This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is no...This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is not possible to read a local linear scale factor in the direction of a coordinate axis immediately from the definition of a local linear scale factor,this paper considers the derivation of new formulae that enable local linear scale factors in the direction of coordinate x and y axes to be calculated.The formula for computing the local linear scale factor in any direction defined by dx and dy is also derived.Furthermore,the position and magnitude of the extreme values of the local linear scale factor are considered and new formulas derived.展开更多
The problem of spatial mathematical basis has been encountered by both large scale GIS and spatial digital products theoretically and practically.It is also a basic problem in the development of the whole geo_informat...The problem of spatial mathematical basis has been encountered by both large scale GIS and spatial digital products theoretically and practically.It is also a basic problem in the development of the whole geo_information science.After analyzing the status quo and the limitations of the space mathematical base of GIS,this paper points out definitely that the geodetic coordinate system is uniform,which can show the location of any point of the global exactly and uniquely in form of ( B,L,H ) and is the most proper reference system of large_scale GIS and Digital Earth.Moreover,this paper also puts forward a set of practical model of the standard "map projection".Finally,this paper introduces a DRG system based on this model.展开更多
The third edition of the Geological Map of the World follows thefirst and second editions published by the CGMW respectively in1990 and 2000.This bilingual document(English-French)is the resultof a highly synthetic co...The third edition of the Geological Map of the World follows thefirst and second editions published by the CGMW respectively in1990 and 2000.This bilingual document(English-French)is the resultof a highly synthetic compilation given both the small scale of themap and its educational purpose.It is a tentative and(very)simplifiedrepresentation of the entire solid surface of our planet and includesboth continental and oceanic domains.This new edition is a completely revised concept compared tothe map issued in 2000 and takes into account the state of the geologicknowledge at the turn of the century.For the first time,the Map isdesigned in two sheets of the same size:Sheet 1(Physiography,Volcanoes,Astroblemes)revealingthe fine-grained texture of the totality of the Earth surface whenremoving the water of the oceans.展开更多
文摘This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is not possible to read a local linear scale factor in the direction of a coordinate axis immediately from the definition of a local linear scale factor,this paper considers the derivation of new formulae that enable local linear scale factors in the direction of coordinate x and y axes to be calculated.The formula for computing the local linear scale factor in any direction defined by dx and dy is also derived.Furthermore,the position and magnitude of the extreme values of the local linear scale factor are considered and new formulas derived.
文摘The problem of spatial mathematical basis has been encountered by both large scale GIS and spatial digital products theoretically and practically.It is also a basic problem in the development of the whole geo_information science.After analyzing the status quo and the limitations of the space mathematical base of GIS,this paper points out definitely that the geodetic coordinate system is uniform,which can show the location of any point of the global exactly and uniquely in form of ( B,L,H ) and is the most proper reference system of large_scale GIS and Digital Earth.Moreover,this paper also puts forward a set of practical model of the standard "map projection".Finally,this paper introduces a DRG system based on this model.
文摘The third edition of the Geological Map of the World follows thefirst and second editions published by the CGMW respectively in1990 and 2000.This bilingual document(English-French)is the resultof a highly synthetic compilation given both the small scale of themap and its educational purpose.It is a tentative and(very)simplifiedrepresentation of the entire solid surface of our planet and includesboth continental and oceanic domains.This new edition is a completely revised concept compared tothe map issued in 2000 and takes into account the state of the geologicknowledge at the turn of the century.For the first time,the Map isdesigned in two sheets of the same size:Sheet 1(Physiography,Volcanoes,Astroblemes)revealingthe fine-grained texture of the totality of the Earth surface whenremoving the water of the oceans.
