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Novel design of a compact tunable dual band wireless power transfer(TDB-WPT)system for multiple WPT applications

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 616-628页

作者： Hany A.ATALLAH Rasha hussein AHMED Adel B.abdel-RAHMAN Department of Communications and Electronics Faculty of EngineeringSouth Valley UniversityQena 83523Egypt Egypt-Japan University of Science and Technology Alexandria 21934Egypt

In this study we present the design and realization of a tunable dual band wireless power transfer(TDB-WPT)coupled resonator *** frequency response of the tunable band can be controlled using a surface-mounted *** transmitter(Tx)and the receiver(Rx)circuits are *** top layer contains a feed line with an impedance of 50Ω.Two identical half rings defected ground structures(HR-DGSs)are loaded on the bottom using a varactor *** propose a solution for restricted WPT systems working at a single band application according to the operating *** effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were *** validate the simulation results,the proposed TDB-WPT system was fabricated and *** system occupied a space of 40 mm×40 *** can deliver power to the receiver with an average coupling efficiency of 98%at the tuned band from 817 to 1018 MHz and an efficiency of 95%at a fixed band of 1.6 GHz at a significant transmission distance of 22 *** results of the measurements accorded well with those of an equivalent model and the simulation.

关键词： Defected ground structure(DGS) Surface-mounted Tunable dual band wireless power transfer(TDB-WPT) Varactor

多用途新颖紧凑可调谐双频无线电能传输系统设计（英文）

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Frontiers of Information Technology & Electronic Engineering 2024年第4期 616-629页

作者： Hany A.ATALLAH Rasha hussein AHMED Adel B.abdel-RAHMAN 南谷大学工程学院通信与电子学系埃及-日本科技大学

本文设计并实现了一个可调谐双频无线电能传输耦合谐振器系统。可调谐波段的频率响应可以使用表面贴装变容二极管进行控制。发射器和接收器电路是对称的。顶层包含一个阻抗为50Ω的馈线。通过使用变容二极管，两个相同的半环缺陷接地结... 详细信息

本文设计并实现了一个可调谐双频无线电能传输耦合谐振器系统。可调谐波段的频率响应可以使用表面贴装变容二极管进行控制。发射器和接收器电路是对称的。顶层包含一个阻抗为50Ω的馈线。通过使用变容二极管，两个相同的半环缺陷接地结构被加载在底部。针对工作在单频段（基于工作频率）的受限无线电能传输系统，提出一种解决方案。研究了几何形状、方向、相对距离和偏移对耦合系数的影响。为验证仿真结果，制作并测试了所提可调谐双频无线电能传输系统。系统面积为40 mm×40 mm。在有效传输距离为22 mm时，在817～1018 MHz调谐频段，以98%的平均耦合效率向接收器输送电能，在1.6GHz固定频段，效率为95%。测量结果与等效模型的模拟结果吻合较好。

关键词：缺陷接地结构表面贴装可调谐双频无线电能传输变容二极管

Practical approach to linear endoscopic ultrasound examination of the gallbladder

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World Journal of Radiology 2024年第6期16卷 184-195页

作者： hussein Hassan Okasha Eyad Gadour Hassan Atalla Omar AbdAllah abdel-Hameed Reem Ezzat Ahmed Elsayed Alzamzamy Elsayed Ghoneem Rasha Ahmad Matar Zeinab Hassan Bogdan Miutescu Ayman Qawasmi Katarzyna M Pawlak Ahmed Elmeligui Department of Internal Medicine Division of Gastroenterology and HepatologyKasr Al-Aini School of MedicineCairo UniversityCairo 11562Egypt Department of Gastroenterology and Hepatology King Abdulaziz Hospital-National GuardAhsa 31982Saudi Arabia Department of Medicine School of MedicineZamzam University CollegeKhartoum 11113Sudan Department of Internal Medicine Hepatology and Gastroenterology UnitFaculty of MedicineMansoura UniversityMansoura 35516Egypt Department of Internal Medicine Faculty of MedicineAssiut UniversityAssiut 71511Egypt Department of Gastroenterology and Heptology Maadi Armed Forces Medical ComplexMilitary Medical AcademyCairo 11728Egypt Department of Gastroenterology and Advance Endoscopy Sultant Qaboos Comprehensive Cancer Care and Research CentreMuscat 0961Oman Department of Internal Medicine Stockport Hospitals NHS Foundation TrustManchester SK27JEUnited Kingdom Department of Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 300041Romania Advanced Regional Research Centre in Gastroenterology and Hepatology Victor Babes University of Medicine and PharmacyTimisoara 30041Romania Department of Gastroenterology Al-Makassed Islamic Charitable Society HospitalCairo 11124Egypt Division of Gastroenterology St.Michael’s HospitalUniversity of TorontoToronto M5B 1W8Canada Department of Gastroenterology Southend University HospitalEssex SS26XTUnited Kingdom

