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New Improvements in Automatic Structure Elucidation Using the LSD (Logic for Structure Determination) and the SISTEMAT Expert Systems

PLAINCHONT, Bertrand; NUZILLARD, Jean-Marc; RODRIGUES, Gilberto V.; FERREIRA, Marcelo J. P.; SCOTTI, Marcus T.; EMERENCIANO, Vicente P.
Fonte: NATURAL PRODUCTS INC Publicador: NATURAL PRODUCTS INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
75.87%
This article describes the integration of the LSD (Logic for Structure Determination) and SISTEMAT expert systems that were both designed for the computer-assisted structure elucidation of small organic molecules. A first step has been achieved towards the linking of the SISTEMAT database with the LSD structure generator. The skeletal descriptions found by the SISTEMAT programs are now easily transferred to LSD as substructural constraints. Examples of the synergy between these expert systems are given for recently reported natural products.; CNRS; Centre National de la Recherche Scientifique (CNRS)

Desenvolvimento de um sistema especialista para auxilio no projeto e operação de processos biotecnologicos; Expert system development for aid n the Bioprocesses design and operation

Vera Lucia Reis de Gouveia
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 23/02/2006 PT
Relevância na Pesquisa
75.89%
Os processos biotecnológicos ou Bioprocessos necessitam de maiores cuidados do que a maioria dos processos químicos comuns devido, principalmente, à sensibilidade a variações nos estados do sistema como, por exemplo, temperatura e concentração. O crescente aumento da importância dos Bioprocessos e a maior dificuldade em seu controle e simulação resultaram na procura e utilização de novas ferramentas como a Inteligência Artificial (IA). Inteligência Artificial é uma parte da ciência da computação relacionada ao projeto de sistemas computacionais inteligentes. Nos últimos anos houve um aumento substancial do uso de ferramentas de IA tais como Redes Neurais Artificiais (R.N.A), Sistemas Especialistas e Lógica Fuzzy no controle e simulação de Bioprocessos. Este trabalho teve como objetivo o desenvolvimento de um software que atue como um assistente, auxiliando na simulação de Bioprocessos. O Bio-PSA (BioProcess Simulation Assistant) possui quatro módulos: Módulo 1: Simulação de Bioprocessos, incluindo funcionalidades para simulação de produção de etanol e dextrana, ambos com modelagem normal e híbrida. Módulo 2: Simulação de processos para purificação de proteínas, incluindo a modelagem de processos baseados no modelo CARE (Continuous Affinity Recycle Extraction). ?Módulo 3: Sistema Especialista e uma base de conhecimento que auxilia o usuário no design de processos biotecnológicos. Módulo 4: Software para treinamento de R.N.A; The biotechnical processes or Bioprocesses require larger cares than common chemical processes due...

Ferramenta de aquisição de conhecimento por modelos explicitos

Marcos Melo Schiavini
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/02/1991 PT
Relevância na Pesquisa
65.87%
A tese apresenta uma contribuição para agilizar e organizar o processo de aquisição de conhecimento necessário ao desenvolvimento de sistemas Especialistas. Para tanto é descrita uma ferramenta computacional de auxilio ao processo de aquisição e engenharia de conhecimento - CAKE - que emprega um modelo do domínio durante sua interação com o especialista. O modelo é elaborado e representado com o auxílio do KADS, uma metodologia de construção de sistemas baseados em conhecimento [WIELINGA 89]. Com esse trabalho visamos obter uma ferramenta de aquisição de conhecimento que não apenas apresente as vantagens de empregar um modelo como também não tenha seu uso limitado a apenas um domínio particular. Para tanto concebemos uma ferramenta que deixa explícito o modelo utilizado para guiar o processo de aquisição de conhecimento. O engenheiro do conhecimento pode alterar a ferramenta para adequá-la às suas necessidades; The theses presents a contribution to facilitate and to organize the knowledge acquisition process necessary in the development of Expert Systems. A computer aided knowledge acquisition and engineering tool - CAKE -that employs a domain model in its interaction with the expert is proposed. The model is constructed and represented with the help of KADS...

Modeling and evaluation of expert systems in decisionmaking organizations

Perdu, Didier Marie-Joseph
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 105 leaves; 5542563 bytes; 5542322 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
85.71%
by Didier Marie-Joseph Perdu.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1988.; Bibliography: leaves 91-93.

