察尔汗盐湖资源与我国钾肥工业发展

概述了察尔汗盐湖的自然条件、地质条件与资源状况,阐明了我国钾肥工业的现状以及察尔汗盐湖资源开发对发展我国钾肥工业的重要作用。     

A heuristic approach for packing identical rectangles in convex regions

In this paper we propose a heuristic approach for the problem of packing equal rectangles within a convex region. The approach is based on an Iterated Local Search scheme, in which the key step is the perturbation move. Different perturbation moves, both combinatorial and continuous ones, are proposed and compared through extensive computational experiments on a set of test instances. The overall results are quite encouraging.     

利用ETM数据进行矿化蚀变信息提取的方法研究——以柴北缘地区为例

在柴北缘地区利用ETM数据进行遥感矿化蚀变信息提取方法研究主要基于三个方面：①研究区蚀变信息及背景干扰地物信息的光谱特征;②矿化蚀变信息提取的最佳变量集组合;③图像增强处理方法和流程。在综合分析研究的基础上,采用“图像掩膜→最佳变量组合→波段比值→主成分分析→阈值分割→多元数据综合分析及异常筛选”的方法和流程提取了柴北缘成矿带的矿化蚀变异常信息,为该区综合成矿预测提供了可靠依据。     

无线传感器网络山洪监测数据汇聚平台

针对山洪形成原因的复杂性和不确定性,本文通过BP神经网络对历史数据进行整理,提出了基于多传感器信息融合的数据汇聚平台的设计。此平台可以实现实时汇聚小流域水位、降雨量等监测数据,对汇聚数据进行数据解析、信息融合,通过GPRS将采集的数据发送到远程后台数据中心。本文在硬件上设计完成了基于S3C2440的数据汇聚平台;在软件上完成了节点的控制、山洪监测数据显示、预警临界值设定及山洪预警功能的设计。通过实验表明,山洪监测系统利用此设计平台进行安全评价是有效的、可靠的。     

黑河下游河道渗漏面积的估算及其精度初步研究

黑河流域是我国西北干旱区内陆河的一个典型流域,其下游生态环境用水主要来源于地下水,地下水的补给主要通过河流的渗漏过程,因此河道渗漏补给是下游生态用水的主要来源。定量确定河道渗漏水量之前,首先需要确定河道渗漏面积。由于野外条件的限制,河道过水过程中黑河下游狼心山至东居延海区间河道的渗漏面积实地测量非常困难。根据水文流量资料选取2001年、2002年、2004年、2009年四年中全断面过水ETM遥感影像数据,在此基础上,运用遥感与GIS技术研究了对应时间黑河下游河道渗漏面积。选取具有不同特征的五段河道,运用AutoCAD软件对遥感提取结果进行误差分析,得到平均相对误差为4.29%,证明直接利用监督分类方法提取得到的结果具有较高的精度。在此基础上,建立渗漏面积与河长之间的关系。为该区域的水文过程及河道周围生态环境等的研究提供了数据和研究基础。     

SODA: A new method of in-scene atmospheric water vapor estimation and post-flight spectral recalibration for hyperspectral sensors: Application to the HyMap sensor at two locations

A new method of estimating per-pixel atmospheric column water vapor (ACWV) and potential differences in the reported band center wavelengths of the HyMap sensor has been developed. The new method uses variations of a second order derivative algorithm (SODA) to assess the impact of atmospheric residual features on calculated surface reflectance spectra after atmospheric compensation. The SODA method provides an alternative to the current band ratio techniques of ACWV estimation and also allows the same form of algorithm to be used for the estimation of possible band shifts. A comparison of in-situ measured surface reflectance at two field sites in Western Australia demonstrates improvement in the resulting spectra when post-flight updates are made to the reported HyMap band center wavelengths and applied during the atmospheric compensation process. The same SODA methodology was varied to estimate the ACWV on a per-pixel basis and found to significantly reduce the appearance of the underlying surface structure on the resulting ACWV images as well as improve the overall accuracy of the estimation. The ACWV estimated from the HyMap imagery at the two field sites was found to agree with in-situ atmospheric ACWV measurements to within 2% and represented a two fold increase in accuracy over a 3 band ratio Continuum Interpolated Band Ratio (CIBR) technique of ACWV estimation.     

Water property monitoring and assessment for China's inland Lake Taihu from MODIS-Aqua measurements

We provide results of quantitative measurements and characterization for inland freshwater Lake Taihu from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the satellite Aqua. China's Lake Taihu, which is located in the Yangtze River delta in one of the world's most urbanized and heavily populated areas, contains consistently highly turbid waters in addition to frequent large seasonal algae blooms in various lake regions. Thus, satellite data processing requires use of the shortwave infrared (SWIR) atmospheric correction algorithm. Specifically for Lake Taihu, an iterative SWIR-based atmospheric correction algorithm has been developed and proven to provide reasonably accurate water-leaving radiance spectra data. Using MODIS-Aqua measurements, the blue-green algae bloom in Lake Taihu in 2007 has been studied in detail, demonstrating the importance and usefulness of satellite water color remote sensing for effectively monitoring and managing a bloom event.Seasonal and interannual variability, as well as spatial distributions, of lake water properties were studied and assessed using the MODIS-Aqua measurements from 2002 to 2008. Results show that overall waters in Lake Taihu are consistently highly turbid all year round, with the winter and summer as the most and least turbid seasons in the lake, respectively. Extremely turbid waters in the winter are primarily attributed to strong winter winds that lead to significant amounts of total suspended sediment (TSS) in the water column. In addition, MODIS-Aqua-measured water-leaving radiance at the blue band is consistently low in various bay regions in Lake Taihu, indicating high algae concentration in these regions. Climatological water property maps, including normalized water-leaving radiance spectra nL_w(λ), chlorophyll-a concentration, and water diffuse attenuation coefficient at the wavelength of 490 nm (K_d(490)), are derived from all MODIS-Aqua data from 2002 to 2008 for Lake Taihu, showing overall spatial distribution features for the lake water property.     

基于约束区域的BSB联想记忆模型

提出一种根据联想记忆点设计基于约束区域的ＢＳＢ（Ｂｒａｉｎ－Ｓｔａｔｅ－ｉｎｍ－ａ－Ｂｏｘ）神经网络模型,它保证了渐近稳定的平衡点集与样本点集相同,不渐近稳定的平衡点恰为实际的拒识状态,并且吸引域分布合理,从而将ＥＳＢ完善为理想的联想记忆器。     

新疆玛纳斯河流域水资源利用与管理

随着社会经济发展,生活水平的提高以及城市规模的扩大,玛纳斯河流域内水资源供需矛盾日益突出,用水结构发生重大变化,水资源污染日趋恶化。探讨流域水资源在利用与管理过程中出现的诸多问题,并提出改进的几点意见与建议。     

变动态存储系数法在辽宁大凌河流域河道洪水演算中的运用研究

本文选用变动态存储系数法进行河道洪水演算,弥补传统水文模型河道洪水演算将洪水传播时间设为定值的不足。论文选取辽宁大凌河上游大城子水文站2000-2013年15场洪水资料对模型进行率定和验证,并和传统水文模型河道洪水演算方法模拟结果进行对比研究,结果表明相比于传统水文模型,采用变动态存储系数法的洪水模拟精度有所提高,15场洪水模拟合格率提高20%。研究成果对于大凌河流域水文模拟,特别是分布式水文模拟提供较为重要的参考价值。