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Brain Cognition Mechanism-Inspired Hierarchical Navigation Method for Mobile Robots

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Journal of Bionic Engineering 2024年第2期21卷 852-865页

作者： Qiang Zou Chengdong Wu Ming Cong dong liu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110819China School of Mechanical Engineering Dalian University of TechnologyDalian116024China

Autonomous navigation is a fundamental problem in *** methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,traditional methods exist poor robustness and low cognitive *** a new navigation technology that draws inspiration from mammal’s navigation,bionic navigation method can map perceptual information into cognitive space,and have strong autonomy and environment *** improve the robot’s autonomous navigation ability,this paper proposes a cognitive map-based hierarchical navigation ***,the mammals’navigation-related grid cells and head direction cells are modeled to provide the robots with location *** then a global path planning strategy based on cognitive map is proposed,which can anticipate one preferred global path to the target with high efficiency and short ***,a hierarchical motion controlling method is proposed,with which the target navigation can be divided into several sub-target navigation,and the mobile robot can reach to these sub-targets with high confidence ***,some experiments are implemented,the results show that the proposed path planning method can avoid passing through obstacles and obtain one preferred global path to the target with high efficiency,and the time cost does not increase extremely with the increase of experience nodes *** motion controlling results show that the mobile robot can arrive at the target successfully only depending on its self-motion information,which is an effective attempt and reflects strong bionic properties.

关键词： Bionic navigation Spatial localization cells Global path planning Hierarchical motion controlling

Production of linear alkylbenzene over Ce containing Beta zeolites

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Chinese Journal of Chemical Engineering 2024年第3期67卷 220-227页

作者： Shiqi Zhang Shengzhi Gan Baoyu liu Jinxiang dong School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangzhou Key Laboratory of Clean Transportation Energy ChemistryGuangdong University of TechnologyGuangzhou 510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na *** citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta ***,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid *** addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene.

关键词： Beta zeolites Catalysis Alkylation Long-chain olefins

Method for triangular fuzzy multiple attribute decision making based on two-dimensional density operator method

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Journal of Systems Engineering and Electronics 2024年第1期35卷 178-185页

作者： LIN Youliang LI Wu liu Gang HUANG dong School of Economics and Management Hunan Institute of Science and TechnologyYueyang 414000China Hunan Vocational College for Nationalities Yueyang 414000China School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

Aiming at the triangular fuzzy(TF)multi-attribute decision making(MADM)problem with a preference for the distribution density of attribute(DDA),a decision making method with TF number two-dimensional density(TFTD)operator is proposed based on the density operator theory for the decision maker(DM).Firstly,a simple TF vector clustering method is proposed,which considers the feature of TF number and the geometric distance of ***,the least deviation sum of squares method is used in the program model to obtain the density weight ***,two TFTD operators are defined,and the MADM method based on the TFTD operator is ***,a numerical example is given to illustrate the superiority of this method,which can not only solve the TF MADM problem with a preference for the DDA but also help the DM make an overall comparison.

关键词： fuzzy decision making clustering density operator multi-attribute decision making(MADM)

Aging Mechanism and Life Estimation of Photovoltaic Inverter DC-link Capacitors in Alternating Humid and Thermal Environment

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Chinese Journal of Electrical Engineering 2024年第1期10卷 48-62页

作者： Quanyi Gao Shuaibing Li Yi Cui Yongqiang kang Haiying dong School of New Energy and Power Engineering Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Large Electric Drive System and Equipment Technology Tianshui 741000China School of Engineering University of Southern QueenslandSpringfield 4300Australia

DC-link capacitors play a vital role in managing ripple voltage and current in converters and various *** study focuses on exploring the aging characteristics of DC-link capacitors in alternating humid and thermal environments aligned with the operational conditions in photovoltaic and wind power *** to relevant power equipment standards,we designed a 24-h alternating humid and thermal aging environment tailored to the requirements of DC-link *** aging test platform is established,and 20 widely used metallized polypropylene film capacitors are selected for *** such as the capacitance,equivalent series resistance(ESR),and phase angle are assessed during aging,as well as the onset time and extent of aging at various *** study focuses on the aging mechanisms,analyzing electrode corrosion,the self-healing process,and dielectric *** the aging characteristics enabled us to calculate the lifespan of the capacitor and predict it under different degrees of capacitance *** results show that under alternating humid and thermal conditions,capacitance attenuation and ESR increase exhibit exponential nonlinearity,influenced by factors such as the oxidation and self-healing of capacitive metal electrodes,dielectric main-chain fracture,and crystal *** study underscores the pivotal role of encapsulation in determining the aging decay time.

关键词： DC-link capacitors aging mechanism life prediction metallized film capacitors

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： Li Yuchun Shen Chao liu Wei Li dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

An epidermal electrode based triboelectric walking energy harvester for wearable wireless sensing applications

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Science China(Technological Sciences) 2024年第3期67卷 949-957页

作者： CHANG ShiYuan liu FuHai CHEN JinKai XIA LianBin ZHOU Hao JIANG JingYang dong kang ZHANG ChenHao WU Yun CHEN Jin XUAN Weipeng SUN LingLing JIN Hao dong ShuRong LUO JiKui Ministry of Education Key Laboratory of RF Circuits and Systems Hangzhou Dianzi UniversityHangzhou 310018China Special Equipment College Hangzhou Vocational&Technical CollegeHangzhou 310018China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 330027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China

