Applied Mechanics and Materials Vols. 303-306

Abstract: This article briefly elaborated the basic concepts of the probe vacillated at testing a large silicon wafer with square four point probe equipment. The importance of the micro-area’s sheet resistance is discussed and the basic principles of four point probe measurement technology are analyzed. Some factors that affect the measurement accuracy are studied, and interference can be avoided while measuring and analyzing the impact on square four point probe measurement by probe vacillate. The calculation formula of the square micro-area probe measurement is deduced when probes vacillated discretionarily. At last, an experiment was made with a small wafer sample and accurate resistivity was gotten.

Abstract: Quantum-behaved particle swarm optimization algorithm (QPSO) was proposed as a kind of swarm intelligence, which outperformed standard particle swarm optimization algorithm (PSO) in search ability. This paper presents an improved QPSO with nonlinear controlled parameter according to the fitness value of the particles. Simultaneously, we apply the improved QPSO to solve the problems of target position measurement. The experimental results show that the improved QPSO has faster convergence speed, higher measurement accuracy, and good localization performance.

Abstract: In the fault diagnosis systems, the measured value of a test is generally divided into several intervals to isolate the faults. Furthermore, in the realistic systems, the value may be distributed over different intervals with a probability if a fault occurs, which means that the tests are multi-outcome imperfect tests. In this paper, a calculation method of metrics of fault detection and fault isolation based on extended dependency matrix is proposed, which can be applied to evaluate the testability of a system and consequently play a role in the design process of diagnosis systems.

Abstract: The unmanned folding wing aircraft has the advantage on expanding the flight envelope. The angle measurement algorithm of folding wing craft which based on MEMS (micro-electromechanical systems) accelerometers was studied. Collected the acceleration values from the accelerometers, and built the motion parameter model .Used the analyze data and the redundant acceleration; multiple sensors were used to do the error correction. With the experiment of folding wing, the validity and accuracy of the algorithm was verified.

Abstract: Atmospheric path radiance is the key factor in the accuracy of objective radiation measurement. In the traditional radiation character measurements, under the help of the atmospheric observation equipment, MODTRAN and other software likewise, the indeterminacy rate could be around 10~20%, it is highly restricts the measurement accuracy of objective radiation. For this reason, it is quite significant to develop the study of measure and calculation in path radiance. The approximate calculation formula for path radiance in close range and horizontal direction is expressed in this article; it is compared with the results of MODTRAN and measurement in experiment. It is revealed that the accuracy of software is 7.8%, and the formula is 4.9%, which could demonstrate the validity of the approximate calculation formula in close range and horizontal direction. In this article, in the process of deducing and experiment, the validity of the approximate calculation formula in close range and horizontal direction is fully proved, which supply a new method in approximate calculation of path radiance for objective radiation measurement.

Abstract: Based on some at present advanced geophysical methods, a non-destructive detection method mainly depending on ground penetrating radar(GPR) has been established by combining with Rayleigh wave method and natural electrical field method. The quality of earth-fill dam not only can be evaluated and analyzed quickly, but also multi-method, multi-parameter, multi-information can be undertaken quantitative analysis through considering geo-technical test and geophysical information. After this method has been successfully applied to Xixia earth-fill dam detection, it is indicated that modern geophysical methods is effective to detect the diseases and faults in dam quality and this method is worthy of popularizing and application in the future.

Abstract: Due to the limited capacity of cotton-processing factory, machine-collecting cannot make sure the process progressing in time and will cause a bad heat dissipation of cotton or a high temperature and humidity. A cotton temperature and humidity wireless monitor is designed to solve the problem. In our experiment, we find that the collecting holes of the collecting tube play the most important part in the data collection. Comparison is made about the performance between round holes and diamond holes using FLUENT, we get the result that the diamond holes have a better collecting effects and a higher collecting accuracy.

Abstract: This paper describes the design of an on-line monitoring system for grid-connected photovoltaic plants. The proposed system consists of a meteorological data collection system for measuring meteorological parameters (e.g. irradiance, ambient air temperature, etc.), a set of data collection boxes for measuring electrical parameters (e.g. DC and AC current, DC and AC voltage, DC and AC power, etc.) and a PC. The collected data have been transmitted to the PC by two methods, wired transmission and wireless transmission. The software of the on-line monitoring system based on LabVIEW (Laboratory Virtual Instrument Engineering Workbench) package is used to process, display and store the collected data in the PC disk. The on-line monitoring system was installed in a grid-connected photovoltaic plant for an on-site measurement in Qinghai province in China. The obtained results demonstrate that it has the ability for data collecting, processing and analyzing and it meets the measurement requirements of grid-connected PV plants

Abstract: Insulation measurement system performance influence of insulation material selection formula as well as the material production and quality. This paper introduces the insulation performance measuring system and control theory, and the ablation experiments of main technical parameters and data processing and insulation material performance evaluation standards: adiabatic index, the linear ablation rate, mass loss rate calculation and evaluation.

Abstract: This paper researched on four different types cars, analyzing interior noise at the same speed under different points, the same point different speeds and the same car different speed different points, it is concluded that family car interior noise distribution law; Through analysis noise spectrum curve which can get the main frequency band, that may provide theoretical basis for automotive noise reduction. In addition, this paper gets that medium low-frequency noise(0-2Brk) are the biggest to composition car’s characteristics loudness from research on characteristic loudness curve, and with speed continuously improve characteristic loudness growth is very significant.