Calculation of Ecological Footprint Based on Modified Method and Quantitative Analysis of Its Impact Factors ——A Case Study of Shanghai     

GAO Chengkang JIANG Dahe WANG Dan YAN Jonathan 《中国地理科学(英文版)》2006,16(4):306-313

1 Introduction The publication of UNDPI (The United Nation Devel- opment and Planning Indices) in May 1990 has brought about an on-going search for the system of “sustainable development”, which is also one of hot topics in China (Wackernagel et al., 1999; Vuuren and Smeets, 2000). Regretfully, the difficulty in quantifying sustainable de- velopment resulted in a slow progress in those researches. In the past a few years, however, ecological footprint (EF) analysis (Rees, 1992; Wackn…  相似文献   

天文用2K×2K高速CMOS相机的研制与测试结果   总被引：3，自引：0，他引：3  

李丹  尚媛园  宋谦 《天文研究与技术》2006,3(4):380-386

高性能CMOS成像器件的技术近年来发展迅速,与长期在天文观测中占统治地位的CCD器件相比,CMOS在读出速度、功耗、空间应用的可靠性等方面具有一定的优势。为了探索CMOS成像器件在天文领域中的应用,我们以Fillfactory公司最新的高速、大面阵CMOS芯片LUPA 4000为基础,研制了一台天文相机并对其进行了测试。本文简要介绍了CMOS成像器件的概述,相机软、硬件系统的组成,以及在实验室条件下得到的读出噪声、增益、线性和增益等若干测试结果。  相似文献   

不协调决策表的规则提取     

朱六兵  周丹  杨斌 《成都信息工程学院学报》2006,21(3):385-389

对决策表数据的性质、数据之间的关系进行了讨论,并由此对决策表进行了分类.讨论了不协调决策表的数据约简,并证明其不影响属性约简和规则提取.基于数据的协调性,对不协调决策表的属性约简进行了研究,并提出了一种规则提取方法.最后,用实例验证了方法的有效性.  相似文献   

The redshift distribution of type Ia supernovae: constraints on progenitors and cosmic star formation history     

Avishay Gal-Yam †  Dan Maoz 《Monthly notices of the Royal Astronomical Society》2004,347(3):942-950

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Distribution and composition of phytoplankton in northeastern coastal waters of the United States     

Harold G. Marshall  Myra S. Cohn 《Estuarine, Coastal and Shelf Science》1983,17(2):119-131

Results are given from collections made during eight cruises over the northeastern continental shelf. Seasonal phytoplankton assemblages are noted, which include a variety of ultraplankton components. Areas of greatest cell concentrations were at near shore stations, Georges Bank, and at scattered sites over the shelf. Dominant species included Skeletonema costatum, Asterionella glacialis and Leptocylindrus danicus.  相似文献   

URBANIZATION AND ITS IMPACTS ON WATER ENVIRONMENT IN TUMEN RIVER BASIN   总被引：1，自引：0，他引：1  

WANGShi－jun  WANGDan 《中国地理科学(英文版)》2002,12(3):273-281

１INTRODUCTIONUrbanizationisaprocessthatallowspopulationandindustrytohighlyconcentrate．Itisinevitablethatthiskindofprocesswillhavedeepimpactsoneco－environment．TheTumenRiverisaninternationalwaterbody．ScopeoftheTumenRiverBasin（TRB）canbedefinedas（only  相似文献   

A Multi-Angle Averaging Theorem Applied to the J2 Problem     

Cătălin Cucu-Dumitrescu  Dan Şelaru 《Celestial Mechanics and Dynamical Astronomy》1997,69(3):255-270

A particular multi-angle averaging theorem for systems admitting a finite Fourier expansion of the field is presented, together with its application to the problem of motion around an oblate planet (the J₂ problem), in harmonic oscillator formulation. This method of approximate integration has the advantage of working with (close on) directly measurable elements. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

