The development of GIS technology has made it available to a growing number of people from different disciplines and different backgrounds. However, the degree of productivity that they can achieve is limited by their lack of technical knowledge about GIS tools. Interface agents are software tools oriented to reduce the gap between user's knowledge and GIS technical knowledge required to achieve their goals. This paper describes a knowledge-based interface agent for ArcInfo whose mission is to help ArcInfo users to access and process spatial data stored in ArcInfo databases. We are assuming that the user is not familiar with ArcInfo nor with the content and structure of the ArcInfo database and that he/she is not necessarily working in the same machine in which ArcInfo is available. Our interface agent, using a client-server schema, is able to operate on a LAN or WAN network, to receive and process requests written in plain English interacting with the user in case of possible mismatches between his/her concepts and the representation of data in the ArcInfo database, to build and send sequences of commands oriented to provide the information requested by the user to an ArcInfo server, and to receive and present the results of those request to the user. A prototype of the interface agent was built using SNePS (Semantic Network Processing System) and Common Lisp on top of a Sun SPARC station.
ArcInfo, as compared to other GIS, is relatively rich in its analytical functions. It has built-in modules for advanced spatial models, such as the spatial interaction model and location-allocation model. These models incorporated in ArcInfo utilize pertinent geographic information for spatial analysis and modeling, such as topology, stored in ArcInfo. However, various types of geographic information cannot be used flexibly inside ArcInfo for other spatial analytical techniques and modeling. This paper demonstrates how segregation study using spatial indice, which cannot be calculated without GIS and the spatial information stored in ArcInfo become feasible by combining ArcInfo with other tools. Several types of spatial information are extracted from ArcInfo and are transferred to S-plus, a very sophisticated statistical package. Using various data manipulation functions and procedures in S-plus, different types of spatial information are then combined with attribute data to calculate a family of spatial segregation indices.
The success of a research product is determined by its ability to synthesize and convey its data in a simple and meaningful manner for the investigator to interpret. This task may become quite challenging when the data base is large and relates to a broad geographical area. The graphical display environment and database capabilities of ArcInfo facilitate data interpretation with graphical displays and powerful data query capabilities. The flexibility of ARC Macro Language is that it allows the creation of a total window driven interface environment that provides the interpreter immediate access to the data without having to learn new GIS theories or software. In this manner the focus is on data interpretation rather than data manipulation. The purpose of this paper is to discuss the developmental issues of creating such a graphical interface. I have created an interface that displays the geographical distribution of mammals, reptiles, birds and plants in the Great Basin over the last 25,000 years. Supplementing the display are several database query features. The database is voluminous, consisting of data from over 125 archeological and paleontological sites in the Great Basin. The purpose of the interface is assist in the interpretation of paleoenvironments. Emphasis of the interface is placed on performing meaningful data queries with parameters defined by the user, cogent displays, and ease of use.
Developing and maintaining large spatial databases is a laborious, error prone, and costly process. A comprehensive and intuitive Graphical User Interface (GUI) with easily accessible editing tools can increase the speed and ease of developing and maintaining large databases. In addition, an editing environment with the ability to track and log edits, automatically assign and manage unique record IDs, and the capability for recovering earlier changes made to a single or multiple features can reduce the amount of error and cost in the final product. The purpose of this paper is to describe a case study in the development and use of a topological editing shell for ARCEDIT. The system was developed for the Department of Transportation's Bureau of Transportation Statistics and Federal Highway Administration. The paper will examine the design and layout of the GUI, the methods used to transparently archive edits and record and assign new record IDs, and the mechanisms used to recover features modified in the past.