检索结果-南通市图书馆

利用parasol数据反演陆地气溶胶光学厚度

在线全文

学校读者我要写书评

暂无评论

遥感信息 2009年第6期31卷 49-54页

作者：王中挺陈良富李莘莘环境保护部卫星环境应用中心北京100029 遥感科学国家重点实验室中国科学院遥感应用研究所北京100101

研究了利用parasol多角度偏振数据反演我国陆地气溶胶,假设单次散射在扣除大气分子和地表的偏振辐亮度后,根据气溶胶光学性质查找表,采用最佳匹配的方法,选择最适合的气溶胶模式,得到气溶胶光学厚度。并用AERONET的北京站和香河站的地... 详细信息

研究了利用parasol多角度偏振数据反演我国陆地气溶胶,假设单次散射在扣除大气分子和地表的偏振辐亮度后,根据气溶胶光学性质查找表,采用最佳匹配的方法,选择最适合的气溶胶模式,得到气溶胶光学厚度。并用AERONET的北京站和香河站的地基观测数据对结果进行了验证。结果表明,多角度偏振方法反演陆地气溶胶精度稳定,受季节和地表类型的影响很小,但精度较低还需作进一步的改进。

关键词：陆地气溶胶多角度偏振 parasol

在线全文

学校读者我要写书评

暂无评论

太阳伞(parasol)智能充电站

动感（生态城市与绿色建筑） 2016年第3期 12-页

法国标致旗下的设计工作室(Peugeot Design Lab)公布了他们对未来汽车充电站的新设想,外观采用了漂亮的阳伞形设计。这个名为太阳伞(parasol)的电动汽车充电站主体为木质框架,顶端设计了巨大金属面板,可以把收集的太阳能能源转化为电力... 详细信息

法国标致旗下的设计工作室(Peugeot Design Lab)公布了他们对未来汽车充电站的新设想,外观采用了漂亮的阳伞形设计。这个名为太阳伞(parasol)的电动汽车充电站主体为木质框架,顶端设计了巨大金属面板,可以把收集的太阳能能源转化为电力能源,在为充电车辆提供由太阳能产生的电力之余,还可提供遮风挡雨之处。

关键词：太阳伞设计工作室汽车电动汽车充电站 parasol 智能充电站

Uncertainty analysis of hydrological modeling in a tropicalarea using different algorithms

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2018年第4期12卷 661-671页

作者： Ammar RAFIEI EMAM Martin KAPPAS Steven FASSNACHT Nguyen Hoang Khanh LINH Department of Cartography GIS and Remote SensingUniversity of Goettingen37077GoettingenGermany Colorado State University Fort CollinsCO 80523-1476USA Faculty of Land Resources and Agricultural Environment (FLRAE) Flue University of Agriculture and Forestry (F1UAF)Hue UniversityHue City 0084Vietnam

Hydrological modeling outputs are subject to uncertainty resulting from different sources of errors (e.g., error in input data, model structure, and model parameters), making quantification of uncertainty in hydrological modeling imperative and meant to improve reliability of modeling results. The uncertainty analysis must solve difficulties in calibration of hydrological models, which further increase in areas with data scarcity. The purpose of this study is to apply four uncertainty analysis algorithms to a semi-distributed hydrological model, quantifying different source of uncertainties (especially parameter uncertainty) and evaluate their performance. In this study, the Soil and Water Assessment Tools (SWAT) eco-hydrological model was implemented for the watershed in the center of Vietnam. The sensitivity of parameters was analyzed, and the model was calibrated. The uncertainty analysis for the hydrological model was conducted based on four algorithms: Generalized Likelihood Uncertainty Estimation (GLUE), Sequential Uncertainty Fitting (SUFI), Parameter Solution method (parasol) and Particle Swarm Optimization (PSO). The performance of the algorithms was compared using P-factor and Rfactor, coefficient of determination (R (2)), the Nash Sutcliffe coefficient of efficiency (NSE) and Percent Bias (PBIAS). The results showed the high performance of SUFI and PSO with P-factor > 0.83, R-factor 0.91, NSE > 0.89, and 0.18 < PBIAS < 0.32. Hence, we would suggest to use SUFI-2 initially to set the parameter ranges, and further use PSO for final analysis. Indeed, the uncertainty analysis must be accounted when the outcomes of the model use for policy or management decisions.

