NCJ Number
113485
Date Published
1987
Length
59 pages
Annotation
In 'A Hypercube Model for Facility Location and Redistricting in Urban Emergency Services' (1974), Richard C. Larson presents a set of algorithms for modeling emergency vehicle dispatch and response to be used in planning strategies for resource allocation. This paper describes the implementation of a graphical method of user input for a requisite data set that uses a color graphics workstation.
Abstract
A central element of the model is the assignment of reporting areas -- numbered areas of several city blocks used to identify the general location from which calls for assistance are issued. A description of the numeric interface and its problems and a summary of graphic interface requirements are provided. Functional specifications are presented for the Apollo Graphics workstation; system functions; outputs, inputs, and their formats; and internal data formats. Transfer of picture from digitizer to workstation and drawing reporting areas on a map are described. Data transfer and format are discussed, and implementation techniques are delineated. The new interface makes the input process quicker and less error-prone by allowing the user to draw reporting areas on the workstation screen with a mouse instead of typing a long series of x and y coordinates. The method requires a minimum set of operations, additional features can be added, and bugs can be easily remedied. The major limitation is the restriction of having only 16 colors on the screen at once, making it difficult to use better quality maps or aerial photographs. Specifications are appended. Figures. (Author abstract modified)