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In order to eliminate cracks in the chromium coating, a novel method named flexible extrusion assisted chromium electroplating was proposed. The bright and crack-free chromium coatings were electrodeposited by using the perturbation and extrusion of hard and insulating particles. The prepared deposits were characterized by scanning electron microscope (SEM) and three-dimensional topography. The testing results showed that the surface was very smooth and there was no micro cracks in the coating. Micro hardness of the electrodeposited layer was also tested. It was confirmed that the chromium coating electrodeposited with rotating cathode in hard particles had high micro hardness as to 850HV and the micro hardness could be controlled by the process parameters. The rule of the micro hardness was concluded by analyzing current density and rotating speed. In addition the results of salt spray test and electrochemical polarization curve showed that the coating deposited by new method had higher corrosion resistance than that by traditional method.

SOX emission control of the marine exhaust gas can be achieved by post-processing desulfurization and LNG’s usage. The two solutions are discussed by the technical and economic analysis. Four kinds of post-processing desulfurization have the differences on system composition, wastewater discharge, and applicable waters, absorbents and so on. The pay-off periods of post-processing desulfurization are ranged from 0.5 to 2.2 years, which depended on the ship type’s difference. LNG’s pay-off periods is about one year, but some hidden costs for LNG ship’s promotion are difficult to estimate.

Based on analysis of the mathematical model of the brushless DC motor (BLDCM), a method for modeling and simulation of BLDCM speed control system is developed in this paper. The simulation model of BLDCM could be established by combination of the functional blocks and S-functions in MATLAB/SIMULINK. In the double loop of control system, a PID controller was adopted in the speed loop and a current controller was completed in the current loop on the principle of hysteresis current track PWM inverter. The modeling method has merits in rapidity, practicality and has guiding significance to designing actual brushless DC motor control system.

The alterations of the water level in the middle reaches of Yangtze River were investigated using the range of variability approach based on daily water level datasets extracted from 5hydrological stations.Results show that the operation of the Three Gorges Dam disturbed the hydrologic regime downstream and directly affected the water level to some extent. The rate and frequency of water level changes was most altered, while the timing of annual extreme water level was least affected. For the overall degrees of hydrologic alteration, high degrees were identified in Yichang (56%) and Jianli (47%) reaches; moderate degrees in Hankou (45%) reaches; and low degrees in Chenglingji (37%) and Luoshan (40%) reaches. Water level alterations in the middle reaches of Yangtze River were mainly caused by human activitiessuch as dam construction in the upstream and in-channel sand dredging, and also natural hydrological processes.

This paper simulated the microvibration response of a micro-electronic workshop by using the finite element analysis software Sap2000. Based on the measured vibration signals as input data at the base, the displacement and velocity curves at some typical points on the work platform of a micro-electronic workshop under uniform and multipoint excitation were obtained. The results show that displacement responses at nodes of beams or in the direction of lower stiffness under multipoint excitation are much greater than those under uniform excitation, while there are no marked difference in the peak values of velocities.

An H-shaped steel frame in fire combined blast loading was numerically developed in this paper using finite element method by ANSYS thermal analysis. At the first step, a temperature field has been numerically analyzed. At the second step, each element of the steel frame was assigned different modulus of elasticity and yield stress based on the temperature analysis results. A dynamic simulation of the steel frame subjected to a blast load was analyzed under such a temperature field. The failure modes of the frame structure has been discussed. Finally, a same shape frame at the room temperature under the same blast load was simulated to compare with that at the elevated temperature.

The trend of climate change in Jianghan and Dongting Plain is obvious. The trend of climate change and its impact on the wetland were got through the unitary linear recursive analysis and Pearson correlation analysis. That the air temperature is becoming higher made the algal bloom happens earlier. The precipitation has a significant negative correlation with the exposed days of bottomland. Meanwhile, the exposed days of bottomland has a positive correlation with the air temperature. The trend of climate warming has impact on the distribution, migratory route and breed time. The biodiversity decreased in the Jianghan and Dongting Plain.

Using a CFD software, the numerical simulation of a 2×300MW direct air-cooled unit is done by multi-stage modeling method. the effect of the environmental wind on the heat-exchanging performance of the air-cooling island is analyzed by numerical simulation. The effects of different wind velocities and directions on exterior flow field and heat-exchanging efficiency are analyzed. The reasons of hot air recirculation and the decrease of the fans’ output are found. The heat transfer performance of air-cooled island is affected after the installation of windproof net. The result shows that the form of low-pressure area is the main reason for the hot air reflow and the decreace of the fan’s output; An improved flow field can be got after installing the windproof net. The volumetric effectiveness can be increased by 8.5% at a wind speed of 9 m/s.

