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Designing a Protection Scheme in micro-Grid Systems with DG Using Central Protection Unite and multiple Setting Group Protection Relays

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Journal of Power and Energy Engineering 2024年第9期12卷 37-49页

作者： mostafa I. Saleh Gaber el-Saady Ali m. Yousef el-Noby A. Ibrahim Alfanar Company Mecca Saudi Arabia Department of electrical Engineering Faculty of Engineering Asyut University Asyut Egypt

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

关键词： Directional Overcurrent Relay Protection Coordination Distributed Generators Central Protection Unite multiple Setting Group Protection Relay

Hybrid Optimization Algorithm for Handwritten Document Enhancement

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Computers, materials & Continua 2024年第3期78卷 3763-3786页

作者： Shu-Chuan Chu Xiaomeng Yang Li Zhang Václav Snášel Jeng-Shyang Pan College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China School of Information and Control Engineering Qingdao University of TechnologyQingdao266520China Faculty of electrical Engineering and Computer Science VŠB-TU OstravaOstrava70080Czech Republic Department of Information management Chaoyang University of TechnologyTaichung41349Taiwan

The Gannet Optimization Algorithm (GOA) and the Whale Optimization Algorithm (WOA) demonstrate strong performance;however, there remains room for improvement in convergence and practical applications. This study introduces a hybrid optimization algorithm, named the adaptive inertia weight whale optimization algorithm and gannet optimization algorithm (AIWGOA), which addresses challenges in enhancing handwritten documents. The hybrid strategy integrates the strengths of both algorithms, significantly enhancing their capabilities, whereas the adaptive parameter strategy mitigates the need for manual parameter setting. By amalgamating the hybrid strategy and parameter-adaptive approach, the Gannet Optimization Algorithm was refined to yield the AIWGOA. Through a performance analysis of the CEC2013 benchmark, the AIWGOA demonstrates notable advantages across various metrics. Subsequently, an evaluation index was employed to assess the enhanced handwritten documents and images, affirming the superior practical application of the AIWGOA compared with other algorithms.

关键词： metaheuristic algorithm gannet optimization algorithm hybrid algorithm handwritten document enhancement

Processing of Ceramic Based Nanocomposite Usingα-Al_2O_3 Powder and FeCl_2 Solution as Starting materials

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Journal of materials Science & Technology 2007年第6期23卷 837-842页

作者： mohamed m.el-sayed Seleman Department of materials and metallurgical Engineering Faculty of Petroleum and Mining EngineeringPost Code 43721SuezEgypt

Alumina-iron nanocomposite powders were prepared by a two-step process. In the first step, α-Al2O3-FeCl2 powder mixture was formed by mixing α-Al2O3 powders with FeCl2 solution followed by drying. In the second step, the FeCl2 in the dry power mixture was selectively reduced to iron particles. A reduction temperature of 750℃ for 15 min in dry H2 was chosen based on the thermodynamic calculations. The concentration of iron in FeCl2 solution was calculated to be 20 vol. pct in the final composite. Two techniques were used to produce composite bulk materials. The Al2O3 nanocomposite powders were divided to two batches. The first batch of the produced mixture was hot pressed at 1400℃ and 27 mPa for 30 min in a graphite die. To study the effect of oxygen on the Al2O3/Fe interface bonding and mechanical properties of the composite, the second batch was heat treated in air at 700℃ for 20 min to partially oxidize the iron particles before hot pressing. Characterization of the composites was undertaken by conventional density measurements, X-ray diffractometry （XRD）, scanning electron microscopy （SEm）, transmission electron microscopy （TEm） and electron probe micro analysis （EPmA）. The suggested processing route （mixing, reduction and hot pressing） produces ceramic-metal nanocomposite much tougher than the pure Al2O3. The fracture strength of the produced Al2O3/Fe nanocomposite is nearly twice that of the pure Al2O3. The presence of spinel phase, FeAl204, as thick layer around the Fe particles in the Al2O3 matrix has a detrimental effect on interfacial bonding between Fe and AI203 and the fracture properties of the composite.

关键词： Ferrous chloride Reduction Alumina-iron nanocomposite Spinel phase

Phosphoric Acid Pretreatment and Saccharification of Paper Sludge as a Renewable material for Cellulosic Fibers

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Journal of Renewable materials 2024年第9期12卷 1573-1591页

作者： Samar el-mekkawi Wafaa Abou-elseoud Shaimaa Fadel Enas Hassan mohammad Hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green industry. This waste contains valuable sugars that can be converted into important chemicals such as ethanol, poly hydroxybutyrate, and lactic acid. However, the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose, which hinders hydrolysis. To address this, pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and chemicals. The created prediction model using the response surface method considered factors such as acid concentration (ranging from 60% to 85%), consistency (ranging from 4% to 10%), temperature (ranging from 25°C to 80°C), and time (ranging from 0.5 to 4 h). The results revealed that the model’s significant factors affecting the yield were acid concentration, reaction time, temperature, and the product of acid concentration and temperature, while the model’s significant factors affecting the crystallinity were the consistency, the temperature, and their product. The results showed that the optimum conditions for pretreatment were using an acid concentration of 64%, temperature of 25°C, consistency of 10%, and time of 30 min. The hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%, compared to only 18% weight loss in non-pretreated paper sludge. Furthermore, the optimized conditions led to low levels of furfurals and acetic acid, which are undesirable by-products that can interfere with sugar fermentation. The total sugar obtained under the optimized conditions was 0.43 g glucose/g sample (10.46 g/L), while the contents of methyl furfural, furfural, and acetic acid were 21.65, 235.7, and 4.57 mg/L, respectively. This study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge, enabling efficient saccharification and the production of sugars with minimal undesired

