基于神经网络的非线性系统的输出调节

非线性系统输出调节问题可解的充要条件是存在一个中心流形满足某个非线性偏微分方程。本文用多层前向神经网络求解该非线性偏微分方程，从而逼近非线性系统的中心流形。在此基础上，构造状态反馈控制律，实现非线性系统的输出调节。     

Ecological effects of river regulation on mammals and birds: A review

Although most of the world's river systems are regulated, the effects of river regulation on mammals and birds are little known. In fact, speculations are more common than empirical data. A review of this topic is presented, emphasizing northern rivers where most impacts have been described. Effects are related to the major causes of change. It is concluded that the two most disastrous effects of river regulation on mammals and birds are the permanent inundation of vast areas of land, and the disruption of the seasonal flood regime along the river. The design of future investigations to improve our knowledge is considered.     

Effect of a changed temperature regime on the benthos of a norwegian regulated river

The lowermost 20 km of the River Surna, north-western Norway receives cool water during summer from a hypolimnetic release mountain reservoir. The benthic fauna is completely dominated by insects. Benthic densities immediately below the power station are much lower than at all other localities. Although benthic densities increase downstream of the power station, they never exceed the densities above. The dominant insect group, chironomids, can be divided into four categories according to their abundance and distribution above and below the power station: (1) rare or absent above, but common or abundant below; (2) abundant or common above but rare or absent below; (3) slightly less abundant below; (4) unchanged abundance. No major differences in the species composition were recorded for stonefilies, mayflies and caddisflies.     

大坝安全管理的重要意义──四川省部属水电站大坝首轮定检的主要经验

本文简述了美英等国及我国在坝工安全管理法制建设的历史，说明大坝安全管理的重要性．回顾我局大坝安全监控中心成立以来，对局属水电厂大坝安全管理走上正规化、规范化、制度化所进行的工作；总结局属水电厂大坝安全首轮定检的过程与主要经验并对今后工作提出建议．     

黄河水资源矛盾及其出路探讨

针对黄河水资源日前紧张的状况，分析了龙羊峡和刘家峡水库蓄水黄河下游的影响，提出了解决缺水问题的几条出路：（１）黄河上游水库群应从整体利益出发，尽可能满足水资源综合利用的要求，龙羊峡水库远在上游，其运行应重点考虑发电，而刘家峡水库应减少冬季泄量，更多地考虑宁蒙河段防凌，灌溉和防洪要求；（２）应促使大柳树反调节水库尽快兴建；（３）小浪底水库建成后，应以保证下游防洪，供水和减淤为主，而三门峡水库则应以加     

对南水北调中线工程向河南省供水的看法

南水北调中线河南供水区是河南省经济条件较好，发展较快的地区，但水资源紧缺成为该区经济发展的主要制约因素，中线工程近期方案河南３５年平均引汉水５２．９亿ｍ＾３，但来水和用水过程不完全匹配，须采用引汉和当地水资源联合运用，才能使水资源得到充分利用，经过２０００年供需平衡分析比较，认为中线工程的实施，对缓解河南省水资源紧缺状况，促进河南经济发展具有重要战略意义，是解决河南缺水不可替代的工程措施。     

东江水库调节对其下游各级水库淹没的影响

河流梯级开发中，上游有龙头水库时，对下游调节作用较大。如湖南省东江水库系一大型多年调节水库，调节系数为１．３。考虑利用该库空闲库容容纳洪水，减少下泄流量，与区间洪水组合后，下游各梯级设计洪水在洪水标准低于３０年一遇时，其值比原设计小，相应回水降低，淹没损失减少，以东江下游乔口－遥田７个梯级为例，其中乔口，石面担，程江口，永兴，上堡等５梯级减少的淹没损失是原各梯级淹没损失的７８．７２％，经济效益显著     

Regulating the River Severn

The River Severn is the longest of Britain's regulated rivers: this chapter describes the geography of the river's catchment area, from its source in central Wales to the Bristol Channel where it flows into the sea. It then considers the historical development of the Severn as a water resource, culminating in the construction of Llyn Clywedog and more recently the Shropshire Groundwater Scheme to augment low river flows and support greatly increased abstractions. Plans for even more substantial development of the resource system appropriate to the rapid demand growth of the 1960s and early 1970s are discussed. Practical experience in regulating flows in the river gained during the drought of 1976 is described and used to explain recent developments in the practice and monitoring of river regulation.     

单纯用动力制动下放位能负载及其调速

矿井单滚筒提升绞车或双滚筒用做单钩提升下放重物时，原TKD电控系统不能满足其要求。为此．利用动力制动直接下放位能负载使其控制更加趋于合理，保护得到很好的利用。