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Nonlinear vibration damage of pipes conveying fluid is a major problem in today’s production and life. Enormous economic loses and safety hazards were caused by nonlinear vibration. Pipes conveying fluid with various branches are very common in actual engineering. Their mechanical properties and vibration mechanism is quite different from that of pipes conveying fluid without branches. This paper showed the nonlinear vibration mechanism of pipes conveying fluid with vertical branches and nonlinear vibration damage factors. Nonlinear vibration theory was used to check the pipeline and some reference data for the rational selection of working parameters were provided.

The paper proposes and develops a distributed control system of ceramic material shuttle kiln control of MVC pattern based on the current ceramic material shuttle kiln control in which exist plenty of disadvantages such as wasting energy sources, low efficiency, bad precision and long periods, etc. Firstly, it introduces the basic theory and the system structure graph of the MVC pattern, and discusses in detail the design layer frame and structure characteristic of control system based on MVC pattern. Finally, under the environment of the Delphi, this paper illuminates the material realization of the MVC form of the total control system with adopting the multi-thread shared same buffer method. Practice development shows that the MVC pattern can separate easily the interface of operator and computer, operation logic and data disposal, which makes the total control system have the fluent trait, the spread trait and the easy maintenance trait.

Torque measurement of transmission shaft has problems such as signal transmission, limited installation space and signal disturbance. In this paper proposes an embedded capacitive grid torque sensor. Through a special installation the output of capacitive grid sensor is proportional to twist angle, then torque can be calculated. The two electrodes of capacitive grid sensor can be embedded into the bearing and shaft respectively that reduces installation space, to improve the testability of transmission shaft. Experiments show that capacitive grid sensor performs high reliability and is able to be used in the case of strict environmental requirements in long time.

A real-time application is proposed for Android smart phone. To achieve the best tradeoff between the complexity and the processing efficiency, Java Native Interface (JNI) is used rather than pure Java. The performance of the application is tested on an Android smart phone by dealing with various pedestrian videos. And the experimental results show that the application successfully detects and tracks certain moving object.

In this paper, using the discrete element method (PFC2D)particle flow procedure to establish a model of cylindrical silo, in the warehouse filled with particles within the reach of static equilibrium state, then the record of its wall static lateral pressure measurement value, while monitoring the measured dynamic wall pressure during the silo discharging. It was shown that the static pressure as well as the dynamic pressure simulated with the numerical model is in good agreement with the experimental results. So the discrete element method can give a new way to study dynamic question of silos.

In this paper, the anti-calculated method for the static pressure associated with the silo structure is developed and the strain sensitivity is derived based on the formulations of the finite element method. In the proposed approach, the Taylor expansion technique at the initial guess strain is used to evaluate the hoop strain at adjacent points and the least square method are employed to match the numerical results and the known test results. Finally, the developed algorithm is verified by solving the silo with internal wall.

The objective of this study is to develop a finite element analysis model that simulates the temperature profile in concrete-filled steel tubular structures during welding procedure in which several metal plates are fixed on the outer surface of steel tube to increase the strength and stiffness of it. In the present model, the thermal property such as thermal conductivity of the steel phase is assumed to be functions of temperature variable. Spatial and temporal distributions of temperature are illustrated under extreme weld heating conditions to investigate the behaviors of the structure at every time step. Simulation results indicate that the maximum value of temperature on the interface of steel and concrete caused by the weld heat source doesn’t damage the mechanical properties of concrete and steel.

A new numerical integration method for dynamic finite element analysis is proposed in the paper. In the proposed algorithm, the acceleration change in a particular time step is first assumed to be curved variation, and then the displacement vector, velocity vector and acceleration vector at the current instance can be expressed in terms of the results at last time instance. Because of the curvilinear property of the acceleration change in a particular time interval, the complicated dynamical responding such as high-oscillatory modes can be captured with the present method. The efficiency and accuracy of the proposed algorithm are validated by two numerical examples and numerical results show that the present formulation has better accuracy than the Wilson’s method and the Newmark’s method used in the conventional finite element method.

In this paper, novel filled materials EPS-blocks of cast-in-situ slabs are presented. And EPS-blocks with light weight which are inexpensive are validated to be sufficient strong as filled materials to bring an innovation for the development of cast-in-situ slabs. Based on modal analysis, it is found that the decreased weight has a greater influence to the mode of the slab than the weakened stiffness. According to harmonic response analysis, tensile stress distributions of the slab with EPS-blocks are depicted in figures and explained. Typically, orifice stress distributions are expounded and stress variations of nodes in different places are illustrated. From these studies, it is concluded that the steady state dynamic performance of the slab with EPS-blocks is good.

A new cast-in-situ slab which is filled with novel filled material (EPS-block) consisting of disused expanded polystyrene plastic granule, cement and building cementing powder is invented. EPS-block with perfect centrosymmetric torus shape is very suitable for filling into two-way slabs. It breaks a new path to use disused expanded polystyrene foam, and reduces environment pollution greatly. Through the practical study of the slab with EPS-block, the appropriate construction method is found out, and the dependable construction technique is afforded for further development of the slab with EPS-block.