Applied Mechanics and Materials Vols. 321-324

Abstract: Vacuum circuit breaker becomes more and more complicated, integrated, high-speed and intellectualized. To insure vacuum circuit breaker in its good conditions, the function of fault diagnosis gets more important than before in the process of repairing. This paper is addressed a model-based fault detection methodology for vacuum circuit breaker. At first, the dynamic model of vacuum circuit breaker is built. Secondly, DTW algorithm is introduced to compute the similarity value between the test data and the theoretical data. At last, the value comparison between the similarity and the threshold concludes whether a fault has occurred or the vacuum circuit breaker has potential hazardous effects. The experimental results show that this method is effective.

Abstract: The detecting distance is an important index, which is determined by many parameters. In the paper, the detecting distance is analyzed in the view of system, the detecting distance is simulated according to technical index of each part, and we can also calculate sending power of oscillator needed by detecting distance required.

Abstract: For the characteristics of all-weather monitoring and high accuracy, X-band radar develops into the new technical means of monitoring marine oil spill. This paper presents the principle, workflow and components of radar oil spill monitoring system, as well as its application in marine management and its development trend.

Abstract: The scheme based on soft redundancy and ZigBee is introduced due to the inadequacy of existing mine gas concentration monitoring system. The system is divided into underground and aerial parts. The gas concentration of mine working site can be tested automatically by underground part, which can transmit the data to the ground using ZigBee wireless communications technology. Two sets of identically configured PLC control system constitute the aerial part, which can meet redundancy requirements by procedures and directives. The solid technical support in mine safe operation can be provided based on the system, which improves the stability and reliability of the gas concentration monitoring.

Abstract: According to the real-time prediction for performance degradation trend, the commonly used method is just based on field data. But this methods prediction result will not be so much ideal when the fitting of degradation trend of field data is not good. To solve the problem, the paper introduces a new method which is not only based on field method but also based on reliability experimental data coming from the history experiment. We use the relationship between the field data and reliability experimental data to get the result of the two kinds of data respectively and then get the weights according to the two prediction results. Finally, the final real-time prediction result for performance degradation tendency can obtain by allocating the weights to the two prediction results.

Abstract: The traditional wired monitoring system for power plants is complex and hard to detect when the system faces some problems. The idea of monitoring the environment of power plants wirelessly is proposed to solve this problem. The feasibility of applying wireless sensor networks to power plants monitoring is analyzed. Then a wireless monitoring system based on XBee modules which are using ZigBee technology is designed. The temperature and electrical current data are gathered by sensors attached to the XBee modules and transferred to the PC controller through mesh network. An interface between coordinator and controller is designed utilized LABVIEW software to read data and send commands. In the end, a three nodes demo system is built up to testify the design.

Abstract: In order to find out the status of unmanned area and staff position in mine, the important content for intelligent mine is the detection and location of personnel underground. Analyze the architecture of location system and location principle based on Internet of Things (IoTs) along with ZigBee wireless networks and pyroelectric sensor technology. In the meantime, Install test wireless network nodes and achieve measurement data. The results show that this technique is suitable for the worse physical conditions in mine, lower in cost, higher accuracy in location and detection. The scheme can greatly improve the level of coal mine safety production and reduce the occurrence of catastrophes and casualties.

Abstract: To improve the accuracy and robustness of the moving object detection in the image sequence, the author improves the traditional algorithm which is based on the gray-value difference. The author makes good use of the color information of images and applies the pixels in red, green, blue the three component value as its identifying information. According to the background image color composition, it adapts and adjusts the proportion of the three groups. Dynamic threshold is used to do the binarization separation of the background difference image. The simulation experiment shows, this algorithm makes full use of the color features of image and achieve the expected goal of high recognizability and good robustness.

Abstract: The immigration is important in water resources and hydropower project. Using remote sensing and information technology is a significant means of improve performance. This paper sums up the status and demand of remote sensing application in immigration of water resources and hydropower project.

Abstract: An objective complexity evaluation method of electromagnetic environment is presented based on statistical characteristics analysis. In order to quantize variation characteristics and statistical law of electromagnetic environment, evaluation factors are introduced such as relative variation, average variational ratio, maximum variational ratio, standard deviation and skewness of power spectral density. Besides, evaluation factors such as time occupancy, spectrum occupancy, space occupancy and Average energy value are utilized to conduct the objective evaluation comprehensively and accurately in time, frequency, space and energy domains. The practicability of this method is validated by monitoring data. Results show that this method can effectively evaluate the complexity of electromagnetic environment.