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Dispersion of the Mechanical Parts Performance Indicators Based on the Concept of Random Vector

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Chinese Journal of Mechanical engineering 2012年第1期25卷 153-159页

作者： XIA Changgao ZHU Pei ZHANG Meng GAO Xiang LU Liling school of Automobile and traffic engineering Jiangsu UniversityZhenjiang 212013China

To solve the precision and reliability problem of various machinery equipments and military vehicles, some military organisations, the industrial sector and the academia at home and abroad begin to pay attention to the statistical distribution of machining dimensions, material properties and service loads, and the system reliability optimization design with constraints and reliability optimization design of various mechanical parts is studied in this way. However, the above researches focus on solving the strength and the life problem, and no studies have been done on the discrete degree and discrete pattern of other performance indicators. The concept of using a random vector to describe the mechanical parts performance indicators is presented; characteristics between the value of the vector variance matrix determinant and the sum of the diagonal covariance matrix in describing the performance indicators of vector dispersion are studied and compared. A clutch diaphragm spring is set as an example, the geometric dimension indicator is described with random vector, and the applicability of using variance matrix determinant and variance matrix trace of geometric dimension vector to describe discrete degree of random vector is studied by using Monte-Carlo simulation method and component discrete degree perturbation method. Also, the effects of different components of diaphragm spring geometric dimension vector on the value of covariance matrix determinant and the sum of covariance matrix diagonal of diaphragm spring performance indicators vector are analyzed. The present study shows that the impacts of the dispersion of diaphragm spring cone angle on every performance dispersion are all ranked first, and far exceed that of other dimension dispersion. So it must be strictly controlled in the production process. The result of the research work provides a reference for the design of diaphragm spring, and also it presents a proper method for researching the performance of

关键词： diaphragm spring random vector dispersion

Adaptive current compensation with nonlinear disturbance observer for single-sided linear induction motor considering dynamic eddy-effect

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Journal of Central South University 2015年第5期22卷 1716-1724页

作者：邓江明陈特放陈春阳 school of Information Science and engineering Central South University school of traffic transportation and engineering Central South University

An adaptive current compensation control for a single-sided linear induction motor(SLIM) with nonlinear disturbance observer was developed. First, to maintain t-axis secondary component flux constant with consideration of the specially dynamic eddy-effect(DEE) of the SLIM, a instantaneously tracing compensation of m-axis current component was analyzed. Second,adaptive current compensation based on Taylor-discretization algorithm was proposed. Third, an effective kind of nonlinear disturbance observer(NDOB) was employed to estimate and compensate the undesired load vibrations, then the robustness of the control system could be guaranteed. Experimental verification of the feasibility of the proposed method for an SLIM control system was performed, and it showed that the proposed adaptive compensation scheme with NDOB could significantly promote speed dynamical response and minimize speed ripple under the conditions of external load coupled vibrations and unavoidable feedback control variables measured errors, i.e., current and speed.

关键词： single-sided linear induction motors(SLIMs) current compensation adaptive control dynamical response nonlinear disturbance observer(NDOB)

Threshold logic based low-level vision sparse object features

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International Journal of Intelligent Computing and Cybernetics 2016年第4期9卷 314-324页

作者： Nitha Thomas Joshin John Mathew Alex James Department of Research EnviewTrivandrumIndia ARS traffic and transport Technology TrivandrumIndia school of engineering Nazarbayev UniversityAstanaKazakhstan

Purpose-The real-time generation of feature descriptors for object recognition is a challenging *** this research,the purpose of this paper is to provide a hardware friendly framework to generate sparse features that can be useful for key feature point selection,feature extraction,and descriptor *** inspiration is drawn from feature formation processes of the human brain,taking into account the sparse,modular,and hierarchical processing of visual ***/methodology/approach-A sparse set of neurons referred as active neurons determines the feature points necessary for high-level vision applications such as object recognition.A psycho-physical mechanism of human low-level vision relates edge detection to noticeable local spatial stimuli,representing this set of active neurons.A cognitive memory cell array-based implementation of low-level vision is *** of memory cell in edge detection are used for realizing human vision inspired feature selection and leading to feature vector construction for high-level vision ***-True parallel architecture and faster response of cognitive circuits avoid time costly and redundant feature extraction *** of proposed feature vector toward high-level computer vision applications is demonstrated using standard object recognition *** comparison against existing state-of-the-art object recognition features and methods shows an accuracy of 97,95,69 percent for Columbia Object Image Library-100,ALOI,and PASCAL VOC 2007 databases indicating an increase from benchmark methods by 5,3 and 10 percent,***/value-A hardware friendly low-level sparse edge feature processing system isproposed for recognizing *** edge features are developed based on threshold logic of neurons,and the sparse selection of the features applies a modular and hierarchical processing inspired from the human neural system.

