Advanced Materials Research Vols. 268-270

Abstract: Based on the model of induction motors in field-oriented coordinates, a block adaptive backstepping method is used to design a controller for induction motor. The control law and parameter updating law are derived using Lyapunov theory, which guarantees the stability of the whole system. The proposed approach can track the rotor speed and flux reference signals under parameter and load uncertainties. Simulation results show the effectiveness of the proposed approach.

Abstract: Decision support systems provide the field of query optimization with increasing challenges in the traditional questions of selectivity estimation that can exploit transformations without exploding search space. The aims of this paper are to understand what the data warehouse and protect the sensitive information stored elsewhere in data warehouse. In the system, management level of system can review all records of historical data for monthly or yearly as user desired item for each dimension. This system is developed to easy access for frequently needed data, to improve end-user respond time. The paper results in accumulation of growing amounts of data in operational databases. The system can help to retrieve complex query analysis report. In this paper, we analyze personnel information by using Data Warehouse and OLAP tools.

Abstract: The energy consumption of WLAN card makes up a significant proportion in the embedded system, which makes the effective power management on WLAN card play an important role on energy-saving and WLAN card longevity. This paper introduces a method of dynamic power management for WLAN card: manipulating the WLAN card driver to achieve the transition state of the WLAN card, acquiring WLAN card load which ultimately achieves the dynamic power management optimization algorithm. The experiment is presented to prove the feasibility of the implementation for the purpose of energy consumption saving on WLAN card.

Abstract: Aircraft Electrical Load Management Center, an important part of the aircraft power supply system, solves the automatic management of aircraft load via a multi-channel transmission bus and a solid-state power controller. Using micro-computer technology, instead of manual operation, for automatic control and management of the load has improved the existing method of distribution and load management, which has enhanced performance of aircraft and its maintenance of power system. This paper studies the overall structure and composition principle of ELMC and details ELMC’s functions of each component modules and the implementation of hardware and software. System test results show that the automatic load management techniques greatly improve the aircraft power system reliability and maintainability.

Abstract: This paper introduces that embedded real time operating system μC/OS-II is applied in software design of aircraft electrical load management center. Firstly, the μC/OS-II and its running on ARM are briefly presented. Then the method of two system running modes is given in details. And the tasks assignment, priority allocation and communication between tasks under both two modes are also provided. Results show that multitask schedule managements of real-time system has solved the problem of poor real-time in a single task system. And the reliability of the system has been greatly improved.

Abstract: The train and the continuous truss girder bridge are coupled together as one composite system. Truss girder bridge is idealized as an assemblage of finite truss element. The equations of the train and truss girder bridges time varying system are set up by using the principle of total potential energy with stationary value in elastic system dynamics and the“set-in-right-position”rule for forming structural matrices. This method is more convenient than the finite elements. The vibration responses of the train and bridge are calculated when the the passenger trains pass through a continuous truss girder bridge at speeds of 90km/h and 120km/h The results show that the passenger train can pass it safely and comfortably

Abstract: Language learners are not machines to be programmed but people with likes and dislikes, weaknesses and prejudices. This paper intends to discuss the affective factor --motivation of language learners. The author surveys motivation with the focus on the classification of intrinsic motivation and extrinsic motivation and compares their different influences on senior high school students. Anyway, the author aims to provide some suggestions and first-hand datum for high school English teaching.

Abstract: The paper will introduce the processsing principle of the stator(the major parts of the toroidal planet gear driving ).then taking pro /e as tool ,setablishing the full –scale process modeling of the stator by the new method –VRM .

Abstract: The on-orbit servicing task allocation is very important to improve the cooperative work ratio of the on-orbit servicing spacecraft. A discrete particle swarm optimization (DPSO) algorithm is put forward for on-orbit servicing spacecraft cooperative task allocation problems. A new code of particles and new update strategy for the position and speed of particles are applied. By analyzing the critical index factors which contain target spacecraft value, servicing spacecraft attrition and energy-time consumption, on-orbit spacecraft task allocation model is formulated. The simulation results show that the DPSO algorithm has fast convergence, optimization capability, and can solve the on-orbit servicing spacecraft cooperative task allocation effectively.

Abstract: By taking NACA0012 airfoil as the research object，the pressure distribution is given，based on the simulation of airfoil fieldflow field with ANSYS. Each modal characteristic is visually display ，by analysis on vibration modal of airfoil