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1.
农业生产空间是农村基本功能的载体。从资本“三重循环”视角出发,将“空间的生产”理论引入农业研究,提出并构建农业空间生产资本化的作用逻辑及其特征表征,并以山东省泰安市村庄为研究单元,研究其农业空间生产资本化特征、模式表征及空间规律。发现,泰安市农业生产具有资本投入集约化、空间生产集中化、组织分工专业化等特征;农业空间生产资本化模式共有四种,在空间上呈现出以中心城区为圆心,圈层式向外拓展的规律性,农业空间生产资本化度和三重特征都表现出由内向外先增后缓降的格局。在乡村振兴背景下,识别村庄农业发展模式,根据要素条件,分类指导农业种植结构调整,有利于促进农村多功能有机融合,实现乡村农业产业兴旺发展目标。  相似文献   
2.
Critical physical geography (CPG) calls for integrative research on material landscapes and the socio-political dynamics of scientific knowledge production. Network analysis, a rich tradition of tools and approaches for analyzing relational information, has seen little use in the CPG literature to date. This represents a fruitful opportunity, as many of CPG's core interests—knowledge politics, histories of scientific concepts, and ecosocial relations—can be effectively analyzed using network techniques. In this article, I argue for adapting network approaches to CPG. First, I provide an overview of various network concepts, approaches, and their origins. I then discuss bibliometric network techniques for “science mapping” including co-word, co-authorship, and citation analyses. Next, I describe discourse network analysis, a recent mixed-method approach from political science. Finally, I discuss overlaps with emerging approaches from qualitative and visual network analysis. In each section, I provide existing and hypothetical examples, as well as software and visualization techniques, that demonstrate how network approaches could add new insights to CPG and related scholarship. Linking CPG with the diverse traditions of network analysis has the potential to produce new empirical understandings and bring the field into conversation with a growing body of research that spans the social sciences, natural sciences, and humanities.  相似文献   
3.
Inventing is an important prerequisite for industrial economies to remain technologically competitive. Yet it is not well known how inventive companies of domestic or foreign ownership can affect a nation's technological base and, ultimately, its spatial-economic system. The present study examines this relationship in Canada by investigating the performance of its indigenous and foreign-owned inventive companies at the national, subnational, and urban levels. The results indicate that: (1) Canada's indigenous inventive companies are distinct from their foreign-owned counterparts in that they are generally smaller, are more apt to have teams of inventors, are more likely to develop product inventions, have come to manage a greater share of this nation's inventions, and are increasing their role in key Canadian industries; and (2) geographically, Canada's two largest cities and its core region were adversely affected by the declining inventiveness of American-controlled companies during the 1980s. L'esprit ?invention est une nécessité pour que les économies industrielles restent en conditions de concurrence technologique. Cependant, on connaît très peu de la manière que les entreprises inventives de propriété domestique ou étrangère affectent la base technologique ?un pays et, enfin, affectent son système spatio-écono-mique. La présente étude considère ces rapports au Canada au niveau national, sous-national et local, en exminant les performances des entreprises inventives indigènes et étrangères. Les résultats indiquent (1) qu'au Canada les entreprises indigènes et inventives diffèrent de leurs analogues étrangers: en général elles sont plus petites, ont plus tendance à consister en équipes ?inven-teurs, sont plus susceptibles de développer les inventions produites, produisent une plus grande part des inventions canadiennes, et sont en train ?augmenter leur rôle dans les industries canadiennes; et (2) que le déclin de ?esprit ?invention dans les entreprises dirigées par les américains a affecté défavorablement les deux villes les plus grandes au Canada, ainsi que la partie centrale du pays, pendant les années 1980. Mots-clés: invention, Canada, propriétéétrangère, technologie, produit  相似文献   
4.
This paper summarizes recent archaeological research efforts, and changing perspectives, about the native history of the Caddo peoples who lived in the Caddoan Archaeological Area, which centers on the Great Bend of the Red River in Oklahoma, Texas, Arkansas, and Louisiana. Of particular focus are the origins and early developments of the Caddoan tradition, regional diversity, subsistence changes and agricultural intensification, sociopolitical dynamics, and Caddoan-European interaction.  相似文献   
5.
