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141.
Emilia Palonen 《GeoJournal》2008,73(3):219-230
As in most parts of Central and Eastern Europe, there is a tradition in Hungary of changing street names and memorials in
the wake of major political transitions. This article focuses on the change of street names and memorials, i.e. the city-text,
in Hungary’s political capital, Budapest, between 1985 and 2001. The city-text in Budapest became a locus of dispute between
different political authorities, including the nation state, the metropolitan municipality, and the district, each bearing
different political ideals during and after the fall of communism. Discursive changes in the post-communist city-text emerged
expressing specific conceptions of national sovereignty, but the direction of the changes were debated. Different levels of
administration in Budapest and Hungary had divergent visions of what the new discourse on national sovereignty should be.
The changes, therefore, did not express a simple transition to an agreed-upon post-communist value system, but were the result
of a symbolic struggle between different levels of administration over what should be commemorated in the city-text. 相似文献
142.
Lars Olov Andersson 《Physics and Chemistry of Minerals》2008,35(9):505-520
The EPR spectra of Maxixe-type beryl contain a large number of overlapping signals. The angular dependence of the 1:3:3:1
signal typical for the CH3 radical shows that this radical is located at the center of the channel cavity with its symmetry axis parallel to the crystal
c-axis and is rotating around this axis. Its EPR spectrum is axially symmetric with g
// = 2.00263, g
⊥ = 2.00249 and A// = 2.288 mT, A⊥ = 2.256 mT. These anisotropies have the opposite signs of those found for surface-adsorbed methyl radicals. Hydrogen atoms
are located at position 2a at the center of the beryl cavity and the EPR parameters of the narrow doublet signal are A
0 = 1,407 MHz and g = 2.00230. Another doublet signal, which is broader and has axial symmetry with g
// = 2.00265, g
⊥ = 2.00625 and A// = 0.895 mT, A⊥ = 0.885 mT, could come from a HCO3 radical. One narrow and easily saturated signal with g
// = 2.00227 and g
⊥ = 2.00386 is interpreted to arise from a carbon monoxide radical in the beryl channel, oriented with its axis parallel to
the crystal c-axis. Additional weak doublet lines, which have similar g values as the carbon monoxide radical, are created by nearby hydrogens. A powder spectrum with g
// = 2.0017 and g
⊥ = 2.0004 appears upon UV irradiation of the single crystal and is easily saturated. This spectrum is interpreted to arise
from a carbon dioxide radical, which rotates around its symmetry axis. 相似文献
143.
An increasingly utilized strategy for expanding conservation in the developing world has been the promotion of protected areas
that supersede national borders. Alternatively known as transfrontier biosphere reserves, transfrontier or transboundary conservation
areas, or Peace Parks, these protected areas are aggressively advanced by conservation agencies for their purported ecological
and economic benefits. This article provides a comparative assessment of two case studies to understand the various impacts
of transboundary conservation. The Great Limpopo Transfrontier Park, which unites protected areas in South Africa, Mozambique
and Zimbabwe, is contrasted with efforts to protect jaguars along the United States–Mexico border. We argue that while these
cases are promising for the purposes of biodiversity protection, they demonstrate that transboundary conservation can minimize
political context, contributes to the hegemony of international conservation agendas, and remains closely linked to economic
neoliberalism and decentralization in the developing world.
相似文献
Brian KingEmail: |
144.
Until recently the traditional spatial configuration of the European geography was based upon the core-periphery model. The
‘pentagon’, broadly defined as lying between London, Paris, Milan, Munich and Hamburg, was seen as the core area characterised
by having the highest concentration of economic development in the European Union (EU), with the remainder of the European
territory viewed as peripheral, albeit to varying degrees. In a number of cases such peripheral areas equated with clear regional
disparities. The elaboration of the European Spatial Development Perspective (ESDP) (CEC, European spatial development perspective, towards balanced and sustainable development in the territory of the
European Union, 1999) challenged this core-periphery model. European spatial planning policies, aimed at encouraging social
and economic, and with ever increasing importance, territorial cohesion, seek amongst other aspects to encourage the development
of a balanced and polycentric urban system. This paper adopts a network analysis approach to the analysis of air passenger
flows between some 28 principal European metropolitan urban regions. The evaluation of these flows contributes to an enhanced
comprehension of the spatial dynamics of the European metropolitan territory which goes beyond that deriving from the more
standard analyses of the individual components of the urban system. Several indicators are used, deriving from gravitational
modelling techniques, to analyse the complexity of the air passenger flows. A multidimensional scaling (MDS) technique is
introduced in order to interpret and visualise the resulting spatial configuration and positioning of the different metropolitan
centres within the conceptual European ‘space of air passenger flows’, thereby contrasting with the more traditional map-based
geographical image of Europe, based upon Cartesian coordinates.
相似文献
Malcolm C. BurnsEmail: |
145.
