Towards an Open Information Infrastructure for Disaster Research and Management: Data Management and Information Systems Inside DFNK

The development of new and better methods for preventing and managing natural disasters requires a variety of different data sets, covering the range from referenced data, e.g. topographic data and digital elevation models, to various kinds of thematic data, e.g. data about soil, vegetation and land usage as well as monitoring data like precipitation and water levels. So a well-organised data and information management and the implementation of a modern processing environment to acquire, store, analyse and visualise data were decisive for the success of the German Research Network Natural Disasters (DFNK). An information infrastructure was established to support data management and information flows inside the network. A web-based portal offers general information to the public and internal documents, data and software tools to the project community. A catalog service allows the overview of existing but distributed data scombined with flexible data retrieval. Based on internet technology and global standards these concepts contribute to a superior information infrastructure and finally substantiate to the development of Spatial Data Infrastructures (SDI). SDIs aim is to improve availability and usability of spatial data for the manifold application areas. Disaster management is one field depending on a very high level on high-quality data equipment, and on a working SDI.     

Synthetic high-resolution near-IR spectra of the Sun for planetary data reductions made from ATMOS/Spacelab-3 and Atlas-3 data

We have constructed synthetic solar spectra for the 2302-4800 cm⁻¹ (2.08-4.34 μm) range, a spectral range where planetary objects mainly emit reflected sunlight, using ATMOS (Atmospheric Trace Molecule Spectroscopy)/Spacelab-3 and Atlas-3 spectra, of which resolution is 0.01 cm⁻¹. We adopted Voigt line profiles for the modeling of line shapes based on an atlas of line identifications compiled by Geller [Geller, M., 1992. Key to Identification of Solar Features. A High-Resolution Atlas of the Infrared Spectrum of the Sun and the Earth Atmosphere from Space. NASA Reference Publ. 1224, vol. III. NASA, Washington, DC, pp. 1-22], who derived solar line positions and intensities from contaminated high-resolution solar spectra obtained by ATMOS/Spacelab-3. Because the ATMOS spectra in these wavelength ranges are compromised by absorption lines of molecules existing in Earth's high-altitude atmosphere and in the compartment of the spacecraft, the direct use of these high-resolution solar spectra has been inconvenient for the data reductions of planetary spectra. We compared the synthetic solar spectra with the ATMOS spectra, and obtained satisfactory fits for the majority of the solar lines with the exception of abnormal lines, which do not fit with Voigt line profiles. From the model fits, we were able to determine Voigt line parameters for the majority of solar lines; and we made a list of the abnormal lines. We also constructed telluric-line-free solar spectra by manually eliminating telluric lines from the ATMOS spectra and filling the gaps with adjacent continua. These synthetic solar spectra will be useful to eliminate solar continua from spectra of planetary objects to extract their own intrinsic spectral features.     

Disentangling Effective Temperatures of Individual Eclipsing Binary Components by Means of Color-Index Constraining

Eclipsing binary stars are gratifying objects because of their unique geometrical properties upon which all important physical parameters such as masses, radii, temperatures, luminosities and distance may be obtained in absolute scale. This poses strict demand on the model to be free of systematic effects that would influence the results later used for calibrations, catalogs and evolution theory. We present an objective scheme of obtaining individual temperatures of both binary system components by means of color-index constraining, with the only requirement that the observational data-set is acquired in a standard photometric system. We show that for a modest case of two similar main-sequence components the erroneous approach of assuming the temperature of the primary star from the color index yields temperatures which are systematically wrong by ∼ 100K.     

太阳Ⅲ型暴与反向Langmuir波的产生

一般认为,Langmuir波(LW)转换为电磁波是太阳Ⅲ型射电暴的产生机制.由电子束流不稳定性可以很容易地激发LW,正向LW和反向LW的相互作用被认为是产生Ⅲ型暴二次谐波的原因,但反向LW的色散方程和产生机制尚未得到充分研究.对含有温度的双流不稳定性的方程进行了解析求解,发现温度和束流速度分别对反向和正向LW色散关系具有显著影响,并采用粒子模拟(PIC)方法部分证实了解析推导的结果.通过PIC模拟研究了反向LW的产生机制,发现反向LW不能由电子束流直接激发,其能量基本上都是由正向LW散射得到的.然而,电子束流对正向LW的二次谐波有直接放大作用.     

