等效风压法模拟雪荷载的探讨

文章回顾了使用CAESARII系列软件模拟雪荷载的输入方法,并提出了用输入等效风压的方法模拟雪荷载的技巧,使雪荷载的输入比传统方法更加简便快捷。     

可变弹簧选用问题探讨

概述了弹簧支吊架在管道设计中的重要性,介绍了弹簧在管道应力分析中的选用原则及其应用,重点说明了弹簧在CAESARⅡ软件进行管道应力分析时的合理使用方法及冷热态吊零法的优缺点,指出运用CAESARⅡ软件选用弹簧时需要丰富的工程经验。     

超临界空冷供热机组热再热蒸汽管道设计探讨

以呼和浩特热电厂扩建2×350MW超临界空冷供热机组工程热再热蒸汽管道模型为例,使用CAESARⅡ软件比较分析了3种设计方案,讨论了实施冷紧和取消冷紧两种设计方法.使用“U”、“V”型约束调整端口推力、力矩,将各冷紧值合并在一处焊接降低施工量,采用一步计算简化冷紧计算步骤,组合新工况配合支吊架偏装设计弥补程序漏洞.该设...     

等效静力及响应谱法在管道抗震中的应用

运用响应谱分析方法对管道地震的分析提供了一个新的途径。针对管道地震分析中地震谱的定义、工况的设置以及应力合成方法等参数的设定,利用响应谱法及等效静力法分别计算了地震对管系的作用方式及作用结果。计算结果表明：响应谱法由于考虑了动态效应,因此结果要比等效静力法更为全面和准确。响应谱可以作为一种更先进的管道抗震评定方法来取代等效静力法。     

沿坡敷设输气管道应力分析

长距离的输气管道所经过的区域地形复杂多变,在山区丘陵地带一般采用沿坡敷设的方式,由于高低位差的原因,管道受力不均,且大多沿坡敷设的管道都是根据经验参数设计,很容易发生管道失效。为了在前期设计中研究管道的受力分布,校核其是否符合设计规范和安全要求,使用应力分析软件CAESARⅡ对某沿坡敷设管道进行应力分析,研究安装、试压和运行工况下管道的受力情况,得出沿坡敷设方式的安全性较高的结论。分析结果对沿坡敷设管道的设计和施工提供了相应理论依据,具有工程价值和指导意义。     

PDMS与CAESARⅡ接口应用发现的问题及对策

通过对管道模型进行多次测试,针对在使用PSI软件过程中所遇到的问题进行总结、分析,并提出了解决对策,在PDMS-CAESARⅡ接口软件PSI的应用方面具有一定的参考价值。     

General classification of the authenticated encryption schemes for the CAESAR competition

An authenticated encryption scheme is a scheme which provides privacy and integrity by using a secret key. In 2013, CAESAR (the “Competition for Authenticated Encryption: Security, Applicability, and Robustness”) was co-founded by NIST and Dan Bernstein with the aim of finding authenticated encryption schemes that offer advantages over AES-GCM and are suitable for widespread adoption. The first round started with 57 candidates in March 2014; and nine of these first-round candidates were broken and withdrawn from the competition. The remaining 48 candidates went through an intense process of review, analysis and comparison. While the cryptographic community benefits greatly from the manifold different submission designs, their sheer number implies a challenging amount of study. This paper provides an easy-to-grasp overview over functional aspects, security parameters, and robustness offerings by the CAESAR candidates, clustered by their underlying designs (block-cipher-, stream-cipher-, permutation-/sponge-, compression-function-based, dedicated). After intensive review and analysis of all 48 candidates by the community, the CAESAR committee selected only 30 candidates for the second round. The announcement for the third round candidates was made on 15th August 2016 and 15 candidates were chosen for the third round.     

Comparative analyses of anthropometry associated with overweight and obesity: PCA and ICA approaches

This study undertakes to explore the co-varying structure in anthropometric variables that might be affected by the recent surge of overweight and obesity. The increase of overweight and obesity makes the distribution of body dimensions asymmetric by the long tail in distribution (skewness, kurtosis). Principal component analysis (PCA) has been well applied to understand the co-varying body dimensions. However, because PCA decomposes covariance/correlation matrix, the effects of overweight and obesity may not be well captured. Independent component analysis (ICA) is a variant of PCA with the additional assumptions of components being non-Gaussian and independent, in which kurtosis is decomposed. PCA and ICA are applied on the anthropometric data from the North American portion of the Civilian American and European Surface Anthropometry Resource (CAESAR) project. ICA yields more interpretable results by visual inspection than corresponding PCA results. The first independent component (IC 1) is associated with hip/thigh circumferences and chest/waist circumferences and has the largest correlation coefficients with body mass index (BMI). Only the second IC shows the overall size factor that reveals gender difference while principal components 1, 2 and 3 show gender difference. The ICs 3 (torso length) and 4 (arm and leg lengths) are associated with individual differences in body dimensions. The ranges of 38 body dimensions are identified in order to satisfactorily meet the anthropometric variations for both males and females. The ICA gives promise of becoming a valuable tool in the field of ergonomics.     

火电厂汽水管道弹簧计算选择与安装调试一致性分析

分析了目前在火电厂汽水管道应力分析中应用最广的Glif和CAESARⅡ的弹簧计算选择方法,比较了两种软件计算方法的异同点,提出应使弹簧计算选择与安装调试保持一致性,根据不同的弹簧计算选择方式采用相应的安装调试方法,以使弹性支吊架按设计正常工作。     

CAESAR Ⅱ软件中使用GB标准管道材料存在的问题和处理措施

管道应力计算软件CAESAR Ⅱ目前不支持中国电力管道应力计算规范DL/T5366,支持美国动力管道规范ASME B31.1。对在CAESAR Ⅱ软件中使用GB标准管道材料,并采用B31.1规范作应力计算时,存在的安全裕量不足、应力可能超标的问题,分析了其中的原因,给出了在实际工程中处理的措施,保证管道应力安全。