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Capacitive Model and S-Parameters of Double-Pole Four-Throw Double-Gate RF CMOS Switch
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作者 Viranjay M. Srivastava Kalyan S. Yadav Ghanashyam Singh 《Wireless Engineering and Technology》 2011年第1期15-22,共8页
In this paper, we have analyzed the Double-Pole Four-Throw Double-Gate Radio-Frequency Complementary Metal-Oxide-Semiconductor (DP4T DG RF CMOS) switch using S-parameters for 1 GHz to 60 GHz of frequency range. DP4T D... In this paper, we have analyzed the Double-Pole Four-Throw Double-Gate Radio-Frequency Complementary Metal-Oxide-Semiconductor (DP4T DG RF CMOS) switch using S-parameters for 1 GHz to 60 GHz of frequency range. DP4T DG RF CMOS switch for operation at high frequency is also analyzed with its capacitive model. The re-sults for the development of this proposed switch include the basics of the circuit elements in terms of capacitance, re-sistance, impedance, admittance, series equivalent and parallel equivalent of this network at different frequencies which are present in this switch whatever they are ON or OFF. 展开更多
关键词 Capacitive model double-GATE MOsFET DP4T sWITCH Isolation Radio Frequency RF sWITCH s-PARAMETER and VLsI
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Quantification of Ride Comfort Using Musculoskeletal Mathematical Model Considering Vehicle Behavior
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作者 Junya Tanehashi Szuchi Chang +4 位作者 Takahiro Hirosei Masaki Izawa Aman Goyal Ayumi Takahashi Kazuhito Misaji 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2287-2306,共20页
This research aims to quantify driver ride comfort due to changes in damper characteristics between comfort mode and sport mode,considering the vehicle’s inertial behavior.The comfort of riding in an automobile has b... This research aims to quantify driver ride comfort due to changes in damper characteristics between comfort mode and sport mode,considering the vehicle’s inertial behavior.The comfort of riding in an automobile has been evaluated in recent years on the basis of a subjective sensory evaluation given by the driver.However,reflecting driving sensations in design work to improve ride comfort is abstract in nature and difficult to express theoretically.Therefore,we evaluated the human body’s effects while driving scientifically by quantifying the driver’s behavior while operating the steering wheel and the behavior of the automobile while in motion using physical quantities.To this end,we collected driver and vehicle data using amotion capture system and vehicle CAN and IMU sensors.We also constructed a three-dimensional musculoskeletal mathematical model to simulate driver movements and calculate the power and amount of energy per unit of time used for driving the joints and muscles of the human body.Here,we used comfort mode and sport mode to compare damper characteristics in terms of hardness.In comfort mode,damper characteristics are soft and steering stability is mild,but vibration from the road is not easily transmitted to the driver making for a lighter load on the driver.In sport mode,on the other hand,damper characteristics are hard and steering stability is comparatively better.Still,vibration from the road is easily transmitted to the driver,whichmakes it easy for a load to be placed on the driver.As a result of this comparison,it was found that a load was most likely to be applied to the driver’s neck.This result in relation to the neck joint can therefore be treated as an objective measure for quantifying ride comfort. 展开更多
