Cheng Y.,Hunan Institute of Humanities, Science and Technology |
You X.,Loudi Vocational and Technical College |
Xiao M.,Hunan Institute of Humanities, Science and Technology
ITME 2011 - Proceedings: 2011 IEEE International Symposium on IT in Medicine and Education | Year: 2011
DS (Diamond Search) is one of the most famous motion estimation algorithms. By analyzing the characteristics of DS, it is found that DS can be improved more efficiently. A Modified Diamond Search (MDS) algorithm is proposed in this paper. Firstly, MDS employs Small Diamond Search Pattern(SDSP) to judge if the MBD(Minimum Block Distortion) point is the initial search center. If the MBD point does not locate at the search center, Simplified Large Diamond Search Pattern(SLDSP) will be used in the next search step. If the MBD point is not within the circular area with a radius of one pixel, SLDSP will be employed continually to locate the best matching block with large motion vector until the search center become the MBD point. Finally SDSP will be adopted to refine the motion vector. Experimental results show that MDS can speed up the motion estimation process greatly under the same encoding efficiency compared to DS, especially for those video sequences with simple and slow motion vectors. © 2011 IEEE.
Li H.,Loudi Vocational and Technical College |
Li R.,Chongqing SANY Highintelligent Robots Co.
Mathematical Problems in Engineering | Year: 2015
A free-floating space manipulator is an underactuated system, of which the spacecraft is permitted to rotate freely in response to the manipulator motions. The dynamic coupling property between the spacecraft and the manipulator makes motion control of such systems a significant challenge. In the paper, a zero-disturbance control method for free-floating space manipulators operating in task space is presented. An explicit direct relationship between the spacecraft attitude quaternions and the manipulator joint variables is established using nonholonomic constraints of the angular momentum conservation. By this means the kinematic redundancy of the system is used to adjust the spacecraft attitude. An integral-type sliding mode controller with adaptive switching gains is developed for coordinated motion control of the spacecraft and the manipulator. Simulations on three-link planar model show that the spacecraft remains undisturbed during the whole process of manipulations, which confirms the effectiveness of the proposed method. © 2015 Heping Li and Ren Li.
Bao S.,Loudi Vocational and Technical College
Advanced Materials Research | Year: 2011
As the internet technology develops, the application of mobile RFID becomes more and more common. Since mobile RFID label is easier to be read and attacked by hacker, personal information of the users is leaked. Present authentication mechanisms in application are either made into RFID hardware with complex design or with weaker security protection ability. The paper proposes a new security authentication mechanism and the test result shows that the authentication mechanism may effectively prevent various attack behaviors of hack with the base of low cost so as to reach the objective of protecting personal privacy of card holder. © (2011) Trans Tech Publications, Switzerland.
Xie W.,Loudi Vocational and Technical College |
Dai Y.,Hunan University
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2011
A flux modulation method is designed based on the fast on-off concept of switching power supply for current transducer. Its secondary winding is consisted of main winding and control winding. The flux in the current transducer is modulated by the switching frequency and duty-cycle of control winding, and the induced voltage of main winding is changed accordingly. Simulative and experimental results show the method efficiently reduces induced voltage, which proves that the proposed method can be applied to floating power design.
Guojian Z.,Loudi Vocational and Technical College
Research Journal of Applied Sciences, Engineering and Technology | Year: 2013
This design has been made the module division according to its function. It including video display, three party service (volume control) and environment parameters display warning information as well as data storage module. Furthermore, this application software uses the multithreading to realize the modulation, which including the receive thread (It receives the video and audio data as well as environment parameters data), the display thread and the warning judgment thread. This application software construction is based on the S3C6410 platform with embedded WinCE 6.0 operating systems in the VS2005 development environment to realize the system function. From the above, it can transfer the environment, the video and audio information to the rescuer and the underground base and the rescue command center instantaneously and accurately. In a word, it's helpful for command center to know underground rescue situations instantaneously and can implement command well. © Maxwell Scientific Organization, 2013.