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In order to solve the problem of automatically picking up balls in table tennis competition and training, from the angle of machine vision, integrating embedded technology, image processing techniques, measurement and control techniques, etc. and based on the third party base OpenCV and Qt, we designed a automatically picking up table tennis system. Collect video signal through camera to have analysis and process and judge the position of table tennis, then control the trolley and manipulator to pick up the ball and send to the designated spot.

To reduce the number of inter-disturb access points and the interference among access points in same channel, with research on interference issus and channel assignment algorithms of wireless local area network, a scheme suitable for centralized wireless local area network was proposed aiming to minimize the total interference among access points, which comprehensively considerate the number of neighbor and the received power. And then the algorithm with cases was simulated and analyzed, the result of NS2 simulation indicated that the algorithm was simple, effective and feasible, which could realize dynamic adjustment to the wireless LAN RF channel and had a better load balance effect among non-overlapping channels.

In order to meet the large-scale promotion of household heat metering in north China and respond positively the call of the national “Twelfth Five Year” plan for energy-saving and emission-reduction,the design combines the advantage of the cloud computing and cloud software and presents the overall structure of management system based on the cloud computing. Then, the paper focuses on the design of upper computer software and database[1], The upper computer software consists of two parts,one is automatic meter reading software,which is communicated with every collectors by GPRS; the other is cloud software, The cloud software improves the current heat management system by combining the smart home service concept and provides personalized services for many heating companies and vast number of families[2].

Ion Mobility Spectrometer (IMS) is an effective instrument for detecting narcotics and explosives. Signal average IMS (SA-IMS) is used widely because it is relatively convenient to build. SA-IMS is low efficient in utilization of sample ions (1%), while FT-IMS is relatively high (25%). However, detailed discussions of several important parameters, such as frequency sweeping range, frequency sweeping intervals and gating function distortion, have not been made in previous studies. In this article, we build a numerical simulation model of FT-IMS, with which we appraised these parameters respectively. Main job of this article is done with MATLAB. We also propose several guidelines in building FT-IMS.

This article uses the extenics and fuzzy hierarchy analysis method,on the slope stability analysis method of uncertainty is improved.At the same time,on the measured data report AnTaiBao open-pit mine for practical engineering,using the method of the north, a risk evaluation is made on the stability of slope area.Through the engineering example of calculation shows that,in this paper, the risk evaluation method is reliable and can be used to guide the slope mining design.

This article analyzed typical mountain cave dwelling buildings in an architectural perspective, which in Zhang Jiata Village in Fangshan County Luliang city Shanxi province on the basis of surveying and mapping the field, extracting its landscape elements and qualities and the eco-gene, summarized the value features and protection analysis of ancient village.

Wide-Chord Hollow Fan Blade is One of the New Technologies Used in Aircraft Engines. in this Paper, the Modal Analysis Method is Used to Analyze the Influence of the Rib Number and the Rib Thickness to Wide-Chord Hollow Fan Blade Vibration Characteristics. the Result Shows that the Wide-Chord Hollow Fan Blades Greatly Improves the First-Order Vibration Frequency Compared with the Solid Blades, and the First-Order Vibration Frequency of the Wide-Chord Hollow Fan Blades is Reduced with the Increasing Rib Number which is Not Good for Vibration Elimination. the Wide-Chord Hollow Fan Blades’ Vibration Frequency Changes a Little when the Rib Number is Larger than Three. in Addition, the Rib Thickness has Smaller Effect on Wide-Chord Hollow Fan Blade.

Harbin metro, the first engineering is in the process of being built. Metro tunnel is supported by reinforced concrete structure. Commonly used model is used in design of shield tunnel liner. In this paper, the habitual model is improved. The joint of model of the habitual model is improved and the endogenetic force formulas for the new model are derived. At last, the derived formulas and the existing formulas are validated by Harbin first metro. According to the research result, we can know the formulas derived in the paper are credible and they have academic practical meaning for design and construction of the subway liner.

The paper introduces some information about Harbin Metro line 1, makes the decision analysis on economies, environment, society and geological environment of Harbin Metro line 1 by some fuzzy comprehensive evaluation model, and gives the weight coefficients of indicators through analytic hierarchy process. The comprehensive evaluation result provides the basis for decision-makers during decision of metro projects.

Deformation of segment and rock is one difficult question of the subway design. When building the calculation model of the liner we mainly think about the effect on the liner of the joint and the resistance force of the earth. In this paper the joint of the model of the used model is improved and the inner force formulas for the new model are derived. At last, the derived formulas and the existing formulas are validated by Harbin Metro Line 1. According to the research result, we can know the formulas derived in the paper are credible and they have academic practical meaning for design and construction of the subway liner.

In order to restrain harmonic pollution of power grid, the structure and control strategy of APF was researched. The structural parameters and method of direct current control of the most widely used APF with three-phase VSI was discussed. Decoupling control of active and reactive current on the dq plane was realized by dq transforming. Harmonic of load current was detected by Ip-Iq algorithm based on the instantaneous reactive power theory. Double closed-loop control was applied and PWM drive signals of IGBT were got through comparison of triangle wave and modulation wave. The simulation results demonstrate that the kind of control method make APF good dynamic response and static compensation.

Considering the functional requirements of essential service, value-added service, prediction service and personalized service, which are demanded by users from university, enterprise and government, this paper designed an infrastructure of university information service platform using data warehouse technology. By means of the infomation resource integration method put forward by this paper, the platform realized the subject-oriented, multi-scale service to meet users service requirements and support decisions.