高空槽脊对台风“天兔”（0705）变性过程中非对称降水的影响     

吴丹  黄泓  王春明  马申佳 《大气科学》2021,45(2):355-368

本文基于NCEP再分析资料、TRMM卫星降水资料和RSMC最佳路径集（Best-track Dataset）资料,分析了热带气旋（TC）“天兔”变性过程中降水分布和大尺度环流的演变,并结合片段位涡反演进行修改槽脊的数值试验,研究了环流调整对TC变性过程中非对称降水的影响。结果表明:（1）“天兔”变性前降水集中在路径左侧,伴随着纬向型向经向型调整的背景环流,副热带高压南退的同时减弱西进;（2）TC降水的非对称分布与冷暖锋的相对强弱、水汽输送情况以及高空冷空气下传的落区有直接关系;（3）加强环流调整后,系统斜压性加强,与LOT（降水集中于TC路径左侧）型降水相关的环流指数增大过程随之加强,有利于LOT型降水分布进一步加强。  相似文献   

拉萨夏季大气边界层气溶胶垂直结构特征     

李若羽  卞建春  唐贵谦  李丹  白志宣  毛文书 《大气科学》2022,46(3):666-676

大气污染物的垂直梯度观测是识别区域输送和本地贡献的必要手段。基于此,2020年8月在拉萨市利用光学粒子计数器（the Printed Optical Particle Spectrometer,简称POPS）在地面和系留气艇分别对0.13～3.39 μm粒径范围的气溶胶数浓度进行了测定。结果表明:（1）拉萨近地面气溶胶数浓度在16 cm?3到870 cm?3范围之间,比华北和珠江三角洲地区小2～3个量级;（2）气溶胶数浓度呈现两峰两谷的日变化结构,峰值通常以0.13～0.4 μm的小粒径粒子为主,且对应北京时间早（10:00）、晚（21:00）高峰时段;（3）气溶胶数浓度垂直分布与边界层演变密切相关,稳定边界层中的气溶胶随高度递减,粒子数浓度为194±94 cm?3,对流边界层和残留层中的气溶胶分布均一,数浓度分别为165±99 cm?3和123±95 cm?3,且显著低于稳定边界层。以上研究结果表明,拉萨的污染源主要为局地机动车排放,机动车污染物减排是打造高原生态旅游城市的必由之路。  相似文献   

Development of a parameterization for simulating the urban temperature hazard using satellite observations in climate model   总被引：1，自引：1，他引：0  

Menglin Jin  J. Marshall Shepherd  Christa Peters-Lidard 《Natural Hazards》2007,43(2):257-271

Urban surface temperature is hazardously higher than surrounding regions (so-called urban heat island effect UHI). Accurately simulating urbanization-induced temperature hazard is critical for realistically representing urban regions in the land surface-atmosphere climate system. However, inclusion of urban landscapes in regional or global climate models has been overlooked due to the coarse spatial resolution of these models as well as the lack of observations for urban physical properties. Recently, National Aeronautics and Space Administration (NASA) Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) observations illustrate important urban physical properties, including skin temperature, surface albedo, surface emissivity, and leaf area index, It is possible to identify the unique urban features globally and thus simulate global urban processes. An urban scheme is designed to represent the urban-modified physical parameters (albedo, emissivity, land cover, roughness length, thermal and hydraulic properties) and to include new, unique physical processes that exist in urban regions. The urban scheme is coupled with National Center for Atmospheric Research (NCAR) Community Land Model Version 2 (CLM2) and single column coupled NCAR Community Atmosphere Model CAM2/CLM2 to assess the mechanisms responsible for UHI. There are two-steps in our model development. First, satellite observations of albedo, emissivity, LAI, and in situ observed thermal properties are updated in CLM2 to represent the first-order urban effects. Second, new terms representing the urban anthropogenic heat flux, storage heat flux, and roughness length are calculated in the model. Model simulations suggest that human activity-induced surface temperature hazard results in overlying atmosphere instability and convective rainfall, which may enhance the possibility of urban flood hazard.

Menglin JinEmail:

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