The gallbladder(GB)is a susceptible organ,prone to various pathologies that can be identified using different imaging *** ultrasound(TUS)is typically the initial diagnostic method due to its numerous well-established ***,in cases of uncertainty or when a definitive diagnosis cannot be established,computed tomography(CT)or magnetic resonance imaging may be employed to provide more detailed ***,CT scans may sometimes offer inadequate spatial resolution,which can limit the differentiation of GB lesions,particularly when smaller yet clinically relevant abnormalities are ***,endoscopic ultrasound(EUS)provides higher frequency compared to TUS,superior spatial resolution,and the option for contrast-enhanced harmonic imaging,enabling a more comprehensive ***,EUS can serve as a supplementary tool when conventional imaging methods are *** review will describe the standard EUS examination of the GB,focusing on its endosonographic characteristics in various GB path-ologies.

关键词： Endoscopic ultrasound Linear endoscopic ultrasound Gallbladder anatomy Gallbladder pathologies Therapeutic endoscopic ultrasound

Modeling discrete-time analytical models based on random early detection: Exponential and linear

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第3期6卷 85-106页

作者： hussein abdel-Jaber Fadi Thabtah Mike Woodward Department of Information Technology and Computing Faculty of Computer Studies Arab Open University Kingdom of Saudi Arabia Ebusiness Department Canadian University of DubaiUAE Department of Computing University of Bradford Bradford BD71DPUK

Congestion control is among primary topics in computer network in which random early detection(RED)method is one of its common ***,RED suffers from drawbacks in particular when its“average queue length”is set below the buffer’s“minimum threshold”position which makes the router buffer quickly *** deal with this issue,this paper proposes two discrete-time queue analytical models that aim to utilize an instant queue length parameter as a congestion *** assigns mean queue length(mql)and average queueing delay smaller values than those for RED and eventually reduces buffers overflow.A comparison between RED and the proposed analytical models was conducted to identify the model that offers better *** proposed models outperform the classic RED in regards to mql and average queueing delay measures when congestion *** work also compares one of the proposed models(RED-Linear)with another analytical model named threshold-based linear reduction of arrival rate(TLRAR).The results of the mql,average queueing delay and the probability of packet loss for TLRAR are deteriorated when heavy congestion occurs,whereas,the results of our RED-Linear were not impacted and this shows superiority of our model.

关键词： Analytical modeling congestion control discrete-time queues performance measures simulation

On the Relationship between Climatic Variables and Pressure Systems over Saudi Arabia in the Winter Season

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Advances in Atmospheric Sciences 2015年第5期32卷 690-703页

作者： H.M.HASANEAN H.abdel BASSET M.A.A.hussein Department of Meteorology Faculty of Meteorology Environment and Arid Land AgricultureKing Abdulaziz University Department of Meteorology and Astronomy Faculty of Science Al-Azhar University

