Quality control chart practice involves two distinct phases. Phase I is used for analyzing past data for a lack of control and for assisting in establishing estimates for the process mean and variance when no standard...
Quality control chart practice involves two distinct phases. Phase I is used for analyzing past data for a lack of control and for assisting in establishing estimates for the process mean and variance when no standards are given. In Phase ii the control chart is constructed and used as a process monitoring tool. The current available methodologies for manufacturing processanalysis and control chart design assume either independence between successive observations or correlated measurements within the elements of rational subgroups. In this dissertation, the basic concepts of processanalysis and the methodological procedures for control chart design are expanded to explicitly consider the simultaneous occurrence of correlated structures that invariably exist between subgroups, as well as within subgroups. A space-time modeling approach based on space-time autoregressive-moving average (STARMA) models is used to correctly model manufacturing processes by accommodating for rational subgroups that contain both within and between correlations. This new approach to Phase I analysis, addresses three cases: (i) one quality characteristic, sample size equal to one, (ii) one quality characteristic, size of each subgroup greater than one, and (iii) multiple quality characteristics, sample size greater than one. The design parameters of the Shewhart control chart, namely sample size, control limit width, and frequency of sampling, had previously been determined based either solely on statistical criteria or on economic factors alone. In this dissertation, the existing design methods are enhanced by developing a multiple criteria modeling approach. The enhanced design method minimizes the long run average operating cost per unit time while maximizing the statistical properties that are needed in order to appropriately monitor the process. The optimal control chart design is determined via an optimization code which accounts for the constraint that the frequency of sampling mus
For the analysis and synthesis of discrete-time nonlinear systems and signals, it is essential to use models that are general enough to be accurate, but restrictive enough to be mathematically and computationally prac...
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For the analysis and synthesis of discrete-time nonlinear systems and signals, it is essential to use models that are general enough to be accurate, but restrictive enough to be mathematically and computationally practical. The authors believe that feedback linearizable (FBL) systems provide a good balance between these conflicting goals. The authors define the FBL model and use it to fit the sunspot time series, which shows evidence of being a nonlinear process. Techniques for estimating the FBL parameters are presented and comparisons with various linear and nonlinear models are made.
The field of Artificial Intelligence, especially object-oriented programming (i.e., relational data driven computer science techniques), has opened up a new world to those who are concerned with processmodeling. The ...
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The field of Artificial Intelligence, especially object-oriented programming (i.e., relational data driven computer science techniques), has opened up a new world to those who are concerned with processmodeling. The confines of logic driven computing and traditional algorithms provide severe limits to representation of knowledge and decision methods. Those organizations who must deal with control problems and quality problems often settle for inadequate solutions because of the enormity of the problem or the overwhelming need for nontraditional or expert methods. This paper concerns itself with modelingprocesses with AI techniques and its application within process model development, statistical analysis, statistical control, and dynamic process simulation. The orientation is chemical operations, specifically batch oriented. The audience is control engineers, operations personnel, and process engineers.
A CAD-based optimal planning scheme for a spot welding task in an automobile production line is considered. After extracting the modelingdata from a commercially available CAD system, both collision-free motion plann...
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A CAD-based optimal planning scheme for a spot welding task in an automobile production line is considered. After extracting the modelingdata from a commercially available CAD system, both collision-free motion planning and optimal sequence planning are derived by a modified traveling salesman problem (TSP) algorithm. Graphic simulation and analysis for a set of welding points of an automobile part are used to show that the proposed planning scheme can enhance the efficiency of spot welding robots in the automobile industry.
This paper presents an updated overview of the Computer Aided System Engineering and analysis (CASE/A)-ECLSS series modeling package. CASE/A is an Environmental control and Life Support System (ECLSS) and Active Therm...
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The analysis and interpretation of the outgassing data obtained from Wide Field Planetary Camera (WFPC) components and other sample specimens is a necessary step in the prediction of the instrument's performance a...
