升船机齿条、螺母柱及二期埋件施工质量控制

针对向家坝升船机齿条、螺母柱及二期埋件施工程序复杂、安装精度要求高等技术难点,经对其施工工艺进行研究分析后,提出了先安装低高程的齿条、螺母柱及二期埋件,待船厢结构、设备及平衡重系统完成安装并对塔柱按设计时间实施加载后,再进行高高程齿条、螺母柱及二期埋件安装的工序流程及质量控制措施。同时采用摄影测量对首节螺母柱的相对位置进行校验。最终的测量验收数据表明,所提施工方案及质量控制措施是可行的,可为类似工程施工提供借鉴。     

T形柱正反向受剪承载力和变形能力特性研究

由于T形柱特殊的截面形式,正反向受剪时将分别处于腹板受压、翼缘受拉和腹板受拉、翼缘受压两种状态,故其正反向受剪承载力和变形能力与十字形柱相比差异较大。通过对国内T形柱受剪承载力试验进行分析,探讨了T形截面柱正反向受剪承载力特性,并对某一T形柱进行低周反复荷载试验,分析了低剪跨比状态下T形柱正反向加载破坏特征、承载能力和变形能力特性。研究表明,T形柱截面不规则,当狭义剪跨比小于3.0时,正反两个方向受剪承载能力和变形能力存在显著差异,两个方向的抗震性能亦存在差异,腹板受压时,柱脚腹板混凝土破坏严重,降低了异形柱的截面刚度和承载力,成为异形柱结构的薄弱部位。     

土中不耦合柱状装药的外部作用爆腔分析

基于现场爆破试验、爆炸应力波理论和爆生气体等熵方程,分析了土中不耦合垂直柱状药包外部作用的爆腔特性,将爆腔分为柱状空腔和半椭球腔两部分,并推演了柱状空腔半径和半椭球腔高度的理论计算公式。通过进行现场爆破试验和理论计算的对比分析,表明:柱状空腔半径比半椭球腔高度大,柱状空腔半径为8.5～15.3倍炮孔半径,半椭球腔高度为7.5～12.1倍炮孔半径。理论计算值与试验值较吻合,理论计算的柱状空腔半径的误差范围是5.2%～20.6%,理论计算的半椭球腔高度误差范围为2.0%～24.8%。同时表明:不耦合装药时药包周围空气间隙的大小对柱状空腔半径影响较大。     

基于子空间方法的精馏塔系统辨识建模研究

子空间辨识方法作为一种有效的针对多输入-多输出系统(MIMO)的辨识建模方法近年来受到广泛的重视.目前主要采用的子空间辨识算法只能适用于白噪声环境,而实际的工业现场数据很多是受到较大有色噪声干扰的.针对问题采用了一种新的子空间辨识算法,利用马尔可夫参数用于处理随机性部分,同时引入辅助变量用以去除噪声的干扰,能够适用于存在较大有色噪声干扰情况下的辨识建模,并可得到对象的无偏模型,建模的精度优于通常所采用的子空间辨识算法.通过对精馏塔仿真模型的辨识结果证明了该方法的可行性和有效性,以及在实际工业过程对象建模中良好的应用前景.     

Soft sensing modelling based on optimal selection of secondary variables and its application

The composition of the distillation column is a very important quality value in refineries, unfortunately, few hardware sensors are available on-line to measure the distillation compositions. In this paper, a novel method using sensitivity matrix analysis and kernel ridge regression （KRR） to implement on-line soft sensing of distillation compositions is proposed. In this approach, the sensitivity matrix analysis is presented to select the most suitable secondary variables to be used as the soft sensor＇s input. The KRR is used to build the composition soft sensor. Application to a simulated distillation column demonstrates the effectiveness of the method.     

