Study on properties of residue-residue contacts in protein

INTRODUCTION Recognition of protein folding from aminoacid sequence is a challenging task. The structureand stability of proteins from different fold aremainly dictated by inter-residue interactions. In-formation on the distribution of contacts shown by20 amino acid residues can be used to predict thefolding type of each protein (Chan and Dill, 1998;Zhang and Kim, 2000; Gromiha, 2001; Gromihaand Selvaraj, 1999; Miyazawa and Jernigan, 1985;1996; Bahar et al., 1997; McDonald and …     

Study on properties of residue-residue contacts in protein

Residue-residue contacts are very important in forming protein structure. In this work, we calculated theaverage probability of residue-residue contacts in 470 globular proteins and analyzed the distribution of contacts in thedifferent interval of residues using Contacts of Structural Units (CSU) and Structural Classification (SCOP) software. Itwas found that the relationship between the average probability -PL and the residue distance L for four structural classes ofproteins could be expressed as lgPL=a b×L, where a and b are coefficients. We also discussed the connection between twoaspects of proteins which have equal array residue number and found that the distribution probability was stable (or un-stable) if the proteins had the same (or different) compact (for example synthase) in the same structural class.     

基于Matlab的直流电动机双闭环调速系统的仿真研究

分析了直流调速系统的原理和工程设计方法,详细介绍了基于Matlab/Simulink的双闭环直流调速系统仿真和建模设计。教学实践表明,通过仿真可以帮助学生理解直流调速原理。     

基于Matlab的直流电动机双闭环调速系统的仿真研究

分析了直流调速系统的原理和工程设计方法,详细介绍了基于Matlab/Simulink的双闭环直流调速系统仿真和建模设计。教学实践表明,通过仿真可以帮助学生理解直流调速原理。     

Experiencing failure in the classroom and across the university

ABSTRACT

In this article, 10 award-winning post-secondary instructors use narrative inquiry to explore failure individually by reflecting on their own definition and framework of failure, by giving examples of their experience with failure, and by elaborating how they deal with and learn from failure. The outcome of this collective exploration is an article that reflects the reality of life in academia where members of the academic community face failures, their own and those of others, on a daily basis.     

网络文化中的网络语言研究——以虚拟交往中的网络语言为例

以虚拟交往中使用的网络语言为研究对象,通过对具体的网络语言的内容、形式、特点进行简要分析,进而探讨网络语言与网络文化的关系。我们认为,网络语言是网络文化的重要组成部分,一方面网络语言受网络及网络文化影响;另一方面,网络语言在一定程度上影响网络文化。因此,理解网络语言需要将其置于特定的文化背景中。     

弯曲件冷冲模失效分析

通过对弯曲件冷冲模各加工工艺和金相显微组织的分析，分析了冷冲模产生裂纹的原因，并提出了防止裂纹产生的工艺措施。     

Wise academic development: learning from the ‘failure’ experiences of retired academic developers

ABSTRACT

Informed by Constructive Developmental Theory and the Threshold Concepts Framework, we interviewed retired academic developers from four continents and asked them to describe their processes of learning from perceived failures and how they see the role of academic developers in supporting academics through failures. Findings regarding participants’ definitions of failure, ways of making sense of and learning from failure, and recommendations for supporting academic colleagues’ learning from failure are shared through tables, quotations, and poetry. Findings show that ‘wise academic development’ embraces curiosity about failure, integrates the (sometimes) transformative nature of failure, shares the load of sense-making, and cultivates connectedness.     

Noise properties in breaking and loose contacts and their effect on quality degradation of digital signal

Electric contact discharge is subject closely related to digital information transmission, and integrity of digital signals for realizing high reliablility transmission. This kind of problem is a part of EMC (electromagnetic compatibility). From such a viewpoint, contact noise problems will be mentioned which disturb and degrade digital signals. The induction noise and radiation noise from discharge, electrostatic discharge (ESD), and connector related fundamental subject will be mentioned.     

对《电路》实验教学的探讨

《电路》实验是电路课程中的一个重要的教学环节,它是培养学生动手能力、独立分析与解决问题能力、理论联系实际能力以及创新能力的重要教学手段之一.     

从文明无知、文明冲突到文明交往、文明和谐--对学术界三种文明观的基本述评

文明是决定和影响人类活动的长期的基本因素。冷战结束后，特别是随着“文明冲突论”的提出，各种文明观的讨论逐渐演化成文明学的各种派系。当前主要有三种文明观：文明冲突论、文明对话论、文明交往论。在处理国与国关系的实践中应承认并维护文明的多样性。文明发展的趋势是文明和谐和文明相处。人类真正的危险在于各个民族、国家间文明的互不相融，以及由此导致的误解、紧张、冲突乃至战争。世界的持久和平与持续发展有赖于人与人之间、民族与民族之间、国家与国家之间文明的对话、沟通和理解，有赖于文明间的和谐，共同发展。     

