Search results for "Process Control"
showing 10 items of 76 documents
Wine Fermentation
2019
Currently wineries are facing new challenges due to actual market demands for creation of products exhibiting more individual flavors[...]
Stable layer-building strategy to enhance cold-spray-based additive manufacturing
2020
Abstract Cold spray (CS) has recently become one of the popular additive manufacturing (AM) processes for its advantages: high-forming efficiency, low temperature, and no phase changing of materials. These advantages may make CS able to form large volume objects and possibly directly iterate with material-removing processes to become a hybrid AM process. Current research proposes using a bulk-based volume-forming strategy (e.g. a tessellation-based method) for volume building. Although it can form 3D volumes, the control of the process is difficult and it has limitations in forming complex 3D near-net-shapes with acceptable accuracy. This also conflicts with the basic principle of AM, where…
Novel, automated, semi-industrial modular photobioreactor system for cultivation of demanding microalgae that produce fine chemicals - The next story…
2021
Abstract Recently, there has been increased interest in the use of microorganisms in the production of pharmaceuticals, nutraceuticals and energy supply products, which is due to their rapid growth rate and ability to biosynthesize fine chemicals or biotransform specific xenobiotics. To achieve the desired scale of production and optimization of microbial cultures, it is necessary to design bioreactors that enable process automation, control of working parameters, reduction of microbial and chemical contaminations, and culture independence of climate conditions. In response to this need, an original, modular airlift-type photobioreactor system was designed and manufactured. This novel semit…
Building a statistical surveillance dashboard for COVID-19 infection worldwide
2020
When a pandemic like the current novel coronavirus (COVID-19) breaks out, it is important that authorities, healthcare organizations and official decision makers, have in place an effective monitoring system to promptly analyze data, create new insights into problematic areas and generate actionable knowledge for fact-based decision making. The aim of this article is to describe an initial work focused on building a comprehensive statistical surveillance dashboard for the epidemic of COVID-19, which can be exploited also for future needs. We propose novel ways of exploring, analyzing and presenting data, using metrics that have not been used previously. We also show the steps necessary to b…
A context-aware approach for long-term behavioural change detection and abnormality prediction in ambient assisted living
2015
This research aims to describe pattern recognition models for detecting behavioural and health-related changes in a patient who is monitored continuously in an assisted living environment. The early anticipation of anomalies can improve the rate of disease prevention. Here we present different learning techniques for predicting abnormalities and behavioural trends in various user contexts. In this paper we described a Hidden Markov Model based approach for detecting abnormalities in daily activities, a process of identifying irregularity in routine behaviours from statistical histories and an exponential smoothing technique to predict future changes in various vital signs. The outcomes of t…
Fuzzy control of pH using NAL
1991
Abstract A fuzzy controller for a neutralization process is described. The controller was set up for a laboratory pilot plant. The approach is shown to be effective and can be extended to highly nonlinear and nonstationary processes. The “operator” knowledge encoded in the rules was obtained by several experimental runs of the system using manual control. Rules are composed using the max-min compositional rule of inference. The use of metarules, which depends on controller performance and on active disturbances, makes the controller behave like an adaptive controller. The control program is encoded in NAL, a new experimental logic programming language that was first used in this work in a r…
Type-2 Fuzzy Control of a Bioreactor
2009
Abstract—In this paper the control of a bioprocess using an adaptive type-2 fuzzy logic controller is proposed. The process is concerned with the aerobic alcoholic fermentation for the growth of Saccharomyces Cerevisiae a n d i s characterized by nonlinearity and parameter uncertainty. Three type-2 fuzzy controllers heve been developed and tested by simulation: a simple type-2 fuzzy logic controller with 49 rules; a type-2 fuzzyneuro- predictive controller (T2FNPC); a t y p e -2 selftuning fuzzy controller ( T2STFC). The T2FNPC combines the capability of the type-2 fuzzy logic to handle uncertainties, with the ability of predictive control to predict future plant performance making use of a…
Multivariate quality control studies applied to Ca(II) and Mg(II) determination by a portable method
1998
Made available in DSpace on 2022-04-28T19:53:14Z (GMT). No. of bitstreams: 0 Previous issue date: 1998-01-01 A portable or field test method for simultaneous spectrophotometric determination of calcium and magnesium in water using multivariate partial least squares (PLS) calibration methods is proposed. The method is based on the reaction between the analytes and methylthymol blue at pH 11. The spectral information was used as the X-block and the Ca(II) and Mg(II) concentrations obtained by a reference technique (ICP-AES) were used as the Y-block. Two series of analyses were performed, with a month's difference between them. The first series was used as the calibration set and the second on…
Uncertainty-Based Internal Quality Control. Harmonization Considerations
2006
Three main quality aspects for analytical laboratories are internal method validation, internal quality control (IQC), and sample result uncertainty. Unfortunately, in the past they have been used in a nonharmonized way. The most universal IQC tool is the mean chart, but some criteria used to fix their control limits do not fit the real nature of analytical results. A new approach for fixing these limits is proposed (the u-approach). The key is the combined uncertainty, u, obtained from the method validation information, also used for estimating the sample result uncertainty. A comparative study on "in-control" simulated, bibliographic, and real laboratory data suggests that the u-approach …
Temperature imaging and image processing in the steel industry
1996
Our aim is twofold: to present our temperature measurement system based on CCD technology, which gives a linear response versus temperature, and to display two industrial applications in which our system has been involved to optimize and characterize the process. We present a short summary dealing with temperature evaluations from radiation measurements. We consider especially the problems of the surroundings, the atmosphere, and the emissivity assumption. After selecting a value for the emissivity, we show that the use of the CCD technology enables us to obtain high spatial and temporal resolution temperature imaging, and provides further information, mainly a linear response versus temper…