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Performance Enhancement for Adaptive Beam-Forming Application Based Hybrid PSOGSA Algorithm

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Journal of Electromagnetic Analysis and Applications 2015年第4期7卷 126-133页

作者： Ahmed magdy osama m. EL-Ghandour Hesham F. A. Hamed Department of Electrical Engineering Minia University Minia Egypt Department of Electronics Communications and Computer Engineering Helwan University Cairo Egypt

Recently researchers were interested in hybrid algorithms for optimization problems for several communication systems. In this paper, a novel algorithm based on hybrid PSOGSA technique (combination of Gravitational Search Algorithm and Particle Swarm Optimization) is presented to enhance the performance analysis of beam-forming for smart antennas systems using N elements for Uniform Circular Array (UCA) geometry. Complex excitations (phases) of the array radiation pattern are optimized using hybrid PSOGSA technique for a set of simultaneously incident signals. Our results have shown tremendous improvement over the previous work was done using Uniform Linear Array (ULA) geometry and standard GSA in terms of normalized array factor and computational speed for normalized fitness values.

关键词： Smart Antennas UCA Optimization Techniques Beam-Forming

Wind-induced hydrodynamic changes impact on sediment resuspension for large, shallow Lake Taihu, China

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International Journal of Sediment Research 2019年第3期34卷 205-215页

作者： Abdul Jalil Yiping Li Ke Zhang Xiaomeng Gao Wencai Wang Hafiz osama Sarwar Khan Baozhu Pan Salar Ali Kumud Acharya State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University College of Environment Hohai University Laboratory Base of Eco-hydraulic Engineering in Arid Area Xi'an University of Technology Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Division of Hydrologic Sciences Desert Research Institute

The internal sediment release is a key factor controlling eutrophication processes in large, shallow *** resuspension is associated with the wave and current induced shear stress in large, shallow lakes. The current study investigated the wind field impacts on sediment resuspension from the bottom at meiliang Bay of large, shallow Lake Taihu. The impacts of the wind field on the wave, current, and wave-current combined shear stresses were calculated. The critical wind speed range was 4–6 m/s after which wave and current shear stress started to increase abruptly, and onshore wind directions were found to be mainly responsible for greater shear stress at the bottom of Lake Taihu. A second order polynomial fitting correlation was found between wave(R20.4756) and current(R20.4466) shear stresses with wind speed. Wave shear stress accounted for 92.5% of the total shear stress at meiliang *** critical wave shear stress and critical total shear stress were 0.13 N/m2 for sediment resuspension whereas the current shear stress was 0.019 N/m~2 after which suspended sediment concentrations(SSC)increased abruptly. A second order polynomial fitting correlation was found between wave(R20.739),current(R20.6264), and total shear stress(R20.7394) with SSC concentrations at meiliang Bay of Lake Taihu. The sediment resuspension rate was 120 to 738 g/m~2/d during 4–6 m/s onshore winds while offshore winds contributed Z 200 g/m~2/d. The study results reveal the driving mechanism for understanding the role of the wind field in sediment resuspension while considering wind speed and direction as control parameters to define wave and current shear stresses.

关键词： Shear stress Sediment resuspension Lake Taihu Hydrodynamics Wind field

A review: Challenges and opportunities for artificial intelligence and robotics in the offshore wind sector

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能源与人工智能(英文) 2022年第2期8卷 177-212页

作者： Daniel mitchell Jamie Blanche Sam Harper Theodore Lim Ranjeetkumar Gupta osama Zaki Wenshuo Tang Valentin Robu Simon Watson David Flynn Smart Systems Group Institute of SensorsSignals and SystemsSchool of Engineering and Physical SciencesHeriot-Watt UniversityEdinburghEH144ASUnited Kingdom Centre for mathematics and Computer Science Intelligent and Autonomous Systems GroupCWIAmsterdam1098 XG Netherlands Algorithms Group Faculty of Electrical EngineeringMathematics and Computer Science(EEMCS)Delft University of Technology(TU Delft)Delft2628 XE Netherlands The University of manchester Department of Electrical and Electronic EngineeringOxford RoadManchesterM139PL United Kingdom James Watt School of Engineering University of GlasgowG128QQUnited Kingdom

