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By the method of EVA emulsion coating, cron stalk-magnesium oxychloride cement composites (C-MOC) was modified to study the effect of EVA emulsion content on C-MOC density, the coefficient of thermal conductivity, water resistance and mechanical properties. Furthermore microstructure of C-MOC was analyzed by SEM. The results show that: with the increase of EVA emulsion content, the coefficient of thermal conductivity and softening of C-MOC increase, but water absorption reduces. When the content is 80%, the flexural strength after 28 days could reach 3.65 MPa and the compressive strength is 4.69 MPa, reaching the maximum. At the same time, C-MOC density is 816 kg/m3 and thermal conductivity is 0.111 W/(m·k). Water absorption is 36% and softening coefficient was 0.47. It is believed that EVA emulsion could form a thin film on the outer surface of the corn stalk by microscopic analysis, increasing the roughness of the straw surface and reducing the gap between the stalk. Since the EVA emulsion has good compatibility with the magnesium oxychloride cement, they could constitute a whole jointly with glue liquid, crystal and fiber, playing the role of enhancing the surface. Therefore, water resistance, thermal conductivity and mechanical properties of C-MOC have been improved effectively.

Based on the Rayleigh-Sommerfeld diffraction integrals, the closed-form expression of nonparaxial cosine-squared Gaussian beams in free space is derived. The power in the bucket (PIB) of nonparaxial regime is introduced to characterize the beam quality of nonparaxial beams in the far field. It is found that the intensity and PIB of nonparaxial cosine-squared Gaussian beams depends onfparameter, decentered parameter, and the PIB is additionally depends on the bucket’s size taken. For a given bucket’s size, the smaller decentered parameter andfparameter result in the better power focusability in the far field and the better beam quality.

Based on the propagation law of partially coherent beams, the analytical expression of the beam width, waist positions and the far-field divergence angle of partially coherent sinh-Gaussian (ShG) beams through an astigmatic lens were derived. The effect of astigmatism and spatial coherence parameter on the beam parameters was mainly analyzed. It is found that the beam width depends on the astigmatic coefficient, spatial coherence parameter, decentered parameter, fresnel number and propagation distance in general. The astigmatism results in a difference between the beam widths, waist positions and far-field divergence angles in thexandydirections.

In this paper, an effective motion comparison method based on segmented multi-joint line graphs combined with the SIFT feature matching method is proposed. Firstly, the multi-joint 3D motion data are captured using the Kinect. Secondly, 3D motion data are normalized and distortion data are removed. Therefore, a 2D line graph can be obtained. Next, SIFT features of the 2D motion line graph are extracted. Finally, the line graphs are divided into several regions and then the comparison results can be calculated based on SIFT matching ratios between the tutor’s local line graph and the trainee’s local line graph. The experimental results show that the proposed method not only can easily deal with the several challenge problems in motion analysis, e.g., the problem of different rhythm of motions, the problem of a large amount of data, but also can provide detailed error correction cues.

Based on the density functional theory method, the ab initio calculation with GGA+U was performed to investigate the electronic structure and properties of W-doped TiO2. The results indicated that W-doping induced ferromagnetism and shifted the absorption spectra to visible light region. The ferromagnetism derived from the spin-split of O 2p and W 5d caused by p–d orbit hybridization. Several impurity bands under the conduction band decreased the band gap.

In the paper, the design scheme of the new cold store is proposed firstly, with the consideration of the latest technology application and the convenience and maneuverability of practical teaching. Then the refrigeration system is designed based on the calculation of the heat load of the cold store. The suited components such as compressor, evaporator, condenser and expansion valve are selected and the electrical system is designed. After that the whole unit is installed and adjusted to make sure that the installation is propitious to improve the system performance and convenient for training. Finally the thermal performance of the new cold store system is tested and compared with the old system test. The result shows that the matching of the new refrigeration system is reasonable and the new cold store is up to the mustard. With the help of training on the cold store, the students will meet the essential requirements of STCW 78/95 convention on application and management of the marine cold store.

In this paper, a method to generate the humanoid robots gait intelligently is put forward to solve the problem of poor performance of robot walking. The key idea in this proposed method is to adapt the transmutative humans gait to robot walking. Firstly, the character of the humans gait is acquired by researching a mass of gait data. Then, the typical gait signal is obtained which can be used to generate various gait signals. Finally, this method is proved to be effective by comparing the nature signals and the signal which is obtained by this method.

By using outlier data mining, this paper studied customs risk management in China. Our research contents are summarized as follows: First, we study the status of Customs risk management and we study other scholars’ research of the outlier data mining. Second, we introduce index of outliers and we use outlier data mining to establish a risk estimation model. Finally, we test the affectivity of this model by empirical analysis.

