面向对象的分析模型及其应用     

牛德力  毛国苗 《测绘学院学报》2000,17(2):111-114

介绍了Ｙｏｕｄｏｎ提出的面向对象分析（ＯＯＡ）模型,讨论了在系统分析的阶段难以使用ＯＯＡ的原因,提出了将ＯＯＡ与传统分析技术相结合的系统分析方法和实用步骤,以图库管理的系统分析为例讨论了这种方法的具体应用。  相似文献   

组件式软件及其在GIS开发中的应用   总被引：7，自引：0，他引：7  

牛德力  门葆红 《测绘学院学报》2000,17(4):265-268

介绍了组件技术的基本概念和原理,以图库管理系统为讨论了ＭａｐＸＯＣＸ控件的具体应用方法,少步骤和分发。  相似文献   

Integrity Monitoring of IGEX-98 Data,Part I: Availability     

N. F. Jonkman  K. De Jong 《GPS Solutions》2000,3(4):10-23

The International GLONASS Experiment 1998 (IGEX-98) was the first international tracking campaign of the Russian counterpart to the Global Positioning System (GPS), GLONASS. Started in October 1998, the campaign was originally scheduled to last for three months. However, the launch of additional GLONASS satellites and a widespread enthusiasm among the participants led to an indefinite continuation of the campaign on a “best effort” basis. At the Delft University of Technology, the data of six IGEX-98 stations have been analyzed in detail with integrity monitoring software, developed at the Department of Mathematical Geodesy and Positioning of the University. The software aims to detect outliers and slips in code and phase observations in real time. In addition, the software also allows the validation of the information contained in the broadcast navigation messages. The results of the IGEX-98 data analyses will be presented in a three-part series. In the second part, GLONASS outlier and slips statistics will be discussed, while in the third part the anomaly detection results of the GLONASS and GPS messages will be shown. In this first part of the series, however, the most basic of all statistics will be considered: a simple day-to-day count of the number of GLONASS and GPS observations. Although simple, this statistic yields a surprising amount of information both on the availability of the GLONASS satellites and on the peculiarities of some of the receiver makes participating in the IGEX-98 campaign. ? 2000 John Wiley & Sons, Inc.  相似文献   

Quantitative estimation of skin soil moisture with the Special Sensor Microwave/Imager   总被引：1，自引：0，他引：1  

Koen De Ridder 《Boundary-Layer Meteorology》2000,96(3):421-432

A physically based retrieval scheme is described toinfer near surface moisture content of bare soilpatches from time series of the Special SensorMicrowave/Imager (SSM/I) Polarisation DifferenceTemperature (PDT) at 19.35 GHz. The PDT is modelled asa function of soil moisture using Fresnel's relationsfor specular reflection at the air-soil boundary,together with a dielectric mixing model for themoisture-dependent soil dielectric constant. Theproblem of the specification of parameters describingatmospheric and soil roughness effects is avoided byconsidering temporal variations of the PDT. Theretrieval method is applied to the FIFE site for atwo-week period in summer, during which heavy rainfalloccurred on a dry upper soil. Although differences insensing depths made a rigorous validation impossible,remotely sensed soil moisture showed a high degree ofconsistency with ground measurements. An erroranalysis shows that the method is capable of providingan accuracy of approximately 20% of moisture contentat field capacity. Finally, it is demonstrated thatthe method is relatively insensitive to soil texturalcharacteristics when moisture content is scaled withfield capacity.  相似文献   

Natural Hazards Monitoring:Forest Fires, Droughts And Floods - The Example Of European Pilot Projects   总被引：2，自引：0，他引：2  

J. San Miguel-Ayanz  J. Vogt  A. De Roo  G. Schmuck 《Surveys in Geophysics》2000,21(2-3):291-305

This paper reviews the subject of naturalhazards and the use of existing remote sensing systemsin the different phases of disaster management forsome specific natural hazards: forest fires, droughtsand floods. It centers on the applicability of remotesensing for increasing preparedness, providing earlywarnings, monitoring the hazards in real time, andassessing the damage so that relief can be provided. Comparison of the information provided by existingsystems and that needed for operational use of remotesensing in disaster management is also addressed. Thecapability of some of the future sensors to complywith the needs in the field of natural hazards isdiscussed. In this context current pilot projectscarried on at the European Commission Joint ResearchCentre are presented.  相似文献   