In this paper a new support structure was given to solve the problem met in the force measurement with engine jet. The force measurements of waverider were undertaken in the hypersonic wind tunnel. The test condition was at Ma=6, angle of attack α=-6°-6°, at which we researched the effects on the vehicle aerodynamics of inlet cowl opening and closing, support system, engine jet, and pressure ratios. To decrease the effects of strut on the jet flow-field, we took sharp belly strut to support the model in the wind tunnel. The belly strut could support the waverider model, force measurement balance, and it could make the inlet flow set up, and provide the high pressure jet. The test results showed that the belly sharp strut had little effects on the flowfield and could inject the inlet flow, and could provide very high quality jet.

Geometric Dilution of Precision (GDOP) value will become larger when the number of visible satellites is less than four or the geometry of satellite constellation is poor, a GDOP Chimney Peak phenomenon is also easy to emerge [, the positioning accuracy of GPS receiver will be affected seriously. A vector-based tracking loop GPS/INS receiver design method is proposed in this paper. The current position of receiver is given by INS, Line-of-Sight (LOS) unit vectors between receiver and satellites will be built, which are transmitted into vector tracking loop, the relationship between LOS and GDOP is introduced in detail. Pseudorange and pseudorange-rate are used as measurements to design navigation filter. The simulation results demonstrate that proposed vector tracking method can avoid GDOP Chimney Peak phenomenon, position Root Mean Square error is less than 10 meters.

In order to improve design reliability of wind turbine, it is needed that calculating method of aerodynamic load during wind turbine run. In paper from the angle of the project, NACA special airfoil of wind turbine is analyzed. Combined with thin-theory, airfoil angle of attack variation is deduced, meanwhile wind turbine actual force is calculated in each blade location point when blade of wind turbine is running based on wind shear theory and tower shadow effect. According to actual condition calculation method is engineering amplified, aerodynamic load calculation method of wind turbine blade is obtained. By this method aerodynamic load which is calculated match with experiment result, it fits better.

Aircraft communication and satellite link handoff issues in spatial information network are very important and are focused in this paper. The simulation modules of satellite network nodes and links in network simulator version 2(NS-2) are analyzed in details in this paper. A method of extending NS-2 kernel module is proposed based on analysis of satellite network simulation principle and approach. As an example, the aircraft communication simulation module is designed and implemented. Simulation results show that flight of aircraft has effect on the link handoff characteristic, and show that the proposed extension method is feasible.

The over-head transmission lines will gallop because of the natural conditions, which will cause serious incidents. In order to avoid the galloping of the over-head transmission and improve the effect of transmission system, some analyses are done about the formation mechanism of transmission lines galloping and the current anti-galloping devices. On the basis of the reactive mechanism of swing, the active anti-galloping mechanism is presented. Besides, the mathematical model of the anti-galloping system is raised. With the theoretical calculation and numerical simulation for the conductor which is equipped with active anti-galloping device, the result is feasible. The paper introduces the structure of active anti-galloping, which lays the theoretical and practical basis on the realization of anti-galloping.

Ce0.5Ti0.5O2 ion storage films were prepared by using sol–gel routes employed butyltitanate（Ti(OC4H9)4） and cerium nitrate（Ce(NO3)3•6H2O） as main initial materials. Structural, optical and electrochemical properties were investigated by XRD, SEM, cyclic voltammetry curves and utraviolet visible spectroscopy in this work. Ce0.5Ti0.5O2 ion films contained crystallization CeO2 and amorphous TiO2, and had large ion storage capacity. Its injection of charge density was high to 12.01 mC•cm-2 and K value was 0.75. It had better cyclic reversibility and high transparency, which kept colorless and transparent during the whole injection and extraction process of Li+. Light insert ion storage films of Ce0.5Ti0.5O2 has important significance in the preparation of electrochromic device.

With consideration of the actual requirement of fault knowledge management in current aviation maintenance, ontology-based knowledge representation method of aircraft fault is studied. Knowledge sources of aircraft fault ontology are analyzed based on ontology modeling primitives. Ontology construction method of aircraft fault knowledge is proposed learning from software engineering and the essence of the existing ontology construction methodology. On the basis of the above study, aircraft fault ontology which is consist of Fault Core sub-ontology, Product domain sub-ontology, Case domain sub-ontology, and Diagnosis domain sub-ontology is build, and it represents aircraft fault knowledge completely and consistently, and also lays the foundation for knowledge management of aircraft fault.

The force generated in and required for the sealing process of the first seal of elliptical cans was analyzed based on the energy conservation theory, corresponding formulas describing the sealing-force were derived, and the factors affecting the sealing-force were discussed. This provides a theoretical basis for the design and optimization of the roller curve as well as for further study and calculation of forces in the sealing process of various abnormally shaped cans.

Tall buildings play an important role in the modern urban city, where only a few lands are available for the increasing population. In this study a hybrid genetic algorithm (GA) and optimality criteria (OC) method is presented for the optimum design of tall buildings under multi-load cases based on the current Chinese design codes. The entire optimum design procedure is divided into two parts: strength optimum design and stiffness optimum design. Member depths are treated as design variables. A GA with the strategy of adaptive feasible region is proposed to perform the discrete optimization of tall buildings under the strength constraints with the results of the stiffness optimum design as the lower bounds of the member size. The optimum stiffness design is conducted using OC method with the results of the strength optimum design as the lower bounds of the member size. This procedure is repeated until convergence is obtained. A design example is optimized to demonstrate the practicability and effectiveness of the proposed method