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MAINTENANCE OF MULTI-STATE PRODUCTION SYSTEMS DETERIORATED BY RANDOM SHOCKS AND PRODUCTION

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Journal of Systems Science and Systems engineering 2011年第1期20卷 110-118页

作者： Won Seok YANG Dae E.LIM Kyung C.CHAE department of Business Administration Hannam University department of industrial and Systems engineering

We consider the preventive maintenance of a production system that is deteriorated by random shocks and the production process itself. The degree of deterioration is modeled by discrete and finite states. Shocks arrive according to a Poisson process and deteriorate the system by random amounts. The system may deteriorate whenever it produces an item. The system is continuously monitored and repaired if the system state is at or above a predetermined level for maintenance. We analyze the lifetime, product quantity, average cost, and average profit considering revenue from the product and cost due to setup, operation, and repair. Assuming a structure of system parameters and costs, using numerical examples, we investigate the impact of production and shock arrivals on the average profit and the optimal maintenance level that maximizes the average profit. The proposed model is applicable to manufacturing tasks in which machines wear due to production, for example, press processes, milling, turning, punching, and drilling.

关键词： Multi-state deterioration random shock maintenance cost-benefit analysis

Optimization of Honing Wheel Structure Parameters in Ultra-precision Plane Honing

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厦门大学学报（自然科学版） 2002年第S1期41卷 57-58页

作者： SYOJI Katsuo department of mechatronics and Precision engineering

Free abrasive particle machining in simple machine such as: honing, polishing can get higher surface finish mirror, but surface error, and working procedure is hard to control. Therefore, the vertical disposed ultra-precision plane honing method by ultra-particle diamond honing wheel is put forward to. The results of experiments indicate: plane-honing wheel has higher machining accuracy and machining efficiency. But at the same time the structure parameters of honing wheel effects on machining accuracy. By analyzing the relation of honing wheel structure parameters and workpiece machining accuracy, the relation of honing wheel and wear coefficient, then this paper gets honing wheel structure parameters in the condition of best accuracy coefficient and wear coefficient, and resolve the problem of choosing honing wheel structure parameters in ultra-precision plane honing at last. This paper analyses the relation of honing wheel structure parameters and workpiece machining accuracy coefficient and wear coefficient, by building relative movement math model of honing wheel and workpiece in plane honing. Through theory calculating, the result indicate: about honing machine tools for large volume manufacture, honing wheel wear is main effect factor, so honing wheel should adopt obverse triangle radial structure. About honing machining for high accuracy and low-batch quantities, machining accuracy coefficient is main factors; so honing wheel should adopt reverse triangle radial structure. Neglected the manufacturing factors of honing wheel, then we can design honing wheel with high power curve structure to meet the need of machining accuracy coefficient and honing wheel wear coefficient in higher accuracy honing.

关键词： ultra-precision plane honing honing wheel structure machining accuracy optimization parameters

Performance evaluation of waste electrical and electronic equipment disassembly layout configurations using simulation

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Frontiers of Environmental Science & engineering 2017年第5期11卷 65-75页

作者： Ozan Capraz Olcay Polat Askiner Gungor department of industrial engineering Naxmk Kemal University Corlu/Tekirdag 59860 Turkey department of industrial engineering Pamukkale University Pamukkale/Denizli 20160 Turkey

Recycling of waste electrical and electronic equipment （WEEE） is crucially important since it handles hazardous waste according to ever tightening laws and regulations and it adds benefits to economy and sustainable environment. Disassembly is one of the most important processes performed during the recovery of WEEE. The overall goal of disassembly is to maximize the retrieval of various metals and plastics contained in WEEE in order to reduce their negative effects on human health and environmental sustainability and to increase economic gains. This study aims to evaluate alternative layout configurations for WEEE disassembly systems （WDS）. In this context, various configurations were compared in terms of pre-defined performance criteria, such as the total number of disassembled WEEE and the total revenue from sales, using simulation models. The results of this study show that the perfomaance of a WDS was significantly affected by output transfer systems along with the specialization of operators on certain types of WEEE.