关键词 Human engineering BIOMECHANICs driver’s sense of fatigue double lane change musculoskeletal mathematical model
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Effects of natural-cerebrolysin-containing serum on neurotoxicity and synaptogenesis in amyloid-beta 1-40-induced Alzheimer's disease in vitro models 被引量:1
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作者 Yinghong Li Zhengzhi Wu +3 位作者 Andrew C. J. HuangO Ming Li XiaoLi Zhang Jiguo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期85-91,共7页
BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, an... BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression. 展开更多
关键词 natural-cerebrolysin Alzheimer's disease in vitro model NEUROTOXICITY neuroprotective effect amyloid beta protein 1-40
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基于T-S模型的倒立摆双闭环串级模糊控制设计与仿真 被引量:15
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作者 侯涛 董海鹰 《系统仿真学报》 EI CAS CSCD 北大核心 2007年第11期2477-2479,2526,共4页
针对具有多变量、非线性特性的倒立摆系统,提出了一种基于T-S模型的双闭环串级模糊控制方法。在该方法中,内环控制倒立摆的角度,外环控制倒立摆小车的位移,并对双闭环参数耦合实现了解耦,降低了系统设计的难度和复杂度。数字仿真结果表... 针对具有多变量、非线性特性的倒立摆系统,提出了一种基于T-S模型的双闭环串级模糊控制方法。在该方法中,内环控制倒立摆的角度,外环控制倒立摆小车的位移,并对双闭环参数耦合实现了解耦,降低了系统设计的难度和复杂度。数字仿真结果表明了该方法的可行性。 展开更多
关键词 倒立摆 双闭环解耦 串级模糊控制 T-s模型
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山西霍山山前断裂冲沟S-A双对数图、凹曲指数与陡峭指数的构造响应特征 被引量:5
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作者 毕丽思 何宏林 +3 位作者 徐岳仁 魏占玉 石峰 孙浩越 《地震地质》 EI CSCD 北大核心 2017年第6期1158-1172,共15页
利用能够反映构造隆升作用与河流下切侵蚀作用之间关系的河流水力侵蚀模型,以小流域性的霍山山前断裂为实验区,基于高分辨率DEM数据,分析了64条横跨断裂发育的冲沟的S-A双对数图、凹曲指数(θ)与陡峭指数(logks);研究了它们对霍山山前... 利用能够反映构造隆升作用与河流下切侵蚀作用之间关系的河流水力侵蚀模型,以小流域性的霍山山前断裂为实验区,基于高分辨率DEM数据,分析了64条横跨断裂发育的冲沟的S-A双对数图、凹曲指数(θ)与陡峭指数(logks);研究了它们对霍山山前断裂构造活动的响应特征:1)冲沟的S-A双对数图基本都呈现出明显的上凸特征,这是对断裂区域构造隆升速率大于河流下切侵蚀速率的直观响应;2)冲沟的凹曲指数θ值均<0.35,平均值仅为0.223,远低于均衡河道的经验平均值(0.49),这是冲沟纵剖面下凹程度低的直接的量化表达,反映了冲沟的发育是很年轻的,而其原因主要是霍山山前断裂频繁而强烈的构造运动使冲沟没有足够的时间通过下切侵蚀作用来调整剖面形态;3)冲沟的陡峭指数logks值呈现出老爷顶一带最高,南北两侧较低,而且北部比南部高的分布特征;这在一定程度上指示了霍山山前断裂在老爷顶一带隆升速率最大,南北两侧较低,而且北部隆升速率比南部高。 展开更多
关键词 霍山山前断裂 河流水力侵蚀模型 冲沟 DEM s-A双对数图 凹曲指数 陡峭指数 构造响应
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THPFSY-2型双容水箱液位实验系统鲁棒故障诊断 被引量:2
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作者 陈虹丽 李强 刘纹岩 《实验室研究与探索》 CAS 北大核心 2017年第11期44-47,63,共5页
研究了THPFSY-2型双容水箱在干扰和故障作用下的鲁棒故障诊断问题。首先根据双容水箱机理模型建立双容水箱的T-S模糊模型,然后通过引入参考模型,建立有关故障残差估计误差的广义残差方程,将基于T-S模型的故障诊断滤波器设计问题转换成... 研究了THPFSY-2型双容水箱在干扰和故障作用下的鲁棒故障诊断问题。首先根据双容水箱机理模型建立双容水箱的T-S模糊模型,然后通过引入参考模型,建立有关故障残差估计误差的广义残差方程,将基于T-S模型的故障诊断滤波器设计问题转换成了典型的系统鲁棒控制问题。根据有界实引理给出了参数最优解的线性矩阵不等式解的形式,并对其正确性进行了证明。通过仿真验证了该算法在双容水箱故障诊断中的有效性。 展开更多
关键词 双容水箱 T—s模型 鲁棒故障诊断 线性矩阵不等式
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基于S-函数的无刷直流电机双闭环速度控制系统仿真 被引量:3
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作者 解后循 高翔 +1 位作者 赵世婧 卢慧娟 《拖拉机与农用运输车》 2009年第1期52-55,共4页
在分析无刷直流电机(BLDCM)数学模型及相关文献的基础上,采用S-函数对三相绕组梯形反电势、绕组端电压、星形连接中性点电压及电流反馈采集过程等难点进行建模;采用转速、电流双反馈对无刷直流电机调速系统进行建模。仿真与试验数据的... 在分析无刷直流电机(BLDCM)数学模型及相关文献的基础上,采用S-函数对三相绕组梯形反电势、绕组端电压、星形连接中性点电压及电流反馈采集过程等难点进行建模;采用转速、电流双反馈对无刷直流电机调速系统进行建模。仿真与试验数据的对比分析证明了该方法的有效性。该方法提高了仿真计算效率,较准确实现了对实际三相PWM端电压及由于换向造成的电枢电流动态变化的模拟。该建模方法已被用于对汽车电动液压助力转向系统的研究。 展开更多
关键词 电动液压助力转向 无刷直流电机 仿真建模 s-函数 双闭环系统
