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Chinese Journal of Electronics 2016年第3期25卷 495-502页

作者： YANG Hang LI Xunbo WANG Zhenlin yu wenjie HUANG Bo School of Communication and Information Engineering University of Electronic Science and Technology of China School of Mechatronics Engineering University of Electronic Science and Technology of China

A novel sensor deployment method utilize Discrete wavelet transform(DWT) is proposed, and the DWT is used to calculate the sub-band energy entropy to ascertain the coverage cavities in Wireless sensor networks(WSNs). We address the problem of deploying a limit number of sensors to optimize the coverage ratio in 3D surface, while it is a complex surface in space and sensors can be deployed only onto it. Another novel aspect of this paper is that the method followed utilizes an Artificial bee colony algorithm with dynamic search strategy(ABC-DSS), which mimics the behavior of bees, and the new modified ABC-DSS algorithm matches the sensor deployment problems on 3D surface well. The extensive simulations illustrate that comparing with the deployment method based on Particle swarm optimization(PSO) and ABC, the ABC-DSS which utilizes the wavelet sub-band energy entropy is functional and efficient on 3D surface deployment problems.

关键词： Artificial bee colony with dynamic search strategy(ABC-DSS) Discrete wavelet transform(DWT) Image processing Wireless sensor networks(WSNs)

Non-limit passive soil pressure on rigid retaining walls

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International Journal of Mining Science and Technology 2017年第3期27卷 581-587页

作者： Dou Guotao Xia Junwu yu wenjie yuan Fang Bai Weigang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining & Technology Xuzhou 221008 China Jiangsu Collaborative Innovation Center of Building Energy Saving and Construction Technology Xuzhou 221116 China Zhengzhou Zhongding Steel Structure Engineering Co. Ltd. Zhengzhou 450000 China

This paper aims to reveal the depth distribution law of non-limit passive soil pressure on rigid retaining wall that rotates about the top of the wall(rotation around the top(RT) model). Based on Coulomb theory, the disturbance degree theory, as well as the spring-element model, by setting the rotation angle of the wall as the disturbance parameter, we establish both a depth distribution function for sand and a nonlinear depth distribution calculation method for the non-limit passive soil pressure on a rigid retaining wall under the RT model, which is then compared with experiment. The results suggest that under the RT model: the non-limit soil pressure has a nonlinear distribution; the backfill disturbance degree and the lateral soil pressure increase with an increase in the wall rotation angle; and, the points where the resultant lateral soil pressure acts on the retaining wall are less than 2/3 of the height of the wall. The soil pressure predicted by the theoretical calculation put forward in this paper are quite similar to those obtained by the model experiment, which verifies the theoretical value, and the engineering guidance provided by the calculations are of significance.

关键词： RT model Rigid wall Non-limit passive soil pressure Spring element Genetic algorithm

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Three-dimensional numerical simulation for plastic injection-compression molding

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Frontiers of Mechanical Engineering 2018年第1期13卷 74-84页

作者： yun ZHANG wenjie yu Junjie LIANG Jianlin LANG Dequn LI State Key Laboratory of Material Processing and Die & MoldTechnology Huazhong University of Science and Technology Wuhan430074 China Beijing Institute of Aeronautical Materials Beijing 100095 China

Compared with conventional injection mold- ing, injection-compression molding can mold optical parts with higher precision and lower flow residual stress. However, the melt flow process in a closed cavity becomes more complex because of the moving cavity boundary during compression and the nonlinear problems caused by non-Newtonian polymer melt. In this study, a 3D simulation method was developed for injection-compres- sion molding. In this method, arbitrary Lagrangian- Eulerian was introduced to model the moving-boundary flow problem in the compression stage. The non-New- tonian characteristics and compressibility of the polymer melt were considered. The melt flow and pressure distribution in the cavity were investigated by using the proposed simulation method and compared with those of injection molding. Results reveal that the fountain flow effect becomes significant when the cavity thickness increases during compression. The back flow also plays an important role in the flow pattem and redistribution of cavity pressure. The discrepancy in pressures at different points along the flow path is complicated rather than monotonically decreased in injection molding.

