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线性门对模拟开关的选择与应用
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作者 杜先彬 张永明 +2 位作者 吴崑 阴泽杰 朱大鸣 《核电子学与探测技术》 CAS CSCD 北大核心 2005年第6期821-823,共3页
介绍了线性门的基本工作原理及对模拟开关的选用、集成模拟开关的有关参数和工作特性及其在用于线性门时对模拟信号传输的影响。
关键词 模拟开关 线性门 模拟信号传输
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14MeV脉冲中子非弹性散射γ谱的测量 被引量:6
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作者 李中伟 卢洪波 +3 位作者 郭景富 古力 杨喜峰 刘林茂 《物理实验》 北大核心 2002年第2期8-10,14,共4页
论述了中子和原子核相互作用的几种反应 ,利用各反应在时间上的差异 ,采用双门减本底的测量方法来测量非弹性散射 γ谱 .利用碳、氧的非弹性散射 γ射线能量高、能量差别大的特点 ,以碳、氧为指示元素测量水和石蜡的非弹性散射 γ谱 .... 论述了中子和原子核相互作用的几种反应 ,利用各反应在时间上的差异 ,采用双门减本底的测量方法来测量非弹性散射 γ谱 .利用碳、氧的非弹性散射 γ射线能量高、能量差别大的特点 ,以碳、氧为指示元素测量水和石蜡的非弹性散射 γ谱 .开设这一实验 。 展开更多
关键词 脉冲中子 非弹性散射 线性门 减本底 原子核 Γ谱 测量方法
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新疆晚奥陶世晚期管状体及其古植物学意义(英文) 被引量:2
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作者 王怿 李军 《微体古生物学报》 CSCD 北大核心 2001年第3期241-248,共8页
本文系统描述了产自我国新疆塔里木盆地晚奥陶世晚期的管状体 ,包括 2属 8种 ,其中一个新种。通过对比研究 ,本管状体组合与 Burgess和 Edwards( 1991)的下组合相当。根据本组合的研究 ,对 Burgess和 Edwards的组合进行了补充 ,其组合... 本文系统描述了产自我国新疆塔里木盆地晚奥陶世晚期的管状体 ,包括 2属 8种 ,其中一个新种。通过对比研究 ,本管状体组合与 Burgess和 Edwards( 1991)的下组合相当。根据本组合的研究 ,对 Burgess和 Edwards的组合进行了补充 ,其组合由不同类型的光壁管、低分异度的内壁加厚管组成 ,未见外壁加厚管和丝状体 ,组合的时代从中奥陶世到早志留世 (晚 L landovery)。根据植物学的对比研究 ,管状体主要产自 Nem atophytales L ang。 展开更多
关键词 管状体 晚奥陶世晚期 新疆 线性植物 古植物学
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STUDY ON NON LINEAR VIBRATION RESPONSE OF PLATE GATES *
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作者 练继建 杨敏 林继镛 《Transactions of Tianjin University》 EI CAS 1998年第1期14-18,共5页
This paper deals with the vertical vibration, the horizontal translatory and flexural vibrations of plate gate with a flat bottom under the action of unstable submerged underflow. Based on a non linear resonant oscil... This paper deals with the vertical vibration, the horizontal translatory and flexural vibrations of plate gate with a flat bottom under the action of unstable submerged underflow. Based on a non linear resonant oscillator model by which the coupled excitation mechanism between the unstable vortices and gate motion can be simulated, the differential equations for the three types of gate vibrations are established. The parameters in the equations are determined by model experiments. Then, the steady state non linear responses of the three types of gate vibrations are calculated. The calculation results are in good agreement with the experimental data of gate vibrations with different reduced velocity and gate parameters by previous researchers. 展开更多
关键词 non linear VIBRATION GATE calculation model
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Peculiar Nonlinear Depletion in Double-Layered Gated Si-δ-Doped GaAs
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作者 卢铁城 林理彬 +2 位作者 M.LEVIN V.GINODMAN I.SHLIMAK 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第5期538-542,共5页
The low-temperature measurement of Hall effect of the two-dimensional electron system in a double-layered gated Si-δ-doped GaAs is presented.A complex peculiar nonlinear dependence of the depletion on gate voltage i... The low-temperature measurement of Hall effect of the two-dimensional electron system in a double-layered gated Si-δ-doped GaAs is presented.A complex peculiar nonlinear dependence of the depletion on gate voltage is observed.The nonlinearity is also explained on the basis of the assumption that the double-capacity model consists of two δ-doped two-dimensional electron layers and a metallic gate,and the experimental result that the electron mobility is linear with the electron density on a log-log scale. 展开更多
关键词 nonlinear depletion double layerd gated Si-δ-doped GaAs
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Synchronization of a Class of Delayed Neural Networks with Sector Nonlinearity 被引量:3
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作者 HUANG You-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期124-131,共8页
In this paper, global synchronization is discussed for a general class of delayed neural networks with time-varying and distributed delays. Furthermore, the activation func- tions in the neural networks can be differe... In this paper, global synchronization is discussed for a general class of delayed neural networks with time-varying and distributed delays. Furthermore, the activation func- tions in the neural networks can be different type. Based on the drive-response concept and the Lyapunov stability theorem, some sufficient criteria are obtained to guarantee the global synchronization of the considered models even when input sector nonlinearity caused by physical limitations is presented in response systems. Finally, a typical example is also given to illustrate the effectiveness of the proposed synchronization scheme. 展开更多
关键词 SYNCHRONIZATION neural networks distributed delays sector nonlinearity
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Allowable Generalized Quantum Gates Using Nonlinear Quantum Optics
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作者 李春燕 李俊林 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期75-77,共3页
In this paper, we give an efficient physical realization of a double-slit duality quantum gate. Weak cross- Kerr nonlinearity is exploited here. The probability of success can reach 1/2. Asymmetrical slit duality cont... In this paper, we give an efficient physical realization of a double-slit duality quantum gate. Weak cross- Kerr nonlinearity is exploited here. The probability of success can reach 1/2. Asymmetrical slit duality control gate also can be constructed conveniently. The special quantum control gate could be realized easily in optical system by our current experimental technology. 展开更多
