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Nearshore water circulation and bar patterns at Coledale, New South Wales, were surveyed daily over thirty-six consecutive days, from 3 November to 8 December 1978, to identify sequences of changes that might occur in response to spring-to-spring tide cycles of fourteen days, changing barometric and wind conditions associated with the passage of anticyclonic weather systems across the coast, and day to day variation in the nearshore wave regime. During the survey the bar patterns tended to vary from transverse bars, through a composite arrangement incorporating longshore and transverse bars, to a longshore bar pattern as the tide changed from its spring to neap tide phase. However, this sequence was too brief to unequivocally establish variations in nearshore bar pattern that might be attributed to the fourteen day, spring-to-spring tide cycle. Nevertheless, morphologic changes occurring in response to wave regime fluctuation at Coledale were broadly in accord with studies from elsewhere by Dolan et al. (1979, 1982), and Clarke and Eliot (1982, 1983) in that bars and rips were systematically distributed along the beach. At Coledale, bars tended to relocate approximately 0.4 and 0.75 of the distance along the beach from its southern end. The preferred bar spacing closely matches hypothetical standing waves trapped between the headlands of the Coledale embayment. Temporally, the nearshore morphology is highly responsive to wave regime changes such that, as primary breaker heights decrease and remain below Hmax=1.0m, the bar pattern changes from longshore through mixed to transverse bar patterns within three to five days. On one occasion the bar pattern switched from a longshore to a transverse bar pattern within twenty-four hours.  相似文献   
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The Multiregional Variable Input-Output (MRVIO) model is introduced to measure the development impact of a transportation system. The MRVIO model is a theoretically flexible, computationally simple, and cost-responsive model. Under the MRVIO model, regional input-output coefficients, trade coefficients, and trade flows become cost responsive and easy to compute. The MRVIO model is employed to measure the development impact of the Arkansas waterway during the period of 1974 to 1978. In the study, the U.S. economy is disaggregated into 3 regions and 35 industrial sectors. The MRVIO model estimates the economic conditions of these 3 regions with and without the waterway in terms of industrial output, income, employment, and trade flows.  相似文献   
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Book reviews     
Derek McDougall, Harold D. Lasswell and the Study of International Relations. University Press of America, Lanham, USA, 1984, pp.370. $16.50.

John W. Burton, Global Conflict: The Domestic Sources of International Crisis. Wheatsheaf Books, UK, 1984, pp.194. $54.00.

K.J. Holsti, The Dividing Discipline: Hegemony and Diversity in International Theory. Allen and Unwin, Boston and Sydney, 1985. pp.165. $39.95.

Hedley Bull (ed.), Intervention in World Politics. Clarendon Press, Oxford, 1984, pp. viii + 198. $31.00.

Hedley Bull, Justice in International Relations. 1983–84 Hagey Lectures, University of Waterloo, 1984, pp. iii + 36. No price given. (Available from University Publications Distribution Service, Dana Porter Arts Library, University of Waterloo, Waterloo, Ontario N2L3G1, Canada.)

Benedict Anderson, Imagined Communities: Reflections on the Origin and Spread of Nationalism. Verso Editions and NLB, London, 1983, pp. 160. £15.00.

Chalmers Johnson, Revolutionary Change. Second edition. Longman, London, 1983, pp.xii + 217. $13.85.

Peter Calvert, Politics, Power and Revolution. An Introduction to Comparative Politics. Wheatsheaf Books, Brighton, 1983, pp.208. £5.95.

John Walton, Reluctant Rebels. Comparative Studies of Revolution and Underdevelopment. Columbia University Press, New York, 1984, pp.xii + 230 $US36.00 (cloth), $US10.00 (paper).

E. A. Tiryakian and R. Rogowski (eds), New Nationalisms of the Developed West. Toward Explanation. Allen and Unwin, Boston, 1985, pp.xii + 394. $69.00.

Peter H. Merkl and Ninian Smart (eds), Religion and Politics in the Modern World. New York University Press, New York, 1985, pp.276. No price given.

Richard Lowenthal, Social Change and Cultural Crisis. Columbia University Press, New York, 1984, pp.viii + 252. $US29.50.

Dietrich Fischer, Preventing War in the Nuclear Age. Rowman and Allanheld, Totowa, N.J./Croom Helm, London, 1984, pp. x + 236. $27.95.

F. Dyson, Weapons and Hope Harper and Row, New York, 1984, pp.340. $24.95.

John Langmore and David Peetz (eds), Wealth, Poverty and Survival. Australia in the World. George Allen and Unwin, Sydney, in association with the Australian Labor Party, 1983, pp. 225.  相似文献   

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ABSTRACT. The intertemporal structure of regional nominal-wage differentials by race is estimated using panel data from 1973 through 1978. This allows for a more complete analysis of the time pattern of changes in wage differentials, which is not possible from cross-sectional studies. The findings indicate that, in addition to the presence of substantial locational differentials, there was a systematic change in the differentials over time.  相似文献   
118.
ABSTRACT This paper develops a model of regional financial markets which can encompass different degrees of spatial financial integration. The behavior of the system is analyzed under alternative assumptions about the time frame of analysis and the extent of the flexibility of interest rates. It is argued that links may exist between regional real and financial sectors even in the short run and that such links must, through the regional balance of payments, exist in the long run, even where there is perfect financial spatial integration. It is observed that these relationships have generally been ignored by regional economic model builders.  相似文献   
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