The synoptic circulation over Saudi Arabia is complicated and frequently governed by the effect of large-scale pressure systems. In this work, we used NCEP–NCAR global data to illustrate the relationship between climatic variables and the main pressure systems that affect the weather and climate of Saudi Arabia, and also to investigate the influence of these pressure systems on surface air temperature（SAT） and rainfall over the region in the winter season. It was found that there are two primary patterns of pressure that influence the weather and climate of Saudi Arabia. The first occurs in cases of a strengthening Subtropical High（Sub H）, a weakening Siberian High（Sib H）, a deepening of the Icelandic Low（Ice L）, or a weakening of the Sudanese Low（Sud L）. During this pattern, the Sub H combines with the Sib H and an obvious increase of sea level pressure（SLP） occurs over southern European, the Mediterranean, North Africa, and the Middle East. This belt of high pressure prevents interaction between midlatitude and extratropical systems, which leads to a decrease in the SAT,relative humidity（RH） and rainfall over Saudi Arabia. The second pattern occurs in association with a weakening of the Sub H, a strengthening of the Sib H, a weakening of the Ice L, or a deepening of the Sud L. The pattern arising in this case leads to an interaction between two different air masses： the first（cold moist） air mass is associated with the Mediterranean depression travelling from west to east, while the second（warm moist） air mass is associated with the northward oscillation of the Sud L and its inverted V-shape trough. The interaction between these two air masses increases the SAT, RH and the probability of rainfall over Saudi Arabia, especially over the northwest and northeast regions.

关键词： climatic variables pressure system surface air temperature rainfall relative humidity Saudi Arabia

Antifouling evaluation of extracts from Red Sea soft corals against primary biofilm and biofouling

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Asian Pacific Journal of Tropical Biomedicine 2017年第11期7卷 991-997页

作者： Yosry abdel Aziz Soliman Ahmed Mohammed Brahim Ahmed hussein Moustafa Mohamed abdel Fattah Hamed Marine Chemistry Lab. Marine Environment DivisionNational Institute of Oceanography and FisheriesSuezEgypt Department of Chemistry Faculty of ScienceZagazig UniversityZagazigEgypt

Objectives: To evaluate antifouling property of extracts from Red Sea soft corals against primary biofilm and ***: Seven species of soft corals Sarcophyton glaucum(a), Sinularia compressa,Sinularia cruciata(a), Heteroxenia fuscescens(a), Sarcophyton glaucum(b), Heteroxenia fuscescens(b) and Sinularia cruciata(b) were chosen to test their extracts as antibacterial and antifouling agents in Eastern Harbour of Alexandria, Mediterranean *** compounds of soft corals were extracted by using methanol and concentrated under vacuum. The residues of extracts were mixed in formulation of inert paint which consisted of rosin, chlorinated rubber and ferrous oxide against micro and macro fouling organisms. The formulated paints were then applied on PVC panels twice by brush,hanged in a steel frame and immersed in Eastern Harbour of Alexandria Mediterranean Sea followed by visual inspection and photographic ***: After 185 days of immersion in seawater, the antifouling results agreed with the antibacterial results where extracts of Sinularia compressa and Heteroxenia fuscescens(b) gave the best activity against marine fouling tubeworms and barnacles. The inhibition activity was correlated with the major functional groups(hydroxyl, amino, carbonyl,aliphatic(fatty acids), C]C of alkene or aromatic rings and CeC l of aryl halides) of the ***: The strong antifouling activity makes them promising candidates for new antifouling additives. After the screening and application of natural organic compounds from soft corals, marine organisms show activity against micro and macro fouling organisms.

关键词： Antibacterial Antifouling Paints Seawater Marine Organisms

Pregnancy outcome of lactating dairy cows assigned for Presynch-Ovsynchsynchronization program and inseminated either at detected standing heat or at scheduled fixed time

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Asian pacific Journal of Reproduction 2019年第4期8卷 181-186页

作者： abdel-Tawab abdel-Razek Yassyn Khalil Mahmoud Mohamed hussein Theriogenology Department Faculty of Veterinary MedicineBeni-Suef UniversityBeni-SuefEgypt

