Applied Mechanics and Materials Vols. 130-134

Abstract: Shot boundary detection (SBD) is the first step which segments video data into elementary shots for content-based video retrieval. In this paper, a shot boundary detection algorithm based on support vector machine (SVM) and particle swarm optimization (PSO) is proposed. First of all, the extracted features of pixel domain and compressed domain are combined to form a multi-dimension feature vector by using the scheme of sliding window. Next, particle swarm optimization with global search capacity is adopted to seek the approximately optimal parameters of radial basis function of SVM. Finally the model trained by the parameters obtained is applied to judge and categorize the frames into cut transitions, gradual transitions and non-transitions. The experimental results on the TREC video set 2001 demonstrate our algorithm is efficient and robust, and it solves the difficulty in parameter selection of SVM well.

Abstract: Freightcar’s running gear springs are easily ruptured in the processes of manufacturing and using, losing the role of relaxing vehicle vibration, and resulting in accident. It is time to study the automatic recognition of springs defects based on image processing technology. Defects recognition is on the premise of accurate spring image location. An image location algorithm for the freightcar’s running gear springs is proposed in this paper, which is based on the structure characteristics of springs themselves. The algorithm mainly includes graying the image, correcting non-uniform illumination by wavelet homomographic filtering, taking binaryzation on image based on the iterative threshold method and locating springs’ boundary location, which could be obtained by image scanning column by column and feature analysis. This algorithm can achieve the automatic positioning of springs and has a good result to locate springs in the running gear images in case of different illumination; the accuracy rate has reached 96 percent. The study of this paper lays a foundation on the realization of automatic recognition of springs defects and has good application prospects.

Abstract: Green machining is a process that implements sustainable development strategy. In order to reduce cost and decrease environmental pollution in manufacturing process, a sort of biodegradable castor oil-based emulsion is developed, whose physical and chemical properties can correspond with the national standards. The cooling and lubricating properties of the emulsion are better while machining steel materials through comparative experiments with certain imported commodity synthetic cutting fluid. The emulsion can successfully substitute for commodity fluid because of its high performance-price ratio.

Abstract: Aiming at the problems of coated carbide cutting tools used in Quenched 30crMnSiA steel milling such as poor cutting performance and shot service life.We have designed and produced a new type of PCBN tools as cutter head by welding. After high-speed milling and testing the Quenched 30CrMnsiA steel, we have optimized the process parameters and improved production efficiency. The experiment proved that the new type of PCBN tools can replace the carbide coated tools completely, It not only increases the tool life, but also reduces the tool costs, and fully demonstrated that the PCBN tools also have good application prospect in high-speed milling.

Abstract: The paper, based on the MIL-STD-1553B bus communication protocol, makes the computer-aided analysis to optimize bus transmission algorithm. An optimized algorithm is proposed by rearranging the commands set by the bus controller (BC), achieving the bus load balance in a major period. Through the command sequence optimization, this algorithm could manage the commands to be transmitted and generate an optimized bus command table. Based on the algorithm, software used in the PC is development, which could manage the commands to be transmitted, and generate optimized command table for bus communication transmission. The actual application shows that this algorithm can do well in optimizing the bus command table and improve the efficiency of bus transmission.

Abstract: The average reservoir pressure and water influx rate are two important parameters for reservoir with active bottom water. The paper, based on the model of KEITH, provides a solution by inversion of Laplace and Hankel, and obtains the relation between the average dimensionless reservoir pressure and water influx. If one is known, then the other can to be confirmed correctly. Compared with solution method of material balance, the affection of anisotropy is considered. In addition, sensitivity analysis of affecting factors on reservoir pressure is presented.

Abstract: Under the condition of MTO, delivery quantity models are studied, and five delivery modes are introduced. They are traditional delivery mode, equal quantity delivery mode, inventory delivery mode, ratio delivery mode and free delivery mode. Aiming at minimizing total cost of the delivery system, models based on five delivery modes are established. At last, a numerical exampleis conducted and the result shows that free delivery mode is better than other four delivery modes.

Abstract: We have demonstrated a method to monitor CD and first order PMD simultaneously of DPSK signal based on the RF spectrum analysis. The monitoring sensitivity can reach 56.7ps/nm/dB and 3.1ps/dB for CD and DGD, respectively.

Abstract: The COMPASS/Beidou Satellite Navigation System is no-blind zone for China and limited transmission capacity. It is critical for increasing the performance of disaster warning distribution by the COMPASS/Beidou system. By further analyzing the characteristics of transmission of COMPASS/Beidou, we find the method of solving that problem and also introduce some optimizations into the algorithm. The algorithm is based on application layer FEC to achieve the warning transmission probabilities. Simulation results show that the new scheme can efficiently be used disaster warning distribution system.

Abstract: This paper presents a Monte Carlo numeric simulation method application in reliability evaluation of exponential distribution. This method resolves reliability evaluation problem when test fault is zero. An example is given to illustrate this method is reliable and the result is reasonable.