关键词： injection-compression molding simulation,injection molding melt flow cavity pressure

Experimental and Numerical Research on Water Transport during Adsorption and Desorption in Cement-Based Materials

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1487-1507页

作者： Xiang Zhang Miao Su wenjie yu Zhen Lei Jun Ren Juntong Qu Department of Civil Engineering Yunnan UniversityKunming650091China School of Information Engineering Kunming UniversityKunming650214China

The durability of cement-based materials is related to water transport and storage in their pore network under different humidity *** understand the mechanism and characteristics of water adsorption and desorption processes from the microscopic scale,this study introduces different points of view for the pore space model generation and numerical simulation of water transport by considering the“ink-bottle”*** the basis of the pore structure parameters(i.e.,pore size distribution and porosity)of cement paste and mortar with water-binder ratios of 0.3,0.4 and 0.5 obtained via mercury intrusion porosimetry,randomly formed 3D pore space models are generated using two-phase transformation on Gaussian random fields and verified via image analysis method of mathematical *** the Kelvin-Laplace equation and the influence of“ink-bottle”pores,two numerical calculation scenarios based on mathematical morphology are proposed and applied to the generated model to simulate the adsorption-desorption *** simulated adsorption and desorption curves are close to those of the experiment,verifying the effectiveness of the developed model and *** obtained results characterize water transport in cement-based materials during the variation of relative humidity and further explain the hysteresis effect due to“ink-bottle”pores from the microscopic scale.

关键词： Cement-based material adsorption and desorption ink-bottle effect pore space modeling mathematical morphology

Harmonious Stock Prices

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Frontiers of Business Research in China 2014年第1期8卷 1-17页

作者： Hong Sun Jacqueline wenjie Wang Wayne yu Kai Zhu School of Accountancy Shanghai University of Finance and Economics Shanghai 200433China

Stock price movements in China still remain highly harmonious, in spite of the many significant regulatory and structural changes over the recent years. A survey of the literature reveals that harmony in the stock price movements is related to a few salient features in China＇s capital market： high ownership concentration, high incidence of the use of pyramidal ownership structure, significant state ownership, and a lack of active institutional investors. In addition, we also point out that harmonious stock prices may generally result from low intensity of private information acquisitions by risk arbitrageurs.

关键词： stock price synchronicity firm-specific information market efficiency

Debugging Strategies for Parents' Educational Anxiety in the Transition from Kindergarten to Primary School--Based on the Theory of Mature Forces

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教育技术与创新 2023年第4期5卷 59-70页

作者： wenjie yu Department of Preschool Education Wenzhou UniversityPR China

Due to the rapid growth of the economy and society,the burden of social security has been increasingly escalating,resulting in a continuous rise in parenting stress among certain groups of *** one hand,these parents aspire for their young children to grow through play;on the other hand,they are acutely aware that early childhood education constitutes the foundational stage of basic education and serves as the commencement phase of lifelong ***,they recognize the importance of emphasizing early childhood ***,preschool education has been given important *** place particular emphasis on education during this *** actively leverage their educational,financial,and social advantages to create favorable educational resources and opportunities for their young ***,to a certain extent,this exacerbates educational anxiety among a segment of *** the implementation of various governmental measures,it appears that these initiatives have not fundamentally addressed parental educational anxiety at its *** study employs interview techniques and literature review methodologies to gain a profound understanding of parental educational anxiety during the transition from early childhood to primary *** integrating Gesell's Maturation Theory,this research aims to scientifically explicate the developmental patterns of ***,it endeavors to enable non-professional parents to adopt a"professional"perspective in their approach towards early childhood education.