上软下硬地层隧道围岩渐进破坏机制分析

软硬结构面的存在阻断了岩体性质的连续性,结构面倾角的位置和角度会造成多种破坏模式。文章对上软下硬地层隧道的破坏过程和破坏模式进行数值模拟研究。结果表明:分界结构面倾角在30°～75°时隧道稳定性较差;围岩变形破坏特征在对称模式下,围岩位移、破坏区和塑性区呈对称分布;在非对称模式下,结构面倾角和围岩的力学参数决定了破坏区的位置和范围,破坏区的位置主要受结构面倾角的影响。     

Study on reliability technology of contactor relay

In this paper, the reliability of contactor relay is studied. There are three main parts about reliability test and analysis. First, in order to analyze reliability level of contact relay, the failure ratio ranks are established as index base on the product level. Second, the reliability test method is put forward. The sample plan of reliability compliance test is gained from reliability sample theory. The failure criterion is ensured according to the failure modes of contactor relay. Third, after reliability test experiment, the analysis of failure physics is made and the failure reason is found.     

试论跨文化交际中常见语用失误及排除措施

本文从语用学角度出发,分析了语用失误类型和产生原因,结合汉语教学的实践,提出在跨文化交际中培养民族学生语用能力致关重要,并阐述了避免和减少语用失误,提高汉语学习者语用能力的措施,以期向各位同仁赐教。     

纤维/织物增强复合材料层压板弯曲性能及破坏机理实验研究

针对不同纤维类型、不同树脂类型和不同增强方式的复合材料层压板进行了三点弯曲实验研究,得到了复合材料层压板的主要弯曲力学性能参数,分析了不同材料体系和增强方式对层压板弯曲力学性能的影响。对试件断口形貌进行了宏观观察,研究了不同增强方式复合材料层压板的变形及破坏机理。结果表明:纤维增强压板和织物增强层压板在破坏前均呈现明显的线弹性;纤维增强层压板相比织物增强层压板具有一定的后续承载能力,呈现"假塑性"特征,而织物增强层压板破坏则是明显的脆断,不同增强方式对复合材料的弯曲性能和破坏机理有明显的影响。该研究成果为进一步改进国产复合材料的设计及工艺水平提供了实验依据,也可用于其他类型复合材料相关力学性能的对比研究。     

制造业上市公司财务失败预警实证研究

采用主成分分析方法．选取沪深股市46家ST制造业公司及与之相对应的46家非ST制造业公司共92家企业作为研究样本．构建了用于预警制造型企业财务失败预警的主成分预警模型,并通过检验确定了预警模型的预警准确率。     

基于自动变速器的油质分析及故障判断

汽车自动变速器故障中因自动变速器油的问题引发的故障大约占到80％左右,其中,部分是由于自动变速器液面高度不正常而引起的,部分是由于自动变速器油变质或使用的自动变速器油不是既定牌号引起的,本文通过对油质状态进行认真仔细的研究分析,给出自动变速器油变质的原因,并进一步分析了油液变质后所能引起的故障。     

Multicultural contacts in education: a case study of an exchange project between different ethnic groups

One important aim of citizenship education is learning to deal with cultural diversity. To this end, schools organise exchange projects to bring students into contact with different social and cultural groups. The aim of this study is to investigate the effects of intergroup contact in educational settings and to understand what the most favourable conditions are. The paper discusses a case study on an exchange between 10th‐grade students of Surinamese and Dutch‐Antillean backgrounds from an Amsterdam suburb with native Dutch students from rural Netherlands. The study included interviews with teachers and students and pre‐ and post‐tests of intergroup attitudes. The results indicate that students become more aware of their own preconceived ideas. The results show that interaction on the individual level is important. Getting students to work together on common goals is an effective way of stimulating interaction.     

Application of the Bayes＇ theory to the failure rate evaluation of electrical apparatus

The Weibull distribution has been widely used in reliability fields. A mixed Weibull distribution represents a population that consists of several Weibull subpopulations. In this paper, a new approach which combines the least-squares method with Bayes＇ theorem, takes advantage of the parameter estimation for single Weibull distribution is developed to estimate the parameters of each subpopulation. The estimates given by this paper also satisfy the maximum likelihood equation. The estimates of the failure rate of the mixed Weibull population are given. An actual test data is computed by using the proposed method. The Kolmogorov-Smirnov goodness-of-fit test turns out that the proposed method yields more accurate result.     

岩体地震破坏机理及地球物理特性变异探讨

对强地震多发区黄河黑山峡下游段岩体破坏特征进行了分析,研究表明,地震作用下裂隙的生成与地震波的传播具有同时性、继承性和纵横渡在岩体破坏中的拉张和剪切共同作用的双重性等特点.对岩体地震破坏机理及岩体地震破坏模型进行了初步探讨.同时对地震破坏后岩体地球物理特性的变化进行了研究,发现研究区大范围地球物理参数明显变异,说明强震对坚硬的岩体同样具有严重的破坏性.