关键词： WEEE Recovery Disassembly Layout planning Simulation

Fabrication and shape detection of a catheter using fiber Bragg grating

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Advances in Manufacturing 2020年第1期8卷 107-118页

作者： Xiang-Yan Chen Ya-Nan Zhang Lin-Yong Shen Jin-Wu Qian Jia-Ying Fan department of mechatronics engineering and Automation Shanghai UniversityShanghai 200444People's Republic of China

Considering the spatial position and shape detection properties of the fiber Bragg grating(FBG)curve sensor used in the human body,the positioning accuracy of the FBG curve sensor plays a major role in the pre-diagnosis and treatment of *** present a new type of shape-sensing catheter(diameter of 2.0 mm and length of 810 mm)that is integrated with an array of four optical fibers,where each contains five nodes,to track the ***,the distribution of the four orthogonal fiber gratings is wound around a nitinol wire using novel packaging technology,and the spatial curve shape is rebuilt based on the positioning of discrete points in *** experimental platform is built,and then a reconstruction algorithm for coordinate point fitting of the Frenet frame is used to perform the reconstruction experiment on millimeter *** results show that,compared with those in previous studies,in 2D test,the maximum relative error for the end position is reduced to 2.74%,and in 3D reconstruction experiment,the maximum shape error is 3.43%,which verifies both the applicability of the sensor and the feasibility of the proposed *** results reported here will provide an academic foundation and the key technologies required for navigation and positioning of noninvasive and minimally invasive surgical robots,intelligent structural health detection,and search and rescue operations in debris.

关键词： Fiber Bragg grating(FBG) Thin diameter Encapsulation positioning Shape detection

Metal Flowing of Involute Spline Cold Roll-beating Forming

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Chinese Journal of Mechanical engineering 2013年第5期26卷 1056-1062页

作者： CUI Fengkui WANG Xiaoqiang ZHANG Fengshou XU Hongyu QUAN Jianhui LI Yan School of mechatronics engineering Henan University of Science and Technology department of Machinery and Precision Instrument engineering Xi’an Institute of Technology

The present research on involute spline cold roll-beating forming is mainly about the principles and motion relations of cold roll-beating,the theory of roller design,and the stress and strain field analysis of cold roll-beating,***,the research on law of metal flow in the forming process of involute spline cold roll-beating is *** to the principle of involute spline cold roll-beating,the contact model between the rollers and the spline shaft blank in the process of cold roll-beating forming is established,and the theoretical analysis of metal flow in the cold roll-beating deforming region is proceeded.A finite element model of the spline cold roll-beating process is established,the formation mechanism of the involute spline tooth profile in cold roll-beating forming process is studied,and the node flow tracks of the deformation area are *** experimental research on the metal flow of cold roll-beating spline is conducted,and the metallographic structure variation,grain characteristics and metal flow line of the different tooth profile area are *** experimental results show that the particle flow directions of the deformable bodies in cold roll-beating deformation area are determined by the minimum moving *** are five types of metal flow rules of the deforming region in the process of cold roll-beating *** characteristics of involute spline cold roll-beating forming are given,and the forming mechanism of involute spline cold roll-beating is *** paper researches the law of metal flow in the forming process of involute spline cold roll-beating,which provides theoretical supports for solving the tooth profile forming quality problem.

关键词： involute spline cold roll-beating forming rheological rule simulation

A new method for the fast simulation of models of highly dependable Markov system

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Science China(Technological Sciences) 2005年第1期48卷 23-30页

作者： XIAO Gang LI Zhizhong department of industrial engineering Tsinghua University Beijing 100084 China Department of Industrial Engineering Tsinghua University Beijing 100084 China

To fast evaluate the small probability that starts from the all-components-up state, the system hits the failed sets before returning to the all-components-up state, Important Sampling or Important Splitting is used commonly. In this paper, a new approach distinguished from Important Sampling and Important Splitting is presented to estimate this small probability of highly dependable Markov system. This new approach achieves variance reduction through improving the estimator itself. The new estimator is derived from the integral equation describing the state transitions of Markov system. That the variance of this estimator is less than that of naive simulation at all time is proved theoretically. Two example involved reliability models with deferred repair are used to compare the methods of RB, IGBS, SB-RBS, naive simulation, and the method presented in this paper. Results show our method has the least RE.

