scholarly journals Subspace Based Model Identification for an Industrial Bioreactor: Handling Infrequent Sampling Using Missing Data Algorithms

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1686
Author(s):  
Nikesh Patel ◽  
Brandon Corbett ◽  
Johan Trygg ◽  
Chris McCready ◽  
Prashant Mhaskar

This manuscript addresses the problem of modeling an industrial (Sartorius) bioreactor using process data. In the context of the Sartorius Bioreactor, it is important to appropriately address the problem of dealing with a large number of variables, which are not always measured or are measured at different sampling rates, without taking recourse to simpler interpolation- or imputation-based approaches. To this end, a dynamic model for the Sartorius Bioreactor is developed via appropriately adapting a recently presented subspace model identification technique, which in turn uses nonlinear iterative partial least squares (NIPALS) algorithms to gracefully handle the missing data. The other key contribution is evaluating the ability of the identification approach to provide insight into the process by computing interpretable variables such as metabolite rates. The results demonstrate the ability of the proposed approach to model data from the Sartorius Bioreactor.

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1691
Author(s):  
Nikesh Patel ◽  
Kavitha Sivanathan ◽  
Prashant Mhaskar

This paper addresses the problem of quality modeling in polymethyl methacrylate (PMMA) production. The key challenge is handling the large amounts of missing quality measurements in each batch due to the time and cost sensitive nature of the measurements. To this end, a missing data subspace algorithm that adapts nonlinear iterative partial least squares (NIPALS) algorithms from both partial least squares (PLS) and principal component analysis (PCA) is utilized to build a data driven dynamic model. The use of NIPALS algorithms allows for the correlation structure of the input–output data to minimize the impact of the large amounts of missing quality measurements. These techniques are utilized in a simulated case study to successfully model the PMMA process in particular, and demonstrate the efficacy of the algorithm to handle the quality prediction problem in general.


2012 ◽  
Vol 503-504 ◽  
pp. 1357-1359
Author(s):  
Qiang Wu ◽  
Hao Xiong ◽  
Guang Wei Meng ◽  
Li Bing Zhou

This paper applies identification technique to the marine electric propulsion system analysis, adopts the recursive extended least squares (RELS) algorithm to estimate the structure and parameters of the model, employs the variable forgetting factors into the algorithm to improve the tracking characteristic of the parameters, establishes the dynamic model of a simulated electric propulsion unit under the excitation control based on the experiment data, and finally verifies the validity of the method through the consistency between simulation result and experimental result.


Author(s):  
M.A. Reshitko ◽  
◽  
A.B. Usov

. In this paper we consider the hierarchical two-level dynamic model of water consumption of enterprises of Rostov region. On the top level there is region’s government (supervisor) and on the lower level there are enterprises grouped by the types of economic activity. Such grouping allows one to avoid modelling all region’s enterprises which consumes water (there were about 500 enterprises in 2019) while still considering the uniqueness of the enterprises. We consider three groups of enterprises which, according to statistics, are the main water consumers. The enterprises aim to maximize their production while supervisor seeks to minimize water consumption and to maximize production. We introduce generalized goal function for supervisor, which it seeks to maximize depending on what it values the most – production or water consumption. Using the model, we study how supervisor is able to control water consumption of the enterprises with extra fees and how it may affect production level. We provide algorithms for model identification and study. For model identification we use least squares method and the data from publicly available sources. To study model we use Pontryagin’s maximum principle and quality representative scenarios method. We provide various calculations for the model with different supervisor’s preferences. We show that it is possible to reduce water consumption by more than 50 % with production decrease being less than 25%


Author(s):  
Stefan Scherbaum ◽  
Simon Frisch ◽  
Maja Dshemuchadse

Abstract. Folk wisdom tells us that additional time to make a decision helps us to refrain from the first impulse to take the bird in the hand. However, the question why the time to decide plays an important role is still unanswered. Here we distinguish two explanations, one based on a bias in value accumulation that has to be overcome with time, the other based on cognitive control processes that need time to set in. In an intertemporal decision task, we use mouse tracking to study participants’ responses to options’ values and delays which were presented sequentially. We find that the information about options’ delays does indeed lead to an immediate bias that is controlled afterwards, matching the prediction of control processes needed to counter initial impulses. Hence, by using a dynamic measure, we provide insight into the processes underlying short-term oriented choices in intertemporal decision making.


