Real World Map Reading Strategies

Abstract

A main component of an Intelligent Transport System (ITS) is the navigation system to be used in the 'intelligent' vehicle. In fact, driving a vehicle is a complex task as the driver has to control the vehicle as well as make decisions about getting to his/her destination. Too much information on the map (i.e. a complex map) would confuse the driver, while too little information would not be sufficient for the user to compare with the actual environment. Sufficient information but poorly presented would also result in confusion.

This paper reports on a study of the design of dynamic maps for land vehicle navigation through an investigation of different designs with different levels of information contents and visual effects using various dynamic variables. Different colours were assigned to the road and building names according to the position of the vehicle, and blinking symbols were used to indicate direction restrictions. Also, a set of maps with different degrees of complexity was designed such that the users would be provided with different levels of contents and representation by zooming in and out. The effectiveness of the design was investigated in the map evaluation process.     

Continuity markers as an aid for children in finding the peripheral continuity of world maps

ABSTRACT

Many map readers, including both children and adults, find it difficult to determine where they would be located along the edge of a world map after crossing that edge. Different types of markers have long been drawn close to the map’s edge – for example, in an atlas – to help map readers identify the map upon which they will find themselves if that edge is passed. In this study, a method similar to that used to show the continuity between maps in an atlas has been tested to determine whether continuity markers can also be used to help map readers find a world map’s actual peripheral continuity. The study involved children between the ages of 10 and 13 years and showed that continuity markers do help children determine the map’s actual peripheral continuity, in combination with a lesson that describes how to find the actual peripheral continuity of a world map. This article, therefore, concludes that continuity markers for world maps can be a useful part of map design that clarifies how the edges of a world map fit together for children who have learned to use this tool.     

THE SCALE ERRORS OF AIRY'S PROJECTION BY BALANCE OF ERRORS,WITH SPECIAL REFERENCE TO THE BRITISH ISLES

Abstract

THE formula for the projection is based upon the spherical assumption. To calculate it for the spheroid might be very complicated and would not be worth while. The projection is suitable for very large areas as a compromise between the Zenithal Equal-area projection on the one hand and the Zenithal Equidistant or Zenithal Orthomorphic on the other. Its application to an area as small as the British Isles would not serve any useful purpose. An analysis of its errors in the general case reveals some unexpected simplicities. This analysis is given below, followed by its application to the particular case of the British Isles on the ten-mile scale. This is done merely to find out what changes would have occurred if the supposed drawing of that map on Airy's projection had been real.     

Recent Literature - Bookcase

Abstract

Why should a specialist sport require a map of its own? Trout fishing is not dependent on map use, but a carefully researched and presented map is a useful addition to the angler's tackle bag. The sport does not require the absolute planimetric accuracy of, say, an orienteering map, but careful research and selection of features is just as important. What information is essential to the angler and what is helpful? What is background information; and what, if anything, should be left off?     

Opening the London Underground to visually handicapped tourists

Abstract

There are several practical rules for determining categories (class intervals) for maps representing statistical data, like arithmetic, geometric or equal steps etc. In this paper, however a coherent method is proposed to provide statistically separable Classes on a map with minimum redundancy in terms of information content.

The number of class intervals can be directly computed by means of appropriate statistical methods if the widths of classes are determined by t-test, i.e. when their difference is significant at a high level of confidence. A class narrower than this width would represent data in different categories due only to variance, however, the selection of wider classes leads to a certain loss of information.

The class intervals determined this way should be positioned on the statistical data-set so that each category contains approximately equal number of data providing maximum information content of the output map. At the final step the class intervals derived this way should be rounded, if necessary, to provide user-friendly maps.     

