我院获一项国家发明专利

由建工系教授级高级工程师张书良主持的深圳市科技局项目“建筑结构工作应力现场检测方法”近日获得国家专利局授予的发明专利权。该专利发明了一种建筑结构工作应力检测的新方法。这种方法是在被测建筑结构构件局部开一浅槽,然后采用电测法测得应变释放值。由于槽深与应变释放率存在相关关系,可以根据应变释放率标定值和实验所建立的数学模型,确定已受力结构构件的工作应力大小和方向。本方法可准确地测得建筑结构在各种荷载以及各种原因所产生的应力大小和方向,具有操作简便、测试精度高、费用低廉、受现场环境影响小等优点,适用于建筑物…     

浅谈盲孔法测焊接残余应力电阻应变片粘贴技术

盲孔法测焊接残余应力是学生实验中及工程上常用的对构件进行应力分析的实验方法之一,它由于具有操作简便、测量可靠性高、对构件损伤程度小等特点,而在焊接残余应力测试中获得了广泛的应用。在盲孔法测应力实验中,应变片的粘贴好坏将直接影响测试结果的准确性和可靠性。本文结合大口径厚壁X80管残余应力测定项目试验中几百个应变片的粘贴经验,总结出简单易行的操作工艺,以期在测试中为学生和工程技术人员提供有意义的指导和借鉴。     

MSC.Marc有限元分析软件在焊接残余应力和变形模拟中的应用

焊接是工程制造领域广泛使用的一种高效构件成型制造技术,但焊接过程中因焊接局部加热而形成的残余应力和变形是在工程制造中不希望出现的。焊接数值模拟能较为准确预测焊接构件中的焊接残余应力和变形的分布情况,可用以指导制造过程中焊接工艺参数的优化和焊接顺序的选择,为降低试验成本和缩短产品制造周期提供了一种可行的方法。对MSC.Marc软件焊接模拟热源模型、材料模型以及其在焊接残余应力和变形模拟中的应用情况作了介绍。     

试论预加应力在建筑结构中的应用

采用预加应力的方法可以改善构件的受力状态，使结构受力更趋合理。文章概述了预加应力在砼结构、钢结构等建筑结构中的广泛应用，着重介绍了高效预应力结构应用中需注意的几个问题。     

平面应力状态分析中任意两截面上应力的新解法

在乎面应力状态分析中，通过取出受力构件内某点的应力状态，便可以求出任意斜截面上的应力和主应力，从而对复杂受力构件作强度计算。这是单元体上两微面间相互垂直的特殊情况下进行的。当两微面相互不垂直时，求解未知应力就比较因难。本文经过研究，找出了任意两截面上应力之间的关系，并研究用应力圆表示。这对求解复杂受力构件内任意两截面上的应力，带来较大的方便，提供了一个新的方法，并举例说明它的应用。     

二层刚架结构模型在力学教学实验中的应用

为了深化基础力学实验教学的改革，该文应用力法求解超静定结构的应力分布，并与工程实际结合，设计开发了二层刚架工程结构模型试验装置，为本科生开设了“工程结构电测应力分析”实验。通过对刚架单根柱的实验测试和理论计算求得的应力分布，一方面使学生由单个受力构件的应力分布可推测二层刚架整体结构的应力分布概况，验证了该教学实验的综合性和创新性；另一方面通过实验偏差的分析，使学生认识到实际工程结构与理论模型之间的偏差是客观事实，从而确立实验在工程实际中是必不可少的思想意识。     

钢制压力容器分析设计中应力的分类及比较

钢制压力容器的分析设计中,依据JB4732-95《钢制压力容器——分析设计标准》,按＂等安全裕度原则＂应力分为三类：一次应力、二次应力、峰值应力。一次应力没有自限性,必须满足外载和静力平衡关系,按沿厚度分布情况又分为一次薄膜应力与一次弯曲应力;二次应力具有自限性,由同一元件上不同部位材料或相邻元件间的总变形协调条件导得;峰值应力的明显特点是局部性和自限性,是局部结构不连续处总应力去除一次应力和二次应力后的剩余应力。     

大跨径钢筋砼肋拱桥静载试验及有限元分析

为了检测净跨径133 m的大桥现况的整体结构性能和承载能力，对该桥主桥进行了汽车静载试验。静载测试采用6部载重汽车，分成4种工况加载，测算出拱肋截面应变、应力及挠度、桥面挠度、吊杆变形及应力等实测值，与建立有限元模型分析计算出的理论值进行对比，得知应力及挠度实测值均小于理论值，吊杆安全系数大于设计安全系数，桥梁构件强度及刚度均满足设计要求，表明该桥梁满足汽-20、挂-100的设计通行能力。     

