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71.
A key area in the analysis of urban structural evolution is identifying discontinuities. Effective analysis could improve long‐term forecasting and provide a better understanding of how to steer an urban system toward a desirable future state. We use a simple aggregate retail model to demonstrate an algorithm for identifying discontinuities in model parameter space. Explorations of retailing in both Greater London and South Yorkshire in the United Kingdom illustrate how understanding a system's potential for discontinuity can provide insights for both policy makers and retail businesses. The Harris and Wilson model, described in the section so‐named, is used as a simple archetype to illustrate the new framework. This model can be developed in a straightforward way to incorporate further refinement. In “ Executing the model and visualizing the results ,” we describe a single model run and in “ Investigating discontinuities ,” we explain our framework for detecting and analyzing discontinuities. “ Identifying discontinuities in the London retail system ” shows the results of applying this methodology to the Greater London retail system, and in “ Practical applications ,” we explore the policy applications for this technique as related to the decline of town centers in the South Yorkshire retail system. Some concluding comments are offered in “ Conclusions .”  相似文献   
72.
73.
Since 2005, a burgeoning wave of Chinese investments has set off a new ‘minerals boom’ in the Australian iron ore and coal mining sectors. While normally a welcome development, the state-owned and strategic nature of the investors has raised concerns in Australia about how these should be regulated. As a result, in February 2008 the Australian government declared an intention to more closely screen foreign direct investment (FDI) from state-owned sources, which both supporters and detractors alike have claimed is evidence of ‘resource nationalism’ in Australia's approach towards its trade and investment relationships with China. This article challenges this understanding through an examination of the characteristics of Chinese mining FDI, the dilemmas these present to the Australian government, and the relatively restrained nature of its response. Through this, Australia's FDI policy is explained as a defensive move against the potential for strategic behaviour by Chinese investors resulting from their state ownership, rather than any national program to subject minerals trade and investment to political control. On this basis, the article argues that Australian government policy instead evidences a ‘resource liberalism’ approach, which intends to ensure that the governance of Australia's minerals trade and investment with China remain market-based processes.  相似文献   
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75.
This paper examines two different bill of rights models for Australia: the Dialogue model and a Democratic model. The Dialogue model aims to protect rights through a bill of rights, strong political review mechanisms, intergovernmental dialogue, and rights-based judicial review. The paper argues that, despite its popularity, there are serious problems with the legitimacy and effectiveness of the Dialogue model and it outlines an alternative model, a ‘democratic bill of rights’, which attempts to avoid these problems by strengthening democratic institutions and political review mechanisms without adopting rights-based judicial review. The paper concludes that a democratic bill of rights is likely to be an effective and more democratically legitimate way of protecting and promoting human rights in Australia.  相似文献   
76.
The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River. The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001. 160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and 7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10th–15th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing standard chronology or to create a long floating average treering curve.  相似文献   
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EUROPE

France; A Geographical Survey. By P. Pinchemel, translated by C. Trollope and A. J. Hunt. 454 pp. Illustrations, Tables, Bibliography. Bell, London, 1969. 100s.

Italy. By George Kish. 8 × 5 1/4. 125 pp. 12 figures and index. Van Nostrand, New York, 1969. $1.lb95.

AFRICA

A Historical Geography of Ghana. By Kwamima B. Dickson. 15#lb5 × 23.lb5 cms. xiv + 379 pp., 58 maps and diagrams, 7 tables, appendices, bibliography, index. Cambridge U.P., London, 1969. 150s.

The Soil Resources of Tropical Africa. Edited by R. P. Moss. 8 1/2 × 5 1/2. Cambridge University Press, 1968. £2.

ASIA

Afghanistan. By Ludolph Fischer. Geomedical Monograph Series No. 2, 12 × 8 1/2. Text (German and English), 16 plates and 10 maps. Springer‐Verlag, Berlin, Heidelberg and New York, 1968. DM48, $12.lb00.

