THE SPATIAL, STRUCTURE AND THE CHARACTERISTICS OF NODAL REGIONS WITHIN SEOUL

Abstract

This study examines the spatial structure of nodal regions at a microscopic scale and analyses the relationship between the pattern of the daily movement of persons and the regional characteristics within Seoul from the stand-points of socio-economic dimensions and trip purposes. A general field theory of spatial behavior is extensively applied for this study. The main results of this study can be summarized as follows: 1: Since the cartographic analysis, using the origin/destination data being constituted of the daily movement flows of persons by 123×123 districts, is impossible to reveal a distinct pattern of flows, the method of the largest flows is adapted to distinguish the major flow patterns and cluster analysis is used to delimit nodal regions. As the results, it is possible to identify that a closed pattern of flows is formed within one of the areas. The flows from outside of the city (zone number from 112 to 123 in Fig. 1) are generated or pulled within peripheral zone (Fig. 2). Meanwhile, interregional similarities of the movements are defined by correlation analysis. (Fig. 3). It suggests a neighbourhood influence at work in a system, whereby the greatest similarities are to be found between adjacent zones. This correlation analysis of each column or destination vector in the OD matrix is highly related to each other, yielding a 111 X 111 matrix of coefficient. The similarities of the central parts of Seoul are more significant than the periphery zones in particular, and also in proportion to the degree of urbanization. 2. In order to delimit the nodal regions, cluster analysis of origin zones after transformating from the OD matrix to correlation matrix is applied. By examining the loss of detail or similarity, the writer delimited 7 regions in the first stage but 17 regions in the second stage ; the regions are available at 0. 75 of similarity index, and the sub-regions are 0. 80. Boundary of the nodal regions correspond with natural obstacles (mountain or river) and administrative divisions (Gu boundary). The nodal regions and sub-regions are as follows (Fig. 4); Nodal region A……Central area (31 zones) Nodal region B……Dobong-Seongbug area (26 zones): sub-regions B1_??_B5 Nodal region C……Yeongdeungpo area (15 zones): sub-regions C1_??_C2 Nodal region D……Gangnam area (13 zones): sub-regions D1_??_D2 Nodal region E……Gwanag area (6 zones): sub-regions E1_??_E2 Nodal region F……Seodaemun area (15 zones): sub-regions F1_??_F3 Nodal region G……Cheonho area (5 zones): sub-regions G1_??_G2 Hierarchy of centers were ranked by grading of centers for all nodes having the largest flows. Thirty-eight centers were required by the method. It is remarkable that the intervals between the centers maintain regular spaces each other, and in the same time the intervals are different in accordance with the hierarchy of centers. But the hierarchy of nodal centers Because in Seoul, southern areas in particular, is not yet differentiated thoroughly (Fig. 4). nodalitY is identified as a behavioral act of man, it is not simply a geometric point or a intersect of traffic network. 3. Subsequently, the relationship between the nodal regions and urban structural characteristics or different purpose trips are summarized as follows: In order to analyse the regional characteristics of Seoul, 30 variables were recognized by factor analysis and 6 different types of trips were identified by Nelson's classification method. By comparing both, it was possible to estimate relationships between spatial behavior resulted from the character of places and spatial interactions resulted from the character of places in Seoul.