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Overall Assessment of Heat Transfer for a Rarefied Flow in a Microchannel with Obstacles Using Lattice Boltzmann Method

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工程与科学中的计算机建模(英文) 2024年第1期138卷 273-299页

作者： Siham Hammid Khatir Naima Omolayo M.Ikumapayi Cheikh Kezrane Abdelkrim Liazid Jihad Asad Mokdad Hayawi Rahman Farhan Lafta Rashid Naseer ali Hussien Younes Menni Laboratory of Development in Mechanics and Materials(LDMM) Zian Achour UniversityDjelfaPB 3117Algeria Department of Technology University Center Salhi Ahmed Naama(Ctr.Univ.Naama)P.O.Box 66Naama45000Algeria Department of Mechanical and Mechatronics Engineering Afe Babalola University Ado Ekiti360101Nigeria Departement of Physics Faculty of ScienceAbou Bekr Belkaid UniversityTlemcen13000Algeria Department of Physics Faculty of Applied SciencesPalestine Technical University-KadoorieTulkarmPalestine Aeronautical Technical Engineering Al-Farahidi UniversityBaghdad10011Iraq Mechanical Engineering Department University of KerbalaKarbala56001Iraq Information and Communication Technology Research Group Scientific Research CenterAl-Ayen UniversityThi-QarIraq National University of Science and Technology Dhi QarIraq

The objective of this investigation is to assess the effect of obstacles on numerical heat transfer and fluid flow momentum in a rectangular microchannel(MC).Two distinct configurations were studied:one without obstacles and the other with alternating obstacles placed on the upper and lower *** research utilized the thermal lattice Boltzmann method(LBM),which solves the energy and momentum equations of fluids with the BGK approximation,implemented in a Python coding *** jump and slip velocity conditions were utilized in the simulation for the MC and extended to all obstacle *** study aims to analyze the rarefaction effect,with Knudsen numbers(Kn)of 0.012,0.02,and *** outcomes indicate that rarefaction has a significant impact on the velocity and temperature *** presence of nine obstacles led to slower fluid movement inside the microchannel MC,resulting in faster cooling at the *** MCs with obstacles,the rarefaction effect plays a crucial role in decreasing the Nusselt number(Nu)and skin friction coefficient(Cf).Furthermore,the study demonstrated that the obstacles played a crucial role in boosting fluid flow and heat transfer in the *** findings suggest that the examined configurations could have potential applications as cooling technologies in micro-electro-mechanical systems and microdevice applications.

关键词： Microfluid rarefied flow LBM microchannel Knudsen number numerical simulation

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Analysis of Factors that Affect Government Digitization:A Pilot Case Study of Pakistan

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Computers, Materials & Continua 2021年第1期66卷 291-301页

作者： Salman ahmed Muhammad ali Khan Department of Computer Systems Engineering University of Engineering&TechnologyPeshawarPakistan

One of the greatest factors that affects the economic condition of a country is its *** the model of good governance,the primary elements for stronger institution include efficiency,transparency,and accountability;and technology plays a major role in improving these ***,there are myriad of challenges when it comes to practical integration of technology in these institutions for *** is more challenging when a country is developing and one that is already weak *** is also important to mention that the challenges of digitization in public sector is not limited to developing countries *** is equally challenging,even today,in already developed countries to digitally transform their public institutions for improved policymaking and for responsive service *** factors contribute to the failure of such digitization initiatives,more so within developing *** the purpose of this paper is to identify those factors,to measure the significance of each of those factors,and to realize and overcome *** research considered the case study of Pakistan;however,the results are very likely to match the conditions of other developing regions around the *** questionnaires and interviews,valuable feedback was gathered from up to 25 senior government officers that are closely associated with digitization initiatives in public *** feedback to the questions were overall *** results indicate the most significant of factors that affect government digitization in this developing region,including some factors that were not expected.

关键词： E-governance government digitization information management sustainability

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Control of Wave Propagation and Effect of Kerr Nonlinearity on Group Index

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Communications in Theoretical Physics 2013年第7期60卷 87-92页

作者： Hazrat ali Ziauddin Iftikhar ahmed Department of Physics University of Malakand Department of Physics COMSATS Institute of Information Technology

We use four-level atomic system and control the wave propagation via forbidden decay rate. The Raman gain process becomes dominant on electromagnetically induced transparency (EIT) medium by increasing the forbidden decay rate via increasing the number of atoms [G.S. Agarwal and T.N. Dey, Phys. Rev. A 74 (2005) 043805 and K. Harada, T. Kanbashi, and M. Mitsunaga, Phys. Rev. A 73 (2006) 013803]. The behavior of wave propagation is dramatically changed from normal (subluminal) to anomalous (superluminal) dispersion by increasing the forbidden decay rate. The system can also give a control over the group velocity of the light propagating through the medium via Kerr field.

