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91.
In this article, the possibility of sharing rain barrels and the potential benefit of reducing storage size through physical and non‐physical connections of rain barrels in a community are investigated. Using the concepts of homogeneous/heterogeneous users in rainwater harvesting systems (RWHS), two simple cases of a community composed of four prospective users are examined. The first is performed with the users who have the same mean and variance in water demands (homogeneous users), and the second is with the users with different means and variances (heterogeneous users). To take account for the rainfall characteristics in different places, historical records from six cities in the USA are used for storage–reliability–yield analysis. The result indicates that required total storage can be reduced by connecting multiple rain barrels. In addition, a significant difference is found between homogeneous and heterogeneous user groups. Homogeneous users do not achieve a substantial benefit from connecting their rain barrels; these users may even be disadvantaged by sharing. In contrast, heterogeneous users receive benefit by reducing the total required storage. Most benefit is expected between users with maximum difference in mean water demands. The reduction in storage size was as considerable as 37% in this study. The quantity of storage reduction depends on locations and target reliabilities. Knowledge of the benefits and limitations of rain barrel connections can improve RWHS performance through ability to customize a network plan for individual users. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
92.
Based on the theory of gravity‐driven groundwater flow systems, we have developed a complex Flow System Sand‐Box Model (FSM). It enables the visual observations of the development and characteristics and temporal evolution of complex Tóthian flow systems in the laboratory. The configuration of the regional, intermediate and local flow systems can be controlled and observed; hydraulic head, flow direction and travel time can be measured; and the scale and shape of the sub‐flow systems as well as the path lines and flow lines can be observed directly. The experiments demonstrate the Tóthian flow systems in a small basin with multiple sources and sinks. Greater local topographic (water table) undulation will lead to larger local flow systems. Greater regional and less local topographic undulation will enhance the development of intermediate and regional flow systems. In homogeneous media, increasing fluid‐potential differences between source and sink increase the spatial scale of the generated flow systems. The FSM is a useful teaching aid and experimental device to study and develop an intuitive insight into gravity‐driven groundwater flow systems. It helps to visualize and understand the hydraulic properties and controlling factors of Tóthian flow systems and may be used to study problems related to the chemical and temperature characteristics of the flow systems as well. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
93.
东海陆架盆地岩石密度与磁性 总被引:9,自引:0,他引:9
本文在东海陆架盆地20口钻井160块岩心标本物测定和17口钻井密度测井的基础上,通过整理、分析、统计,给出了东海陆架盆地的岩石密度和磁性特征。 相似文献
94.
Numerical Simulation of Andhra Severe Cyclone (2003): Model Sensitivity to the Boundary Layer and Convection Parameterization 总被引:1,自引:0,他引:1
C. V. Srinivas R. Venkatesan D. V. Bhaskar Rao D. Hari Prasad 《Pure and Applied Geophysics》2007,164(8-9):1465-1487
The Andhra severe cyclonic storm (2003) is simulated to study its evolution, structure, intensity and movement using the Penn
State/NCAR non-hydrostatic mesoscale atmospheric model MM5. The model is used with three interactive nested domains at 81,
27 and 9 km resolutions covering the Bay of Bengal and adjoining Indian Peninsula. The performance of the Planetary Boundary
Layer (PBL) and convective parameterization on the simulated features of the cyclone is studied by conducting sensitivity
experiments. Results indicate that while the boundary layer processes play a significant role in determining both the intensity
and movement, the convective processes especially control the movement of the model storm. The Mellor-Yamada scheme is found
to yield the most intensive cyclone. While the combination of Mellor-Yamada (MY) PBL and Kain-Fritsch 2 (KF2) convection schemes
gives the most intensive storm, the MRF PBL with KF2 convection scheme produces the best simulation in terms of intensity
and track. Results of the simulation with the combination of MRF scheme for PBL and KF2 for convection show the evolution
and major features of a mature tropical storm. The model has very nearly simulated the intensity of the storm though slightly
overpredicted. Simulated core vertical temperature structure, winds at different heights, vertical winds in and around the
core, vorticity and divergence fields at the lower and upper levels—all support the characteristics of a mature storm. The
model storm has moved towards the west of the observed track during the development phase although the location of the storm
in the initial and final phases agreed with the observations. The simulated rainfall distribution associated with the storm
agreed reasonably with observations. 相似文献
95.
直流电法在探测老窑采空区的应用 总被引:1,自引:1,他引:1
在各种工程地质、环境地质中、对地下采空区的探测是地球物理勘探的一项重要内容。文章从物性参数研究、技术方法择方面入手,探讨了直流电法探测老窑采空区的可行性,并以实例介绍了解决该问题所取得的经验。 相似文献
96.
本文提出了考虑各潜在震源相互耦合的等效物理模型,系统地建立了通过拟合各潜在震源地震序列来确定不同时间段内活断层形速率的方法,给出了预报各潜在震源未来一定年限内发生震级在不同震级段的概率模型。 相似文献
98.
99.
Koji Kameo Makoto Okada Moamen El-Masry Toshio Hisamitsu Saneatsu Saito Hiroomi Nakazato Naohiko Ohkouchi Minoru Ikehara Hisato Yasuda Hiroshi Kitazato Asahiko Taira 《Island Arc》2006,15(3):366-377
Abstract A continuous, well-preserved core was obtained from the Choshi area, on the Pacific side of Japan, to investigate paleoceanographic and paleoclimatic changes around the northwestern Pacific region during the middle Pleistocene. Siliciclastic sequences in the core are divided into five formations – the Obama, Yokone, Kurahashi and Toyosato Formations in the Inubo Group and the Katori Formation, in ascending order. Examination of calcareous nannofossils and magnetic polarities detected four datums in the core sediments of the Inubo Group: the top of Reticulofenestra asanoi , the base of Helicosphaera inversa , the top of Pseudoemiliania lacunosa and the Brunhes–Matuyama boundary. Fourteen marine isotope stages (MIS24–MIS11) were identified in the δ18 O and δ13 C records based on detected datums and the graphic correlation with the standard stack oxygen isotope curve. Magnetic susceptibility and gamma-ray attenuation porosity evaluator density were also measured and low values characterize the glacial intervals. Biogenic sedimentation by primary production may be larger during the glacial periods because of invasions of nutrient-rich northern surface-waters related to the southward shift of the Kuroshio front in the Choshi area. 相似文献
100.