Migration ist in dieser Stadt eine Tatsache. Urban politics of citizenship in der neoliberalen Stadt

Der Beitrag rekonstruiert die politics of citizenship aktueller städtischer Integrationsprogrammatiken. Im Zuge der Anpassung des Integrationsparadigmas an die Logik der ‚unternehmerischen Stadt‘ werden nationale Traditionen von Stadtpolitik infrage gestellt. Entsprechende Konzepte problematisieren (Post-)Migrant_innen als zu aktivierende Stadtbürger_innen. Anstatt diese Beobachtung zu einer negativen Kritik an Neoliberalisierungsprozessen kurzzuschließen, schlägt der Beitrag vor, die neuen staatlichen Problematisierungen als (möglicherweise nützliche) Bedingungen für Kämpfe um eine gleichberechtigte Teilhabe in der Stadt zu verstehen. Anhand der Genese des Frankfurter Konzepts wird gezeigt, dass unter neoliberalen Umständen postnationale wissenschaftliche Konzepte für die Regierung der Stadt mobilisiert werden. Damit repräsentiert das Konzept (Post-)Migration als Bestandteil einer ‚vielfältigen‘ Normalität – an der sich Stadtpolitik in Zukunft auch politisch messen lassen müsste

Composing Conversational Negation

Negation in natural language does not follow Boolean logic and is therefore inherently difficult to model. In particular, it takes into account the broader understanding of what is being negated. In previous work, we proposed a framework for the negation of words that accounts for 'worldly context'. This paper extends that proposal now accounting for the compositional structure inherent in language within the DisCoCirc framework. We compose the negations of single words to capture the negation of sentences. We also describe how to model the negation of words whose meanings evolve in the text.Comment: In Proceedings ACT 2021, arXiv:2211.0110

A Pipeline For Discourse Circuits From CCG

There is a significant disconnect between linguistic theory and modern NLP practice, which relies heavily on inscrutable black-box architectures. DisCoCirc is a newly proposed model for meaning that aims to bridge this divide, by providing neuro-symbolic models that incorporate linguistic structure. DisCoCirc represents natural language text as a `circuit' that captures the core semantic information of the text. These circuits can then be interpreted as modular machine learning models. Additionally, DisCoCirc fulfils another major aim of providing an NLP model that can be implemented on near-term quantum computers. In this paper we describe a software pipeline that converts English text to its DisCoCirc representation. The pipeline achieves coverage over a large fragment of the English language. It relies on Combinatory Categorial Grammar (CCG) parses of the input text as well as coreference resolution information. This semantic and syntactic information is used in several steps to convert the text into a simply-typed $\lambda$-calculus term, and then into a circuit diagram. This pipeline will enable the application of the DisCoCirc framework to NLP tasks, using both classical and quantum approaches.Comment: 39 pages, many figure

Simplified mathematical model of proton exchange membrane fuel cell based on horizon fuel cell stack

This paper presents a simplified zero-dimensional mathematical model for a self-humidifying proton exchange membrane (PEM) fuel cell stack of 1 kW. The model incorporates major electric and thermodynamic variables and parameters involved in the operation of the PEM fuel cell under different operational conditions. Influence of each of these parameters and variables upon the operation and the performance of the PEM fuel cell are investigated. The mathematical equations are modeled by using Matlab–Simulink tools in order to simulate the operation of the developed model with a commercial available 1 kW horizon PEM fuel cell stack (H-1000), which is used for the purposes of model validation and tuning of the developed model. The model can be extrapolated to higher wattage fuel cells of similar arrangements. New equation is presented to determine the impact of using air to supply the PEM fuel cell instead of pure oxygen upon the concentration losses and the output voltage when useful current is drawn from it

Experimental real-time optimization of a solid oxide fuel cell stack via constraint adaptation

The experimental validation of a real-time optimization (RTO) strategy for the optimal operation of a solid oxide fuel cell (SOFC) stack is reported in this paper. Unlike many existing studies, the RTO approach presented here utilizes the constraint-adaptation methodology, which assumes that the optimal operating point lies on a set of active constraints and then seeks to satisfy those constraints in practice via the addition of a correction term to each constraint function. These correction terms, also referred to as “modifiers”, correspond to the difference between predicted and measured constraint values and are updated at each steady-state iteration, thereby allowing the RTO to iteratively meet the optimal operating conditions of an SOFC stack despite significant plant-model mismatch. The effects of the filter parameters used in the modifier update and of the RTO frequency on the general performance of the algorithm are also investigated

Coordination of converter and fuel cell controllers

Load following fuel cell systems depend on control of reactant flow and regulation of DC bus voltage during load (current) drawn from them. To this end, we model and analyse the dynamics of a fuel cell system equipped with a compressor and a DC–DC converter. We then employ model-based control techniques to tune two separate controllers for the compressor and the converter. We demonstrate that the lack of communication and co-ordination between the two controllers entails a severe tradeoff in achieving the stack and power output objectives. A co-ordinated controller is finally designed that manages the air and the electron flow control in an optimal way. We demonstrate our results during specific and critical load changes around a nominal operating point. Although our analysis does not cover wide operating region, it provides insight on the level of controller co-ordination necessary in non-hybridized fuel cell power supply. The shut-down and start-up procedures will be investigated in future work. Copyright © 2005 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48762/1/1146_ftp.pd