This paper presents an adaptive modeling technique for the identification and monitoring of drilling processes. The major dynamics of drill failure are captured by a threshold mixed model using the in-process drilling...
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This paper presents an adaptive modeling technique for the identification and monitoring of drilling processes. The major dynamics of drill failure are captured by a threshold mixed model using the in-process drilling vibration data. The threshold learning model and the initial guess parameters are evaluated from the first drilling hole signal. The parameters are updated by an adaptive scheme in the subsequent operations. Two control indices, the transient slope and the steady-state model residuals, are estimated. The process is monitored using a forecasting control chart generated from the control parameters. The monitoring result shows that the threshold approach is capable of predicting the wear state of a tool for various machining operations with a high variability of dynamic data.
The objectives of dynamic model verification are to produce a model which (1) is in agreement with test data, (2) will assist in the interpretation of test data, (3) can be used to help verify a design, (4) will relia...
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The objectives of dynamic model verification are to produce a model which (1) is in agreement with test data, (2) will assist in the interpretation of test data, (3) can be used to help verify a design, (4) will reliably predict performance, and (5) in the case of space structures, facilitate dynamic control. MOVER ii incorporates modal synthesis and substructuring techniques for modeling large multi-component systems and provides a variety of graphic outputs to facilitate interpretation of results. MOVER ii has been used to verify models of turbo-pumps rail vehicles, launch vehicles and high-speed rotating machinery.
Litton Guidance and control Systems is developing a thermal signature analysis method for the interpretation of Vanzetti laser inspection sensor data. It is believed that this method, when applied to solder joint proc...
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Litton Guidance and control Systems is developing a thermal signature analysis method for the interpretation of Vanzetti laser inspection sensor data. It is believed that this method, when applied to solder joint processanalysis, will be superior to existing statistical threshold methods. This method interprets infrared radiation from individual solder joints during and after laser irradiation. Both heat rise and decay are analyzed for each joint. The resulting analog signature can then be compared to other thermal signatures or evaluated using computer analysis. Computer generated thermal models of typical solder joints provided theoretical thermal signatures instrumental in the development of this method. Success has been measured in the detection of small sub-surface solder voids. This paper will provide a general description of the laser inspection process and equipment, a brief history of laser inspection at Litton, a discussion of the signature analysis theory, solder joint thermal modeling and thermal signature analysis results.
Designing a decision support system (DSS) requires two kinds of system analysis. The first kind of analysis defines the decisions that are addressed by the DSS and the models that are used to organize information and ...
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Designing a decision support system (DSS) requires two kinds of system analysis. The first kind of analysis defines the decisions that are addressed by the DSS and the models that are used to organize information and evaluate decision options. The second kind of analysis defines how data and results should be represented, what kinds of operations should be performed on the data, and what kind of control the decision maker should have over the modelingprocess. The author illustrates these two types of analysis in a DSS that provides for the optimization of simulation-based training systems.
A fault detection approach based on the combination of the generalized consistency check and the sequential probability ratio test is developed and applied for validation of signals from process sensors. The basic met...
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A fault detection approach based on the combination of the generalized consistency check and the sequential probability ratio test is developed and applied for validation of signals from process sensors. The basic methodology requires at least triple redundancy of a given measurement from like sensors and analytical measurements. The separate measurement of the signal mean value and the random fluctuation improves the reliability of fault identification and signal reconstruction. The diagnostis of the source of anomaly in a subsystem is performed by multivariate autoregressive modeling of the process signals and the analysis of resulting signatures.
作者：
AnonISA
Research Triangle Park NC USA ISA Research Triangle Park NC USA
This proceedings contains 169 papers by various authors, dealing with advances in instrumentation. Major topics covered are: processcontrol strategies, integrated plant management systems, pipeline pumps/compressor c...
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ISBN:
(纸本)1556170521
This proceedings contains 169 papers by various authors, dealing with advances in instrumentation. Major topics covered are: processcontrol strategies, integrated plant management systems, pipeline pumps/compressor control, tank gauging and storage monitoring;food/pharmaceutical instrumentation control systems;control systems for power plants, pulp and paper industry, waste disposal;water production/distribution automation;computer applications for water/wastewater control;electrochemical analysis, process gas chromatography/IR spectroscopy;modern control technology applications;discrete/batch control and process management;smart field devices;manufacturing automation protocol (MAP);adaptive control applications;control concepts;PC's in manufacturing;computer integrated manufacturing (CIM);programmable logic controller (PLC);database/software integration;human interfaces;fiber optic data communications;artificial intelligence;reason technology;optical analyzer techniques;start-up management;project management;biotechnology instrumentation control;modeling/simulating manufacturing systems;batch control applications;microsoftware environments, broadband networked systems, space telemetry communications, training program development.
An approach is proposed for extracting information from airborne Doppler radar returns that can be used to determine the presence of wind shear in commercial aviation. Issues that are discussed include modeling in ter...
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ISBN:
(纸本)0818608161
An approach is proposed for extracting information from airborne Doppler radar returns that can be used to determine the presence of wind shear in commercial aviation. Issues that are discussed include modeling in terms of stochastic differential equations, estimation in terms of minimum-mean-square-error filters, and detection in terms of a first-passage problem. Some discussion of the hardware architecture needed to process the data in a timely and efficient manner is included.
After adjustment of empirical constants contained within the model of the transient contacting process developed in Part I of this paper, predictions of the duration of transient contact, frequency of contact, local l...
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After adjustment of empirical constants contained within the model of the transient contacting process developed in Part I of this paper, predictions of the duration of transient contact, frequency of contact, local liquid-contact-time fraction, and local liquid-contact-area fraction show good agreement with experimental results for a copper/water system reported in the literature. Extension of the model indicates that for surfaces with poor thermal properties, heat transfer due to transient contact can constitute a major portion of the total heat transfer in the film boiling regime. A comparison of the minimum film boiling condition, developed on the basis of a surface thermal recovery time, shows reasonable agreement with Henry's correlation and also with experimental data reported in the literature for copper and stainless steel surfaces.
This paper discusses the need for developing an automated process for knowledge acquisition. A number of existing knowledge acquisition techniques are discussed. The existing techniques are based on shallow knowledge ...
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This paper discusses the need for developing an automated process for knowledge acquisition. A number of existing knowledge acquisition techniques are discussed. The existing techniques are based on shallow knowledge in terms of production rules. It is shown in this paper that process systems require a more systematic method of analysis, wherein a deep understanding of the physics of the process has to be integrated with heuristic information that needs to be extracted from operators or engineers. The process of modeling deep knowledge is achieved by the goal tree-success tree concept. The heuristic information is extracted from the answers of operators to simple questions made by the computer. The questions addressed to the operator are generated from the deep knowledge of the plant. The MAKE process discussed in this paper models the deep understanding and the heuristic information about a plant.
The problem of on-line control of plastic injection molding machines is considered. The specific problem studied is accurate regulation of melt temperature which has a significant effect on quality of the molded parts...
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The problem of on-line control of plastic injection molding machines is considered. The specific problem studied is accurate regulation of melt temperature which has a significant effect on quality of the molded parts. A robust system identification and control mothodology is developed which uses canonical variates analysis for identification and model predictive control for regulation. data collected from an operating machine are used for identification of control system models in two operating states. Temperature regulation performance is analyzed using simulations in which significant disturbances in machine variables and noise are introduced. The results indicate that the proposed methodology is superior to current PID controllers and can be easily implemented in current digital processcontrol computers.
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