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Bearing sleeve, as one of important parts of bearing structure, determine the bearing performance directly. In this paper, based on the ball joint structure, the tribological properties between Polyoxymethylene (POM) and 40Cr are studied with Ring-Block method. The effects of friction velocity and applied load on friction coefficient are tested and analysed, the analytical model in friction force, friction velocity and applied load are created, which will provide useful technical data to the application.

Spinel Li4Ti5O12 (LTO) doped with Mg2+ was synthesized by solid-phase reaction method. The Mg2+ doping quantity was 3%, 6%, 9%, and 12%, respectively. The structure and electrochemical performance of the prepared LTO composites were investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and galvanostatic charge-discharge tests. It was found that the doped Mg ion did not change the structure of Li4Ti5O12, and it was evenly distributed around Li4Ti5O12. When Mg2+ doping quantity increased from 3% to 12%, the internal resistance and charge transfer resistance of the composite both decreased. The first discharge specific capacity of 6%-Mg2+ doped LTO composite was 168 mAh/g, which was close to the theoretical capacity of pure lithium titanate (175 mAh/g), and the capacity retention rate was 98% after 100 cycles.

Aluminum ball joint is an advanced structure using to connect steering parts with the merits of simple and lighting. Usually extrusion strength and torque are the most important parameters to evaluate the ball joint properties. Generally, the ball sealed in the Aluminum housing by forming method which has an impact on the extrusion strength and torques. So how to control the forming and achieve the best properties is very important. In the paper, the relations between housing dimension and strength, torque are studied; the influence of forming on torque is researched. The rules in them are achieved.

Based on the selenium ion beam assisted magnetron sequential sputtering technology, low temperature deposition of CIS thin-film solar cells in high quality can be achieved. By comparing with the method of conventional gas phase atomic deposition, and through simulated analysis from the perspective of diffusion uniformity, numerical calculation on the depth of ion beam injection is proceeded. First, according to the classical collision theory in molecular dynamics, the theoretical calculation on the process of ion implantation is done; the concentration distribution of implanted selenium ions can be got by using TRIM program for simulation analysis. On this basis, the concentration distribution of selenium ion after diffusion can be further obtained. Finally, the calculation model is established; through comparison and analysis, when the selenium diffusion uniformity is same in the both conditions, the substrate temperature T1 needed for ion beam assisted deposition and the substrate temperature T2 needed for gas phase atomic deposition are respectively calculated. The calculation results show that on the premise of merely considering the depth of implanted ions, from the perspective of the diffusion uniformity, the selenium ion beam assisted deposition technique can obviously reduce the substrate temperature comparing with traditional vapor deposition technology.

The rapid prototypes of different printing temperature by Objet30 Stratasys Pro printer were found a certain difference in performance in the process of using the process.In order to studied the effect of printing temperature on the rapid prototyping of photosensitive resin, tensile and bending tests were carried out on the rapid prototyping parts at 12°C, 18°C, 21°C, 23°C, 25°C, 30°C,respectively,and the rigidity and surface roughness of rapid prototyping parts were measured.Research shows：the tensile strength increases with the increase of printing temperature , tensile elastic modulus fluctuates with the printing temperature , they all increases rapidly after 25°C;The bending strength increases proportional with the increase of printing temperature, and the bending modulus increases first and then tends to decrease with the increase of printing temperature;The hardness value increases slowly with the increase of printing temperature, and increases obviously after 20°C,the hardness value in the middle of the prototype parts is bigger than the edge parts；The surface roughness with increasing printing temperature, although it is floating up and down, but have little effect.

Since 1980's, all the developed countries have built up national computer network of education and scientific network, which have been the most important infrastructure of education and scientific research in these countries and facilitate their development. China began to invest in building Cernet (China Education and Research Network) since 1994.Many colleges and universities have set up their own campus network. Liaocheng University set up their own campus network in 1997. In order to ensure high availability, high stability and high security of campus network, network information center staff conducted a lot of practice to explore, finally we find some way for Liaocheng University.

With the popularity of the Internet and the rise of mobile Internet application, the Internet finance is growing rapidly. The Internet finance includes online shopping, mobile payment, online financial management etc. However, there exists security problems in third-party payment, online shopping, online banking, mobile payment, etc. In order to solve the security problems with Internet finance, on the one hand, government should establish and perfect law and regulation systems, standardize network security technology, strengthen the network supervision, and make more effort to crack down Internet crimes; on the other hand, Internet users need to enhance network security awareness, and network security researchers should provide methods and countermeasures to prevent the online frauds.

