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71.
72.
Jim Whitman 《GeoJournal》1994,34(2):167-175
In the Post-Cold War environment, the role of the military has been extended to include intra-state peace enforcement on humanitarian grounds. This raises issues of legality. In this paper, four arguments are advanced that a right of states to intervene in humanitarian emergencies now exists. Problems contingent upon such intervention are then examined. 相似文献
73.
The simple Lanczos method presented in a recent paper by the writers, with application to single vector loads, is extended to include a more general dynamic loading represented as a linear combination of k vectors (load patterns). The result is a set of orthogonal vectors that is used to transform the equations of motion to a banded form, the half-bandwidth of which becomes k + 1. When k is small relative to the number of equations, this approach provides for a very efficient time-stepping solution. 相似文献
74.
The magnitude M = 6-5 Coalinga earthquake of 2 May 1983 caused intense ground shaking throughout the epicentral region. Unanchored cylindrical ground supported tanks located at six sites within this oil producing area were damaged; damages included elephant's foot buckling at the base of three moderate sized tanks, joint rupture and top shell buckling in one large old rivetted tank, bottom plate rupture of a relatively new welded tank and damage to the floating roofs of 11 tanks. Also oil spilled over the top of many tanks and secondary damages occurred in pipe connections, ladders, etc. In this paper an estimate is made of the intensity of ground motion at each of the tank sites, based on strong motion records made during the main shock and the strongest aftershock. Then response parameters specified by current codes are correlated with the damages observed at each tank site. Based on this comparison, it is concluded that current U.S. practice under-estimates the sloshing response of tanks with floating roofs and does not adequately address the uplifting mechanism of unanchored ground supported tanks. 相似文献
75.
The concentration and areal distribution of selected trace metals (Cu, Zn, Pb, Cd, Mo, Ni, Mn and Hg) in surficial sediments of Saint John Harbour, New Brunswick, Canada, were studied to determine the extent of anthropogenic input and to estimate the effects of dumping dredged material in the outer harbour. Hg and Cd are of especial concern, since the disposal of dredge material containing these two elements is regulated under the Ocean Dumping Control Act.The concentrations of all metals are low: Cu 16, Zn 53, Pb 24, Cd 0.16, Mo 3, Ni 16, Mn 296 and Hg 0.04 μg g?1. Hg and Cd levels in sediments are well below the permissible limits of 0.75 and 0.6 μg g?1, respectively, set by the Ocean Dumping Control Act.The mean concentrations of trace elements are similar to the low mean values in the unpolluted Bay of Fundy. There is an overall decline in concentrations of metals in the sediments from the inner to the outer harbour. Comparison of the metal levels in the sediments from different areas within the harbour indicate that there is a detectable anthropogenic input in the Courtenay Bay area. Trace metal levels at the dumpsite are significantly lower than in the Courtenay Bay area, where the bulk of the dredged material originates. 相似文献
76.
D.K. Paul P. Kresten T. Ray Barman R.H. McNutt A.O. Brunfelt 《Journal of Volcanology and Geothermal Research》1984,21(1-2)
Petrographic and geochemical data are given for some basaltic rocks from the Koynaghat, Ambaghat and Panvel sections of the western Deccan volcanic province. This study confirms geochemical features established earlier for the Deccan basalts but brings out minor additional characters. Mineralogical and major-element compositions of the basaltic flows from the Koyna and Panvel sections indicate tholeiitic affinity; the Ambaghat flows exhibit a slight affinity towards alkali basalt. Rare earth element (REE) distribution patterns and trace-element abundances suggest minor fractionation of olivine and plagioclase during the evolution of the flows. The general similarity of chemical and mineralogical features over a wide area and the lack of conspicuous inter-element relationships suggest that the flows reflect the combined effects of partial melting, minor mineral fractionation and selective crustal contamination. 相似文献
77.
