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With the rapid development of world economy, the energy crisis has become one of the urgent problems to be solved. Photovoltaic technology is a green new energy industry, no pollution is widely used all over the world. Typically, for photovoltaic component installation, only considering the utilization of components support cost and area, and the arrangement of components have not given enough attention. Photovoltaic module in use process will inevitably encounter the shadow, the shadow changes to make appropriate adjustments to the PV module arrangement can enhance the power generation capacity. Effect of the shadow on the photovoltaic system performance can be effectively used for photovoltaic component to bring help, is of positive significance. This study analyzed the villa model typical, and the rectangular shadow is modeling, in order to analyze the influence on the photovoltaic component. Through the conclusion of this study can determine the horizontal and vertical components of photovoltaic components which caused little damage, and provide a reference for future research of shadow and photovoltaic system performance.

By taking a simple supported concrete-filled steel truss bridge as the research object in Guangzhou, some jobs have been done such as the simulating calculation and the real-time monitoring of side span steel girder during the jacking construction procedure, and contrast analysis was conducted between the calculating stress value and the measured stress value, which may draw a conclusion that the safety could be satisfied during the jacking construction procedure

Al-(4-5)%Cu alloy was served as experiment material，the effect of pulsed currents on the solidification structure was investigated. During the solidification process of Al-Cu alloys, pulsed currents was added into the melted alloy in the crucible .The change of temperature curve and microstructure about the alloy was investigated in such conditions by temperature-recording instrument and optical microscope.The results showed that pulsed currents can shorten the temperature region of crystallization and refine the grains of the alloy,which crush the dendrite and make the solidification structure non-dendrite, presenting columnar and equiaxed grains which are distributed evenly and whose space between crystals are reduced. This investigation firstly started to study the relations between the temperature region of crystallization and organization structure of solidification. Finally, the mechanism of metal solidification affected by square wave pulsed currents was discussed.

The uneven illumination distribution would affect the accuracy and stability of an optical multi-touch system. In this paper, different self-adaptive methods based on the type of interference source are integrated. When the ambient lighting changes, the luminance of the captured image will changes accordingly. This method tests the type of interference source by the speed and the region of ambient lighting change, and uses different function to update the background image rapidly. Experimental results show that with the help of the presented solutions, the ghost points are efficiently reduced and the system can adapt to the changes of ambient lighting in only 1 second.

A slope SOI-LDMOS power device is proposed for high-voltage. When a positive bais is applied to the drain electrode, holes are induced and astricted by the slope buried oxide layer. So a high density positive charge layer is formed on the buried oxide layer. The electrical field in the buried oxide is improved as well as vertical breakdown voltage by the layer. Because the thickness of the drift region linearly increases from the source to the drain, the surface electric field is optimized, resulting in increase of lateral breakdown voltage. In this paper, the electric characteristics of the new device are simulated by Medici softerware. The result is shown that above 600 V breakdown voltage is obtained at 1μm thick buried oxide layer. The breakdown voltage is higher by three times than that of conventional SOI LDMOS.

The concrete decks in wide box composite girder bridge carrying vehicle load directly are easy to failure. So the decks in approach bridge of Jiubao Bridge are designed to renewable component. Several deck removal plans were put forward based on the structure characteristics of the Jiubao bridge. Spatial finite element model of the bridge was set up and the responses of approach bridge under different removal plan were analyzed. The analysis results show that methods proposed in this paper about deck removal in local position or in whole span are feasible; however different whole span removal method affect the mechanical behavior of the approach bridge heavily.

In order to explore the feasibility of a class of eutectic ionic liquids in soil heavy metal repair problems. The acetamide-alanine eutectic ionic liquid was prepared and its properties of density, viscosity, surface tension and electrical conductivity were measured, and it’s application effect of Cd²⁺ extraction in soil was studied. The results showed that the extraction amount of Cd²⁺ in soil by the acetamide-alanine eutectic ionic liquid with a concentration of 0.6 mol/L reached the maximum of 99.67%. The physical properties of a melamine-alanine eutectic ionic liquid having a concentration of 0.6 mol/L at a temperature range of 303.15 K-343.15 K were determined. The 0.6 mol/L acetamide-alanine eutectic ionic liquid was compared with the ionic liquid and the related organic acid aqueous solution prepared under the same conditions, and the acetamide-alanine eutectic prepared by the experiment was found to be eutectic. The ionic liquid has better extraction efficiency for heavy metal Cd²⁺ under the same conditions, and is a good soil heavy metal extractant.

It has been proved by the seismologic observation of 5.12 Wenchuan Earthquake that a large number of shallow-buried depth mountain tunnels at the portal are underwent severe damage. Earthquake waves, especially Rayleigh waves may be a major factor causing the damage. The numerical model of the shallow-buried depth mountain tunnels by FLAC3D is establishes in this paper, and the dynamic responses of the shallow-buried depth mountain tunnels under the action of Rayleigh waves are simulated by loading on normal Rayleigh waves. The effect of different strength of surface waves is simulated by the in-site blasting tests. The dynamic responses of the tunnel lining under the action of Rayleigh waves are obtained by filtering and composition separation in order to discuss the incidence and mechanism of action. The results show that the dynamic responses of tunnel lining under the action of Rayleigh waves mainly focuses on the portal of tunnel, namely the buried depth and lengthways depth of the tunnel are 0~16m and 0~20m, the tunnel lining is damaged easily in the incidence, and the multiplicative effect of Rayleigh waves often occurs at the portal; beyond the incidence, Rayleigh waves attenuate rapidly and the dynamic responses of the tunnel lining decreases gradually, which has little effects on the safety of tunnel structures.

A novel image segmentation algorithm based on fuzzy C-means (FCM) clustering and improved particle swarm optimization (PSO) is proposed. The algorithm takes global search results of improved PSO as the initialized values of the FCM, effectively avoiding easily trapping into local optimum of the traditional FCM and the premature convergence of PSO. Meanwhile, the algorithm takes the clustering centers as the reference to search scope of improved PSO algorithm for global searching that are obtained through hard C-means (HCM) algorithm for improving the velocity of the algorithm. The experimental results show the proposed algorithm can converge more quickly and segment the image more effectively than the traditional FCM algorithm.

We introduce the differential evolution (DE) algorithm in the geophysical nonlinear inversion field. We set up a nonlinear inversion model of DC electrical sounding data using the DE algorithm. A comparison between the model and actual data suggests that the DE algorithm is more accurate and faster than existing algorithms. The study results presumably open new vistas in geophysical nonlinear inversion, and the DE algorithm may find application in two-dimensional or three-dimensional electrical sounding inversion. In the end, we applied the DE algorithm to the polymetallic ore exploration successfully in Inner Mongolia.