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In this paper, the GC cup truing technology on resin bond diamond grinding wheel is studied, and the parameters of truing the diamond grinding wheel process are optimized. Also the contour accuracy and microscopic topography of the diamond grinding wheel are analyzed quantitatively. Besides, the method of evaluating the dressing effect of diamond grinding with the roughness of grinding wheel is proposed.

By using printability tester for printing on ordinary white cardboard and light beam hologram paper, measuring spectral information and chrominance information of the two samples, and then perform spectral fitting by analyses their color characteristics, The aim of this research was to propose one method for color calculation of printing on light beam hologram papers, according to the color information of ordinary white cardboard.

In order to study the LED light source illumination and the correlated color temperature effect on the human eye visual performance and physiological changes, through the comparative experiments of visual task performances under the different color temperature (3000K low color temperature, 4000K intermediate color temperature) and the different illumination (1145lux high intensity, 500lux middle intensity, 288lux low illumination), study the relationship between the biological effect and visual performance from two aspects of the visual perception performance and the physical efficiency such as blood pressure and pulse. Research indicates that color temperature 3000K or 4000K, intensity of illumination in about 500lux LED light source is suitable to visual task.

This paper first introduces the types and characteristics of HWSN, expounds its typical architecture, through comparing with homogeneous wireless sensor network, the performance of HWSN is quantitative calculated, analysis results show that HWSN can improve the reliability of data transmission, reduce the energy consumption of data transmission, reduce the delay of data transmission, and with the increase of network scale, highlight the advantages of heterogeneous networks. HWSN covering algorithm performance evaluation indexes are given finally.

According to the characteristics of the dynamic force of jet elements, a kind of simple pendulum test system was presented. The dynamic jet force value was obtained indirectly by the acceleration value of the jet element under its force. The mathematic model of the test system was established and the test errors of the amplitude and delay time were analyzed. A processing method of dynamic force test data was presented based on the test curve and the parameters of amplitude and delay time were obtained. The result indicates that the test method can satisfy the testing requirements of dynamic force and it has advantages of simple structure, low demands of testing condition and simple method of data processing.

Use gas-driven light gas gun is one of the techniques extensively used to achieve hypervelocity projectiles. The device was made up of a compressed gas gun as the first-stage drive. A new type high pressure pneumatic injecting system of gas-driven light gas gun for hypervelocity launching is introduced. As a critical component of the injecting system, the high pressure pneumatic valve was designed. Functions of the pneumatic valve were preserved and relevant techniques were discussed. Besides, a high pressure pneumatic mass flow control test-bed using inert medium was built in order to study the dynamic response characteristic of high pressure pneumatic valve in gas-driven light gas gun. To ascertain the response delay time of the valve, several turn-on and turn-off experimental tests of the valve were initiated. The results suggest that: the pressure of pneumatic electromagnetic valve gas supply circuit seriously influenced the properties of high pressure pneumatic valve; the mean delay time of the high pressure pneumatic valve was 190ms approximately at 6.5MPa gas pressure of the pneumatic electromagnetic valve gas supply circuit.

A control mathematical model in pitch and yaw direction is presented to apply on missiles controlled by double-channel with style canard. Based on the mathematical model, the influence of deflection angle measurement error and actuator performance on actuator control is analyzed. The results show that the measure error of lean angle and actuator delay will produce control coupling in pitch and yaw direction and that will reduce control efficiency.

Traditional discrete method, converting order continuous system to order difference equation, describes system using the information of sampling points. But the system response in the time of will not be sufficient to describe the system when sampling period is much larger than the bandwidth of the system. By analyzing differential discrete method, our design gives an improvement to take out of the influence of the system bandwidth. In this method, order continuous system is transformed into order difference equation and the information of sampling points can be used to describe the system. It is proved that modified difference transformation is better in interference rejection than traditional difference transformation by comparing the simulation between the two transformations. The hardware implementation using TI's TMS320F2808 shows that modified difference transformation has a deviation close to round-off error based on simulation with a linear increase of operating time.

A high-pressure-pneumatic mass flow control test-bed using inert medium was built in order to study the transient flow characteristic of high pressure gas feed system in ram accelerator. The structure of a new type measurement system of transient flow characteristic experiments applied to the test-bed was introduced as also. Measurement tests that high pressure gas-flow ejecting into a tank with exhaust-back-pressure through a high pressure fueling valve were conducted to ascertain the transient discharge coefficient. The results suggest that: The transient discharge coefficient increases with the inlet pressure difference of high pressure fueling valve according to polynomial law. Correlations between inlet pressure difference and transient discharge coefficient was obtained based on the experimental data. The correlation coefficient between the least square fitting curve of the correlations and experimental results reaches 0.994.The system could be used to study the change regularity of pressure and time in the fueling process of high pressure gas.

The traditional valve control hydraulic systems have serious challenges in the harsh environment underground. The mathematical model of this new form of "motor - quantitative pump" controll system was established and simulated by using AMESIM software in this paper. According to the results of comparative analysis of the orifice parameters and the way to input signal, related parameters was determined, which can meet the characteristics of the system.

The integrated optimization of structure and control systems is investigated for 2-D single structure using a typical planar frame taken from a building. The vibration control model is established for the plane frame, and the LQR algorithm is used to obtain equivalent stiffness and damping parameters of assigned passive controllers. The integrated optimization model, including design variables, the objective function and constraint function, is built. The design variables are the size parameters of structural elements, the parameters of the weighted matrix, the number and locations of the controllers. The maximal displacement of the controlled system in time domain is introduced as the objective function. Genetic algorithm is adopted to solve such a kind of optimization problem with discrete and continuous design variables. The results of a numerical example show that the proposed method is reasonable and effective for the integrated design of control/structural systems subjected to seismic load.

In this paper, we introduce a novel technique for mining fuzzy association rules in quantitative databases. Unlike other data mining techniques who can only discover association rules in discrete values, the algorithm reveals the relationships among different quantitative values by traversing through the partition grids and produces the corresponding Fuzzy Association Rules. Fuzzy Association Rules employs linguistic terms to represent the revealed regularities and exceptions in quantitative databases. After the fuzzy rule base is built, we utilize the definition of Support Degree in data mining to reduce the rule number and save the useful rules. Throughout this paper, we will use a set of real data from a wine database to demonstrate the ideas and test the models.

Based on lots of gas emission from gob in mining faces, and the actual situation that gas accumulates in the top corner of the working face in Chang Ping coal mine, it is introduced in the paper that the successful experience about the technology of gas drainage to gob with long bore-holes along roof strike, the conclusion would be had obtained obvious security and economic benefits.