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基于T-S模型的双时变时滞不确定系统的鲁棒H_∞容错控制
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作者 邵克勇 张晓花 +1 位作者 李鑫 陈峤郴 《计算机应用研究》 CSCD 北大核心 2013年第5期1393-1396,共4页
为了解决系统在含有执行器局部或者完全失效故障情况下的鲁棒H∞容错控制问题,针对一类状态和控制输入同时存在时变时滞的不确定非线性系统,采用T-S模糊模型来描述,利用并行分布补偿(PDC)算法设计了模糊状态反馈控制器,结合Lyapunov稳... 为了解决系统在含有执行器局部或者完全失效故障情况下的鲁棒H∞容错控制问题,针对一类状态和控制输入同时存在时变时滞的不确定非线性系统,采用T-S模糊模型来描述,利用并行分布补偿(PDC)算法设计了模糊状态反馈控制器,结合Lyapunov稳定性理论给出了保证该模糊容错控制系统渐近稳定的充分条件,不但保证了系统输出的鲁棒稳定性,而且能够满足给定的鲁棒H∞性能指标。最后通过MATLAB仿真对比系统中有外部干扰和无外部干扰情况下的系统输出曲线,验证了所提出方法的可行性。 展开更多
关键词 鲁棒 容错 T—s模型 模糊控制器 双时变时滞 非线性系统
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基于T-S模糊加权的风电机组变桨距的双模切换优化控制 被引量:2
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作者 张强 侯涛 《电机与控制应用》 2018年第7期122-126,共5页
传统的PID变桨距控制策略存在转速波动较大、变桨的跟随性差等不足。以风速在额定风速以上时,使风力发电机的输出功率稳定在额定功率为研究目标。针对变桨系统的惯性与延迟导致控制过程动态调节时间长、超调量大等问题,提出了基于T-S模... 传统的PID变桨距控制策略存在转速波动较大、变桨的跟随性差等不足。以风速在额定风速以上时,使风力发电机的输出功率稳定在额定功率为研究目标。针对变桨系统的惯性与延迟导致控制过程动态调节时间长、超调量大等问题,提出了基于T-S模糊加权的模糊与PID双模切换优化变桨距控制策略。以Simulink为试验平台,搭建了永磁直驱风力发电机组的变桨控制模型。通过仿真验证表明,所提方法具有模糊控制与PID控制两者的优点,控制输出的桨距角精度更高、响应速度更快、功率更加靠近发电机输出的额定功率。 展开更多
关键词 风力发电 变桨 T-s模糊加权 双模控制
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The relationship between international crude oil prices and China's refined oil prices based on a structural VAR model 被引量:4
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作者 Song Han Bao-Sheng Zhang +1 位作者 Xu Tang Ke-Qiang Guo 《Petroleum Science》 SCIE CAS CSCD 2017年第1期228-235,共8页
With the frequent fluctuations of international crude oil prices and China's increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domesti... With the frequent fluctuations of international crude oil prices and China's increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domestic refined oil price. This paper aims to investigate the transmission and feedback mechanism between international crude oil prices and China's refined oil prices for the time span from January 2011 to November 2015 by using the Granger causality test, vector autoregression model, impulse response function and variance decomposition methods. It is demonstrated that variation of international crude oil prices can cause China domestic refined oil price to change with a weak feedback effect. Moreover, international crude oil prices and China domestic refined oil prices are affected by their lag terms in positive and negative directions in different degrees. Besides, an international crude oil price shock has a signif- icant positive impact on domestic refined oil prices while the impulse response of the international crude oil price variable to the domestic refined oil price shock is negatively insignificant. Furthermore, international crude oil prices and domestic refined oil prices have strong historical inheri- tance. According to the variance decomposition analysis, the international crude oil price is significantly affected by its own disturbance influence, and a domestic refined oil price shock has a slight impact on international crude oil price changes. The domestic refined oil price variance is mainly caused by international crude oil price disturbance, while the domestic refined oil price is slightly affected by its own disturbance. Generally, domestic refined oil prices do not immediately respond to an international crude oil price change, that is, there is a time lag. 展开更多
