A web-based land surface remote sensing products validation system (LAPVAS): application to albedo product     

Xingwen Lin  Yong Tang  Mingguo Ma  Dongqin You  Baocheng Dou 《International Journal of Digital Earth》2018,11(3):308-328

Quantitative remote sensing product (QRSP) validation is a complex process to assess the accuracy and uncertainty independently using reference data with multiple land cover types and long-time series. A web-based system named as LAnd surface remote sensing Product VAlidation system (LAPVAS) is described in this paper, which is used to implement the QRSPs validation process automatically. The LAPAVS has two subsystems, the Validation Databases Subsystem and the Accuracy Evaluation Subsystem. Three functions have been implemented by the two subsystems for a comprehensive QRSP validation: (1) a standardized processing of reference data and storage of these data in validation databases; (2) a consistent and comprehensive validation procedure to assess the QRSPs’ accuracy and uncertainty; and (3) a visual process customization tool with which the users can register new validation data, host new reference data, and readjust the validation workflows for the QRSP accuracy assessment. In LAPVAS, more than 100 GB of reference data warehoused in validation databases for 13 types of QRSPs’ validation. One of the key QRSPs, land surface albedo, is selected as an example to illustrate the application of LAPVAS. It is demonstrated that the LAPVAS has a good performance in the land surface remote sensing product validation.  相似文献   

Catastrophic debris flows triggered by the 20 August 2019 rainfall,a decade since the Wenchuan earthquake,China     

Yang  Fan  Fan  Xuanmei  Siva Subramanian  Srikrishnan  Dou  Xiangyang  Xiong  Junlin  Xia  Bing  Yu  Zongyang  Xu  Qiang 《Landslides》2021,18(9):3197-3212

Landslides - Enhanced debris flow activity observed after the 2008 Wenchuan earthquake, Sichuan Province, SW China, is still intense more than a decade since the earthquake. A heavy rainstorm on 20...  相似文献   

Geothermal energy exploitation from depleted high-temperature gas reservoirs by recycling CO2:The superiority and existing problems     

Guodong Cui  Shaoran Ren  Bin Dou  Fulong Ning 《地学前缘(英文版)》2021,12(6):428-443

CO2 can be used as an alternative injectant to exploit geothermal energy from depleted high-temperature gas res-ervoirs due to its high mobility and unique thermal properties.However,there has been a lack of systematic anal-ysis on the heat mining mechanism and performance of CO2,as well as the problems that may occur during geothermal energy exploitation at specific gas reservoir conditions.In this paper,a base numerical simulation model of a typical depleted high-temperature gas reservoir was established to simulate the geothermal energy exploitation processes via recycling CO2 and water,with a view to investigate whether and/or at which condi-tions CO2 is more suitable than water for geothermal energy exploitation.The problems that may occur during the CO2-based geothermal energy exploitation were also analyzed along with proposed feasible solutions.The re-sults indicate that,for a depleted low-permeability gas reservoir with dimensions of 1000 m × 500 m × 50 m and temperature of 150℃using a single injection-production well group for 40 years of operation,the heat mining rate of C02 can be up to 3.8 MW at a circulation flow rate of 18 kg s-1 due to its high mobility along with the flow path in the gas reservoir,while the heat mining rate of water is only about 2 MW due to limitations on the injectivity and mobility.The reservoir physical property and injection-production scheme have some effects on the heat mining rate,but CO2 always has better performance than water at most reservoir and operation condi-tions,even under a high water saturation.The main problems for CO2 circulation are wellbore corrosion and salt precipitation that can occur when the reservoir has high water saturation and high salinity,in which serious salt precipitation can reduce formation permeability and result in a decline of CO2 heat mining rate(e.g.up to 24％reduction).It is proposed to apply a low-salinity water slug before CO2 injection to reduce the damage caused by salt precipitation.For high-permeability gas reservoirs with high water saturation and high salinity,the supe-riority of CO2 as a heat transmission fluid becomes obscure and water injection is recommended.  相似文献   

社区增权视角下文化遗产地治理路径优化     

陈新新  李伯华  窦银娣  谭红日  刘沛林 《热带地理》2022,42(1):100-112

以湖南省龙山县惹巴拉村寨为例,采用文本分析法与深度访谈法,基于社区增权视角,优化文化遗产地治理路径。结果发现：1）文化遗产地社区失权体现在经济失权、心理失权、社会失权及政治失权4个方面。2）文化遗产地通过权力合作、权力共有及权力激励等社区赋权方式再分配资源、权益及资本。3）权力共有路径下,强化政策透明度和社区话语权,有助于社区主体参与治理;权力合作路径下,扩充资源分配渠道、强化主体合作关系,有助于社区治理渠道扩展;权力激励路径下,规范治理主体、治理对象及监管方式,有助于社区治理政策细化。文章借助“社区增权”理论,将旅游引发的“社区失权”改进为“社区增权”,补充完善文化遗产地治理研究,可为其他少数民族文化遗产地的治理提供参考。  相似文献   

南极内陆科研观测舱体内部保障与控制系统的应用与研究     

李聪克  李丙瑞  王焘  陈燕  窦银科  姚旭  王煜尘 《极地研究》2022,34(2):198-209

  相似文献   

Application of otolith shape analysis for stock discrimination and species identification of five goby species （Perciformes： Gobiidae） in the northern Chinese coastal waters   总被引：1，自引：0，他引：1  

