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Brendon A. Bradley 《地震工程与结构动力学》2010,39(12):1321-1342
A generalized conditional intensity measure (GCIM) approach is proposed for use in the holistic selection of ground motions for any form of seismic response analysis. The essence of the method is the construction of the multivariate distribution of any set of ground‐motion intensity measures conditioned on the occurrence of a specific ground‐motion intensity measure (commonly obtained from probabilistic seismic hazard analysis). The approach therefore allows any number of ground‐motion intensity measures identified as important in a particular seismic response problem to be considered. A holistic method of ground‐motion selection is also proposed based on the statistical comparison, for each intensity measure, of the empirical distribution of the ground‐motion suite with the ‘target’ GCIM distribution. A simple procedure to estimate the magnitude of potential bias in the results of seismic response analyses when the ground‐motion suite does not conform to the GCIM distribution is also demonstrated. The combination of these three features of the approach make it entirely holistic in that: any level of complexity in ground‐motion selection for any seismic response analysis can be exercised; users explicitly understand the simplifications made in the selected suite of ground motions; and an approximate estimate of any bias associated with such simplifications is obtained. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
954.
Abstract The Blaney-Criddle (BC) temperature-based equation is used in areas where the complete weather data to estimate reference evapotranspiration (ET0) by the Penman-Monteith FAO-56 (PMF-56) standard model is complex. In this study, the BC equation was first tested and calibrated against the ET0 values computed by the PMF-56 method using data from 17 weather stations in arid regions of Iran. Then, geographical information systems (GIS)-based spatially-distributed maps of ET0 were prepared by means of geographic/topographic factors derived from a digital elevation model (DEM) for all months, separately. The results indicate that the original BC equation overestimated PMF-56 ET0 by 4% at the study sites. The BC equation produced closer ET0 estimates to the PMF-56 method after it was calibrated. The error rate of <3% for the spatial modelling approach suggests that the developed ET0 maps are reliable. Editor D. Koutsoyiannis; Associate editor D. Yang Citation Tabari, H., Hosseinzadeh Talaee, P., and Shifteh Some'e, B., 2013. Spatial modelling of reference evapotranspiration using adjusted Blaney-Criddle equation in an arid environment. Hydrological Sciences Journal, 58 (2), 408–420. 相似文献
955.
Despite significant technological advances in emerging economies, the further development of clean energy technologies in developing countries remains crucial to reducing the greenhouse gas emissions associated with economic development. In this paper we address two significant gaps in the growing body of literature that has assessed the role of the Clean Development Mechanism in promoting the transfer of clean technologies to developing countries. First, we present a qualitative analysis of the governance of the Clean Development Mechanism in India. This provides a basis for understanding the extent to which and the ways in which governance may impact upon the likelihood that projects promote technology transfer. Second, we provide a novel quantification of the level and nature of technology transfer that has occurred in Indian Clean Development Mechanism projects, based on insights from literature on technological capability building. We find that the Clean Development Mechanism in India has produced a negligible number of projects that promote technology transfer if technology transfer is understood as a process of learning about technology. Together these qualitative and quantitative analyses show how politics and governance have contributed to the current form of the Clean Development Mechanism market in India, in which processes of building indigenous technological capabilities have been neglected. 相似文献
956.
In recent years, Moso bamboo (Phyllostachys pubescens) forests have rapidly expanded in Japan by replacing surrounding coniferous and/or broadleaved forests. To evaluate the change in water yield from forested areas because of this replacement, it is necessary to examine evapotranspiration for Moso bamboo forests. However, canopy interception loss, one of the major components of evapotranspiration in forested areas, has been observed in only two Moso bamboo forests in Japan with relatively high stem density (~7000 stems/ha). There are, in fact, many Moso bamboo forests with much lower stem density. Thus, we made precipitation (Pr), throughfall (Tf) and stemflow (Sf) observations for 1 year in a Moso bamboo forest with stem density of 3611 stems/ha and quantified canopy interception loss (Ic). Pr and Ic for the experimental period were 1636 and 166 mm, respectively, and Ic/Pr was 10%. The value was approximately the same as values for the other two Moso bamboo forests and lower than values for coniferous and broadleaved forests. On the other hand, Tf/Pr and Sf/Pr for our forest (86% and 4%, respectively) were approximately 10% of Pr larger and smaller than values for the other two Moso bamboo forests. These results suggest that the difference in stem density greatly affects precipitation partitioning (i.e. Tf/Pr and Sf/Pr) but does not greatly change Ic/Pr. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
957.
