5000m~3拱顶油罐失稳原因分析

为了保证油罐使用中的安全性,油罐不仅要具有足够的强度,而且还应该具有可靠的稳定性。应用外压失稳理论分析某厂５０００ｍ３拱顶油罐失稳原因,结果表明,该油罐缺乏足够的稳定性设计;为了保证油罐的稳定性,油罐设计必须符合实际工况条件,油罐施工建造必须保证质量标准。     

开敞式叉筒网壳风场数值模拟与受力分析

针对国家现行<建筑结构荷载规范>缺乏复杂形体结构净风压体型系数的相关规范的问题,应用标准k-ε紊流封闭模型,采用数值风洞技术对开敞式叉筒网壳在多角度风场作用下结构表面的风压分布进行了数值模拟,获得了该类网壳的净风压体型系数.研究表明采用数值风洞技术对复杂形体结构的流场进行计算机数值模拟的方法是可行的,这为风压分布及大小取值提供了一种非实验性的、低成本的取值方法.力学分析结果表明,风对开敞式叉筒网壳的最大负压主要集中在脊线附近的边缘部位,脊线附近边缘以及谷线交叉拱是结构设计的重点.     

Thermal performance and embodied energy analysis of a passive house – Case study of vault roof mud-house in India

This paper investigates thermal performance of an existing eco-friendly and low embodied energy vault roof passive house (or mud-house) located at Solar Energy Park of IIT Delhi, New Delhi (India). Based on embodied energy analysis, the energy payback time for the mud-house was determined as 18 years. The embodied energy per unit floor area of R.C.C. building (3702.3 MJ/m²) is quiet high as compared to the mud-house (2298.8 MJ/m²). The mud-house has three rooms with inverted U-shape roof and remaining three rooms with dome shape roof. A thermal model of the house consisting of six interconnected rooms was developed based on energy balance equations which were solved by using fourth order Runge Kutta numerical method. The predicted six room air temperatures were found in good agreement with the experimental observed data on hourly basis in each month for one year. The annual heating and cooling energy saving potential of the mud-house was determined as 1481 kW h/year and 1813 kW h/year respectively for New Delhi composite climate. The total mitigation of CO₂ emissions due to both heating and cooling energy saving potential was determined as 5.2 metric tons/year. The annual carbon credit potential of mud-house was determined as € 52/year. Similar results were obtained for the different climatic locations in India.     

低压拱顶罐安全技术探讨及应用

探讨了低压立式拱顶罐设计及应用中存在的问题及应具备的安全技术要求。并证明 有效安全技术措施对于保证低压立式拱顶罐的安全运行和提高经济效益具有积极的作用。     

吐鲁番民居屋顶平拱流变初探 #

吐鲁番传统民居中存在两种屋顶结构类型——密梁平顶式与发券拱顶式,对于这二者在该地区出现的前后顺序、时间、与其他地区的渊源关系等问题,一直是历史谜题。基于建筑结构与形式的演变规律对其进行推测,辅以洋海墓地与交河故城的考古发掘,认为该地密梁平顶式民居先于发券拱顶式民居;以对该地遗迹的考古发掘为线索,结合佛教传播等相关史实,提出以技术需求的视角解释西域拱顶的应用历史晚于汉地,并指出拱顶在该地的应用经历了事鬼神与世俗化两个阶段。     

一种改进的指纹Fuzzy Vault加密方案

为了克服传统指纹Fuzzy Vault算法在应用上的不足,提出了一种改进的Fuzzy Vault算法。主要采用一种新的多项式构造函数的方法来实现待保护密钥和指纹细节特征点的绑定,进而解决了传统Fuzzy Vault算法中密钥长度决定解码时需要匹配细节点个数的问题。实验结果表明,此方法进一步增强了算法的安全性和灵活性。     

Entrepreneurship in Architectural Robotics: The Simultaneity of Craft,Economics and Design

What do Odico Formwork Robotics, RoboFold, Machineous, ROB Technologies and GREYSHED share in common? They are all architectural robotics startups. Jelle Feringa , Chief Technology Officer at Odico, places the phenomenon of the architectural robotics entrepreneur in a historical and cultural context while highlighting the very practical role startups are poised to play in bridging the gap between academic research and industry, by providing the building industry with much needed new software tools.     

液化气低温储罐及其施工技术

针对液化气需要低温储存的特点，介绍几种液化气低温储罐的结构形式，并对我国目前制造和使用的钢制双壁吊顶低温储罐的施工步骤和密封、平衡、气举等主要技术措施予以总结报道。     

基于Chaff Matrix的可撤销声纹模板设计

基于模糊穹的特征保护方法存在敌手冒充和空间自由度减少的问题。为此,提出一种基于伪矩阵(Chaff Matrix)的可撤销声纹模板设计方法。通过原始特征矢量的构成元素产生伪点,根据定位矩阵将伪点插入原始特征,且在欧氏距离准则下,插入前后特征矢量与模板之间距离的变化量相同,从而保证系统识别率,实现特征保护。实验结果验证了该方法的正确性。     

生物特征密码技术综述

生物特征密码技术,即融合生物特征识别技术与密码技术的新兴技术,主要体现为基于生物特征识别技术的密钥保护技术与密钥生成技术。生物特征密码技术不仅可以安全保护用户的生物特征信息免遭泄露的风险,更重要的是可以解决各种对象实体的数字身份认证与私密信息的加密保护问题。本文综述了自1996年第一个利用指纹特征的密钥生成方案及2012年经典模糊金库提出以来主要的密钥生成技术研究工作,剖析了这些方案的基本结构及性能优劣,并探讨了生物特征密码技术的未来研究思路。