于鑫  曹亮  刘金虎  赵博  单秀娟  窦硕增 《中国海洋湖沼学报》2014,32(5):1060-1073

We tested the use of otolith shape analysis to discriminate between species and stocks of five goby species( Ctenotrypauchen chinensis, Odontamblyopus lacepedii, Amblychaeturichthys hexanema, Chaeturichthys stigmatias, and Acanthogobius hasta) found in northern Chinese coastal waters. The five species were well differentiated with high overall classification success using shape indices(83.7%), elliptic Fourier coefficients(98.6%), or the combination of both methods(94.9%). However, shape analysis alone was only moderately successful at discriminating among the four stocks(Liaodong Bay, LD; Bohai Bay, BH; Huanghe(Yellow) River estuary HRE, and Jiaozhou Bay, JZ stocks) of A. hasta(50%–54%) and C. stigmatias(65.7%–75.8%). For these two species, shape analysis was moderately successful at discriminating the HRE or JZ stocks from other stocks, but failed to effectively identify the LD and BH stocks. A large number of otoliths were misclassified between the HRE and JZ stocks, which are geographically well separated. The classification success for stock discrimination was higher using elliptic Fourier coefficients alone(70.2%) or in combination with shape indices(75.8%) than using only shape indices(65.7%) in C. stigmatias whereas there was little difference among the three methods for A. hasta. Our results supported the common belief that otolith shape analysis is generally more effective for interspecific identification than intraspecific discrimination. Moreover, compared with shape indices analysis, Fourier analysis improves classification success during inter- and intra-species discrimination by otolith shape analysis, although this did not necessarily always occur in all fish species.  相似文献   

遥感SST产品误差在海-气CO2通量计算中的传递及贡献分析     

窦文洁 《海洋与湖沼》2014,45(1):148-156

海-气界面CO2通量的估算对于碳的生物地球化学循环和全球气候变化等研究具有重要的意义,利用遥感手段是进行全球尺度海表面碳通量估算的唯一手段,但是由于不确定性的存在限制了海-气界面CO2通量遥感估算产品在决策应用上的可靠性。本文通过建立海-气界面CO2通量直接控制参量(气体交换速率k、海表面CO2溶解度S和海表面CO2分压pCO2sw)误差结构图,以通量估算的主要影响因子—海表温度（SST）为例,建立了SST在通量计算中的误差传递流程图,并采用Monte Carlo方法模拟了SST误差在通量计算中的传递规律和对最终误差的贡献。结果表明在遥感SST误差为0.5℃并为正态分布的假设下,误差在k、S计算中的传递为指数分布和近似指数分布,而在pCO2sw模型计算中为正态分布,最终在通量FCO2中的传递为指数分布;在大气CO2分压为固定值370μatm的情况下,SST对最终的通量结果带来的误差为1.2mmol?m-2?day-1左右。本文以SST为例,提供了一种通量计算中遥感参数误差传递和贡献的计算方法,可以为其他遥感获取的参量提供分析依据和参考。  相似文献   

One hundred-year sedimentary record of heavy metal accumulation in the southeastern Liaodong Bay of China   总被引：2，自引：1，他引：1  

Jingtao Zhao  Bangqi Hu  Jun Li  John Yang  Fenglong Bai  Yanguang Dou  Xuebo Yin 《Environmental Earth Sciences》2014,71(3):1073-1082

Integrated analyses of grain size, ²¹⁰Pb stable isotope, and heavy metals were performed to characterize the sedimentary core LDC30 collected from the southeastern Liaodong Bay of China and investigate the 100-year history of heavy metal accumulation. The aluminum-normalized enrichment factors and the excess metal fluxes (MF_xs) indicated that the metal accumulation in the southeastern Liaodong Bay occurred in three stages: a pre-industrial stage (prior to 1960s) with natural accumulation, an initial industrial stage (1960–1990) with slowly elevated accumulation, and an industrialized stage (post-1990s) with accelerated accumulation. A moderate enrichment of Cd and Pb (up to 4.1- and 2.6-fold over the baseline, respectively) and a slight enrichment of Cr, Cu, Ni, and Zn (up to 1.3-fold) were measured in the recent sediments. Multivariate analysis demonstrated that the Cr, Cu, Ni, and Zn were from the natural origin, whereas Cd and Pb from the anthropogenic origin. The MF_xs of Cd and Pb showed a drastically increasing trend since 1990s, which could result from the intensive application of fertilizers and combustion of fossil fuels.  相似文献   

闪电定位数据快速传输的通信应用     

窦以文  屈玉贵  宛霞  史君卿  燕东渭 《气象科技》2007,35(4):293-596

北京市气象局是国内首次使用SAFIR3000闪电定位系统的用户。闪电定位系统对数据的传输实时要求很高,而国内通信线路和国外通信线路有些差别,选择合理有效的传输方式对提高闪电定位系统的应用非常重要。闪电定位系统实时数据的传输方法有很多种。目前主要有专线接入传输方式、Internet和无线通信相结合的VPN接入传输方式、Internet转发传输方式,这些通信方法是实时采集气象数据非常有效的手段。北京市气象局的闪电定位系统采用的是Internet转发传输方式。  相似文献   

An iterative wavefront sensing algorithm for high-contrast imaging systems     

Jiang-Pei Dou  De-Qing Ren  Yong-Tian Zhu 《中国天文和天体物理学报》2011,11(2)

Wavefront sensing from multiple focal plane images is a promising technique for high-contrast imaging systems.However,the wavefront error of an optics system can be properly reconstructed only when it is very small.This paper presents an iterative optimization algorithm for the direct measurement of large static wavefront errors from only one focal plane image.We first measure the intensity of the pupil image to get the pupil function of the system and acquire the aberrated image on the focal plane with a p...  相似文献