Advanced Materials Research Vols. 211-212

Abstract: With the rapid growth of e-commerce, various types of complex applications appear in web environments. web-based system testing is different from traditional software testing. The unpredictability of Internet and web systems makes it difficult to test web-based system. This paper presents an engine for Fuzzing test data towards web control vulnerabilities, and introduces "heuristic rules" and "tagged words" to generate the test data. This method can increase the intelligence of security testing and build the foundation of web vulnerability detection model.

Abstract: In order to reduce the working power of tillage implement, made a combination of the down-cut rotary tillage and the up-cut rotary tillage applied on small agricultural machine is proposed. SPH method is applied to the three-dimensional numerical simulation for rotary soil process of rotating, and thus draws the force characteristics of rotary cutting tools under the different parameters. Combining with the simulation data of the up-cut rotary tillage, the work of tool matching is done. So it can make the force of the up-cut rotary blade and the down-cut rotary blade offset respectively. Accordingly, the small agricultural machinery can reduce energy consumption and improve efficiency. Based on these methods, we develop the small farming machinery which is fit for farming in compacted soil. The data and analysis program based on the study are of great significance for the small farming machine.

Abstract: As one of the most common parts of various rolling mechanical equipments, rolling element bearing is vulnerable. Therefore, great attentions have been attributed to the theories, failure diagnosis methods and their applications for rolling bearings. Vibration analysis is also a very important means for bearing fault diagnosis. This paper aims at the research on the methods of signal processing and pattern recognition. An experimental platform was set up for the failure diagnosis of rolling bearings, on which we have done a lot of experiments. Then the vibration signals of normal rolling bearings, rolling bearings with failure on the outer and inner race were collected. Time-delayed correlation demodulation was applied and the features of vibration signal were effectively extracted. Fuzzy C-means clustering system was established to carry out the recognition of the fault of bearings. Experimental results have proved the developed fault diagnostic architecture is reliable and effective.

Abstract: The swing-up control strategy via BVP arithmetic is presented for rotational inverted pendulum. The swing-up control programming from hanging to the upright position can be transformed into the two-point boundary value problem (BVP) of nonlinear systems. According to the boundary conditions of the swing-up process, the control torque function of Fourier series form with free parameters is constructed. The BVP is solved with the bvp4c function in Matlab toolbox, and the control torque sequence is obtained. The swing-up process is open-loop feedforward control essentially. In order to inhibition parameters perturbation, the closed-loop stabilizing control is designed around the upright position for the inverted double pendulum with unstable zero-dynamics. The simulation of swing-up, stabilizing and switching process illustrates the effectivity of the control strategy.

Abstract: The piezoelectric material is subject to hysteresis and creep resulting in a nonlinear relationship between the applied voltage and the output mechanical displacement. An approach for compensation of both the hysteresis and creep characteristics of a piezoelectric stack actuator is proposed by utilizing a switched capacitor charge pump. The new charge pump transfers the same amount of charges to the piezoelectric actuator quantitatively, and the actuator will be excited to change its length with constant step. Compared with voltage driving mode, experiments show that both creep and hysteresis of the piezoelectric stack driven by the charge pump are effectively reduced. A hysteresis reduction of 86.10% at 0.01Hz and 94.36% at 5Hz is achieved. At the maximum driving voltage, a creep reduction of 77% is obtained.

Abstract: Track irregularity is the most important excitation source of wheel-rail system. The vibration characteristics of vehicle components and track components are analyzed in this paper under the condition of track irregularity by establishing the vehicle - track vertical coupling model. And the establishment of vibration differential equation and numerical simulation method for solving vibration response are described in detail. Finally, the results are given by MATLAB. The method is of great significance for evaluating the dynamic track irregularity and vehicle’s vibration at different running speeds.

Abstract: A pipeline robot is brought forward using the energy of fluid medium transmitting within the pipeline to perform the driving and timing. The robot is soaking in the pipeline full of flowing fluid medium and getting the driving force from the press and velocity energy of medium itself to push forward it. It is discovered during the research that robot need to overcome the gravity and influence of the friction resistance with the pipe wall while driving alone, so for the different mediums and applying situation the robot required to velocity adjustment automatically. According to the condition of the hydrodynamics within the pipe and designing in reason for the size and configuration of the robot, a velocity controlling device is worked out and realized its velocity adjustable.

Abstract: The impeller mounted onto the compressor shaft assembly via interference fit is one of the key components of a centrifugal compressor stage. A suitable fit tolerance needs to be considered in the structural design. A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference-fit loading was considered in the numerical analysis. The FE parametric quadratic programming (PQP) method which was developed based on the parametric variational principle (PVP) was used for the analysis of stress distribution of 3D elastoplastic frictional contact of impeller-shaft sleeve-shaft. The solution of elastoplastic frictional contact problems belongs to the unspecified boundary problems where the interaction between two kinds of nonlinearities should occur. The effect of fit tolerance, rotational speed and the contact stress distribution on the contact stress was discussed in detail in the numerical computation. The study play a referenced role in deciding the proper fit tolerance and improving design and manufacturing technology of compressor impellers.

Abstract: IC- (Integrated circuits) sorting machine is a kind of special equipment used for testing, classifying and grading IC chips, which is of significances in IC industry. Traditionally, IC- sorting machine is controlled by industry personal computer (IPC), which bears disadvantages such as large size and high cost. By contrast, the control system for IC-sorting machines presented in this paper is based on micro control unit (MCU), which is of relatively high reliability as well as high stability but low cost. First, we gave an outline of the configuration and operation principle of the sorting machine. Second, the input and output (I/O) signals that should be controlled were classified. Last but not least, the control strategy was presented both from the hardware side and the software side. In terms of the hardware design, touch screen was adopted as the human interface device (HID) for the sake of convenience, and isolated power module as well as optical isolated module were applied to improve the anti- electro magnetic interference (EMI) performance; In terms of software design, mechanisms such as multi-task by-turn and timer interrupt delay were adopted to improve the operation efficiency.

Abstract: This paper presents a multiscale method to estimate the elastic property of the 13_3 microtubule. A microtubule is viewed as being formed by rolling up its planar encounter into the tubular shape, and the transformation is written into a set of equations with three geometrical parameters. The representative cell is chosen as an unit of two pairs of tubulin momoners. With the appropriate longitudinal and lateral interactive potentials, the strain energy density is calculated by deviding the cell’s energy by its spacial volume. The elastic property of microtubule is determined by minimizing the strain energy density, and the elastic constants are calculated in the thereotical scheme of orthotropic elasticity due to the geometrical meanings of the induced parameters. The advantage of the proposed method and its future application are discussed.