No abstract

As a main industry of our national economy, petrochemical industry produces long-lasting industrial waste gas, waste water and waste residues which affect ecological environment in our country seriously. The eco-efficiency rate is a significant indicator in evaluation industrial sustainable development, which represents the efficiency of alleviation pressure on the environment using natural resources in the economic growth. So, in this paper, we used three-stage DEA model to evaluate the eco-efficiency of the petrochemical industry. The empirical analysis shows that it is feasible to use the three-stage DEA model on evaluation the eco-efficiency of the petrochemical industry.

Bridge-type flexure hinge is a classical flexure amplification mechanism. The amplification ratio and stiffness are the key parameters in an amplification mechanism. Elastic mechanics was used to analyze the input and output stiffness of bridge-type amplification mechanism in relation to the translational and rotational stiffness of the flexure pivots. The result showed that the stiffness model can explain well the outer characteristic of bridge-type flexure hinge.

A crab-like octopod robot is introduced in this paper. The body structure of the robot is simuliar with a real crab. Each leg has three jionts which are driven by servomotors. The control system is a distributed hierarchical system with a top layer as gait generator and a bottom layer as servomotor controller. The bottom layer has enght individual control units every of which can control three servomotors using PID control method. The sensor systerm is composed of force sensors mounted at the end of the leg and a inclinometer provides pitch and roll angles of the body.