An expert system for the management of hazardous materials at a Naval Supply Center

England, David C.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: vi, 94 p.
EN_US
Relevância na Pesquisa
75.87%
Approved for public release, distribution is unlimited; This thesis analyzes, designs and implements an expert system for the management of hazardous material at a Naval Supply Center (NSC). This system is part of a series of expert systems built by the Naval Postgraduate School to assist the Naval Supply Systems Command in automating its inventory management systems at NSCs. Selecting the proper storage conditions and location for newly received hazardous material requires the NSC's expert in such matters, the safety and health manager, to research the primary data base, the Hazardous Material Information System (HMIS), and any other relevant information sources, and extract the pertinent information. He determines the best storage conditions for the material and passes this information to the warehouse worker. The Hazardous Material Expert System (HAZMAT ES) will facilitate making the storage decision and will allow a warehouse worker to safely store hazardous material without the assistance of the safety and health manager.; Lieutenant Commander, United States Navy

Belief-Rule-Based Expert Systems for Evaluation of E- Government: A Case Study

Hossein, Shahadat; Zander, Par-Ola; Kamal, Md.; Chowdhury, Linkon
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
65.95%
Little knowledge exists on the impact and results associated with e-government projects in many specific use domains. Therefore it is necessary to evaluate the efficiency and effectiveness of e-government systems. Since the development of e-government is a continuous process of improvement, it requires continuous evaluation of the overall e-government system as well as evaluation of its various dimensions such as determinants, characteristics and results. E-government development is often complex with multiple stakeholders, large user bases and complex goals. Consequently, even experts have difficulties in evaluating these systems, especially in an integrated and comprehensive way as well as on an aggregate level. Expert systems are a candidate solution to evaluate such complex e-government systems. However, it is difficult for expert systems to cope with uncertain evaluation data that are vague, inconsistent, highly subjective or in other ways challenging to formalize. This paper presents an approach that can handle uncertainty in e-government evaluation: The combination of Belief Rule Base (BRB) knowledge representation and Evidential Reasoning (ES). This approach is illustrated with a concrete prototype, known as Belief Rule Based Expert System (BRBES) and put to use in the local e-government of Bangladesh. The results have been compared with a recently developed method of evaluating e-Government...

Building a logical model in the machining domain for CAPP expert systems

Kryssanov, V. V.; Kleshchev, A. S.; Fukuda, Y.; Konishi, K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/06/2006
Relevância na Pesquisa
65.93%
Recently, extensive efforts have been made on the application of expert system technique to solving the process planning task in the machining domain. This paper introduces a new formal method to design CAPP expert systems. The formal method is applied to provide a contour of the CAPP expert system building technology. Theoretical aspects of the formalism are described and illustrated by an example of know-how analysis. Flexible facilities to utilize multiple knowledge types and multiple planning strategies within one system are provided by the technology.; Comment: 25 pages, 4 figures. Preprint completed in 1997

Diagnosis expert system with automated query to a process control system

Winslow, Richard
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
65.84%
This thesis describes the development of a diagnosis expert system for an automated process control facility. To reduce the number of user responses to the expert system, a network interface was created between the expert system and the process control computer. This document focuses on the unique concerns associated with the development, validation, and implementation of an expert system that is directly interfaced to a process control system.

Automated knowledge acquisition for knowledge-based systems: KE-KIT

Parsons, John Scott
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
75.93%
Despite recent progress, knowledge acquisition remains a central problem for the development of intelligent systems. There are many people throughout the world doing studies in this area. However, very few automated techniques have made it to the market place. In this light, the idea of automating the knowledge acquisition process is very appealing and may lead to a break through. Most (if not all) of the approaches and techniques concerning intelligent, expert systems and specifically knowledge-based systems can still be considered in their infancy and definitely do not subscribe to any kind of standards. Many things have yet to be learned and incorporated into the technology and combined with methods from traditional computer science and psychology. KE-KIT is a prototype system which attempts to automate a portion of the knowledge engineering process. The emphasis is on the automation of knowledge acquisition activities. However, the transformation of knowledge from an intermediate form to a knowledge -base format is also addressed. The approach used to automate the knowledge acquisition process is based on the personal construct theory developed by George Kelly in the field of psychology. This thesis gives and in-depth view of knowledge engineering with a concentration on the knowledge acquisition process. Several issues and approaches are described. Greater details surrounding the personal construct theory approach to knowledge acquisition and its use of a repertory grid are given. In addition...

Teraphim: a domain-independent framework for constructing blackboard-controlled, blackboard-based expert systems in Prolog

Lyon, Bruce
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
85.91%
The blackboard architecture, in which a set of independent knowledge sources communicate by means of a global data base known as a blackboard, has been suggested as a generally useful design for knowledge-based systems. Teraphim is a domain-independent frame work for writing blackboard-based expert systems in Prolog. It implements concepts common to a range of previous blackboard architecture programs, such as HEARSAY-III and BB1. Teraphim includes as its basic elements a partitioned blackboard, a simple blackboard-controlled scheduler, a set of general-purpose scheduling heuristics to control the scheduler, a generic knowledge source with the ability to ask the user questions about incomplete data, modifiable methods of reasoning about uncertain data, and a simple explanation facility that traces the origins of terms on the problem blackboard. Trials of the system indicate that it can be used to implement expert systems to solve either synthesis or analysis problems. The blackboard architecture of Teraphim lends itself to experimentation with the kinds of knowledge representation and control knowledge needed to solve problems. Prolog proved to be a convenient language for writing blackboard-based systems.

