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121.
The goal of this discussion paper is to examine the relevance of selected influential theoretical and conceptual approaches to regional competitiveness for specific geographical and institutional contexts of Central European (CE) regions. We argue that strategic documents and policies (both nation- and region-wide) in CE countries are based on un-critical applications of a few popular concepts of competitiveness that were originally proposed and mainly applied in Western European and US regions. Existing empirical evidence documents a strong role of exogenous factors of competitiveness in CE regions, the in-house character of firm innovations and weak demand for innovations, and other impediments of R&D collaboration. We suggest that these (and other factors) limit the applicability of concepts such as regional innovation systems and Porterian clusters in the context of many CE regions. On the other hand, we argue that some other concepts such as the global production networks perspective or related variety and economic complexity can provide some relevant and inspiring frameworks for analysing regional competitiveness in CE countries.  相似文献   
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This article presents a method to identify “Absolute and Relative Employment Concentration (AREC) areas” for a particular industry. Two novel characteristics of the method are that it simultaneously analyses AREC, and that it combines spatial concentration per area with the spatial concentration in neighbouring areas. The method is easy to understand and apply. It is developed to assist regional policy makers and corporate decision-makers with their investment decisions related to new infrastructure or plants. The identification of concentration areas also allows for analysing the performance of these areas in relation to characteristics such as infrastructure availability and the housing and labour market. This can yield new academic insights that are relevant for regional planners. An application of the newly developed method to five industries in a Dutch province subdivided into 502 areas illustrates the value of the method in comparison to other methods.  相似文献   
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As the sobriquet «Zweistein» suggests, within the theoretical physics community Wolfgang Pauli came to be regarded as second in eminence only to Albert Einstein. Over a period of thirty-five years, they interacted both intellectually and personally. This paper focuses on four interrelated topics of their discussions. 1) The theory of relativity: at the age of twenty, Pauli prepared the definitive survey of relativity, a survey which he revised near the end of his life and which remains invaluable to physicists and historians of physics. 2) Unified field theories: although initially sympathetic to Einstein's search for a unified theory of electromagnetism and gravitation, and having made important contributions to the subject, Pauli came to regard such efforts as fruitless. 3) Foundations of quantum mechanics: Pauli's negative evaluation of Einstein's program grew out of their sharply differing evaluations of the role that quantum mechanics would play in the future, development of theoretical physics. 4) Quantum gravity: Pauli recognized that, until the achievement of a successful reconciliation of quantum mechanics and general relativity — an achievement that still eludes us — Einstein's challenge to quantum mechanics could not be laid to rest.  相似文献   
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ABSTRACT This paper develops a model of social networks different from those presented in the recent literature. In contrast to existing models, the level of investment in link formation is a continuous decision variable, and links form stochastically rather than deterministically, with the probability depending on the noncooperative investment choices of both parties. Since the network structure is then stochastic rather than deterministic, the actual pattern of links cannot be specified, as in previous models, with the analysis focusing instead on which links are most likely to form. This alternate approach leads to a much simpler mathematical structure than in previous work. The analysis, which is couched in the context of friendship networks, shows that individual investment in friendship formation is too low. In addition, the analysis shows that, in an asymmetric setting where one individual has personal magnetism or a broad group of acquaintances, friendship links involving this attractive agent are most likely to form.  相似文献   
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Pricing, Capacity Choice, and Financing in Transportation Networks   总被引:5,自引:0,他引:5  
Abstract.  This paper explores interrelations between pricing, capacity choice, and financing in transportation networks. We build on the Mohring‐Harwitz result on self‐financing of optimally designed and priced roads and investigate it in a network environment under various types of second‐best regulation. A small network model with endogenous car ownership demonstrates that optimal congestion pricing and capacity choice over an entire network may cause user prices to increase more in initially mildly congested areas compared to heavily congested areas. Furthermore, a flat kilometer charge under optimal capacity choice may result in first‐best efficiency gains.  相似文献   
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In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies, new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques that inform many areas of archaeological inquiry.  相似文献   
130.
This article focuses on the presence of humans in Siberia and the Russian Far East at the coldest time of the Late Pleistocene, called the Last Glacial Maximum (LGM) and dated to c. 20,000–18,000 rcbp. Reconstruction of the LGM environment of Siberia, based on the latest models and compilations, provides a background for human existence in this region. Most of Siberia and the Russian Far East at c. 20,000–18,000 rcbp was covered by tundra and cool steppe, with some forest formations in the river valleys. Climate was much colder and drier than it is today. Eighteen Upper Paleolithic sites in Siberia are radiocarbon dated strictly to the LGM, and at least six of them, located in southern parts of western and eastern Siberia and the Russian Far East, have solid evidence of occupation during that time span. It seems clear that southern Siberia was populated by humans even at the height of the LGM, and that there was no dramatic decline or complete disappearance of humans in Siberia at that time. The degree of human adaptation to periglacial landscapes in the mid-Upper Paleolithic of northern Eurasia was quite high; humans coped with the cold and dry environmental conditions using microblade technology, artificial shelters, tailored clothes, and megafaunal bones as fuel. An erratum to this article can be found at  相似文献   
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