关键词： normal and anomalous dispersion Kerr field group index

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Comprehensive evaluation and sensitivity analysis of regeneration energy for acid gas removal plant using single and activated-methyl diethanolamine solvents

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1684-1693页

作者： Ammar ali Abd Samah Zaki Naji ahmed Barifcani Water Resources Engineering College Al-Qasim Green UniversityBabylonIraq Petroleum Engineering Department Kerbala UniversityKerbalaIraq Chemical Engineering Department Curtin University of TechnologyPerthAustralia.

The absorption of acid gas using reactive amines is among the most widely used types of capturing ***,the absorption process requires intensive energy expenditure majorly in the solvent regeneration *** study simultaneously evaluated the regeneration energy of MDEA and PZ/MDEA solvents in terms of heat of absorption,sensible heat,and vaporization *** Hysys version 8.8 simulation tool is applied to model the full acid gas removal plant for the chemical absorption *** new energy balance technique presents around the absorption and desorption columns to bring a new perspective of energy distribution in the capturing of acid gas *** analysis of regeneration energy and its three contributors is performed at several operation parameters such as absorber and stripper pressures,lean amine circulation rate,solvent concentration,reflux ratio,and CO2 and H2 S *** results show that the heat of absorption of PZ/MDEA system is higher than that for MDEA system for the same operating *** sensible heat is the main contributor in the required regeneration energy of MDEA solvent *** simulation results have been validated against data taken from real plant and *** product specifications of our simulation corroborate with real plant data in an excellent approach;additionally,the profile temperature of the absorber and the stripper columns are in good agreement with *** overall results highlight the direction of the effects of each parameter on the heat of absorption,sensible heat,and vaporization heat.

关键词： Heat of absorption Sensible heat Vaporization heat Regeneration energy Acid gases capturing Piperazine Activated-Methyl diethanolamine

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Natural regeneration of Pinus brutia Ten. in a recreational public forest in Zawita-Kurdistan region, Iraq

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Journal of Forestry Research 2019年第5期30卷 1849-1857页

作者： Hassan Muhamed Sami Youssef ahmed Mustafa Hishyer suliman Aree Abdulqader Hishyer Mohammed Richard Michalet Department of Forestry College of AgricultureUniversity of DuhokDuhokKurdistan RegionIraq AMAP(Botany and Modelling of Plant Architecture and Vegetation) University of Montpellier34398 Montpellier Cedex 5France Department of Ecotourism College of AgricultureUniversity of DuhokDuhokKurdistan RegionIraq Directorate of Forestry and Rangelands DuhokKurdistan RegionIraq UMR CNRS 5805 EPOC Universitede BordeauxAllee Geoffroy Saint-Hilaire CS 5002333615 Pessac CedexFrance

Zawita natural forest has recently has been subject to mass recreational activities during spring that have denuded large areas of the *** was thus essential to assess regeneration before designing optimizing *** this end,we studied the overstory canopy and microhabitat conditions for recruitment of Pinus brutia Ten in 10 plots(20×25 m)on the southern aspects where the Zawita natural forest is still *** total,1540 regenerating *** were recorded,854 seedlings,597 saplings,and 89 *** and saplings were more frequent beyond the canopy than under the canopy of the parent *** requirements differed between seedlings and *** probability of the occurrence of seedlings was negatively correlated with increasing litter depth and increasing soil *** density of saplings only showed a positive significant correlation with increasing *** nearest neighbor index showed a trend toward a positive spatial association between understory shrubs with their neighboring seedlings at a mean distance of 1.6 ***,the study highlighted the requirements for seedling regeneration as a relatively open canopy cover,a light understory litter layer,and noncompacted *** results are a step towards designing effective management and restoration programs.

