兰州红楼时代广场超限高层性能化抗震设计

兰州红楼时代广场屋顶结构标高245.60m,是目前西北地区第一高楼,地处兰州市中心,设防烈度为8度(0.20g),地震安全性评价的设防烈度接近8度(0.30g)。项目除高度超限外,还存在其他多项超限内容,如利用避难层设置2道加强层,裙楼局部利用转换桁架实现抽柱转换,塔楼顶部和裙楼入口处形成斜切面,核心筒剪力墙从层55开始内收等。进行了基于性能的抗震设计,根据构件的重要性分别提出不同的性能设计目标,并采取相应抗震加强措施。通过不同程序分别进行了中震弹性和不屈服计算、以及大震弹塑性分析。分析表明,所提出的各种性能化目标均得到实现,性能化抗震设计和采用的抗震措施能满足结构"小震不坏、中震可修、大震不倒"的抗震设防要求。     

Multi‐Objective Optimization of Interior Ballistic Performance Using NSGA‐II

This paper investigates an interior ballistic design with equal and unequal web thicknesses of seven‐perforation propellant grains using optimization methods. In order to reveal the influence of the web thickness of the propellant grains on the overall interior ballistic performance, burning seven‐perforation propellant grains with both equal and unequal web thickness is modeled. A currently popular evolution algorithm (EA) is used to compare two charge shapes, and to seek which one could achieve the optimal ballistic performance. Complete optimization of the interior ballistic performance is a complex process in view of the conflicting objectives to be achieved and a solution to such problems is sought by converting them into a single composite objective and using many tedious measurements. In this paper, a true multi‐objective optimization of the interior ballistic charging design is carried out by considering three objectives simultaneously. The non‐dominated sorting genetic algorithm version II (NSGA‐II) is used to solve this multi‐objective optimization problem (MOP). In order to check its implementation, both the conventional optimization algorithm‐hill climbing method (HCM) and NSGA‐II are used to solve the same single objective problem. The NSGA‐II used to capture the full Pareto‐optimal front is capable of identifying the trade‐off among the conflicting objectives thereby providing alternative useful designs for a designer. Furthermore, for seven‐perforation propellant grains, the results of using equal web thickness are compared with those of unequal web thickness, and it is shown that the two charge shapes produce no distinct difference in the interior ballistic performance.     

A dual objective global optimization algorithm based on adaptive weighted hybrid surrogate model for the hydrogen fuel utilization in hydrogen fuel cell vehicle

Current engineering optimizations mainly use surrogate models (SMs) to approximate complex black-box problems. However, SMs with different approximate characteristics may make the designers unable to accurately judge which type of SMs is more suitable for the actual optimization design. A reasonable combination of different SMs might be one of the solutions. To this end, a global optimization algorithm based on an adaptive weighted hybrid surrogate model (GOA-AWHS) is proposed. In each iteration, a hybrid model based on kriging and RBF is first constructed by adaptively selecting weight coefficients. Next, two objectives consisting of predicted objective, root mean square error and distance parameters are optimized to generate the Pareto frontier. Finally, further selection of data points on the Pareto front yields multiple promising optimal solutions. A series of standard numerical functions and hydrogen fuel utilization in hydrogen fuel cell vehicles are tested to demonstrate the effectiveness and robustness of the GOA-AWHS method.     

深圳证交所大厦弹塑性动力分析

深圳证交所大厦的结构总高度为236.95m,为超B级高度的超限高层建筑,存在侧向刚度不规则、竖向体型不规则和抗侧力构件不连续等3项结构不规则。为评估结构在罕遇地震作用下的性能,基于ABAQUS程序和混凝土塑性损伤模型,利用自行开发的前处理转换程序和材料用户子程序,对结构进行弹塑性动力时程分析,给出了在罕遇地震场地波和ElCentro波作用下结构变形、关键构件的塑性损伤以及结构整体弹塑性反应。结果表明:采取抗震加强措施后的结构能满足"大震不倒"的抗震性能要求。     

灰度图像彩色化的效果评价研究

灰度图像彩色化的效果评价是目前图像彩色融合和增强急需解决的问题之一。从彩色化图像与原灰度图像比较和彩色化图像之间比较两方面对灰度图像的彩色化效果评价进行研究,提出了相应的主观评价方法和客观评价参数。     

基于改进型像素标记算法的目标定位

提出新的像素标记算法,与以前的像素标记算法不同,该算法首先对目标点进行分类,然后根据不同的标记规则对不同的目标点进行标记。该算法不仅在算法复杂度上有所减少,只需一次扫描就能完成目标的描述,而且能够得到目标的面积、重心和边界坐标等信息。该算法已经应用于带钢表面缺陷检测,具有快速、准确等特点。     

基于属性扩展图的聚类算法研究

提出一种新的图聚类算法,结合结点的结构及属性特性,使用统一的随机移动距离计算结点间的相似度,在邻接随机移动距离矩阵的基础上进行聚类.实验结果表明,基于属性扩展图的聚类算法在图拓扑结构的基础上,充分考虑了各个结点所拥有的属性特点,得到的聚类结果将更好的切合实际的应用.     

基于复杂地质目标的地震采集技术综述

随着勘探开发程度的不断提高,勘探目标已经以复式隐蔽油气藏和复杂地质目标为主,在某些地区进行勘探,传统的地震采集技术已经不能满足实际应用的需要。近几年,地震采集装备和数值模拟技术得到快速发展,地震采集技术的发展集中体现在提高地震数据分辨率和改善深层数据品质方面,而面向复杂地质目标的地震采集技术是其中的关键技术。本文立足于当今地震采集技术的发展趋势,介绍了基于复杂地质目标的地震采集技术的发展以及应用实例。     

基于近似模型管理的微小卫星结构多目标优化设计

针对某型号微小卫星结构多目标优化的特性,在基于信赖域近似模型管理的基础上,提出了一种新型的近似模型管理框架。选取正交试验法和Kriging近似法用于构建近似模型,选取基于拥挤距离的粒子群多目标优化算法作为核心算法,并通过最大最小距离策略来保证信赖度计算的准确性与合理性,从而确保获取与高精度模型一致的非劣解集。所选的五组优化结果显示,卫星结构质量均有不同程度的减小, 最大减幅达到14.1%,同时整星前三阶固有频率较优化前明显提高。该近似模型管理框架在微小卫星结构多目标优化设计中的成功运用验证了其有效性及合理性,对于复杂工程多目标优化问题具有一定的工程应用价值。       

起毛起球表征技术的研究进展与问题

针对起毛起球机制及问题,本文结合现有的起球方法和表征技术,介绍了常用的三种织物起毛起球起因及其主观评价方法、图像处理织物表面毛球的客观表征和神经网络预测起球的虚拟表征方法;对前人在该领域的研究工作进行回顾,提出起毛起球机制研究和表征研究中只着重于起球成因的解释并在机制上进行解决和表征而忽略了对起毛机制及表征的深入探究,以强调研究起毛起球本质机制的重要,提出了因机制研究不足导致的各种表征技术存在的缺憾,揭示了表征技术对明晰起毛起球的机制的重要性,将有利于对织物的起毛起球机制进行本质表达。