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A Novel Broadband Antenna Design for 5G Applications

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Computers, Materials & Continua 2021年第4期67卷 1121-1136页

作者： omar A.Saraereh Deparment of Electrical Engineering Engineering FacultyThe Hashemite UniversityZarqa13133Jordan

Wireless communication is one of the rapidly-growing elds of the communication *** continuous growth motivates the antenna community to design new radiating structures to meet the needs of the *** 5G wireless communication has received a lot of attention from both academia and industry and signicant efforts have been made to improve different aspects,such as data rate,latency,mobility,reliability and *** design has received renewed attention in the last decade due to its potential applications in 5G,IoT,mmWave,and massive *** paper proposes a novel design of broadband antenna for 5G mmWave and optical communication *** is a hybrid structure that works for both spectrums and contains an absorption dielectric material with an electrical large size.A hybrid transmission line theory ray-tracing technique is proposed efcient and rapid simulation and optimization of the proposed antenna *** operating frequency and wavelength of the proposed antenna are 28 GHz in the mmWave band and 1550 nm for the optical *** spatial frequency is 30 lp/mm when the contrast transfer function is reduced to 0.7 for the optical *** effective focal length and aperture are 816.86 and 200 *** half-power beamwidth is 3.29◦and the gain is 32.97 dBi for the mmWave *** results show that the proposed hybrid antenna can effectively be deployed simultaneously for both optical and mmWave 5G communication networks.

关键词： Antenna mmwave broadband composite waveguide wireless communicat

Conservation of challenging endemic plant species at high risk of extinction in arid mountain ecosystems:a case study of Rosa arabica Cré*** Egypt

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Journal of Mountain Science 2021年第10期18卷 2698-2721页

作者： Karim omar Ibrahim ELGAMAL Nature Conservation Sector Ministry of EnvironmentCairo 11728Egypt United Nation Development Program(UNDP) Cairo 2007Egypt

Rosa arabica Cré*** a perennial shrub belonging to the family *** is endemic to the high mountain area of *** Protected Area(SCPA)in southern Sinai,Egypt,and is listed as one of the most 100 threatened plants in the ***,it has been listed as critically endangered by IUCN Red List due to its small extent of occurrence and tiny population *** reported the continuous decline in habitat quality for this species and the urgent need to carry out on-ground conservation ***,this research aims to conserve Rosa arabica through in situ practices by implementing the following steps,respectively:a)evaluate the current conservation status through IUCN Red List to extract the environmental factors controlling the species’distribution necessary for establishing the recovery program,b)determine the potential species habitat suitability under the current climate conditions using Maxent,and c)based on the previous two steps,the translocation process for *** in the suitable habitat will be done after the simple layering process as one of the most effective traditional vegetative methods for wild cultivation for this *** steps aimed to reduce the impact of threats and the risk of extinction through increasing the population size,the Extent of Occurrence(EOO),and the Area of Occupancy(AOO).We extracted the environmental factors controlling the target species’distribution and habitat suitability range using the IUCN Red List assessment and Species Distribution Model(SDM).The most suitable habitat for *** is predicted in the middle northern parts of SCPA,with the highest suitability in the High *** of driest quarter,precipitation of wettest month,precipitation of coldest quarter,and aspect are the highest mean contributors determining the distribution of *** in *** arabica potential distribution covers 324.4 km^(2)(7.46%)of the total SCPA area(4350 km^(2)).This area is divided into:18.1 km^(2)high

关键词： Mountain ecosystems Recovery Translocations Layering Conservation Species distribution modelling Maxent IUCN Red List

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

A review on catalytic & non-catalytic bio-oil upgrading in supercritical fluids

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 4-17页

作者： Sainab omar Yang Yang Jiawei Wang Chemical Engineering and Applied Chemistry Aston UniversityBirminghamB47ETUK

This review article summarizes the key published research on the topic of bio-oil upgrading using catalytic and non-catalytic supercritical fluid(SCF)*** precious metal catalysts Pd,Ru and Pt on various supports are frequently chosen for catalytic bio-oil upgrading in *** is reportedly due to their favourable catalytic activity during the process including hydrotreating,hydrocracking,and esterification,which leads to improvements in liquid yield,heating value,and pH of the upgraded *** to the costs associated with precious metal catalysts,some researchers have opted for non-precious metal catalysts such as acidic HZSM-5 which can promote esterification in supercritical *** the other hand,SCFs have been effectively used to upgrade crude bio-oil without a *** methanol,ethanol,and water are most commonly used and demonstrate catalyst like activities such as facilitating esterification reactions and reducing solid yield by alcoholysis and hydrolysis,respectively.

关键词： bio-oil upgrading supercritical review

A Reliable and Scalable Internet of Military Things Architecture

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Computers, Materials & Continua 2021年第6期67卷 3887-3906页

作者： omar Said Amr Tolba Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer Science Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Department of Mathematics and Computer Science Faculty of ScienceMenoufia UniversityShebin Elkoum32511Egypt

Recently,Internet of Things(IoT)technology has provided logistics services to many disciplines such as agriculture,industry,and ***,it has become one of the most important scientific research *** IoT to military domain has many challenges such as fault tolerance and *** this paper,IoT technology is applied on the military field to create an Internet of Military Things(IoMT)***,the architecture of the aforementioned IoMT system is *** architecture consists of four main layers:Communication,information,application,and decision *** layers provided a fault tolerant coverage communication system for IoMT ***,it implemented data reduction methods such as filtering,compression,abstraction,and data prioritization queuing system to guarantee QoS for the transmitted ***,it used decision support technology and IoMT application unification ***,to evaluate the IoMT system,an intensive simulation environment is constructed using the network simulation package,*** simulation results proved that the proposed IoMT system outperformed the traditional military system with regard to the performance metrics,packet loss,end-to-end delay,throughput,energy consumption ratio,and data reduction rate.

