Results 41 to 50 of about 31,188 (236)
Jianzhu Gangjiegou Jinzhan, 2008 本文对中、日、欧州及美国地震规范地震力计算的结构影响系数的构成进行了分析,认为,美国的结构影响系数中包括了材料的强屈比、超静定结构体系的超强系数以及延性系数;而欧洲的结构影响系数包含了延性系数,对于延性好的结构还允许包含结构体系的超强系数;日本仅包含延性系数;我国也是仅包含延性系数。由于日本采用允许应力设计,还有一个1.4的安全系数,因此比较起来,日本的地震力最大。从结构影响系数的构成看结构在地震作用下产生塑性变形的深度,按照美国规范设计的结构塑性变形要求最高,欧洲次之,我国再次之 ...
童根树, 赵永峰
doaj
Integrative Conservation, Volume 3, Issue 4, Page 398-409, December 2024.Understanding the potential impacts of projected climate change scenarios on critically endangered species is critical to guide effective conservation planning. Species distribution modelling techniques such as MaxEnt are increasingly becoming important tools for predicting habitat shifts in response to projected climate change scenarios.
Mark Zvidzai +4 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan本文设计制作了4个H型钢梁试件，通过拟静力试验得到不同腹板高厚比以及不同钢种组合下钢梁的破坏形态、滞回曲线、骨架曲线以及延性等，并评估了试件的滞回性能。随后利用有限元软件ABAQUS进行模拟验证，通过参数分析进一步补充了不同腹板高厚比和不同钢种组合对钢梁滞回性能的影响。结果表明：随着腹板高厚比的减小，钢梁的延性和滞回耗能能力均有所提高，且增大腹板厚度对钢梁延性的提高程度大于对钢梁极限承载力的提高程度；相比同钢种钢梁，多钢种混用钢梁的极限承载力提高了17.4%、延性降低5.6 ...
朱爱珠 +4 more
doaj +2 more sources
World Medical &Health Policy, Volume 16, Issue 4, Page 577-599, December 2024.Abstract Most Americans rely on managed care networks and provider directories to access care. Little is known about how patients experience navigating directories, how it affects their lives, and whether Americans support federal action on the issue. We fielded a large, and demographically diverse survey of US adults (N = 10,739) from January to April
Simon F. Haeder, Wendy Yi Xu
wiley +1 more source
A 3D modelling approach to measuring structural characteristics of bird nest interiors
Methods in Ecology and Evolution, Volume 15, Issue 12, Page 2226-2233, December 2024.Abstract Nests are considered extended phenotypes of animals with potentially serious fitness consequences for the survival of offspring. Therefore, nest characteristics may contain valuable information about the underlying ecological and evolutionary mechanisms shaping animal reproduction.
Jing‐Chia Guo +2 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2004 本文通过对8根钢管高强混凝土压弯构件试件在恒定轴力和水平周期反复荷载作用下抗震性能的试验研究,阐述了混凝土强度、轴压比和含钢量对钢管高强混凝土压弯构件延性性能的影响,由试验结果分析了影响构件延性性能的主要原因及因素,并提出建议。
伊新富, 方鸿强
doaj
Duration in power and happiness in the world
Politics &Policy, Volume 52, Issue 6, Page 1331-1352, December 2024.Abstract This article examines the effect of leader longevity in power on world happiness. To make the assessment, a sample composed of 135 countries observed over the period 2006 to 2018 was constituted. The results obtained from OLS estimates show that longevity in power reduces individual happiness. Furthermore, the negative effect is more amplified
Désiré Avom +4 more
wiley +1 more source
Guangtongxin yanjiu, 2012 为分析融合网络中聚合业务的端到端时延性能,提出一种基于聚合流的融合网络端到端统计时延界的新算法。该算法利用MGF（矩母函数）重新表征了网络端到端时延界的MGF形式的概率模型。数值分析结果表明了该算法的有效性和优越性,该算法很大程度上提高了独立统计复用,对融合网络性能评价具有参考意义。
赵一A, 张中荃
doaj
The enigmatic life history of the bamboo explained as a strategy to arrest succession
Ecological Monographs, Volume 94, Issue 4, November 2024.Abstract Bamboos are perennial woody grasses that display an enigmatic mix of traits. Bamboo is highly shade intolerant like early‐successional trees. Without secondary xylem, bamboos cannot continue to grow once they reach a maximum height or replace xylem damaged by hydraulic stress and must instead replace each stem after a few years using ...
Aiyu Zheng, Stephen W. Pacala
wiley +1 more source