A sequential semidefinite programming method and an application in passive reduced-order modeling

We consider the solution of nonlinear programs with nonlinear semidefiniteness constraints. The need for an efficient exploitation of the cone of positive semidefinite matrices makes the solution of such nonlinear semidefinite programs more complicated than the solution of standard nonlinear programs. In particular, a suitable symmetrization procedure needs to be chosen for the linearization of the complementarity condition. The choice of the symmetrization procedure can be shifted in a very natural way to certain linear semidefinite subproblems, and can thus be reduced to a well-studied problem. The resulting sequential semidefinite programming (SSP) method is a generalization of the well-known SQP method for standard nonlinear programs. We present a sensitivity result for nonlinear semidefinite programs, and then based on this result, we give a self-contained proof of local quadratic convergence of the SSP method. We also describe a class of nonlinear semidefinite programs that arise in passive reduced-order modeling, and we report results of some numerical experiments with the SSP method applied to problems in that class

Hilft die WTO Entwicklungsländern? Theoretische und empirische Aspekte

Der Autor untersucht, inwieweit sich die WTO-Eckpfeiler der Reziprozität und des Meistbegünstigungsprinzips sowie Koalitionen auf Entwicklungsländer auswirken. Es zeigt sich in theoretischen und empirischen Untersuchungen, dass die genannten Aspekte das Potenzial aufweisen, die Position von Entwicklungsländern bei den multilateralen Verhandlungen zu stärken. Eine fairere Verteilung der Außenhandelsgewinne geht jedoch stets mit einer verringerten Effizienz einher, sodass sich auch hier ein fundamentaler Zielkonflikt zwischen Gleichheit und Effizienz einstellt

Sustainable Business Model Design

This article introduces the “Sustainable Business Model Design” (SBMD) framework, an integrative methodology that synthesises sustainable business model theory with Alexandrian pattern theory. Emphasising a pragmatic interpretation of design as transformative action, the framework’s foundations are explored, seeking to consolidate the theoretical underpinnings guiding SBMD and elucidate its principal conceptual components. The article further delves into the practical application of the framework as a tool for problem-solving and idea generation. It concludes with a discussion of analogical reasoning and conceptual combination, shedding light on the creativity-enhancing efficacy of SBMD patterns. Additionally, the article is a succinct primer for business designers interested in the practical utilisation of SBMD, particularly within contexts such as sustainability innovation and ESG strategy workshops

Buergerversicherung vs. Gesundheitspraemie – Vergleich der Reformoptionen zur Finanzierung der Gesetzlichen Krankenversicherung

The wage-dependence of the Public Health Insurance (PHI) as well as the somewhat inconsistent parallel coverage via PHI and private health insurance constitute drawbacks of the present health care revenue system, leading to undesirable distributional and allocative patterns and disadvantages in the course of demographic and economic change. Two conflicting approaches, the “Buergerversicherung” (“Citizens’ Health Insurance”) and the “Gesundheitsprämie” (“Flat Rate Health Insurance”) try to remedy these by way of different methods – the former with a statutory health insurance for all and a comprehensive income basis for proportionate health insurance contributions, the latter with a flat rate contribution for the present PHI including a massive tax subsidy for the contributions for low-income groups and children. The paper presents simulations of the distributional effects. Differing effects become evident. Moreover these patterns also reflect different “philosophies” of social welfare and public revenue regimes. The “Bürgerversicherung” reduces payments by wage and wage-replacement earners and generally by low income groups, the “Gesundheitspraemie” favors higher-income individuals and particularly two-earner married couples.Social Health Insurance System, Public Finance

The Distributional Effect of Commuting Subsidies - Evidence from Geo-Referenced Data and Large-Scale Policy Reform

Tax legislation in virtually all OECD countries foresees tax breaks for commuters. Such commuting allowances are implemented with the aim to raise matching efficiency in the labor market and / or to promote an equalization of net wages for workers independent of the length of their commute. Despite the fiscal magnitude of these subsidies (e.g. in Germany the sum of foregone tax income from commuting tax breaks amounts to 6 billion Euros annually) little is known about their effects on worker and firm behavior. In this paper we use the unexpected repeal of commuting subsidies in Germany between 2007 and 2009, which has affected different groups of workers to a different extent, as a natural experiment. Drawing on a large data set of geo-referenced employer-employee data and applying a difference-in-difference approach, we estimate the effect of commuting subsidies on wages and employment. Beyond the direct effect of the commuting tax break our results allow to draw inference on three key variables in labor economics: wage elasticity of labor supply, bargaining power of workers, and the wage elasticity of locational choice. We find that workers who lose some of their net wage as a result of the reform experience increases in gross wages of .6 per cent. Adjustments in gross wages differ, however, substantially across industries and across educational status, which can be taken as evidence for differential bargaining power across worker groups