CIGS thin film solar cells on polyimide substrate was a significant developmental direction of solar cells and fabricating high quality CIGS thin film in low temperature was its pivotal technology. The development of manufacturing the CIGS thin film solar cells on polyimide substrate in low temperature was described. The specific principle, manufacturing technique and application prospect were also involved. The problem should be solved in the future progress of CIGS thin film on polyimide substrate was illustrated.

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.

Researches on health monitoring technology of concrete structures by using piezoelectric smart aggregates have achieved a great development. However, the technique is not widely used so far in practical engineering. Because when constructing large-scale structural health monitoring (SHM) system using wire-based sensors, it requires a lot of cables to form a monitoring network, resulting in huge cost of abundant material of wires and labor for wire placement, and the relatively heavy maintenance work in case of failure of the SHM system. A kind of wireless sensor network based on the protocol for Zigbee802.15.4 and the passive piezoelectric smart health monitoring technology is developed in the paper. Through internal load monitoring tests of a concrete bridge model under impact loading, the developed wireless smart aggregate (WSA) health monitoring system is experimentally validated. The finite element method (FEM) is used to simulate the process as the same as the bridge model test, and the numerical results are consistent with those of the experiment. The experimental results show that the developed wireless system is stable and reliable, and can be applied in concrete bridge structure health monitoring under impact loading.

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 cost of public rental housing depending on the view of life-cycle has been studied. The construction project life-cycle cost management paradigm consider both of the cost in construction period and the cost in operation period was proposed. The proposed construction of projects cost includes not only the cost of funding sense, should also include environmental costs and social cost. By reducing life-cycle cost of public rental housing, maximize the project value, so the economy and people's livelihood can truly improved.

Torque converter turboshaft is a hydraulic mechanical transmission devices of key components. In a new-mounted hydraulic mechanical transmission, super heavy laden vehicle during the test, the torque converter turboshaft fracture occurs when the vehicle traveling to 13 00 km, resulting in transmission power interruption, chassis parking problems. To achieve accurate positioning of the torque converter turboshaft fracture failure reasons, this paper analyzes the means of optical microscope and scanning electron microscopy, carried out on the fracture failure analysis, then using classical and finite element method to calculate the turboshaft intensity of the strength, and proposed optimization improvement program based on the cause of failure.

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.

Partial interference alignment (PIA) strategies for the K-user interference channel are considered. Two schemes are proposed to align the partial interference for the downlink interference channel in the case ofK>3. In the first scheme, strong interferences are limited as much as possible by aligning the two strongest interferers into a same subspace at the receiver. While the second scheme is to design its precoding matrix (or vector) by selecting the precoder pair which maximizes the chordal distance between designed signal subspace and interference signal subspace in the set of pecoding matrices (or vectors) at each transmitter. Simulation results show that compared with the existing schemes which don’t optimize the precoder, such as Fixed-PIA, the proposed schemes can improve the sum rates significantly by selecting IA forms in multi-input multi-output (MIMO) systems.

In this paper, we analyze and point out several weaknesses in the dynamic ID-based remote user authentication schemes using smart card for multi-server environments, and present the countermeasures to enhance the security of the schemes. Taking Li et al.'s scheme for instance, we demonstrate that their scheme does not provide forward secrecy and key privacy for the session keys, and cannot resist offline password guessing attack. Furthermore, the reasons of these security weaknesses are analyzed through extending the attacks to its predecessors. Finally, the improved ideas of local verification and authenticated Diffie-Hellman key agreement are presented to overcome the weaknesses mentioned above.

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.

In order to obtain the sheet metal anisotropy under wide strain range, plane strain compression method with laminated samples is investigated. In the experiments, two laminated samples are introduced, sample 1 is deformed at rolling and thickness direction, and sample 2 is deformed at rolling and transverse direction. In the paper, the ratio of deformation forces obtained from sample 2 (p2 ) to sample1( p1) is used to assess the anisotropy of sheet metal, and verified by analytical method. The results show that the ratio of p2top1 is the function of anisotropic index r, and the anisotropic assessment by this method has a good agreement with that obtained by universal uniaxial tensile test at uniform deformation.

