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Some aspects affecting the response of RC compartment structures subjected to internal blast loads

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 135-148页

作者： Osman M.O.Ramadan M.Galal El Sherbiny Ahmed M.khalil Faculty of Engineering Cairo UniversityCairo 12411Egypt Higher Technological Institute(HTI)at 10th of Ramadan City Sharqia 13658Egypt Structural Engineering and Construction Management Department Faculty of Engineering&TechnologyFutureUniversity in Egypt-FUECairo 16383Egypt

Protective compartments are typically used to protect some specific structures from internal explosions,such as industrial buildings that contain devices that may explode in certain *** research investigates how the response of reinforced concrete(RC)compartment structures subjected to internal blast loads are affected by the following aspects:introduction of material nonlinearity in the analysis,reinforcement ratio,and aspect ratio of the *** achieve this goal,a calibrated and sophisticated FE numerical model is introduced,and a parametric study for the intended aspects is carried out.A discussion of the results and conclusions are offered,which show the role of each aspect in the dynamic performance of the compartment *** main conclusions are as follows:introduction of material nonlinearity in this type of analysis and for these structures is very important and significant in obtaining accurate outputs that are similar to actual behavior;the reinforcement ratio has a significant effect on the response and its effect varies depending on the thickness of the compartment;in general,increasing the reinforcement ratio enhances the behavior and reduces the stresses in the compartment;and the aspect ratio of the compartment does not show a clear pattern on the response of such structures under internal blast loads.

关键词： blast loads protective structures nonlinear analysis explicit dynamic analysis

Numerical Exploration of Asymmetrical Impact Dynamics: Unveiling Nonlinearities in Collision Problems and Resilience of Reinforced Concrete Structures

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Structural Durability & Health Monitoring 2024年第3期18卷 223-254页

作者： AL-Bukhaiti khalil Yanhui Liu Shichun Zhao Daguang Han School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Faculty of Civil Engineering Southeast UniversityNanjingChina

This study provides a comprehensive analysis of collision and impact problems’ numerical solutions, focusing ongeometric, contact, and material nonlinearities, all essential in solving large deformation problems during a *** initial discussion revolves around the stress and strain of large deformation during a collision, followedby explanations of the fundamental finite element solution method for addressing such issues. The hourglassmode’s control methods, such as single-point reduced integration and contact-collision algorithms are detailedand implemented within the finite element framework. The paper further investigates the dynamic responseand failure modes of Reinforced Concrete (RC) members under asymmetrical impact using a 3D discrete modelin ABAQUS that treats steel bars and concrete connections as bond slips. The model’s validity was confirmedthrough comparisons with the node-sharing algorithm and system energy relations. Experimental parameterswere varied, including the rigid hammer’s mass and initial velocity, concrete strength, and longitudinal and stirrupreinforcement ratios. Findings indicated that increased hammer mass and velocity escalated RC member damage,while increased reinforcement ratios improved impact resistance. Contrarily, increased concrete strength did notsignificantly reduce lateral displacement when considering strain rate effects. The study also explores materialnonlinearity, examining different materials’ responses to collision-induced forces and stresses, demonstratedthrough an elastic rod impact case study. The paper proposes a damage criterion based on the residual axialload-bearing capacity for assessing damage under the asymmetrical impact, showing a correlation betweendamage degree hammer mass and initial velocity. The results, validated through comparison with theoreticaland analytical solutions, verify the ABAQUS program’s accuracy and reliability in analyzing impact problems,offering valuable insights into collision

关键词： Geometric nonlinearity contact nonlinearity material nonlinearity collision problems finite element method stress and strain damage criterion RC members asymmetrical impact

Improved Spallation Resistance of the Oxide Scale by Hf/Y Co-doping in Ni-Based Superalloy at High Temperature

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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1744-1758页

作者： khalil Rehman Naicheng Sheng Shigang Fan Shijie Sun Guicheng Hou Yizhou Zhou Xiaofeng Sun Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Material Science and Engineering University of Science and Technology of ChinaHefei230026China

Ni-based superalloys added with comparably higher concentrations of single-doped Hf and co-doped Hf/Y are prepared by vacuum induction melting(VIM).The oxidation properties up to 300 h at 900℃,1000℃,and 1100℃ are *** undoped alloy exhibited a minimum oxidation rate at 900℃ and 1000℃.The co-doped alloy showed a higher oxidation rate;however,it possesses better scale adhesion,and no spallation ***-doped alloy showed a lower oxidation rate and better scale adhesion at 900℃ and 1000℃,but exhibited a shorter lifetime at 1100℃.The spallation of the Hf-doped alloy is attributed to the precipitation of the HfO2 in and beneath the oxide *** spallation in the undoped alloy is accredited to the thermal expansion mismatch between the growing oxide scale and superalloy *** two reactive elements(REs)in alloy minimized the precipitation of RE oxide in the oxide scale,diminished internal oxidation in the alloy,and decreased oxide scale spallation.

