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Rohdaten BfG-GNSS-Messnetz

Das BfG-GNSS-Messnetzes besteht aus über 50 GNSS-Stationen im Bereich der Nord- und Ostsee. Primärer Zweck ist die Georeferenzierung von Pegeln der Wasserstraßen- und Schifffahrtsverwaltung (WSV). Die Rohdaten umfassen die kontinuierlichen Beobachtungsdaten der Satellitensysteme GPS, Glonass, Galileo und Beidou. Der Höhenunterschied 'dH1' zwischen dem jeweiligen Referenzpunkt der GNSS-Antenne und den zugehörigen Pegelfestpunkten (PFP) kann dem Sitelog der Permanentstation entnommen werden. Der Sollhöhenunterschied 'dH2' zwischen den Pegelfestpunkten und dem Pegelnullpunkt (PNP) wird durch das zuständige Wasserstraßen- und Schifffahrtsamt geführt.

Umgang mit schwerkranken Füchsen in der Schonzeit

In dem Flyer wir beschrieben, wie mit schwerkranken Füchsen in der Schonzeit, umgegangen werden muß.

The global continental water budget using GRACE spaceborne gravimetry and high- resolution consistent geodetic-hydrometeorological data analysis

GRACE gravity measurements provide a direct measure of water storage changes over continents. Thus, this novel technique enables for the first time to close the continental water balance on large scales. We propose to use GRACE gravimetry to directly determine large scale actual evapotranspiration from ground-based measurements of precipitation and discharge on large basins. The project will also provide a previously not available direct determination of atmospheric moisture fluxes on large basins from storage changes and discharge. As such, it enables a novel evaluation of atmospheric model data. However, the anisotropic error structure of conventional GRACE products is limiting their utility even for the largest basins available. Hydrological quasi-signals appear in areas, e.g. deserts, where no signal exists. To this end, we develop a new approach to GRACE error modelling, that makes use of known mass changes and their uncertainties, derived from hydrological constraints for selected areas, e.g. with negligible inputs (deserts) or with negligible evapotranspiration (snow/ice -, high altitude regions). This strategy allows for a correction of the gravity signal beyond the conventional de-aliasing procedures and thus an improvement of resolution in terms of space, time and mass. The close interdisciplinary collaboration will ensure the establishment of GRACE as a reliable hydrological sensor. Our investigations of the characteristics of both the large scale actual evapotranspiration and the atmospheric moisture flux enable us to predict discharge from ungauged basins and to evaluate the corresponding uncertainty by use of GRACE data. The global coverage of data from gauged and ungauged basins will hence lead to an improved determination of the global continental and the respective atmospheric water budget with a minimum of model assumptions.

Solar Power from Space - European Strategy in the Light of Sustainable Development, Phase 1: Earth and Space Based Power Generation Systems

This study has to be understood in the frame of the global Energy Policy. A great part of world energy production is currently based on non-renewable sources: oil, gas and coal. Global warming and restricted fossil energy sources force a strong demand for another climate compatible energy supply. Therefore, fossil energy sources will nearly disappear until the end of this century. The question is to find a viable replacement. By using viable' it is meant a low-cost and environmental friendly energy. In other words, the question is to find an alternative to nuclear energy among all proposed but still not mature renewable energies. One of the solutions proposed is solar energy. Yet, two major concerns slow down its development as an alternative: first, it lacks of technological maturity and secondly it suffers from alternating supply during days and nights, winters and summers. The idea proposed by Glaser in the sixties to bypass this inconvenient is to take the energy at the source (or at least, as near as possible): in other words, to put a solar station on orbit that captures the energy without problems of climatic conditions and to redirect it through a beam to the ground. That is the concept of Solar Power Satellites. Its principal feasibility was shown by DOE / NASA in 1970 years studies (5 GW SPS in GEO). Project objectives: This phase 1 study activity is to be seen as the initial step of a series of investigations on the viability of power generation in space facing towards an European strategy on renewable, CO2 free energy generation, including a technology development roadmap pacing the way to establish in a step-wise approach on energy generation capabilities in space. The entire activity has to be embedded in an international network of competent, experienced partners. As part of this, an interrelationship to and incorporation of activities targeting the aims of the EU 6th FP ESSPERANS should be maintained. In particular, the activities related to following objectives are described: The generation of scientifically sound and objective results on terrestrial CO2 emission free power generation solutions in comparison with state-of-the-art space based solar power solutions The detailed comparison and trades between the terrestrial and the space based solutions in terms of cost, reliability and risk The identification of possible synergies between ground and space based power generation solutions The assessment on terrestrial energy storage needs by combining ground based with space based energy generation solutions The investigation of the viability of concepts in terms of energy balance of the complete systems and payback times.

