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multi-hazard socio-physical resilience assessment of hurricane-induced hazards on coastal communities

Resilient Cities and Structures 2023年第2期2卷 67-81页

作者： omar m.nofal Kooshan Amini Jamie E.Padgett John W.van de Lindt Nathanael Rosenheim Yousef m.Darestani Amin Enderami Elaina J.Sutley Sara Hamideh Leonardo Duenas-Osorio Florida International University MiamiFLUnited States Rice University HoustonTXUnited States Colorado State University Fort CollinsCOUnited States Texas A&m University College StationTXUnited States michigan Technological University HoughtonMIUnited States The University of Kansas LawrenceKSUnited States Stony Brook Stony Brook UniversityNYUnited States

Hurricane-induced hazards can result in significant damage to the built environment cascading into major impacts to the households,social institutions,and local *** quantifying physical impacts of hurricane-induced hazards is essential for risk analysis,it is necessary but not sufficient for community resilience *** there have been several studies on hurricane risk and recovery assessment at the building-and community-level,few studies have focused on the nexus of coupled physical and social disruptions,particularly when char-acterizing recovery in the face of coastal ***,this study presents an integrated approach to quantify the socio-physical disruption following hurricane-induced multi-hazards(e.g.,wind,storm surge,wave)by considering the physical damage and functionality of the built environment along with the population dynamics over ***,high-resolution fragility models of buildings,and power and transportation infrastructures capture the combined impacts of hurricane loading on the built *** simulat-ing recovery by tracking infrastructure network performance metrics,such as access to essential facilities,this coupled socio-physical approach affords projection of post-hazard population dislocation and temporal evolution of housing and household recovery constrained by the building and infrastructure *** results reveal the relative importance of multi-hazard consideration in the damage and recovery assessment of communities,along with the role of interdependent socio-physical system modeling when evaluating metrics such as housing recovery or the need for emergency ***,the methodology presented here provides a foundation for resilience-informed decisions for coastal communities.

关键词： Fragility analysis Hurricane damage Probabilistic damage assessment Transportation network Power network Housing recovery population impacts

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Critical assessment of R410A alternatives for mini-split air conditioners in the Egyptian market

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Energy and Built Environment 2024年第3期5卷 426-445页

作者： omar m.Zaki omar Abdelaziz mechanical Power Engineering Department Faculty of EngineeringCairo UniversityGiza 12613Egypt Department of mechanical Engineering The American University in CairoAUC AvenueNew Cairo 11835Egypt

In this study,the potential implementation of three different low-GWP refrigerants(R32,R452B,and R454B)as replacements for R410A was *** study was performed using a simulation tool developed by the authors called RACHP-Lab,which is a vapor compression system simulation tool developed based on physics-based simulation for typical mini-split air *** simulation study was carried out and validated using experimental performance data of 10 different air conditioning units available in the Egyptian *** units included fixed-speed or variable-speed compressors and operated in cooling or heating ***-in replace-ment with the new refrigerants was carried *** R32,the capacity increased between 4.9%and 13%for cooling cases,and 6.3%and 12.4%for heating ***,COP did not improve in all *** R452B and R454B with direct replacement,the capacity nearly remained the same,with an increase of COP between 1.6%and 8.0%.Soft optimization was also conducted on cooling cases where compressor suction superheat,condenser subcooling,and compressor volumetric speed were optimized to maximize COP while maintaining the original capacity of R410A.R32 showed an improvement of COP over R410A between 4.6%and 15.5%,while for R452B and R454B between 2.2%and 13.2%.

关键词： Air conditioner Heat pump Alternative refrigerants Vapor compression cycle modeling

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Thermomechanical treatment of austempered ductile iron

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China Foundry 2007年第4期4卷 304-309页

作者： A.A.nofal H.Nasr El-din m.m.Ibrahim Central metallurgical Research and Development Institute (CMRDI)CairoEgypt

The production of lightweight ferrous castings with increased strength properties became unavoidable facing the serious challenge of lighter aluminum and magnesium castings. The relatively new ferrous casting alloy ADI offers promising strength prospects, and the thermo-mechanical treatment of ductile iron may suggest a new route for production of thin-wall products. This work aims at studying the influence of thermomechanical treatment, either by ausforming just after quenching and before the onset of austempering reaction or by cold rolling after austempering. In the first part of this work, ausforming of ADI up to 25% reduction in height during a rolling operation was found to add a mechanical processing component compared to the conventional ADI heat treatment, thus increasing the rate of ausferrite formation and leading to a much finer and more homogeneous ausferrite product. The kinetics of ausferrite formation was studied using both metallographic as well as XRD-techniques. The effect of ausforming on the strength was quite dramatic （up to 70% and 50% increase in the yield and ultimate strength respectively）. A mechanism involving both a refined microstructural scale and an elevated dislocation density was suggested. Nickel is added to ADI to increase hardenability of thick section castings, while ausforming to higher degrees of deformation is necessary to alleviate the deleterious effect of alloy segregation on ductility. In the second part of this work, the influence of cold rolling （CR） on the mechanical properties and structural characteristics of ADI was investigated. The variation in properties was related to the amount of retained austenite （7~） and its mechanically induced transformation. In the course of tensile deformation of ADI, transformation induced plasticity （TRIP） takes place, indicated by the increase of the instantaneous value of strain-hardening exponent with tensile strain. The amount of retained austenite was found to decrease due to

