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351.
FEI Zhi-min DING Zhao-qi ZHANG Jue CUI Hua LI Xue-ming ZHOU Cai-fang SHU Guo-wei ZHOU Zheng-wen WANG Yong 《上海交通大学学报(医学英文版)》2007,19(2):100-103
Objective To study direct cortical electrical stimulation technique for the recording of motor evoked potentials under general anesthesia in central sulcus lesions. Methods The largest N20-P25 response was recorded from postcentral gyrus by intraoperative monitoring of cortical motor evoked potentials in 10 patients with intracranial lesions near or in the central area. The muscles of upper extremity in all patients were activated by delivering stimulus to cortical areas continuously. Moving the cortical electrodes forward, the largest P20-N25 response, SEP phase reversal,was obtained as a motor center stimulus. In this site of cortex, a short train stimulation elicited reproducible muscle action potentials that could be observed from the oscilloscope without averaging.Results MEPs can be recorded, pre- and post-operatively, without motor deficits of upper limbs in all patients.Conclusion This technique seems to be preferable for intraoperative localization of motor evoked potentials in central sulcus lesions under total intravenous anesthesia. 相似文献
352.
Regularization Method to the Parameter Identification of Interfacial Heat Transfer Coefficient and Properties during Casting Solidification 总被引:1,自引:0,他引:1
The accurate material physical properties, initial and boundary conditions are indispensable to the numerical simulation in the casting process, and they are related to the simulation accuracy directly. The inverse heat conduction method can be used to identify the mentioned above parameters based on the temperature measurement data. This paper presented a new inverse method according to Tikhonov regularization theory. A regularization functional was established and the regularization parameter was deduced, the Newton-Raphson iteration method was used to solve the equations. One detailed case was solved to identify the thermal conductivity and specific heat of sand mold and interfacial heat transfer coefficient (IHTC) at the meantime. This indicates that the regularization method is very efficient in decreasing the sensitivity to the temperature measurement data, overcoming the ill-posedness of the inverse heat conduction problem (IHCP) and improving the stability and accuracy of the results. As a general inverse method, it can be used to identify not only the material physical properties but also the initial and boundary conditions' parameters. 相似文献
353.
以高速铁路WJ-7 B型扣件胶垫为研究对象,通过动态力学性能试验测试了扣件胶垫在不同温度下的动力性能;结合温频等效原理、Williams-Landel-Ferry方程和高阶分数导数FVMP模型表征了扣件胶垫的黏弹性力学特性;将该模型代入建立的桥梁振动与结构噪声预测有限元-边界元模型,并与Kelvin-Vogit模型对比... 相似文献
354.
北京地铁8号线天桥站一永定门外站区间隧道施工过程中,盾构需要于K34+ 422.094 ~+ 534.308处近距离侧穿永定门西桥,穿越段地层以砂卵石地层为主.隧道在施工至K34+ 506.308里程时,距永定门桥最近处仅9.2m,施工对桥梁影响较大,故有必要对盾构施工引发的桥梁结构安全进行评估.根据对盾构侧穿桥梁基础... 相似文献
355.
钢板桩围堰的设计与施工 总被引:5,自引:0,他引:5
本文就某桥基础施工采用的钢板桩围堰,按照理论计算方法进行了钢板桩围堰设计,并通过施工对设计结果进行了验证。 相似文献
356.
Virtual reality-based surgery simulation is becoming popular with the development of minimally inva-sive abdominal surgery,where deformable soft tissue is model... 相似文献
357.
To improve the signal detection performance of binary-sequence frequency hopping communication when the complementary channel is jammed,a binary-sequence freque... 相似文献
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