Decoding urban kernel in Japanese port cities by means of space syntax

Spatial rationality revealed by mathematical analyses seems less important in Japanese urban planning. In the case of Japanese provincial cities, the urban area of them has been expanded rapidly in this 50 year; therefore, the area around railway station is not the centre of efficiency anymore after the urban expansion. However, conventional residents still believe that the centre locates in front of the station. Such image of centrality might have already been forgotten by young people who have no experience of those days when the area was crowded. Nevertheless, this partiality seems to have been penetrating deeper to Japanese society, and not overcome yet. Now, this research attempts to address this problem from different angle rather than relegating it to a mere irrational concept. We have called this persisting residents’ perception the 'urban kernel'. The purpose of this study is to investigate the urban kernel by means of new concept and find spatial rationality from them. We will reveal the spatial structure which cannot be explained solely by the conventional concept of Global and Local, but by combining a new indicator. An index called D-Local is a measure that is based on the idea of clusters indicated by Local. By using D-Local, we will be able to find a clue for solving ‘boundary problem’ in Global. This new approach enables us to investigate Japanese port towns of which the configuration has been influenced by multiple conditions such as waterfront geographic context, immigrants, navy bases and so on, contributing to the understanding of the complexity in Japanese modern cities.