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871.
在地质勘探现场工作中经常会遇到地理坐标和投影坐标转换的问题。本文通过对地理坐标和投影坐标原理的简要分析,根据高斯一克吕格投影平面下投影坐标转换成地理坐标的高斯反算公式,分析算法原理、设计算法流程,编制程序,并用MAPGIS软件进行比对分析,发现该程序能较好、有效地满足实际应用需求。 相似文献
872.
MAPGIS是在地质行业,尤其是在地质图的制作过程中被广泛应用的一种地理信息系统,利用MAPGIS软件制作一张复杂的地质图,其地层颜色的修改和属性的填写是极其繁琐的过程。通过利用点图元、面图元的注释、属性和参数间的关系可以很方便的添写地层颜色,利用投影参数将图元的地理坐标信息方便的挂接为图元的属性,可达到事半功倍的效果。 相似文献
873.
874.
Sebastian Orihuela 《The Cartographic journal》2013,50(2):158-165
The Lagrange projection represents conformally the terrestrial globe within a circle. This is achieved by compressing the latitude and longitude and by applying the new coordinates into the equatorial stereographic projection. The same concept can be generalized to any conformal projection, although the application of this technique to other analytical functions is less known. In this work, the general Lambert–Lagrange projection formula is proposed and the application of the modified coordinates is discussed on projections: stereographic, conformal conic and Gauss–Schreiber. In general, the results are merely a curiosity, except for the case of Gauss–Schreiber, where the use of coordinates with altered scale can be applied in the optimization of conformal projections. 相似文献
875.
Maxim V. Nyrtsov Maria E. Fleis Michael M. Borisov Philip J. Stooke 《The Cartographic journal》2013,50(2):114-124
Many small solar system bodies such as asteroids or small satellites have irregular shapes, often approximated by the reference surface of a triaxial ellipsoid. Map projections for the triaxial ellipsoid are needed to present the incoming data in the form of maps. In this paper the formulae of equal-area cylindrical and azimuthal projections of the triaxial ellipsoid were derived and practically implemented for the first time using as an example the asteroid 253 Mathilde. This paper is the final in a series of papers devoted to all main classes of projections of the triaxial ellipsoid. Before this, the authors obtained equidistant along meridians projection and Jacobi conformal projection for the triaxial ellipsoid. 相似文献
876.
877.
2013年4月20日四川芦山发生7.0级地震.本文运用反投影远震P波的方法研究了中心频率为1 Hz的芦山地震震源破裂特征.研究结果显示2013年芦山7.0级地震破裂长度约为20 km,震源破裂时间约为26 s.本文认为在芦山地震的开始阶段(0~4 s)震源的破裂是向震中位置两侧进行的.而芦山地震破裂的第二阶段(5~26 s)是单侧破裂.芦山地震最大能量释放区域位于震中以北.本文对比了运用相同方法研究的发生在同一断裂带上的2008年汶川地震震源破裂特征.发现2013年芦山地震和2008年汶川地震有三点相似之处,即,破裂主要沿北东走向的龙门山断裂带发展;最大能量释放区域没有位于震中;能量都是通过多次子事件来释放的,且第二次能量释放是最大能量释放.对比两次地震破裂区域,可以看出芦山地震的破裂区域是在2008年汶川地震破裂区域的西南端发展的.两次地震的破裂区域占了整个龙门山断裂带的三分之二. 相似文献
878.
