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IT-Governance, Prüfung & Revision mal agil gedacht! Herausforderungen und Notwendigkeit eines Perspektivwechsels für IT-Governance, Prüfung & Revision viele Fallbeispiele zeigen die praktische Umsetzbarkeit auf Agilität und der Einsatz agiler Methoden sind heute nicht mehr nur auf IT-Projekte begrenzt, sondern prägen zunehmend ganze Organisationen. Dieses Buch zeigt auf, wie sich IT-Governance, Prüfung & Revision erfolgreich dem durch Agilität ausgelösten Wandel stellen können und wie sich der Umgang mit den Kernthemen Risiko & Unsicherheit verändert. Zum einen werden Ansätze für eine agile IT-Governance und eine agile Prüfung & Revision beschrieben, indem sie sich agile Werte und Vorgehensweisen zu eigen machen. Zum anderen werden IT-Governance, Prüfung & Revision befähigt, agile Projekte angemessen steuern und wirksam prüfen zu können.
This article provides insights into the modalities of business-model change and innovation. On the basis of an analysis of empirical data of small and medium enterprises, a transition from wine production centrism to its expanded use in hospitality and tourism is explored. Previous research on wine tourism and hospitality predominantly focuses on a destination perspective, neglecting the organizational winery perspective. The article deploys a mixed methods approach, combining netnography and a content analysis for data collection with grounded research and clustering for theory building. The sample size included 885 German wineries. Data stemmed from two distinct sources (websites and a secondary publication in form of a wine guide) and has been analyzed through a two-step clustering algorithm as well as a Principal Component Analysis (PCA). The two-step clustering algorithm resulted in nine different business models while the PCA analysis grouped the variables into the following two categories: basic winery business model (BM) and BM extension into hospitality and tourism, thereby validating the difference between the two constructs. The results point to the diverse nature of business model extensions of wineries in tourism and hospitality, depending on their organizational type and size. This study offers a classification of small and medium sized enterprise’s strategic business model expansion, and explores the expansion of the wine industry through wine hospitality and tourism services, starting with the winery organizational perspective, which has not been done before.
The purpose of this paper is to examine the impact that various types of business model extensions (hospitality and tourism, online sales platforms, and sustainability) have on the winery business. The research is based on company data and online observations of N = 886 German wineries and deploys a content analysis, netnography, and structural equation modeling (SEM) in order to test the hypothesis on business model extensions of wineries, which have been set forth in the previous literature. The findings indicate that business model extensions related to online sales platforms have a positive impact on winery business size. These results mean that developing online sales platforms enlarges the winery BM (business model) size and type (manager-run, state-owned, or cooperatives). The paper presents in detail the impact of winery BM extensions on winery BM model type and size, thereby contributing to the literature on business model innovation.
This study set out to uncover brand positioning configurations by presenting state-of-the-art brand management literature and applying a novel, mixed-methods approach to examine the under-researched wine industry transformation towards open innovation in branding. German winery brands were analyzed using a multimethod approach leaning on a novel netnographic methodology and multiple sources. The sample included 572 wineries from all 13 German wine regions with website text data and online review text data from each winery. The study identified nine prime words used to describe both brand identity as well as wine brand image. It revealed word–price clusters of brand identity and image. The results offer insights into communication and pricing opportunities for wine brand identity as well as image, thereby contributing to open brand innovation.
The article improves understanding on leveraging new technology for DT (digital transformation) of grape harvest in SME wineries. It provides evidence on technologies used and workplace types deployed in grape harvesting, as well as strategic paths in deploying new technology, thereby contributing to the literature on networked sensing and seizing capabilities in the wine industry 4.0. The research approach is explorative and qualitative drawing on 31 interviews with wine industry 4.0 experts and managers, mostly owners of SMEs: wineries, wine software and wine machinery enterprises. Resulting findings serve as a roadmap for digital transformation of grape harvest process in SME wineries explaining technologies and work roles necessary for DWT (digital workplace transformation), as well as strategic paths of deployment of novel grape harvest technology. Previous research on the wine industry 4.0 has focused on BMI, while this research expands the focus to include a wider concept of technology adoption strategy as well as DWT. The research identifies two types of factors impacting the strategic deployment of grape harvest technology: pull factors, also termed servitization factors, as well as push factors, termed also digital transformation factors.