Objective: To determine if insemination at standing heat results in a similar or higher pregnancy rate compared with fixed time artificial insemination, and to study some factors affecting the pregnancy rate. Methods: A total of 8944 inseminations were included in this study, from which 6823 inseminations were done in Holstein cows and 2121 inseminations were performed in Simmental cows. All cows were subjected to a Presynch-Ovsynch protocol. Cows detected in estrus (n=7424) were artificially inseminated, whereas cows not observed in estrus (n=1520) were submitted to fixed time artificial insemination. Results: The overall pregnancy rate of cows inseminated on the basis of the detected standing heat was comparable to that recorded for cows receiving fixed time artificial insemination. A higher pregnancy rate was recorded for cows during cold months than that recorded during hot months (P=0.000). A higher pregnancy rate was recorded for Simmental compared with that recorded for Holstein cows (P=0.001). Regarding parity, significant differences in the pregnancy rate were detected between primiparous and multiparous cows (P=0.040). In addition, artificial insemination technicians had no sigificant effect on pregnancy rate (P>0.05). Meanwhile, the used artificial insemination sires significantly (P=0.000) impacted the pregnancy rate. Conclusions: Insemination of cows detected in standing heat prior to predetermined fixed time results in similar pregnancy outcome and decreases days to the first service compared with insemination at the scheduled fixed time at the end of the Presynch-Ovsynch synchronization program. The overall pregnancy outcome is not affected by the breeding program, but it is highly impacted by cow's breed, parity, artificial insemination sire and breeding season.

关键词： Dairy cow Presynch Ovsynch Standing heat Fixed time artificial insemination

Optimal Implementation of Photovoltaic and Battery Energy Storage in Distribution Networks

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Computers, Materials & Continua 2021年第11期69卷 1463-1481页

作者： hussein abdel-Mawgoud Salah Kamel Hegazy Rezk Tahir Khurshaid Sang-Bong Rhee Department of Electrical Engineering Faculty of EngineeringAswan University81542 AswanEgypt College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz University11911 Al-KharjSaudi Arabia Electrical Engineering Department Faculty of EngineeringMinia University61517 MiniaEgypt Department of Electrical Engineering Yeungnam UniversityGyeongsan38541Korea

Recently,implementation of Battery Energy Storage(BES)with photovoltaic(PV)array in distribution networks is becoming very popular in overall the *** PV alone in distribution networks generates variable output power during 24-hours as it depends on variable natural *** can be able to generate constant output power during 24-hours by installing BES with ***,this paper presents a new application of a recent metaheuristic algorithm,called Slime Mould Algorithm(SMA),to determine the best size,and location of photovoltaic alone or with battery energy storage in the radial distribution system(RDS).This algorithm is modeled from the behavior of SMA in *** the optimization process,the total active power loss during 24-hours is used as an objective function considering the equality and inequality *** addition,the presented function is based on the probabilistic for PV output and different types of system *** candidate buses for integrating PV and BES in the distribution network are determined by the real power loss sensitivity factor(PLSF).IEEE 69-bus RDS with different types of loads is used as a test *** effectiveness of SMA is validated by comparing its results with those obtained by other well-known optimization algorithms.

关键词： Slime mould algorithm optimization distribution networks renewable energy uncertainty

ANALYTICAL MODELS BASED DISCRETE-TIME QUEUEING FOR THE CONGESTED NETWORK

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第1期3卷 68-89页

作者： MOFLEH AL-DIABAT hussein abdel-JABER FADI THABTAH OSMAN ABOU-RABIA MAHMOUD KISHTA Computer Science Department Al-al-Bayt University Jordan Department of Computer Science The World Islamic Sciences&Education(W.I.S.E.)University Amman Jordan Management Information System Department Philadelphia University AmmanJordan Department of Mathematics and Computer Science Laurentian University Sudbury ONCanada Dean of Academic Research Philadelphia University AmmanJordan

Congestion is one of the well-studied problems in computer networks,which occurs when the request for network resources exceeds the buffer *** active queue management techniques such as BLUE and RED have been proposed in the literature to control congestions in early *** this paper,we propose two discrete-time queueing network analytical models to drop the arrival packets in preliminary stages when the network becomes *** first model is based on Lambda Decreasing and it drops packets from a probability value to another higher value according to the buffer *** the second proposed model drops packets linearly based on the current queue *** compare the performance of both our models with the original BLUE in order to decide which of these methods offers better quality of *** comparison is done in terms of packet dropping probability,average queue length,throughput ratio,average queueing delay,and packet loss rate.

关键词： Analytical models congestion control discrete-time queueing simulation