关键词： Superalloys Reactive elements Oxidation kinetics Microstructure Spallation resistance

Silicon micromirrors with three-dimensional curvature enabling lensless efficient coupling of free-space light

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Light(Science & Applications) 2013年第1期2卷 98-106页

作者： Yasser M Sabry Bassam Saadany Diaa khalil Tarik Bourouina Universite Paris-Est ESYCOM(EA 2552)ESIEE ParisF-93162 Noisy-le-GrandFrance Si-Ware Systems 3 Khaled Ibn El-Waleed StreetHeliopolisCairo 11361Egypt Electron.and Comm.Eng.Dept. Faculty of Eng.Ain-Shams UniversityCairoEgypt

Miniaturized optical benches process free-space light propagating in-plane with respect to the substrate and have a large variety of applications,including the coupling of light through an optical *** coupling efficiency is usually obtained using assembled micro-optical parts,which considerably increase the system cost and integration *** this work,we report a high coupling efficiency,monolithically integrated silicon micromirror with controlled three-dimensional(3D)curvature that is capable of manipulating optical beams propagating in the plane of the silicon *** on our theoretical modeling,a spherical micromirror with a microscale radius of curvature as small as twice the Gaussian beam Rayleigh range provides a 100%coupling efficiency over a relatively long optical path *** dimensionless parameters facilitates the elucidation of the role of key design parameters,including the mirror’s radii of curvature,independent of the wavelength.A micromachining method is presented for fabricating the 3D micromirror using fluorinated gas *** measured coupling efficiency was greater than 50%over a 200-mm optical path,compared to less than 10%afforded by a conventional flat micromirror,which was in good agreement with the *** the 3D micromirror,an optical cavity was formed with a round-trip diffraction loss of less than 0.4%,resulting in one order of magnitude enhancement in the measured quality factor.A nearly 100%coupling was also estimated when matching the sagittal and tangential radii of curvature of the presented micromirror’s *** reported class of 3D micromirrors may be an advantageous replacement for the optical lenses usually assembled in silicon photonics and optical benches by transforming them into real 3D monolithic systems while achieving wideband high coupling efficiency over submillimeter distances.

关键词： coupling efficiency Gaussian beam coupling micro-optics monolithic chip optical cavity optical fabrication optical benches silicon photonics

Sentiment Analysis of Low-Resource Language Literature Using Data Processing and Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 713-733页

作者： Aizaz Ali Maqbool Khan khalil Khan Rehan Ullah Khan Abdulrahman Aloraini Department of IT and Computer Science Pak-Austria Fachhochschule:Institute of Applied Sciences and TechnologyHaripur22620Pakistan Software Competence Center Hagenberg Softwarepark 32aHagenberg4232Austria Department of Computer Science School of Engineering and Digital SciencesNazarbayev UniversityAstana010000Kazakhstan Department of Information Technology College of ComputerQassim UniversityP.O.Box 1162BuraydahSaudi Arabia

Sentiment analysis, a crucial task in discerning emotional tones within the text, plays a pivotal role in understandingpublic opinion and user sentiment across diverse *** numerous scholars conduct sentiment analysisin widely spoken languages such as English, Chinese, Arabic, Roman Arabic, and more, we come to grapplingwith resource-poor languages like Urdu literature which becomes a challenge. Urdu is a uniquely crafted language,characterized by a script that amalgamates elements from diverse languages, including Arabic, Parsi, Pashtu,Turkish, Punjabi, Saraiki, and more. As Urdu literature, characterized by distinct character sets and linguisticfeatures, presents an additional hurdle due to the lack of accessible datasets, rendering sentiment analysis aformidable undertaking. The limited availability of resources has fueled increased interest among researchers,prompting a deeper exploration into Urdu sentiment analysis. This research is dedicated to Urdu languagesentiment analysis, employing sophisticated deep learning models on an extensive dataset categorized into fivelabels: Positive, Negative, Neutral, Mixed, and Ambiguous. The primary objective is to discern sentiments andemotions within the Urdu language, despite the absence of well-curated datasets. To tackle this challenge, theinitial step involves the creation of a comprehensive Urdu dataset by aggregating data from various sources such asnewspapers, articles, and socialmedia comments. Subsequent to this data collection, a thorough process of cleaningand preprocessing is implemented to ensure the quality of the data. The study leverages two well-known deeplearningmodels, namely Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN), for bothtraining and evaluating sentiment analysis performance. Additionally, the study explores hyperparameter tuning tooptimize the models’ efficacy. Evaluation metrics such as precision, recall, and the F1-score are employed to assessthe effectiv

关键词： Urdu sentiment analysis convolutional neural networks recurrent neural network deep learning natural language processing neural networks

Bipolar Interval-Valued Neutrosophic Optimization Model of Integrated Healthcare System

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Computers, Materials & Continua 2022年第12期73卷 6207-6224页

