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Salp Swarm Incorporated Adaptive Dwarf Mongoose Optimizer with Lévy Flight and Gbest-Guided Strategy

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Journal of Bionic Engineering 2024年第4期21卷 2110-2144页

作者： Gang Hu Yuxuan Guo Guanglei Sheng department of Applied Mathematics Xi’an University of TechnologyXi’an710054People’s Republic of China School of Computer Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China department of Electronics and Information Engineering Bozhou UniversityBozhou236800People’s Republic of China

In response to the shortcomings of Dwarf Mongoose Optimization(DMO)algorithm,such as insufficient exploitation capability and slow convergence speed,this paper proposes a multi-strategy enhanced DMO,referred to as ***,we propose an improved solution search equation that utilizes the Gbest-guided strategy with different parameters to achieve a trade-off between exploration and exploitation(ee).Secondly,the Lévy flight is introduced to increase the diversity of population distribution and avoid the algorithm getting stuck in a local *** addition,in order to address the problem of low convergence efficiency of DMO,this study uses the strong nonlinear convergence factor Sigmaid function as the moving step size parameter of the mongoose during collective activities,and combines the strategy of the salp swarm leader with the mongoose for cooperative optimization,which enhances the search efficiency of agents and accelerating the convergence of the algorithm to the global optimal solution(Gbest).Subsequently,the superiority of GLSDMO is verified on CEC2017 and CEC2019,and the optimization effect of GLSDMO is analyzed in *** results show that GLSDMO is significantly superior to the compared algorithms in solution quality,robustness and global convergence rate on most test ***,the optimization performance of GLSDMO is verified on three classic engineering examples and one truss topology optimization *** simulation results show that GLSDMO achieves optimal costs on these real-world engineering problems.

关键词： Dwarf mongoose optimization algorithm Gbest-guided Lévy flight Adaptive parameter Salp swarm algorithm Engineering optimization Truss topological optimization

Development of Junction Elements from Study of the Bionics

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Journal of Bionic Engineering 2007年第1期4卷 41-46页

作者： Wilson Kindlein Junior Luis Henrique Alves Cndido André Canal Marques Sandra Souza dos Santos Maurício da Silva Viegas Laboratory of Design and Material Selection-LdSM-Materials department (DEMAT) School of Engineering–EE Federal University of Rio Grande do Sul-Brazil-UFRGS Brazil

The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in reference to the effectiveness of product dismount aiming the reduction of ambient impact in all its phases of use. The creation, the development and the confection of new junction elements were described, and case studies of new products developed specifically with this purpose were presented.

关键词： bionics Ecodesign junction elements

Resource Allocation for Channel Estimation in Reconfigurable Intelligent Surface-Aided Multi-Cell Networks

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Journal of Communications and Information Networks 2024年第1期9卷 64-79页

作者： Yining Xu Sheng Zhou department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua UniversityBeijing 100084China

Reconfigurable intelligent surface(RIS)is a promising solution to deal with the blockage-sensitivity of millimeter wave band and reduce the high energy consumption caused by network densification. However, deploying large scale RISs may not bring expected performance gain due to significant channel estimation overhead and non-negligible reflected *** this paper,we derive the analytical expressions of the coverage probability, area spectrum efficiency(ASE)and energy efficiency (ee)of a downlink RIS-aided multi-cell *** order to optimize the network performance, we investigate the conditions for the optimal number of training symbols of each antenna-to-antenna and antenna-to-element path (referred to as the optimal unit training overhead) in channel *** study shows that:1)RIS deployment is not“the more, the better”, only when blockage objects are dense should one deploy more RISs;2) the coverage probability is maximized when the unit training overhead is designed as large as possible;3)however,the ASE-and-ee-optimal unit training overhead exists. It is a monotonically increasing function of the frame length and a monotonically decreasing function of the average signal-to-noise-ratio (in the high signal-to-noise-ratio region). Additionally,the optimal unit training overhead is smaller when communication nodes deploy particularly few or many antennas.

关键词： reconfigurable intelligent surface multi-cell network directional transmissions channel estimation resource allocation stochastic geometry

Performance Analysis of Round Robin Scheduling for Session-based Applications on Clusters

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微计算机信息 2007年第24期23卷 181-183页

作者： CHEN YAN XU GUOZHI ee department Shanghai Jiaotong University Shanghai200240 China

Nowadays session-based applications are one of the typical applications in the Internet,and people build such applications on clusters on concern of scalability. Scheduling in such a cluster is a key technology since system performance depends on it. In this paper,we investigate the Round-Robin algorithm in the context of Session-based applications. An analyzing model for such sys-tems is proposed. Through both theoretical analysis and simulation,we find the main factor for system performance. And the result also shows that this algorithm shows up with significantly different performance under various conditions.

关键词：调度网页申请机群计算方法

Dynamic kinetic stereodivergent transformations of propargylic ammonium salts via dual nickel and copper catalysis

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Chinese Chemical Letters 2024年第8期35卷 265-269页

作者： Ruilong Geng Lingzi Peng Chang Guo Hefei National Laboratory for Physical Sciences at the Microscale and department of Chemistry University of Science and Technology of ChinaHefei 230026China

The dynamic kinetic asymmetric transformation of racemic propargylic ammonium salts with prochiral aldimine esters through a stereodivergent propargylation is catalyzed by dual nickel and copper ***,a diverse range of optically activeα-quaternary amino esters were produced via C-N bond cleavage with high reaction efficiency and stereoselectivity(up to>99%ee).By selection of the appropriate pair-wise combination of catalyst configurational isomers,all four possible stereoisomers of the corresponding propargylation products are obtained in high yields with excellent regio-,diastereo-,and enantioselectiv-ities.

