Applied Mechanics and Materials Vols. 303-306

Abstract: This paper proposes a method calculating TTC and critical voltage using static power model based on real-time recording data, traditional power system dispatching calculation doesn’t consider load model, which does not agree with the real, this paper compares TTC and critical voltage under different load model and P-V curves, on which load model has a strong influence, so load modeling is necessary based on real-time data and is significant for improving system stability. The simulations show necessity and suitability of the method.

Abstract: Controlled and alternating induction magnetic field generation device which induces plant seeds to breed on floor space has been developed. The incentive ferrite induction coil is used in the device to produce induced magnetic field. The common AC-DC-AC topology was adopted for the variable frequency power supply, and AC power inverter circuit adopts SPWM inverter frequency modulation and voltage regulation mode, realizing the sinusoidal VVF. In order to improve the conversion efficiency of system electrical energy to magnetic energy, the RLC series resonant circuit is chosen in the circuit of output magnetic field. Measurement and control system using DSP microcomputer measurement and control technology and digital PID control method. The frequency and intensity of inductive magnetic field in the air gap changes as the changes of current intensity in coils. The experimental study of rice seeds shows that test result is obviously better than traditional biological magnetization induced breeding technique of fixed magnetic poles.

Abstract: Mine gas composition is complex, and its main component is methane (CH4), followed by carbon dioxide (CO2) and nitrogen (N2), also contains a small amount or trace amount of heavy hydrocarbon gases (ethane, propane, butane, pentane, etc.) , Hydrogen (H2), carbon monoxide (CO), sulfur dioxide (SO2), hydrogen sulfide (H2S) and so on. For gas detection, the gas compositions above with listed behind CH4 becomes its interference noise. A second harmonic modulation of the fiber laser was used to achieve low concentration of coal mine gas monitoring against a multi-component-gas background noise, and an early warning can be accomplished.

Abstract: This paper has put forward a decimal system based on binary system for representing figures of barcode image. Different with traditional distance of similar line unitary method, this paper invents the unitary decimalize method for EAN-13 image identification. Counting and sorting the times of the number that appears when scan the image to calculate the width of unit bar not use the averaging method, which has the same identification effect but more simple and effective. At last make the corresponding program to verify the method, the result shows this method performs well. It is not only suitable to the horizontal positive-going or reversed-going barcode image but also to the oblique barcode image.

Abstract: Boundary detection is very important in the size measurement of the turnout rail components using machine vision. A new algorithm about boundary detection based on machine vision system is proposed. First an improved median filtering algorithm was used to noise reduction an image. Second Gabor operator energy diagram is generated. Then an elliptical-butterfly surround inhibition was designed to suppress the textures and enhance the boundary. Last a new binarization method and boundary detection algorithm is put forward according to the human beings visual observation. Experimental results show that the algorithm has good feasibility and effectiveness.

Abstract: Design a real-time hydrological monitoring system. Using the ARM processor and video server combination of methods, realize the characteristic features of the next place machine extraction, and then through the GPRS connect PC . Also have the power supply, low power consumption, anti-interference characteristics. The system use Wince programming, to obtain the binary image, using morphological algorithm to remove useless characteristic features, then carries on the edge refinement, use the hough transform to extract the straight line equation of water level and the bank line to compute, can get out the distance between the two in the image, according to the actual coordinate can get the actual distance. The experimental results show that the system has a real time and efficiency, effectiveness, and other characteristics, get a good recognition effect.

Abstract: Error compensation can improve the accuracy of machine tools effectively. Among the error sources affecting the accuracy of CNC machine tool, geometric error is always set as a key performance criterion. This paper summarizes several methods of geometric error modeling and reviews the characteristics of different methods. Furthermore, available methods for measuring geometric errors have been reviewed also based on the advanced instruments. This work aims at enhancing the efficiency of error detection and give a perspective for the application of error compensation in the future.

Abstract: A new detection system has been designed and developed for detecting the contour size of automobile driver airbag. The detection system is mainly composed of a CCD camera, optical system and a computer which can implement image processing and image recognition. This system uses a CCD sensor as its sensitive element, as well as the basic principle of image processing combined with image segmentation and template matching to determine whether the contour size of airbag is qualified. The experimental results show that the system improves the detecting precision, and speed of assembling automobile airbags. It also solves the problems of a heavy workload by manual operations, inaccurate judgments and low efficiency.

Abstract: The AACMM is a kind of new coordinate measuring instrument based on non-Cartesian system. The errors of structure parameters are the main factors which affect the measuring accuracy, and the structural parameters identification can effectively improve the measuring accuracy of AACMM. The measuring model of an AACMM was established using the D-H method. Then the error model of the AACMM was established with total differential transforming method, from which the Jacobian matrix was obtained. The structure parameters’ errors which need to be identified through singular value decomposition of Jacobian matrix and the decomposition of orthogonal matrix elementary row transform can be determined. Finally, the least squares method was used in identifying the structure parameters’ errors of the AACMM, the results shows that the method proposed in this paper can identify the structure parameters efficiently.

Abstract: This paper describes the tension measurement performed on the suspenders on a self-anchored suspension bridge, Yulong Bridge, on the basis of measuring the natural frequencies of the suspenders in a free-damped vibration and subsequent calculation of the forces using simplified vibrating chord theory. The theoretical background and the practical and economic advantages of this method are discussed, as well as its most relevant limitations.