“全球生态系统碳循环关键参数立体观测与反演”项目概述与研究进展

准确评估全球碳循环是准确估算未来大气CO₂浓度、预测气候变化的关键。目前全球陆地与海洋碳源汇估算时空不确定性大。除碳循环模式理论和认知存在缺陷外,全球尺度上缺乏精细时空分辨率的生态系统碳循环参数观测数据是造成全球碳循环估算存在巨大不确定性的重要原因之一。为此,项目以立体观测为技术手段,通过协同全球台站观测资料和多源卫星遥感数据,研制要素齐全的高质量陆地与海洋生态系统碳循环关键参数产品（GLOCC）,不仅包括主要碳源汇直接观测产品,如陆地生态系统生产力、生物量、土壤碳库和海水二氧化碳分压、海水颗粒有机碳等;还包括陆地与海洋生态系统光合作用关键参数以及碳循环模型过程关键变量。项目执行3 a多来,收集与处理了1981~2019年来的28种国内外卫星数据和19种全球碳循环产品生产相关的全球遥感产品,攻克了多源卫星遥感数据的一致性处理关键技术,发展了陆地与海洋生态系统碳循环关键参数的高精度卫星反演关键技术,初步研制了GLOCC碳参数产品生产与共享平台,并通过集成国内外卫星遥感数据,将部分陆地生态系统碳参数的时间分辨率从8 d提高到5 d。目前已经有7个GLOCC产品在国内外多个数据中心提供了产品共享服务。项目预期能够为全球变化研究提供时空分辨率高、时间序列长、碳循环参数全的遥感产品,并服务于全球碳源汇准确估算需求,并提供全球和区域碳收支的重要科学数据。     

卫星全球普查任务调度系统的设计与实现

卫星全球普查任务是指利用星载遥感设备,周期性地对全球表面进行覆盖监测和数据采集。论文针对卫星全球普查任务需求的特点和卫星资源能力,建立了卫星全球普查任务调度系统。卫星全球普查任务调度系统主要包括想定管理模块、资源管理模块、场景管理模块、调度模块与仿真评估模块等功能模块,文中重点分析了系统核心的场景管理模块、调度模块与仿真评估模块的实现。     

对地观测卫星协同观测区域目标方法研究

对地观测区域目标分割与优选问题是多星协同观测区域目标规划过程中的一个重要环节。采用卫星或遥感器侧摆能力的区域目标动态分割算法,并结合贪婪优化算法对分割结果进行优化规划,在规划过程中依据建立的全球网格参考系统可以方便、高效地计算目标覆盖率,进行实时效能评估以对分割方式进行反馈调整,保证区域目标分割结果最优。依据提出的算法设计了包含三颗对地卫星和一个区域观测目标的应用场景进行实例仿真,并得出了较为理想的仿真结果。     

多卫星区域观测任务的效率优化研究

多颗对地观测卫星对区域目标进行观测的效率优化问题涉及到时间窗口、存储容量、地面分辨率等诸多因素,是一个十分复杂的优化问题。在分析该问题的特点的基础上,首先对原始数据进行仿真预处理,通过STK仿真软件计算处理难以量化的时间窗口等复杂的约束条件;然后在仿真的输出数据的基础之上建立数学优化模型。在模型求解问题上,通过对问题特点的分析,提出并实现了遗传算法。最后通过一个想定实例验证了模型和算法的求解的有效性。     

国际卫星对地观测委员会（CEOS）18届全会、CEOS20周年庆典及国际对地观测技术与应用研讨会和展览会在北京隆重举行

11月16日，由中国科技部、国家航天局主办。国家遥感中心、中国空间技术研究院、中国科技交流中心和CEOS中国秘书处共同承办的CEOS18届全会、CEOS20周年庆典及国际对地观测技术与应用研讨会和展览会在北京中国国际贸易中心隆重开幕。世界各国负责对地观测的相关机构、国际科技组织的官员和专家学600余人汇集北京，共同交流全球对地观测技术及其应用的最新进展，     

