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Charles W. CARLSTON 《水文科学杂志》2013,58(3):62-84
ABSTRACT Sir Charles Cotton (1964) has pointed out that in an earlier paper (Carlston, 1963) which related drainage density to hydrology, there was insufficient emphasis on the role of climate in its effect on drainage density. Re-examination of the relation of drainage density to base flow in the 15 basins originally described has revealed additional evidence that base flow is affected by precipitation or recharge (a climatic variable), while varying inversely with drainage density. Within the climatic region studied in the earlier paper (the Humid Subtropical Climate of the eastern U. S.), no evidence could be found that amount or intensity of rainfall affected the intensity of flood runoff or the scale of drainage density. In comparison with other climates, however, such as the Marine West Coast Climate, it is possible that the less intense precipitation of a marine climate may result in lower runoff intensities and lower drainage densities, however the lower mean temperatures of such climates may develop soils of generally higher infiltration capacity which would produce lower drainage densities. A progressive increase in aridity results in a decrease in soil and vegetal cover which greatly magnifies the range of drainage densities characteristic of semi-arid regions. In such regions, where the land sur-face has a good infiltration capacity rainfall sinks readily into the dry soil (although recharge to ground water may be negligible), and runoff is virtually zero, as is drainage density, Impermeable terranes devoid of vegetal and soil cover reject the rain, runoff is briefly total and drainage density may be greatly magnified, as in the South Dakota Badlands, where drainage density runs into the hundreds. Arid or Desert Climates should produce erosional landforms with generally high drainage densities, though not reaching the magnitudes of drainage density found in the semi-arid badlands where rainfall intensities are much higher. 相似文献
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A. E. SCHEIDEGGER 《水文科学杂志》2013,58(4):87-92
Abstract It is shown that a thermodynamic analogy can be set up for structurally cyclic as well as for noncyclic river nets that satisfy Horton's law of stream numbers. In the latter case, the microcanonical formalism of statistical thermodynamics has to be used. 相似文献
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J. C. SCHÖNFELD 《水文科学杂志》2013,58(1):11-22
Abstract The intrusion of seawater in a tidal river is treated as a diffusion problem, characterized by a coefficient of longitudinal diffusivity. In order to analyse the longitudinal diffusivity, a mathematical model is set up, consisting of two bodies of water, either one besides the other or one on top of the other. The two bodies are assumed to move relatively to each other, as a secondary effect of the tidal flow. It is moreover assumed that there is turbulent exchange of salt between the bodies. It is demonstrated that the diffusion of salt into the river is greatest for an optimum value of the coefficient of exchange between the two bodies. Exchange weaker or stronger than this optimum both diminish the salt intrusion. The theory is applied to the Rotterdam Waterway, for which estimates of the exchange are made. Estimation of the reduction of the turbulence by stratification and hence of the vertical exchange, shows that the observed strong intrusion is explainable. Intensified vertical mixing, for instance as provoked by compressed air, need not always result in less intrusion, and hence should be considered carefully. 相似文献
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H. G. WILM 《水文科学杂志》2013,58(2):5-16
Synopsis A method of synthesis has been used to combine the variables characterising sediment transport in laboratory flumes into nondimensional functional equations. These equations are used to provide a basis for logical data correlations. By selecting appropriate nondimensional groups the effect of variation of individual variables such as flume width, sediment grain size, etc., can be determined. It has been found that work of this nature is hampered by the small amount of data available from rational experimentation. Much of the published data is unsuitable for direct use in correlations but may be of use in the future once the trend of results has been predicted by more limited but more basic data. When sufficient data for the transport of light weight materials is available correlations of the type presented may provide a secure basis for the choice of bed material for hydraulic models. 相似文献