关键词： SWAT-CUP GLUE SUFI2 parasol PSO Vietnam

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

近红外偏振辐射卫星数据的海洋耀光动态检测

遥感学报 2019年第2期23卷 215-229页

作者：陈震霆孙晓兵汪俊锋李树黄红莲陈卫乔延利中国科学院合肥物质科学研究院通用光学定标与表征技术重点实验室合肥230031 中国科学技术大学合肥230026 昆明学院信息技术学院昆明650214 电子工程学院合肥230037

太阳光入射海表特定区域形成海洋耀光,呈强反射和偏振特性。在卫星海洋遥感中,海洋耀光对遥感成像质量有较大影响,尤其对海洋上空云、气溶胶及海色等研究干扰较大,因此剔除海洋耀光是卫星遥感数据处理过程中首先要解决的重要问题。以PAR... 详细信息

太阳光入射海表特定区域形成海洋耀光,呈强反射和偏振特性。在卫星海洋遥感中,海洋耀光对遥感成像质量有较大影响,尤其对海洋上空云、气溶胶及海色等研究干扰较大,因此剔除海洋耀光是卫星遥感数据处理过程中首先要解决的重要问题。以parasol卫星的POLDER3载荷数据为研究对象,获取载荷成像时刻太阳及观测几何、海表风速风向及气溶胶光学厚度等参数,采用海气辐射传输相关理论,结合耀光角和多角度NIR偏振辐射信息(865 nm),构建基于近红外偏振辐射特性规则的OGDD模型,获取耀光角临界值实现耀光动态检测。以印度洋某海区为研究对象,获取实测耀光区NIR通道的大气层顶反射率和偏振反射率,利用OGDD模型将耀光角判别临界值调整为34°。相比MODIS经验临界值(40°),标记耀光像元相对减少了30%。结果表明,该方法不仅能通过动态调整临界值准确识别海洋耀光,为云检测及云物理特性反演提供可靠的源数据,还能为高分五号卫星多角度偏振载荷在轨定标及气溶胶反演提供支持。

关键词： parasol 海气辐射海洋耀光辐射信息偏振反射率动态检测高分五号偏振遥感

A Comparison of SWAT Model Calibration Techniques for Hydrological Modeling in the Ganga River Watershed

在线全文

学校读者我要写书评

暂无评论

Engineering 2018年第5期4卷 643-652页

作者： Nikita Shivhare Prabhat Kumar Singh Dikshir Shyam Bihari Dwivedi Indian Institute of Technology Banaras Hindu University Varanasi 221005 India

The Ganga River, the longest river in India, is stressed by extreme anthropogenic activity and climate change, particularly in the Varanasi region. Anticipated climate changes and an expanding populace are expected to further impede the efficient use of water. In this study, hydrological modeling was applied to Soil and Water Assessment Tool （SWAT） modeling in the Ganga catchment, over a region of 15 621.612 km2 in the southern part of Uttar Pradesh. The primary goals of this study are： ① To test the execution and applicability of the SWAT model in anticipating runoff and sediment yield; and ② to compare and determine the best calibration algorithm among three popular algorithms-sequential uncertainty fitting version 2 （SUFI-2）, the generalized likelihood uncertainty estimation （GLUE）, and par-allel solution （parasol）. The input data used in the SWAT were the Shuttle Radar Topography Mission （SRTM） digital elevation model （DEM）, Landsat-8 satellite imagery, soil data, and daily meteorological data. The watershed of the study area was delineated into 46 sub-watersheds, and a land use/land cover （LULC） map and soil map were used to create hydrological response units （HRUs）. Models utilizing SUFI- 2, GLUE, and parasol methods were constructed, and these algorithms were compared based on five cat-egories： their objective functions, the concepts used, their performances, the values of P-factors, and the values of R-factors. As a result, it was observed that SUFI-2 is a better performer than the other two algo-rithms for use in calibrating Indian watersheds, as this method requires fewer runs for a computational model and yields the best results among the three algorithms. parasol is the worst performer among the three algorithms. After calibrating using SUFI-2, five parameters including the effective channel hydraulic conductivity （CH_K2）, the universal soil-loss equation （USLE） support parameter （USLE_P）, Manning＇s n value for the main channel （CH_N2）, the surface runof

关键词： Remote sensing Geographic information system Soil and Water Assessment Tool Hydrological modeling SUFI-2 GLUE parasol Sediment yield

Runoff and Sediment Modeling Using SWAT in Gumera Catchment, Ethiopia

在线全文

学校读者我要写书评

暂无评论

Open Journal of Modern Hydrology 2013年第4期3卷 196-205页

作者： Kaleab Habte Michael Mamo Manoj K. Jain Department of Hydrology Indian Institute of Technology Roorkee India.

This study was undertaken to examine the applicability of the SWAT model in Gumera river basin upstream of Lake Tana, Ethiopia for simulating stream runoff and sediment load. The area of river basin was discretized into 24 sub-catchments using ArcSWAT interface of the model. The semi automated Sequential Uncertainty Fitting (SUFI2) and fully automated Parameter Solution (parasol) calibration process built in SWAT calibration and uncertainty program (SWAT-CUP) were used to calibrate the model parameters using time series of flow and sediment load data of 1994 to 2002 and validated with the observed data from years 2003 to 2006. The performance of the model was evaluated using statistical and graphical methods to assess the capability of the model in simulating the runoff and sediment yield for the study area. The coefficient of determination (R2) and NSE values for the daily runoff by using [parasol] optimization technique was obtained as 0.72 and 0.71 respectively for the calibration period and 0.79 and 0.78 respectively for the validation period, R2 and NSE values of monthly flow calibration using SUFI2 are 0.83 and 0.78 respectively for validation it was 0.93 and 0.93. For monthly sediment yield by using SUFI2 calibration technique the model evaluation coefficients R2 and NS for calibration was computed as 0.61 and 0.60 respectively, for validation it was 0.84 and 0.83 respectively. The sensitivity analysis on 13 runoff producing parameters was also carried out and discussed.

