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Monitoring Procedures (monitoring + procedure)
Selected AbstractsA Hybrid SPC Method with the Chi-Square Distance Monitoring Procedure for Large-scale, Complex Process DataQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 4 2006Nong Ye Abstract Standard multivariate statistical process control (SPC) techniques, such as Hotelling's T2, cannot easily handle large-scale, complex process data and often fail to detect out-of-control anomalies for such data. We develop a computationally efficient and scalable Chi-Square () Distance Monitoring (CSDM) procedure for monitoring large-scale, complex process data to detect out-of-control anomalies, and test the performance of the CSDM procedure using various kinds of process data involving uncorrelated, correlated, auto-correlated, normally distributed, and non-normally distributed data variables. Based on advantages and disadvantages of the CSDM procedure in comparison with Hotelling's T2 for various kinds of process data, we design a hybrid SPC method with the CSDM procedure for monitoring large-scale, complex process data. Copyright © 2005 John Wiley & Sons, Ltd. [source] Integration of colour and textural information in multivariate image analysis: defect detection and classification issuesJOURNAL OF CHEMOMETRICS, Issue 1-2 2007J. M. Prats-Montalbán Abstract In industrial processes, the detection and visualisation of defects and the development of efficient automated classification tools are strategic issues, especially when dealing with random colour textures (RCTs). This paper discusses the benefits of integrating colour and spatial (i.e. textural) information of digital RGB colour images in multivariate image analysis (MIA) to deal with these topics. Regarding the first one, a simple and computational cost-effective monitoring procedure based on colour-textural MIA merged with multivariate statistical process control (MSPC) ideas is outlined. Two novel computed images: T2 and RSS Images are proposed. The procedure is applied on digital RGB colour images from artificial stone plates. With respect to the second issue, when colour-textural MIA is used for image classification a lot of factors (e.g. pre-processing, modelling,,,) likely affecting the success rate in the classification (SRC) show up. This paper presents a methodology based on the combination of experimental design and logistic regression for choosing the best combination of factors to maximise the SRC of different types of images. Digital RGB colour images from ceramic tiles and orange fruits are used to illustrate the potential of the proposed methodology. Copyright © 2007 John Wiley & Sons, Ltd. [source] Monitoring of batch processes through state-space modelsAICHE JOURNAL, Issue 6 2004Jay H. Lee Abstract The development of a state-space framework for monitoring batch processes that can complement the existing multivariate monitoring methods is presented. A subspace identification method will be used to extract the dynamic and batch-to-batch trends of the process and quality variables from historical operation data in the form of a "lifted" state-space stochastic model. A simple monitoring procedure can be formed around the state and residuals of the model using appropriate scalar statistical metrics. The proposed state-space monitoring framework complements the existing multivariate methods like the multi-way PCA method, in that it allows us to build a more complete statistical representation of batch operations and use it with incoming measurements for early detection of not only large, abrupt changes but also subtle changes. In particular, it is shown to be effective for detecting changes in the batch-to-batch correlation structure, slow drifts, and mean shifts. Such information can be useful in adapting the prediction model for batch-to-batch control. The framework allows for the use of on-line process measurements and/or off-line quality measurements. When both types of measurements are used in model building, one can also use the model to predict the quality variables based on incoming on-line measurements and quality measurements of previous batches. © 2004 American Institute of Chemical Engineers AIChE J, 50: 1198,1210, 2004 [source] An analysis of Taguchi's on-line quality monitoring procedure for attributes with diagnosis errorsAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 3 2001Wagner Borges Abstract The on-line quality monitoring procedure for attributes proposed by Taguchi, Elsayed and Hsiang for processes in which the fraction defective shifts from 0 at some point are examined under the assumption of diagnosis errors. The renewal reward (economic) approach of Nayebpour and Woodall is used to develop a mathematical expression for the long-run expected cost per item produced and assessment of the optimum inspection interval is discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source] The derivation of scientific guidelines for best environmental practice for the monitoring and regulation of marine aquaculture in EuropeJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2001The MARAQUA concerted action (Monitoring and Regulation of Marine Aquaculture) aimed to establish scientific guidelines for best environmental practice for the regulation and monitoring of marine aquaculture throughout the European Union. This paper focuses on the specific objectives of the MARAQUA concerted action and describes the processes adopted by