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《国际地震动态》1989,(5)
授予菲利普.H.艾布尔森(Philip HaugeAbelson)的史密斯奖章是为纪念把毕生精力都献给了科学,特别是地球物理学的两位科学家而设立的。艾布尔森对科学的贡献,包括他个人的研究工作,任《科学》杂志编辑期间的卓越的工作,以及他曾任美国地球物理联合会会长等都是众人皆知的。但是人们可能还不太知道他在把《地球物理研究》(JGR)杂志创办成为美国地球物理联合会的主要杂志和世界主要的地球物理编年史中所起的作用。在50年代中期,随着国际地球物理年来临,美国地球物理联合会的成员可在诸如地震学会、美国气象学会、勘探地球物理学会之类的一些组织的专刊或美国地球物理联合会学报等专业杂志上发表文章。这些学报试图起到多 相似文献
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Dr. J. Georgi 《Pure and Applied Geophysics》1954,28(1):301-307
Zusammenfassung Die vonT. E. Aurén entwickelte Methode, aus einer grossen Anzahl von Messungen der Totalstrahlung der Sonne Kurven der mittleren Maxima zu gewinnen, wird befürwortet. Diese Kurven repräsentieren die für jeden Messort charakteristische, optimale Durchlässigkeit der Atmosphäre. Sie können daher auch als strahlungsklimatischer Parameter verstanden werden, sei es etwa als Intensität des solaren Strahlungsstromes bei bestimmten Höhenwinkeln, oder als Tagessummen usw. 相似文献
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《地震工程与工程振动(英文版)》2007,(4)
On November 16, 2007, George C. Lee, the editor-in-chief of our journal ?Earthquake Engineering and Engineering Vibration (EEEV), was among 11 people to receive a 2006 Presidential Award for Excellence in Science, Mathematics and 相似文献
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It is well known that the results of determining earthquake parameters depend to a large extent on data processing algorithms and velocity models of the seismic wave propagation medium used in solving hypocenter problems. In 1992, V.Yu. Burmin developed a hypocentric algorithm that minimizes the functional of distances between the points corresponding to the theoretical and observed travel times of seismic waves from an earthquake source to recording stations. The determination of the coordinates of earthquake hypocenters in this case is much more stable than for the commonly used minimization of the functional of discrepancies in the seismic wave arrival times at a station. Using this algorithm and the refined velocity model of the medium, V.Yu. Burmin and L.A. Shumlyanskaya reinterpreted the earthquake parameters for the Crimea–Black Sea region. The most important result of this reinterpretation was the conclusion about the occurrence of deep earthquakes with a source depth of more than 60 km in the region. This result contradicts the conventional beliefs about the seismicity of the region and therefore aroused strong criticism from experts directly involved in compiling the existing catalogs of regional earthquakes. These comments and criticisms are presented by V.E. Kulchitsky with coauthors in a work published in this issue of the journal. In the present paper, we analyze the comments in detail and respond. In particular, we show that the previously used methods of seismic data processing made it highly unlikely by default that deep earthquakes would appear in the results. As an example, we refer to the use of travel-time curves for depths down to 35 km. It is clear that deep earthquakes could not have been found with this approach. 相似文献
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R.C.框架结构的振动台试验和面向设计的时程分析方法 总被引：9，自引：1，他引：8
钢筋混凝土框架结构的弹塑性时程反应分析是抗震设计规范所要求的一项重要内容,但目前还滑有比较简单实用肯计算可靠的方法。本文进行了两个六层钢筋混凝土框架结构模型的地震模拟震动台试验,通过分析试验模型的自振特性、变形形式、加速度反应、位移反应和破坏开矿以及钢筋混凝土框架结构的实际震害,建立了面向设计的钢筋混凝土框架结构弹塑性里程反应分析的计算方法。在这一方法中,对钢筋混凝土框架整体结构采用层间剪切模型, 相似文献
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Zhang Shiqi 《国际泥沙研究》2000,(3)
Mr. Singh and Mr. Ghosh have carefully reviewed and made valuable suggestions and comments. Theauthor would like to express his gratitude to them. The explanations to the comments and some detailsof the model development are as follows.1 MATHEMATICAL MODEL ON SUSPENDED SEDIMENT TRANSPORTATIONThere are three types of models on sediment transportation, i.e. for simulating (1) bedload; (2)suspended sediment; and (3) all sediment including bedload and suspended sediment. In t… 相似文献
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Nachasova I. E. Pilipenko O. V. Markov G. P. Nedomolkina N. G. 《Izvestiya Physics of the Solid Earth》2020,56(2):238-248
Izvestiya, Physics of the Solid Earth - Abstract—The archaeomagnetic study of ceramic material from Veksa III archaeological site (φ = 59°17′ N, λ = 40°10′ E)... 相似文献
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《CT理论与应用研究》1991,(1)
在1989年召开的国际勘探地球物理北京学术讨论会上,苏联科学院西伯利亚分院地质与地球物理研究所戈尔丁(C. B. hon}guW教授做了地震C"I'的学术报告。会后,戈尔丁教授从苏 相似文献