Preparedness and phobia: Effects of stimulus content on human visceral conditioning.

Conducted 6 experiments to test M. Seligman's (see PA, Vols 45:1675 and 48:1326) preparedness theory of phobia in human classical conditioning of skin conductance and heart rate responses with approximately 12 undergraduates. Conditioned stimuli (CSs) were photographs of plants, human artifacts, and phobia-relevant animals. Both aversive tactile and auditory unconditioned stimuli (UCSs) were assessed. Combined present results indicate that, consistent with results obtained by A. Ohman and colleagues in research conducted between 1975 and 1985 to test Seligman's theory, electrodermal extinction was slower to phobia-relevant stimuli than to other stimuli (and in the present study, was shown to depend on a tactile UCS); however, unlike the findings of Ohman and colleagues, when Ss were told that shocks would be discontinued, phobic CSs extinguished as readily as unprepared CSs. New evidence was obtained for a preparedness effect during acquisition trials: Only Ss receiving phobia-relevant stimuli developed an acceleratory cardiac conditioned response (CR). This acquisition effect was more reliable across experiments than the electrodermal extinction findings and showed less influence of CS—UCS "belongingness." Findings suggest that the preparedness effect is complexly determined and provide evidence that phobic stimuli occasion a unique pattern of conditioned visceral response. (48 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analyse des gaz et processus reactionnels anodiques dans les bains cryolithe—alumine

The composition of anode gas is an important indication for the mechanism of the electrolysis in cryolite-alumina melts. An original technique has been used for the captation of gas in situ (hollow graphite electrode under vacuum inside). The composition of anode gas was determined by mass spectrometry and shows that the nature of this gas depends on different factors such as the crystallographic structure of alumina (α-Al₂O₃, γ-Al₂O₃, hydrated alumina), the current density, the alumina concentration of the melt, the porosity and the B.E.T. area of carbon anode.The ratio [CO₂]/[CO] increases with increasing current density and descreases with increasing alumina content. The results suggest that CO₂ is the primary anode product which reacts partially with the anode following the Boudouard reaction.The structural water of the alumina (γ-Al₂O₃ or hydrated alumina) induces the formation of superficial COH complexes which lead to the passivation of the anode.A schematic representation of these mechanisms is proposed taking into account the kinetics of reaction during flow gas through the electrode walls. The contract time of gases with the carbon is an important factor in the mechanism of CO built up and the consumption of carbon by the anode process.     

基于DSP的M/T测速法改进

介绍了针对增量式光电编码器的新的数字测速方法——变M／T法,在此基础上设计了一种基于DSP的变M／T测速算法,论述了软硬件的实现方法．该方法在不增加硬件成本的前提下,使得电机测速具有更高的测量精度．     

Production and mechanical properties of aligned multi-walled carbon nanotubes-M140 composites

This study investigated the production of M140, aligned multi-walled carbon nanotubes (A-MWNTs) reinforced M140 composites (A-MWNTs-M140) and their mechanical properties including their compressive and bending properties as well as their microstructure characteristic of bend fracture surface. M140 was first produced by speed change mixing technics with commercial materials, water-bath curing at normal temperature. In addition, two different A-MWNTs dispersions including carbonyl dispersions of A-MWNTs (C-A-MWNTs) and aqueous dispersions of A-MWNTs (A-A-MWNTs) with the addition of 0.01wt% A-MWNTs were utilized to obtain enhanced mechanical properties with respect to plain M140. The results indicated that the use of A-MWNTs dispersions allows increasing compressive strength and flexural strength by 8.4% and 5.4%, respectively for the C-A-MWNTs-M140, and by 15.9% and 20.7% for the A-A-MWNTs-M140, respectively. The SEM and EPMA examinations of fracture surface also showed that the bond interface between the nanotubes and matrix is moderate and the main reinforcing mechanisms are microfilling effect, CNTs pull-out and debond. The aqueous dispersion of A-MWNTs is an appropriate method and is more compatible with the M140. Supported by the National Natural Science Foundation of China (Grant No. 50438010)     

N0-矩阵的模最小特征值的估计

在M-矩阵和逆M-矩阵的Hadamard积的性质的基础上给出了N0-矩阵的几个性质,并讨论了N0-矩阵和逆M-矩阵Hadamard积的模最小特征值以及N0-矩阵的模最小特征值的估     

Surface deformation at the epicenter of the May 12,2008 Wenchuan M8 Earthquake,at Yingxiu Town of Sichuan Province,China

Surface deformation,along National Highway 213 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,China,is surveyed and measured in detail.The results show two distinct characteristics.One is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72 m,and the short-ening amount is 0.38 m,which reflects thrust shortening deformation is not obvious.The crust uplift amount of ...     

一类Mobius变换在区域自同构中的应用

研究了复平面中区域的自同构问题.通过一类Mobius变换,给出了区域的任一自同构的表示形式;在区域和单位圆盘共形等价的条件下,证明了区域到单位圆盘的所有解析函数的导数在区域给定点处的模的上确界是可达的.     

80tonX58mH35M门式起重机柔性支腿的有限元分析

针对目前起重机的试验现状,提出了利用SolidWorks结合Simulation对80tonX58mH35M门式起重机柔性支腿进行三维建模和空间受力分析,在一定程度上替代了实际工程试验并突破了其局限性.利用计算机辅助分析方法对80tonX58mH35M门式起重机柔性支腿进行试验仿真研究,从而为设计80tonX58mH35M门式起重机及其重要结构件提供了信息,解决了样机试验中存在的问题.     

LTE系统中M2M业务随机接入优化方案

针对LTE系统中海量M2M终端同时接入引起的频繁碰撞问题, 提出一种基于分组的解决方案。将同一小区内的M2M终端划分成组并引入组长节点, 由组长代表本组发起接入请求, 基站根据当前负荷情况分配接入资源并通过组寻呼触发组员节点的随机接入过程。理论分析和系统级仿真实验结果表明, 相比LTE系统, 现有的随机接入策略新方案在终端数量较多时能够有效减少碰撞次数, 提高首次接入的成功概率。     

国际参考电离层关键输入参数计算及应用

国际参考电离层的关键输入参数是F2层临界频率foF2和传输因子M(3000)F2,文章给出了关于这两个参数的详细计算流程,分析了F2层临界频率foF2和峰值高度hmF2随时间和季节的变化情况,以及F2层峰值电子浓度NmF2和地磁纬度的关系,并简要介绍IRI模型在短波三维数字射线追踪中的应用。