关键词： Internet of things internet of military things simulation military battlefield

Treatment of landfill waste, leachate and landfill gas： A review

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Frontiers of Chemical Science and Engineering 2015年第1期9卷 15-32页

作者： Hecham omar Sohrab ROHANI The University of Western Ontario Department of Chemical and Biochemical Engineering London Ontario N6A 5B9 Canada

This review aims at the treatment of the entire landfill, including the waste mass and the harmful emissions： leachate and landfill gas. Different landfill treatments （aerobic, anaerobic and semi-aerobic bioreactor landfills, dry-tomb landfills）, leachate treatments （anaero- bic and aerobic treatments, anammox, adsorption, chemi- cal oxidation, coagulation/flocculation and membrane processes） and landfill gas treatments （flaring, adsorption, absorption, permeation and cryogenic treatments） are reviewed. Available information and the gaps present in current knowledge is summarized. The most significant areas to expand are landfill waste treatments, which in recent years has begun to grow but there is an opportunity for much more. Another area to explore is the treatment of landfill gas, a very large field to which not much effort has been put forth. This review is to compare different treatment methods and give direction to future research.

关键词： landfill aerobic anaerobic leachate landfillgases municipal solid waste

Gastric acid inhibitory and gastric protective effects of cannabis and cannabinoids

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Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 401-408页

作者： omar Abdel-Salam Department of Toxicology and Narcotics Medical Division National Research Centre

Cannabis sativa has long been known for its psychotropic effect. Only recently with the discovery of the cannabinoid receptors, their endogenous legends and the enzymes responsible for their synthesis and degradation, the role of this ‘endocannabinoid system’ in different pathophysiologic processes is beginning to be delineated. There is evidence that CB1 receptor stimulation with synthetic cannabinoids or Cannabis sativa extracts rich in ?9-tetrahydrocannabinol inhibit gastric acid secretion in humans and in experimental animals. This is specially seen when gastric acid secretion is stimulated by pentagastrin, carbachol or 2 deoxy-D-glucose. Cannabis and/or cannabinoids protect the gastric mucosa against noxious challenge with non-steroidal anti-inflammatory drugs, ethanol as well as against stress induced mucosal damage. Cannabis/cannabinoids might protect the gastric mucosa by virtue of its antisecretory, antioxidant, anti-inflammatory, and vasodilator properties.

关键词： Cannabis sativa Gastric mucosa Gastric acid

Outcomes of liver transplantation as an oncologic surgery for different primary liver cancers:A real-world,population-based study

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Hepatobiliary & Pancreatic Diseases International 2023年第1期22卷 88-91页

作者： omar Abdel-Rahman Department of Oncology Cross Cancer Institute and the University of AlbertaEdmontonCanada

To the Editor:Although liver transplantation is likely used to treat individuals with end-stage liver disease because of non-neoplastic reasons,the adoption of liver transplantation in the management of primary liver cancer has been expanding in the past decades[1-3].Prior population-based studies for liver transplantation,in the cancer sphere,focused on delineating the outcomes of patients with hepatocellular carcinoma(HCC)treated with transplantation versus other locoregional treatments[4-6].

关键词： liver cancer surgery

Asian Americans have better outcomes of non-metastatic gastric cancer compared to other United States racial groups: A secondary analysis from a randomized study

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World Journal of Gastrointestinal Oncology 2019年第12期11卷 1151-1160页

作者： omar Abdel-Rahman Department of Oncology University of Alberta and Cross Cancer Institute

BACKGROUND It has been recognized for a long time that gastric cancer behavior and outcomes might be different between patients living in Asian countries vs patients living in Western *** is not clear if these differences would persist between patients of Asian ancestry and patients of other racial subgroups within the multiethnic communities of North *** current study hypothesizes that these differences will present within North American multiethnic *** To evaluate the impact of race on survival outcomes of non-metastatic gastric cancer patients in the United *** This is a secondary analysis of a randomized controlled trial(CALGB 80101 study)that evaluated two adjuvant chemoradiotherapy schedules following resection of non-metastatic gastric ***-Meier analysis and log-rank testing were utilized to explore the overall and disease-free survival differences according to the race of the *** and multivariate Cox regression analyses were then used to explore factors affecting overall and disease-free *** A total of 546 patients were included in the current *** which,73.8%have white race(vs 12.8%black Americans and 8.2% Asian Americans).Using Kaplan-Meier analysis/log-rank testing,Asian Americans appear to have better overall and disease-free survival outcomes compared to other United States racial groups(White Americans,Black Americans,and other racial groups)(P=0.011;P=0.010;respectively).Moreover,in an adjusted multivariate model,Asian American race seems to be associated with better overall and disease-free survival(hazard ratio:0.438;95% confidence interval:0.254-0.754),P=0.003;(hazard ratio:0.460;95% confidence interval:0.280-0.755,P=0.002;respectively).CONCLUSION Asian American patients with non-metastatic gastric cancer have better overall and disease-free survival compared to other racial groups in the United *** preclinical and clinical research is needed to clarif

关键词： Race Asian Americans Survival Prognosis Outcomes