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Beyond Evidence: How Framing Shapes Public Health Policies During Health Crises
Policy Studies Journal, Volume 54, Issue 4, November 2026.ABSTRACT Does the level of evidence that accompanies policy action depend on how a problem is framed, and on who frames it? This article examines these questions in the context of health crises. Bridging sociological and equivalence framing theories, it treats frames as preexisting interpretive schemes shared within communities of actors, whose ...
Antoine Claude Lemor, Eric Montpetit
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, 2010 【目的】研究不同生境的多枝树柳种群空间分布点格局。多枝柽柳(Tamarix ramosissima)种群在自然界中主要有4种生境分布类型:风沙土生境类型、草甸土生境类型、吐加依土生境类型和盐土生境类型。【方法】采用点格局分析法分析了不同生境中多枝柽柳在不同尺度下的空间分布格局。【结果】①风沙土生境类型,尺度2~7 m以内,其为集群分布,当尺度大于7 m时,则为随机分布;②草甸土生境类型和吐加依土生境类型的柽柳种群,在所有的尺度(t)下,均显著地偏离集群分布,呈随机分布;③盐土生境类型,尺度6~7 m以内,
陈金星, 尹林克
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托卡马克中凯尔文-亥姆霍尔茨不稳定性与密度分布及速度分布的关系 [PDF]
, 1985 近年来,在托卡马克装置实验中观察到等离子体环的密度及环向速度沿半径都有变化。当反平行中性束注入时,密度分布对应空洞型温度(即中心温度低而外侧高),等离子体的稳定性变坏。本文对密变分布和速度分布对等离子体环的凯尔文-亥姆霍尔茨稳定性的影响分别进行了研究,得出,在托卡马克实验参数范围内,密度沿半径的分布会使凯尔文-亥姆霍尔茨稳定性变坏 ...
唐福林
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Gaoya dianqi, 2003 利用表面电荷法对绝缘子表面的电压分布和场强进行了计算,研究了影响电压分布的某些因素,如均压环、伞裙对电压分布的影响。计算表明,合成绝缘子的电压分布特性与瓷质绝缘子有很大不同,其电压分布非常不均匀,高压端承受了更高的电压。伞裙和均压环均能改善电压、场强分布,但合成绝缘子均压环对电压分布均匀性的改善不如瓷质悬式绝缘子。
郭效金
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Asymptotic distribution of the product of trimmed sums(一类截断部分和乘积的渐近正态性)
Zhejiang Daxue xuebao. Lixue ban, 2007 对于取值为正的独立同分布且平方可积的随机变量X1，X2，…且有连续的分布函数，令Mn = max{X1，X2, …，Xn}，对某固定常数a>0，令，截断和Tn（a）= Sn — Sn(a），在X的分布满足中尾分布的条件时，截断和Tn(a)的乘积为渐近对数正态.
ZOUHai-lian(邹海连) +1 more
doaj +1 more source
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT To improve the strength–toughness balance of IN718, and alleviate the brittleness commonly associated with refractory high‐entropy alloys, this study proposes a novel strategy to fabricate defect‐free IN718/WMoTaNb heterogeneous multiprincipal element alloy coatings via laser‐directed energy deposition.
Zhao Wang +7 more
wiley +1 more source
Local Public Goods Provision in the Post-Agricultural Tax Era in Rural China [PDF]
This paper investigates regional differences in local public goods provision in rural area in the 2000s, using large village sample surveys (CHIP 2002 and 2007 surveys, a survey in Ningxia).
Hiroshi Sato, Sai Ding
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, 2004 本文以尾流振子模型为基础,通过改进Lyong的半经验公式法,研究了张力腿的张力变化以及流场分布对张力腿涡激振动响应的影响.计算结果表明,张力腿的张力改变,使各阶模态的锁频区域分布发生变化,从而改变了结构的涡激振动响应;流场分布的响应计算表明,同样的流场分布对不同阶模态的激励作用的效果不同 ...
王艺, 陈伟民
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Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT The deformation behavior of NiTiNb shape memory alloys is governed by microstructural heterogeneity, specifically the interconnected topology of the β‐Nb phase. The regulatory role of the eutectic structure in load partitioning and the evolution of deformation mechanisms, particularly in high‐Nb systems, has not been clearly understood.
Qingda Zhang +11 more
wiley +1 more source
, 1999 对攀枝花苏铁（Ｃｙｃａｓｐａｎｚｈｉｈｕａｅｎｓｉｓ）种群的地理分布、数量特征、空间分布格局和毁坏历史进行了野外调查和研究。结果表明：攀枝花苏铁种群的自然栖息地是相互隔离和片断化的。已发现的１３个自然种群中，８个分布在金沙江河谷，５个种群分布在金沙江支流河谷；最大的种群位于攀枝花市郊，占有面积约３８０ｋｍ２。７９年以来的商业采挖使８个种群灭绝，种群分布区从３０７００ｋｍ２减少到８８００ｋｍ２，种群占有面积从１１５０ｋｍ２减少到６３０ｋｍ２。３个被研究种群的分布格局为集群分布，以幼苗聚集程度最大 ...
何永华,李朝銮, 李朝銮
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