Development of GIS-based environmental information system: an Indian scenario

Abstract

Ideally, scientists should be able to format, explore, analyse, and visualise data in a simple, powerful and fast application that would seamlessly integrate georeferenced data from a variety of data sources into an intuitive visualisation. The focus of an Environmental Information System is providing environmental information to decision makers, policy planners, scientists and engineers, research workers, etc. which ensures integration of data collection, collation, storage, retrieval and dissemination to all concerned. All such queries should be responded to supplying substantive information in the form of reports. The paper presents an innovative way to utilise the geographic information associated with the environmental data. The stand-alone application is the integration of using ArcObjects Environmental System Research Institute ArcGIS Engine 9.1 and VB.Net. The geographic information system (GIS)-based application, a framework of digital earth in terms of environmental information system provides a user-friendly query interface, which gives information about various environmental parameters in tabular as well as on map display. It also provides the visual interpretation to make further analysis and future decisions at multiple scales, locations and extents. The facility for modifying the map attributes and corresponding databases is integrated to update the information system. Output spatial data are produced in the form of reports using selected fields with display on map.     

Recent Literature - Bookcase

Abstract

A map has long been considered to be a legitimate communication medium, made by the cartographer for different map users. Valuable contributions to the scientific fundamentals of cartography should be expected from the critical investigation of communication aspects of the map, particularly map signs. This article first attempts to analyse the signs used in cartographic communication from the point of view of semiotics - especially semantics - then redefines the map, our communication tool, under its ascertained characteristics.     

EXPANSION OF PAPER AS AFFECTING BEARING

Abstract

In the last issue of this Quarterly the commonplace statement was repeated that coming of age brought its own troubles. One trouble, however, was forgotten: the tendency of the increasing age to devote itself to swords and spears rather than ploughshares and pruning hooks. While the peaceful partisans of the plough would look to maps to show the true acreage of their lands, the heavers of the hurtling bolt prefer a map which facilitates their deadly aims. How does expansion of paper affect the sights of those who would steal the thunder of Zeus?     

A bevy of area-preserving transforms for map projection designers

ABSTRACT

Sometimes map projection designers need to create equal-area projections to best fill the projections’ purposes. However, unlike for conformal projections, few transformations have been described that can be applied to equal-area projections to develop new equal-area projections. Here, I survey area-preserving transformations, giving examples of their applications and proposing an efficient way of deploying an equal-area system for raster-based Web mapping. Together, these transformations provide a toolbox for the map projection designer working in the area-preserving domain.     

Representing of contour lines by turning point preserving quadratic splines

Abstract

Terrain data obtained from satellite imagery or by scanning existing contour maps is in raster mode. Such data may be compressed by detecting and storing the critical points of contour lines. When hand digitising a contour map, a trained digitiser operator would usually select points which visually appear to be critical points. Existing interpolation techniques often fail to restore the critical points, including turning points, to their original positions. This article illustrates the use of splines composed of quadratic Bézier curves with monotone curvature for rendering contour lines which are represented only by their turning and end points, such that the positions of the turning points are preserved.     

TEMPERATURE ERRORS IN PRECISE TRAVERSING

Abstract

It is assumed that a precise traverse would be used only where triangulation would be impracticable, that an absolute accuracy of I in 100,000 would be required, and that reasonable speed would be necessary.     

THE YEAR 1931 IN NORTHERN RHODESIA

Abstract

In the survey world of Northern Rhodesia the most notable event in 1931 (apart, of course, from the birth of this Review) has been the completion of the aerial survey contracts undertaken for the Government by the Aircraft Operating Company. The results have justified expectations particularly with regard to the mapping of 63,000 square miles of the Territory on a scale of 1/250,000. Used in conjunction with the information obtained by ground methods by the Mining Companies, who have kindly consented to put their information at our disposal, a really reliable detailed map of a considerable portion of the Territory should be obtained. The mosaics of the six principal townships are also proving of value and contain a wealth of detail which would be difficult to obtain so accurately by ground survey except at great expense. On the other hand it is obvious that it would be a costly business involving a very large amount of ground control to prepare a closely contoured plan such as is required for detail purposes in connection with township lay-outs.     

