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Distance‐based methods are applied in various fields of research. In this paper, a new relative distance‐based method, the W function, is introduced. This method contributes to the assessment of spatial patterns of economic activities using the stochastic Monte Carlo simulation, and supplements the typology of distance‐based methods recently drawn up by Marcon and Puech. The capability of the W function is compared with results from the Kd and the recently defined m function methods, which are widely used for monitoring the spatial distribution of economic activities by considering several theoretical and empirical examples. The W function appears to provide more precise estimations of the density of economic activities compared to the m and Kd functions, particularly in cases of complex patterns such as double clustered distribution. It also appears to provide a more accurate evaluation of dispersion.  相似文献   
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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   
4.
The aim of this paper is to present and discuss empirical evidence on the dynamics of occupation and site formation processes from contemporary mobile campsites in Northwest Siberia. The questions posed are derived generally from archaeological studies of Upper Paleolithic record in Europe. We document the active Nenets summer camps at lakes and the abandoned winter and spring camps in the open tundra and the forest tundra. Analysis of the floral and zoological resources shows that plant resources and fish are available predominantly in the summer while reindeer are abundant in these regions in fall and winter when they return from summer pastures further north. When natural resources are not available, groups supplement with food purchased at shops. Within these living camps, “structures évidentes” and “structures latentes” of classical French paleoethnology cannot be distinguished as clearly as at Upper Paleolithic sites: and architectural remains, ash from hearths, and other objects may be removed from the central areas towards the site peripheries. However the investigated camps preserve a discrete structure with interior living areas (including children’s playgrounds), exterior areas with evidence of reindeer carcass processing, woodworking, and other activities, peripheral toss zones, and dispersed activity remains in the surrounding landscape.  相似文献   
5.
The frequency content of ground motions seems to be one of the most important parameters to explain the structural damage experienced during worldwide strong earthquakes. The frequency content of ground motions can be characterized by various stochastic and/or deterministic indicators: the frequency bandwidth indicator ? (Cartwright & Longuet-Higgins) related to the power spectral density function and, respectively, the control (corner) period Tc of the structural response spectra or the mean period TM . Peak ground velocity (PGV) and the ratio PGA/PGV can be used as either damage potential parameters or frequency content indicators. A comparative analysis of stochastic and deterministic frequency content indicators and of PGV is applied to a set of 30 strong ground motion records having peak ground acceleration (PGA) from 0.2–0.8 g and recorded on 4 continents during the last 70 years.  相似文献   
6.
It has become commonplace to talk about humans hunting mammoths, and overhunting is thought to have been one of the causes of the mammoth extinction. However, definite evidence of mammoth kills by humans remains surprisingly scarce. Here we show convincing evidence of mammoth hunting in the Siberian Arctic between 29 000 and 27 000 14C years BP. Our data set, from the Yana Upper Palaeolithic site (Siberian Arctic), includes the following: fragments of lithic points and ivory shaft embedded in two mammoth scapulae; two identical holes made by projectiles in a mammoth scapula and a pelvic bone; mammoth tongue bones found in the cultural layer far away from the main mammoth bone accumulation, indicating the consumption of fresh mammoth meat; and a narrow mammoth bone size distribution, implying hunting selection based on animal size. The data suggest that Palaeolithic Yana humans hunted mammoths sporadically, presumably when ivory was needed for making tools. Such non-intensive hunting practiced by humans over millennia would not be fatal to a sustainable mammoth population.  相似文献   
7.
Abstract

This article addresses the problem of the homogeneity and structure of the identity of the European Far North of Russia. The author comes to the conclusion that the structure of this territory has been determined since the sixteenth century by a rift between the Kola North and the Arkhangelsk North. While this rift deteriorated or was partially healed at different times, the differentiation of the European Far North of Russia into two territorial segments persisted over the periods of Muscovy, the Russian Empire and then the Soviet Union. Although the Kola Peninsula was integrated for two centuries (1708–1921) into the vast province with a centre in the city of Arkhangelsk, it not only preserved features of its identity, but in fact managed to strengthen them, which eventually led to the administrative separation of the Kola North from the Arkhangelsk Province. The development of the two northern territories has been accompanied by competition, which is still there to a large extent. The phenomenon of the division of the Russian Far North in two parts is treated as a consequence of the importance which meridional strategic ties between the centre and the outlying northern areas acquired in the Russian State, in contrast to the weaker latitudinal peripheral ties between the provinces.  相似文献   
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This paper follows the struggles of Russian coal miners who first challenged the Soviet regime in 1989 and helped precipitate its downfall in 1991. In the Arctic city of Vorkuta, the movement's most militant and radical center, the dreams of workers have again, as in 1917, become bonds of their affliction. In response to invading market forces, the city strike committee has turned from support of the new regime to renewed opposition, the independent trade union movement increasingly throws its weight behind the once reviled mine management, and the mines themselves have rallied around the conglomerate, long a symbol of arbitrary power.  相似文献   
9.
Additionality is one of the key principles driving the functioning of the EU cohesion policies (ECP). The present paper studies how additionality affects the impact of firm-level investment support on firm investment behaviour in differently competitive markets. We find that the investment additionality and the level of competition importantly affect the firm investment behaviour. Imposing additionality on the ECP investments in perfectly competitive markets causes distortions in the capital market and leads to lower welfare levels. In contrast, without the enforcement of additionality, the distortions are zero and the investment support fully benefits the firms. In an imperfectly competitive environment, the firm-level investment support may increase investment and may be welfare increasing with and without the enforcement of the investment additionality.  相似文献   
10.
The August 30, 1986 (MW ?=?7.1) and May 30, 1990 (MW ?=?6.9) Vrancea intermediate-depth earthquakes, despite their almost similar magnitudes, have produced very different spectral contents as shown by the strong ground motions recorded in Bucharest and its surroundings. The differences can be attributed to different epicentral distances and to different values of the stress drop. The characteristics of the seismic ground motions recorded in Bucharest area in the 1986 and 1990 seismic events are discussed in the context of (a) the source characteristics of the two earthquakes and (b) the local soil conditions in Bucharest. Furthermore, an attempt is made to determine the soil factors S defined in EN 1998-1 EN 1998-1. 2004. Design of Structures for Earthquake Resistance – Part 1: General Rules, Seismic Actions and Rules for Buildings, CEN.  [Google Scholar] for the Bucharest area, based on the strong ground motion dataset recorded during the two seismic events.  相似文献   
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