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Coupled Hydrological/Hydraulic Modelling of River Restoration Impacts and Floodplain Hydrodynamics 下载免费PDF全文
H. M. Clilverd J. R. Thompson C. M. Heppell C. D. Sayer J. C. Axmacher 《河流研究与利用》2016,32(9):1927-1948
Channelization and embankment of rivers has led to major ecological degradation of aquatic habitats worldwide. River restoration can be used to restore favourable hydrological conditions for target species or processes. However, the effects of river restoration on hydraulic and hydrological processes are complex and are often difficult to determine because of the long‐term monitoring required before and after restoration works. Our study is based on rarely available, detailed pre‐restoration and post‐restoration hydrological data collected from a wet grassland meadow in Norfolk, UK, and provides important insights into the hydrological effects of river restoration. Groundwater hydrology and climate were monitored from 2007 to 2010. Based on our data, we developed coupled hydrological/hydraulic models of pre‐embankment and post‐embankment conditions using the MIKE‐SHE/MIKE 11 system. Simulated groundwater levels compared well with observed groundwater. Removal of the river embankments resulted in widespread floodplain inundation at high river flows (>1.7 m3 s?1) and frequent localized flooding at the river edge during smaller events (>0.6 m3 s?1). Subsequently, groundwater levels were higher and subsurface storage was greater. The restoration had a moderate effect on flood peak attenuation and improved free drainage to the river. Our results suggest that embankment removal can increase river–floodplain hydrological connectivity to form a more natural wetland ecotone, driven by frequent localized flood disturbance. This has important implications for the planning and management of river restoration projects that aim to enhance floodwater storage, floodplain species composition and biogeochemical cycling of nutrients. © 2016 The Authors. River Research and Applications Published by John Wiley & Sons Ltd. 相似文献
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贺江流域"2013.8"暴雨洪水期间,通过准确入库洪水预报,以贺江下游重要城镇安全泄洪量为控制,科学合理利用合面狮水库成功进行调蓄错峰,取得良好的防洪效果,分析了开展河库联合调度预报的技术路线及方法,为广泛开展河库联合调度预报服务提供参考及借鉴。 相似文献
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介绍了梧州市平浪防洪堤堤线、堤型的选择原则、思路,总体设计方案等基本情况。该设计方案融入可持续发展及生态水利的理念,将环保、人文以及可持续发展等贯彻于设计的全过程,体现了人与自然的和谐共处。 相似文献
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AbstractHere we describe the implementation of an experimental research tool called the Decision Game that we used to collect data on household flood risk management decisions. Participants using this tool play an interactive game that involves making household decisions about place of residence and a variety of household expenditures, including spending on flood insurance and private flood risk mitigation. Participants also answer survey questions before and after playing the game; the pre-game survey collected demographic information, and the post-game survey collected information about participant experiences with flooding and flood mitigation. Online and face-to-face participants showed similar engagement with the experiment, and most participants appeared to have made deliberate and considered decisions about risk mitigation. Online study participants had similar responses to those who participated in person, although face-to-face participants seemed slightly more likely to mitigate against risk. Overall, participants in this research were younger, more educated and more likely to rent a home than the average Canadian. Serious games may be useful for augmenting existing data gathering strategies used in understanding environmental decision making, particularly for rare catastrophic events for which stated preference surveys may be less informative. Serious games allow for sharing a mixture of information with study participants, including maps, video clips, text and even immersive 3D experiences, and can be administered online to increase participation levels. Future research will consider longer duration online experiments and more immersive interaction frameworks. 相似文献
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世界石油储量问题探析 总被引:1,自引:0,他引:1
储量决定声量,因而对石油储量问题的研究非常重要.与世界石油储量有关的问题有两个:一是当前的石油锗量有多少;二是未来储量会增长多少?本文认为:当前世界石油锗量为9000亿桶,未来储量增长,包括新发现的储量和现有油田的储量增长总共约专4700亿桶,二者相加.可计算出人类可以利用的石油总量还育137 00亿桶另外,人类已经生... 相似文献
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本文基于鄱阳湖洪水特点,选取特定洪水特征指标,利用数理统计方法分析鄱阳湖洪水特征指标的趋势性、突变性和周期性,并分析演变特征和驱动因素,得到结论如下:1)未来高洪可能性仍然较大,未来6~10a鄱阳湖年最高水位仍处于丰水期;2)洪水在年内分配发生较大改变,变化过程从“矮胖型”向相对“尖瘦型”演变,水量在年内更加集中化;3)高洪持续天数显著增加,19.00m以上的高水位维持时间平均每10a延长2.2d;4)年最高水位及年平均水位周期性变化主要受“五河”入湖周期性变化所控制,同时会受到其他因素影响而改变原有周期性变化规律,年最高水位具有5a为第一主周期,40~49a为第二主周期的变化规律。 相似文献
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瞬时单位线汇流参数m1非线性改进方法探讨 总被引:1,自引:0,他引:1
针对瞬时单位线计算设计洪水过程中,对单位线汇流参数m1进行非线性改进的运用条件和改进公式中采用的临界雨强等参数的取值等进行探讨. 相似文献
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柳州市防汛决策支持系统经过多年的建设已初具规模,但还存在一些问题,如防汛信息单一、结构不合理、设备潜力没有得以最大发挥等.因此,建立柳州市实时监测系统、水利三维可视化信息管理系统、抓紧进行防汛减灾指挥决策支持系统二期建设、加大对防汛信息资源的开发利用应是今后研究、探讨的主要问题. 相似文献