As the aviation has realized the seriousness of pollution and emission issues, people have taken efforts to use renewable energy on planes or UAVs. This paper focused on the applications of solar and hydrogen energy to UAVs. A hybrid power system, consisting of solar cells, fuel cells and lithium batteries, was discussed. To achieve the hybridization of power sources, a prototype of a power management unit (PMU) was fabricated. After the installation of a test system for synthesizing power sources, PMU and load, a series of ground tests were executed to verify the mathematical model of lithium battery and the reliability of the hardware. Ground data confirmed the feasibility of hybrid power system.

The oil condition monitor asks for wear derbies moving into the oil thin cavity stably which is on wear derbies image collecting apparatus, and reduces some phenomena of the wear derbies, such as roll, deposition and self-lock characterization, in order to enhance the quality of wear derbies image. This paper has first studied about the moving video image of the wear particles in an oil thin cavity. A qualitative research on the movement of the wear derbies, such as roll, deposition and self-lock characterization, has been investigated. Then dynamics of wear derbies is analyzed .The paper presents apparatus to avoid the overlap and jam of wear debris on the basic of the result of dynamics analysis. The oil thin cavity is considered to be laid vertically during the experiment.

As a basic problem of wireless sensor in network applications, coverage reflects the quality effect of monitoring and tracking of the network. In view of the high density of sensor nodes deployment, this article works on the node set selection problem, puts forward two kinds of coverage optimization mechanisms based on weighted genetic algorithm and constrained genetic algorithm according to the genetic algorithm operation of the fitness function generation, and calculates approximately optimal working nodes required in the sensor network fully covering area. The simulation results show that the algorithm can quickly converge to the optimal solution and complete the optimization of node set selection, thereby reducing network redundancy and prolonging the survival time of the network.

It is ascertained that the indicators weight system by the Analytic Hierarchy Process and constructed the model of success-degree evaluation method to execute the comprehensive evaluation for bridge preservation and replacement project based on the existing indicators system of bridge strengthening project with the purpose of success-degree in program evaluation. The success-degree classification of the bridge preservation and replacement project improves the system of post-evaluation for bridge preservation and replacement project through division of great success, success, partial success, most failure and failure. It indicates that the evaluation model is simple to assess and conform to the reality.

In this study, silvergrass (SV) reinforced high density polyethylene (HDPE) composites (WPCs) were prepared by injection molding. The effects of maleated polyethylene (MAPE), slivergrass fibers content on the mechanical, Differential scanning calorimeter, morphologies of WPCs were investigated. It was found that the mechanical properties of the SV reinforced HDPE composites can be improved by MAPE treatment. The highest tensile strength and flexural strength of the composites can be reached with 40% and 50% SV contents at the fixed 8% MAPE respectively. The SV can be the nucleating agent with the addition of MAPE. SEM images of tensile fracture surfaces of treated composites demonstrated better fiber-matrix adhesion.

In the estimation of time delay, there always would not appear obvious peak with the basic cross-correlation (CC). In order to solve the problem of the basic cross-correlation method, this essay represents an improved time delay estimation method based on the generalized cross-correlation (GCC) and combines with the microphone array structure to achieve sound source localization. Finally, the simulation results show that this method could measure the sound source’s location accurately with noise and reverberation, and the distance positioning error is less than 10cm, the direction angle error is below 3°.

Gun tube is a kind of thin-walled circular tube with special use. Its inner surface are loaded serious gas loading of high temperature and high pressure gas when consecutive shooting. In this paper, the assault rifle gun is taken as the research object and the FEM software ANSYS is taken as a computing platform, data of barrel dynamic temperature and stress under continuous loading are obtained. The calculation results show that, (1) The temperature field and stress field coupling effect is very obvious in the barrel bore surface; (2) Thermal shock has obvious thin-layer effect; (3) The thermal stress caused by heat load significantly higher than the bore pressure produced by chamber pressure .Model and analysis method used in this paper provides an important reference of design for the design and improve of the barrel in the aspect of heat intensity.

Particle swarm optimization algorithms have lots of advantages such as fast convergence speed, good quality of solution and robustness in multidimensional space function optimization and dynamic target optimization. It is suitable for structural optimization design. In this paper, manual transmission gear train of a tractor is taken as research object, the minimum quality and minimum center distance of the gear train is taken as optimization goal, the gear ratio, modulus, helix angle, tooth width and equilibrium conditions of the axial force are taken as the constraints, a multi-objective optimization model of the gear train is established. The optimal structure design programs and Pareto optimal solution are obtained by using particle swarm optimization algorithm.

The paper presents the numerical investigation of a radial flow centrifugal pump with 2D curvature blade geometry. The geometry is based on the experimental equipment by Anagostopulos. Single phase (water) flow is modeled with a normal mass flow rate and rotation speed. Pressure distribution and fluid streamlines are evaluated and visualized. An extension of the model to transient flow and two-phase flow simulation has been done to see the effect of impeller rotation and gas entrainment in the centrifugal operation procedure.

