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This paper, using the finite element software ABAQUS, establishes the model of laser shock peening (LSP) of TC4 titanium alloy, and analyzes the influence of different parameters on the residual stress of TC4 titanium alloy and plastic deformation. The results show that LSP can make the surface of TC4 titanium alloy have large compressive stress and plastic deformation, hardness and prolong the fatigue life of materials. Laser energy and the impact frequency are the main factor of surface residual stress effects. The multi-point LSP can perform processing enhanced in surface area, and form residual compressive stress on the surface of the material and in a certain depth.

Micro cutting is a promising manufacturing method to obtain good surface integrity. Surface roughness shows size effect when the uncut chip thickness is smaller than the cutting edge radius. A special micro slot on the flank face of cutting tools was manufactured with discharge. Two groups of micro orthogonal cutting were conducted. The surface roughness of machined surface was measured and compared to each other. The results show that surface roughness decreases first and then increases with the ratio of uncut chip thickness to cutting edge radius. The surface machined with micro slot is better than that of without micro slot due to the micro slot restrain the back side flow of work piece based on the finite element model.

This paper takes the seismic performance of the existing building evaluation in Wuhan, analysis of the existing building on the seismic performance, and extract a certain characteristic parameters for quick retrieval and identification, proposed the idea of the of earthquake damage prediction database, build and improve the based information of the construction earthquake damage prediction, establish a fast city buildings earthquake damage prediction system.

Micro cutting is a promising way for manufacturing micro parts, especially micro three dimension parts. Micro hardness is an important character to evaluate surface integrity of machined surface. Micro cutting is different from macro cutting due to size effect of specific cutting energy because of the influence of the ratio of uncut chip thickness to cutting edge radius. A group of micro cutting experiments were conducted to investigate the cutting parameters on the micro hardness of machined surface. The micro hardness of machines surface decreases with the ratio of uncut chip thickness to cutting edge radius first, and then increase when the uncut chip thickness is smaller than the cutting edge radius. The micro hardness shows size effect due to the machined surface compressed twice with the round cutting edge. The micro hardness decreases with the distance increasing far away from the machined surface.

This paper proposes an optimization algorithm which combines climb algorithm and ant algorithm and use it to solve optimization problems of fusion rules in distributed detection systems .Firstly, algorithm takes Bayes risk as the cost function, uses Climb-ant algorithm to optimize the sensors' decision threshold and Bayes criteria to solve the fusion rules of fusion center. Ultimately, we get the system's optimal (or suboptimal) fusion rules and realize the optimization of fusion rules in distributed detection system. Theoretical analysis and experimental results show that the new method has higher accuracy and efficiency of the solution than the traditional MAP (maximum a posteriori), SA-MAP, GA-MAP, and Coordinate Rotation Method.

Using five-axis equipment for NC machining of free-form surface is an effective way to improve machining quality and machining efficiency, the surface shape and the five coordinate of the complexity of the machine tool movement led to its tool path planning technology is difficult. The paper aimed at the five coordinate NC machining of free-form surface and puts forward a five-axis NC machining method based on triangular facet model. The research based on triangular facet model, using constant scallop height method to calculate the step distance and improve the cutting efficiency to a great extent. In the process, tool path is generated, combining with the method of configuration space interference free.

This paper uses modern spectrum setimation to process stepped-frequency signals which have extracted to obtain high resolution range profile. This paper use FPE criteria and AIC criteria to estimate the order of AR model, and linear prediction is used to test the performance of AR model. Compared with conventional IFFT processing, the results of spectrum estimation is satisfactory, and the exact location of high resolution range profile is determined.

Transcutaneous energy transmission (TET) systems are designed to deliver power from an in vitro primary power source to in vivo implantable secondary over relatively large air gaps via magnetic coupling. This paper proposes an optimization method with given output power to meet different practical application. The transmission efficiency is the objective function; primary and secondary coils are design variables; constraints are based on bifurcation phenomenon and components peak over-voltage and peak withstand current. We have used MATLAB/ SIMULINK to verify the analytical results.

