Incorporating variable source area hydrology into a curve-number-based watershed model

Many water quality models use some form of the curve number (CN) equation developed by the Soil Conservation Service (SCS; U.S. Depart of Agriculture) to predict storm runoff from watersheds based on an infiltration-excess response to rainfall. However, in humid, well-vegetated areas with shallow soils, such as in the northeastern USA, the predominant runoff generating mechanism is saturation-excess on variable source areas (VSAs). We reconceptualized the SCS–CN equation for VSAs, and incorporated it into the General Watershed Loading Function (GWLF) model. The new version of GWLF, named the Variable Source Loading Function (VSLF) model, simulates the watershed runoff response to rainfall using the standard SCS–CN equation, but spatially distributes the runoff response according to a soil wetness index. We spatially validated VSLF runoff predictions and compared VSLF to GWLF for a subwatershed of the New York City Water Supply System. The spatial distribution of runoff from VSLF is more physically realistic than the estimates from GWLF. This has important consequences for water quality modeling, and for the use of models to evaluate and guide watershed management, because correctly predicting the coincidence of runoff generation and pollutant sources is critical to simulating non-point source (NPS) pollution transported by runoff. Copyright © 2007 John Wiley & Sons, Ltd.     

电厂管线信息管理系统构建

本文以上海外高桥电厂为例，从系统设计的原理和特点出发，构建包括基础地理数据、专业应用数据及监测数据的系统数据体系，建立包括地形图编辑管理模块、管线数据编辑管理模块、可视化三维浏览模块、管线运行监控子系统、事件分析处理模块、GPS-RTK定位子系统等功能模块的电厂管线信息管理系统。     

试论测绘人才资源发展策略

本文通过对测绘人才资源现状的分析 ,从影响测绘生产单位人才资源开发与管理的发展策略的因素出发 ,研究探讨如何选择测绘人才资源开发与管理的发展策略。     

危险率函数在地表破裂型地震危险性评估中的应用—以宁夏灵武断裂为例

在对中国北部板内地区的古地震资料拟合、给出时间相依的统计模型基础上,利用近期获取的灵武断裂有关资料和危险率函数,对灵武断裂未来一定时段的发震潜势和当前地震危险性特征进行了分析,认为该断裂已进入发震时段,在未来10－100年内有发生7．0－7．5级左右地震的潜势。     

气候变化对中国农业生产的影响

根据１９５８￣１９９７年中国３１０个气象站的月平均最高、最低气温,月平均降水量,日照时数等气象参数分析了中国气候的背影特征。用３个大气环流模型,即ＨａｄＣＭ２、ＣＧＣＭ１、ＥＣＨＡＭ４来模拟未来中国气候变化的情景。同时,建立未来气候变化的６种方案。最后,根据３个ＧＣＭｓ模拟的结果,利用国际应用系统分析研究所（ＩＩＡＳＡ）发展并改进的农业生态地带模型（ＡＥＺ）评估气候变化对中国农业生产的影响。评估主     

高频电磁波测井同时求解视电导率和视介电常数

利用 Ｌａｍｂｅｒｔ Ｗ函数的性质,针对单发单收和单发双收两种电磁波测井仪器,给出 了一种求解视介电常数和视电导率的方法．理论分析和数值实验表明,该方法在计算速度和 精度方面,明显优于传统的求解复杂非线性方程组的方法．与查表方法相比,该方法不需要 预先计算大量图版,且精度较高．     

海平面对大气压变化的响应及其对地球自转的影响

介绍了海平面对于大气压变化的响应（反变气压计响应）的理论现状及其今后发展方向,以及反变气压计响应对于地球自转激发函数的影响。有关研究成果表明,反变气压计响应的影响具有时域、频域性,且其随时空的变化比较明显,因此,详细研究其动态特征并应用于地球物理领域的前景广阔。     

Predicting Bathymetry from the Earth's Gravity Gradient Anomalies

Historically, prediction of ocean floor depth, or bathymetry, has been based on the isostatic modeling and linearized relationships between gravity anomalies and bathymetry. The need for isostatic modeling limits the application of the resulting bathymetry predictions as constraints in geophysical models. An alternative technique making use of the Earth's vertical gravity gradient for predicting bathymetry is explored in this paper. This technique is based on the fact that the observed gravity gradient anomalies result primarily from local mass concentrations on the ocean floor, and that mass compensation by the oceanic crust has an insignificant effect on the gravity gradients, and can be neglected. The resulting bathymetry prediction therefore is independent of isostatic modeling assumptions, allowing it to be used as a constraint on models of lithospheric compensation and for other geodetic and geophysical applications.     

城市生态休闲带开发的功能与效应分析

在界定了城市生态休闲带概念的基础上,论述了城市生态休闲带的基本特征,并分别从城市格局、城市空间扩展、生态环境、休闲需求、旅游环境、城市形象以及城市文化等方面分析了城市生态休闲带开发的功能与效应.指出城市生态休闲带的开发既可以发挥其对城市功能体的溶解效应、生态间隔和屏障效应,又能够充分满足城市的休闲需求,同时还能补充和完善城市的旅游环境,对于城市的现代化建设和可持续发展是一个新的思路.     

港珠澳大桥的客流车流量预测与功能定位

概述了港珠澳大桥的7个主要方案及分歧,把产生分歧的原因归结为大桥功能定位的差异.通过对1999～2002年往返香港至珠三角的过境客流和车流数据作定量分析,获得未来往返两地的过境客流和车流趋势预测数据,再结合珠三角以及珠三角各部分的经济发展状况得出港珠澳大桥的客流量和车流量的预测数据.根据港珠澳大桥的客流量和车流量预测结果和区域基础设施协调和发展规划理论,认为大桥的功能定位应为客、货运兼备;宜建设铁路、公路两用桥.