关键词： Object recognition Object features Sparse features Threshold logic Low-level vision Active neurons Cognitive memory-cell array Edge detection Feature description

Multi-Objective optimization for stable and efficient cargo transportation of partial space elevator

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Defence Technology(防务技术) 2025年第2期44卷 17-29页

作者： Gefei Shi Zheng H.Zhu school of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China Department of Mechanical engineering York University4700 Keele StreetTorontoCanada

This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration stability in cargo *** LD-ASF is further optimized for payload transportation efficiency by a novel coordinate game theory to balance competing control objectives among payload transport speed,stable end body's libration,and overall control input via model predictive *** transfer period is divided into several sections to reduce computational *** validity and efficacy of the proposed LD-ASF and coordinate game-based model predictive control are demonstrated by computer *** results reveal that the optimized LD-ASF results in higher transportation speed,stable end body's libration,lower thrust fuel consumption,and more flexible optimization space than the classic analytical speed function.

关键词： Partial space elevator Stable transportation Libration decoupling analytical speed function Coordinate game Model predictive control Pareto optimization

Metal-organic frameworks (MOFs) in aqueous batteries (ABs):unlocking potential through innovative materials design

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Science China Chemistry 2025年

作者： Bo Han Erhai Hu Bei-Er Jia Ziyang Liu Shuen Tso Afriyanti Sumboja Ivandini T.Anggraningrum Anne Zulfia Syahrial Qingyu Yan SCARCE Laboratory Energy Research Institute NTU (ERIN) Nanyang Technological University school of Materials Science and engineering Nanyang Technological University Material Science and engineering Research Group Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Department of Chemistry University of Indonesia Metallurgical & Materials engineering Department Fakultas Teknik Universitas Indonesia

Metal-organic frameworks (MOFs) represent a revolutionary class of materials in the field of energy storage,particularly for aqueous batteries (ABs).Distinguished by their large surface area,tuneable porosity,and adaptable chemical activity,MOFs offer significant advantages over conventional materials in battery *** article provides a thorough analysis of the crucial role that MOFs play in improving the efficiency of *** includes a concise review of the current research progress,emphasizing the fundamental processes by which MOFs enhance electrochemical ***,the review examines the synthesis and design strategies for the structure of MOFs to maximize ion transport,improve conductivity,and enhance *** structural advantages,chemical versatility,stability,durability and functionalization potential of MOFs are comprehensively ***,we explore the distinct advantages of MOFs in overcoming common challenges encountered in ABs,such as declining capacity,inadequate cycling stability,and limited energy *** paper also highlights the future research directions needed to fully harness their *** goal is to develop a fundamental understanding and stimulate further progress in the use of MOFs for advanced energy storage solutions.

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Vehicle Detection Based on Visual Saliency and Deep Sparse Convolution Hierarchical Model

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Chinese Journal of Mechanical engineering 2016年第4期29卷 765-772页

作者： CAI Yingfeng WANG Hai CHEN Xiaobo GAO Li CHEN Long Automotive engineering Research Institute Jiangsu University school of Automotive and traffic engineering Jiangsu University

Traditional vehicle detection algorithms use traverse search based vehicle candidate generation and hand crafted based classifier training for vehicle candidate *** types of methods generally have high processing times and low vehicle detection *** address this issue,a visual saliency and deep sparse convolution hierarchical model based vehicle detection algorithm is proposed.A visual saliency calculation is firstly used to generate a small vehicle candidate *** vehicle candidate sub images are then loaded into a sparse deep convolution hierarchical model with an SVM-based classifier to perform the final *** experimental results demonstrate that the proposed method is with 94.81% correct rate and 0.78% false detection rate on the existing datasets and the real road pictures captured by our group,which outperforms the existing state-of-the-art *** importantly,high discriminative multi-scale features are generated by deep sparse convolution network which has broad application prospects in target recognition in the field of intelligent vehicle.