A centrally reinforced column is a new type of RC columns, formed by providing a reinforcement skeleton at the central part of the cross section of an ordinary RC column. Tests have shown that as compared with an ordinary RC column, this type of columns has a higher load carrying capacity and ductility. From the pushover analysis of a frame composed of ordinary RC columns and one consisting of centrally reinforced columns, their seismic performance under seismic load of 9-degree intensity was studied according to Chinese code, including target displacements, story-level displacements, interstory drifts, appearance and development of plastic hinges. The results indicate that although the dimensions of cross sections of columns in the frame with centrally reinforced columns are smaller than those of the ordinary frame, the former still has a higher overall load carrying capacity and seismic performance than the latter.

The basic structure of the piston hydraulic cylinder was introduced. A three-dimensional model was carried out for the hydraulic cylinder by using Pro/E soft，the finite element analysis to the largest hydraulic condition while hydraulic cylinder working by using ANSYS soft，and the distribution of the stress and strain of hydraulic cylinder was derived from it. It optimized the structure of hydraulic cylinder effectively and the cost was saved.

In this paper, PC9S12XS128 MCU produced by Freescale Semiconductor Co., Ltd is used as the core control unit to designed a intelligent vehicle, which can be free to follow the line of travel. The main control system including motor drive module, server drive module, the path identification module, power module, etc..Through compare a variety of hardware control program, use the best program to take control of car model’s speed and direction. Experimental results show that the intelligent vehicle designed can antomatic driving on the path of human plan accuracy.

The grain fluctuation situation of Hubei was analyzed by calculating the grain fluctuation coefficient from 1990s. And the quantitative correlation between grain production and the water disaster was studied by grey correlation analysis. The results were shown as follows. The main water disaster factors impacting grain production were effective irrigated area and planting structure, the relationship degree of which with grain yield is respectively 0.91 and 0.85 ranking the first two among all the selected factors. It was shown that water disaster influenced the grain yield heavily

The effects of process parameters such as laser power, scanning velocity and wire feeding speed on weld joint quality has been discussed through some laser welding experiments using coaxial inside-beam wire feeding process method. The results reveal that: Along with the increase of the laser power, weld width and depth are increasing gradually; Coating surface will appear burning loss and deboss when laser power is too large. The increase of scanning velocity decreases the depth and width of molten bath, and abates laser hole-effect, so the metal plate can not be welded penetration. Larger wire feeding speed can avoid welding seam produce burning loss, but it also can strengthen welding wire reflect the laser, and decline the welding.

Microvibration is one of the key factors affecting the normal operation of a microelectronic plant. Such measures as to increase the stiffness or damping ratio to prevent microvibration are easy to implement and low in cost. By using the finite element analysis software Sap2000 to simulate the microvibration performance of the working platform of a typical microelectronic plant, this paper compared some of its microvibration response when there were shear walls with that when there were no shear walls, discussed efficiency of structural stiffness on its microvibration response. The results indicate through the provision of shear walls to increase the stiffness of working platform enlarge acceleration and velocity response of the structure, it can decrease displacement effect.

Bored pile as a major type of foundation, during the construction process, hole collapse or weak air tightness of catheter leads mud layers or broken pile, which makes bearing capacity reduction or even complete loss leading differential settlement of building foundations. In this paper, two-dimensional simulation of the pile has been made by finite element analysis software ADINA. By using of large-scale numerical analysis software MATLAB, the data obtained has been fitted deriving empirical formulas, which researches how different thickness and depth of mud layers impact on bearing capacity of bored piles, having a certain engineering applications.

Based on the pseudo-static test of 6 high-strength RC columns with central reinforcement skeletons, this paper studied their hysterisis performance, degradation of strength and rigidity, and energy dissipation capacity, with the affecting factors analyzed. The result shows that the central reinforcement skeletons can compensate for the low plasticity and brittle failure susceptibility of high-strength concrete so that all the specimens have stable strength, slow rigidity degradation and high energy dissipation capacity at later stage of loading; the larger the core areas the higher the strengths and ductility of the specimens, but slightly faster the degradation of strength and energy dissipation capacity as compared with the specimens with smaller core areas; the spacing of ties, longitudinal reinforcement ratio of core area both influence the strength degradation and energy dissipation capacity of the specimens, but they have little effect on their strengths.