关键词 duality quantum computer quantum control gate weak cross-Kerr nonlinearity
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Quantitative Assessment of Hepatic Fibrosis by Contrast-enhanced Ultrasonography 被引量:2
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作者 Ming-bo Zhang En-ze Qux +2 位作者 En-ze Qu Ji-Bin Liu Jin-rui Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第4期208-215,共8页
Objective To explore the contrast-enhanced ultrasonographic features for quantitative assessment of hepatic fibrosis. Methods 86 patients with chronic viral hepatitis B were enrolled in this study from March 2007 to A... Objective To explore the contrast-enhanced ultrasonographic features for quantitative assessment of hepatic fibrosis. Methods 86 patients with chronic viral hepatitis B were enrolled in this study from March 2007 to August 2009. The patients were classified into 5 groups (S0-S4) according to fibrosis stage evaluated with ultrasound guided liver biopsy. New contrast-enhanced ultrasonography (CEUS) features including area under the time-intensity curve (TIC) of portal venous phase/hepatic arterial phase (Qp/Qa) and intensity of portal venous phase/hepatic arterial phase (Ip/Ia) were used to detect the blood supply ratio (portal vein/hepatic artery) in each group. Arrival time of portal vein trunk (Tp) and decreasing rate of TIC (β ) were also analyzed. Results Qp/Qa and Ip/Ia decreased from S0 to S4, while Tp and β increased. These 4 features were significantly correlated with the degree of fibrosis (P<0.001) and were significantly different among the five groups (P<0.001). Sensitivity and specificity of Ip/Ia were 80% and 86% for groups ≥S1, 75% and 86% for groups ≥ S2, 71% and 84% for groups ≥ S3, and 76% and 80% for group S4, respectively. Sensitivity and specificity of Qp/Qa were 70% and 88% for groups ≥ S1, 80% and 76% for groups ≥ S2, 74% and 70% for groups ≥ S3, and 81% and 95% for group S4, respectively. Conclusion Ip/Ia and Qp/Qa could be adopted as reliable, non-invasive features for quantitative assessment of hepatic fibrosis. 展开更多
关键词 hepatic fibrosis contrast-enhanced ultrasonography QUANTITATIVE non- invasive
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Nonlinear Finite Element Analysis of the Structure of Door Seals
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作者 赵建才 朱训生 周持兴 《Journal of Donghua University(English Edition)》 EI CAS 2005年第2期62-65,共4页
In order to evaluate the influence of the seal structure on door dosing force, nonlinear finite dement methed is introduced to analyze compression deformation of a door seal for SANTANA (name of the car made by Shang... In order to evaluate the influence of the seal structure on door dosing force, nonlinear finite dement methed is introduced to analyze compression deformation of a door seal for SANTANA (name of the car made by Shanghai Volkswagen Co. Ltd). MSC. Marc software is used to analyze the large deformation of the seal and the compression test is done to prove the computational results. The results show that the compression loads of the door seal are larger than the standard value of Shanghai Volkswagen Co. Ltd and the seal structure needs to be optimized. There are consistent relationships between calculating results and experimental results and the simulation method is effective. 展开更多
关键词 Nonlinear finite element STRUCTURE Door seal Compression load
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Infrared Radiation Temperature Comparison on Body Surface of Points Between Healthy People and Patients with Hyperplasia of Mammary Glands 被引量:15
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作者 李恒 应荐 +6 位作者 沈雪勇 金明子 赵玲 胡升芳 孙霃平 王丽祯 韩丑萍(翻译) 《Journal of Acupuncture and Tuina Science》 2008年第4期215-218,共4页
Objective: To compare the difference of infrared radiation temperature on body surface of points between healthy people and patients with hyperplasia of mammary glands. Method: The thermaCATMT P30 infrared thermal i... Objective: To compare the difference of infrared radiation temperature on body surface of points between healthy people and patients with hyperplasia of mammary glands. Method: The thermaCATMT P30 infrared thermal imaging system was selected to measure the infrared radiation temperature on body surface of eight points in four meridians in 74 patients with hyperplasia of mammary glands and 63 healthy people. Results: The infrared radiation temperatures on body surface of right Youmen (KI 21) in cases with hyperplasia of mammary glands were significantly higher than the healthy people (P=-0.009), and the infrared radiation temperatures on left Youmen (KI 21) and other points had no significant difference with healthy people (P〉0.05). Conclusion: The infrared radiation temperatures on body surface of right Youmen (KI 21) have significant differences with healthy people. This might occur because of the pathogenesis of hyperplasia of mammary glands and of the specificity of the point Youmen (KI 21). 展开更多
关键词 Fibrocystic Breast Disease Infrared Rays RADIATION Acupoint Youmen (KI 21) Skin Temperature
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