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity

Thermodynamic Performance Analysis of Geothermal Power Plant Based on Organic Rankine Cycle (ORC) Using mixture of Pure Working Fluids

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Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul Sattar Laghari mohammad Waqas Chandio Laveet Kumar mamdouh el Haj Assad Department of mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar Sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation Solver(EES).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

Gut microbiota predicts the diagnosis of ulcerative colitis in Saudi children

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World Journal of Clinical Pediatrics 2024年第1期13卷 118-124页

作者： mohammad el mouzan Ahmed Al Sarkhy Asaad Assiri Department of Pediatrics Gastroenterology UnitKing Saud UniversityRiyadh 11461Saudi Arabia

BACKGROUND Ulcerative colitis(UC)is an immune-mediated chronic inflammatory condition with a worldwide *** the etiology of this disease is still unknown,the understanding of the role of the microbiota is becoming increasingly *** To investigate the predictive power of the gut microbiota for the diagnosis of UC in a cohort of newly diagnosed treatment-naïve Saudi children with *** The study population included 20 children with a confirmed diagnosis of UC and 20 healthy *** DNA was extracted and sequenced,and shotgun metagenomic analysis was performed for bacteria and *** and bioinformatics demonstrated significant dysbiosis in the form of reduced alpha diversity,beta diversity,and significant difference of abundance of taxa between children with UC and control *** receiver operating characteristic curve,a probability curve,was used to determine the difference between the UC and control *** area under the curve(AUC)represents the degree of separability between the UC group and the control *** AUC was calculated for all identified bacterial species and for bacterial species identified by the random forest classification algorithm as important potential biomarkers of UC.A similar method of AUC calculation for all bacteriophages and important species was *** The median age and range were 14(0.5-21)and 12.9(6.8-16.3)years for children with UC and controls,respectively,and 40%and 35%were male for children with UC and controls,*** AUC for all identified bacterial species was 89.5%.However,when using the bacterial species identified as important by random forest classification algorithm analysis, the accuracy increased to 97.6%. Similarly, the AUC for all theidentified bacteriophages was 87.4%, but this value increased to 94.5% when the important bacteriophagebiomarkers were *** very high to excellent AUCs of fecal bacterial and viral species sugge

关键词： Ulcerative colitis microbiota Area under the curve Children Saudi Arabia

modelling the monthly hydrological balance using Soil and Water Assessment Tool(SWAT)model:A case study of the Wadi mina upstream watershed

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Journal of Groundwater Science and Engineering 2024年第2期12卷 161-177页

作者： Hanane mebarki Noureddine maref mohammed el-Amine Dris Civil Engineering and Environmental Laboratory(LGCE) University of Djillali LiabèsFaculty of TechnologyHydraulics departmentBen M'Hidi districtP.O.Box 8922000Sidi Bel AbbèsAlgeria.

modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and *** study aims to model the monthly hydrological water cycle in the Wadi mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological *** modelling integrates spatial data such as the Digital elevation model(DEm),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind *** SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December *** and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this *** SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.

关键词： SWAT model Performance Parameters Runoff Groundwater Wadi

modern mobile malware Detection Framework Using machine Learning and Random Forest Algorithm

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Computer Systems Science & Engineering 2024年第5期48卷 1171-1191页

作者： mohammad Ababneh Ayat Al-Droos Ammar el-Hassan School of Computing Sciences Princess Sumaya University for TechnologyAmman11941Jordan

With the high level of proliferation of connected mobile devices,the risk of intrusion becomes *** Intelligence(AI)and machine Learning(mL)algorithms started to feature in protection software and showed effective *** algorithms are nonetheless hindered by the lack of rich datasets and compounded by the appearance of new categories of malware such that the race between attackers’malware,especially with the assistance of Artificial Intelligence tools and protection solutions makes these systems and frameworks lose effectiveness *** this article,we present a framework for mobile malware detection based on a new dataset containing new categories of mobile *** focus on categories of malware that were not tested before by machine Learning algorithms proven effective in malware *** carefully select an optimal number of features,do necessary preprocessing,and then apply machine Learning algorithms to discover malicious code *** our experiments,we have found that the Random Forest algorithm is the best-performing algorithm with such mobile malware with detection rates of around 99%.We compared our results from this work and found that they are aligned well with our previous *** also compared our work with State-of-the-Art works of others and found that the results are very close and competitive.

关键词： Android malware detect prevent artificial intelligence machine learning mobile CICmalDroid2020 CCCSCIC-Andmal-2020

Thermal explosion of a reactive gas mixture at constant pressure for non-uniform and uniform temperature systems

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Defence Technology（防务技术） 2022年第10期18卷 1842-1851页

作者： Saad A.el-sayed mechanical Power Engineering Dept.Zagazig University ZagazigAlshrkiaEgypt

In this study,the approximate and exact solutions for the stationary-state of the solids model with neglecting reactant consumption for both non-uniform and uniform temperature systems were applied on gas ignition under a constant pressure *** criticality conditions for a slab,an infinite cylinder,and a sphere are determined and discussed using dimensionless temperatures under constant ambient and surface temperatures for a non-uniform temperature *** solution for a Semenov model with convection heat loss was also *** solution of the Semenov problem for constant volume or density as a solid and constant pressure were *** critical parameterδis calculated and compared with those of Frank-Kamenetskii solution *** validation of the calculated ignition temperatures with other exact solution and experimental results were *** relation between critical parameters form Semenov and *** solution was introduced.

关键词： Thermal explosion Approximate solution Critical conditions Distributed and uniform temperature systems