The purpose of this study is to research the antecedents of the sustainable travel decision-making of European travelers and thereby identify important lessons for the transition towards sustainable travel and tourism. The study is based on data collected through a representative survey, conducted in five European countries, with a sample of n = 5024 respondents. The results of descriptive statistics, EFA (Exploratory Factor Analysis) and FA (Factor Analysis) are presented in order to explore sustainable travel decision-making through environmental (policy-related and personal) attitudes and travel mode decision priorities in the European context. Furthermore, the study provides new evidence regarding the under-researched phenomenon of the attitude–behavior gap by presenting a model for the sustainability-oriented decision-making of travelers, including attitudes and travel mode priorities as antecedents. The results confirm the existence of moral licensing in travel decision-making, thereby extending the relevance of this theory into travel and tourism, which has not been done before. The denial of environmental issues is also being researched as regards its interaction with positive environmental attitudes, environmental travel mode priorities and non-environmental travel priorities, thereby advancing our understanding of the interplay between these categories. The interplay between the four categories furthers our understanding of the perplexity of travelers in terms of sustainable travel decision-making.
The reported research examines the impact of product portfolio labeling strategies on brand reputation and equity. A netnographic approach allowed to observe winery portfolio labeling approaches and create a typology of winery labeling strategies. Expert evaluation served to assess the dependent variable brand equity by deploying a regression analysis. For the observed wine industry, being part of the food industry, creating consistent and recognizable brands has a direct relevance for reducing (sustainability-related) food information overload and thereby building sustainable brand equity. The results uncover the relative importance of each of the six identified labeling strategies as well as their impact on reputation and brand equity creation. The results point to the need to establish a consistent, strategically founded product communication. Such an approach, with a positive effect on reputation building can serve to build sustainable brand equity. “Stuck in the middle”-type strategies apparently diminish winery brand equity exploitation. The findings contribute to the knowledge on food labels in product communication strategies and their impact on organizational brand equity, thereby having high relevance for the implementation of environmental certification initiatives in an organizational context. The article deploys a novel research approach in an under-researched area to provide new insights for further research as well as implications for practice.
The article explores SME (Small and Medium Sized Enterprises) brand strategies as a means to position and successfully engage in competitive markets. A derived typology of brand strategy types deals with social profiling and sheds light on brand strategy internalization of two current managerial paradigms—sustainability and co-creation. N = 895 German SME wineries were examined, leaning on a netnographic analysis of predominantly websites and social media interactions. A two-step clustering method thereby identified eight winery SME brand strategy types. The importance of sustainability across the identified eight brand strategy types is significant. Co-creation turned out to be a key profiling trait characterizing one brand strategy type. The typology illustrates strategic richness, with brand strategies leaning predominantly on traditional values, on sustainability, on external reputation, or on more innovative customer centric concepts such as co-creation. Hereby, the typology and the identified brand levers invite to strategically design brand management, governance, and sustainability. Wineries which focus on traditional positioning and legitimacy were found to be cautious in deploying co-creation through social media. Winery brands that are characterized by engagement in digital co-creation apparently either tend to expand their scope or partially combine it with traditional values, making them the most diverse type identified. Sustainability obviously needs to be addressed by all brand strategies. Despite industry and country focus, the analyses illustrate the relevance of socially-oriented profiling and highlights that sustainability has reached a status of a fundamental business approach still allowing to differentiate thereon. Furthermore, the business models of the SMEs need to deliver communicated values.
This study advances the research and methodological approach to measuring and understanding national-level destination competitiveness, sustainability and governance, by creating a model that could be of use for both developing and developed destinations. The study gives a detailed overview of the research field of measuring destination competitiveness and sustainability. It also identifies major predictors of destination competitiveness and sustainability and thereby presents destination researchers and practitioners with a useful list of priority areas, both from a global perspective and from the perspective of other similar destinations. Finally, the study identifies two major types of destination governance with implications for research, policy and practice across the destination life-cycle. The research deals with the analysis of the secondary data from the World Economic Forum Travel and Tourism Index (WEF T&T). Major types of destination governance and predictors of belonging to either one of the types, as well as inside cluster predictors have been extracted through a two-step cluster analysis. The results support the notion that a meaningful model of national-level destination governance needs to take into account different development levels of different destinations. The main limitation of the study is its typology creation approach, as it inevitably leads to simplifications.
