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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 715-718页

作者：王洪福 school of Mechanical Engineering and automation North University of China

In order to produce the hear-resistant inner layer of hot-forging die, plasma spraying and plasma re-melting and plasma spray welding were adopted. Substrate material was W6Mo5Cr4V2. including 10%, 2.%, 30% SiC ceramic powder used as coating material to obtain different Ni-based SiC alloys coating. Micro-structure and micro-hardness analysis of the coating layer were followed, as well as thermophysical properties for the coating layer were measured. The experimental results show that the coating prepared with 70% Ni60, 30% SiC powder has best properties with plasma spray welding, in which the micro-hardness can achieve 1100 HV, meanwhile can improve the thermal property of hot-forging die dramatically.

关键词： hot forging die plasma spraying plasma re-melting plasma spray welding thermo- physical properties

Segregation of Molten Salt on Chromizing in Thermal Diffusion Process

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1189-1192页

作者：王洪福 school of Mechanical Engineering and automation North University of China

The segregation of thermal diffusion salt bath chromizing process was analyzed. The experimental chromizing ingredients were prepared by the four groups A, B, C, and D. In order to study the segregation status of this case, the cooling molten salt in the crucible was removed by drilling from the heart core of molten salt. The core of molten salt was analyzed by X-ray fluorescence spectroscopy and XRD. Through the analysis, we can conclude that the Cr element deposited in the bottom was 4.51 times than the top. Chloride added to the molten salt will reduce segregation. Meantime we proposed some measures to overcome the segregation problem.

关键词： segregation thermal diffusion process chromizing

Relationship between the Corrosion and Cr-Ni Content of Stainless Steel in Borax Bath

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1137-1139页

作者：王俊元 school of Mechanical Engineering and automation North University of China

The corrosion of stainless steel was experimentally investigated and analyzed to improve the service-life of the crucible and fixture clamps. Through the experiment, stainless steel was found to satisfy the crucible and fixture clamps materials. As the chromium element mass percentage of the stainless steel increased, the corrosion decreased rapidly at first and then slowly increased. With the corrosion time prolonging, the corrosion growth rate is generally a downward trend. With Chromium 2.%, the corrosive were the least. With Nickel element mass percentage increased, the corrosion increased rapidly at first and then decreased rapidly, flatten at the last. It was special that the corrosion had little relationship with the Chromium and Nickel mass percentage when the Nickel percentage is more than 35%. The most remarkable corrosion is corresponding with the Nickel element 12., the least corrosion with Nickel element 80%. So Nickel element 35% is the most optional.

关键词： corrosion chromium nickel stainless steel borax bath

International Transferring Trend in Manufacturing Industry

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厦门大学学报（自然科学版） 2002年第S1期41卷 222-223页

作者： ZHAO Xin-jun 1, XU Li-hui 2.(1. school of Mechanical Engineering and automation, Northeastern Unive rsity, Shenyang 110004, {2. 2. school of Business Administration, Northea stern University, Shenyang 110004, {2.)

This paper addressed the international transferring t endency of manufacturing industry one by one as follows: (1) The developed count ries realize manufacturing industry structure upgrade reling on worldwide tr ansference not only domestic transference. On one hand, the TNCs make cross-inv estments, transnational merger & acquisition so as to achieve the optimum colloc ation of R&D resources, and obtain innovation in knowledge and technology. On th e other hand, the developed countries transfer labor and resource intensive indu stry as well as the labor-intensive link of the production chain in highly tech nology industry to the developing countries, to make their industrial structure escalation. (2. The adjustment and upgrade of manufacturing industry presents "m ulti-step type". First, the object of international transference substitutes th e capital-intensive industry and maturing industry with complicate technique fo r the industry with labor-intensive, simple technique or higher pollution, or s ubstitutes non-core complex technological procedure and parts and components fo r assembly in manufacturing process. Secondly, technology transference forms "br ain-hand and foot" pattern, i.e. the developed countries are increasingly p aying more and more attention to the research and control of core technology, th us transferring simple technique and labor-intensive procedure in higher scienc e and technology. Thirdly, the developed countries begins to transfer both capit al and technology intensive production, as well as transfer certain procedures i n higher technology production process to a few developing countries, even t o transfer parts of R & D to developing countries. (3) TNCs promote the global m anufacturing network (GMN) by recombination and transfer. TNCs organize producti on, trade, technological research and transference through foreign direct invest ment (FDI) all over the world, as a result, GMN makes the national competence no longer depend on absolu

