Abstract: In the multi-objective fuzzy decision-making system, the decision-making problems will be encountered in the multi-objective and multi-evaluation process, so that it does not achieve effective decision-making results. How to solve this multi-objective decision making problems, a fuzzy choice function is proposed, that will be proved an effective method of fuzzy evaluation. The multi-objective decision making problem in the selection and evaluation is effectively solved in a decision-making system by using of the fuzzy choice function.
Abstract: A new algorithm for the inverse kinematics of a kind of 6R serial robot was introduced. Firstly, the positions of all the joint points are determined with the help of the basic geometric entities, such as sphere, circle, line, plane and so on. Then, the angles of each joint are computed by the inner product between line and line or plane and plane. The proposed algorithm gives a new geometrically intuitive approach for solving the inverse kinematics of the robot.
Abstract: Networked munitions system is becoming more and more important with the development of modern electronic technology. This new generation of ground-based munitions are much more intelligent for the capability they have to trace targets, communicate with each other and order a killing node for vehicles caught in the kill-zone . It is useful to study and attempt to model through simulations the interaction between enemy targets and the whole munitions system . This paper is to propose a simulation-based model to study the performances of the weapon system. Especially, the sensors which sense the environment and the weapons which attack the targets are connected with wireless networks that will bring time delay to the system. We focus our efforts to evaluate how time delays from wireless communication affect the control performance of the weapon. This study introduces models for sensors and communication routing mechanisms , as well as the servo system and vehicle targets. A series of simulation trials to analyze and compare the effects of time delays have on the killing efficiency. The results of the study indicate in general that communication delay have the most effect on the systems.
Abstract: we discuss the problem of parameters recursive identification and designing of optimal input signal for minimum variance control from the point of system identification. we propose multi-innovation recursive least-squares identification method and separable iterative recursive least-squares identification method to identify and estimate it on line. Finally, the efficiency and possibility of the proposed strategy can be confirmed by the simulation example results.
Abstract: wafer processing is one process of the IC industry which is a booming area nowadays, the quality of the production of this course depends on the performance of the film which is formed by deposition. And one of the most important factors influencing the performance is working pressure. Variable structure chamber for flowing experiment and testing which is a multifunction testing platform with changeable structure and sufficient measurement points all-covered the chamber, a device has been designed and manufactured to measure and research vacuum flow filed. By using this equipment, the pressure in vacuum chamber could be measured precisely and promptly, thus relationships among the size and shape of the chamber, the pressure, and the gauges would be clear, there would be helpful for vacuum measurement.
The course of manufacturing a chip of IC production including 400~500 processes which could be divide into two categories: wafer processing which is FEOL (front-end-of-line) and chip packaging which is BEOL (back end of line), as it illustrated in Fig. 1. Wafer manufacturing is a process of exacting and refining high purity silicon (usually 99.999%) from silica; Wafer processing is depositing a thin film (among 100um to 22nm, according to the requirement and depending on technology) which contains required elements on the face of the original wafer; Dicing is chipping out wafer into little blockages to face different requirement; Assemble and packaging is fabricating chip into IC component.
During the course of Wafer processing, the working condition is usually under low velocity, high vacuum and high temperature condition (depends on the characteristics of sediment), take the project Deposition of Hydrogenated Amorphous Silicon as an example---- 5.0 sccm, 11.0~16.0 mtor, and 250°C. The performance of wafer is decided by the nature of reactors and the processing condition of which a little change would lead a different property of the production. Thus it is necessary and imperative to figure out the relationship among the factors influencing depositing process. And the most important among these factors are pressure, velocity, and temperature. In this paper, a method of pressure measurement based on a device of variable structure chamber for flowing experiment and testing will be introduced.
Fig. 1, Semiconductor manufacturing process
Abstract: In order to meet requirements of real-time dynamic navigation system, one multi-channels synchronization data acquisition system was designed based on PC104 bus. It can achieve simultaneous sampling of multiple channels data in one conversion cycle of ADC. The logic control is performed by FPGA, FIFO integrated by FPGA is used as buffer, so we can use resources of FPGA in large. At the same time, this design simplified the hardware circuit and improved circuit configuration flexibility. Using interrupt mode to read data into the FIFO, so it enhanced the data acquisition speed and reduced the burden on the navigation computer. Tests proved this system is efficient and feasible.
Abstract: Most measurement and control systems of combines use digital tubes or LCD as their monitor, which has some problems like low brightness, poor functional expansion and over-occupy port resources. In this paper, a signal acquisition and failure alarm system of combine harvester is designed, based on touch screen technology. The system uses MCU as the main control unit to receive forward speed signal and rotational speed signals of threshing cylinder, transport grain auger and conveyor pan. It handles the signal data, makes judgments, and sends the signal data to the touch screen through serial communication. Some functions like parameters display, parameters setting and faults alarm are set in the touch screen. The system is applied to Taihu Star TH988 combine harvester and had rice harvest tests. The results show that it has good human-computer interaction and improves stability and accuracy, hardware structure and electrical design simplified.
Abstract: To improve the dimension accuracy of integral stereolithography (SL) system, the resin liquid level in SL system need controlled. Based on the measuring principle of laser triangulation, a laser liquid level detection system for SL system has been developed. The laser liquid level detection system consists of light source, Position Sensitive Detectors (PSD), PSD signal processing circuit and data acquisition system. According to the principle that electrical signal of PSD changes when resin liquid level vary, a PSD is employed to detect the liquid level height in the liquid level detection system. Confirmation experiment is conduct to test the accuracy of the detection system, and the experiment results indicated that deviation is 0.34% in the range of 6mm, and satisfy the accuracy requirement of integral SL system.
Abstract: Phased array theory is analyzed. The PZT phased array is applied in SHM for the Al plate to identify the hole in the structure. The Lamb wave beam steering is controlled by adding the time delay to the signals. The structure can be scanned in half plane by using the phased array theory to control the Lamb wave beam steering. The damage in the structure can be recognized and localized by the phased array method. The identification result is shown on mapped image. The phased array damage localization method is verified by the experiment and the result shows that the method is effective to recognize the hole damage in the structure.