Towards a conceptual framework for sustainable business models in the food and beverage industry
(2020)
Based on the WEF Travel & Tourism Report data, this study deploys k-means cluster analysis to build a global typology of national destination governance. Previous studies have focused on case studies, while this chapter focuses on classification of different destination types, by deploying indicators a set of following relevant indicators: wastewater treatment, fixed broadband internet subscriptions, ground transport efficiency, quality of roads, quality of railroad infrastructure, reliability of police services, ease of finding skilled employees. The results present a four-cluster solution of national destination governance types, as well as their major characteristics. The chapter than provides and discusses important implication for theory and practice of destination governance.
This article examines similarities and differences in the attitudes and social representations of destination managers towards implementing sustainable tourism between the mountain regions of the Alps and the Dinarides. Bearing in mind the transnational impacts (i.e., environmental, economic and social) of the tourism industry the research methodology adopted an international perspective by sending a questionnaire to tourism organizations in fourteen different countries in the Alps and the Dinarides. The research is interdisciplinary in nature, because it integrates knowledge from sustainability and management science with tourism geography and social psychology. The findings confirm that social representations of sustainable tourism differ significantly in the two mountain regions.
What are the processes behind efforts for more sustainable mountain destinations in the German Alps and what are the views of different tourism stakeholders on these processes? The research deals both with threats pushing the agenda of sustainable development (such as climate change and depletion of resources), indicators of sustainable tourism (to measure the scope of change), as well as cross-border cooperation and stakeholder engagement in the German Alps. The data was collected through 30 interviews with individuals dealing with tourism development and sustainable tourism development in the German Alps. The findings suggest that a holistic approach and collection and dissemination of data and knowledge on sustainability are the basis for developing sustainable mountain tourism. Implementation and monitoring should focus on specific flagship sustainable tourism products, as well as on a destination in a broader sense and the sustainable tourism market. Three themes emerged as important for implementation of sustainable tourism in the German Alps: indicators of sustainable tourism, cross-border cooperation and stakeholder engagement.
An exploratory study: Analysis of Serbian tourism market and identification of major market segments
(2016)
Selbstfahrende Arbeitsmaschinen für den Einsatz auf dem Boden der Tiefsee von beispielsweise 6000 m Tiefe existieren derzeit noch nicht. Im Rahmen der vorliegenden Untersuchungen wird das Problem des Antreibens und Steuerns schwerpunktmäßig mit dem Ziel behandelt, die Grundlagen für weiterführende Entwicklungen eines elektrohydraulischen Fahr- und Lenkantriebes zu schaffen. Hierzu wird ein Versuchsaggregat unter einem Umgebungsdruck von 60 MPa (600 bar) im Tiefsee-Simulator getestet. Die dabei gewonnenen Erkenntnisse sind bei der konstruktiven Weiterentwicklung solcher Antriebe übertragbar.
Entwicklung eines elektrohydraulischen Antriebsaggregats für den Einsatz in 6000 m Meerestiefe
(1986)
Selbstfahrende Arbeitsmaschinen für den Einsatz auf dem Boden der Tiefsee von beispielsweise 6000 Meter Tiefe existieren derzeit noch nicht. Im Rahmen der vorliegenden Untersuchung (BMFT-Förderkennzeichen MTK 0328) wurden die Grundlagen elektrohydraulischer Antriebe für Umgebungsdrücke von 60 MPa geschaffen und in einer Druckkammer erfolgreich getestet. Die dabei erhaltenen Erkenntnisse sind bei der konstruktiven Weiterentwicklung solcher Antriebe übertragbar.