In order to study the elastic-plastic mechanics properties of the stainless steel reinforced concrete columns under low-cyclic load, the engineering open-source earthquake simulation system OpenSees is used to carry out the numerical simulation. The comparison between the computed results and the pseudo-static test results shows that the OpenSees may stimulate the mechanical properties of the stainless steel reinforced concrete columns by using the fiber element model, both of the skeleton curves and hysteretic curves are well agreement with the tests results.

In this paper, the repeated dropping impact tests of transporting packages of crown pear were implemented to study the cushion performance of the corrugated papers, which used as the buffer liner, including three-storey , five-storey and seven-storey corrugated boards. The results show that there are three stages in the process of peak acceleration varied with the impact cycles, and the repeated impact strengths of transporting packages of the fruit obviously increase with the increasing wall number of cushion boards.

Driving behavior research is the hot spot in the field of transportation nowadays owning to the stern traffic safety. The visual perception model based on bounded rationality has incorporated the attention distribution and concentration; driving fatigue; driving experience and visual information retrieve which provides a vivid simulation of real driver’s visual perception procedure and it lays the foundation for the study of driver’s decision and manipulation behavior.

In this paper, we propose an interactive remote control system using image processing technique for three dimensional displays. In order to control three dimensional displays, we present an algorithm based on gestures recognition. Then we adopt cell-based design flow and 0.18μm TSMC single poly and six metals processing to perform the system chip. Besides, the SMIMS FPGA development board is used to achieve the system. The results prove the performance reaching the well quality of interactive remote control system for three dimensional displays.

Three specimens with ribbed stainless steel rebar and one specimen with ribbed ordinary steel rebar are tested concerning the strength degradation and energy dissipation of stainless steel reinforced concrete columns. The tests results indicate that the damage of the specimens exhibit ductile failure characteristics, and the reinforced concrete columns with stainless steel rebar damage to a lesser extent, appear good ductility and energy dissipation. The strength degradation of stainless steel reinforced column with high axial compression ratio is quite obvious, and with the increasing of the stirrup ratio of column with stainless steel rebar, the strength of column is enhanced.

In order to get the seismic active earth pressure with the mode of translation, adopting some related assumptions of the M-O theory, this paper establishes the first-order differential equation of the Seismic active earth pressure by horizontal slices analysis method and gets the solution of the seismic active earth pressure by boundary conditions. This formula can solve the distribution of the seismic active earth pressure is nonlinear along the wall, the point of application of the dynamic active thrust which is the advantage of this formula and announces the decreasing process of the filling’s rupture angle with the increase of the horizontal peak ground acceleration (PGA) , as well. The rationality and validity of the formula is confirmed by the comparison between the results of the shaking table tests and the formula, respectively. If the retaining wall takes place the mode of translation, the point of application of the seismic active thrust ranges between 0.4 and 0.5 times wall’s height at the horizontal seismic peak ground acceleration (PGA)

Referred the vehicle-track coupling dynamics theory [1] and the vertical dynamic analysis models of Bridge-Subgrade transition developed by Zhai [2] ，Wang [3] and others [4]. This article takes account of the interaction between different structural layers in the subgrade system further by using the dynamic ballastless track model and finally establishes a space dynamic numerical model of the vehicle-track-subgrade coupled system. The dynamic response of the coupled system is analyzed when the speed of the train is 350km/h and the transition is filled with graded broken stones mixed with cement of 3%. Results show that the setting forms of Bridge-Subgrade transition have little effect on the dynamic responses, so designers can choose it on account of the practical situation. Due to the location away from abutment about 5m has greater deformation; the stiffness within 5m should be designed alone. Based on the study from vehicle-track dynamics, we suggest that the maximum allowable track deflection angle is 0.9‰ and K30190Mpa within 5m behind the abutment.

Shock load spectrum of elastic support gearbox is confirmed by Federation Wehrmacht vessel construction rules BV0430/85 standard, and convert into equivalent double-triangular wave acceleration shock load. We take one elastic support gearbox which used in a vessel as computational study subject. With the help of ABAQUS software, we establish finite element model of elastic support gearbox and put double-triangular shock load into finite element model. Taking finite element analysis method do time domain response characteristics numerical simulation research of elastic support gearbox with limited bit and unlimited bit design, respectively, under shock load effect.

The dynamic model of gear driving system is built using centralized mass method in this paper. On the base of frequency domain and time domain results of model derived from equation of Fourier series, the example of a certain gearbox is calculated. Through adjusting the parameters of modulus and tooth number of gearbox, the dynamics computation is completed. The relationship between diversification of modulus and tooth number of gear and vibration noise is gained by comparatively analyzing the calculation results.