The UK has set plans to increase offshore wind capacity from 22GW to 154GW by 2030. With such tremendous growth, the sector is now looking to Robotics and Artificial Intelligence (RAI) in order to tackle lifecycle service barriers as to support sustainable and profitable offshore wind energy production. Today, RAI applications are predominately being used to support short term objectives in operation and maintenance. However, moving forward, RAI has the potential to play a critical role throughout the full lifecycle of offshore wind infrastructure, from surveying, planning, design, logistics, operational support, training and decommissioning. This paper presents one of the first systematic reviews of RAI for the offshore renewable energy sector. The state-of-the-art in RAI is analyzed with respect to offshore energy requirements, from both industry and academia, in terms of current and future requirements. Our review also includes a detailed evaluation of investment, regulation and skills development required to support the adoption of RAI. The key trends identified through a detailed analysis of patent and academic publication databases provide insights to barriers such as certification of autonomous platforms for safety compliance and reliability, the need for digital architectures for scalability in autonomous fleets, adaptive mission planning for resilient resident operations and optimization of human machine interaction for trusted partnerships between people and autonomous assistants. Our study concludes with identification of technological priorities and outlines their integration into a new ‘symbiotic digital architecture’ to deliver the future of offshore wind farm lifecycle management.

关键词： Artificial intelligence Autonomous systems Digitalization Offshore renewable energy Offshore wind farms Robotics

Efficient Deep CNN model for COVID-19 Classification

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Computers, materials & Continua 2022年第3期70卷 4373-4391页

作者： Walid El-Shafai Amira A.mahmoud El-Sayed m.El-Rabaie Taha E.Taha osama F.Zahran Adel S.El-Fishawy mohammed Abd-Elnaby Fathi E.Abd El-Samie Department Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh84428Saudi Arabia

Coronavirus(COVID-19)infection was initially acknowledged as a global pandemic in Wuhan in *** Health Organization(WHO)stated that the COVID-19 is an epidemic that causes a 3.4%death *** X-Ray(CXR)and Computerized Tomography(CT)screening of infected persons are essential in diagnosis *** are numerous ways to identify positive COVID-19 *** of the fundamental ways is radiology imaging through CXR,or CT *** comparison of CT and CXR scans revealed that CT scans are more effective in the diagnosis process due to their high ***,automated classification techniques are required to facilitate the diagnosis *** Learning(DL)is an effective tool that can be utilized for detection and classification this type of medical *** deep Convolutional Neural Networks(CNNs)can learn and extract essential features from different medical image *** this paper,a CNN architecture for automated COVID-19 detection from CXR and CT images is *** activation functions as well as three optimizers are tested and compared for this *** proposed architecture is built from scratch and the COVID-19 image datasets are directly fed to train *** performance is tested and investigated on the CT and CXR *** activation functions:Tanh,Sigmoid,and ReLU are compared using a constant learning rate and different batch *** optimizers are studied with different batch sizes and a constant learning ***,a comparison between different combinations of activation functions and optimizers is presented,and the optimal configuration is ***,the main objective is to improve the detection accuracy of COVID-19 from CXR and CT images using DL by employing CNNs to classify medical COVID-19 images in an early *** proposed model achieves a classification accuracy of 91.67%on CXR image dataset,and a classification accuracy of 100%on CT dataset with training times of 58 min and 46 min on CXR an

关键词： COVID-19 image classification CNN DL activation functions optimizers

Performance Analysis on a Dual External Cavity Tunable Laser ECTL Source

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Journal of Electromagnetic Analysis and Applications 2015年第4期7卷 134-139页

作者： Ahmed Fawzy osama m. El-Ghandour Hesham F. A. Hamed Department of Electrical Engineering Minia University Minia Egypt Department of Electronics Communications and Computer Engineering Helwan University Cairo Egypt

This paper presents the diffraction effects on the performance of a dual external cavity tunable laser source, whose external cavities are constructed by micro electro mechanical systems (mEmS). One of the main problems in these structures is the optical diffraction as the emitting surface of the laser diode is usually quite limited in the transverse directions. The emitted beam diffracts rapidly in the air and only a small amount of light is coupled back to the source that usually limits the tuning range of the source. Device characteristics such as tuning range, wavelength shift and sensitivity are evaluated. New expression is used and multiple reflections inside external cavities are considered. The simulation results have shown that single external cavity has limited tuning range. It is shown that multiple reflections have significant effect in our model. To get a better engineering for the dual ECTL dimensions, diffraction effects must be taken into account.