the partnership when reviewing current practice in Europe in relation to licensing, regulatory and monitoring procedures. The paper also summarizes the findings of five topic groups established to analyse the scientific and socio-economic basis of current environmental practice in marine aquaculture and identifies the key recommendations for best environmental practice in relation to marine aquaculture. [source] On the applicability of two different stimulation techniques for intra-operative peroneal nerve conduction testingJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2001W. Nebelung Dysfunction of the peroneal nerve is an important complication of knee surgery. We compared two monitoring procedures of peroneal nerve function during a standardized operation, a closing wedge high tibial osteotomy. For two types of stimulation the evoked compound motor unit action potentials (CMAPs) were recorded on the tibialis anterior muscle. We used direct perineural electrical stimulation of the common peroneal nerve distal to the cuff (dCMAPs) after nerve identification in the surgical field. Additionally, magnetic stimulation of the sacral plexus proximal to the cuff (pCMAPs) was performed. It was found that dCMAPs were recorded during almost one hour of tourniquet time whereas the pCMAPs were blocked after 25,30 min in 9 out of 11 cases. On the other hand, the CMAP obtained after proximal stimulation exhibited a latency shift with tourniquet yielding an indicator of ischaemic changes present beneath and distal to the tourniquet cuff. In conclusion, different applicabilities of both stimulation techniques under tourniquet conditions were demonstrated. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Monitoring processes with data censored owing to competing risks by using exponentially weighted moving average control chartsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 3 2001Stefan H. Steiner In industry, process monitoring is widely employed to detect process changes rapidly. However, in some industrial applications observations are censored. For example, when testing breaking strengths and failure times often a limited stress test is performed. With censored observations, a direct application of traditional monitoring procedures is not appropriate. When the censoring occurs due to competing risks, we propose a control chart based on conditional expected values to detect changes in the mean strength. To protect against possible confounding caused by changes in the mean of the censoring mechanism we also suggest a similar chart to detect changes in the mean censoring level. We provide an example of monitoring bond strength to illustrate the application of this methodology. [source] WATCHING THE DETECTIVES: SEASONAL STUDENT EMPLOYEE REACTIONS TO ELECTRONIC MONITORING WITH AND WITHOUT ADVANCE NOTIFICATIONPERSONNEL PSYCHOLOGY, Issue 2 2002AUDRA D. HOVORKA-MEAD The present paper tested procedural justice hypotheses about seasonal high school and college student employees' reactions to electronic monitoring with video cameras. Study 1, a field study, explored (a) whether employees receiving advance notification of monitoring offered more favorable justice judgments than employees who did not, and (b) whether employees who saw monitoring procedures and/or consequences as fair returned to the organization the following summer. Results supported the hypotheses: employees viewed monitoring procedures as fairer if they received advance notice. Fairness judgments predicted reemployment Study 2, a scenario-based laboratory experiment, also found that advance notice elicited greater justice beliefs. In addition, Study 2 examined how variations in justification for the monitoring affected justice beliefs. Either strong or weak justifications produced greater procedural justice beliefs than no justification. [source] High-resolution biomarker discovery: Moving from large-scale proteome profiling to quantitative validation of lead candidatesPROTEOMICS - CLINICAL APPLICATIONS, Issue 10-11 2008Johannes A. Hewel Abstract Diverse proteomic techniques based on protein MS have been introduced to systematically characterize protein perturbations associated with disease. Progress in clinical proteomics is essential for personalized medicine, wherein treatments will be tailored to individual needs based on patient stratification using noninvasive disease monitoring procedures to reveal the most appropriate therapeutic targets. However, breakthroughs await the successful development and application of a robust proteomic pipeline capable of identifying and rigorously assessing the relevance of multiple candidate proteins as informative diagnostic and prognostic indicators or suitable drug targets involved in a pathological process. While steady progress has been made toward more comprehensive proteome profiling, the emphasis must now shift from in depth screening of reference samples to stringent quantitative validation of selected lead candidates in a broader clinical context. Here, we present an overview of the emerging proteomic strategies for high-throughput protein detection focused primarily on targeted MS/MS as the basis for biomarker verification in large clinical cohorts. We discuss the conceptual promise and practical pitfalls of these methods in terms of achieving higher dynamic range, higher throughput, and more reliable quantification, highlighting research avenues that merit additional inquiry. [source] | ||||||||||||||||