UniversityAlex 21544Egypt

Using renewable fuels for diesel engines can reduce both air pollution and dependence on fossil fuels.A computer simulation was constructed to predict the performance,combustion characteristics,and NOx emissions of a diesel engine fuelled with diesel-biodiesel-butanol *** simulation was validated by comparing the modelling results against experimental data and a good agreement between the results was *** fuels used for the validation were diesel(B0),biodiesel(B100),diesel-biodiesel blend(B50),and two diesel-biodiesel-butanol blends with 45%diesel-45%biodiesel-10%butanol(Bu10)and 40%diesel-40%biodiesel-20%butanol(Bu20)by *** results showed that the addition of butanol reduced NOx emissions but deteriorated the engine *** aim of the current work was the numerical optimization of the different parameters to enhance the engine performance while using butanol to decrease NOx *** engine compression ratio(CR)varied from 14 to 24,in increments of *** injection timing(IT)was reduced from 30°before top dead centre(bTDC)to 5°bTDC in increments of 5°.Also,the fuel injection duration(IDur)was extended from 20°to 50°in increments of 10°.Results showed that the increase in the CR improved engine performance for the two investigated fuels,Bu10 and *** maximum engine brake power(BP),thermal efficiency(BTE),and minimum brake-specific fuel consumption(BSFC)of 1.46 kW,32.3%,and 0.273 kg/kWh respectively,were obtained when the Bu10 fuel was injected under the optimum conditions of 24 CR,15°bTDC IT,and 40°*** these optimum conditions,the BP,BTE,and BSFC improved by 3%-3.5%for Bu10 and Bu20 fuel blends compared with the base engine conditions of a CR of 22,30°IDur,and 10°bTDC *** heat release rate during the premixed phase increased when the IT was advanced,while the mixing-controlled combustion phase was enhanced when the IT was *** emissions increased with increasing CR,while both an increase in IDur at con

关键词： compression ratio injection timing injection duration butanol biodiesel diesel

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Node Sociability Based Intelligent Routing for Post-Disaster Emergency Networks

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China Communications 2024年第8期21卷 104-114页

作者： Li Jiameng Xiong Xuanrui Liu Min amr Tolba School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Graduate School of Information Production and SystemsWaseda UniversityFukuoka 808-0135Japan School of Communications and Information Engineering Chongqing College of Mobile CommunicationChongqing 401520China Computer Science Department Community CollegeKing Saud UniversityRiyadh 11437Saudi Arabia

In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are *** the“store-carry-forward”mechanism characteristic of Delay Tolerant Networks(DTNs)can transmit data from Internet of things devices to more reliable base stations or data centres,it also suffers from inefficient data transmission and excessive transmission *** address these challenges,we propose an intelligent routing strategy based on node sociability for post-disaster emergency network ***,we introduce an intelligent routing strategy based on node intimacy,which selects more suitable relay nodes and assigns the corresponding number of message copies based on comprehensive utility ***,we present an intelligent routing strategy based on geographical location of nodes to forward message replicas secondarily based on transmission utility ***,experiments demonstrate the effectiveness of our proposed algorithm in terms of message delivery rate,network cost ratio and average transmission delay.

关键词： delay tolerant networks Internet of things node sociability routing strategy

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Asphaltene onset pressure measurement and calculation techniques:A review

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Petroleum 2024年第2期10卷 191-201页

作者： Sherif Fakher amr Yousef Aseel Al-Sakkaf Shams Eldakar Petroleum and Energy Engineering The American University in CairoCairoEgyp

Asphaltene precipitation can result in several production,operational,and transportation problems during oil *** asphaltene precipitates and deposits,it can reduce reservoir permeability,damage wellbore equipment,and plug the *** is therefore extremely important to evaluate the conditions at which asphaltene precipitation occurs;this is referred to as the asphaltene onset *** onset pressure has been measured using many different experimental *** have also been many attempts along the years to predict asphaltene onset pressure using mathematical correlations and *** research provides an up-to-date comprehensive review of the methods by which asphaltene onset pressure can be measured using laboratory experiments and mathematical *** research explains the main mechanisms of all the laboratory experiments to measure asphaltene onset pressure under static conditions and how to conduct them and highlights the advantages and limitations of each *** research also provides a summary of the commonly used mathematical models to quantify asphaltene onset pressure directly and indirectly.

关键词： Asphaltene onset measurement

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Cognitive-emotional feasibility of the effect of visual quality of building form on promoting the sense of place attachment(Case study:Cultural iconic buildings of Iran’s contemporary architecture)

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Frontiers of Architectural Research 2024年第1期13卷 37-56页

作者： Narmin Ariannia Negar Naseri mansour Yeganeh Digital Architecture and Artificial Intelligence Lab Department of ArchitectureTarbiat Modares UniversityTehranIran Architectural Design Modeling and Fabrication LabDepartment of ArchitectureTarbiat Modares UniversityTehranIran

The present research studies the relationship between place attachment and the perception of form’s visual quality in fifteen outstanding contemporary Iranian architectural cultural *** study puts forward the hypothesis that there is a correlation between the quality of building form and the sense of place attachment,in the sense that creating high visual quality through enhancing the quality of building form increases citizens’initial satisfaction with and subsequent attachment to the *** visual quality influences people’s experience of the environment and improves the quality of *** attachment highlights how people,on a personal level,recreate a sense of place for *** present study adopts the descriptive-analytical method as its theoretical framework and the survey as the empirical *** were developed using the Likert scale and distributed among experts and ordinary *** analysis using SPSS and the adoption of descriptive-analytical statistics,correlation analysis,and regression showed the relationship among the characteristics of *** results show a positive correlation between form and place attachment mediated through visual quality,and they are causal conditions for one *** addition,only some of the buildings under study evoke the same level of place attachment.