关键词： ADI ausforming cold-rolling thermomechanical treatment transformation induced plasticity

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Applications of synchrophasor technologies in power systems

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Journal of modern Power Systems and Clean Energy 2019年第2期7卷 211-226页

作者： muhammad Usama USmAN m. omar FARUQUE Department of Electrical and Computer Engineering Center for Advanced Power Systems Florida State University

Synchrophasors are time-synchronized electrical measurements that represent both the magnitude and phase angle of the electrical sinusoids. Synchrophasors are measured by fast time-stamped devices called phasor measurement units(PmUs) to constitute the basis of realtime monitoring and control actions in the electric *** to its enhanced situational awareness capabilities,many applications of PmUs are presented in the literature in the past decades. This paper presents a comprehensive summary of synchrophasor technology, its architecture,optimal placement techniques and its applications in electric power transmission and distribution systems. These applications include wide-area situational awareness and monitoring, state estimation, fault location and protective relaying, islanding detection etc. This review also covers some of the existing challenges in its implementation and its potential applications.

关键词： Phasor measurement unit(PmU) Supervisory control and data acquisition(SCADA) Synchrophasor technology(ST) Power system

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Simple operated multipurpose temperature control cryostat

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 793-796页

作者： ABBAS T.A. omar m.S. Department of Physics College of Science University of SalahaddinArbilIraqi KurdistanIraq

A suitable simple optical cryostat for optical, magneto-optical, electrical and thermo-electrical measurements was designed. It is suitable for use in a magnetic pool gap as narrow as less than 1 cm. Throughout a long period of time, the heat diffusion process of the cryostat can be easily operated at slow increase in sample temperature in a range 1.25 K/min at 200 K that will be reduced gradually to 0.66 K at room temperature. Liquid nitrogen was used to cool down the temperature. During the operation, the change in the measured energy gap of a semiconductor sample and other physical parameters resulting from the change of temperature can be corrected through the temperature coefficient of that parameter at the corresponding temperature. The cryostat was successfully used for all experiments mentioned above to measure the properties of a single crystal of GaP (Gallium Phosphate) semiconductor.

关键词： Optical cryostat Electrical cryostat magneto-optical cryostat

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Effectiveness of biofertilizers foliar application on yield and quality traits of flax(Linum usitatissimum L.)

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Oil Crop Science 2024年第2期9卷 91-101页

作者： Saied El Sayed A.B.Bakry O.A.nofal m.A.Abo Horish Plant Nutrition Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt Field Crops Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt

Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and *** have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein *** factors collectively contribute to the growth and development of ***,this study aims to investigate how three biofertilizers(Algae extract,CmS as a by-product of yeast,and metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil *** field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in *** application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons *** applications of algae extract at a rate of 1.50 mL/L along with CmS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,mn),seed oil content,and protein content in flax seeds during both *** highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/*** can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents.

关键词： Flax Bio fertilizers Seeds yield Nutrient contents Quality

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Secure Inverted Index Based Search over Encrypted Cloud Data with User Access Rights management

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Journal of Computer Science & Technology 2019年第1期34卷 133-154页

作者： Fateh Boucenna omar Nouali Samir Kechid m.Tahar Kechadi Security Division Research Center for Scientific and Technical InformationAlgiers 16028Algeria Laboratory of Research in Artificial Intelligence Department of Computer ScienceUniversity of Sciences and Technology H Suari B oumedieneAlgiers 16111Algeria The Insight Centre Unversity College DublinDublinDO4 VIW8Ireland

Cloud computing is a technology that provides users with a large storage space and an enormous computing ***,the outsourced data are often sensitive and confidential,and hence must be encrypted before being ***,classical search approaches have become obsolete and new approaches that are compatible with encrypted data have become a *** privacy reasons,most of these approaches are based on the vector model which is a time consuming process since the entire index must be loaded and exploited during the search process given that the query vector must be compared with each document *** solve this problem,we propose a new method for constructing a secure inverted index using two key techniques,homomorphic encryption and the dummy documents ***,1)homomorphic encryption generates very large ciphertexts which are thousands of times larger than their corresponding plaintexts,and 2)the dummy documents technique that enhances the index security produces lots of false positives in the search *** proposed approach exploits the advantages of these two techniques by proposing two methods called the compressed table of encrypted scores and the double score ***,we exploit a second secure inverted index in order to manage the users'access rights to the ***,in order to validate our approach,we performed an experimental study using a data collection of one million *** experiments show that our approach is many times faster than any other approach based on the vector model.

