45 research outputs found

    The Psychology of Driving on Rural Roads: Development and Testing of a Model

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    Rural roads constitute the most dangerous road category with regard to the number of fatal accidents. In order to increase traffic safety on rural roads it is necessary to take into account not only their inherent properties but also their effect on behaviour. Gert Weller develops a psychological model for driving on rural roads which is validated in three empirical steps: laboratory, simulator and driving experiments. His results provide insight into the possibilities of how driving behaviour on rural roads can be influenced and give practical guidance for the enhancement of rural road safety. The book is written for psychologists in the fields of traffic psychology and human factors research, traffic engineers, road planners as well as for political decision makers in traffic planning departments.:1. Driving on Rural Roads: The Current Situation 2. Applying Existing Models to Driving on Rural Roads 2.1. A Framework 2.2. Individual Differences: Traits and Demographic Variables 2.3. Driving as a Self-Paced Task: Motivational Models 2.4. Perception and Information-Processing 3. A Psychological Model for Driving on Rural Roads 4. Empirical Validation 4.1. Overview and General Course of Events 4.2. The Laboratory Study: The Role of Perceived Road Characteristics 4.3. The Simulator Study: The Role of Cues and Affordances 4.4. On-the-Road Driving Tests: Behaviour and Accidents 5. Empirical Validation: Summary and Conclusion

    Combining clustering and abundances of galaxy clusters to test cosmology and primordial non-Gaussianity

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    We present the clustering of galaxy clusters as a useful addition to the common set of cosmological observables. The clustering of clusters probes the large-scale structure of the Universe, extending galaxy clustering analysis to the high-peak, high-bias regime. Clustering of galaxy clusters complements the traditional cluster number counts and observable-mass relation analyses, significantly improving their constraining power by breaking existing calibration degeneracies. We use the maxBCG galaxy clusters catalogue to constrain cosmological parameters and cross-calibrate the mass-observable relation, using cluster abundances in richness bins and weak-lensing mass estimates. We then add the redshift-space power spectrum of the sample, including an effective modelling of the weakly non-linear contribution and allowing for an arbitrary photometric redshift smoothing. The inclusion of the power spectrum data allows for an improved self-calibration of the scaling relation. We find that the inclusion of the power spectrum typically brings a 50\sim 50 per cent improvement in the errors on the fluctuation amplitude σ8\sigma_8 and the matter density Ωm\Omega_{\mathrm{m}}. Finally, we apply this method to constrain models of the early universe through the amount of primordial non-Gaussianity of the local type, using both the variation in the halo mass function and the variation in the cluster bias. We find a constraint on the amount of skewness fNL=12±157f_{\mathrm{NL}} = 12 \pm 157 (1σ1\sigma) from the cluster data alone.Comment: 12 pages, 10 figures, 2 tables. Minor changes to match published version on MNRA

    Neumayer III and Kohnen Station in Antarctica operated by the Alfred Wegener Institute

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    The Alfred Wegener Institute operates two stations in Dronning Maud Land, Antarctica. The German overwintering station Neumayer III is located on the Ekström Ice Shelf at 70°40’S and 08°16’W and is the logistics base for three long-term observatories (meteorology, air chemistry and geophysics) and nearby research activities. Due to the vicinity to the coast (ca. 20 km from the ice shelf edge), the Neumayer III Station is the junction for many German Antarctic expeditions, especially as the starting point for the supply traverse for the second German station Kohnen.The summer station Kohnen is located about 600 km from the coast and 750 km from Neumayer III Station on the Antarctic plateau at 75°S and 00°04’E. It was erected as the base for the deep-drilling ice core project, which took place between 2001 and 2006. Since then Kohnen Station is used as a logistics base for different research projects

    Fahreignung älterer Pkw-Fahrer

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    FAHREIGNUNG ÄLTERER PKW-FAHRER Fahreignung älterer Pkw-Fahrer / Weller, Gert (Rights reserved) ( -

    Characterization of long-term and seasonal variations of black carbon (BC) concentrations at Neumayer, Antarctica

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    Continuous black carbon (BC) observations were conducted from 1999 through 2009 by an Aethalometer (AE10) and from 2006 through 2011 by a Multi-Angle Absorption Photometer (MAAP) at Neumayer Station (NM) under stringent contamination control. Considering the respective observation period, BC concentrations measured by the MAAP were somewhat higher (median ± standard deviation: 2.1±2.0 ng m-3) compared to the AE10 results (1.6±2.1 ng m-3). Neither for the AE10 nor for the MAAP data set a significant long-term trend could be detected. Consistently a pronounced seasonality was observed with both instruments showing a primary annual maximum between October and November and a minimum in April with a maximum/minimum ratio of 4.5/1.6 = 3.8 and 2.7/0.64 = 4.2 for the MAAP and AE10 data, respectively. Occasionally a secondary summer maximum in January/February was visible. With the aim to assess the impact of BC on optical properties of the aerosol at NM, we evaluated the BC data along with particle scattering coefficients measured by an integrating nephelometer. We found the mean single scattering albedo of omega550 = 0.992±0.0090 (median: 0.994) at a wavelength of 550 nm with a range of values from 0.95 to 1.0
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