1∶20万综合水文地质图分版刻绘工艺     

罗平书 《南方国土资源》1996,(3)

介绍了１∶２０万综合水文地质图分版刻绘工艺方案及技术特点，以及分版原则、分版内容及具体作业方案  相似文献   

Millennial‐scale precipitation changes over Central Africa during the late Quaternary and Holocene: evidence in sediments from the Gulf of Guinea     

Achakie C. Itambi  Tilo von Dobeneck  Adesina T. Adegbie 《第四纪科学杂志》2010,25(3):267-279

We combine environmental magnetism, geochemical measurements and colour reflectance to study two late Quaternary sediment cores: GeoB 4905‐4 at 2° 30′ N off Cameroon and GeoB 4906‐3 at 0° 44′ N off Gabon. This area is suitable for investigating precipitation changes over Central and West Africa because of its potential to record input of aeolian and fluvial sediments. Three magnetozones representing low and high degree of alteration of the primary rock magnetic signals were identified. The magnetic signature is dominated by fine‐grained magnetite, while residual haematite prevails in the reduced intervals, showing increase in concentration and fine grain size at wet intervals. Our records also show millennial‐scale changes in climate during the last glacial and interglacial cycles. At the northern location, the past 5.5 ka are marked by high‐frequency oscillations of Ti and colour reflectance, which suggests aeolian input and hence aridity. The southern location remains under the influence of the Intertropical Convergence Zone and thus did not register aeolian signals. The millennial‐scale climatic signals indicate that drier and/or colder conditions persisted during the late Holocene and are synchronous with the 900 a climatic cycles observed in Northern Hemisphere ice core records. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Optical and infrared photometry of new very low‐mass stars and brown dwarfs in the σ Orionis cluster     

V. J. S. Bjar  M. R. Zapatero Osorio  R. Rebolo 《Astronomische Nachrichten》2004,325(9):705-713

We present an RI photometric survey covering an area of 430 arcmin² around the multiple star σ Orionis. The observations were conducted with the 0.8 m IAC‐80 Telescope at the Teide Observatory. The survey limiting R and I magnitudes are 22.5 and 21, and completeness magnitudes 21 and 20, respectively. We have selected 53 candidates from the I vs. R–I colour‐magnitude diagram (I = 14–20) that follow the previously known photometric sequence of the cluster. Adopting an age of 2–4 Myr for the cluster, we find that these objects span a mass range from 0.35 M_⊙ to 0.015 M_⊙. We have performed J‐band photometry of 52 candidates and K_s photometry for 12 of them, with the result that 50 follow the expected infrared sequence for the cluster, thus confirming with great confidence that the majority of the candidates are bona fide members. JHK_s photometry from the Two Micron All Sky Survey (2MASS) is available for 50 of the candidates and are in good agreement with our data. Out of 48 candidates, which have photometric accuracies better than 0.1 mag in all bands, only three appear to show near‐infrared excesses. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

Dolphin noises recorded by echo‐sounder     

L. J. Paul 《新西兰海洋与淡水研究杂志》2013,47(2):343-348

The ultrasonic signals of dolphins show as “interference noise” on an echo‐sounder record. Some records obtained from Delphinus delphis in Hauraki Gulf, New Zealand, suggest that these emissions were being used for echo‐ranging, a phenomenon well established by previous work. Possible uses of such records in studying dolphin behaviour are explained.  相似文献   

水体石油类物质生物-光学遥感反演模型   总被引：2，自引：1，他引：1  

HUANG Miaofen  SONG Qingjun  XING Xufeng  ZHAO Zulong 《海洋学报(英文版)》2014,33(5):81-85

