A structural active-object systems (SAOS) is a, transition-based object-oriented system consisting of a collection of interacting structural active objects (SAOs), which can be structurally and hierarchically composed from their component SAOs. The behaviors of SAOs are determined by the transition statements provided in their class definitions. Various concurrent systems such...
Existing graphics systems are too large for students to study in an introductory computer graphics course. We have implemented a lightweight, object-oriented graphics system called OGS for instruction. OGS is written in Java. It demonstrates how a graphics system is implemented from scratch and is intended to help students understand...
In this paper, we describe a software mechanism, a software channel, that allows a group of distributed objects to communicate with each other automatically once they are connected to it. Software channels and predesigned distributed objects that are connected to them encapsulate the communication protocol and the network topology to...
The SAOS Road Network Simulator (SARNS) is a graphical simulation program for transportation planning, implemented using the structural active-object system (SAOS) approach. A SAOS is an object-oriented concurrent system that consists of a collection of interacting structural active objects (SAOs), whose behaviors are determined by transition statements provided in their...
We have developed a framework for Web-based GIS/database applications which allow users to insert, update, delete, and query data with a map interface displayed by Web browsers. The framework was designed so that a Web-based GIS application that uses ArcIMS as a map server can be easily created, customized, and...
Web-Site Generator 3 (WebSiteGen3) is a rapid application development (RAD) tool that generates ASP.NET forms to insert, query, update and delete data stored in the user tables in a SQL Server 2000 database. WebSiteGen3 uses a graphical user interface to show the user tables in a hierarchical tree based on...
WEPP (Water Erosion Prediction Project) is a stand-alone Windows application for predicting water erosion from overland flow on a hillslope. This application was developed by the National Soil Erosion Research Laboratory (NSERL). To make the WEPP application more accessible and easy to use, we created a web version of WEPP,...
The WEPP (Water Erosion Prediction Project) application computes soil loss and sediment yield from a field based on the data on crops, management practices, and operations. In order to make WEPP, which is a Windows-based application, easily accessible, Web WEPP (Web-based WEPP) was developed by our research group.
Web WEPP...
Forms are the most common means of interacting with databases. Database develop1;11ent products offer differing capabilities for creating forms. We will compare the form design features available using 4th Dimension and Oracle database products. These two products have the most complete set of features compared to other micro computer database...
We have developed a prototype web-based GIS application for tracking the locations of moving entities. This application, which is called the Responder application, consists of two parts: the Responder client and the Responder server. The Responder client is a .NET application written in C#. It reads the location data from...