Combined open channel flow is encountered in many hydraulic engineering structures and processes, such as irrigation ditches and wastewater treatment facilities. Extensive experimental studies have conducted to investigate combined flow characteristics. Nevertheless, there is no simple relationship that can fully describe the velocity profiles in a turbulent flow. The artificial neural network (ANN) has great computational capability for solving various complex problems, such as function approximation. The main objective of this study is to evaluate the applicability of the ANN for simulating velocity profiles, velocity contours and estimating the discharges accordingly. The velocity profiles measured by an acoustic doppler velocimeter in the open channel of the Chihtan purification plant, Taipei, with different discharges at fixed measuring section and different depths are presented. The total number of data sets is 640 and the data sets are split into two subsets, i.e. training and validation sets. The backpropagation algorithm is used to construct the neural network. The results demonstrate that the velocity profiles can be modelled by the ANN, and the ANN constructed can nicely fit the velocity profiles and can precisely predict the discharges for the conditions investigated. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
958.
Statistical tests and error analysis of cloud drift winds(CDWs) from the FY-2C satellite were made by using radiosonde observations.According to the error characteristics of the CDW,a bias correction using the thermal wind theory was applied in the data quality control.The CDW data were then assimilated into the GRAPES-meso model via the GRAPES-3DVar.A torrential rain event that occurred in northwestern China during 1-2 July 2005 was simulated.The results indicate that the CDW data were mainly distribute... 相似文献
959.
《水文科学杂志》2013,58(2)
Résumé Des mesures hydrométriques classiques et l'imagerie 2-D de résistivité électrique (IRE) détaillée ont été combinées avec le prélèvement de traceurs pour identifier les processus hydrologiques en jeu dans un bassin versant semi-aride de la province Cap-Oriental, en Afrique du Sud. L'étude des événements de précipitation et d'écoulement a souligné la forte relation qui existe entre les précipitations et les caractéristiques de la génération des écoulements. L'observation du potentiel hydrique du sol ainsi que du niveau d'eau souterraine a mis en évidence le développement d'une nappe perchée dans le sol. Ces résultats sont confirmés par des séparations d'hydrogrammes à base de traceurs et illustrent le rôle important des écoulements souterrains superficiels. L'étude par IRE a permis de mieux connaître la structure du sous-sol. Finalement, l'étude par IRE, combinée avec des mesures obtenues par réflectométrie en domaine temporel (TDR), a permis d'extrapoler à des mesures sélectives de teneur en eau. Pour récapituler, l'utilisation et la combinaison de différentes méthodes de terrain ont mené au développement d'un modèle conceptuel du fonctionnement hydrologique de ce bassin versant. Le rôle dominant des mécanismes de subsurface a été démontré. 相似文献
960.
This paper describes the hydrological changes caused by inter‐basin water transfer and the reservoir development on the hydrological regimes of two rivers. The Sabljaki Reservoir in the Zagorska Mre?nica River and the Bukovik Reservoir in the upper Dobra River began operation in 1959. Both are part of the hydroelectric power plant (HEPP) Gojak, whose installed capacity is 50 m3/s. Their water volumes at the spillway altitudes of 320·10 and 320·15 m a. s. l. are 3·3 × 106 and 0·24 × 106 m3 respectively. Both the Dobra and Mre?nica Rivers are losing, sinking and underground karst rivers. A 9376‐m‐long tunnel provides water from the Sabljaki Reservoir to the HEPP Gojak, which was constructed in the Lower Dobra River. The Sabljaki Reservoir is located in the Pla?ki karst polje, while the Bukovik Reservoir is located in the neighbouring Ogulin karst polje. The consequences of the inter‐basin water transfer are strong and have caused abrupt changes in the hydrological regimes of the downstream sections of both rivers. At the same time, the construction and development of both the reservoirs have also caused hydrological changes to the upstream section of the Upper Dobra River. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献