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When the wharf structure is completed, the temperature is different with the one at the usage period. The temperature difference will lead to the temperature strain, and create the lateral deformation and internal forces of the piles. Based on the assumption of the free temperature difference of beam-slab-system, the spatial simplified calculation model of the foundation pile and the stiff platform about the temperature stress in all-vertical-piled wharf is first proposed, the related calculation method is also given. The numerical example shows that the accuracy of this simplified method could meet the demand of preliminary design. In order to reduce the pile-top internal forces, the foundation piles should be arranged symmetrically. The pile-top internal forces are in direct proportion to the forth power of the pile diameter, with the increase of the pile diameter in all-vertical-piled wharf, the analysis of the temperature stress must be taken seriously.

All the drive motor of AGV are DC servo motor in the domestic stage , but it has some shortcomings such as more power consumption ,noise, magnet coils easy to burn, life is short and so on in the actual production. Through two series of comparative tests on the DC motor and AC motor driven AGV get two drive mode start time, start acceleration, top speed and other values.Through numerical processing and analysis know that AC motor as a AGV drive motor is better than Dc servo motor..

Low carbon Tourism Education" refers to the tourists and tourism practitioners, low carbon Tourism Education and guidance activities. The development of low carbon tourism education is an important content of the construction of low carbon economy, the promotion of tourists and tourism practitioners of low carbon idea and behavior, has the vital significance to promote tourism enterprises in low carbon operation management and low carbon Tourism Scenic Area Construction etc. This paper focuses on the development of low carbon Tourism vigorously industry requirements, taking Huzhou Anji Daxi village as an example, through field research, on the existence of low carbon Tourism Education in the village of "Happy Farmhouse" problems are analyzed, and put forward the corresponding countermeasures, with a view to the education level for the construction of low carbon tourism economy to find a it is feasible and has the model significance of the road, and other areas to develop low carbon Tourism " Happy Farmhouse" experience.

by using optical microscope and scanning electron microscope (sem), for minitype automobile driving axle half shaft fracture piece of organization and the fracture characteristic is analyzed and the results show that the axle shaft of conditioning treatment in the quenching temperature high enough, make its surface and center organization exists in the group more ferrite, caused the artifacts of the final hardness and fatigue strength is insufficient, led to the use of half shaft torsional fatigue fracture.

Nano-SiC/MC nylon6 (MCPA6) composites were prepared by in situ anionic polymerization，followed by properties’ characterization of composites and morphology. FTIR shows that there is no change in the functional groups of MCPA6 by adding nano- SiC and only physical interaction happening in the composites. SEM reveales that bonding state of the two-phase interface of the composites has been affected by the ratio of nano-SiC. Nano-SiC (2.5 wt-%) is fine dispersed in MCPA6 matrix, which enhances interface compatibility and bind strength between nano-SiC and MCPA6, the best comprehensive properties of the composite are obtained. Comparing with untreated MCPA6, the notched Izod impact strength, tensile strength and flexural strength are respectively increased by 208.8%, 81.1% and 27.9%, while the Vicat softening temperature is increased by 20.2%.

Rotational axes augmented to general Wire Electrical Discharge Grinding (WEDG) and to the cylindrical wire EDM processes (CWEDM) are reported in this study. On their removal mechanism, a quantitative analysis based upon wire EDM discharge-angle is proposed to clarify comprehensive understanding of the novel mechanisms. The proposed quantitative analysis provided a better understanding for multi-axial WEDG and WEDM processes. Besides, an ultrasonic assisted UA-WEDG system associated with a conic oil cup was then developed in this study to improve the machining efficiency and the surface integrity by improving debris processes. Its significant effects on dressing processes of micro tools were verified experimentally and some removal saturation for both configurations were discussed. Dressing effects meso-scaled rod and screw by both CWEDM and WEDG mechanism were also compared and discussed.

Wireless Sensor Network (WSN) is used for such tasks as surveillance, widespread environmental sampling, security, and health monitoring widely. In this paper, a WSNs topology is proposed for lightning monitoring of distribution lines, which decides the number of nodes, routing protocol and power efficiency. The WSNs is deployed along the distribution line with nodes mounted on tall towers, which is used to monitor the lightning activities and accomplish fault diagnosis. At last, a monitoring system based on WSN is fabricated.