Super-silicic garnet microstructures from an orogenic garnet peridotite, evidence for an ultra-deep (>6 GPa) origin   总被引：1，自引：0，他引：1  

Van Roermund  Drury  Barnhoorn  & De Ronde 《Journal of Metamorphic Geology》2000,18(2):135-147.

We report the field, petrographic and mineral chemical characteristics of relict super‐silicic (=majoritic) garnet microstructures from the Otrøy peridotites in the Western Gneiss Region, Norway. The evidence for the former existence of super‐silicic garnet consists of two‐pyroxene exsolution microstructures from garnet. Estimates of the initial composition of the super‐silicic garnet imply pressures of 6–6.5 GPa, indicating that the Otrøy garnet peridotites were derived from depths >185 km. The garnet peridotites consist of inter‐banded variable compositions with c. 50% garnet peridotite and 50% garnet‐free peridotite. Two distinct garnet types were identified: (a) normal matrix garnet, grain‐size ≤4 mm, and (b) large isolated single garnet crystals and/or (polycrystalline) garnet nodules up to 10 cm in size. Large garnet nodules occur only within limited bands within the garnet peridotites. The relicts of super‐silicic garnet were exclusively found in some (not all) of the larger garnet nodules. Petrographic observations revealed that the microstructure of nodular garnet consists of the following four characteristic elements. (1) Individual garnet nodules are polycrystalline, with grain sizes of 2–8 mm. Garnet grain boundaries are straight with well‐defined triple junctions. (2) Some garnet triple junctions and garnet grain boundaries are decorated by interstitial orthopyroxene. (3) Cores of larger polycrystalline garnet contain two‐pyroxene exsolution microstructures. (4) Precipitation‐free rims (2 mm thick) surround garnet cores containing the exsolved pyroxene microstructure. Pyroxene exsolution from super‐silicic garnet was subsequently followed by brittle–ductile deformation of garnet. Both exsolved pyroxene needles and laths become undulous or truncated by fractures. Simultaneous garnet plasticity is indicated by the occurrence of high densities of naturally decorated dislocations. Transmission electron microscopy observations indicate that decoration is due to Ti‐oxide precipitation. Estimates of the P–T conditions for mineral chemical equilibration were obtained from geothermobarometry. The mineral compositions equilibrated at mantle conditions around 805±40 °C and 3.2±0.2 GPa. These P–T estimates correspond to cold continental lithosphere conditions at depths of around 105 km. From a combination of both depth estimates it can be concluded that the microstructural memory of the rock extends backwards to twice as great a depth range as obtained by thermobarometric methods. Available geochronological and geochemical data of Norwegian garnet peridotites suggest a multi‐stage, multi‐orogenic exhumation history.  相似文献   

沉积有机相在陆相层序地层格架中的分布特征--以吐哈盆地台北凹陷及准噶尔盆地南缘中侏罗世煤系为例   总被引：15，自引：1，他引：14  

杨建业  任德贻 《沉积学报》2000,18(4):585-589

综合应用有机岩石学、地球化学及孢粉学的研究方法,对吐哈盆地台北凹陷及准噶尔盆地南缘J2x煤系的沉积有机相在陆相层序的格架中的分布特征进行了探讨。研究表明,一般情况下,各类沉积有机相在层序地层格架纵向上以湖侵体系域为中心对称分布,生烃能力最强的烃源岩出自湖湾-半深湖有机相,其位置一般出现在湖侵体系域中部,向上向下,烃源岩生烃能力依次变差。  相似文献   

A detailed analysis of two seismic sequences in Abruzzo, Central Apennines, Italy     

