The solution to this simple problem would then guide the solution of the original problem. Minsky (1961) has discussed complex planning of this'homomorphic model' type, and has stressed the potential reduction in total search effort to be won. In the same paper he has also considered the use of semantic models' as a form of complex planning in a mathematical context. The successful geometry theorem-proving program of Gelernter (1959), which used a diagram' to test the validity of propositions, is a wellknown example of this form of planning. Recently Sandewall (1969) has defined a Planning Problem Solver (P P This is an attempt to explore in detail complex planning of the homomorphic model' type as applied to the

A new method for automated planning, progressive refinement of skeletal plans, has been developed for the problem of experiment design in the domain of molecular biology. The method resulted from a study of the problem-solving behavior of scientists which showed that design usually consisted of lookup of abstracted plans followe6 by hierarchical plan-step refinement. The skeletal plan method has been implemented through two generations of problem-solving systems: the second generation involving a synthesis with the metaplanning approach of Stefik.

Ihe control problem--which of its potential actions should an Al system perform at each point in the problem -solving process?-- is fundamental to all cognitive processes. To solve the control problem intelligently, Al systems should achieve (at least) the seven behavioral goals set forth in this paper. The paper proposes a blackboard model of control and shows how it achieves the goals. The pdper contrasts the model with three alternative control models and shows how it continues an evolutionary progression of control architectures.

No. STAN-CS-82-909 Also numbered: HPP42-7 Department of Computer Science Stanford University Stanford, CA 94305 Abstract This paper describes the student modeler of the GUIDON2 tutor, which understands plan: by a dual search strategy. It first produces multiple predictions of student behavior by a model-driven simulation of the expert. Focused, data-driven searches then explain incongruities. By supplementing each other, these methods lead to an efficient and robust plan understander for a complex domain. Diagnostic problem-solving requires domain knowledge and a plan for applying that knowledge to the problem.

The selection of what to do next is often the hardest part of problem solving. This selection can be structured by di,'Mguishing decisions about the problem from decisions about the problem solving process. When planning decisions are structured in this way, we find that many of the most important decisionc, are about the planning process itself. This exercise tends to expose a variety of decisons, which are usually made implicitly and sub-optimally in planning programs with rigid control structures. This paper develops a layered approach for meta-planning, that is, for planning about planning. It is part of a course of research which seeks to enhance the power of a problem solver by enabling it to reason about its own reasoning processes.

Section 1 1 Introduction The MOLGEN project has focused on research Into the applications of symbolic computation and Inference -to the field of molecular biology. This has taken the specific form of systems which provide assistance to the experimental scientist in various tasks, the most important of which have been the design of complex experiment plans and the analysis of nucleic acid sequences. During the period of further research proposed in this document, we plan to expand and improve these systems and build new ones to meet the rapidly growing needs of the domain of recombinant DNA technology. We do this with the view of including.

There are several different types of goals, and each has a corresponding set of parameters. For example, the goal (obtain (coefficient 6 x 2)) means to obtain an expression for the coefficient of x2 in g6, either to print it out or pass as argument to some MACSYMA command. Note that this can be done either by finding an already computed expression (stored, say, as the value of some variable) or by computing it anew. Either implementation is satisfactory so long as it computes the desired expression.

The parser le following paragraphs describe both.

This article describes the DSN scheduling wngine (DSE) component of a new scheduling system being deployed for NASA's deep space network. The DSE provides core automation functionality for scheduling the network, including the interpretation of scheduling requirements expressed by users, their elaboration into tracking passes, and the resolution of conflicts and constraint violations. It has been integrated with a web application which provides DSE functionality to all DSN users through a standard web browser, as part of a peer-to-peer schedule negotiation process for the entire network. The system has been deployed operationally and is in routine use, and is in the process of being extended to support long-range planning and forecasting, and near-real-time scheduling.

As planetary rovers expand their capabilities, traveling longer distances, deploying complex tools, and collecting voluminous scientific data, the requirements for intelligent guidance and control also grow. This, coupled with limited bandwidth and latencies, motivates onboard autonomy that ensures the quality of the science data return. Increasing quality of the data involves better sample selection, data validation, and data reduction. Robotic studies in Mars-like desert terrain have advanced autonomy for long distance exploration and seeded technologies for planetary rover missions. In these field experiments the remote science team uses a novel control strategy that intersperses preplanned activities with autonomous decision making. The robot performs automatic data collection, interpretation, and response at multiple spatial scales. Specific capabilities include instrument calibration, visual targeting of selected features, an onboard database of collected data, and a long range path planner that guides the robot using analysis of current surface and prior satellite data. Field experiments in the Atacama Desert of Chile over the past decade demonstrate these capabilities and illustrate current challenges and future directions.