关键词： External Cavity Laser Tunable Laser mEmS Optical Diffraction

Gear Drive mechanism for Continuous Variable Valve Timing of IC Engines

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Engineering（科研） 2013年第3期5卷 245-250页

作者： osama H. m. Ghazal mohamad S. H. Dado mechanical Engineering Department Applied Science Private University Amman Jordan

Continuous variable valve actuating (CVVA) technology provides high potential in achieving high performance, low fuel consumption and pollutant reduction. To get full benefits from (CVVT) various types of mechanisms have been proposed and designed. Some of these mechanisms are in production and have shown significant benefits in improving engine performance. In this investigation a newly designed gear drive mechanism that controls the intake valve opening (IVO) and closing (IVC) angles is studied. The control scheme is based on maximizing the engine brake power (P) and specific fuel consumption (BSFC) at any engine speed by continuously varying the phase between the cam shaft angle and the crank shaft angle. A single-cylinder engine is simulated by the “LOTUS” software to find out the optimum phase angle for maximum power and minimum fuel consumption at a given engine speed. The mechanism is a planetary gear drive designed for precise and continuous control. This mechanism has a simple design and operation conditions which can change the phase angle without limitation.

关键词： mechanism Design Planetary Gear Variable Valve Timing Spark Ignition Engines Performance

October 8, 2005 Pakistan Earthquake： Preliminary observations and report of an international conference

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Episodes 2006年第3期29卷 206-208页

作者： mona Lisa A. B. Kausar Azam A. Khwaja m. qasim Jan Department of Earth Sciences Quaid-1-Azam University Islamabad PAKISTAN Director Geological Survey of Pakistan Islamabad PAKISTAN Dean of Faculty of Natural Sciences Professor of Department of Earth Sciences Quaid-i-Azam University Islamabad PAKISTAN National Professor and Vice Chancellor Quaid-i-Azam University Islamabad PAKISTAN

On October 8, 2005, an earthquake of mw 7.6 shook northern Pakistan at 8：50：38 Am local time. The epicenter was located at 34°29′35″N, 73°37′44″E （USGS）, in Neelum Valley, 19 km northeast of muzaffarabad, the capital town of Pakistan-administered Kashmir. This deadliest of the Himalayan earthquakes took a toll of more than 80,000 of human lives, rendered millions homeless, and caused an estimated damage of US $ 5 billion.

关键词：巴基斯坦地震国际会议震级

New Look on Ureterocolic Diversion with Adjuvant Radiotherapy;SECI (South Egypt Cancer Institute) Experience

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Journal of Cancer Therapy 2018年第11期9卷 898-906页

作者： Badawy m. Ahmed Ebrahim Aboeleuon Ahmed m. Abdel-Rahim osama m. Abd Elbadee Surgical Oncology Department South Egypt Cancer Institute Assiut University Assiut Egypt Urology Unit South Egypt Cancer Institute Assiut University Assiut Egypt Radiotherapy Department South Egypt Cancer Institute Assiut University Assiut Egypt

Background: Ureterosigmoidostomy was the first form of continent urinary diversion and had broad popularity during the first half of the 20th century. Primary enthusiasm was followed by disappointment when serious problems such as pyelonephritis, electrolyte imbalance, renal calculi and renal function deterioration become evident. In the 1950s these life threatening complications led to avoid this urinary diversion in favor of uretro-intestinal conduits. Objectives: Our aim was to evaluate our experience in ureterocolic shunt after radical cystectomy for bladder cancer. methodology: This study was conducted in surgical oncology department, South Egypt cancer institute, Assiut university;in the period from January 2012 to January 2017 and including 115 patients (75 males & 40 females). Results: This is retrospective study including 115 patients (75 males & 40 females). Operative time was 130 minutes ranging between 2 to 2.5 hours. Average blood loss was 450 ml. After removal of rectal tube all patients were continent except 15 patients who were improved after 1 - 3 days. Within a month 12 patients had night incontinence and 5 patients had day time incontinence. After that day and night continence gradually improved in all patients except two females who had persistent night soiling and was in need for night time rectal tube. Conclusion: Ureterosigmoidostomy regains the interest of surgical oncology and urologist because of its simplicity and absence of appliance as many patients refusing cutaneous stoma and others are not suitable for orthotopic substitutes.

关键词： Ureterocolic Shunt Ureterosigmoidostomy Continent Diversion

Lateral Waves near the Surface of Sea

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Journal of Electromagnetic Analysis and Applications 2011年第6期3卷 199-207页

作者： osama m. Abo-Seida Samira T. Bishay Khaled m. El-morabie 不详

In this research, we investigate the propagation of lateral electromagnetic wave near the surface of sea. Interference patterns generated by the superposition of the lateral and direct waves along the sea surface (flat and rough) are shown. The field generated by a vertical magnetic dipole embedded below the sea surface (having a flat and perturbed upper surface) is shown to consist of a lateral-wave and a reflected-wave. Closed-form expressions for the lateral waves near the surface of the sea are obtained and compared with those mentioned for the reflected waves numerically for the con-sidered model.

关键词： Stratified media Rough Surface Radiation In Sea Lateral Waves