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As an effective access to sources of information, the education in the 21st century is characterized by the extensive application of information technology. With a lot of advantages, IT application to P.E. teaching reform has become one of the most important topics. In this paper, based on theoretical and practical analysis, it suggests that at present stage, problems are quite apparent in applying IT to P.E. such as outdated ideas about education, shortage of fund and high-quality teachers, neglect of the dominant position of students and so on. Concerning these problems, corresponding countermeasures are put forward, including changing ideas about education, increasing investment, providing technical support, strengthening training of the teacher and establishing the informationized teaching mode of “student-centered, teacher-led”.

In this paper, the conformal mapping problem on the transformation from the interior of a unit circle to the interior of the simply connected region or exterior with an arbitrary curvilinear boundary (including an arbitrary curvilinear cut crack) is discussed. The boundary of the simply connected region is approximated by a polygon. The mapping function from a unit circle to a polygon is founded by using the Schwartz-Christoffel integral. A numerical calculation method to determine the unknown parameters in the Schwartz-Christoffel integral is given.

An improved off-line robust model predictive control (MPC) is presented for a discrete time uncertain dynamic system with input constraints, where the uncertainties that satisfy the so-called norm-bound conditions exist in state matrices and input matrices. The new approach synthesizes the advantage of on-line MPC and off-line MPC. First, off-line, generate a sequence of asymptotically stable invariant ellipsoids one inside another near the origin, and a sequence of explicit control laws corresponded with these invariant ellipsoids. Second, on-line, judge whether the current state is in these ellipsoids. If in, apply off-line the control law corresponded. If out, apply the on-line robust MPC with N-step free control moves. The main advantage of this new approach with respect to other well-known technique is the guaranteed robust stability, the guaranteed performance, and the reduced computation. This makes robust MPC a very attractive control methodology for application to large scale systems and fast processes. The performance of the controller is demonstrated by an example.

This paper presents a nonlinear disturbance observer-based finite time convergent second order sliding mode control scheme for a tailless aircraft with uncertain parameters. Command angles and angular rate commands are robustly tracked in outer and inner loops correspondingly via finite time convergent second order sliding mode controllers. Nonlinear disturbance observer is employed to retain overall high accuracy of the closed-loop tracking. An optimal control allocation algorithm is employed using nominal mathematical model of an aircraft. The control approach is applied to the innovative control effectors (ICE) fighter aircraft. Computer simulations demonstrate high accuracy tracking performance.

This paper proposes a new guidance law for the impact angle control, using the variable structure control theory. The guidance law has the ability to simultaneously achieve design specifications on miss distance and final missile-target relative orientation. The latter specification may be used to enhance the performance of warheads whose effectiveness is influenced by the terminal encounter geometry between missile and target. The variable structure guidance law is parameterized with terminal conditions of miss distance and terminal encounter angle. Feasibility of the variable structure guidance law is demonstrated by the simulation. According to the simulation results, the guidance law is shown to perform well against an air target performing evasive maneuvers. The specified zero aspect terminal encounter angle is achieved while simultaneously minimizing the miss distance.

A fault tolerant flight controller based on adaptive and conditional integral sliding mode control scheme for an aircraft with actuator faults is developed. Sliding mode controller (SMC) which has good performance for the systems with various uncertainties is used to deal with the actuator faults. Due to imperfect switching in practice, SMC raises the issue of chattering. When implemented using boundary layer, the controller can no longer guarantee zero steady-state error. In this study, (i) a conditional integral term is introduced to achieve zero steady-state error and (ii) the adaptive technique based on Lyapunov stability theory is adopted to compensate the effects of the disturbance generated by actuator faults. Numerical simulation results demonstrate high accuracy tracking performance via adaptive conditional integral sliding mode controllers without the fault detection and isolation process.

This paper proposes a new three-dimensional (3D) guidance law for the impact angles control, using the variable structure control theory. In order to study the problem of the precision guidance, the three-dimensional terminal motion of air-crafts is divided into the motion in the vertical plane and the bank plane. Then the decoupling control of the guidance law is designed independently. After the linear optimal guidance laws are designed with terminal multi-constraint conditions of miss-distance, impact trajectory inclination angle and impact trajectory rotation angle, we let the linear optimal model act as the referenced model and take the linear optimal input as the reality system's referenced input. According the model matching condition, the guidance parameters are updated by variable structure laws to ensure high precision in the impact angle conditions. Some simulations of the characteristic trajectory are performed. The simulation's results show the variable structure guidance law based on adaptive model-following control is not only satisfied with the need of precision guidance and impact angular constraints, but also have excellent trajectory in terminal guidance.