关键词： manufacturing industry international transferrin g tendency

New type of adaptive control for a class of distributed time-delay systems with adaptation regard to delay parameter

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Journal of Systems Engineering and Electronics 2010年第6期21卷 1054-1062页

作者： Lin Chai1, 2. Shumin Fei1, 2. Haiyan Jin1, 2. Ruimin Wang1, 2. and Yanhong Li1, 2.1. Key Laboratory of Measurement and Control of Complex Systems of Engineering, Southeast University, Nanjing 2.0096, P. R. china 2. school of {2., Southeast University, Nanjing 2.0096, P. R. china Key Laboratory of Measurement and Control of Complex Systems of Engineering Southeast UniversityNanjing 210096P.R.China school of automation Southeast UniversityNanjing 210096P.R.China

The problem on stabilization for the system with distributed delays is researched. The distributed time-delay under consideration is assumed to be a constant time-delay, but not known exactly. A design method is proposed for a memory proportional and integral （PI） feedback controller with adaptation to distributed time-delay. The feedback controller with memory simultaneously contains the current state and the past distributed information of the addressed systems. The design for adaptation law to distributed delay is very concise. The controller can be derived by solving a set of linear matrix inequalities （LMIs）. Two numerical examples are given to illustrate the effectiveness of the design method.

关键词： distributed delay linear matrix inequality (LMI) adaptive control time-delay systems memory PI feedback.

Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science china(Technological Sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2. WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of automation, Chinese Academy of Sciences, Shenyang 110016, china 2. Graduate {2., Chinese Academy of Sciences, Beijing 100039, china Correspondence should be addressed to Jing Xingjian 1. Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences 10016 Shenyang China 2. Graduate school Chinese Academy of Sciences 10039 Beijing China

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robot’s dynamic constraints. The direction of the coordinating force can be determiend on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2.and Jie Chen 2.3 1.Department of automation,Tsinghua University,Beijing 100084,P.R.china 2.{2. of automation,Beijing Institute of Technology,Beijing 100081,P.R.china 3.Complex System Intelligent Control and Decision,Ministry of Education,Beijing 100081,P.R.china Department of automation Tsinghua University Beijing 100084 P. R. China school of automation Beijing Institute of Technology Beijing 100081 P. R. China school of automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent Control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

关键词： timeliness efficacy function space-based informationsystem simulation system.

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2. Meng Ya3 and Meng Dazhi2.1. National Laboratory of Pattern Recognition,Institute of automation, Chinese Academy of Sciences, Beijing 100080, china 2. College of Applied Sciences, Beijing University of Technology, Beijing 10002., china 3. school of Science, Beijing Institute of Technology, Beijing 100081, china) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China school of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3, XIAO Hui1, RAO Li-min1 (1. school of Nuclear Engineering and Technology, East china Institute of Technology, Fuzhou 344000, Jiangxi, china 2. school of Mechanical Engineering and automation, Northeastern University, Shenyang 110004, Liaoning, china 3. school of Civil and Environmental Engineering, East china Institute of Technology, Fuzhou 344000, Jiangxi, china) [a] school of Nuclear Engineering and Technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] school of Mechanical Engineering and automation Northeastern University Shenyang 110004 Liaoning China [c] school of Civil and Environmental Engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2. ZHAO Ming-yang 2.(1. Graduate school of the Chinese Academy of Sciences, Beijing 100039 , china 2. Robotics Laboratory, Shenyang Institute of {2., Chinese Academy of S ciences, Shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. Researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control