关键词 International crude oil prices China's refinedoil prices VAR model Granger causality - Impulseresponse Variance decomposition
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Modeling of Unsteady Flow through Junction in Rectangular Channels: Impact of Model Junction in the Downstream Channel Hydrograph 被引量:2
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作者 Seidou Kane Soussou Sambou +5 位作者 Issa Leye Raymond Diedhiou Seni Tamba Mouhamed Talla Cisse Didier Maria Ndione Mousse Landing Sane 《Computational Water, Energy, and Environmental Engineering》 2017年第3期304-319,共16页
Open channel junctions are encountered in urban water treatment plants, irrigation and drainage canals, and natural river systems. Junctions are very important in municipal sewerage systems and river engineering. Adeq... Open channel junctions are encountered in urban water treatment plants, irrigation and drainage canals, and natural river systems. Junctions are very important in municipal sewerage systems and river engineering. Adequate theoretical description of flow through an open channel junction is difficult because numerous variables are to be considered. Equations of junction models are based on mass and momentum or mass and energy conservation. The objective of this study is to compare two junction models for subcritical flows. In channel branches, we solve numerically the Saint-Venant hyperbolic system by combining Preissmann scheme and double sweep method. We validate our results with HEC-RAS using Nash and Sutcliffe efficiency. In junction models, equality of water stage and complete energy conservation equation from HEC-RAS are compared. Outcome of the research clearly indicates that the complete conservation energy model is more suitable in flow through junction than equality of water stage model in serious situations. 展开更多
关键词 JUNCTION model HEC RAs saint-Venant’s Equations double sWEEP Method EQUALITY of Water sTAGEs Energy Conservation modelling of Flow
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Development of a Zebrafish Model for Rapid Drug Screening against Alzheimer's Disease 被引量:3
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作者 Wenhai Huang Chuansheng Li +3 位作者 Zhengrong Shen Xiaoyu Zhu Bo Xia Chunqi Li 《Journal of Pharmacy and Pharmacology》 2016年第4期162-173,共12页
Alzheimer's disease, the leading cause of dementia in the elderly, is a complex neurodegenerative disorder which leads to a progressive decline in cognitive functions. A rapid screening model is highly demanded for i... Alzheimer's disease, the leading cause of dementia in the elderly, is a complex neurodegenerative disorder which leads to a progressive decline in cognitive functions. A rapid screening model is highly demanded for identification and evaluation of novel anti-Alzheimer's disease drugs from a large numbers of compounds. Until now, numerous studies utilized zebrafish model for drug discovery. Since aluminum can induce a similar biological activity in zebrafish as in Alzheimer patients, in this study, we developed a novel animal model using 3 to 5 day post-fertilization larval zebrafish by optimizing the doses and duration of aluminum chloride exposure. Six anti-Alzheimer's disease drugs with a variety of mechanisms were tested to validate the newly developed zebrafish model. Importantly, Rivastigmine, ThT, Flurbiprofen and AM-117 could increase the value of Dyskinesia Recovery Rate by 