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Game Theory-based IoT Efficient Power Control in Cognitive UAV

Computers, Materials & Continua 2022年第7期72卷 1561-1578页

作者： Fadhil Mukhlif Norafida Ithnin omar b.abdulghafoor Faiz Alotaibi Nourah Saad Alotaibi Information Assurance and Security Research Group(IASRG) School of ComputingFaculty of EngineeringUniversiti Teknologi MalaysiaJohorMalaysia Electronic and Telecommunication Department College of EngineeringThe American University of KurdistanIraq Faculty of Computer Science and Information Technology Universiti Putra MalaysiaSelangorMalaysia Computer Department Faculty of Applied CollegeImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia

With the help of network densification,network coverage as well as the throughput can be improved via ultra-dense networks(UDNs).In tandem,Unmanned Aerial Vehicle(UAV)communications have recently garnered much attention because of their high agility as well as widespread *** this paper,a cognitive UAV is proposed for wireless nodes power pertaining to the IoT ground ***,the UAV is included in the IoT system as the source of power for the wireless nodes as well as for resource *** quality of service(QoS)related to the cognitive node was considered as a utility function based on pricing scheme that was modelled as a non-cooperative game theory in order to maximise users’net utility ***,an energy efficiency non-cooperative game theory power allocation with pricing scheme(EE-NGPAP)is proposed to obtain an efficient power control within IoT wireless ***,uniqueness and existence of the Nash equilibrium have been demonstrated mathematically and through *** results show that the proposed energy harvest algorithm demonstrated considerable decrease in transmitted power consumption in terms of average power reduction,which is regarded to be apt with the 5Gnetworks’***,the proposed algorithm requires around 4 iterations only to converge to NE which makes the algorithm more suitable in practical heterogeneous scenarios.

关键词： UAV drones WSN IoT game theory energy efficiency 5G&b5G networks

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VISCOMETRIC INVESTIGATIONS OF POLYVINYLPYRROLIDONE IN MIXED SOLVENTS AND WITH VARYING TEMPERATURE

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Chinese Journal of Polymer Science 2005年第4期23卷 367-371页

作者： omar Melad omar Abu-Tiem Rajai baraka Chemistry Department

The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in *** intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent *** was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in *** viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_*** effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.

关键词： Polyvinylpyrrolidone Intermolecular excluded volume effect Intrinsic viscosity

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Reintegrating nanogranitoid inclusion composition to reconstruct the prograde history of melt-depleted rocks

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Geoscience Frontiers 2019年第2期10卷 517-525页

作者： omar bartoli Department of Geosciences University of Padova

A recent fascinating development in the study of high-grade metamorphic basements is represented by the finding of tiny inclusions of crystallized melt(nanogranitoid inclusions) hosted in peritectic phases of migmatites and granulites. These inclusions have the potential to provide the primary composition of crustal melts at the source. A novel use of the recently-published nanogranitoid compositional database is presented here. Using granulites from the world-renowned Ivrea Zone(NW Italy) on which the original melt-reintegration approach has been previously applied, it is shown that reintegrating melt inclusion compositions from the published database into residual rock compositions can be a further useful method to reconstruct a plausible prograde history of melt-depleted rocks. This reconstruction is fundamental to investigate the tectonothermal history of geological terranes.

关键词： Nanogranitoids Melt-reintegration Granulite High-temperature metamorphism

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Design of a Novel THz Modulator for b5G Communication

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Computers, Materials & Continua 2022年第10期73卷 1055-1066页

作者： omar A.Saraereh Department of Electrical Engineering Faculty of EngineeringThe Hashemite UniversityZarqa13133Jordan

Wireless data traffic has expanded at a rate that reminds us of Moore’s prediction for integrated circuits in recent years,necessitating ongoing attempts to supply wireless systems with ever-larger data rates in the near future,despite the under-deployment of 5G ***(THz)communication has been considered a viable response to communication blackout due to the rapid development of THz technology and *** communication has a high frequency,which allows for better *** is a fast expanding and evolving industry,driven by an increase in wireless traffic volume and data transfer speeds.A THz modulator based on a hybrid metasurface was devised and built in this *** device’s modulation capabilities were modelled and proved *** electrolyte is an ion-gel medium implanted between graphene and metasurface,and the active material is *** the metasurface,the interaction between the THz wave and graphene is ***,an external bias voltage was employed to actively regulate the THz waves by tuning the electrical conductivity of *** results show that with a minimal bias voltage,the device can achieve a modulation depth of up to 73%at the resonant ***,during the modulation process,the resonance frequency remains almost *** a result,the proposed gadget offers a unique tool for substantial THz amplitude modulation at low voltages.

关键词： Terahertz communication modulator metasurface graphene

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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

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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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Central pancreatectomy:a new technique for resection of selected pancreatic tumors

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 93-96页

作者： omar J Shah Irfan Robbani Parvez Nazir Athar b Khan Department of Surgical Gastroenterology Sheri-Kashmir Institute of Medical Sciences Department of Radiodiagnosis/Imaging Sheri-Kashmir Institute of Medical Sciences

bACKGROUND:Pancreatic tumors located in the neck region usually require pancreaticoduodenectomy or *** small benign tumors enucleation is not usually feasible due to their size and localization;then pancreatectomy is often *** pancreatectomy consists of a limited resection of the midportion of the pancreas and can be offered in benign and low-grade malignant tumors of the neck of the *** study aimed to evaluate whether central pancreatectomy has a place in pancreatic surgery. METHODS:In this study,which covered a period of 14 months,we performed central pancreatectomy in four selected *** evaluation and operative frozen section biopsy in indicated cases allowed proper selection for the *** details,complications and follow-up were recorded. RESULTS:Four patients,two with serous cystadenoma,and one with an islet cell tumor,and one with a hydatid cyst, were identified for the *** mean tumor size was 3 cm,the mean operative time was 217.5 minutes,and the mean blood loss was 382.5 *** was no morbidity or mortality in this *** endocrine or exocrine deficiency was observed in any patient during a mean follow-up of 22.7 months. CONCLUSIONS:Central pancreatectomy is a procedure that offers excellent results in benign and low-grade malignant *** preserves functional elements(endocrine and exocrine)of the pancreas and also eliminates the infective and hematological effects of ***,central pancreatectomy should be included in the armamentarium of pancreatic surgery,and in order to obtain good results,proper indications and adequate experience are recommended.

关键词： central pancreatectomy benign pancreatic tumors low-grade malignant tumor

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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

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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

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Finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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Friction 2024年第3期12卷 554-568页

作者： K.Y.Eayal AWWAD Khosro FALLAHNEZHAD b.F.YOUSIF Ahmad MOSTAFA omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for Future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(FEM)and experimental ***’s wear equation was integrated into a developed FORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** FEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

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