The structural diaphragm effects have been investigated in the past decades with major attention on the properties of diaphragm panels. The research observations made by the oversea researchers cannot be directly utilized to the design construction of Chinese light gauge steel structures due to the different configuration of profiled steel sheets, fasteners, and purlins in China. In this regard, the shearing strength and stiffness of diaphragm steel sheets are investigated in this study through numerical study. The profiled steel sheet and fastener are simulated by the ortho-anisotropic flat plate and three one dimensional nonlinear spring, respectively. The analytical models are developed for examining the shearing strength and stiffness induced by diaphragm effects of a cladding system. The made observations indicate that the diaphragm effects of the steel sheet on the structure are obvious.

The 3D visualization technology is a kind of means and methods to achieve the human-computer interaction. Instead of the discrete objects in container terminal yard, the cargo in bulk terminal yard is always being a form with particle. This paper gives a method which integrates modeling manually and real-time reconstruction automatically to achieve 3D visualization of bulk terminal yard. Since to meet the requirement of real-time rendering and also decision data computing fast, this paper designs the data structure to describe the digital stockpile formed with a hierarchy relationship between surfaces, sections and space points, and also considers the closest distance as the main condition for searching and updating an old section, to visualize the working process in bucket terminal yard.

3D visualization simulation is the important research method of port logistic production system, whereas the lack of uniform standard and interface of 3D simulation model, it is very difficult to share the simulation model resource, and which caused modeling repeatedly and developing efficiency lowly. Container terminal 3D simulation model repository should be considered as the key factor of solving the problems of developing low-efficiency and model no reuse of logistic system. This paper classified the model resources required by container terminal 3D simulation, explained the functions of container terminal 3D simulation model repository, and gave its framework. Finally, we discussed the key techniques to implement the container terminal 3D simulation model repository.

With the further research of large container terminal machine going, promoting single equipment’s efficiency cannot greatly enhance the whole logistics service level of container terminal, thus considering the cooperation of each machine of container terminal from the macro view has become more and more important. The cooperative virtual environment uses distributed virtual reality technology as to build a platform that sharing status data and meeting human-computer interaction. Through analyzing the container’s operating process and combing the typical characteristics of handling machine, this paper proposed a new novel method for container terminal machine cooperation and mutual interaction of each cooperative unit in the virtual environment, so it can present the imbalanced state of production system in the operation process directly and help to make fast decisions.

The aim of the current study is to figure out the relationship between the oxidative damage in cardiovascular system and lead exposure. Oxidative damage was investigated in the heart and aorta of rats exposed to lead acetate for 6 weeks. Male wistar rats were randomly divided into three groups: low-dose (10 mg/kg), high-dose (40 mg/kg) lead acetate and control groups. The rats in low-, or high-dose groups were received 10 mg/kg and 40 mg/kg lead acetate by garages, and the rats in control group were administrated same amount distilled water only. We compared the three groups in terms of the level of T-SOD, NOS, and MDA in serum and heart, aorta and histological examination. We found the activity of T-SOD, NOS in rats treated with low and high doses of lead acetate were significantly lower than in the control group. The content of MDA in the low and high doses of lead acetate groups was significantly higher than in the control group. In addition, the microscopic morphology of heart and aorta in the low- and high-dose groups showed differences from the control. Oxidative damage may be involved in the process of heart and aorta dysfunction induced by lead exposure.

Incremental point clouds registration is studied in this paper. A rapid method for point clouds registration based on reference points is proposed, which consists of the coarse registration and fine registration. Firstly, a set of reference points is applied as an assistant utility to measure the object. The transformation parameters are estimated by using the reference points only for coarse registration, and then dense point clouds data will be transformed to the same coordinate system. Secondly, taking the coarse registration results as the initial value, the improved Interactive Closest Point (ICP) algorithm is used in fine registration the original corresponding points are established rapidly by using the k-d tree searching algorithm. Finally, Preview Model Parameters Evaluation Random Sample Consensus (PERANSAC) algorithm is utilized to remove outliers. The experimental result shows that this method in finding original corresponding points can greatly improve the computation efficiency and also improve the registration accuracy.