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New Antenna Array Beamforming Techniques Based on hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa M.Amer Ashraf A.M.Khalaf amr h.hussein Salman A.Alqahtani Mostafa h.Dahshan hossam M.Kassem Electronics and Communications Engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer Engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the element’s excitations while the GA optimizes the element *** M elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2M−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths M,M−1,andM,*** the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(hPBW).While the middle excitations give the same hPBWas the original LAA with a relatively higher *** the increased hPBWof the odd and even excitations,the element spacing is optimized using the ***,the synthesized arrays have the same hPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider hPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(hPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

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Seismic Analysis of Reinforced Concrete Silos under Far-Field and Near-Fault Earthquakes

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Structural Durability & health Monitoring 2022年第3期16卷 213-233页

作者： Anwer h.hussein hussam K.Risan Department of Civil Engineering Al-Nahrain UniversityBaghdad10072Iraq

Silos are strategical structures used to stockpile various types of granular *** are highly vulnerable to earthquake excitation and have been frequently reported to fail at a higher rate than any other industrial *** seismic response of silos within the near-fault region will suffer a complex combination of loadings due to the unique characteristics of the near-fault ground motions;which are usually associated with a large amplitude pulse at the beginning of either the velocity or the displacement time *** study aims to numerically evaluate the seismic response of reinforced concrete cylindrical silos under near-fault ground motions(NFGM)and far-field ground motions(FFGM).The assessment investigates the impact of the slenderness ratio and the para-meters’influence on the seismic behavior of reinforced concrete *** validity of the Eurocode provisions in the structural safety of silos will also be *** nonlinear time history analysis is carried out through the finite element approach by examining four silos with different slenderness *** concrete damage plas-ticity model is assigned to the silo wall to simulate the nonlinear behavior of concrete in the plastic zone;while,the behavior of the stored material is represented by the Drucker-Prager plastic *** wall-granular material interaction is considered and defined by coulomb’s friction *** results of the near-fault records reveal a growth up to 72.8%in the hoop stress and 160.4%in the vertical stress compared to the far-field ***,the seismic response of reinforced concrete silos is highly sensitive to the type of ground motion,and slender silos tend to impose greater structural demand under the ***,The Eurocode-8 seismic provisions were adequate in the conventional far-field ground motions and less effective in the near-fault zone.

关键词： Silos seismic analysis near-fault earthquake far-field earthquake

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Survey and Analysis of VoIP Frame Aggregation Methods over A-MSDU IEEE 802.11n Wireless Networks

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Computers, Materials & Continua 2021年第2期66卷 1283-1300页

作者： Mosleh M.Abualhaj Abdelrahman h.hussein Manjur Kolhar Mwaffaq Abu Alhija Al-Ahliyya Amman University AmmanJordan Prince Sattam Bin Abdulaziz University Al-KharjSaudi Arabi

The IEEE 802.11n standard has provided prominent features that greatly contribute to ubiquitous wireless *** the last ten years,voice over IP(VoIP)has become widespread around the globe owing to its low-cost or even free call *** combination of these technologies(VoIP and wireless)has become desirable and inevitable for ***,VoIP faces a bandwidth utilization issue when working with 802.11 wireless *** bandwidth utilization is inefficient on the grounds that(i)80 bytes of 802.11/RTP/UDP/IP header is appended to 10–730 bytes of VoIP payload and(ii)765μs waiting intervals follow each 802.11 VoIP *** considering the quality requirements of a VoIP call,be including frame aggregation in the IEEE 802.11n standard has been suggested as a solution for the bandwidth utilization ***,several aggregation methods have been proposed to handle the quality requirements of VoIP calls when carried over an IEEE 802.11n wireless *** this survey,we analyze the existing aggregation methods of VoIP over the A-MSDU IEEE 802.11n wireless *** survey provides researchers with a detailed analysis of the bandwidth utilization issue concerning the A-MSDU 802.11n standard,discussion of the main approaches of frame aggregation methods and existing aggregation methods,elaboration of the impact of frame aggregation methods on network performance and VoIP call quality,and suggestion of new areas to be investigated in conjunction with frame *** survey contributes by offering guidelines to design an appropriate,reliable,and robust aggregation method of VoIP over 802.11n standard.