我国对地观测的总需求和现有基础

我国空间应用有许多方面，对地观测仅是其一，它们的重要性和发展次序的决定因素之一就是国家和社会的总需求。有关对地观测需求的文献，以往比较分散，本文在分析、归纳这些分散需求的基础上，提出一篇综合性论文，以供有关部门和决策者参考。同时，我们也提出我国对地观测方面的现有基础的内容，虽难说全面，却理出了头绪，或有参考价值。     

我国对地观测的总需求和现有基础

我国空间应用有许多方面，对地观测仅是其一，它们的重要性和发展次序的决定因素之一就是国家和社会的总需求。有关对地观测需求的文献，以往比较分散，本文在分析、归纳这些分散需求的基础上，提出一篇综合性论文，以供有关部门和决策者参考。同时，我们也提出我国对地观测方面的现有基础的内容，虽难说全面，却理出了头绪，或有参考价值。     

对地观测卫星的多目标分配方法

卫星在进行短期对地观测任务时,需要将有限的卫星观测资源(对地观测的有效载荷)分配给多个地面目标,从而使观测所得的总信息量最大,或者得到某个准则下最优的信息增益,有必要对此进行研究:建立起评估卫星对地观测效果的效能模型,并对所观测目标进行排序,从而得到关于多目标的卫星分配模型.模型以可见光观测卫星为例,考虑了卫星对目标观测效果有影响的四类主要因素,提出了一种基于信息熵与隶属函数的处理方法,可作为卫星目标观测体系需求分析、顶层设计以及效能评估的依据.最后以一个仿真实例说明了模型的适用性.     

基于两阶段迭代优化的空天观测资源协同任务规划方法

为提高空天观测资源协同观测能力,基于分而治之框架,提出一种两阶段迭代优化方法以解决空天观测资源协同任务规划问题.第1阶段,根据观测机会和冲突度构造适应度函数,基于适应度将任务分配到合适的子规划中心;第2阶段,子规划中心根据分配到的任务进行资源调度,得到各类观测资源的观测计划,并将资源观测方案和观测收益反馈给第1阶段.第...     

基于PDDL的对地观测卫星任务规划建模研究

传统的数学模型方法是解决复杂卫星任务规划问题的一种途径,但其抽象性给建模人员带来很大难度。PDDL(Planning Domain Definition Language)可以针对卫星任务规划问题建立清晰有效的模型,并能把模型的知识转化成计算机易于接受的形式。用PDDL描述对地观测卫星的任务规划问题,分析了卫星执行任务时涉及的约束、相关活动和所需的资源,建立任务规划模型的域文件(domain file)和问题(problem file)文件,并针对所建模型提出求解模型的算法流程,最后通过一个算例验证模型和算法是有效地。     

冻融过程与陆地生态系统碳循环的相互关系研究进展

全球变化与可持续发展研究是当今地学研究的两大主题,陆地生态系统碳循环对全球变化影响重大。冻土中的碳储量占据全球陆地碳储量的重要份额,它对气候变化十分敏感,是气候变化的指示器,研究冻土地区土壤的冻融过程及其与陆地生态系统碳循环之间的相互关系对于全球变化研究具有重要意义。在总结冻融对碳循环过程影响机理的基础上,回顾了国内外关于冻融影响下碳循环模拟研究的主要进展,指出了其存在的主要问题,并对未来冻融与碳循环研究发展趋势做了初步的展望。     

Global citizenship education,school curriculum and games: Learning Mathematics,English and Science as a global citizen

