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Concircular π-Vector Fields and Special Finsler Spaces

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Advances in Pure Mathematics 2013年第2期3卷 282-291页

作者： Nabil L. Youssef amr soleiman Department of Mathematics Faculty of Science Benha University Benha Egypt Department of Mathematics Faculty of Science Cairo University Giza Egypt Center for Theoretical Physics (CTP) The British University in Egypt (BUE) Cairo Egypt

The aim of the present paper is to investigate intrinsically the notion of a concircular π-vector field in Finsler geometry. This generalizes the concept of a concircular vector field in Riemannian geometry and the concept of concurrent vector field in Finsler geometry. Some properties of concircular π-vector fields are obtained. Different types of recurrence are discussed. The effect of the existence of a concircular π-vector field on some important special Finsler spaces is investigated. Almost all results obtained in this work are formulated in a coordinate-free form.

关键词： Finsler Manifold Cartan Connection Concurrent π-Vector Field Concircular π-Vector Field Special Finsler Space Recurrent Finsler Space

Asphaltene onset pressure measurement and calculation techniques:A review

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Petroleum 2024年第2期10卷 191-201页

作者： Sherif Fakher amr Yousef Aseel Al-Sakkaf Shams Eldakar Petroleum and Energy Engineering The American University in Cairo

Asphaltene precipitation can result in several production, operational, and transportation problems during oil recovery. If asphaltene precipitates and deposits, it can reduce reservoir permeability, damage wellbore equipment, and plug the pipelines. It is therefore extremely important to evaluate the conditions at which asphaltene precipitation occurs; this is referred to as the asphaltene onset *** onset pressure has been measured using many different experimental techniques. There have also been many attempts along the years to predict asphaltene onset pressure using mathematical correlations and models. This research provides an up-to-date comprehensive review of the methods by which asphaltene onset pressure can be measured using laboratory experiments and mathematical models. The research explains the main mechanisms of all the laboratory experiments to measure asphaltene onset pressure under static conditions and how to conduct them and highlights the advantages and limitations of each method. The research also provides a summary of the commonly used mathematical models to quantify asphaltene onset pressure directly and indirectly.

关键词： Asphaltene onset measurement

Node Sociability Based Intelligent Routing for Post-Disaster Emergency Networks

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China Communications 2024年第8期21卷 104-114页

作者： Li Jiameng Xiong Xuanrui Liu Min amr Tolba School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Graduate School of Information Production and SystemsWaseda UniversityFukuoka 808-0135Japan School of Communications and Information Engineering Chongqing College of Mobile CommunicationChongqing 401520China Computer Science Department Community CollegeKing Saud UniversityRiyadh 11437Saudi Arabia

In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are *** the“store-carry-forward”mechanism characteristic of Delay Tolerant Networks(DTNs)can transmit data from Internet of things devices to more reliable base stations or data centres,it also suffers from inefficient data transmission and excessive transmission *** address these challenges,we propose an intelligent routing strategy based on node sociability for post-disaster emergency network ***,we introduce an intelligent routing strategy based on node intimacy,which selects more suitable relay nodes and assigns the corresponding number of message copies based on comprehensive utility ***,we present an intelligent routing strategy based on geographical location of nodes to forward message replicas secondarily based on transmission utility ***,experiments demonstrate the effectiveness of our proposed algorithm in terms of message delivery rate,network cost ratio and average transmission delay.

关键词： delay tolerant networks Internet of things node sociability routing strategy

Improved combustion stability of biogas at different CO_(2) concentrations using inhomogeneous partially premixed stratified flames

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Global Energy Interconnection 2024年第4期7卷 486-502页

作者： Mohy Saad Mansour Maged Kiriakos Lili Hao Mohamed amr Serag-Eldin Mechanical Power Engineering Department Cairo University1 Gamaa StreetCairo Governorate 12613Egypt Mechanical Engineering Department The American University in CairoAUC AveCairo Governorate 11835Egypt College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816P.R.China

Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon *** high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas *** improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this *** thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame *** flame size was reduced by increasing the CO_(2) concentration and the flames became lighter *** flame temperature also decreased with increase in CO_(2) *** stability was reduced by increasing the CO_(2) ***,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the ***,the IPPS mode of combustion should be suitable for the combustion and stabilization of *** should support the design of highly stabilized biogas turbulent flames independent of CO_(2) *** data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant.

关键词： Biogas Renewable energy Effect of CO_(2) Combustion stability Burner design Renewable fuels Partial premixed

Advancing sandstone reservoir compressibility prediction:A correlation-driven methodology

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Petroleum Research 2024年第2期9卷 273-279页

作者： Tarek Ganat Meftah Hrairi amr Badawy Vahid Khosravi Mohammed Abdalla Department of Petroleum Chemical Engineering Sultan Qaboos UniversityP.O.Box 50Al-Khod123MuscatOman Department of Mechanical and Aerospace Engineering International Islamic University MalaysiaP.O.Box 1050728Kuala LumpurMalaysia Reservoir Engineering Section Petronas Carigali SDN BHDP.O.Box 10500088Kuala LumpurMalaysia Department of Chemical and Petroleum Engineering Faculty of EngineeringTechnologyand Built EnvironmentUCSI University56000Kuala LumpurMalaysia Chemical&Petroleum Engineering United Arab Emirates UniversityP.O.Box No.15551Al AinUAE

This study presents a correlation-based approach for predicting the compressibility of sandstone reservoir *** study proposes a matrix of new empirical equations that significantly improve the precision of measuring the pore volume compressibility,with the most optimal fit of results based on a cubic polynomial *** accuracy of the calculations was validated through comparison with actual data using root mean square method,and the suggested correlations significantly enhance the precise prediction of rock compressibility in sandstone *** this study,the source of data collection is consolidated and unconsolidated sandstone from East Asia offshore ***,variations in compressibility with net overburden pressure over the course of the field's lifespan have been *** results demonstrate the application of regression analysis in establishing a network of linkages between independent and dependent *** proposed correlations for consolidated and unconsolidated sandstones offer a remarkable improvement in the accurate calculation of rock compressibility compared to traditional laboratory procedures,with an average error of 2.5%compared to 5-10%for laboratory *** approach of this study offers a cost-effective and time-efficient alternative to remarkedly enhance the overall performance of sandstone reservoirs in the oil and gas industry.