关键词： VoIP VoIP frame aggregation IEEE 802.11n bandwidth utilization A-MSDU A-MPDU

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Field validation of UhPC layer in negative moment region of steel-concrete composite continuous girder bridge

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 744-761页

作者： Minghong QIU Xudong ShAO Weiye hU Yanping ZhU husam h.hussein Yaobei hE Qiongwei LIU Key Laboratory for Wind and Bridge Engineering of hunan Province College of Civil EngineeringHunan UniversityChangsha 410082China Zhejiang Provincial Institute of Communications Planning Design and Research Co.Ltd.Hangzhou 310013China Department of Civil Architectural and Environmental EngineeringMissouri University of Science and TechnologyRollaMO 65401USA Department of Civil Engineering Ohio UniversityAthensOH 45701-2979USA

Improving the cracking resistance of steel-normal concrete(NC)composite beams in the negative moment region is one of the main tasks in designing continuous composite beam(CCB)bridges due to the low tensile strength of the NC deck at pier *** study proposed an innovative structural configuration for the negative bending moment region in a steel-concrete CCB bridge with the aid of ultrahigh performance concrete(UhPC)*** order to investigate the feasibility and effectiveness of this new UhPC jointed structure in the negative bending moment region,field load testing was conducted on a newly built full-scale *** newly designed structural configuration was described in detail regarding the structural characteristics(cracking resistance,economy,durability,and constructability).In the field investigation,strains on the surface of the concrete bridge deck,rebar,and steel beam in the negative bending moment region,as well as mid-span deflection,were measured under different load ***,a finite element model for the four-span superstructure of the full-scale bridge was established and validated by the field test *** simulated results in terms of strains and mid-span deflection showed moderate consistency with the test *** field test and the finite element model results demonstrated that the new configuration with the UhPC layer provided an effective alternative for the negative bending moment region of the composite beam.

关键词： field test steel-concrete composite beam continuous girder bridge negative bending moment region ultrahigh performance concrete

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Down to Zero Size of VoIP Packet Payload

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Computers, Materials & Continua 2021年第7期68卷 1271-1283页

作者： Mosleh M.Abualhaj Qusai Y.Shambour Abdelrahman h.hussein Qasem M.Kharma Faculty of Information Technology Al-Ahliyya Amman UniversityAmmanJordan

Voice over Internet Protocol(VoIP)is widely used by companies,schools,universities,and other ***,VoIP faces many issues that slow down its *** important issue is poor utilization of the VoIP service network bandwidth,which results from the large header of the VoIP *** objective of this study is to handle this poor utilization of the network ***,this study proposes a novel method to address this large header overhead *** proposed method is called zero size payload(ZSP),which aims to reemploy and use the header information(fields)of the VoIP packet that is dispensable to the VoIP service,particularly the unicast IP voice *** general,these fields are used to carry the VoIP packet ***,the size of the payload is reduced to save *** performance estimation results of the proposed ZSP method showed a considerable improvement in the bandwidth utilization of the VoIP *** example,the saved bandwidth in the tested scenario with the G.723.1,G.729,and LPC codecs reached 32%,28%,and 26%respectively.

关键词： Voice over internet protocol VoIP protocols bandwidth utilization

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Multi-indicator Active Queue Management Method

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Computer Systems Science & Engineering 2021年第8期38卷 251-263页

作者： Mosleh M.Abualhaj Abdelrahman h.hussein Qasem M.Kharma Qusai Y.Shambour Faculty of Information Al-Ahliyya Amman UniversityAmman19328Jordan

