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This paper designs an image encryption algorithm with a dynamical feedback operation based on sensitive chaotic system. In the proposed algorithm, the piece wise linear chaotic map is selected to construct pseudo-random keystream sequences. The pseudorandom keystream sequences are used to permute and substitute the plain image data. To enhance the complexity and security of the algorithm, each pixel is dynamically confused by its two previous adjacent encrypted pixels which are specified by a quantized binary tuple derived from a chaotic element. Both theoretical analysis and experimental tests show that the proposed algorithm is secure and efficient.

This paper investigated the influence of the inoculation volume of dewatering sludge on thermophilic anaerobic digestion in residue of fermentative hydrogen production using combined sludge and food waste in batch experimental systems. The inoculum to residue ratios were 10%, 30%, 50%, 70%, 90%, respectively. The results showed that the biogas production increased with the inoculation volume except for 90%,and the optimum inoculation volume was 70%.

The flux growrh method is employed to grow the Yb:LuPO4 crystal using lead pyrophosphate Pb2P2O7 as the high-timperature solvent. The infrared spectroscopy(IR) was tested to determine the purity of the obtained crystal. The absorption spectra of the 5% Yb-doped Yb:LuPO4 crystal was measured at room temperature. Three absorption peaks that located on 985nm, 976nm and 953nm were found, and the absorption cross sections on the absorption peaks were calculated respectively. The results shows that Yb:LuPO4 crystal has potential to be applied as laser material.

Making sure the safety of wind turbine tower structure in service is particularly important with the development of offshore wind turbine facility. In order to make mechanical characteristics of structure explicit, dynamic responses of structure under three different types of seismic waves were analyzed by m method and considering monopile-soil-structure interaction, then comparison with the situation when structure was consolidated in the bottom was made. The result shows, dynamic response was most obvious under the action of far-field seismic wave in such high-rise structure as wind turbine tower. When the acceleration peak of far-field seismic wave was in the level of 8-degree rare earthquake, structure would be unsafe with an oversize displacement at the top of tower. Compared with structure consolidated in the bottom, dynamic response of structure was effected by the intensity and stiffness of soil around the pile. The interaction of soil and foundation was needed to be considered in the analysis of dynamic response.

The main purpose of the paper is using multi-functional sensors to detect the vehicle attitude (the tilt angle of vehicle), and many other vehicle information. Combining all the information, the adaptive front-lighting system can achieve the real-time control of the pitman arm and yaw angle for automobile headlight system. The feasible control methodology could highly enhance the safety of driving and electronic additional value in automobile industry. In the paper, various conditions of HID (High Intensive Discharge) headlight system could be controlled, such as the control of pitman arm and yaw angle, are widely discussed. In the pitman arm angle control, we use G-sensor to detect the unbalanced vehicle caused by load, rugged road, uphill and downhill. Finally, combining the velocity obtained from the ECM (Engine Control Module), the leveling motor control for headlight pitman arm angle real time and adjust will be realized. On the other hand, we use the potentiometer and micro switch to sense the direction and quantity of steering wheel angle, the swivel motor control for headlight yaw angle real-time adjustment is completed.

According to the characteristics of the elevator fault vibration signals, proposing a Based on analysis of time series AR bi-spectrum elevator fault diagnosis. When the zero-mean, non-Gaussian white noise elevator device, the vibration signal using sampling to establish time series autoregressive model (AR model), resulting in AR bi-spectrum. Bi-spectrum signal processing is a new, powerful signal processing technology, which can be described the nonlinear coupling, suppression Gaussian noise and retention of phase information, you can get the elevator working status of the different dynamic characteristics. The results show that bi-spectral analysis with AR elevator failure is feasible and effective.

In this paper, the speed control system controlled by motor speed was designed to control forward speed of underwater robot precisely. Based on the theory of double closed-loop speed control, motor control system was modeled firstly, and then regulator parameters were designed based on the engineering approaches. According to the characteristics of forward movement, the mechanical construction of sub-mini underwater robots and the comparison of various system designs, the double closed-loop regulator parameters of sub-mini underwater robots were obtained. And the propulsion system of sub-mini underwater robots was equipped with speed and current double closed-loop control. All the experimental results showed that within a certain range of motor speed, no static error could be guaranteed and the variable speed of underwater vehicle could be achieved.

This research to carry on the 3D model of electro-magnetic-mechanical forming analysis, its goal is lies in discusses the magnetic force which electric current produces the influence which creates to the plate, like distortion, stress and so on aspects. But before the analysis, establishes the 3D model first, in converges in ANSYS, gives the material parameter, the boundary condition and so on, then carries on the solution, subsequently obtains the analysis result. Knew by the analysis result, in approaches corner on the U shape coil dull position, its amount of deformation is the maximum value, and stress maximum value also in corner.

The effect of microstructure on transport properties of nano-polycrystalline La0.7Sr0.3MnO3-δ films, which were prepared by DC magnetron sputtering at various working pressures and followed by air annealing at 973K for 1h, has been investigated. The result indicates that the change of working pressure can change the microstructure, metal-insulator transition temperature (TIM) and peak resistance but does not change the transport mechanism for the films. The vacancy defects have an important effect on the transport properties of the films. Higher working pressure tends to decrease the density of vacancy defects. Low vacancy defects account for the high TIM and low resistance of the films. In the region of T > TIM, the charge carriers are moving in variable range hopping mode. The behavior of resistance decreasing with the increasing of temperature at low temperature (T

The building of the formerly Yihe Spinner Factory in Shanghai is a protected. To ensure its serviceability, appropriate retrofitting is necessary. Structural analysis based on the inspection result was performed. It is shown that the bearing capacity or the ductility of some members in the original structure as well as the retrofit proposal are inadequate. Strengthening design was then performed. The effect of the subsequent retrofitting process on the strengthened structure was analyzed. The historical building is then properly protected and the new manufacturing requirements are meet through the retrofitting and strengthening design. The proposed methods can serve as references for relative research or engineering practices.