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1.
江西省防汛PDA应用系统设计 总被引:1,自引:0,他引:1
防汛PDA系统采用B/S和C/S相结合的构架方式,通过GPRS网络平台,能够清晰而灵活的显示出各种防汛工作所需的信息,为防汛工作者提供了全方位的移动指挥办公手段. 相似文献
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鄱阳湖流域水土流失加剧了洪涝灾害。治理水土流失能增强山丘地涵养水源的能力,削洪减沙,减少库容损失,降低河床,具有明显的防洪效益。进行流域防洪规划时,应将防治水土流失与防洪治涝结合起来,因地制宣,综合治理。 相似文献
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A list of 196 Coleoptera taxa, larvae and adults, covering 113 species, was obtained from several surveys of a flood plain of the Rhô river. From published reports and personal experience, each taxon is linked with the modalities of nine environmental and three biological variables. The resulting 12 ecological profiles for 196 taxa are analysed by correspondence analysis. The simultaneous ordination of the taxa and variables allows presentation of the more synthetic correspondence between the Coleoptera and their ecological and biological characteristics. The niche dimensions of the 12 variables tested here are organized along a current-substrate gradient, from stones in rapid flow to mud in still water, which is associated with the other ecological conditions. This ordination reflects environmental conditions in a transverse direction, particularly from the central channel to the furthest annexes of the river. The Coleoptera are shown to be describers of the connectivity with the main channel. The 196 studied taxa are positioned along the gradient. They are subdivided into seven faunal groups based on their habitat range or niche width. The larger species are confined to the stagnant side of the gradient. Other variables, such as feeding and vertical distribution, clearly separate carnivores from herbivores and also larvae from adults. The next step of this study will be to extend these investigations to other functional variables and to all the species of Coleoptera in France. The information given by the Coleoptera will then be compared with actual field measurements. 相似文献
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预报预警是山洪灾害防治中重要的非工程措施,是防灾减灾救灾的关键环节。选取分别代表秦巴山地水资源保护区、西南地震作用区、喀斯特地区、黄土高原超渗产流区、东南沿海台风影响区的湖北省丹江口官山河流域、四川省都江堰白沙河流域、贵州省望谟县望谟河流域、陕西省子洲县岔巴沟流域、广东省高州市马贵河流域这5个典型流域,通过构建改进的SCS模型进行历史山洪模拟,探讨该模型在小流域暴雨山洪预报预警中的广泛适用性。结果表明:基于SCS模型构建的小流域暴雨山洪预报方案中官山河、白沙河、望谟河、马贵河方案均为乙级方案,可用于正式发布预报;岔巴沟为丙级方案,可用于参考性预报。SCS模型在5个典型示范区的洪峰流量预报精度普遍在80%左右,高于我国山洪灾害洪峰流量预报平均水平(40%)。总体来说,SCS模型对各类典型流域的山洪模拟效果较好,能够用于山洪灾害预报预警业务。SCS模型结构简单,参数少,特别适用于无资料地区推广应用。 相似文献
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本文通过对赣江流域袁河“82·6”和“89·7”两次大洪水的分析比较,得出结论:准确的水情预报和水库工程正确的调度方式,能减轻下游防洪负担,最大限度地减少洪灾损失,夺取抗洪斗争的胜利。文中提醒人们,在防汛工作中,应把非工程措施提高到相当的地位来加以重视。 相似文献
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年最大洪峰流量预测,受较多的复杂因素的影响,不确定性较强,用常规统计方法做出准确预报具有较大困难。从水文序列本身出发,提出将投影回归模型应用于年最大洪峰流量预测,为了更好获得投影寻踪模型参数和预测精度,提出了运用延迟相关系数法确定回归预测因子、群居蜘蛛算法优化投影寻踪模型最佳投影方向参数a、利用最小二乘法确定多项式的权系数c、岭函数个数M的群居蜘蛛优化投影寻踪年最大洪峰流量预测模型,结合长江宜昌站(1882年-2004年)的年最大洪峰流量资料进行实例预测,训练阶段平均绝对相对误差为8.61%,预测阶段平均绝对相对误差为10.51%,该模型预测效果较好,模型结果稳定,可有效应用于年最大洪峰流量预测。 相似文献
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Many modeled and observed data are in coarse resolution, which are required to be downscaled. This study develops a probabilistic method to downscale 3-hourly runoff to hourly resolution. Hourly data recorded at the Poldokhtar Stream gauge (Karkheh River basin, Iran) during flood events (2009–2019) are divided into two groups including calibration and validation. Statistical tests including Chi-Square and Kolmogorov–Smirnov test indicate that the Burr distribution is proper distribution functions for rising and falling limbs of the floods’ hydrograph in calibration (2009–2013). A conditional ascending/descending random sampling from the constructed distributions on rising/falling limb is applied to produce hourly runoff. The hourly-downscaled runoff is rescaled based on observation to adjust mean three-hourly data. To evaluate the efficiency of the developed method, statistical measures including root mean square error, Nash–Sutcliffe efficiency, Kolmogorov-Smirnov, and correlation are used to assess the performance of the downscaling method not only in calibration but also in validation (2014–2019). Results show that the hourly downscaled runoff is in close agreement with observations in both calibration and validation periods. In addition, cumulative distribution functions of the downscaled runoff closely follow the observed ones in rising and falling limb in two periods. Although the performance of many statistical downscaling methods decreases in extreme values, the developed model performs well at different quantiles (less and more frequent values). This developed method that can properly downscale other hydroclimatological variables at any time and location is useful to provide high-resolution inputs to drive other models. Furthermore, high-resolution data are required for valid and reliable analysis, risk assessment, and management plans. 相似文献