Die Untersuchungen zum vorliegenden Beitrag wurden im Rahmen des deutsch-französischen Gemeinschaftsprojektes "Entwicklung von Manganknollenabbau- und Gewinnungsverfahren" durchgeführt. Auf deutscher Seite waren die Unternehmen PREUSSAG AG, Abteilung Meerestechnik in Hannover, die Versuchsanstalt für Wasser- und Schiffbau in Berlin, das Institut für Förderwesen der TH Karlsruhe, das Institut für Strömungsmechanik der Universität GH Paderborn und das Institut für Konstruktion der Universität GH Siegen beteiligt. Im zuletzt genannten Institut wurden elektrohydraulische Antriebe für Versuchsprototypen von geschleppten Manganknollenkollektoren und deren Steuerungen ausgelegt und auf ihre Einsatzfähigkeit im Tiefsee-Simulator getestet.
Bei den bisher üblichen Kannenwagen werden beim Wechseln von Spinnkannen an Spinnmaschinen meistens rotatorisch, z. B. mittels Drehkreuz bewegt. Die neue Lösung soll ohne Rotation eine exakte Positionierung der Spinnkannen beim Wechseln ermöglichen.$A Die Erfindung besteht darin, daß ein Kannenwechselwagen als schmales, raumsparendes modular aufgebautes Fahrzeug gestaltet ist, welches einen definierten translatorischen Wechsel der Spinnkannen in einem Kannenkreislauf ermöglicht. Das Fahrzeug kann ein- und/oder zweireihige Kannenreihen wechseln.$A Die Anwendung des erfindungsgemäßen Kannenwechselwagens kann an allen faserbandspeisenden und faserbandgespeisten Spinnereimaschinen, wie z. B. Karden, Strecken, Ring- und Rotorautomaten, erfolgen.
Der vorliegende Beitrag befaßt sich mit Automatisierungsmöglichkeiten in Textilbetrieben für konventionelle als auch für nichtkonventionelle Spinnverfahren. Aus der Vielzahl derzeit existenter Produktionsschritte werden die standardisierbaren Automatisierungskombinationen zwischen den eingesetzten Textilmaschinen von Karden bis zu Spinnautomaten herausgearbeitet. Hierfür werden die heute in der Praxis befindlichen Transportmittel aufgezeigt und, vom Materialfluß ausgehend, die Zuordnungsmöglichkeiten der Maschinen in den Produktionsschritten und deren Automatisierungsbausteine definiert. Durch eine ganzheitliche Betrachtungsweise werden je nach Automatisierungsziel die verschiedenen Lösungsansätze diskutiert und als Bausteine gegenübergestellt. Hierdurch werden neue mechatronische Automatisierungslösungen vorgestellt, die eine Integration von Produktionsschritten oder die Automatisierung zwischen den einzelnen Produktionsschritten ermöglicht.
Die Erfindung betrifft eine Spritzeinheit (1) für eine durch eine elektronische Steuerung gesteuerte Spritzgießmaschine, bestehend aus einer eine Schnecke (2) aufweisende Plastifiziereinheit (3), einem Antriebsmotor (4) und einem Getriebe (5) für den rotatorischen Antrieb der Schnecke (2). Das Getriebe (5) besteht aus einem Gehäuse, in dem eine mit dem Antriebsmotor (4) verbundene hydraulische Pumpe (7) angeordnet ist, die mit einem hydraulischen Motor (8) gekoppelt ist, der hydraulische Motor (8) treibt vorzugsweise über ein mechanisches Getriebe (9) die Schnecke (2) der Plastifiziereinheit (3) an. Erfindungsgemäß wird es damit möglich, mit geringem Aufwand die Rotationsdrehzahl der Schnecke (2) stufenlos zu regeln und so die gesamte Drehmomentenkennlinie des Antriebsmotors (4) zu nutzen. Das Getriebe wird vorzugsweise in kompakter Form ausgeführt, wobei die hydraulische Pumpe (7), der hydraulische Motor (8) und das mechanische Getriebe (9), das vorzugsweise als Planetengetriebe ausgeführt ist, koaxial angeordnet sind.
Yams of the most widely differing nature are produced in textile mills. The production stages necessary for this are carried out with the aid of textile machines. Between these individual textile machines - from cards to spinning machines - sliver cans serve as a rule as transport containers, in which the sensitive sliver material is temporarily stored, and presented to the next production stage.
