冷轧薄宽带钢局部型中浪瓢曲变形行为研究

针对薄宽带钢冷轧过程中易发多发的局部型中浪瓢曲缺陷,引入非均匀载荷宽度、弹性约束系数及平均张应力建立了屈曲变形的解析计算模型。应用能量最低原理对屈曲变形区域进行搜索求解,得到了局部型中浪屈曲临界条件(包括临界应力、屈曲波长和屈曲波宽),获得了其与非均匀载荷宽度、弹性约束系数、平均张应力的关系,并发现平均张应力是产生局部型中浪的重要影响因素。应用样条有限元方法对局部型中浪进行数值仿真分析,验证了屈曲解析计算方法的正确性。在实验轧机上进行了轧制研究,通过轧制获得了局部型中浪屈曲模态,对实验结果分析得到了相对应的屈曲临界条件,与解析法和样条有限元法结果基本吻合,证明了样条有限元计算方法与解析计算方法的正确性及其工程应用价值。     

9.3大阅兵:高标准让军魂荡气回肠

<正>阅兵是展示辉煌的时刻,而为这一辉煌采取的所有的标准,不啻也是宝贵的财富,应当成为践行标准的榜样……这个月最令人难忘、最引人自豪、最提振国威的事情,当属"9.3"大阅兵,它有着以往没有的多重的亮点:首次以纪念抗日战争暨世界反法西斯战争胜利为阅兵主题,彰显维护和平是全世界人民共同的愿望。首次邀请外国军队代表参加分列式,体现纪念大会的国际性。首次组织抗战老兵包括国民党老兵参加,体现了对历史的尊重,体现全民族抗战的特色。首次编组英模部队方队受阅,展示中国共产党在抗战中定海     

云冈遗韵

<正>云冈石窟,历经1540年的人间风雨而硕立至今的那种坚强、博爱与宽容的佛国神界!这净25米高的崖壁上蜂窝般开凿出的是人间的奇迹,人类的智慧,     

分光光度计使用维护的注意事项

一、分光光度计检定的主要项目对分析结果的影响 1.波长准确度 分光光度法必须对应于样品吸收光谱中的某一个吸收峰的波长.但由于仪器本身存在的误差和不同的人员进行测量时产生的误差,单色光的实际波长与仪器的波长读数值之间会存在一定的误差.     

乡野如画醉金秋

秋天在不经意间早已悄然远去,留下的是那金色的记忆。乡野的秋色金灿灿。柿子树上硕果累累,红红火火的柿子和层次分明、错落有致的黑色枝干在弥漫的烟雾中若隐若现、飘逸洒脱,宛如一幅写意的国画。     

国内外仪器指标的接轨与合格判断

随着科学技术的发展和科研任务的需要,测量仪表的使用大幅度增加,因此检定的任务量也随之大幅攀升.其中国外仪表占了很大的比重,但在仪器技术指标的表达方式上国外各个厂家不尽相同,与国内计量术语和仪器技术指标的表达方式更是存在较大的差异,这对于仪器的使用和计量检定的合格性判断是一个重要的问题,关系到购置仪器的验收与使用,进而关系到科研任务的质量保障.     

甲醛气体传感器研究进展

甲醛是室内空气的主要污染物之一,随着人们对室内空气污染的日益关注,对甲醛的准确及时检测显得更加重要.目前检测甲醛气体最为快速的方法就是传感器法.在综合分析了国内外甲醛气体传感器的研究现状的基础上,着重就测定甲醛的电化学传感器、基于化学发光的传感器、金属氧化物传感器、电子鼻、声表面波传感器的特性进行了阐述与剖析,指出了甲醛气体传感器存在的问题,并预测了其发展趋势.     

世界著名自驾车露营地

<正>露营在国外已经拥有超过100年的历史,露营地的管理和经营方式大多参照了酒店,也有星级之分。随着人们需求的变化,露营地提供的设施和服务也在不断跟进。如今,在一些著名的露营地,已经不仅仅能够看到为自驾车、房车露营者提供的营位和日常生活的基础设施,还有诸如高尔夫、骑行、划船等形式多样的体育运动,以及像毗邻历史悠久的古村落这样的特色看点。在很多国家,建立一个享有声誉的汽车营地甚至成为了拉动旅游业发展的重要手段之一,也因此得到了政府的大力支持。     

汽车阳极电泳线改造为阴极电泳线的实践

为了将车身涂装线中的阳极电泳改造成阴极电泳,在保留前处理不变的前提下,首先布置合理的工艺流程、确定阴极电泳工作原理,然后对阴极电泳的电泳槽、漆液主循环系统、超滤系统、阳极液循环系统、热交换循环系统、阴极电泳电源和电泳后清洗系统的技术参数进行认真的分析和计算,使改造后的阴极电泳的各项技术指标达到了设计的要求.结果表明,通过局部的技术改造,将车身涂装线的阳极电泳改造成阴极电泳完全可行.     