FRIC: an expert system to recognize fricatives

Atkinson, Karen A.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
65.87%
In building a speaker independent continuous speech understanding sys tem, a method is needed to translate the speech signal to a phoneme string. Current recognition attempts based on statistical methods are not as accurate as desired and require vast numbers of templates for comparison. On the other hand, human experts can transcribe phoneme strings from spectrograms with a high degree of accuracy, without needing to match unidentified seg ments against identified templates. This paper discusses the development of Fric, an expert system for identifying fricative phonemes, intended to func tion as part of a phoneme identification knowledge source. Fric attempts to mimic the techniques used by human transcribers in identifying phonemes. RuleMaster, an expert system building tool developed by Radian Corporation, was used to create this system. Fric uses both forward and backward chaining as control strategies and includes an explanation system for both debugging and explanatory purposes.

A Comparative study of four major knowledge representation techniques used in expert systems with an implementation in Prolog

Hudgick, JoAnn T.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
85.87%
Knowledge representation is a central issue in Artifical Intelligence (AI) research. In order to solve the diverse and complex problems encountered, one needs both a large amount of knowledge and some mechanism for the management and skillful utilization of that knowledge. The basic problem in knowledge representation is the development of an adequate formalism to represent that knowledge. In this thesis I will discuss four of the major techniques for representing knowledge in expert systems: first order logic, production rules, semantic networks, and frames. Using Prolog as the implementation language, I will demonstrate that all of the above mentioned representation techniques, when used in actual implementations, will be reduced to an equivalency - that being a set of Prolog facts and rules. Prolog limits us to a set of facts expressed as "predicate(argumentl, argument, ..., argumentn)" and "IF ... THEN" rules, thus eliminating many of the unique features which characterize the various representation techniques. Therefore, Prolog can be viewed as a representation technique itself.

Geneplanner: A Prototype of an expert system to assist with chemical DNA gene synthesis planning

Daum, Marilyn
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
75.88%
Expert systems are a popular area of artificial intelligence. The development of an expert system involves the selection of an appropriate problem, acquisition of knowledge from the expert, selection of control mechanisms and knowledge repre sentations, selection of tools, implementation, and testing. This thesis describes the development of a prototype expert system in the area of genetic engineering. The prototype system suggests the fragments of DNA to chemically synthesize and the steps for joining these fragments in order to make a gene. The system follows the hueristic rules of an expert to select the fragments and strategy for synthesis, backtracking where necessary. After reviewing expert systems and the problem area, the thesis focuses on the development process. Each of the steps is discussed, and the iterative nature of implementation, testing, and refinement is displayed. Results are reviewed, showing Geneplanner to handle simple to moder ate cases fairly well. Finally, shortcomings are discussed and future enhancements are suggested.

A knowledge acquisition assistant for the expert system shell Nexpert-Object

Perot, Florence
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
65.94%
This study addresses the problems of knowledge acquisition in expert system development examines programs whose goal is to solve part of these problems. Among them are knowledge acquisition tools, which provide the knowledge engineer with a set of Artificial Intelligence primitives, knowledge acquisition aids, which offer to the knowledge engineer a guidance in knowledge elicitation, and finally, automated systems, which try to replace the human interviewer with a machine interface. We propose an alternative technique to these approaches: an interactive syntactic analyzer of an emerging knowledge base written with the expert system shell called Nexpert Object. This program intends to help the knowledge engineer during the editing of a knowledge base, both from a knowledge engineering and a knowledge representation point of view. The implementation is a Desk Accessory written in C, running on Macintosh "concurrently" with Nexpert Object.

A Toolkit for uncertainty reasoning and representation using fuzzy set theory in PROLOG expert systems

Bicker, Marcelle M.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
85.94%
This thesis examines the issue of uncertainty reasoning and representation in expert systems. Uncertainty and expert systems are defined. The value of uncertainty in expert systems as an approximation of human reasoning is stressed. Five alternative methods of dealing with uncertainty are explored. These include Bayesian probabilities, Mycin confirmation theory, fuzzy set theory, Dempster-Shafer's theory of evidence and a theory of endorsements. A toolkit to apply uncertainty processing in PROLOG expert systems is developed using fuzzy set theory as the basis for uncertainty reasoning and representation. The concepts of fuzzy logic and approximate reasoning are utilized in the implementation. The toolkit is written in C-PROLOG for the PYRAMID UNIX system at the Rochester Institute of Technology.

