Expert Systems
Report 77-07 Stanford -- KSL
Both tasks are concerned with the interpretation of large quantities of digitized signal data. The task of SU/X is to understand "continuous signal that is, signals which persist over time. The task of SU/P is to interpret protein x-ray crystallographic data. Some features of the design are: (1) incremental interpretation of data employing many different pattern-invoked sources of knowledge, (2) production rule representation of knowledge, includiR high level strategy knowledge, (3) "opportunistic" hypothesis formation using Dr,
Report 77-05 A Review of Knowledge-Based Problem
It is generally accepted that problem solving systems require a wealth of domain specific knowledge for effective performance in complex domains. This report takes the view that all domain specific knowledge should be expressed in a knowledge base. With this in mind, the ideas and techniques from problem solving and knowledge base research are reviewed and outstanding problems are identified. Finally, a task domain is characterized in terms of objects, actions, and control/strategy knowledge and suggestions are made for creating a uniform knowledge base management system to be used for knowledge acquisition, DD "" 1473
Report 77 04 Application of Artificial Intelligence for Stanford Chemical Inference . Tom M. Mitchell Gretchen M.
The increasing popularity of 13 C techniques and the increasing bulk of available data have motivated us to develop a computer program which generates empirical 13 C NUR rules. A natural abundance 13 C NMR spectrum which is fully proton-- decoupled consists of a number of sharp peaks ccrresponding to the resonance frequencies in the applied magnetic field of the various types of carbon atoms present in the sample. A 13 C shift is the amount a peak position deviates from a reference peak of a standard compound usually tetramethylsilane (T1s). Methods for obtaining empirical rules which correlate 13 C shifts with local structural environments within a class of compounds are cited in the literature.
Submitted to MEDINF0.77
Almost one-half of the total cost of drugs spent in treating hospitalized patients is spend on antibiotics (1,2), and a significant part of this therapy is associated with serious misuse (2,3,4,5). One problem involves incorrect selection of a therapeutic regimen [4], while another involves the incorrect decision to administer any antibiotic (2,4,5). For example, one recent study concluded that one out of every four people in the United States was given penicillin during a recent year, and nearly 907. of these preL,criptions were oahccessary (6).
Report 77-02 A Knowledge-Based System for the Interpretation
A Glossary of Terms Used in Protein Crystallography.. - - - - A KNOWLEDGE-BASED SYSTEM FOR THE INTERPRETATION OF PROTEIN X-RAY CRYSTALLOGRAPHIC DATA ABSTRACT The broad goal of this project is to develop intelligent computational systems to infer the three-dimensional structures of proteins from x-ray crystallographic data. The computational systems under development use both formal and judgmental knowledge from experts to select appropriate procedures and to constrain the space of plausible protein structures. The hypothesis generating and testing procedures operate upon a variety of representations of the data, and work with several different descriptions of the structure being inferred. The system consists of a number of independent but cooperating knowledge sources which propose, augment and verify a sol.uticn to the problem as it is incrementally generated.
EXPLANATION CAPABILITIES OF PRODUCTION-BASED CONSULTATION SYSTEMS
ABSTRACT A computer program that models an expert in a given domain is more likek to be accepted by experts in that domain, and by non-experts seeking its gavice. An explanation capability not only adds to the system's credibility, but also enables the non-expert user to learn from it. Furthermore, clear explanations allow an expert to check the system's "reasoning", possibly discovering the need for refinements and additions to the svstem's knowledge base. In a developing system, an explanation capability can be used as a debugging aid to verify that additions to the system are working as'hey should. The explanation facility in MYCIN is discussed as an illustration of how the various problems might be approached.
The Anti-Expert System: Hypotheses an AI Program Should Have Seen Through Joshua Lederberg
One of the most difficult steps in the development of an expert system is the recruitment and exploitation of the domain wizards. Almost always it is necessary to establish teams of specialists to deal with the programming issues and the user interfaces as well as the incorporation of domain specific knowledge. Experts will communicate how they read a gel, or what is the canonical biological interpretation of DNA sequences conserved over phyletically diverse organisms. The computer scientist will rarely have an independent base of knowledge and experience for critical judgments about the wisdom thus received. Therein may lie the greatest hazards from the proliferation of expert systems; for much of that expertise is fallible.
A Qualitative Biochemistry and Its Application to the Regulation of the Tryptophan Operon
This article is concerned with the general question of how to represent biological knowledge in computers such that it may be used in multiple problem solving tasks. In particular, I present a model of a bacterial gene regulation system that is used by a program that simulates gene regulation experiments, and by a second program that formulates hypotheses to account for errors in predicted experiment outcomes. This article focuses on the issues of representation and simulation; for more information on the hypothesis formation task see (Karp, 1989; Karp, 1990). The bacterial gene regulation system of interest is the tryptophan (trp) operon of E. coli (Yanofsky, 1981). The genes that it contains code for enzymes that synthesize the amino acid tryptophan.