Bei einem Streckwerk für eine Spinnereimaschine, insbesondere eine Regulierstrecke für Baumwolle, mit wenigstens zwei aufeinanderfolgenden Walzenpaaren, die jeweils eine mittels eines eigenen Elektromotors angetriebene Walze besitzen, ist eine elektronische Regeleinrichtung, die die Drehzahl wenigstens eines der Elektromotoren zum Ausgleichen von Ungleichmäßigkeiten eines zu verarbeitenden Faserbandes regelt, vorhanden.$A Um ein Streckwerk mit möglichst einfachen Mitteln so auszubilden, daß ein Zurückdrehen der Walzen bei Stillstand ausgeschlossen wird, ist den durch den einen Elektromotor angetriebenen Walzen mindestens ein Freilauf und der oder den durch den weiteren Elektromotor angetriebenen Walze oder Walzen mindestens ein weiterer Freilauf zugeordnet.
Mathematische Modellbildung zur Befahrbarkeitssimulation einer mobilen Tiefsee-Arbeitsmaschine
(1988)
Die Forderung nach dem systematischen Gewinnen von Tiefsee-Erzen, wie beispielsweise Manganknollen, mit selbstfahrenden Arbeitsmaschinen führt auf das schwierige Problem der Befahrbarkeit (Traffikabilität) des Tiefseebodens. Im vorliegenden Beitrag wird ein mathematisches Modell zur Befahrbarkeitssimulation einer ferngesteuerten Sammelmaschine vorgestellt. Am Beispiel eines, als Konstruktionsentwurf spezifizierten, aktiven Manganknollenkollektors im großtechnischen Maßstab werden die Modellannahmen und Voraussetzungen für den zugrundeliegenden Tiefseeboden, das Fahrwerk und die betrachteten Betriebszustände und Lastsituationen beschrieben. Mit Hilfe eines koordinatentransformierten Kräftesystems werden die Wechselbeziehungen zwischen Tiefseeboden und einem Vierraupen-Fahrwerk in einem Algorithmus zusammengefaßt. Als Anwendungsbeispiele werden mittels EDV-Programmierung interessierende Betriebszustände und Lastsituationen simuliert. Abschließend werden weitere Modellvarianten aufgezeigt.
Teilzeitarbeit, Mini-Jobs
(2004)
1. Aufl. 2001:Wissenswertes zu den Themen: Modelle der Teilzeitarbeit, arbeits- und sozialversicherungsrechtliche Fragen, Altersteilzeit. Flexibilität am Arbeitsplatz ist gefragt, Teilzeitarbeit gilt als Alternative zum Abbau von Vollzeitarbeitsplätzen, der Gesetzgeber fördert mit weit reichenden Verbesserungen (z.B. Bundeserziehungsgesetz zum 1.1.2001). Die Ratgeber-Literatur stellt sich auf die Zielgruppe und deren Interessen mit unterschiedlichen Schwerpunkten ein: arbeitsrechtlich (Uta Hoffmann: BA 12/00; Judith Kerschbaumer: Ba 11/00; Anke Wolf: BA 4/01), soziologisch (Martin Massow: BA 11/99), steuerlich (Max Becker: BA 7/00), Altersteilzeit (Stephan Rittweger: BA 7/01), für Lohnbüros (Wolfgang Schönfeld. zuletzt BA 7/01). Auch P. Hanau und S. Peters-Lange, Experten im Arbeits- und Sozialrecht, beraten gut verständlich über Vertragsfragen, soziale Sicherung und - knapp - Altersteilzeit. Mit Vertragsmustern, Checklisten, Beispielen, Randtiteln und verschiedenen Icons zur schnellen Orientierung. Beim Bestandsausbau Aktualität beachten. (1
Teilzeitarbeit
(1996)
Zumutbarkeit von Arbeit
(1994)
Zumutbarkeit von Arbeit
(1992)
An aircraft plume model has been developed on the basis of two coupled trajectory box models. Two boxes, one for plume and one for background conditions, are coupled by means of a mixing parameterization based on turbulence theory. The model considers comprehensive gas phase chemistry for the tropopause region including acetone, ethane and their oxidation products. Heterogeneous halogen, N2O5 and HOx chemistry on various types of background and aircraft-induced aerosols (liquid and ice) is considered, using state-of-the-art solubility dependent uptake coefficients for liquid phase reactions. The microphysical scheme allows for coagulation, gas-diffusive particle growth and evaporation, so that the particle development from 1s after emission to several days can be simulated. Model results are shown, studying emissions into the upper troposphere as well as into the lowermost stratosphere for contrail and non-contrail conditions. We show the microphysical and chemical evolution of spreading plumes and use the concept of mean plume encounter time, tl, to define effective emission and perturbation indices (EEIs and EPIs) for the North Atlantic Flight Corridor (NAFC) showing EEI(NOy) and EPI(O3) for various background conditions, such as relative humidity, local time of emission, and seasonal variations. Our results show a high sensitivity of EEI and EPIs on the exact conditions under which emissions take place. The difference of EEIs with and without considering plume processes indicates that these processes cannot be neglected.
