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1.
CMOS门电路的功率与数据相关性   总被引:1,自引:0,他引:1  
为了研究电路实现形式对密码芯片抗“功耗分析攻击”能力的影响,考察了CMOS门电路的交流馈通对电源电流的影响,输入组合对电路充放电网络的影响以及静态电流的数据相关性。对静态逻辑、N/P型动态逻辑和差分Domi-no逻辑的这3种信息泄漏机制进行了具体分析,并对这4种逻辑的2输入与门和或门进行了仿真。静态电路和普通动态电路不同输入变化对应的电流曲线间的最大差值都大于60μA,而差分Domino电路的所有电流曲线之差小于2μA。结果表明:采用N型Domino逻辑,并使数据输入只在时钟为高时有效,相对于其他逻辑功耗信息泄漏要小。  相似文献   

2.
针对实数编码遗传算法中的算术杂交算子是否存在问题相关性进行了实验研究.首先,用几种常用的算术杂交算子对测试函数进行优化实验,结果表明,选用何种算术杂交算子算法更有效与具体优化问题有关,即算术杂交算子存在问题相关性,且它随变异概率的变化而呈现比较复杂的变化.其次,提出了根据算术杂交算子在无变异时的优化效果以及有变异时与变...  相似文献   

3.
股票市场开盘收益率在一定程度上反映了投资者对当日市场收益率的预期,而收盘收益率是当日收益率的实现值。在去除趋势性因素的影响后,完全有效市场下这两种收益率之间不应该具有显著的相关性。对2015年中国A股市场这两种收益率相关性的实证研究发现,在去除趋势性变化后,两者之间仍存在显著的正相关性,这说明中国A股市场的有效性还不够,可能有部分投资者能够掌握额外信息,从而能对市场走势进行准确预测。  相似文献   

4.
Most continuous antigenic determinants of tobacco mosaic virus protein (TMVP), myoglobin and lysozyme correspond to those surface regions in the protein structure, as determined by X-ray crystallography, which possess a run of high-temperature factors along the polypeptide backbone, that is, a high segmental mobility. The mobility of an antigenic determinant may make it easier to adjust to a pre-existing antibody site not fashioned to fit the exact geometry of a protein. The correlation found between temperature factors and antigenicity is better than that between hydrophilicity and antigenicity.  相似文献   

5.
本文讨论了回归分析中当自变量间存在很强的线性相关关系时,如何合理地选择自变量,以及如何进行自变量间的相对相关性程度分析等问题。  相似文献   

6.
传统的认识论意义观认为作品的意义即作者在作品中寄托的原义;迦达默尔则认为作品的意义不是先于理解而有的东西,在解释者的理解之前总是处于未定状态,向多种解释开放。本文认为作者在作品中有明示或暗示的作品,意义是确定的,即以作者的原意为意义;对没有任何暗示的作品,其意义才是开放的。  相似文献   

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2009年金融危机给国际贸易带来了巨大的冲击,作为中国战略伙伴的俄罗斯在此次金融危机后也陷入了严重的负增长,中俄边境贸易受到了严重的冲击。文章通过TCD和TSC分析,并以满洲里边境口岸为实例,探讨中俄边境贸易的现状和未来。  相似文献   

9.
A functional correlate for the dihydropyridine binding site in rat brain   总被引:11,自引:0,他引:11  
D N Middlemiss  M Spedding 《Nature》1985,314(6006):94-96
Calcium channels, controlling the influx of extracellular Ca2+ and hence neurotransmitter release, exist in the brain. However, drugs classed as calcium antagonists and which inhibit Ca2+ entry through voltage-activated Ca2+ channels in heart and smooth muscle, seem not to affect any aspect of neuronal function in the brain at pharmacologically relevant concentrations. Yet the dihydropyridine calcium antagonists (for example, nitrendipine) bind stereospecifically with high affinity to a recognition site on brain-cell membranes thought to represent the Ca2+ channel and consequently, the physiological relevance of these sites has been questioned. However, activation of voltage-dependent Ca2+ channels can increase cytoplasmic Ca2+ and neurotransmitter release in neuronal tissue. We show here that Bay K8644, a dihydropyridine Ca2+-channel activator, can augment K+-stimulated release of serotonin from rat frontal cortex slices and that these effects can be antagonized by low concentrations of calcium antagonists. As 3H-dihydropyridine binding to cortical membrane preparations resembles the binding in heart and smooth muscle where there are good functional correlates we conclude that the dihydropyridine binding sites in the brain represent functional Ca2+ channels that can be unmasked under certain circumstances.  相似文献   

10.
相关分析是描述两个或两个以上变量间关系密切程度的统计方法.本文主要讨论随机向量间的相关性,重点地讨论了总体简单相关系数、复相关系数和典型相关系数的计算过程,以及广义相关系数与上三者之间的关系.  相似文献   