《The Professional geographer》2013,65(4):487-488
Book Reviewed in this article: Geographical Aspects of Health and Disease in India. Rais Akhtarand A.T.A. Learmonth, eds. Antarctic Treaty System: An Assessment. Proceedings of a Workshop at Beardmore South Field Camp, Antarctica. American Electoral Mosaics. J. Clark Archerand Fred M. Shelley. Kompas op Suidwes-Afrika/Namibie. W.S. Barnard, ed. Jerusalem in the 19th Century: The Old City. Yehoshua Ben-Arieh. The World as a Total System. Kenneth E. Boulding. A Social History of Housing 1815–1985, Second Ed. John Burnett. Human Migration. W.A.V. Clark. Regional Population Projection Models. Andrei Rogers. The State of Population Theory: Forward from Malthus. David Colemanand Roger Schofield, eds. Imagining Tomorrow: History, Technology and the American Future. Joseph C. Corn, ed. Swidden Agriculture in Indonesia: The Subsistence Strategies of the Kalimantan Kantú. Michael R. Dove. Glacial Geologic Processes. David Drewry. Physics of Desertification. Farouk El-Bazand M.H.A. Hassan, eds. Housing the Homeless. Jon Ericksonand Charles Wilhelm, eds. Settlement Patterns in Missouri: A Study of Population Origins, with a Wall Map. Russel L. Gerlach. Desert Development: Man and Technology in Sparselands. Yehuda Gradus, ed. Nuclear Winter. The Evidence and Risks. Owen Greene, Ian Percivaland Irene Ridge. The Take-off of Suburbia and the Crisis of the Central City. Günter Heinritzand Elisabeth Lichtenberger, eds. Regional Input-Output Analysis. Geoffrey J. D. Hewings. Spatial Transportation Modeling. Christian Werner. The Atlas of Georgia. Thomas W. Hodlerand Howard A. Schretter, eds. Latin America. 5th ed. Preston E. Jamesand C.W. Minkel. Applied Remote Sensing. C.P. Lo. Localities, Class, and Gender. The Lancaster Regionalism Group. Urban Social Movements: The City after Castells. Stuart Lowe. Politics and Method. Doreen Masseyand Richard Meegan, eds. Land Use. A. S. Mather. The Kingdom of Coal. Donald L. Millerand Richard E. Sharpless. The Presidio and Militia on the Northern Frontier of New Spain, A Documentary History, Vol. 1: 1570–1700. Thomas H. Naylorand Charles W. Polzer, S.J., comps. andeds. Nuclear Power: Siting and Safety. Stan Openshaw. The Central African Republic: The Continent's Hidden Heart. Thomas O'Toole. Environmental and Dynamic Geomorphology. Márton Pécsi, ed. Remote Sensing Principles and Interpretation. Floyd F. Sabins, Jr. Acid Rain and Friendly Neighbors: The Policy Dispute between Canada and the United States. Jurgen Schmandtand Hilliard Roderick, eds. Earth's Changing Surface: An Introduction to Geomorphology. M.J. Selby. International Migration: The Female Experience. Rita J. Simonand Caroline B. Brettell, eds. On Geography and Its History. D.R. Stoddart. Transportation Networks: A Quantitative Approach. D. Teodorovic. Processes in Physical Geography. R.D. Thompson, A.M. Mannion, C.W. Mitchell, M. Parry, J.R.G. Townshend. Imaging Radar for Resources Surveys. J.W. Trevett. Dominance and Affection: The Making of Pets. Yi-Fu Tuan. Capturing the Horizon. The Historical Geography of Transportation since the Transportation Revolution of the Sixteenth Century. James E. Vance, Jr. Nations at Risk: The Impact of the Computer Revolution. Edward Yourdon. 相似文献
879.
Bernhard Jenny Tom Patterson Lorenz Hurni 《International journal of geographical information science》2013,27(11):1687-1702
The design of new map projections has up until now required mathematical and cartographic expertise that has limited this activity to a small group of specialists. This article introduces the background mathematics for a software-based method that enables cartographers to easily design new small-scale world map projections. The software is usable even by those without mathematical expertise. A new projection is designed interactively in an iterative process that allows the designer to graphically and numerically assess the graticule, the representation of the continents, and the distortion properties of the new projection. The method has been implemented in Flex Projector, a free and open-source application enabling users to quickly create new map projections and modify existing projections. We also introduce new tools that help evaluate the distortion properties of projections, namely a configurable acceptance index to assess areal and angular distortion, a derived acceptance visualization, and interactive profiles through the distortion space of a projection. To illustrate the proposed method, a new projection, the Cropped Ginzburg VIII projection, is presented. 相似文献
880.
赋偏序向量空间的格子空间指的是它的一个向量子空间对于诱导序(the induced ordering)成为一个Riesz空间。主要研究了正则算子空间上的一类格子空间,其中每一个正则算子的值域具备Dedekind完备性。首先讨论了一类经典Riesz空间上的正投影,然后得到主要结果存在Riesz空间上的一类正投影使它的值域成为一格子空间,最后讨论了全空间与格子空间中正则算子的不交性。 相似文献