Zuzahlungen nach dem GKV-Modernisierungsgesetz (GMG) unter Beruecksichtigung von Haertefallregelungen

The law for the Modernisation of the Social Health Insurance System 2003 ("GKV-Modernisierungsgesetz – GMG" 2003) provides, among other measures, for a noticeable increase in co-payments and also for a reduction of possibilities for claiming exemptions from co-payments. Against this backdrop, the authors of the paper present, at the start, the varying news on co-insurance payments held by different political groups. Thereafter, the theoretical foundations of co-payments are described. Finally, on the basis of extensive empirically founded computations, the effects of the new co-payment rules (together with relevant new exemptions) are compared with the effects of the rules still in force.Social Health Insurance System, co-payment, public finance

Sustainable Value Creation Through Business Models: The What, the Who and the How

Purpose: We discuss traditional assumptions about value creation and confront these with current viewson sustainable value creation (SVC). Against this backdrop, the articles contained in the special issue‘Sustainable Value Creation Through Business Models’ are introduced, and their contributions to the explorationof SVC are highlighted.*Methodology: Assumptions about value creation are summarised and turned into an initial theoreticalframework concerning the what, who and how of value creation. This framework is used to structure anddiscuss current views on SVC that have been presented in the sustainable business model (SBM) litterature.Findings: The proposed framework identifies cornerstones for theorising about SVC in regard to thewhat, who and how of value creation. A main finding is that, although value creation and SVC are widelydiscussed in the literature, there are huge gaps in terms of the who, what and how of value creation, particularlyin the SBM field.Research implications and limitations: The major implication is that the SBM discourse still lacks clearSVC concepts, and closing this gap may enable the creation of a new multi- and interdisciplinary researchprogramme. A major limitation of this paper is the mainly theoretical and preliminary nature of the presenteddiscussion and framework.Originality and value: There is a surprising dearth of definitions and concepts of value creation in boththe traditional business model and SBM research. The originality and value of this paper lie in its potentialto stimulate further research on the theoretical foundations of SVC. Various theoretical propositionsare developed, including notions such as stakeholder-responsive and relational interpretations of valuecreation

Toward Collaborative Cross-Sector Business Models for Sustainability

Sustainability challenges typically occur across sectoral boundaries, calling the state, market, andcivil society to action. While consensus exists on the merits of cross-sector collaboration, ourunderstanding of whether and how it can create value for various, collaborating stakeholders is still limited. This Special Issue focuses on how new combined knowledge on cross-sector collaboration and business models for sustainability can inform the academic and practitioner debates about sustainability challenges and solutions. We discuss how cross-sector collaboration can play an important role for the transition to new and potentially sustainability-driving business models given that value creation, delivery and capture of organizations are intimately related to the collaborative ties with their stakeholders. Sustainable alternatives to conventional business models tend to adopt a more holistic perspective of business by broadening the spectrum of solutions and stakeholders and, when aligned with cross-sector collaboration, can contribute new ways of addressing the wicked sustainability problems humanity faces

Supporting Named Entity Recognition and Document Classification for Effective Text Retrieval

In this research paper, we present a system for named entity recognition and automatic document classification in an innovative knowledge management system for Applied Gaming. The objective of this project is to facilitate the management of machine learning-based named entity recognition models, that can be used for both: extracting different types of named entities and classifying text documents from different sources on the Web. We present real-world use case scenarios and derive features for training and managing NER models with the Stanford NLP machine learning API. Then, the integration of our developed NER system with an expert rule-based system is presented, which allows an automatic classification of text documents into different taxonomy categories available in the knowledge management system. Finally, we present the results of two evaluations. First, a functional evaluation that demonstrates the portability of our NER system using a standard text corpus in the medical area. Second, a qualitative evaluation that was conducted to optimize the overall user interface of our system and enable a suitable integration into the target environment