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Improved Harris Hawks Algorithm and Its Application in Feature Selection

Computers, Materials and Continua 2024年第1期81卷 1251-1273页

作者： Zhang q. Li Y. Zhan J. chen S. School of Computer Science and Information Engineering Harbin Normal University Harbin 150025 China College of Systems Engineering National University of Defense Technology Changsha 410073 China

This research focuses on improving the Harris' Hawks Optimization algorithm (HHO) by tackling several of its shortcomings, including insufficient population diversity, an imbalance in exploration vs. exploitation, and a lack of thorough exploitation depth. To tackle these shortcomings, it proposes enhancements from three distinct perspectives: an initialization techniq.e for populations grounded in opposition-based learning, a strategy for updating escape energy factors to improve the eq.ilibrium between exploitation and exploration, and a comprehensive exploitation approach that utilizes variable neighborhood search along with mutation operators. The effectiveness of the Improved Harris Hawks Optimization algorithm (IHHO) is assessed by comparing it to five leading algorithms across 23 benchmark test functions. Experimental findings indicate that the IHHO surpasses several contemporary algorithms its problem-solving capabilities. Additionally, this paper introduces a feature selection method leveraging the IHHOalgorithm(IHHO-FS) to address challenges such as lowefficiency in feature selection and high computational costs (time to find the optimal feature combination and model response time) associated with high-dimensional datasets. Comparative analyses between IHHO-FS and six other advanced feature selection methods are conducted across eight datasets. The results demonstrate that IHHO-FS significantly reduces the computational costs associated with classification models by lowering data dimensionality, while also enhancing the efficiency of feature selection. Furthermore, IHHO-FS shows strong competitiveness relative to numerous algorithms. © 2024 The Authors. Published by Tech Science Press.

关键词： deep exploitation strategy energy factor update strategy feature selection HHO IHHO population diversity

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IMPLEMENTATION OF AUTOMATIC PROGRAMMING SYSTEM FOR SELECTIVE ELECTIVE LASER SINTERING OF RAPID PROTYPING

IMPLEMENTATION OF AUTOMATIC PROGRAMMING SYSTEM FOR SELECTIVE...

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The Eighth World Conference on Integrated Design & Process Technology

作者： q. chen1 A. Xu2 Y. Liu3 Y. Wei1 1College of Mechanical and Electronic Engineering Heibei University of Science and Technology Shijiazhuang P.R. China School of Mechanical 2 Engineering Hebei University of Technology Tianjin P.R. China 3Deprtment. of Mechanical Engineering Tianjin University of Technology. & Education Tianjin P.R. China

An automatic programming system for Selective Laser Sintering (SLS) of rapid prototyping isdescribed in detail. With the aid of Visual C++ and development kit of ObjectARX in MDT, theinterior informat

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Estimating Critical Clearing Time of Grid Faults Using DA of State-Reduction Model of Power Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 807-820页

作者： Yang Liu Zhongyang chen Huanjin Yao Lin Yi q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China China Southern Power Grid Research Institute Guangzhou 510663China

This paper proposes a critical clearing time (CCT) estimation method by the domain of attraction (DA) of a state-reduction model of power systems using sum of sq.ares (SOS) programming. By exploiting the property of the Jacobian matrix and the structure of the boundary of the DA, it is found the DA of the state-reduction model and that of the full model of a power system are topological isomorphism. There are one-to-one correspondence relationships between the number of eq.ilibrium points, the type of eq.ilibrium points, and solutions of the two system models. Based on these findings, an expanding interior algorithm is proposed with SOS programming to estimate the DA of the state-reduction model. State trajectories of the full model can be transformed to those of the state-reduction model by orthogonal or eq.iradius projection. In this way, CCT of a grid fault is estimated with the DA of the state-reduction model. The calculational burden of SOS programming in the DA estimation using the state-reduction model is rather small compared with using the full model. Simulation results show the proposed expanding interior algorithm is able to provide a tight estimation of DA of power systems with higher accuracy and lower time costs.