ABSTRACT

The territories of the former kingdom of Judah were only sparsely settled during the Persian period, as exemplified by the extreme rarity of domestic structures unearthed in excavations. Viewed against this background, the large number of excavated forts and isolated administrative buildings from this period is remarkable, and they apparently outnumber the period's excavated dwellings. Not only is this an extremely unlikely situation, but various lines of evidence, pertaining to specific sites as well as to the phenomenon as a whole, render the possibility that all these structures were forts or administrative buildings re-examines implausible. Consequently, this article reexamines the phenomenon within the social landscape of the region in particular, and of the Achaemenid empire in general, in an attempt to embed those unique buildings within the broader demographic and political reality of this time. Given the location of many of the sites and the finds unearthed in them, and in light of the demographic reality in the region and of the broader Achaemenid imperial policy, the article suggests that most of the so-called forts were estates, created in the process of the resettlement of this previously devastated region.  相似文献   
6.
Since the mid-1990s German technology policy has experienced a paradigmatic shift from standard grant schemes towards a region-oriented and competition-based R&D policy. Currently, a new policy experiment, the InterClust contest, is under way, trying to simultaneously foster place-based innovation, R&D internationalization and the internationalization of innovative places. The current paper analyses the new policy, relating it to the recent literatures on heterogeneous firms and on cluster-life cycles, and presents results from a firm survey performed in 21 winner regions of InterClust. Findings show that the new funding scheme takes insights from recent theoretical developments into account and addresses important impediments to firm and cluster internationalization. Although it is too early for an overall assessment, it is argued that the long-term impact will critically depend on the inflow of heterogeneous knowledge and the strength of intra-regional mobilization effects.  相似文献   
7.
William Scott Owen figured prominently in Montgomeryshire history by being deeply involved with the lives of working people and active in local politics. He was an incomer from the south of England and a stalwart of the Anglican faith and the Tory party. He spent the whole of his working life in Montgomeryshire and came to be deeply respected in a part of Britain noted for its Nonconformity and Liberalism. Scott Owen was agent on the Gregynog Estate, which lies in the south east of the county, much of it now belonging to the University of Wales. This study of his life provides a vivid picture of the county in the late Victorian and Edwardian period and discusses why he became so well regarded.  相似文献   
8.
9.
广西桂平博物馆藏东汉铜甑对于研究广西地区青铜器冶铸技术的发展具有重要的研究价值。但器物长期保存于潮湿环境中,矿化严重、保存状况较差,亟须保护修复。本研究应用X射线影像观察、金相显微镜、扫描电镜及能谱分析、模拟实验验证等方法研究了器物的铸造工艺、合金成分以及锈蚀产物成分。结果表明该器物为整体铸造成形,器物铸造时使用了轮制技术、刮板造型工艺以及铸后刻纹的工艺,箅部范块制作过程是用器身模翻制器身范后脱模,将器身模的圈足部分切下,然后在圈足泥模上刻出箅部型腔。在此基础上,遵循最低限度干预原则,力求将传统的文物修复手段与现代修复理念相结合,通过除锈、修补等保护修复措施后,不但提高了器物的整体稳定性,而且达到了可以展陈,发掘文物潜在价值的要求。  相似文献   
10.
Epistemic communities are an established concept in the study of international relations but can also explain policy change at the domestic level. This article asks why some epistemic communities manage to convince decision makers of their preferred policies while others do not. It suggests that the reason lies in the causal mechanism of epistemic communities' influence on decision makers, mediated by decision makers' demand for expert input. Most epistemic communities scholarship focuses on single case studies where the communities' influence on policy was strong and clear, leading to an overestimation of the groups' influence. To help correct this probable bias, this article compares a successful case of epistemic community influence (health technology assessment in Poland) with an unsuccessful example of the same policy (in the Czech Republic). The juxtaposition allows for unpacking of the necessary parts of the causal mechanism (emergence of an epistemic community, its activity, access to decision makers, and successful suasion) and separating them from the crucial scope condition. Decision makers' uncertainty about the policy issue at hand has traditionally been the key scope condition for epistemic communities but the successful Polish case demonstrates that epistemic communities can be influential even in highly certain areas of routine policymaking, leading to a reconceptualization of uncertainty as policymakers' demand for expert input. Demand can originate from various sources, but any change of it affects individual parts of the causal mechanism, leading to a success or failure of epistemic communities' policy enterprise.  相似文献   
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