The lateral load-deformation response of RC walls with a consideration of the height–length ratio

Reinforced concrete (RC) walls play an important role in resisting earthquakes, so understanding the lateral load-deformation response of an RC wall subjected to an axial load, shear, and moment is essential to nonlinear structural analysis. In this study, the moment-bending deformation response of an RC wall under an axial load and moment is obtained from moment–curvature analysis using the wall’s proper plastic hinge length. Furthermore, modified compression-field theory, adjusted according to the height–length ratio of the wall, is used to calculate the shear–shear deformation response of the wall under an axial load and shear. By integrating the moment-bending deformation and the shear–shear deformation responses, the lateral load-deformation response of the RC wall under axial load–moment–shear interaction can be reasonably determined. To confirm the reliability of the proposed method, experimental results for 67 RC walls are compared with analysis results from the proposed method. The statistical results show that the proposed method accurately predicts the lateral ultimate load but somewhat underestimates the lateral ultimate deformation. Finally, this paper gives an example using an equivalent column to simulate an RC wall using SAP2000 pushover analysis.     

不同因素影响下混凝土立柱爆破效果的模型试验研究

钢筋混凝土建（构）筑物爆破拆除过程中,混凝土立柱最终的破碎效果不仅与炸药单耗、孔网参数等有关,还与立柱的受力状态有关。为研究截面应力和单位面积炸药量对不同强度混凝土立柱破碎效果的影响,利用自主研制的力学试验系统进行了15组爆破试验,从碎块筛分和分形维数两方面分析爆破效果。结果表明:对于相同强度的试件,截面应力一定时,随着单位面积炸药量的增加,分形维数整体上不断递增;但单位面积炸药量超过0.18 kg/m²后,增势有所放缓,截面应力为2 MPa和4 MPa的立柱趋势变化最为明显。单位面积炸药量一定时,随着截面应力的增加,碎块分形维数不断增大,当单位面积炸药量小于0.15 kg/m²时,0~2 MPa之间的截面应力增加会对分形维数有一定的抑制作用;当单位面积炸药量大于0.15 kg/m²时,截面应力的增加对分形维数起到促进作用。可为拆除爆破中的参数设计及优化提供理论依据,达到了控制爆破危害、改善爆破效果的目的。     

三相反应器的气含率与液速分布和数值模拟

研究了一定操作条件下的气液固三相鼓泡床反应器的气含率和液体轴向速度分布,讨论了气、液表观速度对气含率和液体轴向速度分布的影响,比较了三相与两相鼓泡床中气含率和液体轴向速度分布,用拟两相的双流体模型计算了三相鼓泡床中的气含率和液体轴向速度．结果表明,模拟结果与实验结果一致．     

《交换空间》栏目引导新的家装理念浅析

本文通过表述传播学五大要素在《交换空间》栏目中的体现,主要介绍了家装从规划设计到具体实施的整个过程在《交换空间》栏目中的体现,分析了《交换空间》作为一种具体的可实施性强的节目对家庭装饰装修理念新的诠释。     

Hypercolumn-array based image representation and its application to shape-based object detection

Biological and psychological evidence increasingly reveals that high-level geometrical and topological features are the keys to shape-based object recognition in the brain. Attracted by the excellent performance of neural visual systems, we simulate the mechanism of hypercolumns in the mammalian cortical area V1 that selectively responds to oriented bar stimuli. We design an orderly-arranged hypercolumn array to extract and represent linear or near-linear stimuli in an image. Each unit of this array covers stimuli of various orientations in a small area, and multiple units together produce a low-dimensional vector to describe shape. Based on the neighborhood of units in the array, we construct a graph whose node represents a short line segment with a certain position and slope. Therefore, a contour segment in the image can be represented with a route in this graph. The graph converts an image, comprised of typically unstructured raw data, into structured and semantic-enriched data. We search along the routes in the graph and compare them with a shape template for object detection. The graph greatly upgrades the level of image representation, remarkably reduces the load of combinations, significantly improves the efficiency of object searching, and facilitates the intervening of high-level knowledge. This work provides a systematic infrastructure for shape-based object recognition.