GEOLOGY AND GEOMORPHOLOGY

Readings in the Earth Sciences, Vols. 1 and 2. 11 1/4 × 8 1/2 Published W. H. Freeman, San Francisco, 1969. 94s. each.

Fife and Angus Geology. By A. R. MacGregor. 266 pp. Blackwood, Edinburgh and London, 1968. 21s.

METEOROLOGY

Essentials of Meteorology. By D. H. McIntosh and A. S. Thorn. 8 1/2 × 5 1/2. xv + 239 pp., numerous illustrations, answers to problems. Taylor and Francis, London. 20s.

ECONOMIC GEOGRAPHY

Industrial Britain: The North West. By David M. Smith. 10 × 6 1/4, 271 pp., 36 figures, 31 plates, bibliography and statistical appendix. David and Charles, Newton Abbot, 1969. 95s.

Industrial Demand for Water: A study of South East England. By Judith Anne Rees. 8 1/2 × 5 1/2 L.S.E. Research Monographs 3, xiv + 194 pp., Weidenfeld and Nicolson, 1969, London. 65s.

CARTOGRAPHY AND MAPS

The Antonine Wall. Ordnance Survey 2 1/2 Inch Map. 1969. 11s.

Maps and Air Photographs. By G. C. Dickinson. 10 × 17 1/2. xiv + 286 pp. Edward Arnold, London, 1969. 45s.

Atlas Four. 10 1/2 × 8 1/2. 115pages, + index 60 pages. Collins/Longmans, 1969. 15s.

EDUCATIONAL

Learning Through the Environment. By Muriel F. S. Hopkins. 7 3/4 × 5 1/8. 151 pages, 26 figures. Longmans, London. 1969. 15s.

Investigating Geography. By J. Philip Dodd. 9 3/4 × 7 1/4. 214 pp., 192 figures. Heinemann, London, 1969. 15s.

The London Regional Geographies. Book 3: Asia. By Leonard Hadlow and Reginald Abbott. 8 1/2 × 5 1/2. 294 pp., 145 figs. U. of London Press, 1969. 18s.

A Geography of Manufacturing. By H. R. Jarrett. 8 3/4 × 5 3/4. xvii + 349 pp. 67 illustrations. Macdonald &; Evans, 1969, London. 35s.

The Mediterranean Lands. By J. Brannigan and H. R. Jarrett. The New Certificate Geography Series: Advanced Level. 9 × 5l. xiv + 620, 150 illustrations. Macdonald and Evans Ltd., 1969. 38s.  相似文献   
79.
The Scottish Executive has adopted a policy to combat Scotland's declining population by encouraging inward migration. Using a multi‐state population model this paper presents nine long‐term population scenarios for Scotland using three net international migration levels and three fertility paths. The results show inward migration can slow population decline but makes little difference to population ageing. Without a higher fertility rate Scotland's population will become demographically unsustainable. Our simulations show that a higher fertility rate substantially reduces the future ageing.  相似文献   
80.
During the late‐Midlandian (25–13 14C ka BP), the last Irish Ice Sheet was thicker in the Western Mourne Mountains than previously argued. Geomorphological and sedimento‐logical analysis shows that regional ice from the Irish Ice Sheet spilled over the mountains, reaching a major limit 5 km along Pigeon Rock Valley. These findings differ from the previous view that a local valley glacier occupied the valley during this period. The pattern of deglaciation was reconstructed using glacial and periglacial evidence. A complex topographic environment in the upper reaches of the valley suggests that regional ice stagnated as it wasted away. During the Nahanagan Stadial (Younger Dryas, ca. 11–10 ka 14C BP) an arcuate ridge was formed on the western flank of the valley. Calculations suggest that the Equilibrium Line Altitude, influenced by topographic conditions favourable for snow accumulation, was approximately between 1736 m and 1386 m lower during the Nahanagan Stadial than at present.  相似文献   
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