Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 43 (1997), S. 986-996 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Efficient algorithms were developed for estimating model parameters from measured data, even in the presence of gross errors. In addition to point estimates of parameters, however, assessments of uncertainty are needed. Linear approximations provide standard errors, but they can be misleading when applied to models that are substantially nonlinear. To overcome this difficulty, profiling methods were developed for the case in which the regressor variables are error free. These methods provide accurate nonlinear confidence regions, but become expensive for a large number of parameters. These profiling methods are modified to error-in-variable-measurement models with many incidental parameters. Laplace's method is used to integrate out the incidental parameters associated with the measurement errors, and then profiling methods are applied to obtain approximate confidence contours for the parameters. This approach is computationally efficient, requires few function evaluations, and can be applied to large-scale problems. It is useful when certain measurement errors (such as input variables) are relatively small, but not so small that they can be ignored.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 42 (1996), S. 2841-2856 
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Gross-error detection plays a vital role in parameter estimation and data reconciliation for dynamic and steady-state systems. Data errors due to miscalibrated or faulty sensors or just random events nonrepresentative of the underlying statistical distribution can induce heavy biases in parameter estimates and reconciled data. Robust estimators and exploratory statistical methods for the detection of gross errors as the data reconciliation is performed are discussed. These methods have the property insensitive to departures from ideal statistical distributions and to the presence of outliers. Once the regression is done, the outliers can be detected readily by using exploratory statistical techniques. Optimization algorithm and reconciled data offer the ability to classify variables according to their observability and redundancy properties. Here an observable variable is an unmeasured quantity that can be estimated from the measured variables through the physical model, while a nonredundant variable is a measured variable that cannot be estimated other than through its measurement. Variable classification can be used to help design instrumentation schemes. An efficient method for this classification of dynamic systems is developed. Variable classification and gross-error detection have important connections, and gross-error detection on nonredundant variables has to be performed with caution.
    Additional Material: 26 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...