Expert systems in typography

Fisher, David B.
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
75.88%
Electronic publishing systems are providing authors with a tremendous amount of power formerly only available to printers: the choice of typographic design and layout. However, many authors use this power without the proper background, with potentially disastrous results. We have developed a prototype expert system that provides users of electronic publishing systems with the printer's knowledge in computer form in one narrow area of the publishing field to aid them in preparing their publications.

Enhancements to the frame virtual machine

Bhandari, Archna
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
65.92%
The Enhanced Frame Package is a tool to build Expert Systems. It is a frame based system, that initially was developed in C-Prolog by LaMora S. Hiss at Rochester Institute of Technology in 1987 for her master's thesis. It was enhanced in the current thsis to provide much larger expressive power andgreater ease of use. Several operators were modified/enhanced, and several new operators were added, while providing the user a balance of computational tractability, expressive power and consistency. Major concepts provided in the Enhanced Frame Package include - local consistency checking as opposed to global consistency checking and how the user can have the best of both options; the flexibility of loading a knowledge base file as a consistent system or as an inconsistent system; operations that work on working memory and operations that work on the original file in the working directory; the concept of a knowledge analyzer; the way one sees the human mind, knowledge and learning and its parallel in knowledge representation and the surrounding issues of consistency, expressive power and computational tractability.

Development of an expert system for identifying effective countermeasures at rural unsignalized intersections

Frey, Rebecca
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
Relevância na Pesquisa
75.84%
Faghri, Ardeshir; Intersections are among the most dangerous points in a transportation network. Both shortcomings in design and human error contribute to the frequency of crashes at intersections. In this thesis, a knowledge based expert system is created to assist engineers and transportation officials in the process of improving the safety at rural, unsignalized intersections. Currently, the process of identifying countermeasures for rural, unsignalized intersections with a chronic safety problem involves a great deal of experience and subjective assessments. The knowledge based expert system developed attempts to provide a more logical progression of the intersection safety process and incorporate quantitative assessments of potential options. The American Association of State Highway and Transportation Officials??? (AASHTO) 2010 publication, the Highway Safety Manual seeks to provide the first quantitative assessment of intersection safety countermeasures. These values are incorporated into the knowledge based expert system (KBES). The KBES for countermeasure identification is the result of a comprehensive literature search to identify and determine the effectiveness of countermeasures of rural, unsignalized intersections. The countermeasures considered in this project include intersection lane narrowing...

Knowledge acquisition for organisational problem solving : developing expert systems and beyond

Poulymenakou, Angeliki; Cornford, Tony; Whitley, Edgar A.
Fonte: London School of Economics and Political Science Research Publicador: London School of Economics and Political Science Research
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em //1992 EN; EN
Relevância na Pesquisa
75.77%
This paper examines the introduction of knowledge acquisition techniques to facilitate managerial and administrative problem solving. The characteristics of such problem situations do not lend themselves to normative approaches such as simply introducing expert systems. However appropriately performed knowledge acquisition can still be of benefit by providing a better understanding of problem situations and it can provide a suitable basis for the process of negotiation and compromise needed to resolve organisational problems. This emerging role for knowledge acquisition differs from that of systems analysis, for example, in that it focuses on improving the understanding of the location, ownership and impact of available organisational knowledge rather than the data flows and tasks performed within the organisation. The paper provides guidelines for performing knowledge acquisition for organisational problem solving.

Embedding expert systems in semi-formal domains : examining the boundaries of the knowledge base

Whitley, Edgar A.
Fonte: London School of Economics and Political Science Thesis Publicador: London School of Economics and Political Science Thesis
Tipo: Thesis; NonPeerReviewed Formato: application/pdf
Publicado em /04/1990 EN; EN
Relevância na Pesquisa
65.93%
This thesis examines the use of expert systems in semi-formal domains. The research identifies the main problems with semi-formal domains and proposes and evaluates a number of different solutions to them. The thesis considers the traditional approach to developing expert systems, which sees domains as being formal, and notes that it continuously faces problems that result from informal features of the problem domain. To circumvent these difficulties experience or other subjective qualities are often used but they are not supported by the traditional approach to design. The thesis examines the formal approach and compares it with a semiformal approach to designing expert systems which is heavily influenced by the socio-technical view of information systems. From this basis it examines a number of problems that limit the construction and use of knowledge bases in semi-formal domains. These limitations arise from the nature of the problem being tackled, in particular problems of natural language communication and tacit knowledge and also from the character of computer technology and the role it plays. The thesis explores the possible mismatch between a human user and the machine and models the various types of confusion that arise. The thesis describes a number of practical solutions to overcome the problems identified. These solutions are implemented in an expert system shell (PESYS)...