Advanced Materials Research Vols. 328-330

Abstract: Reliving the stress of the urban public transport, the metro system is greatly superior to other transport methods on the load, energy consumption, mean drive speed, arrival on time and comfortableness. The passengers comfortable is the important part for developing the train operation strategies. For optimization of the energy, time saving and the passengers comfortableness during operation of the train, the proper objective function is designed. The train operation strategy for meeting the inter-stop passengers comfortableness at the curves was developed and the energy and time savings of the section were combined, and the optimization operation plan for the whole line was designed, to better meet the metro train operation.

Abstract: Internal vibration concrete shaping machine which has a wide application in construction industry was used to produce floor slab with round hole. According to market research and production practice, a new control system was designed to overcome the defects of existing internal vibration concrete shaping machine. This article focused on the new control system design, including driving scheme, control system selection and program design, etc. Debugging on-line, the running of this control system is normal, and the product quality is higher than before.

Abstract: The oil-gas-water three-phase flow experimental apparatus in key laboratory of process monitoring and control in Tianjin University is a set of indoor small experimental device, which can simulate oil wells, simulate the pipeline transport of multiphase flow and study the experiment of multiphase flow. The device includes energy power dynamic systems, measurement pipelines systems, multiphase flow test pipelines system, control valves, sampling and control system platform. The software of the control system is mixed programming between the configuration software MCGS and the Visual Basic.

Abstract: In order to remove noise in the broken wire signal of wire rope, a new denoising algorithm based on the correlation of inter scales wavelet coefficient was proposed. Because the wavelet coefficient of signal has strong correlation and the wavelet coefficient of noise does not has obvious correlation, in the process of calculating threshold, an inter scales correlation factor was constructed considering the part specialty of next scale on the same position after wavelet transform. The proposed factor can adaptively adjust threshold on the position of signal and noise, thereby otaining good denoising effect and holding the break information in original signal. The actual processing effect of simulation and damage signal of wire rope shows that the proposed method, compared with the classical threshold, not only effectively removes noise in original signal and improve the signal noise ratio(SNR),but also retains the break information of inspected damage signal of wire rope.

Abstract: The digital controller applied to the traveling system of the paving machine is researched in this paper. The software and hardware designs of the control system utilizing microcomputer are accomplished; the complete mathematical model of dynamic characteristics for whole drive system is also given out. A specific control strategy to control the machine’s running forwards and backwards of starting, braking, accelerating and decelerating is designed, and the control of turning right or left and steering is put out too. At the same time, when the PID theory is put into the design of the digital controller, the study of constant velocity control technology is emphasized greatly.

Abstract: An MCU based programmable frequency detector was developed and relative tests were carried out. The detector used few elements which are very common and cheap, one MCU which has only 8 pins and with small dimension, one Schimidt trigger, one D type flip-flop and several resistors and capacitors. Cost for the detector is very low. Besides hardware work, software program has played very important role in the detector. By adjusting program parameters, different frequency can be detected and detecting band width can also be adjusted. Program flow chart is given in this thesis. Test shows that the detector is stable and sensitive and is suitable for different applications, e.g. over power line data transmission, etc. This paper introduces theory of the detector, hardware design and the software programming.

Abstract: Being a fuel-saving technique, aerobraking has become increasingly popular in aeronautic industry and planetary exploration. It has been used in Mars missions by NASA.To realize aerobraking on Neptune, we started with the general situation, and obtained equations that can be universally applied based on fluid mechanics, celestial mechanics and kinematic. After captured by Neptune, the orbit of the spacecraft degenerates from the initial elliptical orbit to the final circular orbit due to many aerobraking passes through Neptune atmosphere. Based on the analysis about the general situation and reasonable assumptions, it was possible to calculate and describe the orbit after each time of aerobraking. Moreover, the relation between total durations and incidence angles was discussed based on the sensitivity and was fitted as a 6-order polynomial.

Abstract: In order to help the designer collect relative materials from expanding Internet, a product innovation design knowledge acquisition system based on MAS has been developed. Information on the Internet can be divided into structured data, non-structured data and semi-structured data, and two different acquisition processes from different sources were established. Based on aforementioned, the framework of the system was established with federal system of MAS. Layered structure feature was applied in each internal federal system. Finally, the development environment was selected, and three-tier B/S architecture was adopted. Each function modules with system were fulfilled by programming.

Abstract: A technique of feature extraction based on vibration phase diagram for roller of rolling mill was discussed. Basic theory of roller fault diagnosis based on vibration phase diagram was presented, causes for phase diagram under different conditions was analyzed and a method of computing the eigenvalue for distribution density matrix was provided. To same one roller vibration under identical environment, the cooperation of phase point probability distribution is only relelation to the density of probability distribution, and unconcerned with noise. It is also different to phase point distribution density of different states. A experiment was conducted on ψ500×2 shrewd roller of rolling mill, the feature of roller signal was extracted based on vibration phase diagram and chose Hidden Markov Model (HMM) to build and identify mould. The experiment shows that this system has better identification rate, and proves that this technique is effective.

Abstract: This paper aimed at the characteristics of the control system of baking in different period of tobacco leaf roasting process, intelligent control system of tobacco leaf roast control tactics based on fuzzy-PID is proposed. A designing method and Implementation algorithm of fuzzy-PID is given. For the difficulty of traditional PID controller parameters adjusting, the PID parameters were adjusted online by using fuzzy reasoning method. It can combine the advantages of general fuzzy control and traditional PID control in this method, and it is simulated and compared with general PID control on the simulation platform of MATLAB control box. The simulation results show that the fuzzy self-tuning PID controller has good dynamic response curve, short response time, small overmodulation, high steady state precision, and good dynamic and static performance by comparing with the traditional PID controller. Therefore temperature and humidity control of tobacco leaf roasting will perfectly improved by fuzz PID control.