A considerable number of applications are running over IP *** increased the contention on the network resource,which ultimately results in *** queue management(AQM)aims to reduce the serious consequences of network congestion in the router buffer and its negative effects on network *** methods implement different techniques in accordance with congestion indicators,such as queue length and average queue *** performance of the network is evaluated using delay,loss,and *** gap between congestion indicators and network performance measurements leads to the decline in network *** this study,delay and loss predictions are used as congestion indicators in a novel stochastic approach for *** proposed method estimates the congestion in the router buffer and then uses the indicators to calculate the dropping probability,which is responsible for managing the router *** experimental results,based on two sets of experiments,have shown that the proposed method outperformed the existing benchmark algorithms including RED,ERED and BLUE *** instance,in the first experiment,the proposed method resides in the third-place in terms of delay when compared to the benchmark *** addition,the proposed method outperformed the benchmark algorithms in terms of packet loss,packet dropping,and packet ***,the proposed method outperformed the benchmark algorithms because it preserves packet loss while maintaining reasonable queuing delay.

关键词： Congestion control network performance active queue management

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Effective hybrid Content-Based Collaborative Filtering Approach for Requirements Engineering

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Computer Systems Science & Engineering 2022年第1期40卷 113-125页

作者： Qusai Y.Shambour Abdelrahman h.hussein Qasem M.Kharma Mosleh M.Abualhaj Faculty of Information Technology Al-Ahliyya Amman UniversityAmman19328Jordan

Requirements engineering(RE)is among the most valuable and critical processes in software *** quality of this process significantly affects the success of a software *** important step in RE is requirements elicitation,which involves collecting project-related requirements from different *** of reusable requirements are typically important sources of an increasing number of reusable software ***,the process of searching such repositories to collect valuable project-related requirements is time-consuming and difficult to perform *** systems have been widely recognized as an effective solution to such ***,this study proposes an effective hybrid content-based collaborative filtering recommendation *** proposed approach will support project stake-holders in mitigating the risk of missing requirements during requirements elicitation by identifying related requirements from software requirement *** experimental results on the RALIC dataset demonstrate that the proposed approach considerably outperforms baseline collaborative filtering-based recom-mendation methods in terms of prediction accuracy and coverage in addition to mitigating the data sparsity and cold-start item problems.

关键词： Requirements engineering recommender systems requirements elicitation collaborative filtering content-based filtering

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Designing terraces for the rainfed farming region in Iraq using the RUSLE and hydraulic principles

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International Soil and Water Conservation Research 2016年第1期4卷 39-44页

作者： Mohammad h.hussein Ibrahiem M.Amien Tariq h.Kariem Department of Soil and Water Resources College of AgricultureBabylon UniversityHillaIraq Department of Soil and Water College of AgricultureSalahaddin University-ArbilArbilKurdistanIraq

The rainfed region in Iraq comprises an area of more than 5 million ha of forest,grazing and farmland *** the plains,the region suffers from moderate to severe water erosion due mainly to overgrazing and land *** to population growth and the shortage in water resources,an expansion in land used for agriculture in the region is *** is an option when utilizing sloping land for agricultural production.A terrace design criterion was developed for the region in which terrace spacing was determined using the Revised Universal Soil Loss Equation(RUSLE);terrace channel specifications were determined using conventional hydraulic *** showed that terracing is feasible on rolling and hilly sloping land in the high rainfall zone(seasonal rainfall 4600 mm)where economic crops are grown to offset the high cost of terrace construction and *** the medium and low rainfall zones(seasonal rainfall 400–600 mm and 300–400 mm),terracing for water erosion control is generally not needed on cultivated land less than 10%in slope where wheat and barley crops are normally grown;however,pioneer research projects are needed to assess the feasibility of terraces of the level(detention)type to conserve rain water in these two zones for a more successful rainfed farming venture.

关键词： Terraces Rainfed agriculture USLE/RUSLE Iraq

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Liver tissue engineering using decellularized scaffolds:Current progress,challenges,and opportunities

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Bioactive Materials 2024年第10期40卷 280-305页

作者： Kamal h.hussein Boyukkhanim Ahmadzada Julio Cisneros Correa Ahmer Sultan Silvana Wilken Bruce Amiot Scott L.Nyberg Department of Surgery Mayo ClinicRochesterMNUnited States William J.von Liebig Center for Transplantation and Clinical Regeneration Mayo ClinicRochesterMNUnited States Department of Surgery Anesthesiologyand RadiologyCollege of Veterinary MedicineAssiut UniversityAssiutEgypt

