Design And Research Of The Blind Electronic Map

With the increasing number and more attention of the visually impaired,the tools that help the visually impaired live,study and work are emerged.Tools include blind reading,blind phone,blind digital library on the Internet,and so on,which bright convenience and help for the blind.The blind have the same demands as the normal vision,who wants to communicate with the outside world and to understand the world.However,Vision impairment has brought great inconvenience to the lives of the blind,especially to their daily traveling.To solve problems of the visually impaired people,the key is to help them to understand geographic environment.The map is the carrier of geographic information,and is the important tool in helping people to understand geographic environment and to cognize geographic world.At present,there are scarce maps for the blind,and the most common blind map is touch map which by touching the map model to obtain spatial information and geographical things.However,there are some deficiencies in touch map,such as special materials,complicated production process and consuming time.Due to the deficiency the scope and content of the touch map is limited,and leads to less production.Map can't meet the demand of practical application.Due to the lack of blind map,the blind users always face harassment in special education Section.They are unable to learn geography and explore the external environment through the map.Therefore,it is of great social value and practical value to design an electronic map for the blind.This paper is based on the blind geospatial cognition model,the content of blind electronic map,schematization of road network,sonification of geographic information and the realization and application of blind electronic map to research and explore the blind electronic map,and finally generate the blind electronic map.The main content of this paper are as follows:(1)The blind's geospatial cognition model is established.Based on geo-perception,geo-mental imagery,geo-conceptualization,mental representation of geographic knowledge and geo-spatial reasoning,this study combined with the particularity of non-vision geospatial perception,to analysis and research the process of geo-spatial cognition for the blind.Based on this,the blind's geospatial cognition non-vision model is established,includes real world model,blind concept model,blind relationship model and blind spatial reference model.The design and research of the blind electronic map is based on the blind geospatial cognition model.(2)Concept of blind electronic map is proposed.Based on investigation and analysis on spatial cognition of blind people,the concept of blind electronic map is proposed,the characteristics of map are analyzed.This paper reaserches the content of the blind electronic map,and proposes the design principle and design flow of the map.(3)Using schematic road network as the basic road network data for the blind electronic map is proposed.The blind use map through the sense of hearing or touch,so as to road network data is too complex to use.Meanwhile manufacture and production of blind electronic map need to based on blind mental map,and the map is similar to mental map.As a result of the cognitive expression,mental map has its characteristic of imperfection,deformation,qualitative mode,abstraction and uncertainty.It emphasizes the topology that needed to be expressed and simulated by special graphic form.Schematic map exactly simulates mental map of road network in the memory and expresses topological structure of road network abstractly.Therefore,Schematic road network should be considered as the basic data of blind electronic map,and to provide abstract,concise,schematic road network data for the blind to understand and distinguish.(4)A schematic algorithm on the integration of stroke construction and displacement for road network is proposed,and a method for quantitatively assessing schematic algorithm is conducted.The existing schematic algorithms have disadvantages of cumbersome steps,time consuming,and multiple iterations.To resolve these problems,a schematic algorithm on the integration of stroke construction and displacement for road network is proposed.This algorithm ensures the uniformity of road target,and relieves the local focus problem which was brought by the grade division.The method is more effective,faster,easier in topology maintain than common algorithms.The method also can guarantee the road network connectivity and spatial cognition of schematic results.Besides,similar fractal dimension is presented to evaluate and analyze test result quantitatively,because the current schematic algorithm can only assess algorithm qualitatively.(5)A method of sonification for geographical information is proposed.Based on the content of the blind electronic map,this paper puts forward the use of the audible technology to realize the audible display of geographic information.The sonification mappings of category information,attribute information and geometric information are established,which is used to realize sonification of geographical information.The key to the realization of the blind electronic map is the sonification for the geographic information.(6)The auditory symbol system is established,and the blind electronic map is generated.Auditory symbol database is built,it can new,delete,query,update and export auditory symbol.Based on the auditory symbol system,human computer interaction for blind electronic map is achieved.Ultimately the blind electronic map is generated.