作者： Sumbal khalil Sajida Kousar Nasreen Kausar Muhammad Imran Georgia Irina Oros Department of Mathematics and Statistics International Islamic UniversityIslamabadPakistan Department of Mathematics Faculty of Arts and SciencesYildiz Technical UniversityEsenler34210IstanbulTurkey NUST Business School Islamabad Pakistan Department of Mathematics and Computer Science University of OradeaOradea410087Romania

Bipolar Interval-valued neutrosophic set is another generalization of fuzzy set,neutrosophic set,bipolar fuzzy set and bipolar neutrosophic set and thus when applied to the optimization problem handles uncertain data more efficiently and *** work is an effort to design a flexible optimization model in the backdrop of interval-valued bipolar neutrosophic *** interval-valued neutrosophic membership grades are picked so that they indicate the restriction of the plausible infringement of the inequalities given in the *** prove the adequacy and effectiveness of the method a unified system of sustainable medical healthcare supply chain model with an uncertain figure of product complaints is ***,quality and cost are considered as satisfaction level to choose best supplier for medicine *** proposed model ensures 99%satisfaction for cost reduction,63%satisfaction for the quality of product and 64%satisfaction for total time taken in medicine supply chain.

关键词： Bipolar fuzzy set neutrosophic set interval-valued neutrosophic set bipolar interval-valued neutrosophic set supply chain fuzzy optimization

Debt choice, growth opportunities and corporate investment: evidence from China

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Financial Innovation 2020年第1期6卷 645-666页

作者： Ning Ding Kalimullah Bhat khalil Jebran School of Finance Dongbei University of Finance and EconomicsDalianChina School of Business Administration Dongbei University of Finance and EconomicsDalianChina

The study aims to investigate how relying on short-term debt may help Chinese listed firms to make efficient investment decisions and reduce overinvestment problem for low-growth *** study uses a large set of panel data of nonfinancial Chinese listed firms over the period 2007–2017 and,using the robust twostage generalized method of moments,which is robust to unobserved heterogeneity of individual firms and addresses endogeneity *** show a positive relationship between growth and investment;this association is enhanced by leverage,especially for high-growth *** supports the view that short-term debt helps Chinese firms to make optimal use of leverage and therefore make better investment ***,the results reveal that leverage plays a disciplining and monitoring role to reduce overinvestment incentive for low-growth ***,the study suggests that shareholders should consider short-term debt to mitigate the debt overhang problem and restrict the opportunistic behavior of managers,which can lead to efficient investment *** also provides foreign investors insights about capital structure in China,and how it can help them make better investment decisions.

关键词： Chinese firms Leverage Growth Investment

Data-driven modeling on anisotropic mechanical behavior of brain tissue with internal pressure

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Defence Technology（防务技术） 2024年第3期33卷 55-65页

作者： Zhiyuan Tang Yu Wang khalil I.Elkhodary Zefeng Yu Shan Tang Dan Peng State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of Technology116023DalianPR China The Department of Mechanical Engineering The American University in CairoNew Cairo11835Egypt Department of Neurology The Second Hospital of Dalian Medical UniversityDalian116023PR China

Brain tissue is one of the softest parts of the human body,composed of white matter and grey *** mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain ***,traumatic brain injury(TBI)and various brain diseases are also greatly influenced by the brain's mechanical *** white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical *** such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional *** a constitutive law for multiscale brain tissue using traditional function-based approaches can be very ***,this paper proposes a data-driven approach to establish the desired mechanical model of brain *** focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our *** matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading *** generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal ***,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body *** with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling *** predictions made by our trained model demonstrate sufficient ***,we find that the level of internal blood pressur

关键词： Data driven Constitutive law Anisotropy Brain tissue Internal pressure

The intention of banks to adopt green banking in an emerging market:the employees’perspective

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Economic and Political Studies 2021年第4期9卷 497-504页

作者： Eugene Okyere-Kwakye khalil Md Nor aFaculty of Business and Management Studies Koforidua Technical UniversityKoforiduaGhana bFaculty of Management University of Technology Malaysia(UTM)Johor BahruMalaysia

Green banking is a comparatively new development in the financial *** is a form of banking that considers the social and environmental impacts of banking *** studies on green banking focussed on customers,management,and other stakeholders without considering the perspective of employees,whose daily work is normally *** fill in the gap,the primary aim of this study is to assess factors affecting the intention of banks to adopt green banking from the perspective of employees.A questionnaire was used to collect data from 94 employees at selected banks in Koforidua,the eastern region of *** regression was used to analyse the *** study finds a significantly positive relationship between management support and intention of banks to adopt green ***,pressures from competitors and customers are found not to have a significant impact on banks’intention to adopt green *** these results are unexpected and disappointing,they provide important insights in the context that changing initiatives from the perspective of common employees are internally driven instead of externally *** suggests the importance of management’s role in facilitating green banking initiatives.

关键词： Green banking competitor pressure customer pressure management support