Keiji Yano

Visualising Crime Clusters in a Space-time Cube: An Exploratory Data-analysis Approach Using Space-time Kernel Density Estimation and Scan Statistics

For an effective interpretation of spatio-temporal patterns of crime clusters/hotspots, we explore the possibility of three-dimensional mapping of crime events in a space-time cube with the aid of space-time variants of kernel density estimation and scan statistics. Using the crime occurrence dataset of snatch-and-run offences in Kyoto City from 2003 to 2004, we confirm that the proposed methodology enables simultaneous visualisation of the geographical extent and duration of crime clusters, by which stable and transient space-time crime clusters can be intuitively differentiated. Also, the combined use of the two statistical techniques revealed temporal inter-cluster associations showing that transient clusters alternatively appeared in a pair of hotspot regions, suggesting a new type of “displacement” phenomenon of crime. Highlighting the complementary aspects of the two space-time statistical approaches, we conclude that combining these approaches in a space-time cube display is particularly valuable for a spatio-temporal exploratory data analysis of clusters to extract new knowledge of crime epidemiology from a data set of space-time crime events.

Combining microsimulation and spatial interaction models for retail location analysis

Although the disaggregation of consumers is crucial in understanding the fragmented markets that are dominant in many developed countries, it is not always straightforward to carry out such disaggregation within conventional retail modelling frameworks due to the limitations of data. In particular, consumer grouping based on sampled data is not assured to link with the other statistics that are vital in estimating sampling biases and missing variables in the sampling survey. To overcome this difficulty, we propose a useful combination of spatial interaction modelling and microsimulation approaches for the reliable estimation of retail interactions based on a sample survey of consumer behaviour being linked with other areal statistics. We demonstrate this approach by building an operational retail interaction model to estimate expenditure flows from households to retail stores in a local city in Japan, Kusatsu City.

Virtual city models for assessing environmental equity of access to sunlight: a case study of Kyoto, Japan

Virtual city modelling is expected to play a central future role in the field of urban planning and design. Currently, most of the uses of this modelling method are related to the production of visualizations, but there is also a potential for developing novel methods of spatial analysis that focuses on vertical variations in, for example, building heights. One application concerns the assessment of access to sunlight. This is an essential consideration in urban planning, and there is considerable demand for geographical information systems which can provide efficient solar radiation analyses. Nevertheless, few studies have attempted to model variations in sunlight exposure over entire urban areas. This article illustrates an application of solar radiation analysis using a detailed virtual urban modelling for the case study of city of Kyoto, Japan. The research presents and implements a methodology to examine how sunlight access varies between different social groups in the city. The findings, which show evidence of inequity, illustrate the potential of virtual city models and their benefits are discussed along with the caveats of their application.

The use of a virtual city model for assessing equity in access to views

The development of virtual city models has provided novel possibilities for analyses that require consideration of building heights in urban areas. The study was undertaken to explore these possibilities by using the virtual Kyoto model to examine equity in access to views in the Japanese city. A sample of just over 5000 residences was selected by stratifying for population age and affluence. A series of viewsheds were computed to quantify the visibility of a range of environmental amenities (greenspaces, water bodies, historical buildings, mountains) and disamenities (factories and roads). Evidence of inequity in visual amenity was identified, whereby homes in areas with many old people were much less likely to have views of greenspaces and water bodies, although they were also less likely to see factories and roads and were more likely to view mountains. Homes in more affluent areas had better views of greenspaces, historical buildings, and mountains, and were less likely to see factories and water bodies. We discuss the potential of virtual city models for furthering analyses of the urban environment and raise some caveats regarding their use.

Reconstruction of Kyoto of the Edo era based on arts and historical documents: 3D urban model based on historical GIS data

This paper explores a method for creating large-scale urban 3D models using Historical GIS data. The method is capable of automatically generating realistic VR models based on GIS data at a low cost. 3D models of houses are created from polygon data, fences from line data, and pedestrians and trees from point data. The method is applied to the Virtual Kyoto Project in which the landscape of the whole city of Kyoto of the early Edo era (ca 17C) is reconstructed.

Virtual Yamahoko parade in virtual Kyoto

Recently, extensive research has been undertaken on digital archiving of cultural properties in the field of cultural heritage. These investigations have examined the processes of recording and preserving both tangible and intangible materials through the use of digital technologies.

Development of a High-Definition and Multispectral Image Capturing System for Digital Archiving of Early Modern Tapestries of Kyoto Gion Festival

We developed a two-shot 6-band image capturing system consisting of a large-format camera, a customized interference filter, and a scanning digital back to capture a 185-M-pixel images. The interference filter is set in front of the camera lens to obtain a 6-band image, that is, two 3-band images, one taken with the filter and the other without it. After correction of optical aberrations caused by the interference filter as well as system arrangement errors, the two images are combined into a 6-band image. The 6-band image was converted into a color-managed RGB image embedded ICC profile. In experiments, object images were captured as several divided parts and synthesized as almost 500-M-pixel image by using an image stitching technique. Resolution of the captured images is 0.02 mm/pixel. This paper discusses the camera system with its focus on some early modern tapestries used in the Kyoto Gion Festival. After the experiments, we interviewed a craftsman to assess the image’s importance in archiving and analyzing fabric structures.

Virtual Kyoto project: digital diorama of the past, present, and future of the historical city of Kyoto

Using the recently developed 3D GIS (Geographic Information System) and related visualisation technologies, we have created a digital diorama of an entire historical city, which can be used to virtually travel through different realistic landscapes at different times in the history. The digital diorama called Virtual Kyoto is the virtual geographic environment of the past, present, and future of the historical urban spaces in Kyoto City by constructing geotemporal-referenced 3D models of cityscape elements at different eras. In order to promote digital humanities studies on the arts and culture of traditional Kyoto, Virtual Kyoto is used as a digital platform for constructing a web-based digital museum interface with geographic data-linkages to numerous historical and cultural digital contents. We also explore the possibility of using Virtual Kyoto as an information environment to discuss the future of the historical city of Kyoto with the effects of city planning activities such as landscape policies or the possible damage due to disasters on historical landscapes.

GIS and quantitative geography

The purpose of this paper is to explore the development of the GIS revolution within the field of geography in the 1980s and 1990s, taking into consideration the influence of external and internal factors on disciplinary change. Geography is rapidly changing by the impact of external factors on geographical research and also as a consequence of economic recession and cutbacks in higher education. Most geography departments in universities have tried to approach this impact by promoting or shifting to human geography as an applied science, and by offering relevant skills through GIS as an approach to contemporary problems. It is concluded that quantitative geography is essential for the further expansion of GIS within geography and also for the survival of geography.

Presentation of japanese cultural event using virtual reality

With the development of computer graphics and virtual reality technologies, extensive researches have been carried out on digital archiving of cultural assets. In this paper, we introduce our work on presenting a traditional Japanese cultural event, namely Yamahoko Parade in Kyoto Gion Festival, using the latest technologies such as 3D CG modeling, motion capture, high-quality sound recording, vibration system, immersive virtual environment, and real-time interaction. This work is one part of the digital museum project, which intends to preserve and present Kyoto citys culture and tradition.