Digital Yellow River Model

Soil erosion is one of the key concerns in land use management for the Loess Plateau of the Yellow River, where serious soil loss is the root cause of environmental and ecological degradation of the basin. In this paper, a physically-based, distributed-parameter, and continuous erosion prediction model at the river basin scale was developed with the aim of assisting in developing better land use management strategies. The framework, the major supporting techniques, and the typical erosion processes are described. The physical processes of sediment yield and transport in the Loess Plateau are divided into three sub-processes, including the runoff and sediment yield on hillslopes, gravitational erosion in gullies, and hyperconcentrated flow routing in channels. For each sub-process, a physically-based simulation model was developed and embedded into the whole model system. The model system was applied to simulate the runoff and sediment yield in several typical years in the coarse sediment source area of the Loess Plateau, and the simulated results were in reasonably good agreement with the measured values.     

论黄河三角洲流路演变及河口治理的指导原则

通过分析黄河三角洲流路演变中溯源堆积及溯源冲刷对典河下游河道影响的范围，幅度和作用历时，提出在黄河泥沙从根本上减少之前，河口治理的指导原则应是在有利于工农业发展和有利于防洪防凌前提下，有计划地安排河口流路。     

印制板蚀刻、微蚀刻废液的再生和铜回收的技术及设备

传统的印制板蚀刻废液处理方法存在着工艺落后、操作不便、二次污染、效益不高等问题,本工艺采用特殊的萃取电解、吸附电解技术,使蚀刻废液得以再生循环利用,铜得以100%回收,低含铜废水铜得到98%回收,整个系统不产生二次污染,获得的铜为高纯度铜板,在实现污染控制的同时,废液废水得到了资源化利用。     

大通河调水对水资源及生态环境的影响

基于生态需水、河流纳污能力、水环境容量等理论,分析研究大通河调水前后可能引起的河道生态环境各要素变化的程度和范围。结果表明,跨流域调水将引起不同河段水资源的剧烈变化,特别是天堂寺、享堂河段会产生断流,进而对河道内生态、水环境及河谷周边陆地生态产生显著影响。综合各方面需水要求,下泄月平均流量至少不小于1.1 m3/s。     

乌江流域大型复杂水电站群联合优化调控关键技术及其应用研究

根据乌江流域总体规划、长江三峡以上防洪要求、南方电网运行特点、乌江流域水文特性等,贵州乌江水电开发有限责任公司组织开展了乌江梯级水库优化调度和发电优化控制的基本理论研究,并根据该研究建立了乌江流域水电站群联合优化调控系统,经过一系列优化调度规则、方法、措施在系统中的应用,实现了节水增发电的目的,取得了良好的社会经济效益。     

广西河道管理和保护范围确权划界探讨

分析了广西河道管理范围和保护范围确权划界工作存在的问题,总结了广西近年来河道管理范围和保护范围确权划界的做法和经验,提出了下一步促进河道管理范围和保护范围确权划界工作的思路.     

Salmonid observations at a Klamath River thermal refuge under various hydrological and meteorological conditions

The Beaver Creek confluence with the main‐stem Klamath River was studied to assess salmonid use in a thermal mixing zone under various summer hydrological and meteorological conditions. Main‐stem flow releases from Iron Gate Dam ranged from 17 cms (615 cfs) to 37 cms (1320 cfs) during the study period and main‐stem water temperatures ranged from 19.5 to 26°C. A grid was constructed to define the thermal refuge as a system of cells. Temperatures were monitored using remote temperature loggers and fish counts were conducted using daytime snorkelling. Most juvenile salmonids were observed moving into the refuge when main‐stem temperatures exceeded 22–23°C. Salmonids in the thermal refuge did not necessarily seek the coolest water, but were generally located in habitats commensurate with species‐specific behavioural needs within their thermal tolerance range. Such ranges largely occurred within refuge areas. Variable meteorological conditions confounded observable biological thermal benefit to fish resulting from higher or lower main‐stem flows. Thermal regime dynamics indicated that under the hydrological and meteorological conditions observed, higher flows from Iron Gate Dam showed some ability to change the structure of the refuge area. It appeared that without the thermal refuge, main‐stem flows alone could not sustain the salmonid population because high water temperatures usually exceeded their published thermal tolerance limits. Copyright © 2007 John Wiley & Sons, Ltd.     

脉冲噪声环境下宽带循环平稳信号DOA估计算法

针对传统二阶循环相关算法在脉冲噪声环境中的显著退化问题,本文以α稳定分布为噪声模型,提出基于分数低阶循环相关的波达方向(Direction of arrival,DOA)估计算法。利用分数低阶循环相关的相移特性,将宽带循环平稳信号的DOA估计问题转化为"中心频率"为ε的窄带问题,解决了宽带情况下DOA估计困难的问题。计算机仿真结果进一步验证了此算法的有效性,且性能优于传统SC-SSF(Spectral correlation signal subspacefitting)算法。