Durga Ray 《Boundary-Layer Meteorology》1986,36(1-2):117-131
Using variable atmospheric eddy diffusivities, it is possible to obtain a theoretical explanation of observations concerning the increase of cell flatness in cellular cloud patterns. The inclusion of a horizontal variation of eddy size as proposed by Ray (1965) and supported by Agee (1973) has a large influence on theoretical Rayleigh number and cell shape, the degree of cell flatness being principally controlled by the degree of horizontal variation of the eddies. It is also shown that observations regarding the reversal of the circulation pattern could be interpreted on the basis of eddy diffusivities that change sign along the reference directions. This suggests that it may be useful to rethink our ideas about the existence of spatial variations in the eddy transfer coefficients in atmospheric convection. 相似文献
78.
L. Alados-Arboledas J. I. Jiménez Y. Castro-Díez 《Theoretical and Applied Climatology》1986,37(1-2):84-89
Summary Data on thermal radiation from clear skies obtained at Granada from May to November 1983 were utilized to carry out a detailed comparison between measured and calculated values of longwave radiation with several analytical and empirical equations. The goal of this work is to check the aplicability of these equations to Granada conditions. The results obtained for all the equations are quite satisfactory. Nevertheless, Idso's formula significantly overestimates our experimental results, probably as a consequence of the differences in atmospheric dust conditions between our test area and the location for which that equation was originally derived. A reduction in the independent coefficient, in accordance with previous results of other authors, provides a better fit to our data set and clearly shows the climatological dependence of the constants in the estimation equations.
With 3 Figures 相似文献
Zusammenfassung Die von Mai bis November 1983 in Granada gesammelten Daten über Wärmestrahlung bei klarem Himmel wurden dazu verwendet, um einen detaillierten Vergleich zwischen gemessenen und errechneten Werten der langwelligen Strahlung aus verschiedenen analytischen und empirischen Gleichungen durchzuführen. Das Ziel dieser Arbeit ist es, die Anwendbarkeit dieser Gleichungen auf die Verhältnisse in Granada zu überprüfen. Die gewonnenen Ergebnisse sind für alle diese Gleichungen ganz zufriedenstellend. Idsos Formel überschätzt jedoch deutlich unsere experimentellen Ergebnisse, möglicherweise als Folge der unterschiedlichen atmosphärischen Staubbedingungen in unserem Testgebiet und dem Standort, für den die Gleichung ursprünglich abgeleitet wurde. Eine Reduktion des unabhängigen Koeffizienten, in Übereinstimmung mit früheren Ergebnissen anderer Autoren, bietet eine bessere Anpassung an unseren Datensatz und zeigt deutlich die klimatologische Abhängigkeit der Konstanten in Schätzungsgleichungen.
With 3 Figures 相似文献
79.
Jim C. Loftis Jane Harris Robert H. Montgomery 《Ground Water Monitoring & Remediation》1987,7(1):72-76
The Resource Conservation and Recovery Act (PL 94–580) and related federal and state legislation have mandated routine monitoring of ground water quality at regulated facilities. The objective of the required monitoring activities is detection of adverse changes in ground water quality caused by the facilities.
Both failure to detect pollution and an incorrect determination of pollution can be very expensive. It is crucial, therefore, that monitoring programs be designed and operated to provide statistically sound information. It is equally important that users of ground water quality data understand the nature and limitations of information from monitoring.
To address the preceding issues, the authors present a general approach to analyzing ground water quality data in light of the stated monitoring objective. The suggested approach accounts for "natural" variation in background water quality through pairing of observations. The limitations of quarterly sampling for detecting small changes in quality over a short time frame are discussed. 相似文献
Both failure to detect pollution and an incorrect determination of pollution can be very expensive. It is crucial, therefore, that monitoring programs be designed and operated to provide statistically sound information. It is equally important that users of ground water quality data understand the nature and limitations of information from monitoring.
To address the preceding issues, the authors present a general approach to analyzing ground water quality data in light of the stated monitoring objective. The suggested approach accounts for "natural" variation in background water quality through pairing of observations. The limitations of quarterly sampling for detecting small changes in quality over a short time frame are discussed. 相似文献
80.
A dynamic response analysis procedure for an x-braced tubular steel offshore platform frame is described, including details of the mathematical model adopted to represent the dynamic buckling behaviour of the brace member. Results obtained with this mathematical technique are compared with experimental data measured during shaking table tests of a 5/48 scale model frame. The agreement between experiment and analysis is excellent for different levels of response, ranging from linearly elastic to cyclic brace buckling. 相似文献