53.4-64%, 169.4-200%, 54.5-96% and 70.9-121%, respectively. Rivastigmine, Memantine, ThT, Flurbiprofen, Rosiglitazone and AM-117 improved the value of Response Efficiency by 86.6-175.1%, 28.2-66.6%, 127.2-236.5%, 118.3-323.7%, 26.6-140.8% and 70.2-161.4%, respectively. Our results suggest that the zebrafish model developed in this study could be a useful tool for high throughput screening of potential novel anti-Alzheimer's disease leading compounds targeting acetylcholinesterase, N-methyl-D-aspartic acid receptor, γ-secretase, peroxisome proliferator-activated receptor-γand amyloid-β. 展开更多
关键词 Alzheimer's disease 3-5dpf Larvae screening platform zebrafish model.
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基于T-S模型的二级倒立摆模糊控制研究
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作者 史晓霞 《北京建筑工程学院学报》 2009年第1期34-37,共4页
对非线性、强耦合和绝对不稳定的二级倒立摆进行了运动分析,并针对实验用的二级倒立摆,建立了其运动的状态方程.根据实验中运动的特点,提出了基于T-S模型的模糊控制,取得了较好的控制效果.
关键词 二级倒立摆 状态方程 T-s模型 模糊控制
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Question of Parity Non-conservation in Weak Interactions
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作者 Zuodong Sun 《Journal of Physical Science and Application》 2021年第2期33-49,共17页
In order to reasonably explain the phenomenon of cell bioelectricity,we proposed the conservation law of cell membrane area,established the ion inequality equation,and therefore paid attention to the mystery of“θ-τ... In order to reasonably explain the phenomenon of cell bioelectricity,we proposed the conservation law of cell membrane area,established the ion inequality equation,and therefore paid attention to the mystery of“θ-τ”.We researched and analyzed the“θ-τ”mystery,discussed the parity non-conservation in weak interactions,suggested possible experiments to test the parity non-conservation in weak interactions,and gave our research and analysis conclusions:The parity non-conservation in weak interactions,is still a“conjecture”;The experimental scheme suggested in the papers by C.N.Yang et al.cannot determine whether the weak interaction can separate left and right,and it is impossible to directly answer whetherθandτin the“θ-τ”mystery are the same particle;The Co60βdecay experiment such as C.S.Wu is a pseudo-mirror experiment,whether the experimental result violates parity conservation is only based on the assumption of C.N.Yang et al.In fact,experiments such as polarized Co60 did not overturn the so-called“law of parity conservation”.The mirror image principle does not have any physical meaning,does not correspond to any physical conservation quantity,and cannot be destroyed by any physical experiment.In the process of turning“mirror symmetry”and“mirror asymmetry”into so-called physical“common sense”and scientific“facts”respectively,the methods of transformation are“stealing concepts”and“circular argumentation”.The“θ-τ”mystery is a“man-made”mystery.θandτare two different particles,which may be the result of the same precursor particle being divided into two.The work of C.N.Yang,T.D.Lee,C.S.Wu et al.has brought quantum physicists from the“small black room”to the“bigger black room”or“smaller black room”.The right and wise choice is to go back through the door that came in.With the development of science today,it is time for some contents to reform from the bottom. 展开更多
关键词 Mystery ofθ-τ question of parity non-conservation C.N.Yang T.D.Lee C.s.Wu “origami windmill”model.
