An analytical expression of the peeling mode in the near separatrix region of diverted tokamak plasma is derived. It is shown that in diverted plasmas both with single and double X points, though the perturbed potenti...An analytical expression of the peeling mode in the near separatrix region of diverted tokamak plasma is derived. It is shown that in diverted plasmas both with single and double X points, though the perturbed potential energy of the unstable peeling mode tends to be large, its growth rate becomes very small due to the even larger kinetic energy. Compared to some recent studies that give qualitatively correct results about this growth rate, our result is directly related with the diverted equilibrium quantities suitable for application to realistic experiments.展开更多
A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picose...A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picosecond pulse output with an average power of 1.38 W, a repetition rate of 3.24 GHz, and a pulse duration of 11.4 ps is achieved. After one stage of amplification, the final output power reaches 11.34 W, corresponding to a total optical-to-optical efficiency of about 32%. The root mean square(RMS) value of power fluctuation is demonstrated to be less than 0.6% in 24 hours,showing a superior stability with the compact configuration.展开更多
The annual subduction rate in the South Indian Ocean was calculated by analyzing Simple Ocean Data Assimilation （SODA） outputs in the period of 1950-2008. The subduction rate census for potential density classes sho...The annual subduction rate in the South Indian Ocean was calculated by analyzing Simple Ocean Data Assimilation （SODA） outputs in the period of 1950-2008. The subduction rate census for potential density classes showed a peak corresponding to Indian Ocean subtropical mode water （IOSTMW） in the southwestern part of the South Indian Ocean subtropical gyre. The deeper mixed layer depth, the sharper mixed-layer fronts and the associated relatively faster circulation in the present climatology resulted in a larger lateral induction, which primarily dominants the IOSTMW subduction rate, while with only minor contribution from vertical pumping. Without loss of generality, through careful analysis of the water characteristics in the layer of minimum vertical temperature gradient （LMVTG）, the authors suggest that the IOSTMW was identified as a thermostad, with a lateral minimum of low potential vorticity （PV, less than 200× 10^-12 m^-1·s^-1） and a low dT/dz （less than 1.5℃/（100 m））. The IOSTMW within the South Indian Ocean subtropical gyre distributed in the region approximately from 25° to 50° E and from 30° to 39°S. Additionally, the average characteristics （temperature, salinity, potential density） of the mode water were estimated about （16.38 ± 0.29）℃, （35.46 ±0.04）, （26.02 ±0.04） ae over the past 60 years.展开更多
基于心率变异性(HRV)的特征分析,提出一种患者阵发性房颤(PAF)发作的预测系统方法。首先,基于一种新的自适应滤波技术逐次平滑滤波并粗粒化HRV后,采用熵量化HRV在多个自适应尺度的复杂性特征;其次,特征经MinMax归一化和序列前向选择特...基于心率变异性(HRV)的特征分析,提出一种患者阵发性房颤(PAF)发作的预测系统方法。首先,基于一种新的自适应滤波技术逐次平滑滤波并粗粒化HRV后,采用熵量化HRV在多个自适应尺度的复杂性特征;其次,特征经MinMax归一化和序列前向选择特征子集,输入支持向量机识别HRV类型,预测PAF发作。经50例时长5 min HRV序列集的五折交叉验证,得到最优预测结果为:准确率98%,敏感性100%,特异性96%,性能表现优越。另外,实验表明远离和紧随PAF时的HRV复杂性特征值在不同频率段内,分别具有不同的显著变化(P<0.05),反映受试者神经系统调节心脏节律改变,以及调控机体、应激等适应外界环境变化能力的下降。展开更多
基金Project supported by the National Magnetic Confinement Fusion Science Program of China （Grant No. 2009GB 101002）.
文摘An analytical expression of the peeling mode in the near separatrix region of diverted tokamak plasma is derived. It is shown that in diverted plasmas both with single and double X points, though the perturbed potential energy of the unstable peeling mode tends to be large, its growth rate becomes very small due to the even larger kinetic energy. Compared to some recent studies that give qualitatively correct results about this growth rate, our result is directly related with the diverted equilibrium quantities suitable for application to realistic experiments.
基金Project supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB16030200)the National Natural Science Foundation of China(Grant Nos.11774410 and 61575217)+1 种基金the National Key Scientific Instruments Development Program of China(Grant No.2012YQ120047)the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(Grant No.KJZD-EW-L11-03)
文摘A compact high power diode-pumped passively mode-locked Nd:YVO_4 laser with high repetition rate is realized.Using an Nd:YVO_4 crystal and a semiconductor saturable absorber mirror(SESAM) in the oscillator, the picosecond pulse output with an average power of 1.38 W, a repetition rate of 3.24 GHz, and a pulse duration of 11.4 ps is achieved. After one stage of amplification, the final output power reaches 11.34 W, corresponding to a total optical-to-optical efficiency of about 32%. The root mean square(RMS) value of power fluctuation is demonstrated to be less than 0.6% in 24 hours,showing a superior stability with the compact configuration.
基金The National Natural Science Foundation of China under contract Nos 41276011 and 41221063the Research Project of Chinese Ministry of Education under contract No.113041Athe Global Change and Air-Sea Interaction under contract under contract No.GASI-03-01-01-05
文摘The annual subduction rate in the South Indian Ocean was calculated by analyzing Simple Ocean Data Assimilation （SODA） outputs in the period of 1950-2008. The subduction rate census for potential density classes showed a peak corresponding to Indian Ocean subtropical mode water （IOSTMW） in the southwestern part of the South Indian Ocean subtropical gyre. The deeper mixed layer depth, the sharper mixed-layer fronts and the associated relatively faster circulation in the present climatology resulted in a larger lateral induction, which primarily dominants the IOSTMW subduction rate, while with only minor contribution from vertical pumping. Without loss of generality, through careful analysis of the water characteristics in the layer of minimum vertical temperature gradient （LMVTG）, the authors suggest that the IOSTMW was identified as a thermostad, with a lateral minimum of low potential vorticity （PV, less than 200× 10^-12 m^-1·s^-1） and a low dT/dz （less than 1.5℃/（100 m））. The IOSTMW within the South Indian Ocean subtropical gyre distributed in the region approximately from 25° to 50° E and from 30° to 39°S. Additionally, the average characteristics （temperature, salinity, potential density） of the mode water were estimated about （16.38 ± 0.29）℃, （35.46 ±0.04）, （26.02 ±0.04） ae over the past 60 years.
文摘基于心率变异性(HRV)的特征分析,提出一种患者阵发性房颤(PAF)发作的预测系统方法。首先,基于一种新的自适应滤波技术逐次平滑滤波并粗粒化HRV后,采用熵量化HRV在多个自适应尺度的复杂性特征;其次,特征经MinMax归一化和序列前向选择特征子集,输入支持向量机识别HRV类型,预测PAF发作。经50例时长5 min HRV序列集的五折交叉验证,得到最优预测结果为:准确率98%,敏感性100%,特异性96%,性能表现优越。另外,实验表明远离和紧随PAF时的HRV复杂性特征值在不同频率段内,分别具有不同的显著变化(P<0.05),反映受试者神经系统调节心脏节律改变,以及调控机体、应激等适应外界环境变化能力的下降。
