Key Engineering Materials Vols. 439-440

Abstract: 3DOF nonlinear braking dynamic model considering tire-road adhesion characteristics was established, and non-dimensional equations were gained from the above mathematic models by using braking torque coefficient, front and rear axle equivalent inertia coefficients and braking force distribution coefficient. Based on the numerical calculation in Matlab-Simulink software, the effect of key factors, (including vehicle mass and vehicle gravity center position variation, frontal and rear braking force distribution coefficient, and frontal and rear axle inertial variation caused by driven mode) on vehicle braking performance, such as braking distance and wheel lockup status, was investigated and summarized. Several 3D visualizations of the simulation results show that variation of vehicle center of gravity, vehicle mass, braking moment distribution, wheel equivalent inertia due to driveline, can cause quite complex effect. It can be assumed that the gained results in this study can help to improve vehicle braking performance and enhance braking stability.

Abstract: In order to improve ammonia removal capability from wastewater, zeolite was modified with heat and biofilm in this paper. The results showed that the adsorption capacity of heat modified zeolite could be reach mean value of 120.18meq/100g, which was 1.55 times than virgin zeolite. The results of bench scale experiments also showed that the data in the experiments were in line with Langmuir isotherms for ammonium ion absorbed onto heat modified zeolite. Moreover the biofilm which attached on the surface of heat modified zeolite only modified the surface feature of modified zeolite, while ion-exchange and diffusion procedure were not affected.

Abstract: Focusing on a type of uncertain continual time-lag systems, study on the designing problems of law in reliable guaranteed cost feedback control when actuators are in fault condition of continuous-gain. Apply of the processing method of linear matrix inequality, derived out the condition that reliable guaranteed cost exist, and give out the parameterized representation of all the reliable guaranteed cost control law. In this foundation, we can further obtained the designing method of optimal reliable guaranteed cost control law.

Abstract: A multifunctional inverter welding machine with the functions of DC gas tungsten arc welding, argon tungsten pulsed arc welding, manual arc welding and air plasma arc welding gather in integral whole is introduced in this work. In whose development, the theory of half-bridge series resonant inverter is used as the basis, while the fast SCR as the inverter. When in the situation of welding, full-wave rectification is used, with a working voltage of 36V; while in the situation of cutting, bridge rectifier is used, with a working voltage of 100V~125V. According to a large number of experiments and tests in the development process, the correctness of the mathematical modal of the fast SCR inverter is verified, and a new method of inverter circuit parameter design is obtained. By which, the theoretical basis is provided for the development of inverter welding machine.

Abstract: For sophisticated background, a human body tracking algorithm using particle filter based on a 3D articulated body model is introduced. First, a high-fidelity biomechanical upper body model, which is accurate for representing varies complicated human poses and simple to be developed, has been built. Then sequences of images are obtained by using a stereo camera. After calibration, verification and background subtraction, depth map, foreground silhouette, arms skeleton are chosen to construct the likelihood function. The state vectors describing the human pose are computed by fitting the articulated body model to observed person using particle filter. In order to reduce the computational complexity and the number of particles, constraints are employed to restrict the state parameters. Experimental results show that the proposed algorithm can track human upper body with different poses, different person under different illumination conditions fast and accurately.

Abstract: Recently, many works have employed deterministic strategies in dealt with flow scheduling problem in Air traffic flow management (ATFM). In practice, however, they are proved unreasonable for omitting airline’s preference in ATFM. In this paper, we develop a novel air traffic flow control model based on game theory to solve this problem in air traffic network. In the flow model, a resource (link/time pair in air traffic network) allocation strategy that uses sequential game method to predict traffic allocation is proposed in resource sharing environment. The problem of multiple airlines competes for an optimal route is formulated as a multi-player dynamic game. Through finding the Nash equilibrium solution of the multi-player dynamic game, the optimal flow scheduling is also formed at the same time. The flow model also incorporates many key characteristics of ATFM, such as competitive airlines, allowing multiply flow control strategies and so on. Numerical simulation results show the feasibility of solving the air traffic flow control problem using game theory on the air traffic network.

Abstract: One course radius measurement method for vertical petroleum tank volume metrology based on 3D laser scan principle was researched. Method of distance measurement by laser phase-shift technology and angular measurement by optical grating was applied to acquire coordinates of points in each course under the control of servo system. The permitted error of measured point location is 2mm. Fitting algorithms base on direct iterative method (DIM) and least square method (LSM) were used to process measured data and deduce equivalent radius of each course. In comparison experiment, one 1000m3 vertical tank was used as test object. Compared to strapping method (international mandatory standard), the maximal deviation radius value of method discussed is 2.8mm. The maximal difference of radius value calculated by DIM and LSM is 0.1mm. The experimental results verified the method discussed in this paper.

Abstract: In current, constant speed of asynchronous generator system has been used wind farm in China areas. But because of that abilities of reactive power control helpless, reactive power have been provided by grid. In view of the above situation, the feasible measures are adopted in the wind dynamic reactive power compensation devices. The asynchronous machine transient process used reactive power to keeping voltage of machine has been provided. This article introduced the Game Theory in economics to the area of reactive power compensation. This new method of the share of reactive power in wind farm, will improve wind farm reactive power compensation too vague to efficient in the moment. In the meantime, the share of reactive power algorithm analysis process have bee bullied in this paper. For the research in the future, it proposed supplementary opinions.

Abstract: According to the specific property of traction supply system, a novel hybrid active power filter (HAPF) is designed in this paper. The new HAPF topology is that, after the impedance of fundamental wave is in parallel with the active power filter (APF), it is series connected passive filter. The kinds of structure can reduce the VA rating of the APF greatly. The small rating active power filter is used to improve filtering characteristics of the passive filter and suppress possible resonance between the traction supply system impedance and the passive filter. Through MATLAB simulation, it shows that the control strategy of power quality is apparently effective, and it plays an important role in enhancing the reliability of transformer station and the operating security of electric railway.

Abstract: To make the environmental performance measuring system a useful inspective and supervisory tool during the life cycle of a Green Manufacturing (GM) program, a measure system is presented. It includes three primary indexes corresponding to the GM program life cycle, which are fundamental construction level, application level and continuous improving level. And 19 secondary measures are subdivided, too. After that, the values of the measures are determined involving qualitative and quantitative index. And then Back Propagation Neural Network (BPNN) is applied to evaluate the environmental performance of GM programs in enterprise, in which 10 samples are used to train the measuring model with Matlab 7.0, and the data are selected from the Internet and digital library. The environmental performance evaluation of a machine tool company in Chongqing shows the effectiveness and validity of the model, and this method can be applied in industrial enterprises while implementing GM.