Izumi Takeuti

On Embedding a Qualitative Representation in a Two-Dimensional Plane

Abstract This paper discusses embedding in a two-dimensional plane a symbolic representation for spatial data using the simple objects, points (P), lines (L), circuits (C), and areas (A). We have proposed PLCA as a new framework for a qualitative spatial reasoning. In a PLCA expression, the entire figure is represented in a form in which all the objects are related. We investigate the conditions for two-dimensional realizability of a PLCA expression, and derive the relation that the numbers of objects in a PLCA expression should have. In this process, we use the well-known Eulers formula. We also give an algorithm for drawing the figure of the PLCA expression that satisfies this condition in a two-dimensional plane and prove its correctness. The algorithm generates a quantitative expression from qualitative expression.

Syntax and Semantics of Workflows That Include Passbacks

The questions of how to represent passbacks (redoing) of work in a workflow and of what semantics to apply to passbacks comprise an important issue in workflow research. In this paper, cyclic workflows are regarded as workflows with passbacks, and the normal form of a workflow is defined from properties of workflows as graphs. For a normal workflow, semantics based on passbacks is defined as a transition system on subgraphs of the workflow. Based on the transition system, this paper defines total correctness of a workflow with passbacks. Furthermore, this paper proves that total correctness of workflows with passbacks, defined in this paper, is a natural extension of the conventional correctness of acyclic workflows. This paper also shows that the correctness of a normal workflow amounts to the correctness of the acyclic sub-workflows included in the normal workflow.

Graphical representation of quality indicators based on medical service ontology

For recent years, it has grown importance to evaluate medical service qualities of medical staffs and/or hospitals by using quality indicators. This paper introduces a representation system QI-RS of quality indicators. By using QI-RS, one can define quality indicators that satisfy understandability and formality, where “understandability” means that one can understand the calculation formula of a quality indicator easily and correctly, while “formality” means that the formula can be calculated to obtain the values of the indicator based on databases in a coherent manner.