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Integrative Conservation, Volume 4, Issue 1, Page 85-94, March 2025.Chromolaena odorata and Ageratina adenophora are invasive species in Southern Yunnan, China; they have very differing, yet overlapping, climate niches. Both invaders produce a large number of small pappus‐bearing achenes every year. They grow in, and their seeds are dispersed to, both suitable and marginal habitats.
Bin Wen +5 more
wiley +1 more source
Uncovering Xi Jinping's Policy Agenda: Text As Data Approach
The Developing Economies, Volume 63, Issue 1, Page 9-46, March 2025.How many agendas has Xi Jinping put forth and promoted since taking office in 2012, and what are the types of agendas? How much of political attention has each agenda received, and how has the allocation of attention changed over time? We utilize a dataset of presidential statements, speeches, and reports from 2012 to 2022 and employed automated text ...
Jaehwan Lim, Asei Ito, Hongyong Zhang
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2005 扇形焊接开孔为进行梁翼板全渗透开槽焊接时所需之工作孔。然而,实尺寸梁柱接头试验证实,传统梁腹板锁螺栓及梁翼板全渗透焊接之钢构造梁柱接头,常于扇形开孔处发生突然性之脆性破坏。本研究采用非线性有限元素分析方法,探讨扇形焊接开孔于钢骨梁柱接头耐震行为上之影响,包括扇形开孔几何形状对接头区力学行为之影响。分析结果显示,平顺接至梁翼板之扇形开孔能将最大塑性应变之发生位置移离扇形开孔根部,减少因几何形状不连续所造成之应力集中现象,降低局部区域之韧性需求;无扇形开孔之梁柱接头可避免有扇形开孔之缺陷 ...
陈诚直, 林群洲
doaj
The Economic History Review, Volume 77, Issue 3, Page 796-822, August 2024.Abstract This article studies Rotating Savings and Credit Associations (ROSCAs) in late imperial and Republican‐era Shanxi province, China, from the eighteenth to the twentieth centuries. It investigates how communal finance fostered pre‐industrial economic growth and commercial activity. Drawing on previously unused, original materials from historical
Matthew Lowenstein
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Jianzhu Gangjiegou Jinzhan装配式槽钢腹板开孔耗能支撑由中心支撑斜杆两端设置的腹板开孔槽钢构成，开孔槽钢与H型钢支撑之间采用螺栓连接，可避免中心支撑斜杆受压失稳。为研究该支撑的滞回性能，设计了3根开孔形式不同的装配式槽钢腹板开孔耗能支撑试件，对试件开展了低周往复加载试验，并进行了有限元模拟分析。研究结果表明：在轴力作用下，装配式槽钢开孔耗能支撑主要依靠端部槽钢开孔腹板的孔间板件屈服耗能，整个加载过程中支撑主体H型钢未发生失稳；加载过程中螺栓出现了滑移，滞回曲线有不同程度的捏拢；试验中腹板开椭圆孔的试件耗能能力最强 ...
徐奔, 赵宝成, 顾晨姣
doaj +2 more sources
Failure behavior analysis of high stiffener web height I-girders of cruise ships considering initial welding defects [PDF]
ObjectiveHigh stiffener web height I-girders on large cruise ships are made of thin welded plates, which lead to noticeable weld distortion and stresses during manufacturing, and can affect the load-bearing characteristics of the structure. Therefore, in
Chen CHEN +4 more
core +1 more source
Experimental study of high moisture corn dewatering in rotating air drying barn [PDF]
, 2020 Academy of national food and strategic reserves administration designed a rotating air drying barn. The research on dewatering technology of high-moisture corn was carried out in this paper by using the self-developed rotating air drying barn.
CAO Yang +5 more
core +1 more source
, 1992 提供了一种在大口径激波管中降低2区气流雷诺数的方法。采用该方法雷诺数可由通常的10~6～10~7量级降至工10~5量级。实验结果表明采用此方法后2区流场未受明显扰动。给出了驱动压比 P_41与主激波马赫数 ...
俞鸿儒 +3 more
core
Jianzhu Gangjiegou Jinzhan为了对比不同开孔形式对腹板开孔钢梁抗冲击性能的影响，比较了腹板开六边形与圆形孔的钢梁在孔间距和孔高不同时的等效抗弯刚度，开展了落锤冲击试验和有限元分析。主要对开孔形式、冲击能量、孔间距、孔高和冲击作用位置进行参数分析。在试验过程中采集落锤冲击力、位移以及孔周围应变。结果表明：六边形腹板开孔钢梁相较于圆形腹板开孔钢梁在落锤冲击作用下产生变形更大；圆形腹板开孔钢梁的冲击力平台值更大，抵抗冲击作用的能力更强，对冲击的耗能能力更强；圆形腹板开孔钢梁产生的最大位移为六边形腹板开孔钢梁的86.49 ...
陈华艳 +7 more
doaj +2 more sources
, 2018 以碳氢燃料为冷却介质的冲击射流冷却在高超声速飞行器及发动机热防护领域有着重要的应用前景。与传统的冲击射流冷却介质水、空气有所不同,碳氢燃料具有复杂的热物性,其冲击射流流场与传热特性将发生显著变化,需要深入研究。本文采用雷诺平均方法结合SST k-ω湍流模型数值研究了相同流量条件下,冲击孔板不同开孔率的航空煤油冲击冷却流动与传热特性。本文的研究表明,煤油通过冲击孔形成高速射流冲击到冷却面,在冲击冷却面产生了很强的换热效果,换热系数由射流滞止区向周围逐渐减。同时,由于多股冲击射流之间的相互作用 ...
仲峰泉 +3 more
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