Applied Mechanics and Materials Vol. 459

Abstract: Two arms are attached on the live-working robot for cooperating jobs and some task requiring larger stiffness such as pushing and butting when replacing cross arm or insulator. The different kinematic structure of this two arms brings many difficulties to get the dynamic model of the total system. This paper proposes a force control method to solve this problem. Two arms are considered as one arm firstly, then the general stiffness matrix is obtained. And based on the compliant relationship between the dual arms and the environment, the force control method for the exact force control is presented. The scheme is experimentally tested on the live-working robot, and the effectiveness and rapidity is validated .

Abstract: With the remarkable development of parallel computers, computing scale is becoming larger. Recently, it is an important trend to use iterative approaches to solve differential equations. Among them, the waveform relaxation method as a dynamic iterative method has good parallelism. This method will be compared with direct integration and shooting method using A Mathematical Programming Language (AMPL) in nonlinear circuit to verify the efficiency of waveform relaxation approach.

Abstract: Power system dynamic problem is the study which dealing with synchronism among interconnected machines. In any scenario all interconnected synchronous machines should remain in synchronism if the system is stable; i.e., they should all remain operating in parallel and at the same speed. Wind penetration level is affecting power system stability performance. This may result in oscillatory, but if the system is stable, these oscillations will be damped towards to stable operating condition. If the system is unstable, these oscillations will not be damped out and causes damage to synchronous generator. This dynamic performance can be improved by StatCom technology.

Abstract: Using the derivative of the Boolean function and the e-derivative defined by ourselves as main research tools, we study the relationship among e-derivative, algebraic immunity and resilience of balanced H Boolean functions.We get some theorems which connect algebraic immunity, annihilators, resilience, derivative and e-derivative of balanced H Boolean functions together. Besides, we also get the judgment of algebraic immunity and resilience for three classes of balanced Boolean functions by the e-derivative.

Abstract: In this paper, the break-away and break-in (BABI) condition used in root-locus approach for two-parameter linear control systemsis derived. The condition for one-parameter control system can also be obtained from those results, which agrees with the well-known results by using sensitivity function (e.g., Kuo, 2009). Based on those conditions, an algorithm is proposed to construct the PD control gains of linear control systems for meeting designed specifications of timing response. Compared with the conventional design by using root-contours, the proposed approach can give a guideline for choosing control gains instead of those obtained by trial-and-error from the root-contours scheme. An example of the 3rd-order linear systemwith PD control is also given to demonstrate the feasibility of the proposed design.

Abstract: The short message service (SMS) has been put into the application well in many professional areas, and how to apply it in the instruction management is a subject allowing the personnel working at educational technology area to solve. This paper analyzes the constitution of short messages and describes the design of the short message service platform on the campus network based on the B/S structure, and presents the method of how to carry out the short message service platform based on the WEB in which we can integrate the information releasing and order function to play the information.

Abstract: This paper presents new results to compute the time-delay margin of the hot-dip galvanizing control system. Compared to previous works on this issue, this paper considers a mathematical model of the plant with two inputs and one output. The inputs are used to regulate the output, which represents the Zinc mass coating of steel strip. To achieve this objective, a multivariable PI controller is used, this controller is tuned applying the well known Ziegler and Nichols method, and then the maximum time-delay is computed in order to guarantee the stability property of the close loop control system. The work bases its results on a transformation of the time-delay operator and it is performed in order to get a two variable polynomial; after this, to obtain the robust stability property, a result based on the Hurwitz matrix is applied.

Abstract: This paper presents the scheme of a physiotherapy service robot including the mechanical architecture, control system, visual position system, etc. The robot can treat degenerative disease and chronic disease of middle-aged and aged people by Chinese massage skill, the main body of which includes a massage adjustable bed, two 4-DOF robot arms and two massage hands that can accomplish various massage manipulations. Two arms cooperate to improve the massage efficiency, and provide sufficient strength and enough reachable workspace for massage. The manipulators are controlled by a TRIO multi-axes motion controller and a embedded computer module. Physiological signal and massage pressure is detecting in real time in massage process to ensure a scientific and safe therapy. Vision System sends the recognized acupoint position to the master system to track the patients body, and the acupoint being massaged is displayed in real time by the 3D virtual display model. The robot can execute ten massage manipulations, which make traditional Chinese massage can have a robot instead. The effectiveness for degenerative lumbago in middle-aged and aged is demonstrated by laboratory examination and clinical trial.

Abstract: Electroencephalogram (EEG) is generally used in Brain-Computer Interface (BCI) applications to measure the brain signals. However, the multichannel EEG signals characterized by unrelated and redundant features will deteriorate the classification accuracy. This paper presents a method based on common spatial pattern (CSP) for feature extraction and support vector machine with genetic algorithm (SVM-GA) as a classifier, the GA is used to optimize the kernel parameters setting. The proposed algorithm is performed on data set Iva of BCI Competition III. Results show that the proposed method outperforms the conventional linear discriminant analysis (LDA) in average classification performance.

Abstract: In this paper, the traditional NSGA model in solving multi-objective optimization problem exists the computational complexity, lack of elitism and the need to set shared radius etc. defects. we use the advantage of the artificial immune system, such as good generalization, self-organization and so on, propose a improved multi-objective adaptive artificial immune genetic algorithm that by the use of fast non-dominated sorting and crowding distance, reduces the algorithm complexity and improves its stability and versatility; utilizes the immune memory cells to optimize the population quality, accelerate the antibody reaction speed and raise the optimize efficiency; updates the populations by the non-inferior rank and crowding distance to improve the algorithm function of the search. This paper elaborates the algorithm steps in detail and verifies this algorithm. Through the three different dimensions of test functions, the simulation results show that this algorithm is effective and feasible.