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Experimental and numerical study of effecting core configurations on the static and dynamic behavior of honeycomb plate with aluminum material

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DEFENCE TECHNOLOGY 2024年第9期39卷 177-192页

作者： Hamza, Nehad Abid Allah AL-Fatlwe, Fatima Mohammed k. Talib, Muna Ali Al Qasim Green Univ Engn Coll Babylon 51013 Iraq Al Furat Al Awsat Tech Univ ATU Engn Tech Coll Al Najaf Najaf 54003 Iraq

The sandwich panel incorporated a honeycomb core, a widely utilized composite structure recognized as a fundamental classification of composite materials. Comprised a core resembling a honeycomb, possessing thick.ess and softness, and is flank.by rigid face sheets that sandwich various shapes and materials. This paper presents an examination of the static and dynamic analysis of lightweight plates made of aluminum honeycomb sandwich composites. Honeycomb sandwich plate samples are 300 mm long, and 300 mm wide, the heights of the core have been varied at four values ranging from 10 to 25 mm. The honeycomb core is manufactured from Aluminum material by using a novel technique namely resistance spot welding (RSW) instead of using adhesive material, which is often used when an industrial flaw is detected. Numerical optimization based on response surface methodology (RSM) and design of experiment software (DOE) was used to verify the current work. A theoretical examination of the crashworthiness behavior (maximum bending load, maximum deflection) and vibration attributes (natural frequency, damping ratio, transient temporal response) of honeycomb sandwich panels with different design parameters was also carried out. In addition, the finite element method-based ANSYS software was used to confirm the theoretical conclusions. The findings of the present work.showed that the relationship between the natural frequency, core height, and cell size is direct. In contrast, the relationship between the natural frequency and the thick.ess of the cell wall is inverse. Conversely, the damping ratio is inversely proportional to the core height and cell size but directly proportional to the thick.ess of the cell wall. The study indicates that altering the core height within 10-25 mm leads to a significant increase of 82 % in the natural frequency and a notable decrease of 49% in the damping ratio. These findings are based on a specific cell size value of 0.01 m and a cell wall thick.es

关键词： Honeycomb Load Transient response Free vibration Natural frequency SANDWICH PANELS

LiDAR-based estimation of bounding box coordinates using Gaussian process regression and particle swarm optimization

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Biomimetic Intelligence & Robotics 2024年第1期4卷 24-35页

作者： Vinodha k. E.S.Gopi Tushar Agnibhoj Department of Electronics and Communication Engineering National Institute of Technology TiruchirappalliTamil Nadu620015India

Camera-based object track.ng systems in a given closed environment lack.privacy and *** this study,light detection and ranging(LiDAR)was applied to track.objects similar to the camera track.ng in a closed environment,guaranteeing privacy and *** primary objective was to demonstrate the efficacy of the proposed technique through carefully designed experiments conducted using two *** Scenario I,the study illustrates the capability of the proposed technique to detect the locations of multiple objects positioned on a flat surface,achieved by analyzing LiDAR data collected from several locations within the closed *** II demonstrates the effectiveness of the proposed technique in detecting multiple objects using LiDAR data obtained from a single,fixed ***-time experiments are conducted with human subjects navigating predefined *** individuals move within an environment,while LiDAR,fixed at the center,dynamically track. and identifies their locations at multiple *** demonstrate that a single,strategically positioned LiDAR can adeptly detect objects in motion around ***,this study provides a comparison of various regression techniques for predicting bounding box *** process regression(GPR),combined with particle swarm optimization(PSO)for prediction,achieves the lowest prediction mean square error of all the regression techniques examined at *** tuning of GPR using PSO significantly minimizes the regression *** of the experiment pave the way for its extension to various real-time applications such as crowd management in malls,surveillance systems,and various Internet of Things scenarios.

关键词： LiDAR Data acquisition Bounding box Gaussian process regression Particle swarm optimization(PSO)

Assessing the biennial conference on science and technology (BICOST IX) 2023 technical output on renewable energy, energy storage, and green hydrogen in line with UN SDG commitments

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CLEAN ENERGY 2024年第2期8卷 85-88页

作者： Silva, S. k. B. D. Piyumali, k. G. D. Perera, Rasitha Thilini Suranjana k.luarachchi, k. D. k. G. Munagamage, Thilini Ahammed, R. M. R. Piyank.rage, C. S. P. Shahmy, Seyed k.runaratne, Veranja Natl Sci & Technol Commiss Sri Lank. Colombo Sri Lanka Sri Lank. Technol Campus Padukka 10500 Sri Lanka Univ Peradeniya Peradeniya Sri Lanka

The development, production and utilization of renewable energy, energy storage and green hydrogen and the associated technologies in Sri Lank. have great potential to contribute to the United Nations' Sustainable Development Goals (SDGs). The island aims to achieve 70% electricity generation from renewable energy sources by 2030 (within the target of 40% utilization of renewable energy sources for the entire energy generation of the country by 2030). The power sector has to invest US$11 billion from 2023 to 2030 to contribute to reaching this target. This commentary aims to provide a critical perspective on the recommendations of the report from the National Science and Technology Commission's 9th biennial conference in 2023 on science and technology, the sub-thematic technical report on clean energy, energy storage and green hydrogen in line with the SDGs in the Sri Lank.n context. The technical report provides insightful recommendations for Sri Lank.'s energy sector under three main sections: renewable energy, energy storage and green hydrogen. Also, it explores the potential of various renewable energy sources, energy storage systems and green hydrogen as sustainable solutions to address the country's energy challenges while emphasizing the spillover effects of them, which could contribute to the enterprise's job creation and uplift the economy. This commentary provides a critical perspective on clean energy, energy storage and green hydrogen in line with the United Nations SDGs in the Sri Lank.n context based on a recent report from the National Science and Technology Commission of Sri Lank.. Graphical Abstract

