首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9篇
  国内免费   1篇
  综合类   10篇
  2016年   1篇
  2015年   1篇
  2014年   2篇
  2013年   1篇
  2012年   1篇
  2011年   1篇
  2008年   2篇
  2005年   1篇
排序方式: 共有10条查询结果,搜索用时 156 毫秒
1
1.
玻纤增强热塑性塑料制品"浮纤"现象改善措施研究   总被引:1,自引:0,他引:1  
文章分析了玻纤增强热塑性塑料制品“浮纤”现象的形成原因和杌理,提出了一系列改善方法和措施,并结合汽车把手面盖制品的生产实践,重点阐叙了通过调整模具结构、优化注射成型王艺条件等途径来有效改善“浮纤”现象的技术要点。  相似文献
2.
The temperature distributions of a prestressed concrete box girder bridge under the effect of cold wave processes were analyzed. The distributions were found different from those under the effect of solar radiation or nighttime radiation cooling and should not be simplified as one dimensional. A temperature predicting model that can accurately predict temperatures over the cross section of the concrete box girder was developed. On the basis of the analytical model, a two-dimensional temperature gradient model was proposed and a parametric study that considered meteorological factors was performed. The results of sensitivity analysis show that the cold wave with shorter duration and more severe temperature drop may cause more unfavorable influences on the concrete box girder bridge. Finally, the unrestrained linear curvatures, self-equilibrating stresses and bending stresses when considering the frame action of the cross section, were derived from the proposed temperature gradient model and current code provisions, respectively. Then, a comparison was made between the value calculated against proposed model and several current specifications. The results show that the cold wave may cause more unfavorable effect on the concrete box girder bridge, especially on the large concrete box girder bridge. Therefore, it is necessary to consider the thermal effect caused by cold wave during the design stage.  相似文献
3.
基于苏通大桥辅助航道桥运营期两年内实测的温度、气象和应变数据,对混凝土箱梁的有效温度与应变进行了分析。结果表明:箱梁的尺寸越小,有效温度变化的范围越大,设计基准期为100年的墩顶梁和跨中箱梁的有效温度范围分别为(-4.3℃,37.3℃)和(-6.1℃,42.2℃);大气前3天的最高(低)平均温度与箱梁有效温度的相关性系数高达0.97,通过回归分析得到的箱梁有效温度与大气前3天平均最高(低)温度的关系式,可用来对箱梁有效温度进行预测。最后提出了修正混凝土收缩、徐变效应的方法,并使用箱梁有效温度对主墩墩底混凝土的竖向相对应变和支座截面箱梁顶板混凝土的纵向相对应变进行了预测。  相似文献
4.
针对内存管理中虚拟页面和物理页面连续分配的特性,提出可对相邻页面进行动态合并的旁路转换缓冲器(TLB)设计方法.该方法的核心思想是在处理器运行过程中,通过对相邻页面的递归合并,动态扩展单个TLB表项的地址映射范围,提高TLB表项的利用率并降低TLB缺失率.在两级TLB架构中,提出基于快速uTLB(fuT-LB)和影子uTLB(suTLB)动态切换的新型uTLB结构,作为两级TLB架构的一级缓存,为页面动态合并提供现场和载体,页面合并过程对软件透明.基于Mibench测试基准的实验结果表明,与filter-TLB架构相比,该页面动态合并方法可以平均降低TLB缺失率达27%.  相似文献
5.
In order to realize information construction on settlement of pile-group foundation of Sutong Bridge, the monitoring instruments of high-precision micro-pressure sensor and hydrostatic leveling and settlement profiler were integrated synthetically. A set of practical multi-scale monitoring system on settlement of super-large pile-group foundation in deep water was put forward. The reliable settlement results are obtained by means of multi-sensor data fusion. Finite element model of pile-group foundation is established. By analysis of finite element simulated calculation of pile-group foundation, rules of settlement and uneven settlement obtained by monitoring and calculation results are coincident and the absolute error of settlement between them is 4.7 mm. The research shows that it is reasonable and feasible to monitor settlement of pile-group foundation with the system, and it can provide a method for the same type pile-group foundation in deep water.  相似文献
6.
异构数据库的集成问题是当前数据处理领域内研究的一个热点。本文在分析了异构数据库系统的关键问题和解决方法的基础上.提出了一个基于网格和XML的异构数据库集成模型。并重点分析了该模型的结构和实现方法.该模型采用XML作为信息传输的数据格式,通过GT4网格计算中间件来实现对各异构数据源的高效访问。  相似文献
7.
8.
提出基于Haar小波变换的虹膜识别算法.通过Haar小波变换对归一化虹膜图像进行特征提取,运用Hamming距离对2个虹膜特征进行模式匹配.与Daugman的虹膜识别算法比较,该方法在编码长度和编码时间上都有较明显的改进,且算法具有良好的鲁棒性,可用于实际的身份鉴别系统中.  相似文献
9.
根据氧化铝陶瓷的结晶形态,分析了95氧化铝陶瓷高硬度和高脆性的机理;根据相关文献资料介绍了氧化铝陶瓷的主要加工方法及特点。  相似文献
10.
为了解决火炮任意射角弹丸卡膛姿态高精度、高可靠性测试关键技术,基于PSD激光成像测试原理,提出了弹丸卡膛姿态测试方法.以反映弹轴姿态角的激光器固定在弹头、探测器固连到炮口以接收弹头激光信号、并同时测试身管弯曲变形以修正测试结果.研制了弹丸卡膛姿态测试系统,实现了火炮任意射角弹丸卡膛姿态测试,完成了某火炮弹丸卡膛姿态规律实验研究.结果表明,所选火炮弹丸卡膛姿态规律表现为高低以低头输弹、左右基本呈现对称输弹、弹丸前定心部接触膛线后摆动约1周后卡膛,卡膛姿态角度最大值均小于5′.提出的测试方法和研制的测试系统通过了实际火炮工程应用验证,满足工程应用要求.  相似文献
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号