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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.
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.
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.
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)
Mechanical properties and microstructure of heavy aluminum bonding wires for power applications
(2009)
Vorrichtung (1) zur Bestimmung eines TOC-Gehalts in einer wässrigen Lösung, die folgendes aufweist:- zumindest eine Ozonquelle (8) zur Erzeugung von Ozon in der wässrigen Lösung;- zumindest eine Strahlungsquelle (9) zur Bestrahlung der wässrigen Lösung mit UV-Strahlung;- eine Einrichtung (15) zur Bestimmung der elektrischen Leitfähigkeit der ozonierten und bestrahlten wässrigen Lösung.
This article analyzes how humanitarian and/or development organizations acting as intermediaries between scientists and vulnerable populations aim to make environmental changes visible while trying to meet local needs and demands for sustainable livelihoods. Based on an in-depth organizational case study in Southern Thailand, the research analyses the use of visualization tools to foster environmental knowledge and literacy while supporting both policymaking as well as citizen engagement. Drawing on insights from sociology of organizations, the study discusses the organizational reasons for the use of visualization tools, outlining the underlying coercive, mimetic and normative pressures that facilitate their proliferation in the context of environmental communication. The results show that both the participatory approach as well as the use of audiovisual and digital tools to communicate project goals and results have become indispensable and institutionalized tools in the organizational field of humanitarian and development aid. In this context, organizations have become intermediaries and translators between ‘climate risk’ scientists and ‘at risk’ people, thus, facilitating environmental communication. The results show that questions of trust and ownership of ideas play an important role in the context of livelihood related projects linked to climate change adaptation. In this context, not only does the style and content of communication, but also the relationship between the parties who communicate, have an impact upon the success or failure of managing options in climate change adaptation.
Only since the turn of the 21st century have humanitarian organisations developed specific strategies that address climate change impacts as a humanitarian challenge. Taking the International Red Cross / Red Crescent Movement, being the largest humanitarian network, as an empirical case study, the article discusses the Movement’s changes in the areas 1) agenda setting, 2) organisational restructuring, 3) networking, 4) programming, and 5) advocacy. Based on the case study and a theoretical framework of organisational sociology, the article provides conclusions on internal and external factors that can explain why the Movement has been successful in being one of the first actors within the organisational field of humanitarian organisations to focus systematically on the humanitarian implications of climatic changes.