RoboCup is an increasingly developed international high-tech based match to promote AI, robotics, and related fields. As an item of the whole project, the small-size group is a hardware based match. This paper discusses the robots system implement of such a match. At first, we introduce the RoboCup match and the research of our country. Then the small-size group rules are given in brief. After this, two main architectures of the implement are analyzed: the global vision system and the distributed vision system. At last, based upon above analysis,we bring forward our implement: an omni-direction based global vision system, and indicate the future work.

The Robot World Cup is the largest mobile robot event and the most important international conference on AI and robotics at present. RoboCup is an attempt to promote AI and robotics research by providing a common task for evaluation of various theories, algorithms, and agent architectures. This paper studies the theoretical and technical issues of the application of the expert system for robot planning theory to RoboCup. This paper gives a primary introduction of the expert system and the robot planning, the content includes the theory of the robot planning based on expert system and the framework of the system that based on the theory. Finally, its application of the framework to RoboCup and how machine learning can be integrated in the system are also studied in this paper.

As a standard research platform of artificial intelligence and robotics, RoboCup is gathering more and more attention. Because in the match, the environment is dynamically changing, the method of machine learning is widely used. An important problem is how to reduce the complex environment in learning, so that the number of states is decreased. The paper briefly introduces Soccer Server. Then several methods of constructing the state space are analyzed. A method of reduction of the state space is described. The method divides the environment around the client into some regions which are not equal in size. The state space is constructed with these regions.

Most practical control problems are dominated by constraints. Although a rich theory has been developed for the robust control of linear systems, very little is known about the robust control of linear systems with constraints. Over the years various model-based algorithms (given a generic term Model Predictive Control) have been used in industry to control complex multivariable systems with operating constraints. The design and tuning of these controllers is difficult for two reasons: 1. Process models are always inaccurate which implies that the controllers must be robust. 2. Even in the simplest case where process models are linear, the overall systems are nonlinear because of the constraints. Despite Model Predictive Control's considerable practical importance, there is very little theory to guide the design and tuning of these controllers for stability and robustness. It is the goal of this thesis to develop such a theory. Specifically, a general framework based on Model Predictive Control is developed to synthesize controllers for discrete-time linear systems subject to constraints with robust stability and performance guarantees.

Imaging properties of two-dimensional photonic crystal slab lens consisting of a triangular lattice of ring-shaped air holes in a high-refraction-index dielectric medium have been studied. The results calculated by the plane wave expansion method （PWE） and the finite-difference time-domain method （FDTD） show that the effective index n=-1 can be realized in this structure. A perfect image can be obtained by increasing the inner radius of ring-shaped holes from 0 to 0.13a with the outer radius 0.4a at the normalized frequency 0.3（a/λ）. Based on the result of normalized frequency with effective refraction index -1 versus inner radius of ring-shaped holes we theoretically analyzed the effects of structure parameters to equifrequency contours of respective normalized frequency and imaging properties.

The absorption and upconversion fluorescence spectra of Er3+ ions in Er3+ doped transparent lead lanthanum zirconate titanate(PLZT)ceramic were measured at room temperature. The radiative transition probabilities of the Er3+ ions were calculated using the absorption spectrum of Er3+ doped PLZT. Strong upconversion emission was observed in the upconversion luminescence of Er3+ doped PLZT. The green emission intensities at 540nm and 564nm were stronger than the red emission intensity at 678nm. The upconversion rate equations describing the dynamic process of the system have been deduced. The upconversion coefficients were estimated by numerically solving the rate equations and fitting the simulated curves to the measured data. The coefficients C22and C33 obtained are 091×10-18cm3/s and 1823×10-18cm3/s, respectively. The results show that evident upconvesion phenomenon can be observed in Er3+: PLZT transparent ceramics, which is consistent with our observation.