FP5-EESD, Energieeffizienz und Nachhaltigkeit in nachgerüsteten und neuen Museumsgebäuden (MUSEUMS): Sanierungskonzept für das Herzog-Anton-Ulrich Museum in Braunschweig

Ziel des Forschungs- und Entwicklungsprojekts ist die Planung und Umsetzung eines integralen Energie- und Sanierungskonzepts für das 1887 in Braunschweig eröffnete Herzog-Anton-Ulrich-Museum. Unter Mitwirkung aller Projektbeteiligten werden die für die Sanierung relevanten Themengebiete Bauphysik, Raumklima, Heizung und Lüftung, Tages- und Kunstlicht untersucht. Der Einhaltung der für die Exponate maßgeblichen geringen Toleranzen in Bezug auf Feuchte und Temperatur kommt in diesem Zusammenhang besondere Bedeutung zu. Durch das Sanierungskonzept soll eine erhebliche Reduktion des Heizenergie- und elektrischen Stromverbrauchs erreicht werden (Heizenergie: - 35 Prozent, Strom für Beleuchtung, Belüftung und Befeuchtung: - 50 Prozent ). Weiterhin sollen die thermische und visuelle Behaglichkeit und die konservatorischen Randbedingungen für die Exponate verbessert werden. Dabei stehen eine Verbesserung der Gebäudehülle (Herstellung der Luftdichtheit, Einsatz optimierter Verglasungen etc.) und die Vermeidung sommerlicher Überhitzung im Vordergrund. Zur Umsetzung einer weitestgehend natürlichen Klimatisierung wird auch die Reaktivierung des vorhandenen Hypokausten-Systems geprüft. Die Konzepte werden seit Oktober 2000 durch Messungen und Computersimulationen geprüft und validiert. Nach der Sanierung folgt eine einjährige Monitoring- und Evaluierungsphase. Das Sanierungsprojekt für das Herzog-Anton-Ulrich Museum zeigt die vielfältigen Möglichkeiten, wie im behutsamen Umgang mit historischer Bausubstanz die klimatischen und visuellen Anforderungen an Museen optimiert und gleichzeitig erhebliche Energieeinsparungen realisiert werden können.

AURORa - Investigation of the Radar Backscatter of Rain Impinging on the Ocean Surface

Over land, observations of rain rates are more or less operational. To obtain information about precipitation at the coastal zones, weather radars are used. However, over the oceans, especially away from the main shipping routes, no direct precipitation measurements are performed. In these regions, satellite data can provide information about precipitation events. Satellites deploying passive and active microwave sensors can operate independently of cloud cover and time of day. Passive microwave sensors give crude estimates of rain rates over large areas but cannot resolve small-scale rain events of short duration as are often observed in the tropics, for example. Active microwave sensors with high resolutions, such as synthetic aperture radars can provide more reliable information. Though the effect of rain on the atmosphere is a very topical area of research, the radar backscattering mechanisms at the water surface during rain events combined with wind are still not well understood. The purpose of this project is to investigate the radar backscattering from the water surface in the presence of rain and wind in order to interpret satellite radar data produced by active microwave sensors. Furthermore, the results should be embedded into models of the radar backscattering from the water surface to allow for estimating rain rates by using satellite data. Research topics: Rain impinging on a water surfaces generates splash products including crowns, cavities, stalks and secondary drops, which do not propagate, and ring waves and subsurface turbulence. We are investigating this phenomena at the wind-wave tank of the University of Hamburg. The tank is fitted with an artificial rain simulator of 2.3 m2 area mounted 4.5 m over the water surface. Rain drops of 2.1 and 2.9 mm in diameter with rain rates up to 100 mm/h have been produced. Wind with speeds 10 m/s and monomolecular slicks act on the water surface. The influence of the rain on the water surface is measured with a resistance type wire gauge, a two dimensional laser slope gauge and an coherent 9.8 GHz (x band) continuous wave scatterometer operating at VV-, HH- and HV-polarization. The influence of rain below the water surface is measured with colored raindrops which are observed with a video camera to investigate the turbulent motion and the depth of the mixed layer. At the North Sea Port of Buesum in Germany, a scatterometer operating at all polarizations and five frequencies will be mounted during summer of this year. The radar backscatter of the sea surface during rain events will be measured in combination with meteorological observations. With help of these measurements, existing radar backscatter models of the water surface will be improved for the presence of rain events. To validate the improved models, ERS-2 SAR-images will be compared with weather radar data.

Schwerpunktprogramm (SPP) 1257: Massentransporte und Massenverteilungen im System Erde; Mass Transport and Mass Distribution in the Earth System, The global continental water balance using GRACE spaceborne gravimetry and high-resolution consistent geodetic-hydrometeorological data analysis - Phase 1-3