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双S曲线模型:对倒U型理论的发展与完善 被引量:10
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作者 饶会林 陈福军 董藩 《北京师范大学学报(社会科学版)》 CSSCI 北大核心 2005年第3期123-129,共7页
J·G·威廉姆逊关于区域经济差距走势的倒U字型观点是正确的,但由于其方法的不完善,引起了争论。发展这个理论,必须引入双S曲线模型,它能清晰地全面地反映和回答两区域差距形成的主要原因、机制和变化趋势,准确指导区域间协调发... J·G·威廉姆逊关于区域经济差距走势的倒U字型观点是正确的,但由于其方法的不完善,引起了争论。发展这个理论,必须引入双S曲线模型,它能清晰地全面地反映和回答两区域差距形成的主要原因、机制和变化趋势,准确指导区域间协调发展,把倒U字型观点建立在科学基础之上。 展开更多
关键词 曲线模型 U型 区域经济差距 区域差距 变化趋势 协调发展 科学基础 区域间 字型 走势
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S弯扩压器中四种湍流模型的比较 被引量:6
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作者 张丽芬 刘振侠 吕亚国 《航空动力学报》 EI CAS CSCD 北大核心 2008年第10期1888-1891,共4页
采用Realizableκ-ε,S-A(Spalart-Allmaras),SST(Shear stress transport剪切应力输运),RSM(Reynolds stress equation model雷诺应力模型)四种湍流模型对S弯扩压器内的分离流动进行了模拟,分析了不同湍流模型对计算结果的影响.将不同... 采用Realizableκ-ε,S-A(Spalart-Allmaras),SST(Shear stress transport剪切应力输运),RSM(Reynolds stress equation model雷诺应力模型)四种湍流模型对S弯扩压器内的分离流动进行了模拟,分析了不同湍流模型对计算结果的影响.将不同轴向位置的表面压力系数、分离区的大小、马赫数等三个量的实验值与计算值进行了比较,结果表明:分离区湍流模型对表面压力分布影响较大,未分离区不同湍流模型模拟精度相当;S-A模型对分离区的模拟较保守,RSM模型对分离的模拟精度较高,SST与RSM模拟结果很接近;各湍流模型计算的高速区域均比实验值大.扩压器的平均总压恢复系数受湍流模型影响不大,和实验结果吻合较好. 展开更多
关键词 湍流模型 s弯扩压器 Realizable κ-ε s-A(spalart-Allmaras) ssT(shear stress transport剪切应力输送) RsM(Reynolds stressequation model雷诺应力模型)
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基于双S模型的战略性新兴产业集群供应链知识创新过程与路径研究——以CS新材料产业集群为例 被引量:3
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作者 吉敏 胡汉辉 +1 位作者 陈金丹 谢庆红 《科技进步与对策》 CSSCI 北大核心 2013年第12期71-77,共7页
基于集群供应链企业知识创新过程特征,从供应链企业横向合作、纵向本链合作、纵向跨链合作视角,研究了战略性新兴产业集群供应链知识创新过程与路径。在此基础上,基于SECI知识螺旋,建立了集群供应链知识创新双S模型。最后,以新材料产业... 基于集群供应链企业知识创新过程特征,从供应链企业横向合作、纵向本链合作、纵向跨链合作视角,研究了战略性新兴产业集群供应链知识创新过程与路径。在此基础上,基于SECI知识螺旋,建立了集群供应链知识创新双S模型。最后,以新材料产业集群为例,分析了这一战略性新兴产业集群供应链知识创新过程和传导路径。 展开更多
关键词 s模型 战略性新兴产业 集群供应链 知识创新过程 知识传导路径