关键词： Calibration Validation Runoff Sediment Yield SWAT-CUP SUFI2 parasol

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

海面溢油耀光偏振遥感实验研究

海面溢油耀光偏振遥感实验研究

作者：周杨南京大学

学位级别：硕士

溢油污染会给海洋生态环境和人类社会经济发展造成巨大危害。基于海面溢油污染的风化迁移过程,结合目视特征和光学作用过程,溢油污染的光学遥感监测目标主要为:黑色浮油、不同厚度的油膜和溢油乳化物。微波雷达遥感、光学遥感、热红外... 详细信息

溢油污染会给海洋生态环境和人类社会经济发展造成巨大危害。基于海面溢油污染的风化迁移过程,结合目视特征和光学作用过程,溢油污染的光学遥感监测目标主要为:黑色浮油、不同厚度的油膜和溢油乳化物。微波雷达遥感、光学遥感、热红外遥感、紫外遥感和激光诱导荧光等技术可应用于海面溢油监测,具有各自不同的特点。光学偏振遥感作为一种新型遥感技术,被用于气溶胶、云、水体等目标的探测、识别与定量反演,也能为海面溢油污染监测提供新的思路和解决方案。偏振能增强海面溢油与背景海水的反射差异,但在溢油光学偏振探测机理、模型构建、卫星偏振遥感探测应用与分析等方面尚缺乏系统性研究。耀光是海面对直射太阳光的镜面反射,溢油表面和海面会产生显著的反射耀光偏振差异,这种较强的反射偏振信号也蕴含了溢油和海水的物理属性差异。本文基于海洋溢油光学偏振遥感探测机理,构建海面溢油耀光偏振模型,设计开展室内模拟实验进行验证;进一步选取典型溢油事故的多角度光学偏振遥感影像,开展海面溢油多角度反射耀光的偏振遥感探测应用与分析。主要研究内容包括:(1)基于偏振光学理论、Cox-Munk模型和菲涅尔反射理论等构建海面溢油耀光偏振模型。模拟不同观测几何(太阳天顶角、探测器天顶角和相对方位角)、不同折射率溢油与海水表面耀光的偏振度差异,分析溢油光学偏振探测最优角度。针对光学遥感中的“临界角”,模拟对应观测几何下溢油与海水表面耀光偏振特性差异,评估偏振遥感在临界角区域内溢油探测效能。(2)针对模型推导结论,设计开展室内多角度CCD偏振成像模拟实验,以全波段钨灯加窄带滤光片模拟准单色平行非偏入射光(635nm),以面阵CCD为探测设备,获取多观测角度(传感器天顶角等于光源天顶角,二者变化范围是15～55°,角度变化间隔5°)、镜面反射方向上水面与油膜表面不同偏振方向上辐亮度信号,计算斯托克斯矢量(I、Q、U分量)及偏振度。分析水体和油膜表面反射光偏振度随角度变化规律,讨论偏振度差异对观测角度的敏感性,验证理论分析结果。(3)基于典型海上溢油事故,选取法国parasol多角度卫星光学偏振遥感影像,开展海面溢油的多角度光学偏振遥感分析。验证耀光条件和非耀光条件下,模型模拟值与卫星观测值的变化趋势,评估海面耀光偏振模型模拟精度。分析海洋溢油与背景海水多角度下偏振特性差异,阐明耀光条件下偏振遥感对海上溢油的探测效能,评估大气散射对溢油多角度光学偏振遥感探测的影响。基于上述研究内容,得出主要结论如下:(1)基于偏振光学基本原理、Cox-Munk模型和菲涅尔反射理论等构建的海面溢油耀光偏振模型,适用于海面存在耀光条件下的溢油探测;在非耀光条件下,本研究所构建模型尚需进一步改进。(2)溢油耀光偏振度低于背景海水耀光偏振度,且溢油、海水表面耀光偏振度及二者偏振度差异对几何角度变化敏感,当相对方位角为180°,太阳天顶角与传感器天顶角之和为82.6°时,溢油与背景海水偏振度差异最明显,为溢油耀光偏振探测最优角度。(3)parasol多角度、多光谱偏振遥感数据分析表明光学偏振遥感在太阳耀光条件下具备海上溢油探测能力,且耀光越强,探测能力越强。(4)海面溢油耀光偏振模型模拟结果表明,对光学遥感影像中的潜在临界角区域,光学偏振遥感具备探测此处海面溢油的潜力。

关键词：溢油耀光海洋偏振遥感 parasol