The purpose of this paper is to suggest the analysis methodology of map color scheme for the color vision impaired in the objective and quantitative ways. We tried to help solving problems related in using uneven color space and gamut indicated in existing studies. Consequently, we suggested the color-difference measurement method using CIELAB color system for the uniform color space and sRGB color gamut for setting the standard color space. Also, we set minimum color-difference standards for the color vision impaired to prevent misunderstanding color schemes on maps. We analyzed the variation of minimum color-difference before and after the simulation of color vision impairment and recommended safe color schemes for them. The proposed color-difference measurement method with the simulation tool of color vision impairment developed in our previous study can contribute to the recommendation of map color schemes depending on the characteristics of each color vision deficiencies.
Although numerous thematic maps are generated using GIS software, it is not apparent that these thematic maps properly provide the exact information which can be induced in the maps. This paper aims to show the guide line of legends of thematic maps for providing exact information. According to the thematic map types, some problems of thematic maps generation using ArcGIS are examined. The significant things which map maker should know are understandings of data and suitability of generated maps. In formal aspects, thematic maps generated using GIS software need editing procedures for the completeness of the thematic maps.
Functional regionalization using commuting data is a significant task in identifying the structure of urban areas. However, conventional methods, especially Intramax, are inadequate in optimizing functional connections between spatial units. Therefore, this paper aims to introduce alternative methods in delineating the commuting zones by incorporating an improved measurement for increasing internal flows and spatial components such as contiguity constraint and area balance constraint. Alternative algorithms are applied to the Seoul Metropolitan Area (SMA) to identify functional regions. Different functional zones generated by alternative methods are evaluated by the comparative assessment of the effects of the improved measurement and the spatial components. As a result, the new methods outperform the scores of the proportion of internal flows from Intramax, and the commuting zones generated through new methods are geographically reasonable across SMA.
This paper introduces an approach for analyzing multivariate spatial cluster/outlier in local scale. Even though spatial cluster/outlier has various definitions, the fundamental of spatial cluster/outlier is based on spatial association. Existing methods for measuring local spatial association had a limitation of applying multiple numbers of variables. Univariate local spatial association measures such as local Moran’s Ii, local Geary’s Ci and Getis and Ord’s Gi * are widely used, and bivariate local spatial association measures are already developed; Cross Moran and Lee’s Li. However, the measures are not used for measuring spatial association among three or more variables.
This is a critical limitation when spatial variation with the complex multi-dimensional approaches is explained and described. The measure in this paper, multivariate local spatial association measure, is based on Mahalanobis Distance (MD) and it enables distinguishing spatial similarities and differences among multiple numbers of data sets simultaneously. MD considers variables’ means, variances and co-variances and allows measuring the variables’distribution. It is the same concept as distance measuring with Euclidean Distance but improved. Significance of MD could be tested because it is following chi-square distribution when the variables are multi-normal. Local MD is applied to demographic variables, in- and out-migration in Seoul Metropolitan Area. The spatial variation of multivariables could be identified by chi-squared p-value map, and a local MD map is provided to show the detected spatial clusters or outliers at a given significance level.
As demand for wireless internet access or mobile services increases recently, universities are attempting to establish a mobile campus. Although the focus of building a mobile campus is on a Wi-Fi technology among wireless local area network(WLAN) products and AP(access point), a lack of systematic spatial planning may result in a highly densed distribution of APs for a particular area, and rather it causes a failure of internet access or inefficiency of communication. Also, the limited service coverage of a Wi-Fi service might cause many technical and economical difficulties in building an actual ubiquitous campus. In this regard, this paper analyzes the characteristics of current wireless infrastructure and service coverage, focusing on Chonnam National University’s main campus where the WLAN facilities were recently extended more. Further, we suggested optimal solutions for locating APs so that the sited APs cover all the dead Wi-Fi zones with the least cost. It is expected that the analytical results of this research would provide a useful guideline for many universities which seek to establish a Wi-Fi based U-campus.
The development of internet and transportation, and the expansion of global finance and culture have increased migrants in the world. In case of Korea, the changes of industrial structure, the changes of social values and the globalization of education have brought a sharp increase of foreign migrants. Recent migration study tends to giving attention on the spatial scale by migrant's social relations. Migrants are not only trying to maintain the transnational social relations, but also embedding into the local's socio-cultural environment, deriving local changes. This research attempted to reveal the characteristics of migrant space with diverse of scale levels through categories of states and visa-type in the city-gun-gu scale in national level and dong scale in Seoul. This research clearly shows the fact that migrant's residential spaces are different by nationality and migration status. Migrants tend to utilize a certain kind of social capital, making the new space of migrant. Routine labor migrants, mainly from asian countries, are concentrated on the manufacturing areas, while professional labor migrants from European countries such as U.S.A., U.K. France, Germany, and Australia are inclined to settle in the Yongsan area. Also There are several distinctive spatial distribution related to migration status (visa-type). Educational migrants tend to find their residential place nearby their ethnical anchorage. Marriage migrants who are dominated by female are highly concentrated into the city areas which are nearby the place of Korean-chinese's residential areas and the manufacturing areas. This research clearly shows that the space of migrants is different by nationality and migration status. Thus, the homogenisation of migrants by ethnic or state tend to raise a problem in migration studies.