关键词： vehicle detection visual saliency deep model convolution neural network

Fuzzy Sliding Mode Control for the Vehicle Height and Leveling Adjustment System of an Electronic Air Suspension

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Chinese Journal of Mechanical engineering 2018年第2期31卷 238-250页

作者： Xiao-Qiang Sun Ying-Feng Cai Chao-Chun Yuan Shao-Hua Wang Long Chen Automotive engineering Research Institute Jiangsu University school of Automotive and traffic engineering Jiangsu University

The accurate control for the vehicle height and leveling adjustment system of an electronic air suspension(EAS) still is a challenging problem that has not been effectively solved in prior researches. This paper proposes a new adaptive controller to control the vehicle height and to adjust the roll and pitch angles of the vehicle body(leveling control) during the vehicle height adjustment procedures by an EAS system. A nonlinear mechanism model of the full?car vehicle height adjustment system is established to reflect the system dynamic behaviors and to derive the system optimal control law. To deal with the nonlinear characters in the vehicle height and leveling adjustment processes, the nonlinear system model is globally linearized through the state feedback method. On this basis, a fuzzy sliding mode controller(FSMC) is designed to improve the control accuracy of the vehicle height adjustment and to reduce the peak values of the roll and pitch angles of the vehicle body. To verify the effectiveness of the proposed control method more accurately, the full?car EAS system model programmed using AMESim is also given. Then, the co?simulation study of the FSMC performance can be conducted. Finally, actual vehicle tests are performed with a city bus, and the test results illustrate that the vehicle height adjustment performance is effectively guaranteed by the FSMC, and the peak values of the roll and pitch angles of the vehicle body during the vehicle height adjustment procedures are also reduced significantly. This research proposes an effective control methodology for the vehicle height and leveling adjustment system of an EAS, which provides a favorable control performance for the system.

关键词： Electronic air suspension Height adjustment Leveling control Fuzzy sliding mode control Vehicle tests

Influence of Bionic Non-smooth Surface on Water Flow in Antiskid Tire Tread Pattern

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Journal of Donghua University(English Edition) 2013年第4期30卷 336-342页

作者：王国林周海超杨建梁晨金梁 school of Automotive and traffic engineering Jiangsu University

Inspired by the idea that bionic non-smooth surfaces(BNSS)can reduce water flow resistance,the application of BNSS resistance reduction method in grooves surface of antiskid tire tread pattern has been investigated for increasing hydroplaning velocity of tire by using computational fluid dynamics(CFD)*** kinds of BNSS(riblet,convex dome,and dimple concave)are arranged in tire tread grooves to study the water flow resistance effects in grooves with non-smooth characteristics.A tire-water coupled model is established and CFD technique is applied to simulating *** simulation results show that BNSS grooves can reduce water flow resistance and increase mean flow rate by disturbing the eddy movement in boundary *** drag forces of riblet and dimple surface are lower and drainage capacity is higher than those of smooth surface under the same void space on tread pattern,but it is not in *** is a good way to promote antiskid performance without increasing additional groove space;extra tire-road noise production is therefore avoided due to groove space enlargement.

关键词： bionic non-smooth drag reduction tire hydroplaningCLC number:U463.341 O35Document code:AArticle ID:1672-5220(2013)04-0336-07

Iron scrap derived nano zero-valent iron/biochar activated persulfate for p-arsanilic acid decontamination with coexisting microplastics

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Journal of Environmental Sciences 2025年第5期151卷 733-746页

作者： Zihan Shu Hailan Yang Shujing Ye Hong Li Zhiming Yang Chuang Li Xiaofei Tan Shaobo Liu Hou Wang College of Environmental Science and engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China Shenzhen Research Institute of Hunan University Shenzhen 518055China school of Resources Environment and MaterialsGuangxi UniversityNanning 530004China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China school of Architecture and Art Central South UniversityChangsha 410083China school of Metallurgy and Environment Central South UniversityChangsha 410083China

P-arsanilic acid(AA)has received widespread attention because of its conversion to more toxic inorganic arsenic compounds(arsenate and arsenite)in the natural *** removal process and mechanisms with co-existence of microplastics remain *** this study,biochar loaded with nano zero-valent iron(nZVI)particles(ISBC)was prepared by using iron scrap obtained from a steel works and wood chips collected from a wood processing *** advanced oxidation system of sodium persulfate(PDS)activated by ISBC was applied for AA degradation and inorganic arsenic control in aqueous *** than 99%of the AA was completely degraded by the ISBC/PDS system,and the As(III)on AA was almost completely oxidized to As(V)and finally removed by ***_(3)−inhibited the removal of AA by the ISBC/PDS system,while Cl^(−)had a dual effect that showing inhibition at low concentrations yet promotion at high *** effect of microplastics on the degradation of AA by the ISBC/PDS system was further investigated due to the potential for combined microplastic and organic arsenic contamination in rural/remote *** were found to have little effect on AA degradation in the ISBC/PDS system,while affect the transport of inorganic arsenic generated from AA ***,this study provides new insights and methods for efficient removal of p-arsanilic acid from water with coexisting microplastics.

关键词： P-arsanilic acid Biochar Arsenate and arsenite Microplastics