关键词： Compressibility Consolidated and unconsolidated sandstone Rock properties Rock mechanics

SwinVid:Enhancing Video Object Detection Using Swin Transformer

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Computer Systems Science & Engineering 2024年第2期48卷 305-320页

作者： Abdelrahman Maharek amr Abozeid Rasha Orban Kamal ElDahshan Computer Science Department Faculty of Artificial Intelligence and InformaticsBenhaEgypt Mathematics Department Faculty of SciencesAl-Azhar UniversityCairoEgypt Department of Computer Science College of Science and Arts in QurayyatJouf UniversitySakakaSaudi Arabia

What causes object detection in video to be less accurate than it is in still images?Because some video frames have degraded in appearance from fast movement,out-of-focus camera shots,and changes in *** reasons have made video object detection(VID)a growing area of research in recent *** object detection can be used for various healthcare applications,such as detecting and tracking tumors in medical imaging,monitoring the movement of patients in hospitals and long-term care facilities,and analyzing videos of surgeries to improve technique and ***,it can be used in telemedicine to help diagnose and monitor patients *** VID techniques are based on recurrent neural networks or optical flow for feature aggregation to produce reliable features which can be used for *** of those methods aggregate features on the full-sequence level or from nearby *** create feature maps,existing VID techniques frequently use Convolutional Neural Networks(CNNs)as the backbone *** the other hand,Vision Transformers have outperformed CNNs in various vision tasks,including object detection in still images and image *** propose in this research to use Swin-Transformer,a state-of-the-art Vision Transformer,as an alternative to CNN-based backbone networks for object detection in *** proposed architecture enhances the accuracy of existing VID *** ImageNet VID and EPIC KITCHENS datasets are used to evaluate the suggested *** have demonstrated that our proposed method is efficient by achieving 84.3%mean average precision(mAP)on ImageNet VID using less memory in comparison to other leading VID *** source code is available on the website https://***/amaharek/SwinVid.

关键词： Video object detection vision transformers convolutional neural networks deep learning

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Energy Management

Journal of Energy and Power Engineering 2024年第1期18卷 29-33页

作者： Khaled(Moh’d Khalaf)soleiman Alnobani Department of Chemical Engineering Jordan University of Science and TechnologyIrbid 22110Jordan

A new revised energy concept is proposed from relativistic approach using different kinds of *** is not always feasible to implement a project for saving *** is not merely heating a stream and cooling another *** study includes other considerations.A total feasibility study should be *** cost and the income should be *** this study it is shown how to perform such a feasibility study from scratch up to detailed *** is an investment *** are two energy balances:one thermal and the other *** are not separated but they complete each *** decision is upon rigorous energy *** the question where the energy will go shall be answered from 2nd law of thermodynamics.

关键词： Entropy energy feasibility study

A Hybrid Classification and Identification of Pneumonia Using African Buffalo Optimization and CNN from Chest X-Ray Images

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2497-2517页

作者： Nasser Alalwan Ahmed I.Taloba amr Abozeid Ahmed Ibrahim Alzahrani Ali H.Al-Bayatti Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Information System Department Faculty of Computers and InformationAssiut UniversityAssiutEgypt Mathematics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt Cyber Technology Institute(CTI) De Montfort UniversityLeicesterUK

An illness known as pneumonia causes inflammation in the *** there is so much information available fromvarious X-ray images,diagnosing pneumonia has typically proven *** improve image quality and speed up the diagnosis of pneumonia,numerous approaches have been *** date,several methods have been employed to identify *** Convolutional Neural Network(CNN)has achieved outstanding success in identifying and diagnosing diseases in the fields of medicine and ***,these methods are complex,inefficient,and imprecise to analyze a big number of *** this paper,a new hybrid method for the automatic classification and identification of Pneumonia from chest X-ray images is *** proposed method(ABOCNN)utilized theAfrican BuffaloOptimization(ABO)algorithmto enhanceCNNperformance and *** Weinmed filter is employed for pre-processing to eliminate unwanted noises from chest X-ray images,followed by feature extraction using the Grey Level Co-Occurrence Matrix(GLCM)*** features are then selected from the dataset using the ABO algorithm,and ultimately,high-performance deep learning using the CNN approach is introduced for the classification and identification of *** results on various datasets showed that,when contrasted to other approaches,the ABO-CNN outperforms them all for the classification *** proposed method exhibits superior values like 96.95%,88%,86%,and 86%for accuracy,precision,recall,and F1-score,respectively.

关键词： African buffalo optimization convolutional neural network pneumonia X-ray

3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1365-1384页

作者： Dun Cao Jia Ru Jian Qin amr Tolba Jin Wang Min Zhu College of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China Department of Computer Science Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia College of Information Science and Technology Zhejiang Shuren UniversityHangzhou310015China

Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time *** modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is *** paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety.

关键词： Internet of vehicles road networks 3D road model structure recognition GIS