Applied Mechanics and Materials Vols. 513-517

Abstract: Forest fire spreading is a complex burning phenomenon, and it is difficult to build a general spreading model for the fires occurred in different area over the world, even in the same country. Accordingly, predicting the burned area of forest fires is also a challenging task. In this work, five attributes (i.e. forest fuel moisture content, forest fuel inflammability, forest fuel load ,slope and burning time) are selected as input to predict burned area of forest fires occurred in the area of Guangzhou City in China. Next, using Data Mining (DM) technique, an SVM (Support Vector Machine) model was built and applied to deal with this type of a regression task, predicting burned area. Results showed that the selection of input attributes was reasonable, and the proposed SVM model was suitable for prediction of burned area, with higher precision, better generalization. This work provided a new way to deal with predictions for burned area of forest fires.

Abstract: Option is the typical representative of financial derivatives, and this paper is focused on the valuation problem of Option. Based on the Black-Scholes Pricing model which had far-reaching influence on the pricing of financial derivatives, researched its theoretical basis and derivation process, and then get the numerical solution via finite difference method and image simulation. And it also includes the part of empirical studies. In research, ZTR and HQ is chosen and analyzed, in order to get the pricing of European put option.

Abstract: Controlling of the pollution plays an important role in environmental monitoring. This paper proposed a prediction model for the evolution of pollution in a certain region. With the statistic data of the pollution in this region, several parameters can be determined. With solving the related partial differential equation, the evolution of the pollution in next days can be predicted. Then some efficient measures can be adopted for controlling. The efficiency and the accuracy of the proposed model are shown in presented numerical examples.

Abstract: Lower Extremity of Power Assist Robot could add the strength and endurance of robotics to a human's innate adaptability to help the wearer transport heavy loads over rough and unpredictable terrain. Dynamics Analysis and Control Strategy Simulation are the important aspects for the researching of the robot. The dynamics equation of Lower Extremity of Power Assist Robot is built by the Lagrange equation. The relationship between the active joint torque of the robot and plantar pressure is established, which support the theoretical foundation for the dynamic control to achieve the desired effect. Base on the analysis of working environment and the mechanical environment of the robot, the force-location control theory is used to control robot, which is simulated based on Simulink blocks of MATLAB to get a better tracking performance.

Abstract: as an important research field of automatic control problems, PID parameter optimization's control effect depends on the proportional, integral and derivative values. Using trial and error testing to manually realize optimization PID parameters, the traditional ways are often time-consuming and difficult to meet the requirements of real-time control. In order to solve the problems and improve system performance, the paper proposes a PID parameter optimization strategy based on genetic algorithm. The paper establishes the PID controller parameter model through genetic algorithm, uses the PID parameters as individuals in genetic algorithm during the control process, and takes the integral function of absolute error control time as the optimization object to dynamically adjust the three PID control parameters, thus realize online optimization for PID control parameters. Simulation results show that the introduction of genetic algorithms for PID control system improves the dynamic performance, enhance system stability and operation speed, and get better control effect.

Abstract: With the development of active noise control technology, ANC system has been gradually introduced into practical application. And some researches and experiments notice that ANC system may encounter with nonlinearity problems under certain conditions in practical applications. The paper analyses and summarizes possible factors that may lead to nonlinearity problems, based on the operation principle and structure features of ANC system, and classifies the main methodologies of dealing with nonlinearity problems considering the main technologies and researches nowadays of system nonlinearity with the same analyzing structure of nonlinearity factors mentioned in the paper. The paper also elaborates the strength and weakness of different methodologies and the most appropriate application condition for each methodology, and it provides theoretical basis for nonlinear active noise control system.

Abstract: The inspection methods and ways of automatic control system fault positions directly link to the feasibility of products. The paper bases on basis principles of image recognition, studies on the module design of automatic control system images and fault image recognition algorithm, puts forward depressed windowing grey level linear partitioning characteristic extraction algorithm and control system fault characteristic recognition algorithm and check its feasibility.

Abstract: This paper mainly concentrates in building a solution model for coordinating the relationship of transport and customers' satisfaction in returns. The simpler the transport steps of returns are, the higher the satisfaction level of customers will be. Otherwise, the satisfaction will reduce and cause bad effects on the corporate reputation. The paper proposed an optimization method for logistics and transport steps with constraints in returns which constrains the return steps, reduces conflicts and reduces cost. It provides theoretical basis and practical guidance to reasonably improve the logistics and transport steps in returns, and furthermore helps to improve the customers' satisfaction and the corporate reputation.

Abstract: CCD technology is used in production process of cultural products to detect flatness, which reduces the error formation probability. This paper proposes an image detection model for cultural production flatness measurement based on computer vision feature point matching algorithm. The method uses the pixel frequency sorting method to divide pixel level of collected images, so as to obtain high precision pixel characteristics as the basis for measuring the flatness for cultural products' structure, and extracts image features of cultural products and carries out matching process to establish an image detection model for flatness measurement. The experimental results show that the proposed algorithm greatly improves the accuracy of flatness measurement for cultural product structure.

Abstract: The steel tube-plate joints are widely applied in tall-slender tower of transmission line engineering,but there are few studies at home and abroad. In this paper,experimental study with full-scale model and analysis based on FEM were carried out on the ultimate bearing capacity of typical h-joints , and the results showed that the bending moment was transferred to the chord from the ear-plate of a narrow area, which led to local buckling on the chord wall , so the local strength of chord is one of the most important control factors in the design of this typical joint;thus the bearing capacity can improve by enhancing the strength of steel or increasing the thickness of ear-plate. In view of the phenomenon that stress concentration is easy to emerge at the intersection of the steel tube-plate joints, some improvement measures for the connections are put forward,such as adding outer half-ring stiffening plates , adding outer-ring plates , adding inner-ring plates, and revising ear-plates to smooth the concave angle , etc.