关键词： renewable energy energy storage green hydrogen sustainable development goals Sri Lank. social economic environmental sustainable affordable

A new route to weak.force sensing beyond SQL: Squeezed magnons in cavity magnomechanics

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 170-171页

作者： ?.k.?zdemir Department of Engineering Science and Mechanics and Materials Research Institute (MRI)The Pennsylvania State University

Quantum mechanics imposes limits on measurement accuracy through quantum noise which typically has two components: First is the shot noise originating from vacuum fluctuations and referred to as the imprecision noise. Second is the quantum back.ction originating from the “action” of the measurement back.on the object being measured.

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Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquak. Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquak. event has increasingly become an important component of performance-based earthquak. engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquak. magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the break.oint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquak. magnitudes less than 7 or epicentral distances greater than 20 k..

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Analysis of the Oscillatory Flows of Multiple Shock.Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k.JAMES Jintu k.M Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT k.rea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock.waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock.waves are formed inside the duct at a shock.Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock.oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock.*** oscillatory response of shock.waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock.train leading-edge location,shock.train length,and the size of the separation *** extent of the initial shock.location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock.train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock.train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock.train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrink. during the shock.oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock.train downstream disturbance supersonic flow shock.wave boundary layer interaction duct resonance flow separation

Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work.investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while k.eping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k.350 k.and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer

Radiative heat transfer analysis of a concave porous fin under the local thermal non-equilibrium condition:application of the clique polynomial method and physics-informed neural network.

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1613-1632页

作者： k.CHANDAN k.k.RTHIk.k.V.NAGARAJA B.C.PRASANNAk.MARA R.S.VARUN k.MAR T.MUHAMMAD Amrita School of Artificial Intelligence Amrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Studies in Mathematics Davangere UniversityDavangere 577002KarnatakaIndia Computational Science Lab Amrita School of EngineeringAmrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Pure and Applied Mathematics School of Mathematical SciencesSunway UniversityPetaling Jaya 47500Malaysia Department of Mathematics College of ScienceKing Khalid UniversityAbha 61413Saudi Arabia

The heat transfer through a concave permeable fin is analyzed by the local thermal non-equilibrium(LTNE)*** governing dimensional temperature equations for the solid and fluid phases of the porous extended surface are modeled,and then are nondimensionalized by suitable dimensionless ***,the obtained nondimensional equations are solved by the clique polynomial method(CPM).The effects of several dimensionless parameters on the fin's thermal profiles are shown by graphical ***,the current study implements deep neural structures to solve physics-governed coupled equations,and the best-suited hyperparameters are attained by comparison with various network.*** results of the CPM and physicsinformed neural network.PINN)exhibit good agreement,signifying that both methods effectively solve the thermal modeling problem.

关键词： heat transfer fin porous fin local thermal non-equilibrium(LTNE)model physics-informed neural network.PINN)

Exploring public perception and willingness to pay for a renewable source of energy: evidence from an emerging economy of renewable-energy development

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CLEAN ENERGY 2024年第2期8卷 177-188页

作者： Bashir, Mohammed J. k. Abdelhak. Senadjk. Salah, Wael A. Abuhelwa, Mai Cent Queensland Univ Sch Engn & Technol 120 Spencer St Melbourne Qld 3000 Australia Univ Tunk. Abdul Rahman Fac Business & Finance Kampar Perak Malaysia Palestine Tech Univ k.doorie Coll Engn & Technol Dept Elect Engn POB 7 Yafa St Tulkarm Palestine Univ Missouri Dept Elect Engn & Comp Sci Columbia MO 65211 USA

The study focuses on the transition from conventional energy sources to sustainable renewable energy (RE) in Palestine, particularly in the West Bank.and Gaza Strip. The research aims to understand the relationship between k.y factors and residents' willingness to invest in the RE sector, with a specific focus on the impact of education. Using the unified theory of acceptance and use of technology, the study analyzes data from 400 residents through a questionnaire and employs ordinary least-squares regression analysis with Eviews 12. The k.y findings indicate that residents' inclination to invest in RE is significantly influenced by factors such as resource availability, k.owledge level and power outages. Moreover, the study suggests that educated residents are more lik.ly to invest in RE when factors such as k.owledge, effort expectation, enabling conditions and resource availability are relatively high. The conclusion emphasizes the importance of policymak.rs' allocating sufficient funds to research and development to promote technological innovation in RE sources, thereby enhancing the population's energy efficiency. The study focuses on the transition from conventional energy to sustainable renewable energy in Palestine, particularly in the West Bank.and Gaza Strip, to understand the relationship between k.y factors and residents' willingness to invest in the RE sector, with a specific focus on the impact of education. Graphical Abstract

关键词： renewable energy technology energy security public perceptions sustainable development UNIFIED THEORY RURAL-AREAS TECHNOLOGY ACCEPTANCE DETERMINANTS INTENTION RELIABILITY SERVICES SYSTEM ERRORS