Searching for the ‘Right’ Legend: The Impact of Legend Position on Legend Decoding in a Cartographic Memory Task

ABSTRACT

Map legends are key elements of thematic maps and cartographic communication. The question of how to style map legends is a topic which has often been addressed by cartographic academics and practitioners. Nevertheless, the question of where to position a map legend has only hardly been discussed. Principles of cognitive sciences allow the assumption that a legend positioned to the right of a map field can be read and decoded faster than a legend on the left side. This study investigates the impact of legend positioning on legend decoding. It involves an experiment based on a recognition memory paradigm and the registration of eye-movements. The results show that, in less time, a legend positioned to the right of the map field (compared to a left legend) can be decoded faster. The same accuracy of a cognitive representation of geographic space can be achieved in spatial memory.     

THE CADASTRAL MAP

Abstract

In the Empire Survey Review for April 1934 (No. 12, pp. 382–4), the Editor has raised the question of the function of the cadastral map. As he remarks, the question is not simple, but it is easier to say what the function of the map is than to decide of what the map should consist in order that it may fulfil its function. Broadly speaking we may state that the function of the map is to record the boundaries of landed property in such a manner as not only to afford a pictorial representation but also to supply data for the identification of these boundaries on the ground when occasion requires. Apart from this the map should show the areas of properties, as this information may be required for taxation purposes.     

Assessment of surface and subsurface waterlogging,water level fluctuations,and lithological variations for evaluating groundwater resources in Ganga Plains

Abstract

In the present study, the multi-temporal satellite images of IRS P6 LISS III were used to map waterlogging dynamics over different seasons. An area of 594.36 km² (6.75%) and 4.17 km² (0.04%) was affected by surface waterlogging during pre and postmonsoon season, respectively. The average annual groundwater level fluctuations were calculated using 18 years (1990–2007) pre and postmonsoon groundwater level data to identify the areas which are under groundwater induced waterlogging conditions. The soil map clearly indicates that salinity and sodicity exhibit the highest severity and occur in areas with shallow groundwater levels. The hydrogeomorphical units mapped using IRS P6 LISS III satellite images are flood plain, alluvial plain, paleochannels, and oxbow lakes. The study revealed that 44.65% areas have very good to excellent groundwater resources. The litholog data clearly indicate an alternating sequence of clay and sand in which deep aquifers made up of coarse sand would be best suited for adequate water supply and good groundwater quality. The integrated study utilizing digital spatial data pertaining to waterlogging, soil salinity, water level fluctuation, and lithological variation proved that planning of any surface and subsurface water resources development activity should be taken up after assessments of said parameters.     

'Be Map Aware: Cutting-edge…Not Close to the Edge'

Abstract

An assessment is made of the accuracy of the map and written survey, which is essentially a list of land-holders and the areas held by each, and of their mutual consistency. The geometry of the map is compared quantitatively with that of the first edition (1852) Ordnance Survey 6-inch (1 : 10 560) map. The Saxton map is found to have a scale of 1 : 5140, leading to the conclusion that the perch used in the scale bar represents 7¹/₉ yards or thereabouts. The areas quoted in the written survey are consistent with acres based on this value. The positional accuracy of points on the map is found to be ～20 m, and areas of typical plots determined from the map are uncertain by between about 4 and 12%. The relationship between these two facts can be understood through a detailed study of the statistics of the errors in separations of points on the map. The written survey is found to omit a substantial number of plots of land from its listings. The map thus appears to be more reliable overall than the written survey.     

Bartholomew and the Half-Inch Layer Coloured Map 1883–1903

Abstract

In their pre-war heyday Batholomew, that most famous of British commercial mapmakers, had a huge worldwide business in every sort and scale of map and atlas for every purpose; not to mention, at one time, an extensive general printing trade. But, even so, their name became firmly associated in the public consciousness with one particular design of map on one particular scale — the half-inch to one mile (1.126 720) layer colored map of Great Britain. This study deals with the early history of the phenomenon, in the context of the firm's other work. It concludes with the completion of the England and Wales series, and the moment when it could be said, in the most elevated and objective of contexts, that the British map buyer — trade and public both — had, thanks to this map, acquired 'the Bartholomew habit'.