关键词： early childhood connection parental education anxiety mature force theory suggestion strategy

An Automatic Implementation of Oropharyngeal Swab Sampling for Diagnosing Respiratory Infectious Diseases via Soft Robotic End-Effectors

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 55-67页

作者： Yafeng Cui wenjie yu Jingjing Li Qi Shao Ding Weng Guoping Yin Xiaohao Zhang Xinjun Liu Jingying Ye Jiadao Wang Huichan Zhao Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Beijing Huakang Tongbang Technology Company Beijing 102609China Department of Otorhinolaryngology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Tianjin Research Institute for Advanced Equipment Tsinghua UniversityTianjin 300300China

The most widely adopted method for diagnosing respiratory infectious diseases is to conduct polymerase chain reaction(PCR)assays on patients’respiratory specimens,which are collected through either nasal or oropharyngeal *** manual swab sampling process poses a high risk to the examiner and may cause false-negative results owing to improper *** this paper,we propose a pneumatically actuated soft end-effector specifically designed to achieve all of the tasks involved in swab *** soft end-effector utilizes circumferential instability to ensure grasping stability,and exhibits several key properties,including high load-to-weight ratio,error tolerance,and variable swab-tip stiffness,leading to successful automatic robotic oropharyngeal swab sampling,from loosening and tightening the transport medium tube cap,holding the swab,and conducting sampling,to snapping off the swab tail and sterilizing *** an industrial collaborative robotic arm,we integrated the soft end-effector,force sensor,camera,lights,and remote-control stick,and developed a robotic oropharyngeal swab sampling *** this swab sampling system,we conducted oropharyngeal swab-sampling tests on 20 *** Digital PCR assay results(RNase P RNA gene absolute copy numbers for the samples)revealed that our system successfully collected sufficient numbers of cells from the pharyngeal wall for respiratory disease *** summary,we have developed a pharyngeal swab-sampling system based on an“enveloping”soft actuator,studied the sampling process,and imple-mented whole-process robotic oropharyngeal swab-sampling.

关键词： Diagnosis Medical robot Soft end-effector Swab-sampling Digital PCR

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Reconstructing proton channels via Zr-MOFs realizes highly ion-selective and proton-conductive SPEEK-based hybrid membrane for vanadium flow battery

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Journal of Energy Chemistry 2022年第12期75卷 448-456,I0012页

作者： Denghua Zhang wenjie yu yue Zhang Sihan Cheng Mingyu Zhu Shuai Zeng Xihao Zhang Yifan Zhang Chao Luan Zishen yu Lansong Liu Kaiyue Zhang Jianguo Liu Chuanwei Yan Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina

There is an urgent need to break through the trade-off between proton conductivity and ion selectivity of proton exchange membrane(PEM)in vanadium flow battery(VFB).Proton channels in PEM are the key to controlling the ion sieving and proton conductivity in ***,two types of proton channels are reconstructed in the hybrid membrane via introducing modified Zr-MOFs(IM-UIO-66-AS)into SPEEK *** proton channels in IM-UIO-66-AS and interfacial proton channels between grafted imidazole groups on Zr-MOFs and SPEEK greatly improve the conductivity of the IM-UIO-66-AS/SPEEK hybrid *** importantly,both reconstructed proton channels block the vanadium-ion permeation to realize enhanced ion selectivity according to the size sieving and Donnan exclusion effects,***,the hybrid membrane exhibits good mechanical property and dimensional *** from such rational design,a VFB loading with the optimized membrane exhibits enhanced voltage efficiency of 79.9%and outstanding energy efficiency of 79.6%at 200 m A cm^(-2),and keeps a notable cycle stability for 300 cycles in the long-term cycling ***,this study provides inspiration for preparing next-generation PEMs with high ion selectivity and proton conductivity for VFB application.

关键词： Vanadium flow battery Hybrid membrane Metal organic framework Proton channel Ion selectivity

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Traditional Chinese Crafts in the Context of Silk Road Civiization-Interview with Master Li Maodi,a Master of Zhuoni Tao Inkstone Making in Gansu's Zhuoni

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China Book International 2024年第2期 34-39页

作者： Li Maodi yu wenjie 不详 School of History Nanjing University

Professor yu wenjie:Master Li Maodi,the birth of Tao inkstones is closely linked to their geographical and historical *** would like to know what intellectual resources and cultural nourishment the Tao River culture provided to the formation and development of Tao ***,in recent years,the internationalization of ethnic crafts has become a new *** are curious about what new thoughts this modern living background has brought to you.

关键词： Master culture Gansu

Reactions of Tungsten Atoms with Hydrogen Sulfide:Matrix Infrared Spectra and Theoretical Calculations

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Reactions of Tungsten Atoms with Hydrogen Sulfide:Matrix Inf...