Controlling sliding droplets with optimal contact angle distributions and a phase field model

We consider the optimal control of a droplet on a solid by means of the static contact angle between the contact line and the solid. The droplet is described by a thermodynamically consistent phase field model from [Abels et al., Math. Mod. Meth. Appl. Sc., 22(3), 2012] together with boundary data for the moving contact line from [Qian et al., J. Fluid Mech., 564, 2006]. We state an energy stable time discrete scheme for the forward problem based on known results, and pose an optimal control problem with tracking type objective.TU Berlin, Open-Access-Mittel - 201

Labor Market Policies and Women’s Labor Market Activity in the United States and Germany

In terms of per capita Gross Domestic Product (GDP) and many other measures, the United States and Germany are both economic leaders in the global world. However, gender gaps persist in the labor markets of both countries. This paper examines these gender gaps and various labor market policies that are intended to reduce them. The policies examined include gender equality policies and family-oriented policies in the two countries. Over the last few decades, most of the OECD (Organisation for Economic Co-operation and Development) countries have experienced low and decreasing birth rates. In response, several countries have introduced parental leave regulations to make the combination of parenthood and a working career more appealing, especially to women. Germany implemented a new family leave policy called “Elterngeld” in 2007 and also passed a gender quota law for the private sector in 2014. In contrast, the United States has no national statutory maternity leave policy and relatively few policies. This paper elaborates on these labor and family policies and interprets the nations’ labor market data in their light. The paper analyzes a variety of data for women in the United States and Germany, including: unemployment rates, relative wage rates, labor force participation rates, occupational distribution, birth rates, and available childcare. Data from various sources, including the OECD, are also presented to give general background on both countries’ economic status, histories, and policies. This paper reviews the economics literature on the effects of family-oriented policies. This paper then concludes with a discussion of how if these countries choose to improve their policies to assist both women and families, it would aid the country and not significantly hinder it. Leave policies have not been shown to have a significant effect on firms and if less than one year, can improve job continuity for women

Decidability Results on the Existence of Lookahead Delegators for NFA

In this paper, we study lookahead delegators for nondeterministic finite automata (NFA), which are functions that deterministically choose transitions by additionally using a bounded lookahead on the input word. Of course, the delegator has to lead to an accepting state for each word that is accepted by the NFA. In the special case where no lookahead is allowed, a delegator coincides with a deterministic transition function that preserves the language. Typical decision problems are to decide whether a delegator with a given fixed lookahead exists, or whether a delegator with some bounded lookahead exists for a given NFA. In a paper of Ravikumar and Santean from 2007, the complexity and decidability of these questions have been tackled, mainly for the case of unambiguous NFA. In this paper, we revisit the subject and provide results for the case of general NFA. First, we correct a complexity result from the above paper by showing that the existence of delegators with fixed lookahead can be decided in time polynomial in the number of states. We use two player games on graphs as a tool to obtain the result. As second contribution, we show that the problem becomes PSPACE-complete if the bound on the lookahead is a part of the input. The third result provides a bound on the maximal required amount of lookahead. We use this to show that the (previously open) problem of deciding the existence of a bounded lookahead delegator is also PSPACE-complete

Uncertainty Analysis for Data-Driven Chance-Constrained Optimization

In this contribution our developed framework for data-driven chance-constrained optimization is extended with an uncertainty analysis module. The module quantifies uncertainty in output variables of rigorous simulations. It chooses the most accurate parametric continuous probability distribution model, minimizing deviation between model and data. A constraint is added to favour less complex models with a minimal required quality regarding the fit. The bases of the module are over 100 probability distribution models provided in the Scipy package in Python, a rigorous case-study is conducted selecting the four most relevant models for the application at hand. The applicability and precision of the uncertainty analyser module is investigated for an impact factor calculation in life cycle impact assessment to quantify the uncertainty in the results. Furthermore, the extended framework is verified with data from a first principle process model of a chloralkali plant, demonstrating the increased precision of the uncertainty description of the output variables, resulting in 25% increase in accuracy in the chance-constraint calculation.BMWi, 0350013A, ChemEFlex - Umsetzbarkeitsanalyse zur Lastflexibilisierung elektrochemischer Verfahren in der Industrie; Teilvorhaben: Modellierung der Chlor-Alkali-Elektrolyse sowie anderer Prozesse und deren Bewertung hinsichtlich Wirtschaftlichkeit und möglicher HemmnisseDFG, 414044773, Open Access Publizieren 2019 - 2020 / Technische Universität Berli

