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This paper analyzes themechanical manufacturing safety management status, looking for the causes ofthe safe hidden trouble from the aspects of temporaryelectricity application, manufacturing material and schedule control onsite and presenting security correction measures.

A simulation model about photovoltaic array which can track the maximum power point with the function of changing the it's resistances' structure is developed based on PSCAD. By the simulation of connecting the model with a associated electro circuit, we can draw the conclusion that the model can almost review the character of the actual device. Key worlds: photovoltaic array; MPPT; PSCAD; simulation

In order to digitize the signal of high frequency or ultra-high frequency, clock distribution technology with the same frequency but different phase is utilized as a solution to this difficulty. The principles of high-speed analog-to-digit converter (ADC) by the lower rate ADC module, key technology and key module of the data acquisition systems are studied. From the aspects of system architecture, clock distribution module based on the AD9520, ADC module based on the AD9480 and data processing, the design method of ultra-high-speed ADC by clock distribution mode are explored. The results show that: driving many ADC modules with serial clocks of the same frequency but different phase in parallel to sample the same signal, the sampling frequency of the ADC system is the sum of each ADC sampling frequency. Four AD9480 modules are driven by four-way 250MHz clocks with phase fault 90°, respectively. And 1GHz samples per second can be attained, which is four times of the sampling frequency by monolithic AD9480.

For the echo of the laser signal was relatively weak and accompanied by a lot of noise in a foggy condition, a multi-pulse cumulative method for enhancing weak laser signal was proposed. The enhancement principle and method of multi-pulse signal accumulation was studied, and with it the weak signal was processed. The matched filter algorithm was used to extract the characteristics of laser echo signal, the original signal and the accumulated signal was processed by the matched filter, respectively, which greatly improves the signal to noise ratio (SNR). The experimental results show that: four separate laser signals accumulated together enhance SNR by twice; the accumulation of multi-pulse laser signal can effectively improve SNR, and the matched filter can strengthen the signal while suppressing noise.

with the difficulties of extracting the feature of faint laser signal reflecting from non-cooperative target in foggy conditions, the spatial correlation threshold filtering approach was proposed based on spatial correlation filtering. The thought, theory and implementation methods of the spatial correlation threshold filtering was elaborately studied, especially, the selection of the threshold for the filter was analyzed. A comparative study of threshold filtering, spatial correlation filtering and spatial correlation threshold filtering was carried out to verify the filtering effect for the laser signal reflecting in the foggy environment, the experiment results shows that: spatial correlation threshold filtering method has the most effective filtering. The processing results show that the new method can effectively eliminate noise and keep weak laser signal characteristics, which lays solid foundation for identification of target nature.

This paper introduces modeling method for calculating nodes responses of transmission-line network directly in the time domain. Arising from classical telegrapher equations, the time-domain model of transmission line is gained. The transmission-line model, together with transmission-line nodes model, form the network model. Using the time-domain modeling method, transient responses for two given networks are gained. The injection experiments to cable networks are done to validate the calculating results. The consistency of calculating results with measure results indicates the model is feasible.

This document reflects the warranty management situation of Chinese manufacturing enterprise by investigating 93 manufacturers including automobile, electronics and machinery equipment. By the investigated data of warranty cost ratio of revenue, we can find the gap between Chinese manufacturers and abroad. The next, through the statistics analysis of factors influencing the warranty cost, we find that the management of suppliers and outsourcers, cost control strickly and the cost accounting system are helpful to decrease the warranty cost. According to the analysis, the paper make suggestions in warranty cost management to Chinese manufacturers

A new technology of initiative protection for lightning stroke based on electric field cancellation theory is presented in this paper. The real time lightning detection system and the active protection equipment are adopted. By using this new method, the protection technology of direct lightning stroke can be changed from little current triggering to weakening the electric field near the weapon system, and the down leader of charged thundercloud can be repulsed by the artificial opposed field. So the lightning discharge condition in this protection region can be destructed, and the lightning hazard to the protected equipment is eliminated radically. It effectively reduces the electromagnetic radiation, ground potential reaction and step voltage caused by the high current along conducting wire in the conventional lightning rod protection technology.

A HEMP Simulator was constructed based on coaxial peaking technology. The experimental results show that: a HEMP field matching the MIL-STD-464A standard is generated under the bounded wave transmission line when the parameters are selected reasonably; the variation coefficient of output wave parameters such as peaking filed strength, rise time and half time show that the repeatability of the HEMP simulator are very good; there is linear relation between the peaking field strength and the charging voltage of the Marx generator.

Pure wood vinegar is widely used in industry, agriculture and other areas as regulators, but the wood vinegar which produced usually is filled with oil on the surface .The paper mainly study on removing the floating oil on the surface of wood vinegar,choosing the best surfactant called Tween 80 to removing the floating oil and making wood vinegar in a steady system. By this way, it will not appear oil on the surface of wood vinegar for more than half an year, which will broaden the commercial application of wood vinegar

Catalytic combustion of toluene on Cu-Mn complex oxides was investigated. The catalysts were prepared by urea-based hydrothermal method and characterized by XRD and SEM. It was found that both the decrease of the Cu/Mn molar ratio and the increase of reaction time contributed to improving catalytic activity for toluene combustion. The temperature for 99% conversion of toluene (T99) was lowered to 210°C. The main crystalline phases of Cu-Mn complex oxides were CuO and Cu0.45Mn0.55O2. It was showed that the existence and high dispersion of Cu-Mn complex oxides were related to the catalytic combustion activity.

The solidification behaviors of titania(TiO2)-water nanofluid and deionized water (DI water) were investigated using differential scanning calorimetry (DSC) at cooling rates of 1.5—9.0 °C/min. The nanofluid with 0.3 wt% TiO2nanoparticles was prepared by dispersing the nanoparticles into DI water. The dispersion and stability was confirmed by a particle size and zeta potential analyzer. Experimental results show that the solidification temperature of the TiO2-water nanofluid was higher than that of DI water at the same cooling rate. The contact angles of TiO2 and the interior surface of the sample holder were measured, and the free energy barriers (FEB) of nucleation of the TiO2-water nanofluid and DI water were calculated. It was found that the FEB of nucleation induced by the TiO2 nanoparticles was lower than that by the flat surface, resulting in lower supercooling degree.