This paper explores the links between a strategic policy, urban consolidation, and house prices by examining the changes in
the mix of housing and in house price for the period 1991–2004. We contend that urban consolidation could be seen as a source
of additional supply, (which might be expected to be felt in lower prices and so contribute to a local policy objective) but
also as a stimulus to demand (by developers who could bid up the price of lots where it was understood more housing could
be built). Analyses were carried out at the metropolitan and sub-regional scales using correlation tests. The research finds
very weak statistical connections, and concludes that this policy has not been associated with price changes. 相似文献
146.
Corey Johnson 《GeoJournal》2008,72(1-2):75-89
As John Agnew (Political geography: a reader, 1997) has argued, political and economic change often occasions competing visions of the scales that are appropriate for organizing particular political and economic activities. Nowhere is this more evident than in the European Union, and eastern Germany offers compelling evidence of the contested nature of contemporary scalar politics. Yet a recent debate in human geography (see, e.g. Marston et al., Transactions of the Institute of British Geographers 30:416–432, 2005) calls into question the very concept of scale and rejects its hierarchical conceptualization. In light of this debate, it is appropriate to draw on real-world case studies to examine the ways in which geography figures into policy. Drawing on field work in Saxony, evidence is offered in the form of competing visions of regionalism in the EU context. The evidence presented complicates both hierarchical and flat notions of scale. The current process of querying space to identify those scales that are best-suited for the globalized economy offers insights into both the socially constructed nature of scale as well as the ways in which scalar lenses help to illuminate the geographical aspects (and consequences) of strategies for coping with structural changes. 相似文献
147.
148.
Concern for natural hazard-triggered technological disasters (Natech disasters) in densely populated and industrialized areas
is growing. Residents living in urban areas subject to high natural hazard risk are often unaware of the potential for secondary
disasters such as hazardous materials releases from neighboring industrial facilities, chemical storage warehouses or other
establishments housing hazardous materials. Lessons from previous disasters, such as the Natech disaster during the Kocaeli
earthquake in Turkey in 1999 call for the need to manage low frequency/high consequence events, particularly in today’s densely
populated areas. However, there is little guidance available on how local governments and communities can assess Natech risk.
To add to the problem, local governments often do not have the human or economic resources or expertise to carry out detailed
risk assessments. In this article, we propose a methodology for preliminary assessment of Natech risk in urban areas. The
proposed methodology is intended for use by local government officials in consultation with the public. The methodology considers
possible interactions between the various systems in the urban environment: the physical infrastructure (e.g., industrial
plants, lifeline systems, critical facilities), the community (e.g., population exposed), the natural environment (e.g., delicate
ecosystems, river basins), and the risk and emergency management systems (e.g., structural and nonstructural measures). Factors
related to vulnerability and hazard are analyzed and qualitative measures are recommended. Data from hazardous materials releases
during the Kocaeli, Turkey earthquake of August 17, 1999 are used as a case study to demonstrate the applicability of the
methodology. Limitations of the proposed methodology are discussed as well as future research needs.
相似文献
Norio OkadaEmail: |
149.
The Cambrian-Vendian groundwater body plays an important role in drinking water supply of capital Tallinn and other settlements
in northern Estonia. Water quality in this deep-seated confined groundwater body is influenced by the intrusion of present-day
seawater and pumping-induced upward migration of deeper saline groundwater. The aim of this study is to evaluate the threshold
values applying the methodology worked out within the EU 6th FP project “Background criteria for the identification of groundwater
thresholds (BRIDGE)” and to compare the results with the values proposed by local authorities. A database containing 250 monitoring
points was completed and used for the calculation of natural background levels (as the 90 and 97.7 percentile) in groundwater.
The calculation of threshold values is based on natural background levels and reference values. In case of Cambrian-Vendian
groundwater body the receptor is drinking water, thus limit values set by Estonian drinking water standard were used as reference
values. The threshold values proposed by local authorities are more or less the same as calculated by BRIDGE methodology.
Exceptionally different values are derived in case of chloride and ammonium. 相似文献
150.
Two algorithms for in-situ detection and identification of vertical free convective and double-diffusive flows in groundwater
monitoring wells or boreholes are proposed. With one algorithm the causes (driving forces) and with the other one the effects
(convection or double-diffusion) of vertical transport processes can be detected based on geophysical borehole measurements
in the water column. Five density-driven flow processes are identified: thermal, solutal, and thermosolutal convection leading
to an equalization, as well as saltfingers and diffusive layering leading to an intensification of a vertical density gradient.
The occurrence of density-driven transport processes could be proven in many groundwater monitoring wells and boreholes; especially
shallow sections of boreholes or groundwater monitoring wells are affected dramatically by such vertical flows. Deep sections
are also impaired as the critical threshold for the onset of a density-driven flow is considerably low. In monitoring wells
or boreholes, several sections with different types of density-driven vertical flows may exist at the same time. Results from
experimental investigations in a medium-scale testing facility with high aspect ratio (height/radius = 19) and from numerical
modeling of a water column agree well with paramters of in-situ detected convection cells. 相似文献