2011 ◽  
Vol 29 (supplement) ◽  
pp. 283-304 ◽  
Author(s):  
Timothy R. Brick ◽  
Steven M. Boker

Among the qualities that distinguish dance from other types of human behavior and interaction are the creation and breaking of synchrony and symmetry. The combination of symmetry and synchrony can provide complex interactions. For example, two dancers might make very different movements, slowing each time the other sped up: a mirror symmetry of velocity. Examining patterns of synchrony and symmetry can provide insight into both the artistic nature of the dance, and the nature of the perceptions and responses of the dancers. However, such complex symmetries are often difficult to quantify. This paper presents three methods – Generalized Local Linear Approximation, Time-lagged Autocorrelation, and Windowed Cross-correlation – for the exploration of symmetry and synchrony in motion-capture data as is it applied to dance and illustrate these with examples from a study of free-form dance. Combined, these techniques provide powerful tools for the examination of the structure of symmetry and synchrony in dance.


2020 ◽  
Vol 151 (1) ◽  
pp. 96-126
Author(s):  
Kathryn Crim
Keyword(s):  
The One ◽  

Karl Marx’s comments on silk manufacture in “The Working Day” chapter of Capital, volume 1, demonstrate how “quality”—usually associated with “use value”—has been mobilized by capital to naturalize industrialized labor. Putting his insight into conversation with a recent multimedia poetic project, Jen Bervin’s Silk Poems (2016–17), this essay examines the homology between, on the one hand, poetry’s avowed task of fitting form to content and, on the other, the ideology of labor that fits specific bodies to certain materials and tasks.


Author(s):  
Viola Kita

Raymond Carver’s work provides the opportunity for a spiritual reading. The article that offers the greatest insight into spirituality is William Stull’s “Beyond Hopelessville: Another Side of Raymond Carver.” In it we can notice the darkness which is dominant in Carver’s early works with the optimism that is an essential part of Carver’s work “Cathedral”. A careful reading of “A Small Good Thing” and “The Bath” can give the idea that they are based on the allegory of spiritual rebirth which can be interpreted as a “symbol of Resurrection”. Despite Stull’s insisting in Carver’s stories allusions based on the Bible, it cannot be proved that the writer has made use of Christian imagery. Therefore, it can be concluded that spirituality in Carver’s work is one of the most confusing topics so far in the literary world because on one hand literary critics find a lot of biblical elements and on the other hand Carver himself refuses to be analyzed as a Christian writer.


2018 ◽  
Vol 1 (1) ◽  
pp. 18
Author(s):  
Kym Maclaren

“To consent to love or be loved,” said Merleau-Ponty, “is to consent also to influence someone else, to decide to a certain extent on behalf of the other.” This essay explicates that idea through a meditation on intimacy. I propose, first, that, on Merleau-Ponty’s account, we are always transgressing into each other’s experience, whether we are strangers or familiars; I call this “ontological intimacy.” Concrete experiences of intimacy are based upon this ontological intimacy, and can take place at two levels: (1) at-this-moment (such that we can experience intimacy even with strangers, by sharing a momentary but extra-ordinary mutual recognition) and (2) in shared interpersonal institutions, or habitual, enduring, and co-enacted visions of who we are, how to live, and what matters. Through particular examples of dynamics within these layers of intimacy (drawing upon work by Berne and by Russon), I claim that we are always, inevitably, imposing an “unfreedom” upon our intimate others. Freedom, then, can only develop from within and by virtue of this “unfreedom.” Thus, what distinguishes empowering or emancipating relationships from oppressive ones is not the removal of transgressive normative social forces; it is rather the particular character of those transgressive forces. Some transgressions upon others’ experience—some forms of “unfreedom”—will tend to promote freedom; others will tend to hinder it. This amounts to a call for promoting agency and freedom not only through critical analysis of public institutions, practices and discourses, but also through critical insight into and transformation of our most private and intimate relationships.


Author(s):  
Zoran Vrucinic

The future of medicine belongs to immunology and alergology. I tried to not be too wide in description, but on the other hand to mention the most important concepts of alergology to make access to these diseases more understandable, logical and more useful for our patients, that without complex pathophysiology and mechanism of immune reaction,we gain some basic insight into immunological principles. The name allergy to medicine was introduced by Pirquet in 1906, and is of Greek origin (allos-other + ergon-act; different reaction), essentially representing the reaction of an organism to a substance that has already been in contact with it, and manifested as a specific response thatmanifests as either a heightened reaction, a hypersensitivity, or as a reduced reaction immunity. Synonyms for hypersensitivity are: altered reactivity, reaction, hypersensitivity. The word sensitization comes from the Latin (sensibilitas, atis, f.), which means sensibility,sensitivity, and has retained that meaning in medical vocabulary, while in immunology and allergology this term implies the creation of hypersensitivity to an antigen. Antigen comes from the Greek words, anti-anti + genos-genus, the opposite, anti-substance substance that causes the body to produce antibodies.


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