Abstract: This paper proposed a novel micro wave energy converter which can convert irregular wave energy into rotating mechanical energy, then into electrical energy. The device consists of an energy absorption part and an energy conversion part. In details, the blades are installed on the absorber circumferentially and averagely, which are capable of converting the vertical motion of the surface body to continuous rotation of the absorber and leading to a great increase in efficiency. A physical prototype was built to test the performance of the novel generator and optimize the design parameters. In the experiment part, a linear motion electric cylinder was used as the drive power to provide the heaving motion for the device. And the experiment platform was built for modeling a marine environment. Also, a data acquisition program was edited in Labview. Thus, the experiment analyzed the influence of amplitude, frequency, blade angle and resistance value to the output power, and then obtained the optimum parameters combination which can maximize the value of the output power. The result will provide reference for the device’s further application.
Abstract: By using different annealing processes to anneal the pressure-measuring cylindrical copper cylinder, playing some static experiments on different copper cylinders, the difference of pressure measuring performance of copper cylinder was analyzed. Results show that, by using current annealing processes all can achieve the purpose of full softening the material of the copper cylinder and the deformation of copper is not significantly affected by the different temperatures. Some copper cylinders which use short holding time have poor linear sensitivity, but their measurement deviation is better than those which use longer holding time. So, in the actual production of copper, we should use shorter annealing time to improve their measuring accuracy.
Abstract: NVH control in construction machinery is multi-disciplinary, comprehensive and complex. In order to achieve noise and vibration control, it is necessary to identify the main noise sources, vibration sources and the corresponding characteristics. To establish a relationship between the machine vibration with the noise sources of an excavator cab, the ICA (independent component analysis) method is employed to separate the multi-channel noise signals into statistically independent components, then utilize time-frequency analysis and correlation analysis to determine the distinct independent noise sources. By introducing energy calculation factor and the mixing matrix A, the contribution corresponding to each noise source can be obtained, which can be utilized to determine the main noise sources. Then by introducing simulation, the correction of the contribution can be verified. By analysis and simulation validation, the effectiveness of our proposed method is demonstrated. Finally, the main noise source is found. Our proposed method can offer an effective guidance to the practical engineering.
Abstract: In dynamic cooperative games, a player may use ‘irrational’ acts to extort additional gains if conditions allow. For the differential game problem occurred in the infinite interval, we propose a new asynchronous irrational behavior proof (AIBP) condition. This condition requires that the later the irrational behaviors appear, i.e., the more time the player participates in cooperation, the higher payoff the player will get. Considering the differential game about the problem of emission reduction among countries, we show that the AIBP condition can make the cooperation last much longer.
Abstract: The working environment of the inspection robot is a high altitude flexible cable environment. The robot navigating process must be stable and reliable. The robot mechanism grips the line though locomotion mechanism when navigating obstacles. The locomotion mechanism needs to have a strong clamping capacity and stability. According to the environmental characteristics of transmission lines, a novel locomotion mechanism of inspection robot is presented. The locomotion mechanism adopting differential mechanism can grip different diameter lines. The Tri-Step reducer design to ensure that the various model lines of rapid firmly clamped. The locomotion mechanism is introduced, and the gripper force is analyzed. The experiment results demonstrate that the mechanism has such characteristics as strong grip ability, good motion stability, and different diameter lines gripping capability.
Abstract: The technology of high voltage electrostatic field has been used for food processing in recent years, especially for thawing and freezing of food. However, the application of this technology on food cooking is still in the initial development stage. Although there are a little applications of food cooking using high voltage electrostatic field in some restaurants in Taiwan area, the corresponding study is very scarcely. This study describes mechanism, principles and devices of electrostatic cooking of food, as well as results of some electrostatic cooking experiments. Obviously, the high voltage electrostatic technology can be beneficial for food cooking, and the effects of sanitery and health of electrostatic cooked food are important for human body.
Abstract: This paper describes the use of an unbalanced control strategy to solve the faults occur in AC grid side of High voltage direct current based on Voltage Source Converter (VSC-HVDC) system. This method divides the voltage and current parameters into negative-sequence and positive-sequence. It can be obtained that the negative-sequence appears as double-frequency component in the positive-sequence synchronous reference frame; while, it appears as dc component in the negative-sequence synchronous reference frame. To mitigate the unfavourable impact of the unbalance fault, such as the DC link ripples, the dual vector control algorithm in dq synchrounous reference frame is designed. Simulation results demonstrate the validity and the effectiveness of the proposed control scheme.
Abstract: This paper presents a review of some of the applications for artificial muscle and several material of artificial muscle. We focus attention on the polymer material artificial muscle, which responds to electrical stimulation with a significant change in shape or size. Through our research on a variety of materials and the analysis of the mechanical properties of muscle movement, finally we designed the artificial muscle device the imitation of muscles stretching device. This article describes the structure and performance of the device.
Abstract: In the field of machining industries it is always required to improve the accuracy of precise products, die and molds. The feed drive system for the machine tools consists of an AC servo motor, an amplifier and rolling elements etc. It is well known that the nonlinear behaviors of the rolling elements influence the motion accuracy of the feed drive system. However, in spite of the analysis of static behaviors have been done, the dynamic behaviors are not so examined. Our special interest is how to control the nonlinear behaviors of the rolling elements and to operate the feed drive system with high accuracy. In order to model the nonlinear behaviors of the feed drive system, we measure the transient response when the step inputs of microscopic displacement are input to the AC servo motor and the detail analysis will be done. Experimental results show that the step responses become slow as the input displacement becomes microscopic. It means that with the ball bearing built into the AC servo motor used to feed driving system have the nonlinear behavior in microscopic displacement range.
Abstract: A multiphase numerical study has been carried out to understand the effects of wind turbine blade profile (airfoil) symmetry on resultant ice accretion. Two symmetric (NACA 0006 & 0012) and two non-symmetric airfoils (NACA 23012 & N-22) were used for this preliminary study. Based upon the airflow field calculations and super cooled water droplets collision efficiency, the rate and shape of accreted ice was simulated for rime ice conditions. Analysis showed higher air velocity along top surface of the non-symmetric airfoils as compared to symmetrical airfoils that also effects the droplet behavior and resultant ice growth. Results show that change in blade profile symmetry effects the resultant ice accretion. For symmetric airfoils, more streamlines ice shapes were observed along leading edge as compared to non- symmetric airfoils.