Results 51 to 60 of about 1,133,635 (178)

Co‐Teaching in a Virtual Intensive Study Language Programme: Insights From Team Ethnography

open access: yesInternational Journal of Applied Linguistics, EarlyView.
ABSTRACT As virtual study abroad becomes an increasingly important form of international education, little is known about how transnational teaching is organised and sustained across institutions. Using activity theory as an analytical framework and team ethnography as methodology, this study examines a virtual intensive study (VIS) programme delivered
Zhu Hua   +7 more
wiley   +1 more source

不同生境的多枝柽柳种群空间分布点格局分析

open access: yes, 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
core  

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]

open access: yes, 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
core   +2 more sources

Mapping Measurement to Theory in Policy Evolution: A Case of Net Metering Policies of the United States

open access: yesPolicy Studies Journal, EarlyView.
ABSTRACT The examination of policy evolution has important practical implications, but current literature often only evaluates changing policy goals and instruments at the macro‐level, overlooking changes that occur at the more granular, micro‐level of policy text.
Graham Ambrose   +1 more
wiley   +1 more source

攀枝花苏铁种群生态地理分布、分布格局及采挖历史的研究

open access: yes, 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
core  

张力和流场分布对张力腿涡激振动响应的影响分析

open access: yes, 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
core   +2 more sources

open access: yes野生动物学报, 1994
貉貉(NyctereutesProcxonoidesGray)属于食肉目犬科。主要分布于亚洲东南部。在原苏联分布在黑龙江流域、乌苏里江流域向北分布到萨哈林半岛。在中国分布在东北、华北、华中、华南和西南地区一直延伸到越南北部。在日本和朝鲜半岛也有分布。...
高犁为
doaj  

Addressing the Right to Food Through Food Expenditure Burdens: Distributional Evidence Among Low‐Income Farming Families in Brazil (2012–2023)

open access: yesWorld Food Policy, Volume 12, Issue 2, November 2026.
ABSTRACT Household food expenditure continues to be a key factor in ensuring the realization of the Human Right to Adequate Food. Particularly in Brazil, access to food can be limited by economic constraints in vulnerable families, especially among farming families, who have been more vulnerable to food insecurity in recent years in the country.
Lucas de Almeida Moura   +3 more
wiley   +1 more source

Local Public Goods Provision in the Post-Agricultural Tax Era in Rural China [PDF]

open access: yes
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
core  

阿克苏拜城天山区盘羊和北山羊的分布与种群资源现状

open access: yes野生动物学报, 2010
根据2008~2009年实地考察研究结果,着重就该区2种有蹄类动物的分布、种群数量以及有关问题作概要性探讨。调查研究结果表明:(1)老虎台盘羊分布区盘羊平均密度=8.49/8=1.06只/km2,黑英山盘羊分布区盘羊平均密度=5.34/3=1.78只/km2。整个分布区盘羊种群数量1 488只,其中,老虎台分布区种群数量=480×1.06=509只,黑英山分布区种群数量=550×1.78=979只。(2)老虎台北山羊分布区北山羊平均密度=14.59/5=2.92只/km2 ...
阿布力米提·阿布都卡迪尔   +5 more
doaj  

Home - About - Disclaimer - Privacy