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The T-section aluminum alloy window trim strip sheets are used to improve vehicle appearance. As the mobile scenery line, these window trim strips with claws need high forming accuracy to meet good assembly quality requirement. The top portion of the T-section sheet is stamped to form an edge flange structure. Springback control is essential in forming process. In this paper, the influence of the window trim strip geometric parameters on forming springback is studied. Some finite element models of the process were built with the Dynaform software. The simulation results were verified experimentally. The main conclusions include as belows: The different heights of the stiffeners part in T-section change the stiffness of the part. Although the stiffeners part does not participate in the forming, it also has springback in the forming process. So, it is necessary to study the influence of the flanging part width (W) and the stiffeners part height (H) of the T-section on springback. We set W to 15 mm and change the value of H value according to the real product. The value of springback increases with the increase of H value in the beginning. After ratio of H/W increases to 0.6, the value of springback fluctuates with the increase of H value. When ratio of H/W is about 0.5, the springback values are mostly less than ± 0.5 mm in key sections, which is acceptable.

A robot based on STC12C5A60S2 single-chip-microcomputer is designed for improving the production efficiency and reducing repetitive work. The system could identify path by detecting metal using eddy current sensor. By ways of the single-chip-microcomputer controlling stepper motor, the robot can run according to the predetermined route, judge independently cargo range and deliver the goods to the designated location. The implementation methods of the important links, such as mechanical structure design, path recognition and steering engine driving and so on are introduced, the system of which make the information interaction with computer through ISP-module (In-system-programming).by testing the model, it shows that the system can meet the design goals of handling goods automatically, and it has higher application value of reducing the accident rate of worker in repeated works and improving labor productivity.

The system simulates completely the water polo-game of entity bionic robot-fish, designed and developed based on Microsoft Robotics Studio SDK(MSRS) 1.5, which includes seven modules, such as client strategy, server core control, common interface, environment setting, simulation data display, assistant function, fish robot kinematics modeling and so on. The simulation system simulates the motion of bionic robot fish and the entire process of water-polo-game in real time, and provides simulation testing platform for bionic-robot-fish model optimization, machine fish movement algorithm, and robot fish water-polo-game.

Due to the deflection of tool and workpiece induced by cutting force, there is a high complexity associated with the prediction of surface form errors in the peripheral milling process of thin-walled workpieces. And the prediction of surface form errors induced by cutting deflection is the precondition for process optimization and error compensation. This paper proposes a systematic simulation procedure suitable for surface form errors prediction in peripheral milling of low rigid thin-walled workpiece. Some key algorithms with the judgment of contacts between the cutter and the workpiece, the flexible iterative algorithm as well as the tool/workpieces deflection prediction using FE model are developed and presented in detail. Comparisons of the form errors and cutting forces obtained numerically and experimentally confirm the validity of the proposed algorithms and simulation procedure.

In recent years, the strategic significance of the oceans is growing as well as its research and development needs. The underwater wireless communication is becoming more and more important. The underwater acoustic communication is one of the few mediums which can conduct the underwater transmission over a long distance, and the multipath effect is the major obstacle of affecting the systems high speed and high reliability. The characteristics of underwater acoustic fading and coherent multi-path channel are studied, and the model of underwater acoustic spreading spectrum (SS) communication system is established. The affect of coding technique on the systems performance are analyzed in detail. The improved RAKE receiving technical solution is put forward, whose simulation analysis and data in different combining ways are given. It is proved that the scheme can better solve the problem of multipath interference in underwater acoustic transmission.

A new design method for product family was presented based on adaptable product platform. Firstly, customer demands were analyzed for bridge crane. Secondly, axiomatic design was utilized as framework to zigzaging mapping between functional requirements and design parameters, and design matrix was established. Then the sensitivity analysis among design parameters and between design parameters and functional requirements was done. The design relation matrix was established and relation degree among design parameters was calculated. Based on above analysis, the platform parameters were identified.

The direct digital frequency synthesizing technology is one of the main area for frequency synthesizing technology. This paper proposed an output shift keying (OSK) digital circuit design for a 14-bit 2.5GSPS RF-DDS, which can support two modes: manual OSK and automatic OSK. Simulation verification and test results both show the OSK circuit design can support amplitude modulation.

