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Real Processes (real + process)
Selected AbstractsSimultaneous Data Reconciliation and Parameter Estimation in Bulk Polypropylene Polymerizations in Real TimeMACROMOLECULAR SYMPOSIA, Issue 1 2006Diego Martinez Prata Abstract This work presents the implementation of a methodology for dynamic data reconciliation and simultaneous estimation of quality and productivity parameters in real time, using data from an industrial bulk Ziegler-Natta propylene polymerization process. A phenomenological model of the real process, based on mass and energy balances, was developed and implemented for interpretation of actual plant data. The resulting nonlinear dynamic optimization problem was solved using a sequential approach on a time window specifically tuned for the studied process. Despite the essentially isothermal operation conditions, obtained results show that inclusion of energy balance constraints allows for increase of information redundancy and, as a consequence, for computation of better parameter estimates than the ones obtained when the energy balance constraints are not considered (Prata et al., 2005). Examples indicate that the proposed technique can be used very effectively for monitoring of polymer quality and identification of process malfunctions in real time even when laboratory analyses are scarce. [source] Asymptotic analysis of flow in wavy tubes and simulation of the extrusion processMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 8 2007A. Ainser Abstract The paper is devoted to the mathematical modelling of an extrusion process. Usually, an extruder has a very complicated geometry. This generates a lot of difficulties for computations of three-dimensional flows. In the present paper, we develop and justify the asymptotic domain decomposition strategy in order to parallelize the computational process and reduce the memory. The error estimates are proved for the Stokes steady-state equation in the two-dimensional and three-dimensional cases. Then, the asymptotic domain decomposition procedure is applied for numerical testing and computations of the non-Newtonian fluid simulating a real process of the polymer extrusion. Copyright © 2007 John Wiley & Sons, Ltd. [source] Plant diagnostics by transient classification: The ALADDIN approachINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2002Davide Roverso Any action taken on a plant, for example in response to an abnormal situation or in reaction to unsafe conditions, relies on the ability to identify the state and dynamics of operation of the plant. Although there might be hundreds or even thousands of measurements in a plant, there are generally few events occurring. The data from these measurements must be mapped into appropriate descriptions of the occurring event(s), which in most cases is a difficult task. The real-time history of scores of variables can be displayed and monitored in most computerized plant monitoring and control systems. However, whereas a simple visual inspection of displayed trends is generally sufficient to allow the operator to confirm the plant status during normal, steady-state operations, when the plant is subject to deviations due to anomalies or faults, the displayed trends of interacting variables can be very difficult to interpret, either because the changes are too subtle, or because the changes are too fast. In this article we describe the ALADDIN methodology for dynamic event recognition and fault diagnosis, which combines techniques such as recurrent neural network ensembles, wavelet on-line pre-processing (WOLP), and autonomous recursive task decomposition (ARTD), in an attempt to improve the practical applicability and scalability of this type of system to real processes and machinery. © 2002 Wiley Periodicals, Inc. [source] Vygotsky's Non-classical Dialectical MetapsychologyJOURNAL FOR THE THEORY OF SOCIAL BEHAVIOUR, Issue 3 2003Dorothy Robbins The approach taken here is to begin to understand the focus from abstract to concrete in learning to master the principles of methodology, which are different from Western methods and procedures. This methodology is opposed to the empiricist approach of establishing rules and procedures from the concrete to the abstract. The initial discussion revolves around an explanation of the use of metaphor, metatheory, and psychology understood as a non-classical science. There is then a discussion on dialectics, dialectical synthesis, and metafacts. The core of the article is dedicated to a metatheoretical description Vygotsky uses as an abstract outline of possible guidelines in better understanding how to implement a model for non-classical psychology, using the example of a table being reflected in a mirror. A represents the actual table, while a represents the object being reflected in the mirror, and X represents the processes that take place in the mirror (i.e., the reflection of a table is the refraction of light beams). Therefore, Vygotsky concludes that both A and X are real processes and that a is their apparent, i.e., unreal result. The reflection does not exist, but both the table and the light exist. The result is that the objective existence of X and A independent of a is a dogma of materialistic psychology. There is a discussion on the interfunctional relationships of importance in such a model, and the role of consciousness, and language. The focus of this metatheoretical framework supports Vygotsky's intentions of reaching individual inner freedom and freedom of action, together with Spinoza's social determinism. [source] Information and communication technology for process management in healthcare: a contribution to change the culture of blameJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 6-7 2010Silvana Quaglini Abstract Statistics on medical errors and their consequences has astonished, during the previous years, both healthcare professionals and ordinary people. Mass-media are becoming more and more sensitive to medical malpractices. This paper elaborates on the well-known resistance of the medical world to disclose actions and processes that could have caused some damages; it illustrates the possible causes of medical errors and, for some of them, it suggests solutions based on information and communication technology. In particular, careflow management systems and process mining techniques are proposed as a means to improve the healthcare delivery process: the former by facilitating task assignments and resource management, the latter by discovering not only individuals' errors, but also the chains of responsibilities concurring to produce errors in a complex patient's pathway. Both supervised and unsupervised process mining will be addressed. The former compares real processes with a known process model (e.g., a clinical practice guideline or a medical protocol), whereas the latter mines processes from raw data, without imposing any model. The potentiality of these techniques is illustrated by means of examples from stroke patient management. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||