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991.
In this study, a novel noise reduction algorithm for hyperspectral imagery (HSI) is proposed based on high-order rank-1 tensor decomposition. The hyperspectral data cube is considered as a three-order tensor that is able to jointly treat both the spatial and spectral modes. Subsequently, the rank-1 tensor decomposition (R1TD) algorithm is applied to the tensor data, which takes into account both the spatial and spectral information of the hyperspectral data cube. A noise-reduced hyperspectral image is then obtained by combining the rank-1 tensors using an eigenvalue intensity sorting and reconstruction technique. Compared with the existing noise reduction methods such as the conventional channel-by-channel approaches and the recently developed multidimensional filter, the spatial–spectral adaptive total variation filter, experiments with both synthetic noisy data and real HSI data reveal that the proposed R1TD algorithm significantly improves the HSI data quality in terms of both visual inspection and image quality indices. The subsequent image classification results further validate the effectiveness of the proposed HSI noise reduction algorithm. 相似文献
992.
阐述了一些施工测量高新技术在三峡工程各个施工阶段及各施工部位的应用情况,重点介绍了GPS、测量机器人、数字水准仪、数字摄影测量、激光天顶仪等技术的特点及取得效果. 相似文献
993.
Chen Junyong 《地球空间信息科学学报》2013,16(4):1-4
Urban geo-environment mainly concerns those regards in and around a city, such as the movement of earth crust and earth surface, conditions of hydrology, geology, geography and meteorology. The relevant studies on geo-disaster reduction and the influences resulted from human activities on the geo-environment are included as well. It is stressed in the paper that geo-environmental protection and management are of significance to the sustainable development for Chinese cities. 相似文献
994.
某中小学教学楼为典型的80年代建造的砌体教学楼,鉴定结果显示基础稳定,上部结构材料强度不足,部分构造设置不合理。在结构抗震加固再设计中,从概念上分析结构加固的合理性;合理地确定地震作用影响系数,对加固前后的结构进行整体计算分析;对重要及复杂的部分节点进行补充设计。 相似文献
995.
从项目管理角度出发,介绍关键路径法在项目管理中应用的基本原则和方法,并在《地震监测设施建设标准定额体系研究》项目管理中实际应用,不仅在计划制定期间求得工期、资源、成本的优化,而且在计划的执行过程中,通过信息反馈,进行有效的监督、控制和调整,保证项目在预定期望中的目标实现,通过识别并严格执行关键路径,提高项目管理的效率,压缩项目实施进度. 相似文献
996.
Simon Prikler Hans‐Jürgen Garvens Michael Winterstein Jürgen W. Einax 《洁净——土壤、空气、水》2013,41(8):816-819
Uncertainty assessment of the parameters used for the reporting in the emissions trading system (ETS) to characterize fuels includes not only the processes in a laboratory but has to be expanded for inclusion of sampling and sample preparation. Analysis of variance was used to allocate the contributing uncertainties to the steps described. Apart from some specific results for sampling methods, it was observed that the uncertainty of sampling was in the same order of magnitude than the analytical and the sample preparation error. Several measures to enhance quality assurance in sampling and sample preparation could be derived from specific results. The results were used in the European Monitoring and Reporting Regulation, which set out the requirements for ETS. Sampling and sample preparation have to be included in uncertainty assessment as well as sampling procedures and sampling plans (including quality assurance) have to be agreed upon by the laboratories, carrying out the analytics of those samples. 相似文献
997.
《The Professional geographer》2013,65(1):117-125
This study develops observed climate-based downscaling transfer functions that are used with general circulation model (GCM) output to assess potential global-change impacts on Upper Colorado Plateau, USA, water resources. Daily automated snow water equivalent stations are used with 700 mb atmospheric circulation to determine empirical transfer functions. Downscaling methodologies using multiple regression and neural networks are evaluated, with the neural network results explaining approximately 70%of the daily snowfall variance. The neural network-based transfer functions are used with the GENESIS GCM to simulate snowfall characteristics in both a 1xCO2 and a 2xCO2 climate. While the total precipitation simulated by the 2xCO2 analysis remains nearly the same as today, less will fall as snow; specifically, snow water equivalence shows significant reduction (except in the Green River Basin) as the snow season is reduced by 58 days on average. 相似文献
998.
采用液相还原法制备纳米铁粒子,粒径约为50 nm,主要成分为ɑ-Fe。实验研究了纳米铁还原高浓度硝基苯的效果及反应动力学。结果表明:自制的纳米铁具有很高的活性,短时间内能将高浓度硝基苯彻底还原,效果远优于普通铁粉。当摩尔比满足n纳米铁∶n硝基苯=4∶1时,纳米铁还原硝基苯属于一级反应动力学,反应速率常数和半衰期分别为0.159 3 h-1和4.351 2 h。整个实验过程中,ρ(DO)在0.5 mg/L以下,pH值约为9.0,体系呈弱碱性的厌氧环境,有利于厌氧微生物的生长。纳米铁反应后的产物为Fe6(OH)12CO3和MgFe3O4,且以Fe6(OH)12CO3为主。纳米铁反应后较以前比粒径变化不大,分散性较好,但表面被严重腐蚀。 相似文献
999.
基于地质灾害的多样性及其变化的随机性和非稳定性特点,本文综合利用数学算法和GIS技术,设计了地质灾害预警模型,分析了诱发地质灾害的地形、地貌、气象、水文等几方面的因素,应用地质灾害显式统计预警的基本原理,并通过确定性系数模型(CF)综合分析了天津市地质灾害分布与地质环境基础因素的关系,更好的修订了我市地质灾害预警预报模型.实践证明,应用基于GIS 的地质灾害预警预报系统已在我市近几年的地质灾害气象预警预报中不断完善,预警预报精度得到提高,防灾减灾效果明显,对保护人民生命财产安全发挥了重要作用. 相似文献
1000.