The paper presents the making of driver-motor-reducer and turntable system, and builds a mathematical model of this system. The design of a self-tuning PID controller and the simulation of the whole system are realized by using the MATLAB fuzzy logic tool. The simulation results show that the turntable servo system with the fuzzy self-tuning PID controller has a slight overshoot, fast response, good accuracy and robustness etc.

This study focuses on the method to determine the slip surface in waterfront soil slope analysis under static and seismic conditions. Based on the limiting equilibrium theory and the stress analyzing method, a new method to determine the slip surface is suggested. In the method, the two basic assumptions are considered in order to solve the problem. One is that the slip surface comprises a series of straight lines, and the other is that the interslice boundary is an inclined plane. Three balance equations for any slice are proposed. The iterative method to solve the balance equations is also suggested. In the new method, the slip surface is obtained slice by slice going from downhill to uphill in terms of the balance equations of the slice, not predefined.

In this paper, some deep cryogenic treatment experiments are first applied to 5A06 aluminum alloy welded joint at liquid nitrogen temperature （-155°C ）for 4h, 8h, 10h respectively. 5A06 alloy welded joints before and after deep cryogenic treatment are observed by X-ray diffraction and scanning electrical microscopy. The experimental results have shown that the deep cryogenic treatment causesβphase of alloy to disperse and makes the grain smaller than that of joint before deep cryogenic treatment. Therefore, the mechanical properties of 5A06 alloy welded joints after deep cryogenic treatment are greatly improved.

An image watermarking algorithm using Least Significant Bit is presented. Firstly, Logistic chaotic map is utilized to generate embedding bits for the watermark. Then, the discrete cosine transform is performed on the host image, and the hiding bit is embedded in the coefficient of discrete cosine transform by replacing Least Significant Bit, which causes minimal distortion of the host image.The original host image is not required when extracting the watermark . Experimental results show that the watermarked image almost has no difference from the original host image, and the quality of the extracted image is satisfying, the capacity of this algorithm is high. This algorithm is robust to many attacks, such as noise attack, JPEG Compression attack. Introduction

During May 12th 2008 Wenchuan earthquake with the magnitude of 8.0, a 4-span rigid frame arch bridge named as Xiaoyudong Bridge which situated close to the epicenter was hit by strong ground motion and was severely damaged. The earthquake response analysis of the bridge was made using FE software MIDAS based on recorded ground motion during the Wenchuan earthquake in this paper. The study showed that the main and minor arch legs on the both ends piers were weak links which may be damaged firstly under strong ground motion. The next damage at the pier with weakest horizontal stiffness is one of the important reasons causing the bridge collapsed. This paper will introduce our work on those respects and some drawn conclusions.

Firstly several seismic simplified methods commonly used for deep circular tunnel are evaluated and the difficulties in response displacement method are pointed out. Then the analytical solution of soil spring coefficient and soil response of deep circular tunnel is derived from using complex variable theory of planar elastic theory based on pseudo-static hypothesis. The analytical solution has been verified by comparing its predictions with results from an analysis in finite element method. It is concluded that the analytical solution can be regarded as one feasible reference for the simplification of response displacement method.

The damage of bearing will change the boundary condition for whole bridge, if we do not take account of bearing failure, the error of structural analysis and the unreasonable in design will be made. In this paper, the effect of possible bearing damage to whole bridge during strong ground motion is studied through examining the seismic performance of a multi-span continuous girder bridge which is a real damaged bridge during the Wenchuan earthquake in 2008. Proper analytical restoring force models of bearings are proposed, which can simulate the seismic performance of the bridge before and after the bearing damage suitably.

The use of P92 is becoming more and more widespread in high temperature steam pipe of super-ultracritical power station boilers, it’s key material for the manufacture of boiler’s four main pipes. The properties of P92 are closely related with its microstructure, and the microstructure of P92 has strong relationship with its’ composition and hot processing technology. Three types of P92 with different composition have been prepared. The relationship of delta ferrite between composition, smelting and heat forging process has been investigated for these three samples. The results show that the delta ferrite can be avoided by the adjustment of composition and making process, the delta ferrite will occurred in the matrix of P92 which without delta ferrite before heat treatment if the heat temperature exceed 1200°C , the delta ferrite existed in P92 ingot matrix resulted from the composition cannot be eliminated by hot working and heat treatment.