This paper develops an exploratory method for analyzing the spatial relationship between two continuous surfaces. First, we classify the spatial relationship between two continuous surfaces into two categories: a "local relationship" and a "global relationship", and mathematically formulate these relationships. Second, we propose an index for the local relationship between two continuous surfaces. Third, we introduce a "contour tree" of a continuous surface, describe a qualitative characteristic of a continuous surface using a contour tree, and propose a method for exploring both local and global relationships. Last we apply the method to numerical examples and then show its effectiveness.

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Recently a novel data model named implicit topology description was proposed, and the concept has been adopted actual GISs and digital map editing systems. Since the data model is simple, it is advantageous to spatio-temporal GIS. This characteristic is caused by the method on which the topology is restored when it is required. However, the data model has not become leading methodology. A primary factor is that it needs much computational time. This paper proposes a method to shorten the processing time on GIS adopting implicit topology description. Then, the method is evaluated through two experiments, finding shortest path and restoring region.

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This paper aims to measure the positional accuracy of digitized point data by mouse operation. Fifteen operators digitized 225 representative points of buildings in the experiment designed with Latin square. The frequency distributions of X and Y deviations between digitized point locations and the centers of gravity of buildings on the original drawing are more peaked relative to the normal distribution. An analysis of variance and multiple comparison show that the differences among building coverage and among operators are significant. Substituting estimated deviations into a formula made by Teraki(1999), this paper estimates the probability of identifying buildings by the point-in-polygon interpolation.

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Definition and standardization about quality of spatial data are being developed for the purpose of making or using the most suitable spatial data to meet requirements of geographical information systems. However, since the new concept about this quality is much different from the present concept about quality uniformly decided only by map scale, the new concept has not spread widely. So, in the current clearinghouses used for searching spatial data, there is no function to search based on the quality of spatial data. In this paper, we propose a support system to describe product specification of spatial data. We explain the system architecture, procedure for describing product specification, method of defining the quality data and product specifications based on XML, and the spatial data retrieval method using the quality information in our clearinghouse.

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There are three main threads of landuse change modelling: urban economics, Markov process, and cell automaton. The purpose of this research is to integrate them by using logistic regression models to build a more realistic landuse change model. Especially, the model distinguishes two types of changes: whether landuse change occurs and which landuse category a present one will be when the change occurs. In the case of Osaka city, the neighbourhood condition which has 250 m spatial extents significantly contributed to the landuse change as well as accessibilities and zoning conditions. Finally, the concentric and asymmetrical structures of potential landuse changes are shown based on the calibrated model.

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This paper proposes the application of GIS for evaluating the sustainable use of forest biomass energy. The study area is Haramachi city in Fukushima prefecture (Population: 50, 000; Area: 19, 849ha; Forest Area; 11, 551ha). In our study, the geographical criteria of forest, such as slope and the position of road, and the criterion about the methods of logging are taken into consideration. 147 cases that are framed from these criteria are evaluated. As a result, for example, the forest in the city can generate 21.12% of the power consumption of the city, in the maximum case. And then, we consider GIS to be effective for evaluating the sustainable use of forest biomass energy.

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This paper presents an expanded definition for measuring geometric attributes such as size, shape and location in irregular zones. The expanded definition involves identifying size with area, shape with edge roughness or smoothness and compactness, location with number of adjacent zones and distance to the central zone. A zone which has special geometric attributes and keeps significant spatial correlation and spatial interaction closely to adjacent zones is called prominent zone in regional science. The prominence of zone can be measured by prominence index which is a stationary distribution of Markov chains transition matrix identical to a spatial weight matrix. In this study, spatial clusters composed of prominent zones are extracted using by K-means cluster analysis, and relations between prominence and geometric attributes of irregular zones are showed by correlation analysis. This study reveals that prominence index and geometric attributes provide effective measurements to evaluate prominence of irregular zones.

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There is growing interest in the environmental conservation functions of green resources. This paper focuses on the evaluation of these functions, such as air cooling, air purification, CO₂ fixation, and habitat conservation, by the use of existing GIS digital maps in order to create a community-based environmental program. This study also intends to show the existing and future environmental functions through the help of dynamic evaluation to related parties, including residents, who do not have special knowledge of environmental issues. It has an advantage of presenting the obtained results graphically and comprehensively in a geographic display.

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Recently, barrier-free maps have been developed. They are useful systems for the physically handicapped persons or their supporters. However, it is important to build an effective system, because existing systems especially lack connections of the information. In this paper, we propose a barrier-free information sharing map system based on the features of basic functions in the existing systems. This system is characterized by introduction of card image data structure that is linked with a map. Users of the system can add new information to stored one, relate to each other, and evaluate information, as well as register information on the map, in a unified way. We developed a prototype system using XML (eXtensible Markup Language). Through evaluation of the prototype system, it was proved that our proposed system was effective for users.

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Understanding travel behavior is essential for urban transportation planning. This paper presents the development of a GIS-based system for understanding individual travel behavior under space-time constraints and its application to the graduate class of environmental information system in spatial planning and policy. Required input data consist of activity schedules, transportation networks and activity opportunities. Potential Path Area (PPA) and the feasibility of participating in activities in space-time prisms can be simulated and represented on GIS, before and after changing constraints. The system is very useful for students to understand activity-travel behavior in urban space.

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In this paper, we propose a position-aware information delivery system for communication in mobile environments. Recently, mobile information terminals such as PDAs and cellular phones are widely spreaded. Therefore, it is important that the method to exchange and share information which is provided by users in mobile environments using their mobile information terminals. Our proposed system consists of a bulletin board system (BBS) which extended the function by the position information. We add the position information to comments and rooms in BBS, and calculate the fitness of a comment from the position information of a user and a comment. Moreover, the presentation priority of a room is calculated by the fitness of comments in a same room. A user can get rooms and comments which are suitable for his position. Furthermore, we explain our prototype system based on our proposed method.

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This paper points out that the records of "block level spatial reference data" don't reflect the centroid of plural polygons for unique address. To improve accuracy of block's centroid, we suggest to recalculate centroid of block using "Digital Map 2500". This method involves dissolving polygons that have identical address using ArcView8.1. Generated multipart polygon improved accuracy by an average of 30m for non-unique, 5.6m for unique records. Importance of data maintenance is also discussed.

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In this paper, I attempt to study the role of GIS in secondary geographical education. GIS's analyses are related to geographical viewpoint, so GIS should take part in positively making curriculum of geographical education and teaching materials. GIS's processes are useful for training of citizenship. By using GIS, we are able to improve secondary geographical education.

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