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51.
陆地表层地质环境质量综合评价与地质灾害系统分析——以广东沿海地带为例 总被引:3,自引:0,他引:3
将广东沿海陆地表层地质环境划分为构造稳定性、坡面稳定性和地基稳定性三个评价层面 ,其中包括由 9个指标构成的评价指标体系 ;确定了各指标的权重和五级分级标准和环境质量的五级标准 ;使用模糊数学综合评价模型将广东沿海 190个评价单元划分为 2 2个地质环境质量区。在灾害基本数据库和灾害时空分布分析的基础上 ,划分了 9个地质灾害一级分区及 32个二级分区 ,确定了地质环境、气候气象和人为活动因素三大类致灾主控因子 ;构造了三种地质灾害系统的概念模型和灾害预测指标体系框架 ,建立了地质灾害地理信息系统。 相似文献
52.
关于若干化探数据处理方法的讨论 总被引:11,自引:3,他引:11
化探数据处理中的系统误差校正和异常识别方法很多,移动标准化法、分区标准化法和衬度系数法是其中的几种方法,主要对这几种方法做了简单的介绍并对其效果进行了对比,最后着重讨论了C型变换法的优点。 相似文献
53.
Wang Zonghao Mao Jianping Huang Jihong Arnold Gruber Albert Thomasell Tan Sun Chen 《Acta Meteorologica Sinica》1992,6(4):421-432
This paper is to examine the impact of satellite data on the systematic error of operational B-model in China.Em-phasis is put on the study of the impact of satellite sounding data on forecasts of the sea level pressure field and 500 hPaheight.The major findings are as follows.(1)The B-model usually underforecasts the strength of features in the sea level pressure(SLP)field,i.e.pressuresare too low near high pressure systems and too high near low pressure systems.(2)The nature of the systematic errors found in the 500 hPa height forecasts is not as clear cut as that of the SLPforecasts,but most often the same type of pattern is seen,i.e.,the heights in troughs are not low enough and those inridges are not high enough.(3)The use of satellite data in the B-model analysis/forecast system is found to have an impact upon the model'sforecast of SLP and 500 hPa height.Systematic errors in the vicinity of surface lows/500 hPa troughs over the oceansare usually found to be significantly reduced.A less conclusive mix of positive and negative impacts was found for allother types of features. 相似文献
54.
1962—1986年JYD1968.0地极坐标的均匀化及其与BIH的比较 总被引:2,自引:0,他引:2
本文研究了1962-1986年JYD1968.0地极坐标均匀中星表系统差,章动系列的变动和光行星常数变动的影响,并将经过改正后的JYD1968.0地极坐标系统和BIH系统作了比较。 相似文献
55.
The 3-hour-interval prediction of ground-level temperature from 00 h out to 45 h in South Korea(38 stations) is performed using the DLM (dynamic linear model) in order to eliminate the systematic error of numerical model forecasts. Numerical model forecasts and observations are used as input values of the DLM. According to the comparison of the DLM forecasts to the KFM (Kalman filter model) forecasts with RMSE and bias, the DLM is useful to improve the accuracy of prediction. 相似文献
56.
57.
利用RPC模型进行IKONOS影像的精确定位 总被引:1,自引:0,他引:1
研究了IKONOS卫星影像基于RPC模型的立体定位算法与区域网平差方法.针对立体定位计算过程中RPC(Rational Polynomial Coefficients)模型存在的系统性误差,给出了物方和像方补偿方案.实验结果表明,各种补偿方案均可有效消除RPC模型的系统误差,取得优于1.3 m的定位精度;区域网平差的定位精度可达1.1 m,是最理想的定位方法. 相似文献
58.
Boriana Deliiska 《Transactions in GIS》2007,11(4):637-651
Geoinformatics is a comparatively new interdisciplinary science and as a part of space informatics uses methods and terminology of informatics and many natural sciences. An ontology of geoinformatics is discussed in the paper, especially concerning its structure, relationships with other ontologies, resources for development and utilization. The ontology of geoinformatics is a kind of domain ontology and has a layered structure consisting of syntactic and semantic layers. The corpus of this ontology is an existing multilingual dictionary of geographical information systems (GIS) enriched with terminology from other external sources. The building of the ontology is preceded by the development of a taxonomy and thesaurus of geoinformatics. The thesaurus database is converted into an OWL ontology by a Visual Basic application. The reusing of the ontology is proposed by its transformation in application ontologies for geoinformatics education. 相似文献
59.
KAYA Murat ALTINDAG Ahmet 《中国海洋湖沼学报》2007,25(4):423-426
Thirteen rotifer species belonging to the families Lepadellidae and Trichocercidae were studied taxonomically from nine water bodies in Turkey. Lepadella biloba is a new entry to the Turkish rotifer fauna. All species were drawn under a light microscope using a camera lucida. 相似文献
60.
Integrative taxonomic description of Plakina kanaky,a new polychromatic sponge species from New Caledonia (Porifera: Homoscleromorpha)
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César Ruiz Julijana Ivanišević Pierre Chevaldonné Alexander V. Ereskovsky Nicole Boury‐Esnault Jean Vacelet Olivier P. Thomas Thierry Pérez 《Marine Ecology》2015,36(4):1129-1143
Four similar sponges of different colors, all unknown to science, were collected in submarine caves of New Caledonia. We aimed at determining whether the four chromotypes represented different species or phenotypic variations of a unique new species. We used an integrative taxonomic approach combining morphologic, molecular and metabolomic analyses. The main traits that define these specimens are a skeleton made of monolophose, trilophose and tetralophose calthrops only, high chemical diversity and a high abundance and diversity of prokaryotic symbionts. The symbiotic community includes two unique prokaryote morphotypes, which are described for the first time in Homoscleromorpha, and appeared to be vertically transmitted. Although several features slightly differ among chromotypes, the most parsimonious conclusion was to propose a single new species Plakina kanaky sp. nov. Our phylogenetic analysis indicated the paraphyly of the Plakina genus, with P. kanaky sp. nov. belonging to a clade that includes Plakina jani and Plakina trilopha. The present work demonstrates that integrative taxonomy should be used in order to revise the entire Plakinidae family and especially the non‐monophyletic genus Plakina. 相似文献