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中药Ⅰ号方对APP/PS1双转基因模型小鼠APP代谢的影响 被引量:4
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作者 隋小龙 梁良 +8 位作者 张玲 朱华 徐艳峰 黄澜 徐玉环 韩云林 姚志刚 秦川 邓巍 《中国实验动物学报》 CAS CSCD 2014年第6期49-53,I0004,I0005,共7页
目的研究中药I号方对APP/PS1双转基因模型小鼠APP代谢的影响。方法将5月龄APP/PS1双转基因模型小鼠随机分为模型组(vehicle)、中药Ⅰ号方低剂量组(0.6 g/kg)、中剂量组(1.2 g/kg)和高剂量组(2.4 g/kg),并以同窝阴性小鼠作为正常对照组(w... 目的研究中药I号方对APP/PS1双转基因模型小鼠APP代谢的影响。方法将5月龄APP/PS1双转基因模型小鼠随机分为模型组(vehicle)、中药Ⅰ号方低剂量组(0.6 g/kg)、中剂量组(1.2 g/kg)和高剂量组(2.4 g/kg),并以同窝阴性小鼠作为正常对照组(wild-type,WT),每组16只,雌雄各半。给药小鼠每天灌胃一次,模型组和正常对照组分别给予等体积的双蒸水灌胃。给药四个月后,用免疫组化和Western blot检测淀粉样前体蛋白(APP)及其代谢产物和分解酶的变化。结果 Western blot结果显示,与模型组相比,治疗组低剂量、中剂量和高剂量给药组能显著降低APP分解酶(ADAM10和BACE1)(P<0.01)及APP的分解产物的量,如:β-CTF(C99)、α-CTF(C83)、s APPα、s APPβ(P<0.01)。结论中药I号方通过影响APP的分解过程减少淀粉样蛋白(β-amyloid peptide,Aβ)的生成,减少脑内老年斑的沉积。 展开更多
关键词 中药Ⅰ号方 阿尔茨海默病 APP分解酶 APP/Ps1双转基因AD模型小鼠
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基于双S模型的我国保险公司企业文化分析
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作者 祝向军 汪水山 《保险职业学院学报》 2008年第5期50-54,共5页
我国保险公司规模快速扩张,传统企业组织面临组织拆分的压力,企业文化成为凝聚企业的越来越重要的手段。保险企业主体迅速增加,也需要对不同类型保险公司企业文化进行分析和比较。本文运用双S模型分析了我国保险公司网络型、图利型、共... 我国保险公司规模快速扩张,传统企业组织面临组织拆分的压力,企业文化成为凝聚企业的越来越重要的手段。保险企业主体迅速增加,也需要对不同类型保险公司企业文化进行分析和比较。本文运用双S模型分析了我国保险公司网络型、图利型、共有型等不同类型的企业文化,并结合对我国保险公司企业文化的调查数据,进行典型案例分析。最后,对我国保险公司企业文化的选择和建设给出建议。 展开更多
关键词 s模型 保险公司 企业文化
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不对称倍压整流电路的S域分析
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作者 文继国 《四川轻化工学院学报》 2002年第2期53-56,共4页
利用倍压整流电路的S域模型设计一种算法,详细推导不对称倍压整流电路的充电过程,导出定量计算电容器电压的数学表达式,利用所得表达式对对称,非对称倍压整流电路进行讨论,绘出了电容器电压充电曲线,并证明达到倍压目的所经历的充电周... 利用倍压整流电路的S域模型设计一种算法,详细推导不对称倍压整流电路的充电过程,导出定量计算电容器电压的数学表达式,利用所得表达式对对称,非对称倍压整流电路进行讨论,绘出了电容器电压充电曲线,并证明达到倍压目的所经历的充电周期数。 展开更多
关键词 不对称倍压整流电路 电压跃变 初始值 s域模型 拉普拉斯变换 电容器 充电曲线
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