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Poul L. Bjerg Kirsten Riigge Jesper Cortsen Per H. Nielsen Thomas H. Christensen 《Ground water》1999,37(1):113-121
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Eugenio Molina-Navarro Ryan T. Bailey Hans Estrup Andersen Hans Thodsen Anders Nielsen Seonggyu Park 《水文科学杂志》2019,64(4):434-454
In hydrological modelling of catchments, wherein streams are groundwater-fed, an accurate representation of groundwater processes and their interaction with surface water is crucial. With this purpose, a coupled model was recently developed linking SWAT (Soil and Water Assessment Tool) with the fully-distributed groundwater model MODFLOW (Modular Groundwater Flow). In this study, SWAT and SWAT-MODFLOW were applied to a Danish groundwater-dominant catchment, simulating groundwater abstraction scenarios and assessing the benefits and drawbacks of SWAT-MODFLOW. Both models demonstrated good performance. However, SWAT-MODFLOW provided more realistic outputs when simulating abstraction: the decrease in streamflow was similar to the volume of water abstracted, while in SWAT the impact was negligible. SWAT also showed impacts on streamflow only when abstractions were taken from the shallow aquifer, not from the deep aquifer. Overall, SWAT-MODFLOW demonstrated wider possibilities for groundwater analysis, providing more insights than SWAT in supporting decision making in relation to environmental assessment. 相似文献
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In the paper a recently proposed method for damage localization and quantification of RC-structures from response measurements is tested on experimental data. The method investigated requires at least one response measurement along the structures and the ground surface acceleration. Further, the two lowest time-varying eigenfrequencies of the structure must be identified. The data considered are sampled from a series of three RC-frame model tests performed at the structural laboratory at Aalborg University, Denmark during the autumn of 1996. The frames in the test series were exposed to two or three series of ground motions of increasing magnitude. After each of these runs the damage state of the frame was examined and each storey of the frame were classified into one of the following six classifications: undamaged, cracked, lightly damaged, damaged, severely damaged or collapse. During each of the ground motion events the storey accelerations were measured by accelerometers. After application of the last earthquake sequence to the structure the frames were cut into pieces and each of the beams and columns was statically tested and damage assessment was performed using the obtained stiffnesses. The damage in the storeys determined by the suggested method was then compared to the damage classification from the visual inspection as well as the static tests. It was found that especially in the cases where the damage is concentrated in a certain area of the structure a very good damage assessment is obtained using the suggested method. © 1998 John Wiley & Sons, Ltd. 相似文献
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Poul Degnbol Henrik Gislason Susan Hanna Svein Jentoft Jesper Raakjær Nielsen Sten Sverdrup-Jensen Douglas Clyde Wilson 《Marine Policy》2006
Fisheries management benefits from the contribution of several academic disciplines, each with their own perspectives, concerns and solutions. In this essay we argue that the contribution of biology, economics, sociology and other relevant disciplines to fisheries would be improved if they originated from broader, more integrated analytical perspectives that are attuned to the empirical realities of fisheries management. Today, disciplinary boundaries narrow the perspectives of fisheries management, creating tunnel vision and standardized technical fixes to complex and diverse management problems. Having worked separately and together for a number of years in fisheries research and consultancy in many parts of the world we, as a group of biologists, economists and sociologists, feel that the time to rid ourselves from disciplinary dogmatism is long overdue. We claim that improvements in fisheries management will be realized not through the promotion of technical fixes but instead by embracing and responding to the complexity of the management problem. 相似文献