关键词： statistical estimator, variance reduction, dependability measures, Markov system, integral equation.

Mathematical Modeling of Carbon Content and Intercritical Annealing Temperature in DP Steels by Factorial Design Method

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Journal of Iron and Steel Research International 2014年第7期21卷 715-722页

作者： Gülcan TOKTAS Alaaddin TOKTAS Aslan Deniz KARAOGLAN department of Mechanical engineering Balikesir University department of industrial engineering Balikesir University

2k factorial design is employed to find the mathematical relation between the carbon content and intercritical annealing temperature （IAT） in order to predict the responses namely martensite volume fraction （MVF）, microhardness （H）, yield strength （YS）, ultimate tensile strength （UTS）, total elongation （TEL）, yield ratio （YR） and Charpy impact energy （CIE） in dual phase （DP） steels. Steels containing different carbon contents （0.085% C and 0.380% C） had been chosen for this purpose. The main advantages of factorial design are its easy implementation and the effective computation compared with the other optimization techniques, which were employed for predicting mentioned responses in the literature. To verify the proposed approach based on factorial design, experiments for verification were performed. The results of the verification experiments and the mathematical models are in accordance with each other and the literature.

关键词： dual phase steel factorial design material property prediction carbon content intercritical annealingtemperature

KIN SP:A boundary element method based code for single pile kinematic bending in layered soil

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Journal of Rock Mechanics and Geotechnical engineering 2018年第1期10卷 176-187页

作者： Stefano Stacul Nunziante Squeglia department of Civil and industrial engineering University of Pisa

In high seismicity areas, it is important to consider kinematic effects to properly design pile *** effects are due to the interaction between pile and soil deformations induced by seismic waves. One of the effect is the arise of significant strains in weak soils that induce bending moments on piles. These moments can be significant in presence of a high stiffness contrast in a soil deposit. The single pile kinematic interaction problem is generally solved with beam on dynamic Winkler foundation approaches(BDWF) or using continuous models. In this work, a new boundary element method(BEM)based computer code(KIN SP) is presented where the kinematic analysis is preceded by a free-field response analysis. The analysis results of this method, in terms of bending moments at the pile-head and at the interface of a two-layered soil, are influenced by many factors including the soil-pile interface discretization. A parametric study is presented with the aim to suggest the minimum number of boundary elements to guarantee the accuracy of a BEM solution, for typical pile-soil relative stiffness values as a function of the pile diameter, the location of the interface of a two-layered soil and of the stiffness contrast. KIN SP results have been compared with simplified solutions in literature and with those obtained using a quasi-three-dimensional(3D) finite element code.

关键词： Kinematic bending KIN SP Discretization Boundary element method(BEM) Pile-soil interaction Soil-structure interaction

Characterization of machine tools and measurement system for micromilling

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Nanotechnology and Precision engineering 2019年第1期2卷 23-28页

作者： Andrea Abeni Matteo Lancini Aldo Attansio department of Mechanical and industrial engineering University of Brescia

Technological progress has led to increased demand for small components with tiny features, which cannot be achieved through conventional machining. industrial application of processes based on microcutting is limited by some issues concerning the geometrical scale. The process performance is significantly affected by milling machine, tool holder, tool, workpiece material microstructure, workpiece fixtures, and process parameters. At present, an ultimate micromachining assessment procedure is not available. This study aims to propose and conduct an experiment on a testing procedure for micromilling. The set up to be implemented and the output to be considered are defined and described. Three major stages are identified: estimation of the effective bandwidth of the load cell–tool holder system, the milling machine natural frequency measurement, and micromilling test execution. The entire procedure is performed, and its robustness is demonstrated.

关键词： Micromilling Machine tool performance test Tool run-out Force analysis Modal analysis