Applied Mechanics and Materials Vols. 433-435

Abstract: In order to realize the performance testing and fault diagnosis of communication devices in the Command and Control System, a testing system is proposed. In this paper, a novel communication protocol is developed to realize the communication between the host computer and lower computer of the testing system. As to the different functions of the testing system, the format and sense of the communication messages were introduced in detail. 15 kinds of messages were designed to complete the functions of the open and close of communication serial, data detection ports, the receive and transmission of detection data, the control of the I/O and so on. The communication protocol makes it possible to form the test path and achieve the test of different devices.

Abstract: On the basis of previous work, this paper aims to build several proper drought indices based on the basic computation for the band information of passive microwave remote sensing AMSR-E data in Huaihe river basin. Compared with measured soil moisture, optimal drought indices have been selected to explore the spatio-temporal variation laws of drought conditions and its impact factors. The results indicate that there are satisfactory negative correlations between MPDIs (Microwave Polarization Difference Index) and observed soil moisture on the whole, which means the more negative the index is, the more serious the drought will be. Besides, MPDIs at frequency 69GHz and 187GHz calculated by AMSR-E brightness temperature data are much closer to the variation trend of soil moisture than those obtained from other bands.

Abstract: Soil moisture plays an important role in agricultural drought predicting. Hydrological models can be employed to forecast soil moisture. In order to get better predicted soil moisture information, we use two basin hydrological models, i.e. XXT and TOPMODEL, to forecast the soil moisture for Huaihe River watershed. The performance of both the two models was tested in the Linyi watershed with a drainage area of 10040 km², a tributary of the Huaihe river, China. The results show that the soil moisture simulated by the XXT is more agree with the observed ones than that simulated by TOPMODE compared to the filed observed soil moisture at 10 cm or the mean ones of 10 cm, 20 com, and 40 cm from surface, and that the predicted soil moisture by both the models has the similar trend and temporal change pattern with the observed one. However, both the models need to be improved in soil moisture forecasting in the future work.

Abstract: In the aerospace experimental task,rule based information quality analysis method is very useful not only to immediately discover the problem in information gathering,transporting and processing,but also to precisely evaluate the accomplish situation. Based on the data analyzing model and characteristic of the aerospace experimental tracking and control information ,the method constructed an information quality analysis rule framework that make real-time information quality analysis a reality by combining the rules in different manner on demand. As a result, the aerospace experiment tracking and control information can be dynamically monitored, and the abnormal data can be captured instantly to help estimating the system malfunction.

Abstract: The transformer fault diagnostic method based on Bayesian case library is proposed in the paper. Firstly, a transformer fault case library is established by collecting standard guideline and expert experience. Secondly, by standardizing the states and fault modes in the case library, the method takes the states as inputs and the fault modes as outputs, which are used to train a naive Bayesian network classifier. When it is necessary for a fault diagnosis, the user is expected to input the fault states in order to finalize the correct fault mode with the help of the well-trained classifier. On this basis, and with the details of the fault mode, the method could help to get the fault diagnosis results of the case. Finally, the feasibility and effectiveness of this developed method is illustrated by a numerical example of transformer fault diagnosis on site.

Abstract: In recent years, with the rapid development of smart grid, the harmonic monitoring has become an important part of electric energy quality control in smart grid. This paper introduced a method for real-time analysis of the harmonics with high precision, in which the FFT algorithm is used to convert the electrical signals from the time domain into the frequency domain to analyze the harmonics based on the TMS320F2812 processor. The experiment was conducted based on Code Composer Studio CCS3.3 and EVM board HDSP-Basic2812. The experiment simulation results were given in the paper.

Abstract: This paper studied the traditional supervisory control and data acquisition and investigates what is the most important in pipeline gas management system. Then a novel scheme is proposed for remote control interface on pipeline gas providing management. This scheme introduced GPRS and internet network technology to the traditional supervisory control and data acquisition. The details of System topological structure is given and Remote control interface structure are listed. At last, the system performance is analyzed and the results indicate that pipeline gas management system using remote control interface has the excellent protection performance and operability of RCI. It can meet the demand of intelligent home and intelligent building.

Abstract: Ultrasonic inspection is the most successful non-destructive testing technique for detection of flaws in engineering materials. Generally, discrete wavelet transform (DWT) is widely used to extract features for ultrasonic flaw signal. Directly taking the DWT coefficients as input vectors for training classifier, however, may result in computation complexity or even poor classification performanc. We propose a weighted linear discriminant analysis (WLDA) method to address the problem. In this study, DWT is first applied for the time-frequency analysis of ultrasonic flaw signals, and the wavelet coefficients are extracted as the initial features. After that, the proposed WLDA, which can effectively estimate the within-class and the between-class scatter through calculating similarity based weighting function, is used to reduce the dimension of original features. Finally, the features in new lower dimensional space are taken for flaw classification. Experimental results show that compared with the original and state of art linear discriminant analysis methods, WLDA is helpful for improving classification performance.

Abstract: There are so many problems in the traditional teaching practice, information technology teaching has fairly obvious advantages, information technology teaching with Internet as a carrier to spread, Web technology can achieve dynamic interaction, thus providing vivid, content-rich multimedia teaching as possible, in this paper, a system for the management of network teaching system are discussed and research.

Abstract: In order to improve flexibility and productivity of designing complex robot systems which consists of a number of sensors, actuators and processors for control, component-based design methodology is a key issue. Meanwhile, an FPGA (Field Programmable Gate Array) is a potential candidate for controlling real-time system like a robot, because it can achieve shorter response time and higher performance-power efficiency by its parallel processing of hardwired digital circuits. However, it is difficult to introduce an FPGA for robot systems because designing an FPGA requires implementation of the user application into a circuit using HDL (Hardware Description Language). In this paper, design and verification flow using a Java-to-HDL synthesizer (JavaRock) and a distributed object environment (ORB Engine) is proposed. A case study of designing an inverted pendulum robot system is described, which achieves below 10 us processing time for controlling the inverted pendulum system successfully within a small FPGA chip in battery operation.