家的幸福瞬间

家是心灵的港湾,让我们寄托一生;家是人生的加油站,让我们纾解疲劳。家是能铺开心事的地方,家是受伤时的创口贴,家是握在手里盈盈一脉的馨香,家是每一砖每一石都用爱砌出来的城堡。家是以爱为圆心,一家人手牵手为半径走过的一个圆;家是整个世界在下雪,走进其中却是春天的角落;     

基于超文本问题描述的供应链辅助决策模型

在分析基于全球供应链的虚拟企业模型和超文本技术的基础上,提出了基于超文本的供应链辅助决策模型。以某大型建筑企业的实际系统开发为背景,给出了基于超文本问题描述的供应链辅助决策系统结构。     

Citation analysis of Ted Nelson’s works and his influence on hypertext concept

This study investigates Ted Nelson’s works and the influence of his hypertext concept through citation analysis, including citation counting, characteristics of citing articles on language, document type, citing year, discipline, and citation content. The selection of the Nelson’s works was based on searching Library Literature & Information Science, Library and Information Science Abstracts, Google and Yahoo search engines. The citation data were compiled from the database of Web of Science. The results of the study reveal that hypertext has directly great impact on information retrieval and world wide web; therefore, the concept has had profound influence on information, library and computer science disciplines. Moreover, the influence of Nelson’s works spreads to other disciplines variously, especially on education, literature, business and economics, engineering, sociology, psychology, etc. The citation context analysis of citing articles on information and library science reveals that (1) definition, orientation and general introduction of hypertext; (2) relation of Vannevar Bush and Ted Nelson in terms of hypertext; (3) Nelson’s Xanadu system and its component of hypertext; (4) the application of hypertext in information science and library science are four most citing purpose.     

超文本可用性的两种实用评价方法

超文本可用性涉及到多种因素，可从不同的角度进行评价。文章概述了国外在这方面的研究进展，简要介绍了目前较常用的几种评价超文本可用性的方法，并对其优点与局限性进行了评价。     

MIKROPLIS: a hypertext system for design

MIKROPLIS is hypertext software for handling textual information representing designers' reasoning. It is based on PHI (procedurally hierarchy of issues), a refinement of the IBIS (issue-based information system) design method. This article explains the history of hypertext, the PHI variant of IBIS and the MIKROPLIS system itself.     

文本结构和个体认知风格对网上信息搜索绩效的影响

以中文阅读内容为实验材料,考察文本结构和个体认知风格对网上信息搜索绩效的影响。结果表明:(1)在信息规模较大的情况下,超文本的信息搜索时间少于纯线性文本,但迷路比线性文本严重;(2)在超文本情境下,被试更多地通过Back键来导航,而Home键相反;(3)没有发现个体认知风格的显著影响,认知风格对信息搜索绩效的效应需进一步探讨。     

不同呈现条件下景点信息内隐记忆的绩效研究

实验探讨了在不同呈现条件下阅读者对旅游景点获取的效果,旨在为网页和广告设计以及效果评估提供心理学依据。通过过程分离程序(PDP)的包含和排除测验计算超文本和线性文本的不同呈现条件下外显控制性加工和内隐自动化加工各自的贡献大小。结果表明：①超文本的内隐记忆绩效优于线性文本;②有图像的文本内隐记忆优于无图像文本;③超文本的外显记忆绩效优于线性文本;④外显控制性加工在同一阅读材料的不同呈现方式的记忆中无显著差异。结论：过程分离程序可以分离记忆的控制性加工和自动化加工,在设计一个网络时应考虑控制性加工效果和自动化加工效果。     

Fractal and informetric aspects of hypertext systems

The present paper studies fractal features (such as the fractal dimension) of hypertext systems (such as WWW) and establishes the link with informetric parameters. More concretely, a formula for the fractal dimension in function of the average number of hyperlinks per page is presented and examples are calculated. In general the complexity of these systems is high. This is also expressed by formulae for the total number of hypertext systems that are possible, given a fixed number of documents.     

Using Hypertext Metrics to Measure Research Output Levels

Two common ways to measure the "output" of a researcher (or research group) are to count numbers of publications and to count the citations (references to these publications in publications of others). These simple methods are flawed because they cannot easily take into account the differences in publication and citation habits in different scientific communities.An alternative approach is to view citations as hypertext links, and to use or adapt hypertext metrics to compare the scientific output of researchers, in comparison to that of others in areas with similar publication and citation patterns. We show how hypertext metrics, introduced by Botafogo, Rivlin and Shneiderman, can be modified in order to identify comparable research fields based on their publication and citation pattern. An author's performance can then be compared to that of others in research fields with a similar pattern.     

建筑制图CAI软件系统的设计与实现

对建筑制图CAI多媒体软件系统的超文本技术、系统的结构设计、软件的个性化设计及其实现等问题进行了详细的论述。     

Engaging and Supporting Problem Solving in Engineering Ethics

Learning to solve ethical problems is essential to the education of all engineers. Engineering ethics problems are complex and ill structured with multiple perspectives and interpretations to address in their solution. In two experiments, we examined alternative strategies for engaging ethical problem solving. In Experiment 1, students studied two versions of an online learning environment consisting of everyday ethics problems. Students using question hypertext links to navigate applied more perspectives and canons and wrote stronger overall solutions to ethics problems than those using embedded hypertext links. In Experiment 2, students engaged in a more generative task, evaluating alternative arguments for solutions to the cases or generating and supporting their own solutions. Both groups better supported their solutions and generated more counterclaims than control students. These studies focused on solving realistic case‐based ethics problems as an effective method for addressing ABET's ethics criteria.