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81.
Orderly stimulation of skeletal muscle motor units with tripolarnerve cuff electrode 总被引:4,自引:0,他引:4
Baratta R. Ichie M. Hwang S.K. Solomonow M. 《IEEE transactions on bio-medical engineering》1989,36(8):836-843
An electrical nerve stimulation technique, using single tripolar electrode, was shown to be capable of recruiting motor units according to their size, while allowing simultaneous but independent control of firing rate in the active units. Test paradigms consisting of established fundamental physiological concepts of soleus-gastrocnemius architecture, motor units conduction velocity, firing rate behavior of motor units of different sizes, and their susceptibility to fatigue were employed to validate the technique and demonstrate its utility as a basic and applied research tool. 相似文献
82.
A drag-link drive of mechanical presses for precision drawing 总被引:1,自引:0,他引:1
W. M. Hwang Y. C. Hwang S. T. Chiou 《International Journal of Machine Tools and Manufacture》1995,35(10)
The augmented Lagrange multiplier method has been used to synthesize the dimensions of a drag-link drive of mechanical presses for precision drawing. The objective functions include the maximum normal force on the guide, mean mechanical advantage, variance of the drawing velocity, etc. The constraints include the working velocity for drawing, variance of the working velocity for precision drawing, time ratio, etc. Based on the concept of kinematic coefficients, a method is proposed to provide suitable initial guesses of the optimization. The drag-link drive thus synthesized has performance superior to an existing press for precision drawing. 相似文献
83.
The authors propose an efficient traceback scheme for the parallel hardware implementation of the Viterbi algorithm. Compared to the conventional Viterbi algorithm, where output is selected arbitrarily when multiple survivor paths exist, the proposed algorithm decides decoding output by analysing the survivor paths of consecutive tracebacks. Experimental results show that the proposed algorithm exhibits improved error-correction capability compared to the existing algorithms 相似文献
84.
85.
Kang Ji-Hoon Hwang Jinyul Sung Hyung Jin Ryu Hoon 《The Journal of supercomputing》2021,77(9):9597-9614
The Journal of Supercomputing - Direct numerical simulations (DNS) of turbulent flows have increasing importance because they not only provide fundamental understanding of turbulent flows but also... 相似文献
86.
Yoon-Sik Tak Seungmin Rho Eenjun Hwang Hanku Lee 《Multimedia Tools and Applications》2012,61(1):51-68
Dominant features for the content-based image retrieval usually have high-dimensionality. So far, many researches have been done to index such values to support fast retrieval. Still, many existing indexing schemes are suffering from performance degradation due to the curse of dimensionality problem. As an alternative, heuristic algorithms have been proposed to calculate the answer with ??high probability?? at the cost of accuracy. In this paper, we propose a new hash tree-based indexing structure called tertiary hash tree for indexing high-dimensional feature data. Tertiary hash tree provides several advantages compared to the traditional extendible hash structure in terms of resource usage and search performance. Through extensive experiments, we show that our proposed index structure achieves outstanding performance. 相似文献
87.
Goo-Rak Kwon Chuntao Wang Shiguo Lian Suk-seung Hwang 《Multimedia Tools and Applications》2012,59(3):885-895
In this paper, we propose an advanced partial encryption of watermarking and scrambling using the magnitude information of Modifed Discrete Cosine Transform (MDCT). In MPEG-1/Audio Layer III (MP3), the magnitude and phase information of modified discrete cosine transform (MDCT) coefficients is encrypted. The proposed method uses both watermarking and scrambling, and aims at protecting the contents against eavesdropping and moreover against illegal mass distribution after descrambled. Experimental results show that the proposed method can achieve higher security and less computational complexity by reusing the MDCT coefficients obtained in MP3. 相似文献
88.
Faa‐Jeng Lin Jonq‐Chin Hwang Kuang‐Hsiung Tan Zong‐Han Lu Yung‐Ruei Chang 《Asian journal of control》2012,14(3):768-783
An intelligent control for a stand‐alone doubly‐fed induction generator (DFIG) system using a proportional‐integral‐derivative neural network (PIDNN) is proposed in this study. This system can be applied as a stand‐alone power supply system or as the emergency power system when the electricity grid fails for all sub‐synchronous, synchronous, and super‐synchronous conditions. The rotor side converter is controlled using field‐oriented control to produce 3‐phase stator voltages with constant magnitude and frequency at different rotor speeds. Moreover, the grid side converter, which is also controlled using field‐oriented control, is primarily implemented to maintain the magnitude of the DC‐link voltage. Furthermore, the intelligent PIDNN controller is proposed for both the rotor and grid side converters to improve the transient and steady‐state responses of the DFIG system for different operating conditions. Both the network structure and online learning algorithm are introduced in detail. Finally, the feasibility of the proposed control scheme is verified through experimentation. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
89.
Jeong Won Kim Hee Won Kang Dong-Hwan Hwang Sang Jeong Lee 《International Journal of Control, Automation and Systems》2012,10(3):529-535
A signal tracking method of GNSS receivers for spinning vehicles is proposed in order to eliminate the influence of spinning to the GNSS signal of a vehicle. In the proposed method, a rotation tracking loop is added into the carrier tracking loop of a conventional GNSS receiver. The proposed method was verified through computer simulations and an experiment for live GPS signals. The results show that the proposed method gives an accurate tracking performance. 相似文献
90.
The effect of calcination on the characteristics and sintering behaviour of zirconia-toughened alumina (ZTA) composite powders has been investigated. TiO2 was selected as an additive to promote the sinterability of ZTA powders. The starting materials were Al2O3 powder, Zr(OC3H7)4 and Ti(OC3H7)4, and homogeneous ZTA powder containing Zr-O-Ti bonding was prepared. Calcination affected the tetragonalmonoclinic phase transformation temperature of ZrO2 crystallizing from the gels. Calcination improved the densification rate of ZTA powder compact during sintering, which was attributed to the optimal ZrO2 particle size and distribution on the surface of alumina. A ZTA specimen with high bulk density and high tetragonal ZrO2 content was obtained under the conditions of 850°C/1 h calcination and 1500°C/1 h sintering. 相似文献