关键词： Forest structure Litter depth Regeneration niche Spatial pattern Soil compaction

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Design and Development of Low-cost Wearable Electroencephalograms (EEG) Headset

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Intelligent Automation & Soft Computing 2023年第3期35卷 2821-2835页

作者： Riaz Muhammad ahmed ali M.Abid Anwar Toufique ahmed Soomro Omar AlShorman Adel Alshahrani mahmoud Masadeh Ghulam Md Ashraf Naif H.ali Muhammad Irfan Athanasios Alexiou Department of Electrical Engineering Sukkur IBA University65200SukkurPakistan Department of Electronic Engineering Quaid-e-Awam University of EngineeringScience and TechnologyLarkana77150Pakistan Faculty of Engineering and AlShrouk Trading Company Najran UniversityNajran61441Saudi Arabia Department of Medical Rehabilitation Sciences-Physiotherapy Program College of Applied Medical SciencesNajran UniversityNajran61441Saudi Arabia Computer Engineering Department Yarmouk UniversityIrbid21163Jordan Pre-Clinical Research Unit King Fahd Medical Research CenterKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Medical Laboratory Technology Faculty of Applied Medical SciencesKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Internal Medicine Medical CollegeNajran UniversityNajran61441Saudi Arabia Electrical Engineering Department College of EngineeringNajran University Saudi ArabiaNajran61441Saudi Arabia Novel Global Community Educational Foundation HebershamNSW 2770AustraliaAFNP Med AustriaWien2770Austria

Electroencephalogram(EEG)is a method of capturing the electrophy-siological signal of the *** EEG headset is a wearable device that records electrophysiological data from the *** paper presents the design and fab-rication of a customized low-cost Electroencephalogram(EEG)headset based on the open-source OpenBCI Ultracortex Mark IV *** electrode placement locations are modiﬁed under a 10–20 standard *** fabricated headset is then compared to commercially available headsets based on the following para-meters:affordability,accessibility,noise,signal quality,and ***,the data is recorded from 20 subjects who used the EEG Headset,and signals were ***,the participants marked the accuracy,set up time,participant comfort,and participant perceived ease of set-up on a scale of 1 to 7(7 being excellent).Thirdly,the self-designed EEG headband is used by 5 participants for slide *** raw EEG signal is decomposed into a series of band sig-nals using discrete wavelet transform(DWT).Lastly,theseﬁndings have been compared to previously reported *** concluded that when used for slide-changing control,our self-designed EEG headband had an accuracy of 82.0 *** also concluded from the results that our headset performed well on the cost-effectiveness scale,had a reduced setup time of 2±0.5 min(the short-est among all being compared),and demonstrated greater ease of use.

关键词： Brain-computer interface EEG consumer-grade accessibility headset

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Anti-wear properties evaluation of frictional sliding interfaces in automobile engines lubricated by copper/graphene nanolubricants

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Friction 2020年第5期8卷 905-916页

作者： Mohamed Kamal ahmed ali Xianjun HOU Mohamed AAABDELKAREEM Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Automotive and Tractors Engineering Department Faculty of EngineeringMinia UniversityEl-Minia 61111Egypt Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Owing to the significance of improving fuel economy, reducing emissions, and extending the durability of engine components, this study focused on the tribological performance of nano-additives. In this study, copper (Cu) and graphene (Gr) nanomaterials were dispersed in a fully formulated engine oil (5W-30) with different concentrations. The tribological trials were investigated under various speeds and loads, utilizing a reciprocating tribometer to mimic the ring/liner interfaces in the engine. The frictional surface morphologies were com-prehensively analyzed using electron probe X-ray microanalysis (EPMA), field emission scanning electron microscopy (FESEM), energy dispersive spectrometer (EDS), and three dimensional (3D) surface profilometry to explore the mechanisms responsible for improving the tribological performance of the frictional sliding parts in the engine. The tribological test results illustrated that lubrication by nano-additives reduced the wear rate (WR) and friction coefficient (COF) by 25%–30% and 26.5%–32.6%, respectively, as compared with 5W-30. The results showed that this is a promising approach for increasing the durability and lifespan of frictional sliding components and fuel economy in automobile engines.

关键词： engine tribology nanomaterial nanolubricant friction wear tribofilm

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Quantification of Urban Sprawl for Past-To-Future in Abha City,Saudi Arabia

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 755-786页

作者： Saeed AlQadhi Javed Mallick Swapan Talukdar ahmed ali Bindajam ahmed ali A.Shohan Shahfahad Department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography University of Gour BangaMalda732103India Department of Architecture and Planning College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography Faculty of Natural SciencesJamia Millia IslamiaNew Delhi110025India

