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991.
Examines the use of magnetic fields to functionally stimulate peripheral nerves. All electric fields are induced via a changing magnetic field whose flux is entirely confined within a closed magnetic circuit. Induced electric fields are simulated using a nonlinear boundary element solver. The induced fields are solved using duality theory. The accuracy of these predictions is verified by saline bath experiments. Next, the theory is applied to the stimulation of nerves using small, partially occluded ferrite and laminated vanadium permendur cores. Experiments demonstrate the successful stimulation of peripheral nerves in the African bullfrog with 11 mA, 153 mV excitations. These results offer a new vista of possibilities in the area of functional nerve stimulation. Unlike functional electric stimulation (FES), FMS does not involve any half cell reactions, and thus would not have the commensurate FES restrictions regarding balanced biphasic stimulation, strength duration balances, and oxidation issues, always exercising care that the electrodes remain in the reversible operating regime 相似文献
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在简单介绍了ADSL技术的基础上,具体介绍了如何在EWSDU交换机中创速和设置ADSL用户功能和xDSL功能. 相似文献
996.
某尾矿库周围环境中污染物生态转移研究 总被引:4,自引:0,他引:4
对我国某尾矿库周围环境中放射性核素U、^226Ra、Th及非放污染物Mn^2 、Cd、Cr、Pb在农作物和水生生物等介质中的浓集情况进行了现场研究,给出了相应的污染物生态学转移系数Bv和Bp值。 相似文献
997.
Duan Li Fucai Qian Peilin Fu 《Automatic Control, IEEE Transactions on》2002,47(12):2010-2020
998.
A system-on-chip (SOC) usually consists of many memory cores with different sizes and functionality, and they typically represent a significant portion of the SOC and therefore dominate its yield. Diagnostics for yield enhancement of the memory cores thus is a very important issue. In this paper we present two data compression techniques that can be used to speed up the transmission of diagnostic data from the embedded RAM built-in self-test (BIST) circuit that has diagnostic support to the external tester. The proposed syndrome-accumulation approach compresses the faulty-cell address and March syndrome to about 28% of the original size on average under the March-17N diagnostic test algorithm. The key component of the compressor is a novel syndrome-accumulation circuit, which can be realized by a content-addressable memory. Experimental results show that the area overhead is about 0.9% for a 1Mb SRAM with 164 faults. A tree-based compression technique for word-oriented memories is also presented. By using a simplified Huffman coding scheme and partitioning each 256-bit Hamming syndrome into fixed-size symbols, the average compression ratio (size of original data to that of compressed data) is about 10, assuming 16-bit symbols. Also, the additional hardware to implement the tree-based compressor is very small. The proposed compression techniques effectively reduce the memory diagnosis time as well as the tester storage requirement. 相似文献
999.
Gillespie J.K. Fitch R.C. Sewell J. Dettmer R. Via G.D. Crespo A. Jenkins T.J. Luo B. Mehandru R. Kim J. Ren F. Gila B.P. Onstine A.H. Abernathy C.R. Pearton S.J. 《Electron Device Letters, IEEE》2002,23(9):505-507
The low temperature (100°C) deposition of Sc2O3 or MgO layers is found to significantly increase the output power of AlGaN/GaN HEMTs. At 4 GHz, there was a better than 3 dB increase in output power of 0.5×100 μm2 HEMTs for both types of oxide passivation layers. Both Sc2 O3 and MgO produced larger output power increases at 4 GHz than conventional plasma-enhanced chemical vapor deposited (PECVD) SiNx passivation which typically showed ⩽2 dB increase on the same types of devices. The HEMT gain also in general remained linear over a wider input power range with the Sc2O3 or MgO passivation. These films appear promising for reducing the effects of surface states on the DC and RF performance of AlGaN/GaN HEMTs 相似文献
1000.
LIU Li xinEngineer Design Institute Changjiang Water Resources Commission Wuhan China CHANG Han junEngineer Design Institute Changjiang Water Resources Commission Wuhan China 《人民长江》2001,(Z1)
1 OverviewTheGeheyanPowerStationhasfourcircularinlettun nels,ontherightbankofdamsite,withtheirexcavationdi ameterof 11.3mto 12.5m,after liningdiameterof 9.5m,axis to axisspacingof2 4m.Thethicknessofpillarsareequaltothetunneldiameter.Theintakecenterisateleva ti… 相似文献