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81.
The spatial dimension is a key paradigm in price determination, as attested by recent studies in the literature that highlighted the differential in market behavior between spatial and non‐spatial pricing settings. In this paper, we develop a model of spatial pricing for multi‐market heterogeneously distributed resources, with an application to the Swedish forestry sector. The focus of the model is to estimate the impact of spatial interaction on the demand for resources in terms of resource allocation, competition, and pricing. In its core, the pricing mechanism relies on a supply–demand framework. Using disaggregated data at the gridcell level for forest feedstock supply and harvesting costs in Sweden, we construct regional supply curves for each gridcell assuming a maximum transportation distance to delimit the potential market. Demand nodes are exogenously determined and are adjusted using a distance‐decay model to assess demand pressure across locations. We apply the model empirically to assess the impact on forest feedstock prices of a 20 TWh increase in biofuel production. 相似文献
82.
83.
This review discusses recent challenges to the welfare state arising from the Great Recession (GR). The GR was a significant event for social policy analysts, as it tested the responsiveness of welfare systems in the midst of a recent trend toward austerity politics in advanced economies. Social policy changes were part of the toolkit advanced democracies used to respond to the GR, and the welfare state mitigated the consequences of the GR. However, a stark limitation of the social safety net in the United States was the failure to assist immigrant households. The nexus of immigration and social policy is likely to be a significant controversy as we consider the meaning of social citizenship. 相似文献
84.
Stephen G. Perz Marcellus M. Caldas Eugenio Arima Robert J. Walker 《Development and change》2007,38(3):529-551
Roads have manifold social and environmental impacts, including regional development, social conflicts and habitat fragmentation. ‘Road ecology’ has emerged as an approach to evaluate the various ecological and hydrological impacts of roads. This article aims to complement road ecology by examining the socio‐spatial processes of road building itself. Focusing on the Brazilian Amazon, a heavily‐studied context due to forest fragmentation by roads, the authors consider non‐state social actors who build ‘unofficial roads’ for the purpose of gaining access to natural resources to support livelihoods and community development. They examine four case studies of roads with distinct histories in order to explain the socio‐spatial processes behind road building in terms of profit maximization, land tenure claims, co‐operative and conflictive political ecologies, and constraints as well as opportunities afforded by the biophysical environment. The study cases illustrate the need for a multi‐pronged theoretical approach to understanding road building, and call for more attention to the role of non‐state actors in road construction. 相似文献
85.
86.
Markus Leibenath Anke Hahn Robert Knippschild 《Standort - Zeitschrift für angewandte Geographie》2007,15(1):36-40
Der deutsch-tschechische Grenzraum liegt gewisserma?en in einer Sandwich-Position zwischen verschiedenen europ?ischen Makroregionen;
auf europ?ischer Ebene wird er bislang eher als Verbindungselement wahrgenommen. Seine innere Struktur ist von einer relativ
geringen Besiedlungsdichte und ausgepr?gten Stadt-Land-Unterschieden gekennzeichnet. Im Frühjahr 2006 gründeten die beiden
nationalen Regierungen eine deutsch-tschechische Arbeitsgruppe für Raumentwicklung. Der Artikel skizziert, welche Ziele und
Erwartungen damit verbunden werden und welche Funktionen ein solches Gremium übernehmen kann. Dazu wird zun?chst die Ausgangssituation
dieses Raumes skizziert. Abschlie?end wird das m?gliche Leitbild des „Mitteleurop?ischen Kristalls“ vorgestellt. 相似文献
87.
Historians disagree over the meaning of the declaration on 17June 1789 by Third Estate deputies, along with a few clergy,that they constituted a National Assembly, onethat could act in place of the Estates General and despite theabsence of most Noble and Clerical deputies. This article reconstructsthe debates of 1516 June 1789 leading up to this declaration,finding in deputy memoirs, letters and newspaper accounts fifty-eightspeeches given by thirty-eight deputies supporting several alternativeproposals. Careful analysis of the speeches demonstrates thatselection of the title National Assembly was a result of contingentevents and political compromise, primarily chosen as a meansto end the stalemate between the Orders over verification ofdeputy credentials and over whether voting in the Estates Generalwould be by head or by Order. It thus calls into question argumentsthat the declaration was the necessary outcome of a pre-revolutionaryprocess. 相似文献
88.
Human and domesticate animal bone collagen δ15N values in prehistory differ generally by 3‰ or more from Neolithic to post- Roman times in Northwest Europe, leading to an assumed dietary animal protein fraction of 60–80% using a standard interpretation of δ15N values. We examine the assumptions on which this model rests and the limitations of our knowledge in the analysis of δ15N values in archaeology. We have developed a set of models which, with small changes made in assumptions (on the order of 1‰), can produce substantially lower estimates of the dietary animal protein fraction for given δ15N values. We consider the implications of various dietary animal protein fractions on agricultural carrying capacities and human population densities in prehistory. 相似文献
89.
Eregzen Gelegdorj Amartuvshin Chunag Robert B. Gordon Jang-Sik Park 《Journal of archaeological science》2007
Metallurgical study of seven cast iron artifacts recovered from sites of the former Xiongnu (BC 3rd to AD 1st), Turk (AD 6th to 8th), Khitan (AD 10th to 12th), and Mongolian empires (AD 12th to 15th) shows that the earlier Xiongnu and Turk artifacts were made of cast iron alloys of near eutectic composition. The later Khitan and Mongol objects had greatly reduced carbon content in the range of ultrahigh carbon steel rather than cast iron, and contained more than 0.5 mass % silicon as an alloying element. Inclusions high in sulfur, phosphorus or silicon are also present. These differences suggest that Mongolia experienced a technical transition a few centuries before the establishment of the Mongolian empire, which is in agreement with some written accounts. The microstructures of the cast iron artifacts are compared with the related archaeological and documentary evidence. The results suggest that the use of fossil coal in smelting and the state policy of controlling iron production were the major factors responsible for the transition. 相似文献
90.
Robert Ayson 《Australian Journal of International Affairs》2007,61(2):215-231
The proposition that Australia faces an ‘arc of instability’ to its north has been an important feature of the Australian strategic debate in the early twenty-first century. Prompted by worries in the late 1990s over Indonesia's future and East Timor's uncertain path to independence, the ‘arc’ metaphor also encapsulated growing Australian concerns about the political cohesiveness of Melanesian polities, including Papua New Guinea and Solomon Islands. While tending to overlook the divergent experiences of countries within its expanding boundaries, the ‘arc’ fed from Australia's historical requirement for a secure archipelagic screen. As such it has became an important weapon in the debate over whether the locus of Australia's strategic priorities should be increasingly global in the ‘war on terror’ period or remain closer to home in the immediate region. The ‘arc of instability’ metaphor was consequently adopted by leading Australian Labor Party politicians to argue that the Howard Coalition government was neglecting South Pacific security challenges. It became less prominent following the Howard government's greater activism in the South Pacific, signalled by Australia's leadership of the East Timor intervention in 2003. But its prominence returned in 2006 with the unrest in both Honiara and Dili. In overall terms, the ‘arc of instability’ discussion has helped direct Australian strategic and political attention to the immediate neighbourhood. But it has not provided specific policy guidance on what should be done to address the instabilities it includes. 相似文献