G. De Luca  R. Scarpa  L. Filippi  A. Gorini  S. Marcucci  P. Marsan  G. Milana  E. Zambonelli 《Journal of Seismology》2000,4(1):1-21

A three-component digital seismic network has been installed along central Apennines since the end of 1991. Two seismic sequences having main shocks of magnitudes 3.9 and 3.7 were recorded in August 1992 and June 1994, respectively. A detailed analysis of these sequences, including multiplet relocation, fault-plane solutions and source parameter estimation, is performed in the present paper. A correlation analysis allowed us to recognize a number of correlated events in the two sequences which were used for relative locations using a master event technique. This analysis allowed to obtain a better alignment of epicentral data along two almost orthogonal directions, following an Apenninic and an anti-Apenninic trend. For the two sequences, fault-plane solutions were evaluated by using a first arrival technique, resulting in mechanisms with predominant normal faulting for the 1992 and 1994 swarms. S-wave polarization analysis allowed to check the stability of the previous solutions and to reduce their range of uncertainty. The same technique was also applied to derive the composite fault-plane solutions from the aftershocks, resulting in solutions which are in good agreement with those derived from the main shocks of both sequences. Source parameters were then derived from the three-component records of 28 well-recorded events with seismic moment in the range 8.5 × 10¹⁰–1.0 × 10¹⁴ Nm. Stress drops ranged in the interval 0.3–52.3 bar and source radii were of the order of 100 m. Their scaling relations are in good agreement with other results derived from the analysis of other Italian earthquakes that occurred in regions of predominantly normal faulting tectonics (Apennines and Calabrian arc).  相似文献   

Stream-scanning laser system, electric sensing counter and settling grain size analysis: a comparison using reference materials and marine sediments     

Emanuela Molinaroli  Giovanni De Falco  Sandro Rabitti  Rosana Asunta Portaro 《Sedimentary Geology》2000,130(3-4):269-281

Surface and deep-sea core sediments and two sets of standards were measured by three different techniques — Galai Cis-1 laser system, Coulter Counter TA II, and Micromeritics SediGraph 5000D — in order to compare the Galai results with the other two. The differences between the three types of measuring device turned out to be greater in sediments than in standards, and were attributed to the physical properties, shape, density and composition of the particles (complexity of the matrix). Comparison of moment statistics showed that the Galai determines coarser grain sizes than the Coulter and finer than the SediGraph, particularly as regards analysis of surface sediments. The relationships between Galai and SediGraph were estimated using analysis of variation/residuals within individual intervals. The analysis showed a higher variability of residuals for the coarser fractions (8–16 μm and 16–32 μm) with respect to the finer (2–4 μm and 4–8 μm) fractions. The <2 μm SediGraph fraction, with a cut-off at 0.49 μm, showed good correspondence with the <2.5 μm Galai analysis.  相似文献   

松辽盆地徐家围子断陷营城组火山岩相和火山机构分析   总被引：47，自引：0，他引：47  

陈建文  李长山 《地学前缘》2000,7(4):371-379

徐家围子断陷营城组火山岩极为发育。文章通过对火山岩的岩芯观察、薄片鉴定、岩芯测试及测井资料、二维、三维地震资料的综合分析 ,将营城组火山岩盆地分为 3大相区 ,即火山喷发区、过渡区和沉积区。火山喷发区岩性由各种熔岩、火山碎屑岩和少量砂砾岩组成 ;过渡区岩性以火山碎屑岩与沉积岩互层为特征 ,夹少量火山熔岩 ;沉积区岩性包括砂砾岩、砂岩、粉砂岩和泥岩。火山喷发区内可识别出 8种类型的火山岩相 (空落相、溢流相、基底涌流相、火山碎屑流相、火山泥石流相、火山沉积相、次火山相、隐爆角砾岩相 )和 3种类型的火山机构 (层火山、微型盾火山和渣锥火山 )。不同类型的火山机构具有不同火山作用、岩相分布特征和含油气性。因此火山岩相及火山机构分析对火山作用研究和油气勘探均有重要意义。  相似文献