Leadership depends on the situation. Few social scientists would dispute the validity of this statement. But the statement can be interpreted in many different ways, depending, at least in part, on what one means by leadership. This article begins with a definition of leadership and a brief description of 3 historically important theories of leadership. The most recent of these, contingency the...

Problem statement: An emergency system of sharing and exchanging user’s personal information is demanded in medical treatment and disaster situations. Approach: In such a system, personal information access control depending on user situations is greatly necessary. However, it is complicated to manage personal information access control directly, because the existing access control methods onl...

• Each table in the database has one column and stores the possible values for a ground fluent term. •Whenever there is complete knowledge about the term, the corresponding table has exactly one row. E.g., the ground fluent term door has only one possible value (Closed ) and so the table for door has exactly one row: Closed. •Whenever there is incomplete knowledge, the table has more than one r...

paper, we attempt to reconstruct the sitcalculus on a dense flow of time. The

We utilize the situation calculus to develop a logical model of hypertext systems. The work builds upon the earlier work of Bieber and Kimbrough in the logical modeling of hypertext systems. In our presentation, a particular version of the situation calculus (which includes a language for programming complex actions) developed for the modeling of dynamic worlds and for the control of robotic ag...

Mathematical models for the electrical activity in cardiac cells are normally formulated as systems of ordinary differential equations (ODEs). The equations are nonlinear and describe processes occurring on a wide range of time scales. Under normal accuracy requirements, this makes the systems stiff and therefore challenging to solve numerically. As standard implicit solvers are difficult to im...

Water quality management policies on a river basin scale are of special importance in order to prevent and/or reduce environmental pollution caused by human sources. Industrial effluents are a priority issue particularly in Urban Wastewater Systems (UWS) that receive mixed household and industrial wastewaters, apart from rainfall water. In this paper, we present an analysis and implementation o...

Shapiro et al. [2005; 2006], presented a framework for representing goal change in the situation calculus. In that framework, agents adopt a goal when requested to do so (by some agent reqr ), and they remain committed to the goal unless the request is cancelled by reqr . A common assumption in the agent theory literature, e.g., [Cohen and Levesque, 1990; Rao and Georgeff, 1991], is that achiev...

The situation calculus is one of the most established formalisms for reasoning about action and change. In this paper we will review the basics of Reiter’s version of the situation calculus, show how knowledge and time have been addressed in this framework, and point to some of the weaknesses of the situation calculus with respect to time. We then present a modal version of the situation calcul...