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.

For testing the quality of radar echo propagation, the reverberating chamber electromagnetic environment is classified, the quality of radar echo propagation environment emulation is estimated by the parameter S, the Rice factor K is compared with the parameter S, the test result illustrates that the reverberating chamber can be used as emulator of radar echo propagation environment and as emulator of the base of radar electromagnetic environment.

At present, few architects explore deeply architectural essence. Jacques Herzog and Pierre De Meuron keep chasing the essence of architecture. This paper will analyze their works, and find their exploration of architecture essence on architecture structure, space as well as form.

In order to improve the sense of cooperation of robotic fishes between each other to complete the task with high efficiency, this paper presents a path planning method for multi-robot fish based on the cooperative game model. With a mathematical model established on the cooperative game which is based on the game theory, the robotic fish in this system corresponds to the other participants in the game, benefit function of the game player on the cooperation model of multi-robot fish path construction is studied in this paper, which gets system Pareto optimal solution, then getting the optimal path of the entire system. Using the above method, the authors simulate and analyze on the robotic fish in water 2D simulation platform, and to use Matlab to simulate robot fishs track. The results of analysis indicate: Applying the path planning theory in the multi-robot fish movement system is effective and feasible, and that avoids planning only a single robotic fishs optimal path in the system, while leaving the movement of system in the beneath coordination.

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.

Hybrid system is a whole system in which the discrete part and continual part interact each other. It discusses the definition and the character of the hybrid systems. Then the hybrid characters of the traffic and transportation system is described. It sums up the hybrid system methods of studying transportation system, points out the shortcomings of the current studying methods and forecasts the future studying fields and methods.

One direction of the cross wedge rolling technology is to realize high-efficiency, precise and near-net-shape forming hollow axle with multi-wedge synchrostep cross wedge rolling. This paper deduced the rotated condition of forming hollow shaft with multi-wedge cross wedge rolling (MCWR) base on forming solid shaft with single-wedge cross wedge rolling, and analyzed technics parameters on the influence of rotated conditions. Through the finite element simulation we got rolling technics parameters on the effect of rolled piece and selecting principle, and then created the 3D model of the equal diameter period of hollow axle with the MCWR. By using DEFORM-3D software, the process of rolling equal diameter period was simulated. The result indicated that it is feasible to roll hollow axle with multi-wedge synchrostep by cross wedge rolling.

SolidWorks is a popular 3D design software．The characteristics and developing methods of SolidWorks which 3D design software are introduced, and studies the process of parametric design on SolidWorks software by using VB programming language, as well as the technologies of elaborating the program with API functions. And then combine with the crampoon elaborating the principle of process-driven method. When designing the large crampoon, we use the parametric design method to auto-form the 3D target crampoon model by constructing a interface software protype with which the crampoon demension parameters can be converted into some related program variables. That method not only improves the crampoon design efficiency and accuracy, but also provides some useful referenced experience to parametrical system design of other parts. Parametrization design has a wide application prospect in the field of mechanical parts designing.

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

In this paper, the intelligent vehicle control system’s design based on HCS12X MCU.The Multi-sensor combination technology be used in this control system. This system can control vehicle's position and Navigate the vehicle with GPS, vision sensor and laser radar sensor. This control system have an optimal decision in safety, reliability and handleability. The experiment showed that the smart vehicle can driving in the designed road by itself.

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.

The limiting facts of driving the Hall element by the pulsed power supply and sampling when the peak value coming are studied. The equivalent relation of temperature rising between the DC and pulsed power supply is given. When the electric field intensity inside the Hall element rises to about 1850V/cm, the linear relationship between the Hall output voltage and the input voltage will be affected by the decrease of the mobility. The thermal-power consumption almost does not affect the use of the Hall element. The above problem could be overcome by enlarging the die dimension.

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.

The Inverse Synthetic Aperture Radar (ISAR) is a high resolution imaging radar. Some methods used to evaluate the jamming effect of general radar are unsuitable to ISAR. Considering the principle of radar jamming and the theory of image disposal, the paper gives a new evaluation method of barrage jamming effect on ISAR, it evaluates the jamming effect through calculating the difference of two picture’s Moment Invariants, and this method can reflect distortion degree of the jammed target during the whole jamming process. The results of simulation prove the method is corrective and effective.