关键词： Stereodivergent propargylation Dual catalysis C-N bond cleavage Azaomethine ylides Internal propargylic ammonium salts Excellent stereoselectivity

Tag-Aware Recommender Systems:A State-of-the-Art Survey

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Journal of Computer Science & Technology 2011年第5期26卷 767-777页

作者：张子柯周涛张翼成 Institute of Information Economy Hangzhou Normal University Web Sciences Center University of Electronic Science and Technology department of Physics University of FribourgChemin du Mus'ee 1700 FribourgSwitzerland

In the past decade,Social Tagging Systems have attracted increasing attention from both physical and computer science *** the underlying structure and dynamics of tagging systems,many efforts have been addressed to unify tagging information to reveal user behaviors and preferences,extract the latent semantic relations among items,make recommendations,and so ***,this article summarizes recent progress about tag-aware recommender systems,emphasizing on the contributions from three mainstream perspectives and approaches：network-based methods,tensor-based methods,and the topic-based ***,we outline some other tag-related studies and future challenges of tag-aware recommendation algorithms.

关键词： social tagging systems tag-aware recommendation network-based/tensor-based/topic-based methods

A novel scrape-applied method for the manufacture of the membrane-electrode assembly of the fuel-cell system

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Acta Mechanica Sinica 2009年第6期25卷 831-837页

作者： S. D. Wu C. P. Chou R. G. Peng C. H. Lee Y. Z. Wang department of Mechanical Engineering National Chiao Tung University EE412 1001 Ta Hsueh RoadHsinchu 30010 Taiwan China department of Chemical Engineering National YunlinUniversity of Science and Technology Yunlin China

This study investigates the transfer of the scrape-applied method from the electrodes of a lithium battery to the membrane-electrode assembly of fuel cells, including Proton Exchange Membrane Fuel Cells and Direct Methanol Fuel Cell. Three methods are commonly used to manufacture lithium battery electrodes： the roller-applied method, the spraying-applied method, and the scrape-applied method. This study develops novel scrape-applied equip- ment for lithium battery electrodes. This method is novel and suitable for producing fuel cell, better than other tradi- tional methods. In this study, the stability of coating process was tested by measuring the weight and thickness of a dry electrode. The stability and reproducibility of electrode fab- rication were examined by systematic data analysis. Finally, the study used a specially designed single cell composed of 16 conductive segments, which are insulated locally. The current passing through each segment was measured using Hall Effect sensors connected to the segment compartments. Based on the measured distribution of the local current in a segmented single cell, the influence of flooding and stoi- chiometry variation of feed gas was discussed in terms of electrochemical reaction rate. The experimental results serve as an important basis for future research in this field, which hold potential benefits to the academia and the industry.

关键词： Fuel cells . Scraper . Electrode. Lithium battery - Reliability

Amorphous Iridium Oxide-Integrated Anode Electrodes with Ultrahigh Material Utilization for Hydrogen Production at Industrial Current Densities

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Nano-Micro Letters 2024年第10期16卷 225-239页

作者： Lei Ding Kui Li Weitian Wang Zhiqiang Xie Shule Yu Haoran Yu David ACullen Alex Keane Kathy Ayers Christopher BCapuano Fangyuan Liu Pu-Xian Gao Feng-Yuan Zhang department of Mechanical Aerospace and Biomedical EngineeringUniversity of TennesseeKnoxvilleTN 37996USA Oak Ridge National Lab Center for Nanophase Materials SciencesOak RidgeTN 37831USA Nel Hydrogen WallingfordCT 06492USA Institute of Materials Science University of ConnecticutStorrsCT 06269USA department of Materials Science and Engineering University of ConnecticutStorrsCT 06269USA

Herein,ionomer-free amorphous iridium oxide(IrO_(x))thin electrodes are first developed as highly active anodes for proton exchange membrane electrolyzer cells(PEMECs)via low-cost,environmentally friendly,and easily scalable electrodeposition at room *** with a Nafion 117 membrane,the IrO_(x)-integrated electrode with an ultralow loading of 0.075 mg cm^(-2)delivers a high cell efficiency of about 90%,achieving more than 96%catalyst savings and 42-fold higher catalyst utilization compared to commercial catalyst-coated membrane(2 mg cm^(-2)).Additionally,the IrO_(x)electrode demonstrates superior performance,higher catalyst utilization and significantly simplified fabrication with easy scalability compared with the most previously reported ***,the remarkable performance could be mainly due to the amorphous phase property,sufficient Ir^(3+)content,and rich surface hydroxide groups in ***,due to the high activity,high cell efficiency,an economical,greatly simplified and easily scalable fabrication process,and ultrahigh material utilization,the IrO_(x)electrode shows great potential to be applied in industry and accelerates the commercialization of PEMECs and renewable energy evolution.

关键词： Ionomer-free Amorphous IrOx electrodes Ultrahigh material utilization Scalable electrodeposition Hydrogen production

Fast Arithmetics Using Chinese Remaindering

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China Communications 2007年第4期4卷 45-47页

作者： George Davida Bruce Litow department of ee & CS University of Wisconsin-MilwaukeeWIUSA School of Information Technology James Cook UniversityTownsvilleQLDAus-tralia

In this paper,some issues concerning the Chinese remaindering representation are discussed.A new converting method is described. An efficient refinement of the division algorithm of Chiu,Davida and Litow is given.

关键词： will NCI Fast Arithmetics Using Chinese Remaindering 一刀