Automated Classification of Bioprocess Based on Optimum Compromise Whitening and Clustering

The proposed methodology of technological state classification is based on data smoothing, dimensionality reduction, compromise whitening, and optimum clustering. The novelty of our approach is in the stabile state hypothesis which improves initialization of c-mean algorithm and enables interleaved cross-validation strategy. We also employ the Akaike information criterion to obtain the optimum number of technological states that minimize it, but using as many as possible clusters and components. The general approach is applied to state classification of Pseudomonas putida fed-batch cultivation on octanoic acid

Novel Micro-scale Analytical Devices for On-line Bioprocess Monitoring: A Review

This review examines the potential of novel micro-scale microfluidic analytical devices – lab-on-a-chip (LOC), micro total analysis systems (µ-TAS) – for on-line monitoring and control of industrial bioprocesses. First, motivation for the current study is presented and potential benefits from the use of micro-scale analytical devices in bioprocess control and monitoring are outlined. This is followed by a review of the state of the art in the relevant application domain (cell analysis) for novel microfluidic analytical devices. Finally, the conclusion provides a summarizing comparison of the main features of the reported micro-scale analytical devices evaluating their potential applicability for on-line bioprocess monitoring, with the most promising concepts identified

Strategies for Automated Control of the Bioproduction of Mcl-PHA Biopolymers

Medium-chain-length polyhydroxyalkanoates (mcl-PHAs) are polyesters synthesized by numerous bacteria as storage material. Despite being promising candidates for biodegradable materials of industrial interest and environmental value, their usage is still rather limited because of high production costs. One of the areas with considerable potential for further improvements is control of the production process. This paper deals with the experimental work related to the design of control strategies for mcl-PHA biopolymer production process (Pseudomonas putida KT2442 fed-batch cultivations). For this bioprocess, a set of five control strategies (two main and three auxiliary strategies) have been proposed, together with the proper sequence of their switching during the fedbatch part of the production process. The application of these strategies with octanoic acid as a sole carbon source resulted in intracellular PHA content (max. mass fraction 65 % of mcl-PHA in cell dry mass (g g–1) and PHA productivity (max. 0.89 g L–1 h–1) comparable to the best results reported in the literature for this type of strain and carbon substrate. This work is licensed under a Creative Commons Attribution 4.0 International License

Adaptive Control of Saccharomyces cerevisiae Yeasts Fed-Batch Cultivations

In this paper, the application of an adaptive algorithm for control of fed-batch bioprocess capable of coping with time-variant process properties in the presence of uncertainties is introduced. The proposed adaptive controller uses Maršík’s heuristic algorithm for adaptation based on control error oscillation rate criterion without the need of a mathematical model of the controlled process or any special test signals. The intended application of the resulting controller was off-gas CO2 concentration control in fed-batch yeast cultivations where the set point has the form of a time-varying concentration profile. The controller has been tested in a series of experimental fed-batch cultivations with D7 Saccharomyces cerevisiae strain, a UV mutant suitable for ergosterol production, in 7‑litre laboratory bioreactor. Obtained results demonstrate good properties of this adaptive controller that can be used without the need for a tedious parameter identification of the complex bioprocess

Fracture mechanics description of the defect in rolling cylinder

project m- IPMinfra (CZ.02.1.01/0.0/0.0/16_013/0001823

Adaptive Control of Saccharomyces cerevisiae Yeasts Fed-Batch Cultivations

In this paper, the application of an adaptive algorithm for control of fed-batch bioprocess capable of coping with time-variant process properties in the presence of uncertainties is introduced. The proposed adaptive controller uses Maršík’s heuristic algorithm for adaptation based on control error oscillation rate criterion without the need of a mathematical model of the controlled process or any special test signals. The intended application of the resulting controller was off-gas CO2 concentration control in fed-batch yeast cultivations where the set point has the form of a time-varying concentration profile. The controller has been tested in a series of experimental fed-batch cultivations with D7 Saccharomyces cerevisiae strain, a UV mutant suitable for ergosterol production, in 7‑litre laboratory bioreactor. Obtained results demonstrate good properties of this adaptive controller that can be used without the need for a tedious parameter identification of the complex bioprocess

Numerical simulation of a cylindrical fatigue specimen loaded under mixed-mode conditions

This research has been supported by the Ministry of Education, Youth and Sports of the Czech Republic under the project m-IPMinfra (CZ.02.1.01/0.0/0.0/16_013/0001823) and the equipment and the base of research infrastructure IPMinfra were used during the research activities. Also, thanks are due to the specific research project FSI-S-17-4386 of the Faculty of Mechanical Engineering, BUT.Although a significant number of service failures occur due to the fatigue crack propagation under mixed-mode loading conditions, this area is still relatively unexplored. That is why study of mixed mode fatigue crack propagation has become much more relevant recently. The mixed mode crack behaviour is also the subject of this paper. It is focused mainly on numerical modelling of cylindrical fatigue specimen containing small cracks, loaded under mixed mode conditions. The simulation results are needed to successfully evaluate experimental measurements of crack propagation in the cylindrical fatigue specimens made of the austenitic stainless steel 316L. Some of the experimental data are also presented in this paper. Comparison of mixed mode results and pure mode I data is also carried out. Fig. 1