Auch die Mitbestimmung, wie sie heute in Deutschland, aber auch in anderen europäischen Ländern in verschiedenen Formen praktiziert wird, trägt erheblich dazu bei, dass soziale Konflikte auch in der ...Arbeitswelt zivil, rational und kooperativ ausgetragen werden können. Konflikte zwischen den neu entstandenen »Klassen«, dem industriellen Bürgertum und der Arbeiterschaft, die mit der Entstehung des modernen Kapitalismus untrennbar verbundenen sind. Bereits während der deutschen Revolution 1848/49 kursierten erste Ansätze der Mitbestimmung in der Arbeiterschaft. Zum einen nahmen nun auf der Arbeitnehmerbank auch Vertreter der leitenden Angestellten Platz; zum anderen verfügt der von der Kapitalseite gestellte Aufsichtsratsvorsitzende bei Stimmengleichheit über ein Doppelstimmrecht. Trotz dieser aus Sicht der Gewerkschaften angesichts aufgrund des Doppelstimmrechts des Aufsichtsratsvorsitzenden fehlender tatsächlicher Parität immer noch unzureichenden Mitbestimmung gab das Mitbestimmungsgesetz von 1976 dem Mitbestimmungsgedanken erheblichen Auftrieb. Insbesondere zu Hochzeiten des Neoliberalismus während der 1990er-Jahre und Anfang dieses Jahrtausends wurde die Unternehmensmitbestimmung als veraltet kritisiert, mit dem Argument, sie sei den Anforderungen einer modernen Wirtschaft und der Globalisierung nicht gewachsen. Auch hier gibt es aber zumindest empirische Hinweise, dass Zufriedenheit und Motivation der Beschäftigten durch Mitbestimmung steigen. Die Praxis der Mitbestimmung Besser als quantitative Messungen kann oft praktische Anschauung bei der Beurteilung helfen.
This paper describes strategies toward model-based automation of intravenous anaesthesia employing advanced control techniques. In particular, based on a detailed compartmental mathematical model ...featuring pharmacokinetic and pharmacodynamics information, two alternative model predictive control strategies are presented: a model predictive control strategy, based on online optimization, the extended predictive self-adaptive control and a multiparametric control strategy based on offline optimization, the multiparametric model predictive control. The multiparametric features to account for the effect of nonlinearity and the impact of estimation are also described. The control strategies are tested on a set of 12 virtually generated patient models for the regulation of the depth of anaesthesia by means of the bispectral index (BIS) using Propofol as the administrated anaesthetic. The simulations show fast response, suitability of dose, and robustness to induce and maintain the desired BIS setpoint.
•Multi-parametric model predictive control (mp-MPC) for hypnosis during anesthesia.•Combined control design of mp-MPC and online parameter estimation.•Evaluation of control strategy for uncertainty ...originated by patient variability.•Controller's dynamics are adjusted to the individual patient's sensitivity.•Closed loop control validation for induction and disturbance rejection.
This paper addresses inter- and intra-patient variability in the context of automated drug delivery during anesthesia. A combined strategy of model predictive control (MPC) and least squares online parameter estimation for the control of the hypnotic depth, measured by the Bispectral Index (BIS), under uncertainty is presented, where the uncertainty originates from patient variability. The parameter with the highest sensitivity, C50 the effect site concentration at 50% drug effect, is estimated online. The performance of the closed loop control design is shown for induction and maintenance of volatile anesthesia. In the maintenance phase, the control strategy is evaluated for predefined disturbances that are commonly occurring during surgery. The presented approach shows an improved performance compared to the nominal MPC controller under uncertainty.
Continuous milli-scale reactors with internal mixing elements are increasingly used in the chemical industry and considered for polymerization processes. Their small scale makes them especially ...susceptible to fouling. Addressing this problem, this article presents a computational fluid dynamics (CFD) analysis of a Miprowa millireactor channel. The flow field is examined with the finite-element based software package COMSOL Multiphysics to identify areas of low velocity, generally prone to fouling during polymerization reactions. For simplicity, the flow is assumed incompressible and isothermal, using the material properties of water. Three geometry modifications to the mixing elements are proposed. Numerical simulations of the flow field around the proposed mixing elements show a reduction in areas with stagnating flow by 20%, reducing the fouling potential without substantially affecting other metrics such as the pressure loss.
Hollow fiber sorbents have overcome many limitations of packed-bed adsorbers. To fully exploit their potential, holistic design methods are crucial, but overall optimization strategies are lacking ...and are presented here for the first time. To showcase the methodology, we investigated the separation of H2 and CO2 using hollow fiber sorbents made of zeolites and cellulose acetate. The specific purification costs could be reduced by 13% using the optimization methodology. The purification costs rise from 0.65 €/kg to 0.85 €/kg with increasing product purity from 99% to 99.99%. An increase of the adsorption capacity by 50% only decreases the cost by 5%. Yet, the major conclusion relates to the hollow fiber dimensions, which only change slightly with product requirements and sorption capacities. The optimal inner and outer fiber diameter are in the range of 0.33–0.38 mm as well as 0.80–0.91 mm, respectively. The optimal fiber length varies between 98.7 and 103.1 cm. Thus, we conclude that the identified fiber design is close to a generic optimum.