This paper proposes Bayesian statistical method to identify the video traffic by the symmetrical features and coding statistical characteristics of video calls. According to the problem of high computational complexity of the non-parametric probability density estimate method in the condition of large samples, we propose grid probability density estimation method of gird division to reduce the computational complexity. We present identification results. The experimental results indicate that that this method can effectively detect video call traffic.

It has become a hot research topic that to improve the coordination performance of multi-robotic system by communication. With rapid development of wireless communication and robot technologies, multi-robotic system based on spread-spectrum technology has become product of combining two technologies. Code Division Multiple Access (CDMA) technology is applied in multi-robotic communication system here. According to the modified m-Walsh sequence got by the way of analyzing the relation characteristic of Walsh-code and m-sequence, the best direct sequence spread spectrum (DSSS) PN code and the improved RAKE receiver scheme are proposed, which satisfied the requirements of real-time performance, reliability and confidentiality in multi-robotic communication system, and have great significance for the research of multi-robotic communication system.

Considering the shortcomings of H.264 rate control algorithm, the paper proposed a new frame level of rate control algorithm according to the movement activity of each frame. xperimental results showed that compared to JVT-G012 which adopted rate control algorithm,the proposal can control the rate more accurately and obtain the higher PSNR and visual quality.

7075-T651 aluminum alloy are widely used in aeronautical applications such as wing panels, but there is no corresponding constitutive model for it now. In this paper, the flow behavior of 7050-T651 aluminum alloy was investigated by Split Hopkinson Pressure Bar (SHPB) and quasi-static compression experiment system. The strain hardening parameters were obtained by quasi-static compression experiment data, and the strain rate hardening parameters at various strain rates (1000-3000s-1) and room temperature, and the thermal softening parameter at various temperatures (20-300°C) where strain rate is 3000s-1 were obtained by SHPB experiment data. Then the constitutive equation of 7075-T651 aluminum alloy is obtained based on Johnson-Cook constitutive equation model.

The representation and retrieval technology of components are two core technology of the reusable component library. Related research think that the component query method based on facet description is much better than other methods, but when the user is not familiar with the term hierarchical tree of facet, they can not accurately represent the needs of their inquiry, so lead to lower query precision.To address this problem, this paper proposes a component query method based on facet description .In this method, the component will be expressed as vector form. Through the iterative process, using the user feedback information on the query results to adjust the user query vector constantly, and making it approximate the ideal query vector. Through the related experiments, this method is proven to improve the effectiveness of the component query precision.

Direct Sequence Spread Spectrum (DSSS) Communication has been widely applied in Personal communications network, WLAN, the third-generation mobile communications, satellite communications systems, military tactics communications and etc, thanks to the DSSS signals’ strong anti-interference ability, low probability of being intercepted and outstanding multi-access communication ability. At the same time, the Problem of estimating Signals has been of great research interest with the development of wind-band weak signals processing and communication antagonism. A new effective detection method of DSSS is proposed, combined the method of wavelet transformation with cycle spectral correlation approach, from the perspective of jamming in non-cooperation condition, and a simulation result of signals--BPSK is given.

Design the 3D pattern of jacquard fabric which can be produced as wall covering, we found that choose decentralized irregular image and make the image deformation is not obvious; floating length can’t be too long and tightness are almost same everwhere to make the fabric smooth; when match designing, rendering algorithm must be from the center to keep the two sides from deformation; the weight and length of the pattern should be design base on the image to make the joint invisible.

Drying plays an important role in the post-harvesting process of grain, and the quality of the corn after drying has received an increasing concern. The mathematical model of grain drying plays an essential role in developing grain dryer structure and obtaining the drying technological parameters. Furthermore, an accurate mathematical model is a reference for automated control during drying process. In this paper, using mathematical models and quality model of the corn drying process, a digital simulation of corn drying machine system based on a virtual instrument was established for 5HSZ dryer. Finally, an on-line measurement and automated control software of grain parameters were developed providing the changes of moisture, temperature, humidity, and germination rate in the process of drying. The experimental results show that the simulation result is valid, which has practical merit of operation and technical optimization of dryer.