关键词： Critical clearing time domain of attraction expanding interior algorithm state-reduction model SOS programming

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Network Embedding Algorithm for Vulnerability Assessment of Power Transmission Lines Using Integrated Structure and Attribute Information

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 351-360页

作者： Xianglong Lian Tong q.an Zepeng Li Xingyu chen Wenhu Tang q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

In power systems,failures of vulnerable lines can trigger large-scale cascading failures,and vulnerability assessment is dedicated to locating these lines and reducing the risks of such *** on a structure and attribute network embedding(SANE)algorithm,a novel q.antitative vulnerability analysis method is proposed to identify vulnerable lines in this ***,a two-layered random walk network with topological and electrical properties of transmission lines is ***,based on the weighted degree of nodes in the two-layered network,the inter-layer and intra-layer walking transition probabilities are developed to obtain walk ***,a Word2Vec algorithm is applied to obtain lowdimension vectors representing transmission lines,according to obtained walk seq.ences for calculating the vulnerability index of transmissions ***,the proposed method is compared with three widely used methods in two test *** show the network embedding based method is superior to those comparison methods and can provide guidance for identifying vulnerable lines.

关键词： Network embedding random walk transmission lines vulnerability assessment

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Mechanical Behavior of Bamboo,and Its Biomimetic Composites and Structural Members:A Systematic Review

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Journal of Bionic Engineering 2024年第1期21卷 56-73页

作者： Shanyu Han Yuyuan He Hanzhou Ye Xueyong Ren Fuming chen Kewei Liu Sheldon q.Shi Ge Wang Institute of Biomaterials for Bamboo and Rattan Resources International Centre for Bamboo and RattanBeijing 100102China Key Laboratory of National Forestry and Grassland Administration/Beijing for Bamboo&Rattan Science and Technology Beijing 100102China National Forestry and Grassland Engineering Technology Center for Wood Resources Recycling College of Materials Science and TechnologyBeijing Forestry UniversityBeijing 100083China International Bamboo and Rattan Organization Beijing 100102China School of Civil Engineering Tsinghua UniversityBeijing 100084China Mechanical Engineering Department University of North TexasDentonTX 762077102USA

Bamboo is a typical biological material widely growing in nature with excellent physical and mechanical *** is lightweight with high strength and *** naturally optimized bamboo structure,which has inspired global material scientists and engineers for decades,is significantly important for the bionic design of novel structural materials with ultra-light,ultra-strong,or ultra-tough and comprehensive *** literature on innovative composite materials and structural members inspired by bamboo are reviewed in this paper,and the research progress and prospects in this field are expounded in three ***,the structural characteristics of the bamboo wall layer along the thickness and height directions are described in terms of chemical composition,gradient structure,pore structure,and hollow structure with variable ***,this paper summarizes the research progress on new composite materials and structural components by applying bamboo’s structural features from the perspective of sustainability,designability,and ***,given the limitations of current research,the biomimetic scientific research on bamboo’s structural characteristics is prospected from the interpretation of bamboo structure,new bamboo-like materials,and structural design optimization perspectives,providing a reference for future research on biomimetic aspects of biomass.

关键词： Bamboo Structural characteristics-Bamboo-like material Physical and mechanical properties

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Rational design of AgGaS/ZnS/ZnS q.antum dots with a near-unity photoluminescence q.antum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu Z.Z.Fu Y.Y.chen H.q.Dai Z.Hu W.L.Zhang R.q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS q.antum dots(q.s).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS q.s showed an excellent photoluminescence q.antum yield(PLq.)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLq. reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the q.s influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell q.s.

关键词： AgGaS q.antum dots Photoluminescence Core/shell Alloyed core/shell interface

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Screening for metabolic dysfunction-associated fatty liver disease:Time to discard the emperor’s clothes of normal liver enzymes?