Based on an account of how two classes of primary five students in Singapore engage in the learning of English, Mathematics and Science by playing the role of global citizens, the paper suggests an alternative but realistic approach to teaching global citizenship education. Set against the back story of Atlantis facing ecological, social and cultural decay due to the blind pursuit of prosperity and modernisation by its rulers, each student became a quester called on to save Atlantis. Throughout the mission they were presented with different problems in Atlantis (similar to existing global issues) and were expected to research and suggest solutions to the problems by alone or with fellow questers. These problems were tied to the primary five English, Mathematics and Science curriculum. Through documenting and making sense of these activities via observations, interviews and pre-post questionnaire surveys, the paper shows how the new approach may enhance the learning engagement, academic motivation and social commitments among the students. We also explore the sustainability and scalability of such an approach in the school system and highlight constraints. The paper then draws implications for global citizenship education in schools that include designing a meaningful context for engaged learning in schools with components of global citizenship, developing a research culture in schools as a stepping stone for global citizenship education and building capacity of teachers and school leaders in global citizenship.     

基于“3S”技术的县级土地资源动态监测技术系统

土地资源日新月异的变化使得传统的土地资源管理手段无法满足土地资源信息及时更新的要求。探讨了利用遥感、地理信息系统和全球定位系统为代表的“3S”技术进行县级土地资源动态监测和更新的原理和方法。遥感是进行土地利用变化动态监测,发现土地利用变化区域的主要手段。全球定位系统接收仪用于对变化区域进行现场精确定位和实测。实测的变更数据可用于对原有的地理信息系统本底数据库进行修改,从而完成对土地资源的动态监测和数据库的及时更新。福清市土地资源动态监测技术系统就是利用“3S”技术建立起来的业务运行系统。系统所具备的功能可以满足县级土地资源的动态监测和及时更新。     

The data-based mechanistic approach to the modelling, forecasting and control of environmental systems

The paper presents a unified approach to the modelling, forecasting and control of natural and man-made environmental systems. The modelling approach exploits the author’s Data-Based Mechanistic (DBM) modelling philosophy, combined with powerful methods of recursive statistical estimation. These provide the basis for two major stages of model building: first, the critical evaluation of the over-parametrized simulation models that are currently the most common vehicle used in environmental planning and management studies; and second, the adaptive, data-based estimation of parsimonious, ‘top-down’ models that can be used for adaptive forecasting and data assimilation, as well as operational control and management system design. The associated control system design methodology is based on the Non-Minimal State Space (NMSS) approach to the design of Proportional-Integral-Plus (PIP) control systems, based on the DBM models obtained at the previous modelling stage. The paper includes a case study concerned with the modelling and control of globally averaged levels of CO₂ in the atmosphere.     

耕作对旱区坡耕地土壤碳素转化及冬小麦产量的影响

利用长期定位试验(1999开始保护性耕作,2004年采样测定),在豫西旱区坡耕地上进行了不同耕作对土壤有机碳、微生物态碳及水分利用效率的影响研究。结果表明:深松覆盖和免耕覆盖处理的耕层有机碳增加较明显,以深松覆盖有机碳含量最高为6.79gkg-1,比传统耕作高13.82%,其次是免耕,较传统高11.58%,而少耕却较传统降低了1.38%,随着土层的加深,土壤有机碳含量降低,0～60cm有机碳平均值,深松和免耕较传统分别增加了14.08%、5.41%,少耕较传统减少1.12%。土壤微生物碳对耕作敏感,其含量免耕>深松>传统>少耕,分别为206.87mgkg-1、138.43mgkg-1、115.42mgkg-1和112.57mgkg-1,较传统增加79.3%、19.9%和-2.5%。土壤有机碳和土壤微生物态碳都有坡下富集现象。少耕、免耕、深松和传统的SMBC/SOC的值分别为1.91%、3.11%、2.04%和1.93%,免耕和深松对培肥地力、改善环境有好的应用前景;同时免耕覆盖与深松覆盖可提高产量,增产分别达10.22%与9.26%;可提高水分利用效率。     

Developing Elements of User Experience for Mobile Phones and Services: Survey,Interview, and Observation Approaches

The term user experience (UX) encompasses the concepts of usability and affective engineering. However, UX has not been defined clearly. In this study, a literature survey, user interview and indirect observation were conducted to develop definitions of UX and its elements. A literature survey investigated 127 articles that were considered to be helpful to define the concept of UX. An in‐depth interview targeted 14 hands‐on workers in the Korean mobile phone industry. An indirect observation captured daily experiences of eight end‐users with mobile phones. This study collected various views on UX from academia, industry, and end‐users using these three approaches. As a result, this article proposes definitions of UX and its elements: usability, affect, and user value. These results are expected to help design products or services with greater levels of UX. © 2011 Wiley Periodicals, Inc. This article was published online on 20 October 2011. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 13 June 2013.     

