神水泉大桥动力特性及地震作用分析

结合神水泉大桥的工程设计实例,采用大型有限元分析程序Midas Civil,选取空间梁单元建立动力计算模型,研究了桩土共同作用边界约束条件下的动力特性.采用反应谱法对该桥进行了E1地震作用分析,讨论了在CQC振型组合方法情况下结构地震响应的最大值,同时验算了E1地震作用下相关构件强度.     

大跨度连续梁0#块钢管支架设计与施工技术

青荣城际铁路跨青威高速公路特大桥(60+100+60)m连续梁工程,由于连续箱梁0#块面积小、体积大、重量达1 270t,桥墩高度近15m,对地基沉降、支架变形控制要求高。现浇支架采用钢筋混凝土临时支墩和钢管支架组合结构,钢管直接支撑在已浇筑的承台上。主要介绍了0#块现浇钢管支架采用MIDAS程序建立模型,进行钢管支架设计及强度、变形和稳定性检算,同时阐述了支架施工情况。实践证明钢管支架具有变形小、承载力大、施工周期短等优点,充分确保了连续梁0#块施工安全质量,节省了成本。     

越浪的湍动及流场分析

越浪一直是波浪水动力问题的一个难点,原因在于其形成受到多种强非线性现象的作用。应用一种新型数值波浪模型(0-1BEM+VOF耦合模型)对越浪过程进行研究分析,并探讨了湍动动能、动能耗散率及流场在周期内的变化趋势。     

基于机器视觉的农产品自动分选机机构设计

介绍了用于分选农产品的自动分选机的设计,包括机械结构的总体设计和主要机械部件的设计选型,最后采用PRO/E对分选机进行三维设计.     

表皮生长因子受体Ⅲ型变异体（EGFRvⅢ）多克隆抗体的制备及特异性

为了制备针对EGFRvⅢ的特异性多克隆抗体,在实验中利用耦联了血蓝蛋白的EGFRvⅢ特异性的PEP3合成短肽进行动物免疫,制备抗血清;构建了pET30a／E33XI原核表达载体,表达和纯化了融合蛋白His-E33（EGFRvⅢ的部分胞外区）;以此融合蛋白作为抗原制备了抗体纯化柱,通过柱上纯化的方法从抗血清中提取针对EGFRvⅢ的特异性抗体．利用U87、U251、HeLa和HEK-293细胞进行免疫组化实验来检验抗体的特异性．     

线性0—1规划模型的排序解法

针对0－1规划模型提出了一种新的解法,即排序法。它利用目标函数变量系数绝对值大小的相对关系,对无约束条件解进行排序,在最小解集中寻找最优解,以加快收敛速度。     

An optimal data-splitting algorithm for aircraft scheduling on a single runway to maximize throughput

In this research, we present a data-splitting algorithm to optimally solve the aircraft sequencing problem (ASP) on a single runway under both segregated and mixed-mode of operation. This problem is formulated as a 0–1 mixed-integer program (MIP), taking into account several realistic constraints, including safety separation standards, wide time-windows, and constrained position shifting, with the objective of maximizing the total throughput. Varied scenarios of large scale realistic instances of this problem, which is NP-hard in general, are computationally difficult to solve with the direct use of commercial solver as well as existing state-of-the-art dynamic programming method. The design of the algorithm is based on a recently introduced data-splitting algorithm which uses the divide-and-conquer paradigm, wherein the given set of flights is divided into several disjoint subsets, each of which is optimized using 0–1 MIP while ensuring the optimality of the entire set. Computational results show that the difficult instances can be solved in real-time and the solution is efficient in comparison to the commercial solver and dynamic programming, using both sequential, as well as parallel, implementation of this pleasingly parallel algorithm.     

Investigation of tailpipe and evaporative emissions from China IV and Tier 2 passenger vehicles with different gasolines

The limited understanding of vehicular emissions in China, especially evaporative emissions, is one obstacle to establishing tighter standards. To evaluate tailpipe and evaporative emissions, two typical China IV vehicles and one Tier 2 vehicle with an onboard refuelling vapour recovery (ORVR) system were selected and tested. One of the China IV vehicles was fuelled with gasoline, E10 and M15, respectively, to investigate the effect of fuel properties on vehicular emissions. For each vehicle, cold-start tailpipe emission tests were conducted first, followed by an evaporation test. Based on the emission factors and real-world vehicle activity data, the annual tailpipe and evaporative hydrocarbon (HC) emissions of each vehicle were calculated and compared. The results show that E10 and M15 significantly reduced the tailpipe CO and particle number (PN) emissions but seriously aggravated the NOx emissions, especially for M15. The hot soak losses (HSLs) and diurnal breathing losses (DBLs) were slightly impacted by the fuel properties. The annual evaporative emissions with E10 and M15 were higher than that with gasoline. The ORVR system effectively controlled the evaporative emissions, especially for DBLs. Evaporative emissions from the China IV vehicles were 1.1–1.4 times the tailpipe HC emissions. Additionally, the evaporative emission factors of the China IV vehicles were almost 50% lower than the standard (2.0 g/test), whereas their annual evaporative emissions were almost 1.8–2.8 times higher than those from the Tier 2 vehicle. Therefore, controlling evaporative emissions currently remains a great need in China, and the ORVR might be a recommended evaporative control technology.     

刚构桥0#块混凝土水化热温度场改值模拟分析

文章结合罗天乐连续刚构桥施工实例,运用有限元模型对该桥0#块混凝土浇筑施工过程中的温度场变化情况进行了数值模拟分析。结果表明,0#块混凝土内部最高温度及最大内外温差计算值与实测值吻合较好。     

GML3.0及其在空间数据建模中的研究

GML的提出为解决空间数据共享提供了一个契机。地理标记语言GML(Geography Markup language)是由OGC开发的一套基于XML的数据编码规则,主要用于地理信息的建模、存储和传输。本文首先简要介绍了GML3．0新增的内容、功能以及基本的数据模型。然后以构建旅游地理信息系统的空间模型为例,论述了GML空间数据建模的步骤。