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In public policy processes, collective learning among policy actors is important in shaping how these processes unfold and the types of policy outcomes that may result. Despite a widespread interest in learning by policy scholars, researchers face a number of conceptual and theoretical challenges in studying learning across different collective settings within policy processes. In this article, we offer a theoretically grounded approach to defining and understanding collective‐level learning. In defining learning, we first draw out the connection between learning processes and learning products, both cognitive and behavioral. In examining learning processes, we further explore the relationship between individual and collective learning. Then we identify and define the key characteristics of collective settings that will likely influence learning processes. We conclude by offering recommendations for policy scholars to apply this approach in studies of learning across diverse policy contexts.  相似文献   
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During prehistory fire-setting was the most appropriate technique for exploiting ore deposits. Charcoal fragments found in the course of archaeological excavations in a small mine called Mauk E in the area of Schwaz/Brixlegg (Tyrol, Austria) are argued to be evidence for the use of this technology. Dendrochronological analyses of the charcoal samples yielded calendar dates for the mining activities showing that the exploitation of the Mauk E mine lasted approximately one decade in the late 8th century BC. Dendrological studies show that the miners utilised stem wood of spruce and fir from forests with high stand density for fire-setting and that the exploitation of the Mauk E mine had only a limited impact on the local forests.  相似文献   
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Cave bear (Ursus spelaeus) behavioural ecology, as evidenced through population dynamics, is crucial for improving our understanding of why this species went extinct. Despite the fact that the bones of this species have been recovered in very large quantities, allowing for extensive study, fundamental questions regarding its life-ways remain unanswered. We present research using geometric morphometrics (GMM) on molars to investigate population structure based on morphological variation over space and through time. This preliminary work deliberately restricts the geographic catchment area for sampling, allowing for a meaningful appraisal of scale of variation within a spatially conservative framework. Our results demonstrate no significant morphological variation evident temporally and a small but statistically significant degree of shape variation geographically despite the proximity of the study localities. These findings suggest that an accurate quantitative exploration of morphospace may be an important source of evidence on environmental and climatic shifts and the resulting influence on animal morphology.  相似文献   
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This article studies the performance of economic base isolators using tyres filled with elastomeric recycled materials. The research was conducted to analyze base isolators to be used in developing nations, where the application of conventional elastomeric rubber bearings due to economic reasons is limited.

The tested isolators are made of kart tyres filled with different recycled elastomeric materials and aggregates. Dynamic and static tests proved acceptable vertical to horizontal stiffness ratio of the bearings and shake table tests showed an excellent enhancement of the base isolated structural response compared to the corresponding fixed base structure.  相似文献   
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The Cambodian conflict and the increase of the Cold War tension following the Soviet invasion of Afghanistan posed major challenges to Japan’s Southeast Asia policy but, contrary to what is claimed in the existing research, did not halt Tokyo’s efforts to promote peaceful coexistence between the countries of ASEAN and Indochina. Declassified documents and other primary sources show that through the adoption of a twin-track diplomatic line, Japan acted as an “Asian member of the West”, committing to the anti-Soviet alignment but at the same time continuing to pursue its regional objectives. By engaging Vietnam and striving for a “regional” solution to the Cambodian conflict, Japan followed an independent diplomatic line, eventually expanding its role in Southeast Asia beyond the economic dimension to security issues. In the end, Japan’s bridging efforts in Southeast Asia, envisioned by Prime Minister Fukuda in 1977, helped Tokyo to lay the foundation for its involvement in the mature stage of the Cambodian peace process after the late 1980s.  相似文献   
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