一种新的启发式优化算法——五行环优化算法研究与分析

借鉴中国古代哲学理论所描述的系统动态平衡方法, 提出了解决连续函数优化问题的五行环优化算法.首先, 分析了基于五行元素生克原理而建立的五行环模型, 并在该模型基础上, 构建了元素空间结构以及元素更新方法等关键环节, 从而实现了五行环优化算法.随后, 对五行环优化算法进行了性能分析和关键参数比较, 针对标准测试函数, 将五行环优化算法与其他17个机制各异的启发式优化算法进行了比较, 实验结果验证了五行环优化算法的有效性和通用性, 也表明了其在求解连续函数优化问题上具有较好的优化性能.     

Effects of spectral response function on surface reflectance and NDVI measured with moderate resolution satellite sensors: Extension to AVHRR NOAA-17, 18 and METOP-A

This work extends the previous study of Trishchenko et al. [Trishchenko, A. P., Cihlar, J., & Li, Z. (2002). Effects of spectral response function on surface reflectance and NDVI measured with moderate resolution satellite sensors. Remote Sensing of Environment 81 (1), 1-18] that analyzed the spectral response function (SRF) effect for the Advanced Very High Resolution Radiometer (AVHRR) onboard the NOAA satellites NOAA-6 to NOAA-16 as well as the Moderate Resolution Imaging Spectroradiometer (MODIS), the VEGETATION sensor (VGT) and the Global Imager (GLI). The developed approach is now applied to cover three new AVHRR sensors launched in recent years on NOAA-17, 18, and METOP-A platforms. As in the previous study, the results are provided relative to the reference sensor AVHRR NOAA-9. The differences in reflectance among these three radiometers relative to the AVHRR NOAA-9 are similar to each other and range from − 0.015 to 0.015 (− 20% to + 2% relative) for visible (red) channel, and from − 0.03 to 0.02 (− 5% to 5%) for the near infrared (NIR) channel. The absolute change in the Normalized Difference Vegetation Index (NDVI) ranged from − 0.03 to + 0.06. Due to systematic biases of the visible channels toward smaller values and the NIR channels toward slightly larger values, the overall systematic biases for NDVI are positive. The polynomial approximations are provided for the bulk spectral correction with respect to the AVHRR NOAA-9 for consistency with previous study. Analysis was also conducted for the SRF effect only among the AVHRR-3 type of radiometer on NOAA-15, 16, 17, 18 and METOP-A using AVHRR NOAA-18 as a reference. The results show more consistency between sensors with typical correction being under 5% (or 0.01 in absolute values). The AVHRR METOP-A reveals the most different behavior among the AVHRR-3 group with generally positive bias for visible channel (up to + 5%, relative), slightly negative bias for the NIR channel (1%-2% relative), and negative NDVI bias (− 0.02 to + 0.005). Polynomial corrections are also suggested for normalization of AVHRR on NOAA-15, 16, 17 and METOP-A to AVHRR NOAA-18.     

Design, development and implementation of a global information warehouse: a case study at IBM

The characteristics of a global information warehouse (GIW) can be understood with reference to the three dimensions implied by the three words in its name. These dimensions are boundary of the system, semiotic level of the objects in the system, and organization of objects in the system, corresponding to the terms 'global', 'information' and 'warehouse', respectively. This paper defines these three dimensions and describes the system characteristics that flow from the definitions. These characteristics also highlight the issues involved in the design, development and implementation of GIWs. The case study following the discussion of the three dimensions illustrates these issues.