有限元法应用软件ALGOR FEAS在强度设计中的使用

工程构件的应力应变分析是工程结构设计乖制造的基础,分析的精度乖正确直接关系到结构设计的安全性乖合理性．本文通过对有限元法、有限元分析软件ALGOR FEAS的简单论述,用一个薄板钢制杯状构件的应力应变分析说明了应用有限元法软件应注意的几个问题,以便该软件能被广泛使用。     

基于微波测试木材湿度引起内应力的方法研究

本文探讨了一种新的测试木材中由于湿度引起内应力的方法。基于微波传输特性,木材中的内应力可以通过木材中湿度的含量和微波衰减量对应的的电压来估测。表明了利用微波来测试应力的可能性,核心是将应力公式转换成电源电压单一变化的函数形式。运用该公式来进行测湿实验,测试的应力和观测的数据很吻合,并可以实现无损测试。得出用微波无损方式测试木材中由于湿度引起的应力是可行的结论。     

Stress,coping strategies and academic achievement in teacher education students

University students experience stress, and how they cope with this stress affects their academic achievement. This study examined stress in teacher education students and had three objectives: to describe different degrees of stress and coping styles; to study the relationship between stress, coping strategies and academic achievement; and to examine whether increased age can moderate the effects of stress on academic achievement in 334 university-students. There were three main findings: many students experienced stress and used avoidance coping strategies; the students who were under less stress and engaged less in cognitive avoidance and more in problem-focused coping were also the students who made more academic achievement; and students under more stress performed worse, but with age stress affected performance less. In teacher education students, it is important to recognize and address the harmful effects of stress on well-being and academic achievement, to avoid long-term problems in professional and personal life.     

Taste and emotionality in rats selectively bred for high versus low saccharin intake

Rats were selectively bred for high versus low saccharin ingestion, a putative measure of enhanced stress and emotionality (Dess, 1991). In Experiment 1, third-generation Occidental high-saccharin (HiS) and low-saccharin (LoS) rats were tested for saccharin ingestion and emotionality. The saccharin test confirmed that the lines differed on the selection phenotype. In addition, LoS rats were more emotional, as evidenced by longer emergence latencies and more defecation in a modified open-field test. In Experiment 2, LoS rats had lower quinine preference scores and drank saccharin-adulterated glucose less avidly. These outcomes are reminiscent of the behavior shown by inescapably shocked rats. Unlike helpless rats, however, LoS rats drank less avidly during a dilute sucrose test, an effect more reminiscent of chronic mild stress. The lines did not differ reliably on intake of concentrated glucose or Polycose, even when the latter was mixed with saccharin. In Experiment 3, LoS rats preferred saccharin less strongly than did HiS rats at concentrations of 0.05% to 0.7% and had an aversion to a 1.0% solution. In Experiment 4, LoS rats were affected more by shock, as assessed by stress-induced anorexia. These and other recent findings support the notion of shared mechanisms for taste, emotionality, and stress vulnerability.     

Low Income African American Mothers' Parenting Stress and Instructional Strategies to Promote Peer Relationships in Preschool Children

This study investigated mothers' stress as a predictor of her instructional strategies for promoting peer relationships in preschool children. Forty-two low income African American mothers responded to structured interviews on the teaching strategies they frequently used to facilitate peer interactions of their two to three- and-a-half-year-old children. Mothers' stress was measured by The Parenting Stress Index-Short Form. Using regression analysis, three stress predictors of mothers' strategies to promote peer relationships were examined: parental distress, difficult child, and parent-child dysfunctional interactions. The three predictors of stress had a differential impact on mothers' instructional strategies. As stress increased: (a) when teaching their own children, mothers more frequently used strategies that reduced antisocial behaviors and less frequently used the strategies that promoted pro-social behaviors towards peers; (b) when teaching their children's peers, mothers less frequently used strategies that would directly benefit these children. Educational implications of these findings for stressed parents, professionals who work with stressed parents, as well as those professionals who teach parent educators are examined.     