11.
脑脊液铁离子含量与急性颅脑损伤脑水肿关系的研究   总被引:1,自引:0,他引:1  
观察急性颅脑损伤后脑脊液中铁离子含量,探讨铁离子含量与脑水肿之间的关系。应用亚铁嗪法测定脑脊液中铁离子含量,并对脑脊液中铁离子含量与脑压、脑脊液中红细胞含量之间的关系进行分析。分析结果表明,实验组脑脊液中铁离子含量显著增加(P<0.001),且铁离子含量与脑压明显相关,与脑脊液中红细胞含量无明显相关。  相似文献   

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目的:评估超重与血脂异常及其相互关系,指导超重与血脂异常防治。方法:调查大理市在职和离、退休干部职工3 870人,测量身高和体重,计算相应的BMI;检测空腹血清总胆固醇和甘油三酯;按性别、BMI分组,统计各组血脂异常(高TC血症、高TG血症)患病率。结果:高TC血症、高TG血症患病率在BMI≥24组分别为11.75%和37.20%,与BMI〈24组(6.14%和14.73%)比较,超重组患病率分别是非超重组的1.91倍和2.53倍,差异具有统计学意义。结论:超重者血脂异常患病率较高,是血脂异常监测和防治的重点人群。  相似文献   

15.
A formulated as △fH m (PPDs,g)=a+ΣbiPi + cifi is put forward for estimating standard formation enthalpies of pyridine-derivatives (PDDs), in which,P i is path index andc i f i is an amended term of interaction between substituent and N atom on pyridine ring. The Calculations based on the model were carried out for some pyridine-derivatives. The values of standard formation enthalpy calculated are consistent with those in literature. Foundation item: Supported by the National Natural Science Foundation of China (29971024) Biography: LI Liang-chao (1958-), male, Associate professor, Research direction: calculating chemistry.  相似文献   

16.
R Raisman  M Briley  S Z Langer 《Nature》1979,281(5727):148-150
The discovery of high-affinity binding sites for psychoactive drugs such as benzodiazepines, opiates and neuroleptics has opened up new approaches to the study of these drugs and their mechanisms of action. Although most tricyclic antidepressants inhibit neuronal uptake of noradrenaline and serotonin, their mechanism of action remains unclear. Changes in the sensitivity of the beta-receptor after chronic tricyclic antidepressant treatment suggest that they modulate noradrenergic neurotransmission. Tricyclic antidepressants also act directly on cholinergic, histaminergic, alpha-adrenergic and serotonergic receptors. It is not clear, however, which, if any, of these effects are related to the primary antidepressant effect or whether they are simply responsible for some of the side effects. We have thus investigated the possibility that specific binding sites for tricyclic antidepressants exist in the central nervous system. So far, binding studies using 3H-labelled tricyclic antidepressant drugs have only detected binding to histaminergic H2 and cholinergic muscarinic receptors and low-affinity binding. We demonstrate here a population of specific high-affinity binding sites for 3H-imipramine on brain membranes which may be responsible for the antidepressant effects of these drugs.  相似文献   

17.
在城市建设与发展进程中,加强城市文化建设已经成为其重要组成部分之一,而与城市文化建设直接相关的一个方面就是发挥高校图书馆的文化传播作用。阐述了城市建设的关键因素,分析了高校图书馆对提升城市建设的价值,提出了高校图书馆推动城市建设进程的建议。  相似文献   

18.
利用Black-Scholes期权定价的方法,给出了沪深两地上市初期权证及其标的股票的收益率和波动率,并对波动率数据进行回归分析;数值分析结果表明:多数权证的波动率和其标的资产的波动率没有线性相关性,数据经Box-Cox变换后分析,结论成立;这表明在权证上市初期,多数权证的波动率和标的资产波动率没有线性相关性,权证价格涨跌幅度大,严重偏离其市场价格;投资权证更多的是利用了其投机功能,其套期保值和风险管理功能被忽略.  相似文献   

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经营者薪酬与企业绩效相关性问题的研究是构建科学合理的经营者薪酬制度的理论依据.以制造业国有企业2005~2007年数据为样本,对我国上市公司经营者薪酬与企业绩效相关性进行实证研究.运用多元回归分析方法,引入年度虚拟变量,构建企业规模、地区为控制变量的经营者薪酬与企业绩效回归分析模型.研究表明:制造业国有企业经营者薪酬与企业绩效存在正相关关系,年度虚拟变量与经营者薪酬指标无显著相关关系,大型企业的经营者薪酬对企业绩效有显著性影响,经营者薪酬与企业绩效的相关性与企业所在地区的经济发达程度正相关.  相似文献   

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