烟囱倾倒时最容易断裂的位置     

肖庆华 《重庆职业技术学院学报》2004,13(1):99-100

烟囱倾倒过程中,通过对横截面上切应力及拉伸(压缩)应力的计算,确定了倾倒时烟囱被破坏的主要力学原因及表现是,在外侧强大的拉应力作用下,烟囱从外侧开始被拉断.  相似文献   

温度计在三峡大坝安全监测中的应用     

李楠 《实验技术与管理》2006,23(8):25-27,46

坝体混凝土在水化热、水温、气温、太阳辐射等因素的影响下,其内部温度发生变化会引起坝体裂缝等情况出现,因此,温度计作为大坝温度监测的一种有效手段,通过分析温度计的观测数据就可知坝体内部温度分布和变化的趋势.  相似文献   

Social Work Intervention with White Collared Employees and Their Families     

Y.?S.?SiddeGowdaEmail author 《International journal for the advancement of counseling》2004,26(4):421-432

This investigation presents a framework for understanding and also to test the efficacy of Social Work intervention on the well being of the white collared employee (industrial employee) and his/her family. A comprehensive and intensive personal- family exploration was done to uncover the relatedness of seemingly disparate areas of the clients lives. A total of 80 executives (industrial employees) served as subjects. A baseline assessment was done using structured, standardized interview-schedules/questionnaires. The results of the study can be enumerated as follows: After the Social Work intervention, the executives in occupational profile, there were significant changes in Role perception, overload, role conflict, low status and poor peer relations. In coping strategies there was significant improvement in sub-scales like problem solving and unproductive coping. Significant reduction was noticed in their proneness to heart disease, depression, inadequate mental mastery, and perceived ill health. There was significant improvement in their family group support, and in their expressiveness, achievement, orientation, active-recreational and organizational characteristics.  相似文献   

连续定态传热过程平均温差的统一推导     

琚行松  赵红丽 《唐山师范学院学报》2007,29(2):28-30

采用统一的方法对定态传热逆流和并流的平均温差进行了推导。推导过程无需假定冷热流体的特定流向,并利于得到对数平均温差“同侧相减”的规律。  相似文献   

弧形混凝土结构温度应力计算研究     

黎永索  卫军 《湖南城市学院学报》2003,24(6):10-13

对弧形混凝土结构温度应力的计算研究表明，弧形结构的环向应力沿高度方向基本一致，可以简化为拱单元计算，拱单元的支座约束可以用“等效暗柱”来计算；结构两侧温差对弧形结构的环向应力的影响较轴线温差变化的影响更大，控制温度裂缝主要是控制结构物两侧的温差．通过设置滑动层，减小结构的抗侧移刚度。则弧形混凝土结构可以作无缝设计．  相似文献   

Understanding college degree completion of students with low socioeconomic status: The Influence of the Institutional Financial Context     

Marvin A. Titus 《Research in higher education》2006,47(4):371-398

  相似文献   

Differential recognition of children's cultural practices in middle primary literacy classrooms     

Helen Nixon  Barbara Comber 《Literacy》2006,40(3):127-136

This paper argues that teachers' recognition of children's cultural practices is an important positive step in helping socio‐economically disadvantaged children engage with school literacies. Based on 21 longitudinal case studies of children's literacy development over a 3‐year period, the authors demonstrate that when children's knowledges and practices assembled in home and community spheres are treated as valuable material for school learning, children are more likely to invest in the work of acquiring school literacies. However, they also show that while some children benefit greatly from being allowed to draw on their knowledge of popular culture, sports and the outdoors, other children's interests may be ignored or excluded. Some differences in teachers' valuing of home and community cultures appeared to relate to gender dimensions.  相似文献   

光学分层成像法重建火焰温度场的理论和实验研究     

汪凤林  王式民  陆勇 《东南大学学报》2001,17(2)

提出了一种测量三维火焰温度的新方法 .根据光学分层成像理论 ,三维火焰可以看成若干个互相平行的二维发光断层的组合 .用高速摄像控制系统沿着某一固定方向对火焰进行分层聚焦摄像 ,得到一组辐射图像 ,每个图像都是其对应断层的聚焦像和其它断层离焦像的叠加像 ,运用图像反演算法 ,即可重建各断层的原始图像 ,再用彩色三基色测温方法 ,处理所得到的原始图像 ,即可建立火焰的三维温度场 .通过蜡烛火焰的试验 ,验证了该方法的可行性  相似文献   

对跳远两种技术的初步探讨     

毛立力 《宁波教育学院学报》2002,4(1):53-55

以世界优秀跳远选手刘易斯和埃米扬的典型两跳为参照,分析了我国优秀跳远运动员在助跑速度、绝对速度、速度利用率、腾起角度与两选手之间的差异,提出了近期内练就刘易斯一样以速度见长的技术特点（低跳跃型）可能性不大的情况下,适度调整垂直速度和水平速度的比例,降低助跑速度利用率,增大腾起角,走埃米扬力量见长（高跳跃型）技术之路,是我国优秀跳远运动员提高成绩的有效途径。  相似文献   

大体积混凝土温度应力造成裂缝的控制     

ZHENG You wei 《福建工程学院学报》2001,(Z1)

分析大体积砼温度裂缝 ,提出降低温度应力、防止大体积砼裂缝几项措施  相似文献