Low Income African American Mothers' Parenting Stress and Instructional Strategies to Promote Peer Relationships in Preschool Children

This study investigated mothers' stress as a predictor of her instructional strategies for promoting peer relationships in preschool children. Forty-two low income African American mothers responded to structured interviews on the teaching strategies they frequently used to facilitate peer interactions of their two to three- and-a-half-year-old children. Mothers' stress was measured by The Parenting Stress Index-Short Form. Using regression analysis, three stress predictors of mothers' strategies to promote peer relationships were examined: parental distress, difficult child, and parent-child dysfunctional interactions. The three predictors of stress had a differential impact on mothers' instructional strategies. As stress increased: (a) when teaching their own children, mothers more frequently used strategies that reduced antisocial behaviors and less frequently used the strategies that promoted pro-social behaviors towards peers; (b) when teaching their children's peers, mothers less frequently used strategies that would directly benefit these children. Educational implications of these findings for stressed parents, professionals who work with stressed parents, as well as those professionals who teach parent educators are examined.     

Reading the Fine Print

Students are frequently subject to considerable stress that may become distress during academic semesters. But this stress occurs at more or less regular intervals that can be predicted at the outset of the semester. Further, some students' obligations at the beginning of the semester predict that they will suffer distress later on. This paper describes a program that consists of some principles of time and stress management, two informal models of student stress, and steps that students can take to lessen distress. Goals are: (1) to reinstate psychologically students' past academic distress as a way of making them more receptive to suggestions for avoiding such predictable distress in the future; (2) to help students see that their distress results in part from procrastination; and (3) to induce them to try to reduce stress that normally comes later in the semester by increasing it at the outset.     

倾斜的结构——“革命＋恋爱”小说结构分析

“革命 恋爱”是“革命 恋爱”小说的深层结构。革命与恋爱在文本中有两种倾斜,即在篇幅上对恋爱的叙述多于对革命的描绘,在价值取舍上强调革命而忽视恋爱。革命与恋爱表现出三种关系,即矛盾冲突关系、相辅相成关系和平行关系。     

Predictors of parental stress in mothers of young children with hearing loss

This study examined parental stress in 184 hearing mothers of young children who are deaf or hard of hearing. Stress levels were measured in three domains using the short-form of the Parental Stress Index (PSI; Abidin, 1995). Mothers in this study demonstrated significantly less parental distress on the PSI than a normative, hearing group, although this difference was quite small. Differences between the hearing and hearing loss samples did not reach conventional levels of significance for the Dysfunctional Parent-Child Interactions or the Difficult Child subscales. An examination of potential predictors of maternal stress revealed that mothers who perceived their daily hassles as more intense also obtained higher stress ratings on all three subscales. Additional predictors of parental distress were frequency of hassles, social support, and annual family income. Increased stress on the Dysfunctional Parent-Child Interaction subscale was predicted by children who had disabilities in addition to hearing loss, more delayed language relative to their chronological age, and less severe degrees of hearing loss. No additional, significant predictors were obtained for the Difficult Child subscale. When all measured variables were controlled for, characteristics that did not predict maternal stress on any of the three subscales included the child's gender, ethnicity, age of identification, mode of communication used, maternal education, and months between age of identification and child age at the time of observation.     

Psychological Maladjustment and Academic Achievement: A Cross-Cultural Study of Japanese, Chinese, and American High School Students

American, 1,633 Chinese, and 1,247 Japanese eleventh-grade students, 5 indices of maladjustment included measures of stress, depressed mood, academic anxiety, aggression, and somatic complaints. Asian students reported higher levels of parental expectation and lower levels of parental satisfaction concerning academic achievement than their American peers. Nevertheless, Japanese students reported less stress, depressed mood, aggression, academic anxiety, and fewer somatic complaints than did American students. Chinese students reported less stress, academic anxiety, and aggressive feelings than their American counterparts, but did report higher frequencies of depressed mood and somatic complaints. High academic achievement as assessed by a test of mathematics was generally not associated with psychological maladjustment. The only exception was in the United States, where high achievers indicated more frequent feelings of stress than did low achievers.     

教育交往中的言语困境探讨

现实语言是教育交往的媒介。语言只有转化为直接性的言语才能实现真正的教育交往。教育交往中的言语是言语主体在相互言说中表现“存在的事件”与“意义的生成”,是主体生命的自我表述。然而,教育交往中的言语已因缺失和异化而产生困境。具体表现为:言语主体,重教师话语霸权轻双向对话;言语目的,重工具性价值轻目的性价值;言语内容,重本源轻流传;言语过程,重感知轻体验;言语理解,重符应轻生成。教育交往中言语困境产生的缘由包括:教育疏离生活世界,教育价值取向的效率主义与教师权威的泛化等。走出教育交往中的言语困境必须:消解中心,加强对话;重构言语环境,激活主体意识;丰富言语内容,注重体验生成;回归生活世界,指向人生意义。