For the winter 1999/2000 transport of air masses out of the vortex to mid-latitudes and ozone destruction inside and outside the northern polar vortex is studied to quantify the impact of earlier winter (before March) polar ozone destruction on mid-latitude ozone.
Nearly 112 000 trajectories are started on 1 December 1999 on 6 different potential temperature levels between 500–600 K and for a subset of these trajectories photo-chemical box-model calculations are performed. We linked a decline of −0.9% of mid-latitude ozone in this layer occurring in January and February 2000 to ozone destruction inside the vortex and successive transport of these air masses to mid-latitudes.
Further, the impact of denitrification, PSC-occurrence and anthropogenic chlorine loading on future stratospheric ozone is determined by applying various scenarios. Lower stratospheric temperatures and denitrification were found to play the most important role in the future evolution of polar ozone depletion.
Nitric acid partitioning in cirrus clouds: a synopsis based on field, laboratory and model studies
(2003)
From a synopsis of field, laboratory and model studies at T>205 K as well as from the field experiments POLSTAR at T<205 K we derive a general picture of the partitioning of nitric acid (HNO3) in cirrus clouds and a new hypothesis on the uptake of HNO3 on ice particles:
A substantial part of nitric acid remains in the gas phase under cirrus cloud conditions. The HNO3 removed from the gas phase is distributed between interstitial aerosol and ice particles in dependence on the temperature and ice surface, respectively. In cold cirrus clouds with small ice surface areas (T <205 K) the partitioning is strongly in favour of interstitial ternary solution particles while in warmer cirrus clouds with large ice surface areas the uptake on ice dominates. Consequently, denitrification via sedimenting ice particles may occur only in the -more frequently occurring- warm cirrus clouds
The HNO3 coverage on ice is found to be different for ice particles and ice films. On ice films the coverage can increase with decreasing temperature from about 0.1 to 0.8 monolayer, while that on ice particles is found to decrease with temperature and PHNO3 from 0.1 to 0.001 monolayer. An HNO3 uptake behaviour following dissociative Langmuir isotherms where the coverage decreases for descending temperatures may explain the observations for ice particles
From a comparison of the HNO3 measurements with model calculations it is found that (i) the global model of Lawrence and Crutzen (1998) overestimates the HNO3 partitioning in favour of the ice particles (ii) the Langmuir surface chemistry model of Tabazadeh et al. (1999) overestimates HNO3 coverages for temperatures ≤210 K More appropriate coverages are calculated when implementing in that model a temperature dependent function for the adsorption free energy (ΔGads (T)), which is empirically derived from the coverage measurements.