关键词： searchable encryption cloud computing homomorphic encryption attributeqbased encryption inverted index

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Phase modification and dielectric properties of a cullet–paper ash–kaolin clay-based ceramic

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International Journal of minerals,metallurgy and materials 2018年第3期25卷 350-356页

作者： K.A.Samah m.R.Sahar m.Yusop m.F.omar Advance Optical material Research Group Department of Physics Faculty of Science Universiti Teknologi Malaysia

Novel ceramics from waste material made of(x) paper ash–(80-x) cullet–20 kaolin clay(10 wt% ≤ x ≤ 30 wt%) were successfully synthesized using a conventional solid-state reaction technique. Energy-dispersive X-ray analysis confirmed the presence of Si, Ca, Al, and Fe in the waste material for preparing these ceramics. The influence of the cullet content on the phase structures and the dielectric properties of these ceramics were systematically investigated. The impedance spectra were verified in the range from 1 Hz to 10 mHz at room temperature. The phase of the ceramics was found to primarily consist of wollastonite(CaSiO_3), along with minor phases of γ-dicalcium silicate(Ca_2SiO_4) and quartz(SiO_2). The sample with a cullet content of 55 wt% possessed the optimum wollastonite structure and exhibited good dielectric properties. An increase of the cullet content beyond 55 wt% resulted in a structural change from wollastonite to dicalcium silicate, a decrease in dielectric constant, and an increase in dielectric loss. All experimental results suggested that these novel ceramics from waste are applicable for electronic devices.

关键词： ceramics cullet glass paper ash wollastonite structural properties dielectric properties

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Hybrid Sensor Selection Technique for Lifetime Extension of Wireless Sensor Networks

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Computers, materials & Continua 2022年第3期70卷 4965-4985页

作者： Khaled m.Fouad Basma m.Hassan omar m.Salim Information Systems Department Faculty of Computers and Artificial IntelligenceBenha UniversityBenha13518Egypt Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33516Egypt Electrical Engineering Department Benha Faculty of EngineeringBenha UniversityBenha13518Egypt

Energy conservation is a crucial issue to extend the lifetime of wireless sensor networks(WSNs)where the battery capacity and energy sources are very *** energy-saving techniques can help designers overcome this issue by reducing the number of selected sensors that report environmental measurements by eliminating all replicated and unrelated *** paper suggests a Hybrid Sensor Selection(HSS)technique that combines filter-wrappermethod to acquire a rich-informational subset of sensors in a reasonable *** aims to increase the lifetime of WSNs by using the optimal number of *** the same time,HSS maintains the desired level of accuracy and manages sensor failures with the most suitable number of sensors without compromising the *** evaluation of the HSS technique has adopted four experiments by using four different *** experiments show that HSS can extend the WSNs lifetime and increase the accuracy using a sufficient number of sensors without affecting ***,to ensure HSS credibility and reliability,the proposed HSS technique has been compared to other corresponding methodologies and shows its superiority in energy conservation at premium accuracy measures.

关键词： Energy conservation WSNs intelligent techniques sensor selection

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A Dynamic management Scheme for Internet of Things(IoT)Environments:Simulation and Performance Evaluation

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Computer modeling in Engineering & Sciences 2022年第12期133卷 673-695页

作者： omar Said Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

In recent years,the Internet of Things(IoT)technology has been considered one of the most attractive fields for researchers due to its aspirations and implications for society and life as a *** IoT environment contains vast numbers of devices,equipment,and heterogeneous users who generate massive amounts of ***,things’entry into and exit fromIoT systems occur dynamically,changing the topology and content of IoT networks very ***,managing IoT environments is among the most pressing *** paper proposes an adaptive and dynamic scheme for managing IoT environments is *** management scheme depends on the use of previous management methodologies,considering two main *** first factor is network status,which is determined in *** second factor is a management method’s suitability according to its desired *** test the proposed management scheme,a simulation environment is created using *** metrics used to measure the management scheme performance are bandwidth consumption,energy consumption,packet loss,throughput,delay,usage rate of individualmanagement techniques,and *** simulation results prove that the proposed management scheme outperformed the individual 6LowPANSNmP,CoAP,and LWm2m management schemes.

关键词： Internet of Things IoT management IoT simulation SNmP neural networks big data

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