GRACE gravity measurements provide a direct measure of water storage changes over continents. As such, it enables---for the first time---to close the continental water balance on large scales, and a direct determination of actual evapotranspiration---the unknown component of water balance---from terrestrial precipitation and run-off measurements on large scales. Atmospheric moisture flux offers another independent way of determining water storage changes, where there is no need for evapotranspiration information. This allows for a mutual inter-comparison of data from three independent disciplines and an evaluation of hydrological and atmospheric models. Thus the overall objectives of the project are 1. the direct analysis of large-scale water balances, and 2. the quantification of related uncertainties for large catchment areas in different climatic zones. In order to achieve consistent water balances, the mass change rates from GRACE, hydrology, and hydrometeorology have to be evaluated with respect to natural fluctuations and intrinsic errors. Statistical investigations are needed to characterize the respective contributions. Current results: Mass change estimates from GRACE are more accurate for large catchments (deeper 250,000 sq. km.) than for small catchments. 1. Vertically integrated moisture flux divergences from regional and global atmospheric models provide valuable constraints for estimating mass changes from GRACE. 2. A comparison of GRACE with hydrology datasets indicates that there is a sizeable amount of outliers in GRACE. These outliers have to be removed before any analysis can be done with the GRACE data. 3. Satellite RADAR altimetry provides estimates of runoff from catchments, where in situ measurements are not available, which helps in the validation and evaluation of GRACE derived mass change estimates.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Sea Ice Deformation Mapping by Means of Synthetic Aperture Radar

A concept that utilizes parameters retrieved from synthetic aperture radar (SAR) imagery will be devised in order to evaluate the atmospheric drag coefficient of sea ice. Methods will be developed for mapping and quantifying sea ice surface structure and deformation (e. g. floe size distribution, ridge spacing) from radar data. Considering that different SAR systems will be launched into space in the near future, the proposed investigations consider the effect of radar frequency, polarization, and spatial resolutions on the parameter retrieval. Retrieval methods and their accuracy will be assessed. Potential correlations between SAR backscatter variations, retrieved parameters related to sea ice deformation and surface structure, and the atmospheric drag coefficient will be analysed. The utilization of the retrieved parameters will be tested in numerical simulations of atmospheric boundary layer processes. Quantitative information about the sea ice surface structure and deformation is also of use for modelling sea ice dynamics, estimating sea ice mass balance, classifying ice types, and for safety and efficiency of marine transport and offshore operations.

Chemische Fernorientierung bei Parasitoiden samenfressender Wirte: Signale, Reichweite der Signale und Mechanismen der Fernorientierung

Die Untersuchung der chemischen Signale multitrophischer Systeme stellt momentan einen Schwerpunkt der ökologischen Forschung dar. Allerdings gibt es bislang kaum Untersuchungen für tritrophische Systeme aus Samen, samenfressenden Insekten und deren natürlichen Feinden, z.B. Parasitoiden. Im Rahmen des geplanten Projektes sollen erstmals für ein solches System die chemischen Signale identifiziert werden, die von Samen (bzw. Körnern) abgegeben werden und von Parasitoiden bei der Wirtssuche genutzt werden. Die Ergebnisse sollen die Aufmerksamkeit auf die bislang vernachlässigte Chemische Ökologie dieser Systeme lenken und die Grundlage für weitere Arbeiten in diesem Bereich schaffen. Darüber hinaus sollen an dem untersuchten System exemplarisch erstmals die Verhaltensweisen von Parasitoiden bei der Fernorientierung in Abwesenheit von Luftbewegungen analysiert und der sogenannte active space von chemischen Signalen unter diesen Bedingungen theoretisch und experimentell bestimmt werden. Die Ergebnisse des Projektes werden zum grundlegenden Verständnis multitrophischer Systeme beitragen und sind in der Biologischen Schädlingsbekämpfung von Bedeutung, z.B. bei der Festlegung der Anzahl und Abstände von Freilassungsorten von Parasitoiden.

Litebus-Modular Lightweight Sandwich Bus Concept

Objective: Increasing awareness by the public opinion about environmental issues, energy and material conservation at all stages of product life (from raw materials to disposal/recycling) is putting the industry in general and the transport industry in particular under increased pressure to reduce CO2 emissions and save energy. Environmental protection and safety will be increasingly influenced by legislation. The European transport industry is estimated to generate 22 percent of the carbon dioxide emission. As the car population is expected to grow 40 percent by the year 2010 new tough targets for reducing emissions by 30 percent in 2010 are being set by the EU, against the state of the art technologies of 1995. It is generally agreed by the industry that reductions of this size will require a change in current technologies. Multi-material technology (sandwich and/or hybrid materials) is becoming increasingly important in new vehicle design. Public service vehicles (buses and coaches) are regarded as primary targets for application of sandwich construction and multi-materials. Public service vehicles (PSV) play a major role in the transportation industry of both industrialized and developing countries. The proposed project will be focused on the development of a novel technology to manufacture bus/coach bodies using sandwich multi-material panels. The main overall objectives of the project are: - Solving the problem of reducing weight and production costs of land transport vehicles through the development of a technology of modular bus/coach construction, using 'all composite' multi-material sandwich panels instead of steel/aluminium space frame lined with sheets of different materials. - Devise design methodologies that reduce production lead time through reduction of number of components, functional integration, and allowance for dismantling, easy repair and recycling. Primce Contractor: INEGI - Instituto de Engenharia Mecanica e Gestao Industrial, Leca do Balio, Portugal.

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