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World Journal of Gastroenterology 2024年第22期30卷 2839-2842页

作者： chen-Xiao Huang Xiao-Dong Zhou Calvin q.Pan Ming-Hua Zheng Metabolic Dysfunction-Associated Fatty Liver Disease Research Center Department of HepatologyThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Department of Cardiovascular Medicine The Key Laboratory of Cardiovascular Diseases of WenzhouThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Division of Gastroenterology and Hepatology Department of MedicineNew York University Langone HealthNew York University Grossman School of MedicineNew YorkNY 11355United States Institute of Hepatology Wenzhou Medical UniversityKey Laboratory of Diagnosis and Treatment for the Development of Chronic Liver Disease in Zhejiang ProvinceWenzhou 325000Zhejiang ProvinceChina

Metabolic dysfunction-associated fatty liver disease(MAFLD)is the most prevalent chronic liver condition *** liver enzyme-based screening methods have limitations that may missed diagnoses and treatment *** chen et al,the risk of developing MAFLD remains elevated even when alanine aminotransferase levels fall within the normal ***,there is an urgent need for advanced diagnostic techniq.es and updated algorithms to enhance the accuracy of MAFLD diagnosis and enable early *** paper proposes two potential screening methods for identifying individuals who may be at risk of developing MAFLD:Lowering these thresholds and promoting the use of noninvasive liver fibrosis scores.

关键词： Metabolic dysfunction-associated fatty liver disease Non-alcoholic fatty liver disease Alanine aminotransferase Liver enzymes Screening Noninvasive liver fibrosis scores

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Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan q.Wang Y.chen W.B.Yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

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Precipitation transformation pathway and mechanical behavior of nanoprecipitation strengthened Fe-Mn-Al-C-Ni austenitic low-density steel

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Journal of Materials Science & Technology 2024年第7期174卷 157-167页

作者： Y.F.An X.P.chen L.Mei P.Ren D.Wei W.q.Cao College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Guangxi Engineering Research Center for Characteristic Metallic Powder Materials School of Electronic EngineeringGuangxi University of Science and TechnologyLiuzhou 545006China Central Iron&Steel Research Institute Beijing 100081China

Precipitation strengthening has been widely adopted in austenitic low-density steel owing to excellent hardened *** approach generally employs the coherentκ′carbides and non-coherent B2 *** the precipitation transformation pathway is decisive for further optimizing the microstructures under specific engineering ***,the detailed precipitation seq.ence of Fe-28Mn-11Al-1C-5Ni(wt%)austenitic low-density steel as well as its influence on mechanical prop-erties during aging process is systematically *** results reveal that nano-sizedκ′carbides domains(2 nm)exist in the solution-treated *** aging at 500℃for 1 h,the cuboidalκ′carbides(15-20 nm)uniformly disperse in austenite ***,after aging at 700℃for 15 min,the coarsenκ′carbides(30-35 nm)inhomogeneously distribute and align preferentially along the〈100〉***,extending the aging time to 60 min,the needle-type B2 particles replace theκ′carbides due to the enrichment of Ni elements at the phase boundaries among the austenite andκ′*** aging at 900℃,κ′carbides entirely dissolve into the austenite matrix,and the intragranular B2 particles are the sole precipitates in the austenite matrix and follow the K-S orientation relationship with *** work hardening capability seriously deteriorates due to the shearing ofκ′carbides by gliding *** the intragranular B2 particles preserve excellent work hardening rate by dislocations bow-out *** present work is meaningful for guiding the design of new generation dual-nano precipitation austenitic lightweight steel.

关键词： Lightweight steel κ′-carbides B2 particles Work hardening capability

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Experimental study of corner separation and unsteady characteristics in linear compressor cascades with and without sweeping jet actuator

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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： S.W.chen W.H.Li C.Xu q.H.Meng School of Energy Science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China

Sweeping jet actuator(SJA)has been widely applied for activeflow control in *** this paper,the SJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both SJA behaviors and SJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with SJA placed near the separation position,close to the endwall and under *** characteristic freq.encies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and SJA jets impact region helped to judge that SJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of SJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control Sweeping jet actuator Corner separation Oilflow visualization

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