Search results for "Process control"
showing 6 items of 76 documents
Chaos and its Degradation-Promoting-Based Control in an Antithetic Integral Feedback Circuit
2022
This letter deals with a novel variant of antithetic integral feedback controller (AIFC) motifs which can feature robust perfect adaptation, a pervasive (desired) ability in natural (synthetic) biomolecular circuits, when coupled with a wide class of process networks to be regulated. Using the separation of timescales in the proposed kind of AIFC, here we find a reducedorder controller that captures the governing slow part of the original solutions under suitable assumptions. Inspired by R(ossler systems, we then make use of such a simpler controller to show that the antithetic circuit can exhibit chaotic behaviors with strange attractors, where the bifurcation from a homeostatic state to c…
Controlling the atmosphere in the malaxation machine headspace in order to improve the quality of Sicilian extra virgin olive oils
2012
During the mechanical extraction process of Virgin Olive Oil (VOO) some important physical phenomena and enzymatic transformations occur influencing the final product quality. The control of process parameters is crucial to ensure the quality of VOO, therefore process monitoring and control is a fundamental requirement in the modern VOO processing industry. The present work proposes a research performed in order to develop a system for the oxygen continuous monitoring inside the malaxation machine to enhance the Sicilian extra virgin olive oil typicality and to establish a correlation with the quality of the final product. The results showed that the use of oxygen during malaxation, allowed…
Pareto frontier in economic-statistical design of a dynamic c chart
2015
The present paper proposes an economic-statistical multi-objective design procedure for a dynamic c control chart. In detail, a mixed integer non-linear constrained mathematical model is formulated to solve the treated problem, whereas the Pareto frontier is described by the ε-constraint method. To show the employment of the proposed procedure a numerical case is solved and the related considerations are given.
A Multi-Objective Design Approach for the c Chart Considering Taguchi Loss Function
2014
The present paper proposes a multi-objective design approach for the c chart, considering in the optimization process of the chart parameters both the statistical and the economic objectives. In particular, the minimization of the hourly total quality related costs is the considered objective to carry out the economic goal, whereas the statistical objective is reached by the minimization the out-of-control average run length of the chart. A mixed integer non-linear constrained mathematical model is formulated to solve the treated multi-objective optimization problem, whereas the Pareto optimal frontier is described by the «-constraint method. In order to show the employment of the proposed …
Acoustic detection and classification of river boats
2011
We present a robust algorithm to detect the arrival of a boat of a certain type when other background noises are present. It is done via the analysis of its acoustic signature against an existing database of recorded and processed acoustic signals. We characterize the signals by the distribution of their energies among blocks of wavelet packet coefficients. To derive the acoustic signature of the boat of interest, we use the Best Discriminant Basis method. The decision is made by combining the answers from the Linear Discriminant Analysis (LDA) classifier and from the Classification and Regression Trees (CART) that is also accompanied with an additional unit, called Aisles, that reduces fal…
Seeking Technical Debt in Critical Software Development Projects : An Exploratory Field Study
2016
In recent years, the metaphor of technical debt has received considerable attention, especially from the agile community. Still, despite the fact that agile practices are increasingly used in critical domains, to the best of our knowledge, there are no studies investigating the occurrence of technical debt in critical software development projects. The results of an exploratory field study conducted across several projects reveal that a variety of business and environmental factors cause the occurrence of technical debt in critical domains. Using Grounded Theory method, these factors are categorized as ambiguity of requirement, diversity of projects, inadequate knowledge management, and res…