Abstract Soft systems methodology (SSM) is an approach for tackling problematical, messy situations of all kinds. It is an action-oriented process of inquiry into problematic situations in which users learn their way from finding out about the situation, to taking action to improve it. The learning emerges via an organised process in which the situation is explored using a set of models of purp...

A promising technique used in some planning systems to improve their performance is the use of domain dependent search control knowledge. We present a procedure for compiling search control knowledge, expressed declaratively in a logic, into the preconditions of the plan actions (operators). We do this within the framework of the situation calculus by introducing a transformation of nonMarkovia...

Reasoning about perception of depth and about spatial relations between moving physical objects is a challenging problem. We investigate the representation of depth and motion by means of depth profiles whereby each object in the world is represented as a single peak. We propose a logical theory, formulated in the situation calculus (SC), that is used for reasoning about object motion (includin...

By using an example from a robot navigating domain, we argue that to specify declaratively the behavior of an agent, we need to have a formal and explicit notion of \quality plans." To that end, we propose the following three domain independent measures of plan quality: a plan is said to be A-minimalif none of the actions in it can be deleted and have it continue to be a plan; it is said to be ...

We present a declarative formalization of STRIPS [1] as a reasoning strategy in the situation calculus [10]. The idea is to use logic not only to represent planning problems, but also to describe the mental situations, mental actions and reasoning strategy STRIPS uses to solve those problems.

In this paper we study the diierences between two logic theories for temporal reasoning, the Situation Calculus and the Event Calculus, and the implications of these diierences. We construct a new formalism that combines the advantages of both Situation and Event Calculus and avoids the problems of either. The new formalism is useful for general temporal reasoning in worlds with discrete and co...

The accessibility constraints imposed on anaphora by dynamic theories of discourse are too strong because they rule out many perfectly felicitous cases. Several attempts have been made by previous authors to rectify this situation using various tactics. This paper proposes a more viable approach that involves replacing Heim’s notion of familiarity with a generalized variant due to Roberts. This...

This paper reviews recent results obtained in the medical diagnosis field by adding to a coherent inference process qualitative constraints. Such further considerations turn out to be significant whenever a basic lower-upper conditional probability assessment induces extension bounds too vague to take any decision. Three general types of qualitative judgements are proposed and fully described. ...

Managing complications after attempted hind foot and ankle arthrodesis with intramedullary nail fixation is a challenge. This situation becomes more problematic in the patient with diabetes mellitus and multiple comorbidities. Infection and subsequent osteomyelitis can be a devastating, limb threatening complication associated with these procedures. The surgeon must manage both the infectious p...