Distortion visualization techniques for 3D coherent sets: A case study of 3D building property units

In the fields of 3D cadastre and 3D property management system, numerous building property objects are adjacent as primary property units assemble into a 3D coherent set. During visualization process of the coherent set, occlusion, obscure, mazy spatial relationships and relative location relationships among the units of the coherent set cause difficulty in observing and understanding the set and its units. Common 3D objects viewing method, such as rotation and navigation obtaining desired visualization effects through adjusting the view angle and position of the camera's field of view, provides weak interactive experience and orientation control for the coherent set because of the neighbour relationships of the 3D objects inside the set. In this paper, a novel method is proposed to solve the prior problems with two basic distortion methods based on “focus + context” theory. The coherent set is first discretized into individual objects and changed them locations according to linear or orthogonal function, while keeping their relative location and dual topological relationships. To maintain both global context awareness (topology and locations) of 3D coherent set and highlight effect of the focus 3D building property object, three evaluation indexes are adopted to assess the corresponding distortion results. A case study based on the real clustered 3D property in Shenzhen was conducted to evaluate the performance of distortion functions, the result shows that the method proposed in this article can not only expand the visual area of focused object and create a clear line of sight (LOS) to the focal object previously obscured, but also maintain verticality and proximity in some degree to facilitate understand the spatial occupation and distribution of whole coherent objects.     

基于模糊修正熵权TOPSIS的战时装备供应链风险评估

针对战时装备供应链的特点,以远程精确打击、敌特后方袭扰和恶劣天气等三个因素为主要风险指标,运用修正的模糊信息熵权对TOPSIS法进行改进,提出了一种新的战时装备供应链风险评估方法。首先利用原始数据产生的模糊信息熵权进行客观赋权,并引入专家因素对权重进行主观修正,利用逼近理想解排序方法进行运算,最后通过实例计算与分析,验证该评估方法简便易行,结论合理,有效降低了指挥员决策的主观随意性。     

低层建筑抗风设计方法比较与研究

土木工程设计中,最有影响和最易引起工程结构失败甚至破坏的首推风荷载.最近几年风灾严重,尤其是风灾导致的低层建筑损失更是惨重.而国际上发达国家的风荷载规范则在不断变化之中,尤其是对轻型钢结构的抗风设计.因此本文有必要对各国低层轻型钢结构抗风设计方法进行研究.本文分别对中国、日本、美国等国家关于抗风设计方法进行比较,并针对风压系数计算一个实例,最后与风洞试验结果进行对照,对中国抗风设计方法进行研究与探讨.     

某超高层建筑的推覆分析

为了研究某一高层建筑在大震作用下的损伤情况,本文采用Midas Building有限元软件对该建筑进行推覆分析.由计算结果知,该结构在大震作用下,最大弹塑性层间位移角为：X向1/219,Y向1/566,均满足规范[1~2]要求的最低标准1/120.根据计算结果,对本工程结构构件进行抗震性能评价,剪力墙、框架柱均未屈服,连梁与框架梁出现塑性铰,但均未达到CP状态[3].结果表明结构能满足抗震性能设计的要求,达到了大震不倒的抗震设防目标.     

基于Blending集成学习模型的电力市场日前出清电价预测

精准的掌握未来电价信息对把握市场的运行状态、支撑市场参与各方进行有效决策、推动市场主体合理优化资源配置具有重要意义。因此基于Blending集成学习机制构建了一种面向于日前电价预测的综合模型。该模型充分考虑电价的高波动性特点,采用Ashin变换,减小了输入数据波动性对预测模型的影响;选取SVM、LightGBM、EWNN、SARIMAX 4种较为成熟的单一电价预测模型作为初级学习器,进而保证了基于Blending集成学习模型的预测精度。选用美国PJM电力市场实际运行数据对上述构建的电价预测模型进行验证,通过对预测结果的对比分析,表明构建的基于Blending 集成学习机制的电价综合预测模型集成了多种传统预测模型的优点,具有较好的准确性与稳定性。     