Given that many cities in Saudi Arabia have been observing rapid urbanization since the 1990s,scarce studies on the spatial pattern of urban expansion in Saudi Arabia have been ***,the present study investigates the evidence of land use and land cover(LULC)dynamics and urban sprawl in Abha City of Saudi Arabia,which has been experiencing rapid urbanization,from the past to the future using novel and sophisticated *** SVM classifier was used in this study to classify the LULC maps for 1990,2000,and *** LULC dynamics between 1990–2000,2000–2018,and 1990–2018 have been analyzed using delta()change and the Markovian transitional probability *** sprawl or urban expansion was modeled using two approaches,such as landscape fragmentation and presence frequency for the first *** future LULC map for 2028 was predicted using the artificial neural network-cellular automata model(ANN-CA).Future LULC was analyzed using landscape fragmentation and frequency *** results of LULC maps showed that urban areas increased by 334.4%between 1990 and *** Delta change rate showed that 16.34%in urban areas has increased since ***,the transitional probability matrix between 1990 and 2018 reported that the built-up area is the largest stable LULC,having an 83.6%transitional probability *** 17.9%,21.8%,12.4%,and 10.5%of agricultural land,scrubland,exposed rocks,and water bodies were transformed into built-up *** sprawl models showed that 139 km^(2)of new urban areas had been set up in 2018,49 and 69 km^(2)in 1990 and ***,in 2018,more than 200%of urban areas were stabilized or became core urban *** future LULC map(2028)showed that the built-up area would be 343.72 km^(2),followed by scrubland(342.98 km^(2))and sparse vegetation(89.96 km^(2)).The new urban area in 2028 would be 169 km^(2).The authorities and planners should focus more on the sustainable development of urban areas;otherwise,it would

关键词： Urban sprawl LULC landscape fragmentation cellular automata SVM frequency approach

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Intelligent Deep Data Analytics Based Remote Sensing Scene Classification Model

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Computers, Materials & Continua 2022年第7期72卷 1921-1938页

作者： ahmed Althobaiti Abdullah Alhumaidi Alotaibi Sayed Abdel-Khalek suliman A.Alsuhibany Romany F.Mansour Department of Electrical Engineering College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Science and Technology College of RanyahTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Mathematics College of ScienceP.O.Box 11099Taif UniversityTaif21944Saudi Arabia Department of Computer Science College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharga72511Egypt

Latest advancements in the integration of camera sensors paves a way for newUnmannedAerialVehicles(UAVs)applications such as analyzing geographical(spatial)variations of earth science in mitigating harmful environmental impacts and climate *** have achieved significant attention as a remote sensing environment,which captures high-resolution images from different scenes such as land,forest fire,flooding threats,road collision,landslides,and so on to enhance data analysis and decision *** scene classification has attracted much attention in the examination of earth data captured by *** paper proposes a new multi-modal fusion based earth data classification(MMF-EDC)*** MMF-EDC technique aims to identify the patterns that exist in the earth data and classifies them into appropriate class *** MMF-EDC technique involves a fusion of histogram of gradients(HOG),local binary patterns(LBP),and residual network(ResNet)*** fusion process integrates many feature vectors and an entropy based fusion process is carried out to enhance the classification *** addition,the quantum artificial flora optimization(QAFO)algorithm is applied as a hyperparameter optimization *** AFO algorithm is inspired by the reproduction and the migration of flora helps to decide the optimal parameters of the ResNet model namely learning rate,number of hidden layers,and their number of ***,Variational Autoencoder(VAE)based classification model is applied to assign appropriate class labels for a useful set of feature *** proposedMMF-EDCmodel has been tested using UCM and WHU-RS *** proposed MMFEDC model attains exhibits promising classification results on the applied remote sensing images with the accuracy of 0.989 and 0.994 on the test UCM and WHU-RS dataset respectively.

关键词： Remote sensing unmanned aerial vehicles deep learning artificial intelligence scene classification

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Ding w-Flat Modules and Dimensions

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Algebra Colloquium 2018年第2期25卷 203-216页

作者： Fuad ali ahmed Almahdi Mohammed Tamekkante Department of Mathematics Faculty of Sciences King Khalid University P. O. Box. 9004 Abha Saudi Arabia Laboratory MACS Faculty of Sciences University Moulay Ismail 5000 P.B. 11201 Zitoune Meknes Morocco

The introduction of w-operation in the class of flat modules has been successful. Let R be a ring. An R-module M is called a w-fiat module if Tor1r（M, N） is GV-torsion for all R-modules N. In this paper, we introduce the w-operation in Gorenstein homological algebra. An R-module M is called Ding w-flat if there exists an exact sequence of projective R-modules ... → P1 → P0 → p0 → p1 → ... such that M Im（P0 → p0） and such that the functor HomR （-,F） leaves the sequence exact whenever F is w-flat. Several well- known classes of rings are characterized in terms of Ding w-flat modules. Some examples are given to show that Ding w-flat modules lie strictly between projective modules and Gorenstein projective modules. The Ding w-flat dimension （of modules and rings） and the existence of Ding w-flat precovers are also studied.

关键词： w-fiat module and dimension Gorenstein projective module and dimension,strongly Gorenstein flat module

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