关键词： Visual preferences Environmental quality Environmental psychology Mental schemas Contemporary architecture

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Advancing sandstone reservoir compressibility prediction:A correlation-driven methodology

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Petroleum Research 2024年第2期9卷 273-279页

作者： Tarek Ganat Meftah Hrairi amr Badawy Vahid Khosravi Mohammed Abdalla Department of Petroleum Chemical Engineering Sultan Qaboos UniversityP.O.Box 50Al-Khod123MuscatOman Department of Mechanical and Aerospace Engineering International Islamic University MalaysiaP.O.Box 1050728Kuala LumpurMalaysia Reservoir Engineering Section Petronas Carigali SDN BHDP.O.Box 10500088Kuala LumpurMalaysia Department of Chemical and Petroleum Engineering Faculty of EngineeringTechnologyand Built EnvironmentUCSI University56000Kuala LumpurMalaysia Chemical&Petroleum Engineering United Arab Emirates UniversityP.O.Box No.15551Al AinUAE

This study presents a correlation-based approach for predicting the compressibility of sandstone reservoir *** study proposes a matrix of new empirical equations that significantly improve the precision of measuring the pore volume compressibility,with the most optimal fit of results based on a cubic polynomial *** accuracy of the calculations was validated through comparison with actual data using root mean square method,and the suggested correlations significantly enhance the precise prediction of rock compressibility in sandstone *** this study,the source of data collection is consolidated and unconsolidated sandstone from East Asia offshore ***,variations in compressibility with net overburden pressure over the course of the field's lifespan have been *** results demonstrate the application of regression analysis in establishing a network of linkages between independent and dependent *** proposed correlations for consolidated and unconsolidated sandstones offer a remarkable improvement in the accurate calculation of rock compressibility compared to traditional laboratory procedures,with an average error of 2.5%compared to 5-10%for laboratory *** approach of this study offers a cost-effective and time-efficient alternative to remarkedly enhance the overall performance of sandstone reservoirs in the oil and gas industry.

关键词： Compressibility Consolidated and unconsolidated sandstone Rock properties Rock mechanics

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Use of GIS and BIM for the integration of tunnel designand construction process in conventional tunneling

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Underground Space 2024年第3期16卷 261-278页

作者： mansour Hedayatzadeh Jamal Rostami Vasilis Sarhosis Mojtaba Nematollahi Nabiollah Hajiantilaki Abouzar Shafiepour University of Leeds Leeds LS29JTUK Colorado School of Mines GoldenCO 80401USA University of Minho Guimaraes 4800-058Portugal General Mechanic Company Tehran ***Iran Ettehadrah Consulting Engineers Tehran Q83GVWVIran

This paper presents the development of a framework for the parametric design of tunnels using geographic information system (GIS)mapping and building information modelling (BIM). According to the framework, a parametric representation of each system component (e.g., layers of rock mass, size of excavation, topography, fault geometry, primary lining, secondary lining, rock bolts, etc.) can beincorporated in the GIS model with high levels of detail and used for the automatic generation of numerical models for the design oftunnel construction. This parametric evaluation allows the designer to consider several levels of detail for each component, for the effi-cient design and process optimization in conventional tunneling. Information between parametric analysis and numerical simulations canbe freely exchanged with significantly reduced computational effort while results can be exported into BIM. It is anticipated that the proposed framework could lead to a comprehensive, yet efficient analysis of complex conventional tunneling project using parametric evaluations at the early design stages.

关键词： Geographic information system Building information modelling Conventional tunneling Numerical simulations Parametric analysis

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Use of ketamine for severe asthma exacerbation in a pregnant patient with persistent bronchospasm:a case report

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

作者： Melanie Johnson Malak Abbas Jaber Abdo mansour mansour Jessica Jones Pharmacy Department Beaumont HealthDearbornMIUSA Emergency Center Beaumont HealthDearbornMIUSA

Background:Estimated 4%-8%of pregnancies are complicated by *** management in this population is critical to minimize *** presenting with asthma exacerbation are typically managed with standard bronchodilators and systemic ***,additional agents may be used in patients with refractory asthma *** has been used in refractory bronchospasm,although its efficacy in published literature is *** Presentation:We present a case of a pregnant patient with severe asthma exacerbation refractory to standard and salvage treatment who achieved termination of bronchospasm with ketamine ***:After receiving ketamine infusion for several days,the patient had improved air flow and achieved successful extubation,without experiencing rebound *** this individual clinical case alone cannot change guidelines or directives to use in refractory asthma exacerbations,it offers a possible treatment option to patients and providers in unusually severe cases with extenuating risk factors.

关键词： Asthma Bronchospasms Case Report Ketamine Pregnancy

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