基于ARM单片机的人身安检装置的设计

针对车站和机场日益突出的乘客人身安全问题,集中研究了乘客的人身检查过程（不考虑行李包的检查）,主要包括金属的探测和身份验证．通过比较和分析我国目前安检技术的缺陷,融合了非接触式射频技术和指纹识别技术,以CortexM3-LPCI768ARM嵌入式微处理器为控制核心,设计出了一种简易的金属探测和身份识别一体化装置．     

高清数字钻孔电视技术研发及其在水电工程中的应用

 钻孔电视是能直观获得钻孔孔壁原状图像的地球物理方法,高清数字钻孔电视技术采用了先进的时间定时器,改进了光学工艺,加入了人-机互动调色功能的高分辨率摄像头,应用了消除电磁场对图像影响的处理技术,使其具有高精度、高分辨率和高保真度等特点。在某水电站坝址和围堰深厚覆盖层可视化研究中,利用高清数字钻孔电视技术,可清晰地获得钻孔孔壁原状图像,从而有效地查明工区的地质情况,为顺利施工提供技术保障,并为建立“数字化电子岩芯库”奠定了坚实的基础。     

多元复合地基法在排水箱涵地基处理中的应用

武钢工业港排水箱涵是武汉市目前最长的压力排水箱涵,内水压力高达12m水柱,且排水不能中断,箱涵沉降伸缩缝一旦漏水,检修及加固均很困难,而且会影响防洪安全。因此,箱涵地基处理的关键是相邻两节箱涵不均匀沉降量的控制。经过方案比选,考虑到经济性,其中一段排水箱涵的地基采用水泥粉喷桩、CFG桩多元复合地基法处理。现箱涵已经建成,交付正常使用。沉降监测结果显示,水泥粉喷桩、CFG桩多元复合地基法在该段箱涵软土地基加固中取得了良好效果。本工程的成功经验可为类似工程提供有价值的参考。     

Stability and antioxidant activity of anthocyanins from purple sweet potato (Ipomoea batatas L. cultivar Eshu No. 8) subjected to simulated in vitro gastrointestinal digestion

The study was aimed to investigate the stability and antioxidant activities of anthocyanins obtained from purple sweet potato via an in vitro digestion system. Three fractions of anthocyanin-rich extracts were obtained via ODS packing column. Anthocyanins and copigment (primary phenolic acids) of fraction 2 were investigated during simulated an in vitro gastrointestinal digestion. Anthocyanins and copigment were recognised by UPLC-LTQ-MS/MS. Besides, anthocyanins were found effectively stable under the acidic gastric digestion conditions. However, the anthocyanins recovery was greatly decreased at around 10% after intestinal digestion. An association between the type, number of acylated group and stability to intestinal digestion was found. Di-acylated anthocyanins possessed higher stability compared with mono-acylated anthocyanins and the stability of acylated group in digestion process followed the order of p-hydroxybenzoyl > feruloyl > caffeoyl. However, there was no much difference in copigment content which was found during digestion process. Moreover, the radical scavenging ability and xanthine oxidase (XO) inhibition showed that the digestion products possessed good biological activities mainly due to its anthocyanin composition.     

基于嵌入压电技术的钢管核心混凝土缺陷检测

钢管混凝土构件核心混凝土缺陷影响到其延性和承载力。利用自制的嵌入式压电功能元,该文提出了基于压电陶瓷应力波测量与分析的核心混凝土缺陷监测方法。通过对比在不同状态的简谐激励下测量信号幅值和扫频激励下小波包能量的差异,定义了基于测量信号幅值和小波包能量的损伤指标。结果表明,利用提出的嵌入式压电技术和定义的损伤指标,有效地识别了钢管混凝土构件的核心混凝土损伤,损伤指标对损伤程度敏感。