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Poul Ove Pedersen Civilingeniør Peter Rasmussen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):49-56
Pedersen, P. O. & Rasmussen, P., 1973: Danske provinsbyers indre differentiering og differentieringen mellem danske provinsbyer. Geografisk Tidsskrift, 72, 49–56. København, September 30., 1973. This paper analyses the inner differentiation in the three largest provincial towns in Denmark by means of a factor analysis of 25 variables characterizing the population and the housing in 40 zones, 14 in Århus (187,000 inh.), 14 in Odense (133,000 inh.), and 12 in Ålborg (123,000 inh.). The paper especially focuses on the differences in inner differentiation between the three towns. 相似文献
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Poul Ove Pedersen Viggo Hansen lektor dr. scient. Christian Wichmann Matthiessen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):71-79
Danish Journal of Geography: 71–82, 1995. This paper presents two mega events as tools in the strategic planning of the Copenhagen area. Due to growing inter-metropolitan competition, increasingly offensive and complex means are applied. This demands strong leadership, stable longterm planning and willingness to accept the costs in order to reach the objectives. Marketing versus strategic planning is discussed. The general position of Copenhagen in the European urban system gives perspective to a potential change on the South Scandinavian urban scene. New instruments of strategic planning in Greater Copenhagen are introduced. The competitive level of Copenhagen is analyzed in relation to Stockholm, Berlin and Hamburg. Two examples of mega events are discussed that represent typical elements in urban competition: cultural events and infrastructure improvements. 1) Copenhagen as ‘The cultural City of Europe’ in 1996 represents a temporary mega event. 2) The planned bridge between Copenhagen and the south Swedish city of Malmö, combined with Swedish entrance into EU, opens up for development of the first cross-national integrated large-city region outside the European centre. This is an example of a mega event which will alter the scene permanently. Both events are important issues used in developing a growth strategy for Greater Copenhagen. But neither the cultural city nor the bridge may by themselves guarantee any advantages. It depends upon the ability of local actors to develop and promote the quality of their city. The paper represents a continuation and elaboration on earlier papers, see Matthiessen (1990, 1992) and Andersen &; Jørgensen (1994). 相似文献
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Poul Brøndum 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):20-36
Biilmann, Ove: Dansk geografiundervisning. Geografisk Tidsskrift 83: 20–23. Copenhagen, June 1, 1983. Education in geography at the elementary schools in Denmark. 相似文献
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Craig A. Johnson Poul Emsbo Forrest G. Poole Robert O. Rye 《Geochimica et cosmochimica acta》2009,73(1):133-99
Sulfur- and oxygen-isotope analyses have been obtained for sediment-hosted stratiform barite deposits in Alaska, Nevada, Mexico, and China to examine the environment of formation of this deposit type. The barite is contained in sedimentary sequences as old as Late Neoproterozoic and as young as Mississippian. If previously published data for other localities are considered, sulfur- and oxygen-isotope data are now available for deposits spanning a host-rock age range of Late Neoproterozoic to Triassic. On a δ34S versus δ18O diagram, many deposits show linear or concave-upward trends that project down toward the isotopic composition of seawater sulfate. The trends suggest that barite formed from seawater sulfate that had been isotopically modified to varying degrees. The δ34S versus δ18O patterns resemble patterns that have been observed in the modern oceans in pore water sulfate and water column sulfate in some anoxic basins. However, the closest isotopic analog is barite mineralization that occurs at fluid seeps on modern continental margins. Thus the data favor genetic models for the deposits in which barium was delivered by seafloor seeps over models in which barium was delivered by sedimentation of pelagic organisms. The isotopic variations within the deposits appear to reflect bacterial sulfate reduction operating at different rates and possibly with different electron donors, oxygen isotope exchange between reduction intermediates and H2O, and sulfate availability. Because they are isotopically heterogeneous, sediment-hosted stratiform barite deposits are of limited value in reconstructing the isotopic composition of ancient seawater sulfate. 相似文献
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Estimation of structural damage from a known increase in the fundamental period of a structure after an earthquake or prediction of degradation of stiffness and strength for a known damage requires reliable correlations between these response functionals. This study proposes a modified Clough–Johnston single‐degree‐of‐freedom oscillator to establish these correlations in the case of a simple elasto‐plastic oscillator. It is assumed that the proposed oscillator closely models the response of a given multi‐degree‐of‐freedom system in its fundamental mode throughout the duration of the excitation. The proposed model considers the yield displacement level and ductility supply ratio‐related parameter as two input parameters which must be estimated over a narrow range of ductility supply ratio from a frequency degradation curve. This curve is to be identified from a set of recorded excitation and response time‐histories. Useful correlations of strength and stiffness degradation with damage have been obtained wherein a simple damage index based on maximum and yield displacements and ductility supply ratio has been considered. As an application, the proposed model has been used to demonstrate that ignoring the effects of aftershocks in the case of impulsive ground motions may lead to unsafe designs. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Poul V. Lade 《国际地质力学数值与分析法杂志》2006,30(4):307-333
Data from three‐dimensional experiments performed on sand in true triaxial equipment have been reviewed to sort out apparent disarray resulting from their interpretation. This has been done based on analyses made possible by recent developments and understanding of factors influencing sand behaviour: occurrence of shear banding, boundary conditions and/or specimen slenderness ratio, cross‐anisotropy, and stability of experimental technique. These factors are reviewed and test data from the literature are evaluated. Experimental data are divided into three groups in which: (a) homogeneous behaviour controls the sand strength; (b) shear banding affects the shape of the three‐dimensional failure surface in the midrange of values of b=(σ2?σ3)/(σ1?σ3), and (c) the data has been misinterpreted. Appropriate interpretation of three‐dimensional strength data for sand exhibiting isotropic, homogeneous behaviour is represented by a smoothly rounded triangular failure surface expressible in terms of the first and third stress invariants. Shear banding effects will cause the failure surface to be ‘indented’ in the midrange of b‐values in all sectors of the octahedral plane. Effects of cross‐anisotropy will result in lower strengths in sector III than in sector I of the octahedral plane, and the failure surface will appear as rotated around the stress origin in principal stress space. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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A rotational kinematic hardening constitutive model with the capability of predicting the behavior of soil during three‐dimensional stress reversals has been developed. An existing elasto‐plastic constitutive model, the Single Hardening Model, utilizing isotropic hardening serves as the basic framework in these formulations. The framework of the kinematic hardening model was discussed in a companion paper. The previously proposed cross‐anisotropic Single Hardening Model is added to the present kinematic hardening mechanism to capture inherent anisotropy of sands in addition to the stress reversals. This model involves 13 parameters, which can be determined from simple laboratory experiments, such as isotropic compression, drained triaxial compression and triaxial extension tests. The results from a series of true triaxial tests with large three‐dimensional stress reversals performed on medium dense cross‐anisotropic Santa Monica Beach sand are employed for comparison with predictions. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献