Annual Survey of Virginia Law: Business and Corporate Law

This article reviews recent developments in the law affecting Virginia businesses and corporations. Part II discusses several acts of the 1994 session of the Virginia General Assembly that amend Virginia\u27s corporate, partnership, and limited liability company statutes. Part III discusses recent judicial decisions in Virginia courts that address business and corporate law issues

Politicized climate change communication: An integrative complexity analysis

The vast majority of scientists agree that anthropogenic activities have caused the level of CO2 in the atmosphere to rise at an unprecedented rate, and that the consequences of such a rise may very well be extreme. Despite these warnings, the American people do not possess, on average, the same level of concern towards climate change as scientists. The polarization of media in recent decades, the prevalence of selective exposure, and the general position on climate change of the two major political parties have led to liberals and conservatives consuming different information relevant to climate science. While evidence exists that there are accuracy differences in the information consumed by these two groups, there is also reason to suspect that linguistic differences are also present. This investigation sought to understand whether the dissemination of climate science information contained different types of complexity across conservative and liberal media. Because complexity has important attitudinal consequences, scientifically investigating whether the climate science information being dispersed by the leading conservative (FOX) and liberal (MSNBC) media outlets differs in its integrative complexity is a critical step in understanding the current attitudinal divide. Trained complexity coders scored 30 articles published on the websites of FOX and MSNBC for the two levels of Integrative Complexity: dialectical and elaborative. It was expected that FOX articles would contain higher levels of dialectical complexity than MSNBC, and that MSNBC articles would contain higher levels of elaborative complexity than FOX. Results revealed evidence consistent with the hypothesized pattern of complexity use; however, these differences between media outlets’ use of integrative complexity did not attain conventional levels of statistical significance. I discuss possible reasons for this failure to find statistical significance and future directions

Startup of a reactive distillation process with a decanter

The startup of a reactive distillation process for the production of propyl acetate including a decanter is studied. A simulation model is presented which describes the whole startup from a cold and empty state and takes into account the liquid phase split in the decanter. The simulation model is successfully validated with own dynamic experimental data. Different startup strategies are developed and analysed in simulation studies showing the high influence of the initial charging of decanter and reboiler on the startup time

Investigation of the Degradation of Chelate Complexes in Liquid Redox Desulfurization Processes

Metal complexes such as Fe‐EDTA, which are used as pseudo‐catalysts or oxygen carriers in wet oxidative desulfurization processes, are subject to a degradation mechanism that significantly influences the economics of such processes. Therefore, this study presents a methodology for determining the degree of degradation during the reactive hydrogen sulfide absorption in a Fe‐EDTA solution within a continuously operating semi‐batch reactor system. For this purpose, the reactive conversion of H2S in the liquid phase was used as a reference, and a clear dependence of the degradation on the pH could be shown. In addition, indicators are introduced that evaluate the observed pH dependency of the degradation and distinguish pH‐induced effects such as the pH‐dependent absorption performance of H2S.TU Berlin, Open-Access-Mittel - 202

Direct Numerical Simulations of Liquids on Microstructured Surfaces: Analysing the Fluid Dynamics on Packing

Structured high performance packing for packing columns have macrostructures, e.g., corrugated or folded sheets, and in many cases microstructures or surface topographies with geometrical dimensions in the same order of magnitude as the film thicknesses. For an optimal design of microstructured surfaces and for the development of novel methodologies to predict the mass transfer, a reliable description of the influence of these microstructures is crucial. To research the influence of these microstructures on the liquid film in detail, and later on optimize the geometry, Direct Numerical Simulations applying the Cahn-Hilliard-Navier-Stokes (CHNS) equations were performed for this study. The model and the implementation were validated against analytical solutions for undisturbed laminar film flows. The influence of two single microstructures (triangle and rectangle) on the gas-liquid interface and the velocity in the liquid were systematically investigated. Thereby, it was observed, that small microstructures in comparison to the film thickness have no influence on the gasliquid interface. In contrast, higher structures could increase the interfacial area. The results indicate, that systematic studies on a wide range of geometries, phase properties and gas velocities can give valuable information on the path to optimal microstructures