We examine the effect of nanometer-sized aircraft-induced aqueous sulfuric acid (H2SO4/H2O) particles on atmospheric ozone as a function of temperature. Our calculations are based on a previously derived parameterization for the regional-scale perturbations of the sulfate surface area density due to air traffic in the North Atlantic Flight Corridor (NAFC) and a chemical box model. We confirm large scale model results that at temperatures T>210 K additional ozone loss -- mainly caused by hydrolysis of BrONO2 and N2O5 -- scales in proportion with the aviation-produced increase of the background aerosol surface area. However, at lower temperatures (< 210 K) we isolate two effects which efficiently reduce the aircraft-induced perturbation: (1) background particles growth due to H2O and HNO3 uptake enhance scavenging losses of aviation-produced liquid particles and (2) the Kelvin effect efficiently limits chlorine activation on the small aircraft-induced droplets by reducing the solubility of chemically reacting species. These two effects lead to a substantial reduction of heterogeneous chemistry on aircraft-induced volatile aerosols under cold conditions. In contrast we find contrail ice particles to be potentially important for heterogeneous chlorine activation and reductions in ozone levels. These features have not been taken into consideration in previous global studies of the atmospheric impact of aviation. Therefore, to parameterize them in global chemistry and transport models, we propose the following parameterisation: scale the hydrolysis reactions by the aircraft-induced surface area increase, and neglect heterogeneous chlorine reactions on liquid plume particles but not on ice contrails and aircraft induced ice clouds.
This report has been prepared by the SETAC Europe Scientific Task Group on Global And RegionaL Impact Categories (SETAC-Europe/STG-GARLIC) that is installed by the 2nd SETAC Europe working group on life cycle impact assessment (WIA-2). This document is background to a chapter written by the same authors under the title “Climate change, stratospheric ozone depletion, photo-oxidant formation, acidification and eutrophication” in Udo de Haes et al. (2002). The chapter summarises the work of the STG-GARLIC and aims to give a state-of-the-art review of the best available practice(s) regarding category indicators and lists of concomitant characterisation factors for climate change, stratospheric ozone depletion, photo-oxidant formation, acidification, and aquatic and terrestrial eutrophication. Backgrounds on each of the specific impact categories are given in another background report from Klöpffer and Potting (2001).
This background report provides details on a selection of general issues relevant in relation to LCA and characterisation of impact in LCA. The document starts with a short introduction of the LCA methodology and impact assessment in LCA for non LCA-experts. LCA experts, on the other hand, will usually not be familiar in-depth with scientific and political backgrounds of the specific impact categories. A review of this is given. Also the discussion is provided about the issue of the position of the category indicator in the causality chain, and into the related issue of spatial differentiation. These two issues appeared to be one of the core items for SETAC-Europe/STG-GARLIC.
This thesis contributes to a better understanding of the effect of heterogeneous chemistry on ozone in the tropopause region. As part of the German research project ALTO, it especially focuses on the impact of aircraft emissions on heterogeneous ozone chemistry in this region. This is an important question as ozone is a strong greenhouse gas, whose radiative effect, is strongest near the tropopause.
In general, the treatment of heterogeneous processes on background and aviation-produced particles requires the consideration of processes ranging from nanometer to continental scale. For this reason the present modeling work includes a treatment of small scale processes as well as the development and subsequent application of parameterisations. Three numerical trajectory box models considering highly detailed microphysical and chemical processes have been developed: (a) an aircraft plume model including coagulation, chemistry and plume dilution, (b) a particle-size resolved microphysical box model and, (c) a comprehensive photo-chemical box model.
Currently, there are a lot of research activities dealing with gamma titanium aluminide (γ-TiAl) alloys as new materials for low pressure turbine (LPT) blades. Even though the scatter in mechanical properties of such intermetallic alloys is more distinctive as in conventional metallic alloys, stochastic investigations on γ -TiAl alloys are very rare. For this reason, we analyzed the scatter in static and dynamic mechanical properties of the cast alloy Ti-48Al-2Cr-2Nb. It was found that this alloy shows a size effect in strength which is less pronounced than the size effect of brittle materials. A weakest-link approach is enhanced for describing a scalable size effect under multiaxial stress states and implemented in a post processing tool for reliability analysis of real components. The presented approach is a first applicable reliability model for semi-brittle materials. The developed reliability tool was integrated into a multidisciplinary optimization of the geometry of a LPT blade. Some processes of the optimization were distributed in a wide area network, so that specialized tools for each discipline could be employed. The optimization results show that it is possible to increase the aerodynamic efficiency and the structural mechanics reliability at the same time, while ensuring the blade can be manufactured in an investment casting process.
Simulation of thermal behavior during friction stir welding process for predicting residual stresses
(2014)