玻纤格栅在防治反射裂缝中的应用

与沥青路面相比,水泥混凝土路面的修复比较困难,在旧混凝土路面上加铺沥青罩面层是一种改善其使用性能的有效措施,但在沥青加铺层中出现反射裂缝仍是需要解决的主要问题。反射裂缝本身对罩面层的使用性能影响不大,但环境因素(雨雪、氧化、粉尘)的负效应,常常使得裂缝迅速向四周扩展,缩短罩面层寿命。为了能有效地减缓旧水泥混凝     

Influence of soaking temperature on microstructure of multi-pass compression deformation for low carbon steels

The influence of soaking temperature on microstructure of high temperature multi-pass compression deformation for two low carbon steels (steel A: w _C = 0.032% and w _Mn = 0.25%; steel B: w _C = 0.165% and w _Mn = 0.38%) is studied on the thermal-mechanical simulator in order to rationalize the hot-rolling schedule of low-carbon steel and to promote the low-temperature heating technology. The results show that the microstructures of steel A are almost not affected by reducing soaking temperature, but the acicular ferrite forms in steel B when the soaking temperature is reduced from 1 200 to 1 170°C, due to its smaller initial austenite grain size according to recrystallization kinetics theory.     

无砂混凝土性能试验分析

对无砂混凝土性能进行了试验分析,结果表明无砂混凝土具有较高的力学强度、较小的收缩性能、较好的疲劳性能和排水性能.与常用半刚性基层材料相比具有优越的路用性能.     

发挥国家示范院校带动作用促进特色高职院校建设

本文简要概述了创办特色高职院校的必要性与"特色"的内涵,明确了"特色"高职建设的主要内容:办学体制机制创新,特色专业与专业群建设,人才培养模式改革,师资队伍建设和特色校园文化建设。大力发展中国特色的职业教育,坚持走中国特色的职业教育发展路子,发挥示范院校的引领作用,带动高等职业教育加快改革与发展,深化教育教学改革、创新人才培养模式、建设高水平专兼结合专业教学团队、提高社会服务能力和创建办学特色,逐步形成结构合理、功能完善、质量优良的高等职业教育体系,更好地为经济建设和社会发展服务。     

Modified gray level difference-based thresholding segmentation and its application in X-Ray welding image

Thresholding is a popular image segmentation method that often requires as a preliminary and indispensable stage in the computer aided image process, particularly in the analysis of X-ray welding images. In this paper, a modified gray level difference-based transition region extraction and thresholding algorithm is presented for segmentation of the images that have been corrupted by intensity inhomogeneities or noise. Classical gray level difference algorithm is improved by selective output of the result of the maximum or the minimum of the gray level with the pixels in the surrounding, and multi-structuring of neighborhood window is used to represent the essence of transition region. The proposed algorithm could robustly measure the gray level changes, and accurately extract transition region of an image. Comparisons with other approaches demonstrate the superior performance of the proposed algorithm.     

基于JADE算法的矢量水听器阵列信号盲估计研究

标量声压水听器线阵无法估计信号的二维到达角（方位角和俯仰角）,并且对来波方向相同的信号无法分辨.针对这一情况,文中引入盲信号处理理论,将JADE（特征矩阵联合近似对角化）算法与矢量水听器阵列技术相结合,提出了一种新的阵列信号盲估计算法.该算法应用在结构简单的矢量水听器线阵上,在信号方向矢量没有任何先验知识情况下,对阵列流型矩阵进行盲估计,进而估计出源信号的频率和二维到达角,并实现对来波方向相同信号的辨识.仿真实验证明了算法的有效性.     

胶粉掺量对橡胶改性沥青低温性能的影响

通过弯曲梁流变(BBR)试验分析不同掺量橡胶改性沥青以及胶粉复合SBS改性沥青的低温性能。结果显示,随着胶粉掺量的增加,橡胶改性沥青的劲度模量逐渐下降,蠕变速率逐渐增加,沥青逐渐变软,低温变形以及应力消散能力逐渐提升,低温性能逐渐提升;当胶粉掺量达到18%时,其低温PG分级相较于基质沥青可提升一个等级。对于胶粉复合SBS改性沥青,随着SBS的加入,橡胶改性沥青的劲度模量稍有提高,然而蠕变速率也增加,说明加入SBS使得橡胶改性沥青变硬的同时,也提升了其低温变形能力以及应力消散能力;当胶粉掺量从5%增加至18%时,其低温劲度模量降低约50%。     

上海市南浦大桥浦东引桥设计

<正> 南浦大桥是上海市市区第一座跨越黄浦江联接浦西市区与浦东开发区的大桥,桥位在浦西岸位于南市区南码头人行渡口处,浦东岸位于上海港务局预制品厂内,主桥为一跨过江的双塔双索面斜拉桥,主跨423米,全长765米,主桥的主梁为钢梁与钢筋混凝土桥面