Harvesting bio-kinetic energy using a triboelectric nanogenerator(TENG) is one of the promising routes to solve the sustainable energy supply problem for wearable electronics. However, additional materials, complex fabricating processes or specific mechanical structures are needed for existing TENGs to harvest bio-kinetic energy. Besides, they need to be tightly attached to the human body, which may result in detachment and malfunction under tense human motion. Herein, an intrinsic epidermal electrode-based TENG(E-TENG) is proposed to harvest human walking energy. The wearing shoes and ground are used as tribo-materials, and the human epidermis is used as the back electrode of the E-TENG. Compared with the traditional TENGs,the E-TENG does not need any additional tribo-materials and complex mechanical structures. Under optimal conditions, the voltage output of E-TENG can reach 914 V. E-TENG has been used as a self-powered warning sensor and pedometer sensor for demonstration. Furthermore, E-TENG based self-powered wireless sensor system has been developed using a newly designed micro energy electronic switch(MEES). Ambient ultraviolet intensity, temperature and humidity information can be monitored and then transmitted to mobile phone every 3.5 min, demonstrating great potential for widespread wearable applications.

关键词： triboelectric nanogenerator wearable wireless sensing self-powered

Rockburst proneness considering energy characteristics and sample shape effects

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2441-2465页

作者： Song Luo Fengqiang Gong kang Peng Zhixiang liu School of Resources and Safety Engineering Central South UniversityChangsha410083China School of Civil Engineering Southeast UniversityNanjing211189China

Accurate prediction of rockburst proneness is one of challenges for assessing the rockburst risk and selecting effective control *** study aims to assess rockburst proneness by considering the energy characteristics and qualitative information during rock *** representative rock types in cylindrical and cuboidal sample shapes were tested under uniaxial compression conditions and the failure progress was detected by a high-speed *** far-field ejection mass ratio(FEMR)was determined considering the qualitative failure information of the rock *** peak-strength energy impact index and the residual elastic energy index were used to quantitatively evaluate the rockburst proneness of both cylindrical and cuboidal ***,the performance of these two indices was analyzed by comparing their estimates with the *** results show that the accuracy of the residual elastic energy index is significantly higher than that of the peak-strength energy impact *** residual elastic energy index and the FEMR are in good agreement for both cylindrical and cuboidal rock *** is because these two indices can essentially reflect the common energy release mechanism characterized by the mass,ejection velocity,and ejection distance of rock *** suggests that both the FEMR and the residual elastic energy index can be used to accurately measure the rockburst proneness of cylindrical and cuboidal samples based on uniaxial compression test.

关键词： Rockburst proneness Sample shape Strain energy Energy release Far-field ejection mass ratio(FEMR)

Planning an adaptive reuse development of underutilized urban underground infrastructures:A case study of Qingdao,China

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Underground Space 2024年第1期14卷 18-33页

作者： Yong-kang Qiao Fang-Le Peng Yun-Hao dong Chun-Fang Lu Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Urban underground infrastructures(UUIs)are a vital component of built capital for urban ***,many cities are now home to a multitude of disused or underutilized UUIs,not least aged purpose-built underground facilities,causing a waste of valuable underground space resource *** the process of urban renewal,adaptive reuse can be an attractive solution to breathe new life into underutilized UUIs,while addressing some of the modern problems of the built environment by an economically feasible ***,there is a prevalent absence in the current literature of the overarching planning and decision-making approaches for an adaptive reuse development of underutilized *** the intention of addressing this shortfall,this paper first lays out development strategies,then sets the generic patterns for adaptive reuse of disused or underutilized *** the city of Qingdao,China as a case study,detailed planning and decision-making approaches with the aid of multi-source data and spatial analysis tools are *** is anticipated that the findings of this research will assist the adaptive reuse development of UUIs in providing theoretical guidance and empirical evidence,thereby enhancing the role of urban underground space use in contributing to urban revitalization and urban sustainability.

关键词： Urban underground infrastructures Underutilized Adaptive reuse Planning Urban renewal

A systematic framework of constructing surrogate model for slider track peeling strength prediction

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Science China Technological Sciences 2024年第10期67卷 3261-3274页

作者： dong XingJian CHEN Qian liu WenBo WANG dong PENG ZhiKe MENG Guang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University KEIPER Seating Mechanisms Co. Ltd. Department of Industrial Engineering and Management Shanghai Jiao Tong University

Peeling strength can comprehensively reflect slider track safety and is crucial in car seat safety assessments. Current methods for determining slider peeling strength are primarily physical testing and numerical simulation. However, these methods encounter the potential challenges of high costs and overlong time consumption which have not been adequately addressed. Therefore, the efficient and low-cost surrogate model emerges as a promising solution. Nevertheless, currently used surrogate models suffer from inefficiencies and complexity in data sampling, lack of robustness in local model predictions, and isolation between data sampling and model prediction. To overcome these challenges, this paper aims to set up a systematic framework for slider track peeling strength prediction, including sensitivity analysis, dataset sampling, and model prediction. Specifically, the interpretable linear regression is performed to identify the sensitivity of various geometric variables to peeling strength. Based on the variable sensitivity, a distance metric is constructed to measure the disparity of different variable groups. Then, the sparsity-targeted sampling(STS) is proposed to formulate a representative dataset. Finally, the sequentially selected local weighted linear regression(SLWLR) is designed to achieve accurate track peeling strength prediction. Additionally, a quantitative cost assessment of the supplementary dataset is proposed by utilizing the minimum adjacent sample distance as a mediator. Experimental results validate the efficacy of sequential selection and the weighting mechanism in enhancing localization ***, the proposed SLWLR method surpasses similar approaches and other common surrogate methods in terms of prediction performance and data quantity requirements, achieving an average absolute error of 3.3 kN in the simulated test dataset.

关键词： slider track peeling strength surrogate model sensitivity analysis data sampling local weighted linear regression