长江口洪季水动力对海平面上升的响应特征

考虑到海平面上升对长江口水动力构成的严重威胁,该文基于MIKE21软件建立了长江口二维水动力数学模型,采用实测潮位、流速以及流向资料对模型进行了验证。对相关文献和IPCC报告进行总结归纳,得到2100年海平面保守上升值约为0.5 m。运用验证好的数学模型对海平面上升0.5 m后长江口洪季水动力进行了数值模拟。计算结果表明:海平面上升后,涨潮时间增长,落潮时间缩短;海平面上升0.5 m后,长江口南北支、南北港以及南北槽高潮位增加了0.43 m–0.46 m,高潮位增幅沿程向上减小,北支上段涨潮动力受阻较明显(潮位增幅较大);海平面上升0.5 m后,北支流速增幅比南支大,北支上段落潮流量增幅达82.8%,对北支水道的发展有利。总体而言,海平面上升对目前长江口沿岸的标准构成了一定威胁,但对已经衰退的北支水道有利。     

雁栖河流域水质的关键影响因素研究

针对雁栖河流域水质变差、富营养化风险增加等问题,通过对流域水质的连续监测,确定了影响流域水质的控制指标是TN和TP.在水质监测的基础上分析了流域水质的时空分布规律,并对流域污染负荷进行了调查和估算,在此基础上采用MIKE21建立平面二维水动力水质模型,对雁栖湖水质变化规律进行了模拟.研究表明,影响流域水质的关键因素是渔...     

MIKE21模型在南新联圩洪水模拟中的应用

为了分析江西省南新联圩防洪保护区在圩提溃决后洪水在区内的演进过程,根据南新联圩防洪保护区周围湖泊、河流及圩区情况,建立了模拟保护区内洪水演进的MIKE21模型。分别采用2010年和2012年实测洪水资料对模型进行率定和验证,结果表明模型具有较高的模拟精度。在赣江50 a一遇洪水叠加湖口22.5 m洪水位(1954年型)的工况下,利用所建立的模型对防洪保护区内的淹没水深、流速和洪水演进过程等进行计算分析,获得了南新联圩防洪保护区发生溃堤后的受灾发展情况。研究成果可为南新联圩防洪预警及时发布、转移财产、逃生避险等提供技术支撑。     

ITU-T误码性能建议之二

对于用于传送广播电视节目的国家和城域干线网，误码性能是一个关键的传输性能指标。本文介绍了ITU—T的几个主要的误码性能建议，希望能对干线网传输系统的建设和维护有所帮助。     

浅谈面向21世纪的电力电子技术

探讨了21世纪中电力电子技术的研究课题，该课题有的是现有电力电子技术的深化，有的则是新开辟的研究领域。     

国际上数字影院技术标准进展综述

本文重点介绍了国际上制定数字影院标准的主要组织及截止到2008年已发布的备类标准的内容;分析了制定轨迹、框架及相互关系;并对一些新领域的数字电影标准研究工作做了展望.     

A Bayesian spatial econometric analysis of the 2010 UK General Election

The Conservative Party won the 2010 General Election in the United Kingdom, gaining the most votes and seats of any single party. Using Bayesian spatial econometric methods, we show that significant spatial dependence exists in Conservative voting behaviour and select the spatial Durbin model as the best model to explain this phenomenon. This paper examines these spatial effects as well as the effects of a range of economic, socio‐economic, and political variables. Perhaps the most interesting result is that incumbency has effects beyond an incumbent's own constituency.     

Sharing Rivers for Peace,Development, and Security

Abstract

Water is a finite resource, and with the considerable upsurge in population, urbanization, and industrialization, it is also becoming an increasingly scarce resource. Many countries in the world rely on river waters, and many of those rivers are shared by two or more countries. Dams on those rivers have been a major source of tensions, disputes, and, in some cases, even conflict between riparian countries because dams could result in massive diversion of river flows. Those developments have, inter alia, highlighted the relevance and importance of the principles of international water law, as reflected in the United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses. The World Commission on Dams has also underscored the importance of, and elaborated on, those principles with regard to dams on shared rivers. This article discusses and analyzes the recommendations of the Commission in this area, and compares them with the principles of international water law as enunciated in the United Nations Convention