This paper describes the ocean loading tides corrections of GPS stations in Antarctica, such as the Great Wall station and Zhongshan station. Based on the theory of ocean loading tides, the displacement corrections of...This paper describes the ocean loading tides corrections of GPS stations in Antarctica, such as the Great Wall station and Zhongshan station. Based on the theory of ocean loading tides, the displacement corrections of ocean loading tides on GPS stations in Antarctica are calculated by using the CRS4.0 ocean loading tides model. These corrections are also applied to GPS data proc-essing. The GPS data are analyzed by the GAMIT software with and without these corrections. We compared and analyzed the GPS baseline components to get the differences. The results show that the ocean tidal displacement corrections have obvious effects upon GPS baseline components. Therefore, we should not ignore the ocean loading tides corrections of GPS stations in Antarctica to obtain precise and reliable results.展开更多
The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement pr...The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement principle for the motor is proved by experiments. The pulse waveforms are applied to drive the motor to move in steps. The motor has a displacement resolution of 10 nm and a maximum velocity of 0.6 mm/s. It can drive a 200 g slider whose range is 20 mm. A one-dimensional precision positioning platform is fabricated by using the new hybrid piezoelectric motor. The prototype is made up of two servomotors and two piezoelectric motors, which are controlled automatically by a computer. The positioning range of the platform is 10 cm.展开更多
The spatial position, seasonal variability and intensity of the main flow and the cyclonic circulation of the Black Sea waters along the axis of the divergence were identified. Corresponding calculations were done wit...The spatial position, seasonal variability and intensity of the main flow and the cyclonic circulation of the Black Sea waters along the axis of the divergence were identified. Corresponding calculations were done with using of the dynamic method and based on the climate data set of temperature and salinity for the surface and intermediate layers of the Black Sea. The important role of spring floods on the rivers of the northern-western Black Sea in the development of the water circulation features was shown because this river＇s water and main Black Sea current interact with the periphery of the western and eastern cyclonic circulation. This process is dominated at the western part sea surface cyclone： in spring and at eastern, in summer and autumn. The flow rate and nature of seasonal migration cyclonic centers were estimated. The results of research are based on a relatively large scale （40＇ latitude and 60＇ longitude） averaging and we have identified the main area of water divergence. Small, localized areas of convergence and divergence of flow that are presented in the Black Sea were not included into the scope of our research.展开更多
High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position con...High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position control of robot manipulators. However, parameter tuning method has not been proposed to finite-time P-PI control. In this paper, we propose a settling time design method and a parameter tuning method for the finite-time P-PI control. The effectiveness of the proposed parameter tuning method is confirmed by experiments of end-effcctor position control of a robot manipulator.展开更多
Extensibility and attainability of topology optimization are discussed by investigating a variety of simultaneous topology opti-mization methods extended from the standard formulation.First,the state of the art is hig...Extensibility and attainability of topology optimization are discussed by investigating a variety of simultaneous topology opti-mization methods extended from the standard formulation.First,the state of the art is highlighted through systematic classification of developed methods,such as simultaneous topology optimizations of microstructure and macrostructure,structure and supports,structure and design-dependent loads,structure and locations of involved components.Second,some recent results about simultaneous topology optimization of structure and applied loads are presented.It is shown that the simultaneous topology optimization is an integrated methodology that extends the concept of standard topology optimization in the sense of systematic design.The presence of more than one kind of design variable of different nature makes the optimization problem complex but enlarges the design space to attain the optimization.展开更多
基金the National 863 Program of China (No.2007AA12Z312)
文摘This paper describes the ocean loading tides corrections of GPS stations in Antarctica, such as the Great Wall station and Zhongshan station. Based on the theory of ocean loading tides, the displacement corrections of ocean loading tides on GPS stations in Antarctica are calculated by using the CRS4.0 ocean loading tides model. These corrections are also applied to GPS data proc-essing. The GPS data are analyzed by the GAMIT software with and without these corrections. We compared and analyzed the GPS baseline components to get the differences. The results show that the ocean tidal displacement corrections have obvious effects upon GPS baseline components. Therefore, we should not ignore the ocean loading tides corrections of GPS stations in Antarctica to obtain precise and reliable results.
文摘The motor’s configuration is designed and the dynamic analysis equations based on its simplified model are deduced. A testing system utilizing grating is set up to test this new motor, and the theoretical movement principle for the motor is proved by experiments. The pulse waveforms are applied to drive the motor to move in steps. The motor has a displacement resolution of 10 nm and a maximum velocity of 0.6 mm/s. It can drive a 200 g slider whose range is 20 mm. A one-dimensional precision positioning platform is fabricated by using the new hybrid piezoelectric motor. The prototype is made up of two servomotors and two piezoelectric motors, which are controlled automatically by a computer. The positioning range of the platform is 10 cm.
文摘The spatial position, seasonal variability and intensity of the main flow and the cyclonic circulation of the Black Sea waters along the axis of the divergence were identified. Corresponding calculations were done with using of the dynamic method and based on the climate data set of temperature and salinity for the surface and intermediate layers of the Black Sea. The important role of spring floods on the rivers of the northern-western Black Sea in the development of the water circulation features was shown because this river＇s water and main Black Sea current interact with the periphery of the western and eastern cyclonic circulation. This process is dominated at the western part sea surface cyclone： in spring and at eastern, in summer and autumn. The flow rate and nature of seasonal migration cyclonic centers were estimated. The results of research are based on a relatively large scale （40＇ latitude and 60＇ longitude） averaging and we have identified the main area of water divergence. Small, localized areas of convergence and divergence of flow that are presented in the Black Sea were not included into the scope of our research.
文摘High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position control of robot manipulators. However, parameter tuning method has not been proposed to finite-time P-PI control. In this paper, we propose a settling time design method and a parameter tuning method for the finite-time P-PI control. The effectiveness of the proposed parameter tuning method is confirmed by experiments of end-effcctor position control of a robot manipulator.
基金supported by the National Natural Science Foundation of China(Grant Nos.51275424,51221001)the National Basic Research Program of China("973"Project)(Grant No.2011CB610304)+1 种基金the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20126102130003)the NWPU Foundation for Fundamental Research(Grant No.NPU-FFR-201001)
文摘Extensibility and attainability of topology optimization are discussed by investigating a variety of simultaneous topology opti-mization methods extended from the standard formulation.First,the state of the art is highlighted through systematic classification of developed methods,such as simultaneous topology optimizations of microstructure and macrostructure,structure and supports,structure and design-dependent loads,structure and locations of involved components.Second,some recent results about simultaneous topology optimization of structure and applied loads are presented.It is shown that the simultaneous topology optimization is an integrated methodology that extends the concept of standard topology optimization in the sense of systematic design.The presence of more than one kind of design variable of different nature makes the optimization problem complex but enlarges the design space to attain the optimization.