Characteristics of low frequency oscillations of the atmosphere-ocean coupling

The low frequency oscillation of latent heat flux over the tropical oceans has been studied. The NCEP reanalyzed fields of wind and humidity alongwith Reynolds SST are used to compute the instantaneous as well as monthly mean surface latent heat fluxes (LHF) for the year 1999. The procedure of LHF computation is based on bulk method. Spectral analysis shows that significant energy is contained in Madden Julian Oscillation band in the winds, SST, moisture and in the latent heat flux. The global distribution of wind, humidity, SST and LHF oscillation on the time scale of 30–50 days are analyzed. Maximum amplitude of oscillation on this time scale in all the above mentioned parameters were found over the Indian Ocean. The fluctuation of surface wind speed and moisture controls the latent heat flux on this time scale. The fluctuation of SST on this time scale does not seem to be important over most of the oceans.     

基于数据仓库的空间可持续发展决策支持技术研究--以东莞市耕地变化研究为例

以决策支持理论为指导,以遥感和信息系统为技术手段,构造基于数据仓库技术的耕地决策支持系统,以实现多源空间数据的集成、分析、模拟和决策,并以东莞市耕地可持续利用动态研究为例,完成了基于可持续发展研究的因子筛选、模型构建和基于数据仓库的决策分析,探讨了数据仓库技术在空间定量决策分析中的应用,为区域可持续发展研究进行了有益的实践。     

Controlling boundary conditions with a four-dimensional variational data-assimilation method in a non-stratified open coastal model

An innovative way to take the large-scale circulation influence into account in coastal primitive-equation models is explored by an inverse modelling approach. Restricted to barotropic external forcing, this work is a first step in the development of a four-dimensional variational (4DVAR) data-assimilation approach to estimate the best initial and open-boundary conditions that force a coastal model according to interior observations. This development is founded on the OPA modelling system which representation of barotropic coastal dynamics is restricted to motions of long time scales ( a day) due to its rigid lid approximation. Twin experiments are performed in an academic configuration of the Gulf of Lions (located in the northwestern Mediterranean Sea) to study the sensitivity of a remote barotropic forcing to different observational networks measuring surface currents deployed in this area. Three monitoring designs are tested for a large-scale barotropic perturbation in the hindcast mode. It is shown that the space and time distribution of observations acts on the efficiency of the 4DVAR method and then allows coarser datasets.Responsible Editor: Phil Dyke     

实时数据处理系统在乌鲁木齐遥测地震台网中的作用

乌鲁木齐遥测地震台网是目前国内同类台网中孔经最大、直传距离最远的全无线传输网络。对于控制乌鲁木齐及北疆部分地区的地震活动起到重作用。除了传统的模拟信号记录外，实时事件数字采集和相应数据处理系统成为该台网的特色之一。本文将详细介绍该系统的软硬件配置、信道及参数选择、运行功能等方面的情况；最后使用１９９３年９￣１１月发生在相应区域内的地震对采集效果和定位能力进行检验。     

Different levels of macroalgal sampling resolution for pollution assessment

The effects of using reduced sampling resolutions to study macroalgal vegetation patterns have not been studied sufficiently. Here, we test the influence of taxonomic resolution level, removal of occasional species, aggregation of species abundances into functional groups and data transformation in the detection of a long-term recovery process by phytobenthic intertidal assemblages. Results indicate that the aggregation of species data into the genus level has very little influence. Likewise, almost any significant information is lost when occasional algae are removed. Analyses at the level of families and orders still clearly detect differences between highly degraded and reference vegetation. By contrast, analyses based on class and functional group abundances capture quite different information. The effect of transformation is similar at the different taxonomic levels. Most surrogate measures properly reflect changes in diversity. It is concluded that genus level is the most appropriate surrogate approach for detecting the recovery process.     

土地利用更新调查成果内外业一致性检查方法的分析与探讨

土地利用更新调查内外业数据保持一致是确保成果质量的重要环节。本文以福建省开展土地利用更新调查情况为背景,介绍了土地利用更新调查成果内外业一致性检查的方法和过程,分析了不同情况下成果检查的特点,对从事该领域生产和研究的专业人员有一定的借鉴和指导作用。