Liver transplantation represents the only definitive treatment for patients with end-stage liver ***,the shortage of liver donors provokes a dramatic gap between available grafts and patients on the waiting *** liver bioengineering,an emerging field of tissue engineering,holds great potential to overcome this *** approach involves two main steps;the first is liver decellularization and the second is *** decellularization aims to remove cellular and nuclear materials from the organ,leaving behind extracellular matrices containing different structural proteins and growth factors while retaining both the vascular and biliary *** involves repopulating the decellularized liver with appropriate cells,theoretically from the recipient patient,to reconstruct the parenchyma,vascular tree,and biliary *** aim of this review is to identify the major advances in decellularization and recellularization strategies and investigate obstacles for the clinical application of bioengineered liver,including immunogenicity of the designed liver extracellular matrices,the need for standardization of scaffold fabrication techniques,selection of suitable cell sources for parenchymal repopulation,vascular,and biliary tree *** vivo transplantation models are also summarized for evaluating the functionality of bioengineered ***,the regulatory measures and future directions for confirming the safety and efficacy of bioengineered liver are also *** these challenges in whole liver bioengineering may offer new solutions to meet the demand for liver transplantation and improve patient outcomes.

关键词： Bioengineered liver Decellularization Recellularization Reendothelialization Biliary reconstruction

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Effects of the concentration and nature of total dissolved solids in drinking water on feed intake,nutrient digestion,energy balance,methane emission,ruminal fermentation,and blood constituents in different breeds of young goats and hair sheep

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Animal Nutrition 2024年第1期16卷 84-95页

作者： Amlan Kumar Patra Luana Paula dos Santos Ribeiro hirut Yirga Adekayode O.Sonibare Ahmed R.Askar Ali h.hussein Ryszard Puchala Arthur Louis Goetsch American Institute for Goat Research Langston UniversityLangstonOklahoma73050USA Animal and Poultry Nutrition Department Desert Research CenterEl-MatareyaCairo11753Egypt Agriculture Food and Natural ResourcesEastern New Mexico UniversityPortalesNew Mexico88130USA

Understanding how different livestock species and breeds respond to consumption of brackish water could improve usage of this ***,Angora,Boer,and Spanish goat doelings and Dorper,Katahdin,and *** ewe lambs(6 animals per animal type[AT];initial age=296±2.1 days)consuming water with varying concentrations of minerals of a natural brackish water source(BR)and sodium chloride(NaCl;SL)were used to determine effects on water and feed intake,nutrient digestion,heat energy,methane emission,ruminal fluid conditions,and blood constituent *** were 6 simultaneous 6(water treatments[WT])×6(AT)Latin squares with 3-wk *** WT were fresh(FR),BR alone(100-BR),a similar total dissolved solids(TDS)concentration as 100-BR via NaCl addition to FR(100-SL),BR with concentrations of all minerals increased by approximately 50%(150-BR),a similar TDS level as 150-BR by NaCl addition to FR(150-SL),and a similar 150 TDS level achieved by addition of a 1:1 mixture of BR minerals and NaCl to 100-BR(150-BR/SL).Concentrations(mg/kg)in BR were 4928 TDS,85.9 bicarbonate,224.9 calcium,1175 chloride,60.5 magnesium,4.59 potassium,1387sodium,1962 sulfate,and 8.3 boron,and TDS in other WT were 209,5684,7508,8309,and 7319 mg/kg for FR,100-SL,150-BR,150-SL,and 150-BR/SL,*** were very few significant effects of WT or AT×WT interactions,although AT had numerous *** intake was affected by AT(P=0.02)and WT(P=0.04),with greater water intake for 150-SL than for FR,100-BR,100-SL,and *** matter intake among AT was lowest(Pheat energy differed among AT(Phane emission were similar among *** aldosterone concentration was higher(Phan for other *** conclusion,all AT seemed resilient to these WT regardless of mineral source and concentrations,with TDS less than 8300 mg/kg,which did not influence nutrient u

关键词： Goats hair sheep Nutrient utilization Ruminal fermentation Salinity Water quality

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