The Geoff Egan Memorial Lecture 2011. Artefacts, art and artifice: reconsidering iconographic sources for archaeological objects in early modern Europe

A first systematic analysis of historic domestic material culture depicted in contemporaneous Western painting and prints, c.1400-1800. Drawing on an extensive data set, the paper proposes to methodologies and hermeneutics for historical analysis and archaeological correspondence

A complex geo-scientific strategy for landslide hazard mitigation ? from airborne mapping to ground monitoring

International audienceAfter a large landslide event in Sibratsgfäll/Austria several exploration methods were evaluated on their applicability to investigate and monitor landslide areas. The resulting optimised strategy consists of the combined application of airborne electromagnetics, ground geoelectrical measurements and geoelectrical monitoring combined with hydrological and geological mapping and geotechnical modelling. Interdisciplinary communication and discussion was the primary key to assess this complicated hazard situation

Non-parametric modeling of the intra-cluster gas using APEX-SZ bolometer imaging data

We demonstrate the usability of mm-wavelength imaging data obtained from the APEX-SZ bolometer array to derive the radial temperature profile of the hot intra-cluster gas out to radius r_500 and beyond. The goal is to study the physical properties of the intra-cluster gas by using a non-parametric de-projection method that is, aside from the assumption of spherical symmetry, free from modeling bias. We use publicly available X-ray imaging data from the XMM-Newton observatory and our Sunyaev-Zel'dovich Effect (SZE) imaging data from the APEX-SZ experiment at 150 GHz to de-project the density and temperature profiles for the relaxed cluster Abell 2204. We derive the gas density, temperature and entropy profiles assuming spherical symmetry, and obtain the total mass profile under the assumption of hydrostatic equilibrium. For comparison with X-ray spectroscopic temperature models, a re-analysis of the recent Chandra observation is done with the latest calibration updates. Using the non-parametric modeling we demonstrate a decrease of gas temperature in the cluster outskirts, and also measure the gas entropy profile. These results are obtained for the first time independently of X-ray spectroscopy, using SZE and X-ray imaging data. The contribution of the SZE systematic uncertainties in measuring T_e at large radii is shown to be small compared to the Chandra systematic spectroscopic errors. The upper limit on M_200 derived from the non-parametric method is consistent with the NFW model prediction from weak lensing analysis.Comment: Replaced with the published version; A&A 519, A29 (2010

Birth and fate of hot-Neptune planets

This paper presents a consistent description of the formation and the subsequent evolution of gaseous planets, with special attention to short-period, low-mass hot-Neptune planets characteristic of $\mu$ Ara-like systems. We show that core accretion including migration and disk evolution and subsequent evolution taking into account irradiation and evaporation provide a viable formation mechanism for this type of strongly irradiated light planets. At an orbital distance $a \simeq$ 0.1 AU, this revised core accretion model leads to the formation of planets with total masses ranging from $\sim$ 14 \mearth (0.044 \mjup) to $\sim$ 400 \mearth (1.25 \mjup). The newly born planets have a dense core of $\sim$ 6 \mearth, independent of the total mass, and heavy element enrichments in the envelope, $M_{\rm Z,env}/M_{\rm env}$, varying from 10% to 80% from the largest to the smallest planets. We examine the dependence of the evolution of the born planet on the evaporation rate due to the incident XUV stellar flux. In order to reach a $\mu$ Ara-like mass ($\sim$ 14 \mearth) after $\sim$ 1 Gyr, the initial planet mass must range from 166 \mearth ($\sim$ 0.52 \mjup) to about 20 \mearth, for evaporation rates varying by 2 orders of magnitude, corresponding to 90% to 20% mass loss during evolution. The presence of a core and heavy elements in the envelope affects appreciably the structure and the evolution of the planet and yields $\sim 8$ difference in radius compared to coreless objects of solar composition for Saturn-mass planets. These combinations of evaporation rates and internal compositions translate into different detection probabilities, and thus different statistical distributions for hot-Neptunes and hot-Jupiters.Comment: 4 figures, accepted for publication in Astronomy and Astrophysic

An Experimental Comparison of Robust Control Algorithms On a Direct Drive Manipulator

In this paper we present an experimental comparison of recent passivity based robust control algorithms on a two link direct drive robot arm. The manipulator is actuated with high torque brushless DC motors and is controlled by a DSP development system interfaced to a PC486 workstation. Four algorithms are compared with respect to ease of design, implementation, and performance of the closed loop systems. 1 Introduction In this paper we summarize the results of a systematic comparison of passivity based robust control algorithms on the two--link direct drive robot manipulator shown below in Figure (1). Four algorithms are compared with respect to ease of design, implementation, and performance of the closed--loop system. The reader is referred to the report [5] for the complete study, which also includes data for additional algorithms beyond those presented here. The manipulator used in the study, known as D2R2, was constructed with Compumotor Model DM1015-B brushless DC motors, contr..

Geotechnische Erkundung und Standsicherheitskriterien Bergwerk Gorleben. Teilprojekt 1 Abschlussbericht

TIB Hannover: FR 3446(Schl1)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman