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The ultrasonic vibration assisted compression process is analyzed from the viewpoint of the impact dynamics. The typical metal forming patterns are studied based on the theory of wave propagation in solid. The effects of the geometry scale, friction, material parameters, ultrasonic amplitude and ultrasonic frequency on the forming process are analyzed. A combined parameter is proposed to evaluate the impact of the ultrasonic vibration on the specimen. The typical metal forming parttern are demonstrated by the experiment result of the literature.

Aiming at the deficiencies of traditional PID control algorithm, the application of Fuzzy PID control algorithm is proposed in variable frequency speed regulation system of glass edge grinding machine. The design of fuzzy PID controller is presented in the paper. The paper not only introduces the system principle and models for inverter and AC asynchronous motor but also tells the principle of Fuzzy PID Controller and its design method. A simulation model including traditional PID Controller and Fuzzy PID Controller is established in MATLAB/Simulink. Through the analysis of the difference between the two controlling outputs, the better performance of Fuzzy PID Controller in response speed, accuracy and stability is proved effectively. The result can be used as important criterion to the practical application of Fuzzy PID control algorithm.

A multiple variable model is developed for a multiple-effect low temperature desalination system. Multiple-effect water desalination has been used in industry for decades due to its high efficiency and high quality of fresh water production. Here, its dynamical process is modeled based on the mass and heat conservation laws and then expressed in terms of a state space equation, enabling people to carry out analysis and design controllers.

An extreme seeking (ES) method is given for the optimal design of the thermal energy storage (TES) tank in a trough solar collector system. The energy storage tank in such a solar energy collector performs a filter which regulates the heat transfer in some applications. It is desirable that the volume of the TES tank is optimized in terms of the best performance of heat regulation. The main idea is to construct a simulation scheme that emulates repeatedly the dynamical process and varies the key parameter of the tank at all iterations. The governing algorithm is a convex optimization. A case study that incorporates the above method is examined in the city of a province in China. It is shown in the numerical results that the volume of the TES tank is key variable that influences the performance of heat transfer; the proposed ES method is effective to seek the optimal volume.

We design a controlled thermal solar desalination system that can operate at some desirable conditions automatically. The scarcity of fresh water in some regions pushes forward to the industry of water desalination. However, the existing water desalination technologies are energy-consuming and the cost is high. Here, a water desalination system is designed in such a way that the solar thermal energy is used to take place of the fossil fuel energy and the operation of the whole system becomes automatic. As a result, the proposed system is environmental friendly endowed with the green energy and the cost is reduced due to the elimination of the costly fossil fuel.

The three-dimensional CAPP prototype is studied based on Solid Edge platform using the technology of secondary development of VB. The system is able to complete part the selection of machining feature of the part, edit of process information and selection of process. The system finally output process card semi-automatic or automatic, through the module of process edit and the module of process card output module having the support of the process resource management module.

In metal forming process analysis, the accuracy loss is inevitable for complex boundary shape, un-uniformly distributed points and high velocity gradient distribution in analysis domain. In order to improve simulation accuracy, an h-adaptive procedure for the background required rigid (visco) plastic meshless Galerkin method is developed. A mixed posteriori error indicator is presented, which consists of a cell energy rate integration error estimator and a cell energy rate approximation error estimator to indicate the integration error and the approximation error, respectively. The corresponding local refinement strategies are developed, and the adaptive refining procedure is given. The adaptive procedure is applied only once in each time step simulation for the consideration of computational efficiency. A bulk forming process with severe metal deformation is analyzed. In comparison with the results obtained by using software Deform-2D, the effectiveness of the method developed in this paper is demonstrated.

According to the phenomenon that most website display products through the form of two-dimensional and can not resolve interactive issue between users and virtual scene. This paper design a virtual roaming system which uses 3ds max to perform modeling for all the scenes in the store and make dynamic interactive design for model on Virtools platform, and study two types of collision detection. In this roaming system, users can walk freely in the store and operate interested in commodities independently like entering the real world.

The three parameters of P-wave velocity, S-wave velocity, and density have remarkable differences in conventional prestack inversion accuracy, so study of the consistency inversion of the “three parameters” is very important. In this paper, we present a new inversion algorithm and approach based on the in-depth analysis of the causes in their accuracy differences. With this new method, the inversion accuracy of the three parameters is improved synchronously by reasonable approximations and mutual constraint among the parameters. Theoretical model calculations and actual data applications with this method indicate that the three elastic parameters all have high inversion accuracy and maintain consistency, which also coincides with the theoretical model and actual data. This method has good application prospects.

This paper focuses on multi-disciplinary resource configuration optimization problem of collaborative manufacturing in an open environment. First a semantic-based manufacturing resources retrieval and deployment framework is presented, then the four layers of the proposed framework, i.e. resource modeling, resource retrieval and annotation, resource discovery, and optimal resource deployment are discussed in detail.

A total of 205 dialysis patients with renal insufficiency were selected as an experiment group, and 360 healthy people were selected as a control group. The specific IgG antibodies of Toxoplasma gondii of the objects in the 2 groups were detected by ELISA. The positive rates of the experiment and control groups were 27. 3% and 3. 6% ,respectively, with a significant difference between them (P0.05). Among the dialysis patients with renal insufficiency, the positive rates of the patients with or without a history of blood transfusion were 31.2% and 19.2% , respectively, and there was a significant difference between them (P0.05). In conclusion, the infection rate of T. gondii in dialysis patients with renal insufficiency is higher than that of common people, and dialysis and/or blood transfusion may be potential risk(s) for Toxoplasma gondii infection.