A biooptical modeling, which is based on a radiation transfer model, can be employed to simultaneously retrieve the concentration of various colour factors by multi-spectral remote sensing data, after connecting inherent optical properties （absorption coefficient and backward scattering coefficient） of colour factor with apparent optical properties （remote sensing reflectivity）. At present, this method has been used in a relatively wide range of applications in the inversion of a conventional water colour factor concentration in the case II water body： applications such as chlorophyll, suspended sediment, yellow substance. On the basis of extensive field testing data of water quality, correspondingly apparent optical properties, and the full use of the existing parametric model of colour factor inherent optical properties （with the parametrization of petroleum substance inherent optical properties established in the project） the remote recognition model for oil concentration is established by introducing oil as a new water co/our factor into a biooptical remote algorithm. The estimated value of the oil concentration was obtained by solving the biooptical model, using the data measured in May 2008 and August 2009 and June 2010 in seawater. The highly accurate inversion result promises to estimate the oil concentration in water for remote sensing.  相似文献   

Towards a Deeper Understanding of Cartographic Text Visualisation: Assessment of User Preferences and Colour Influence     

Rasha Deeb  Kristien Ooms  Veerle Van Eetvelde  Philippe De Maeyer 《The Cartographic journal》2013,50(4):325-335

The main goal of this research is to investigate the influence of a map’s background colour on user preferences regarding labels’ typography, including their size, shape, orientation and texture. Four sets of backgrounds were tested: blank maps, grey scale, hot colours and cold colours. The foreground of these maps is populated with name labels, which are associated with point objects or areal objects. Bertin’s visual variables were applied to this set of name labels, both separately and in combination. User preferences of different typographic variations were registered and compared on the basis of different background colours using a one-way ANOVA. The results indicated that the typographic design of the map labels should not be adapted according to the map’s background colour.  相似文献   

Maps > Representation     

Alexander J. Kent 《The Cartographic journal》2013,50(3):203-204

Abstract

Colour is considered a key means of expression for use in cartographic works. This is because colours and the relations among them influence not only the aesthetic impression a map creates but also its overall utility. In addition to Newton’s spectral colour theory, today theories with origins in artistic technique are gaining ground in cartography. This article introduces J. Itten’s colour theory (first published in 1961 in The Art of Colour [Kunst der Farbe]) with special attention given to his concept of seven colour contrasts. The article also discusses the suitability and unsuitability of their application in practical cartography, and it contributes original examples employing thematic maps, a discipline with broad possibilities for the application of these inventive methods by today’s mapmakers.  相似文献   

国外遥感技术在烃类微渗漏探测中的应用简介     

张磊 《国土资源遥感》1995,6(1):55-60

油气藏中的挥发组份通过上覆地层微裂隙渗漏到地表,形成烃类物质地球化学异常晕。遥感作为一门新技术,已有效地应用到地表油气微渗漏异常的探测。本文主要介绍国外在因烃类微渗漏而造成的油气田地表土壤变化、岩石蚀变和地植物异常等方面的研究现状,以及国外在探索其形成机制方面的进展,并介绍国外石油遥感专家利用各种遥感手段进行烃类微渗漏探测的有效方法,望能达到推动我国石油遥感研究进一步深入与发展的目的。  相似文献   

翡翠的化学成分和矿物组成特征   总被引：2，自引：0，他引：2  

唐俊  奥岩 《安徽地质》2000,(1)

对不同颜色的翡翠进行了较系统的化学成分和矿物成分研究，发现翡翠的化学成分和矿物 成分与翡翠的颜色之间有一定的内在规律。随着翡翠的绿色由浅变深，Ｃｒ、Ｍｇ、Ｃａ等元素的含量逐渐增 高，硬玉和绿辉石矿物成分逐渐向透辉石－钙铁辉石系列演化。  相似文献   

论地图符号中的地图美学     

刘川蔡畅  张景辉 《解放军测绘研究所学报》2007,27(4):25-28

地图产品是科学和艺术的结合体，地图符号又是表现地图艺术的重要载体，本文介绍了地图美学在地图信息传输巾的重要性和地图符号构成的地图美学要素，从地冈符号的形状、尺寸和色彩方面探讨地图美学应用的问题，提出了关丁符号设计方面的几点看法。  相似文献