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The analysis and interpretation of the outgassing data obtained from Wide Field Planetary Camera (WFPC) components and other sample specimens is a necessary step in the prediction of the instrument's performance and in the process of improving it. The data of the present work, obtained in the Jet Propulsion Laboratory (JPL) Molecular Contamination Investigation Facility (MCIF), includes both the mass accumulation of outgas species as a function of time at three surface temperatures (-20, -50 and -100°C) for sample temperatures of interest and the desorption as a function of time at three (higher) surface temperatures. The process of modeling the data for each sample in terms of a minimum number of species, each characterized by a source rate and activation energy, by a re-emission rate constant during accumulation, and by a desorption rate, emission rate constant, and activation energy, is discussed. These results, which provide guidance as to which WFPC subsystems most significantly limit the instrument's performance, are presented. A technique for the estimation of the source emission time constant, required for the prediction of the utility of a subsystem bakeout, is described. Finally, the development of the first order kinetic constants for the WFPC contamination modeling activity is discussed.
A path analysis approach to concurrent program testing is proposed. A concurrent path model for modeling the execution behavior of a concurrent program is presented. In the model, an execution of a concurrent program ...
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ISBN:
(纸本)0818620307
A path analysis approach to concurrent program testing is proposed. A concurrent path model for modeling the execution behavior of a concurrent program is presented. In the model, an execution of a concurrent program is seen as involving a concurrent path (which comprises the paths of all concurrent tasks), and the tasks' synchronizations are modeled as a concurrent route to traverse the concurrent path involved in the execution. Accordingly, testing is a process to examine the correctness of each concurrent route along all concurrent paths of concurrent programs. On the basis of the model, the test format is defined, and a path analysis testing methodology is presented. Also, several coverage criteria, extended from coverage criteria for sequential programs, are proposed. Some practical issues of path analysis testing, namely, test path generation, test data generation, and design of the test execution control mechanism are also addressed.
This paper describes a prototype integrated environment, the Advanced Satellite Workstation (ASW), that has been developed and delivered for evaluation and operator feedback in an operational satellite control center....
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This paper describes a prototype integrated environment, the Advanced Satellite Workstation (ASW), that has been developed and delivered for evaluation and operator feedback in an operational satellite control center. The current ASW hardware consists of a Sun Workstation and Macintosh ii Workstation connected via an ethernet Network Hardware and Software, Laser Dick System, Optical Storage System, and Telemetry data File Interface. The central mission of ASW is to provide an intelligent decision support and training environment for operator/analysts of complex systems such as satellites. There have been many workstation implementations recently which incorporate graphical telemetry displays and expert systems. ASW is a considerably broader look at intelligent, integrated environments for decision support, based upon the premise that the central features of such an environment are intelligent data access and integrated toolsets. A variety of tools have been constructed in support of this prototype environment including: an automated pass planner for scheduling vehicle support activities, architectural modeler for hierarchical simulation and analysis of satellite vehicle subsystems, multimedia-based information systems that provide an intuitive and easily accessible interface to Orbit Operations Handbooks and other relevant support documentation, and a dataanalysis architecture that integrates user modifiable telemetry display systems, expert systems for background dataanalysis, and interfaces to the multimedia system via inter-process communication.
Knowledge base building environments must progress in two important directions: (i) increased participation of domain experts in the knowledge design process through new computational models and effective man-machine ...
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This Proceedings includes part ii of the papers presented at the conference (29 papers), dealing the dynamics of air pollution, desorption of odor substances from water bodies to the atmosphere, an atmospheric survey ...
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This Proceedings includes part ii of the papers presented at the conference (29 papers), dealing the dynamics of air pollution, desorption of odor substances from water bodies to the atmosphere, an atmospheric survey from Japan, modeling of pollutant diffusion and acid deposition, and other subjects. Some of the latter deal with the following subjects: trends of air quality and atmospheric deposition in Tokyo;influence of ambient temperature on motor vehicle emissions;analysis of gas concentration predictions using monitoring data;reactions of monoterpenes with ozone, sulfur dioxide and nitrogen dioxide;acid rain model development;uncertainty of atmospheric source-receptor relationships in Europe;metals in airborne particulate mattrer in rural Switzerland;nitrogen and major ion deposition in conifer forests in the USA and Germany;aliphatic and carbonyl carbon in Los Angeles aerosols;chemistry of dews and frosts in Indianapolis;reasctive plume model for the NO-NO2-O3 system;hailstones as cloud water composition probes;acid rain and photochemical oxidants control policy in Europe;a design for an occult precipitation collector;removal of gaseous mercury from air using a gold coated denuder.
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