The presented procedure aims to establish an in-depth understanding of a derived mathematical model for drug distribution, pharmacokinetics, and drug effect, pharmacodynamics, during volatile ...anesthesia. A physiologically based, patient-specific model is derived, where the pharmacokinetic (PK) part consists of multiple blood and tissue compartmental models, each adjusted to the weight, height, gender, and age of the patient. The pharmacodynamic (PD) part is described by an effect site compartment and the Hill equation both linking the hypnotic effect measured by the Bispectral Index (BIS) to the arterial anesthetic concentration. Via a global sensitivity analysis the patient-specific PK and PD variables and parameters are analyzed regarding their influence on the measurable outputs, which are the end-tidal concentration of the volatile anesthetic and the BIS. Via this analysis, the uncertainty introduced by PD variability is identified to be more significant than the uncertainty introduced by PK variability. A case study of isoflurane-based anesthesia shows that the simulation results of the individualized PK variables are in good accordance with the measured end-tidal concentration. However, the PD parameters need to be estimated online to predict the hypnotic depth, measured by the BIS, correctly. As a result of this study, the aim should be to focus on the individual identification of the PD parameters before and during anesthesia with future application in safe and robust model predictive control.
For years, TUI AG was pressured by active shareholders to concentrate on its core business - tourism - and break free from the shipping company Hapag-Lloyd AG. For five years, by constantly adopting ...new group restructuring measures, the Board managed to fend off the shareholders' demand. Then, in 2008, it finally opted to sell, triggering an unprecedented fight by the workforce to prevent the company from being sold to Asia. In the end, dogged persistence, strategic skill and sheer courage enabled the Board to pull off something that virtually everyone had written off as impossible: Hapag-Lloyd was sold to a Hamburg-based consortium and the associated jobs remained in Hamburg.
Pendant des années, la société TUI AG a subi la pression d'actionnaires actifs, qui exigeaient qu'elle se concentre sur son métier de base, le tourisme, et se sépare de sa filiale maritime, Hapag-Lloyd AG. Le directoire a réussi à résister pendant cinq ans grâce à d'incessantes mesures de restructuration du groupe. Mais en 2008, il s'est finalement décidé à vendre. Il s'en est suivi une lutte sans précédent du personnel, qui voulait empêcher la vente de l'entreprise en Asie. À force de ténacité, d'habileté stratégique et de courage, il a réussi ce que d'aucuns jugeaient impossible: Hapag-Lloyd a été vendue à un consortium de Hambourg. Les emplois ont été maintenus à Hambourg.
Jahrelang wurde die TUI AG von aktiven Aktionären unter Druck gesetzt. Sie forderten, TUI solle sich auf ihr Kerngeschäftsfeld Touristik konzentrieren und von der Schifffahrtstochter Hapag-Lloyd AG trennen. Mit immer neuen Konzernumbaumaßnahmen konnte sich der Vorstand fünf Jahre lang erfolgreich dagegen wehren. 2008 entschied er sich jedoch zum Verkauf. Es begann ein beispielloser Kampf der Belegschaft, die einen Verkauf des Unternehmens nach Asien verhindern wollte. Mit Hartnäckigkeit, strategischem Geschick und Mut gelang ihnen schließlich, was kaum jemand für möglich gehalten hatte: Hapag-Lloyd wurde an ein Hamburger Konsortium verkauft. Die Arbeitsplätze blieben in Hamburg.
The contributions of this thesis are organised in two parts. Part I presents a mathematical model for drug distribution and drug effect of volatile anaesthesia. Part II presents model predictive ...control strategies for depth of anaesthesia control based on the derived model. Closed-loop model predictive control strategies for anaesthesia are aiming to improve patient's safety and to fine-tune drug delivery, routinely performed by the anaesthetist. The framework presented in this thesis highlights the advantages of extensive modelling and model analysis, which are contributing to a detailed understanding of the system, when aiming for the optimal control of such system. As part of the presented framework, the model uncertainty originated from patient-variability is analysed and the designed control strategy is tested against the identified uncertainty. An individualised physiologically based model of drug distribution and uptake, pharmacokinetics, and drug effect, pharmacodynamics, of volatile anaesthesia is presented, where the pharmacokinetic model is adjusted to the weight, height, gender and age of the patient. The pharmacodynamic model links the hypnotic depth measured by the Bispectral index (BIS), to the arterial concentration by an artificial effect site compartment and the Hill equation. The individualised pharmacokinetic and pharmacodynamic variables and parameters are analysed with respect to their influence on the measurable outputs, the end-tidal concentration and the BIS. The validation of the model, performed with clinical data for isoflurane and desflurane based anaesthesia, shows a good prediction of the drug uptake, while the pharmacodynamic parameters are individually estimated for each patient. The derived control design consists of a linear multi-parametric model predictive controller and a state estimator. The non-measurable tissue and blood concentrations are estimated based on the end-tidal concentration of the volatile anaesthetic. The designed controller adapts to the individual patient's dynamics based on measured data. In an alternative approach, the individual patient's sensitivity is estimated on-line by solving a least squares parameter estimation problem.
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