33 research outputs found
Spatially continuous snow depth mapping by aeroplane photogrammetry for annual peak of winter from 2017 to 2021 in open areas
Information on snow depth and its spatial distribution is important for
numerous applications, including natural hazard management, snow water
equivalent estimation for hydropower, the study of the distribution and
evolution of flora and fauna, and the validation of snow hydrological
models. Due to its heterogeneity and complexity, specific remote sensing
tools are required to accurately map the snow depth distribution in Alpine
terrain. To cover large areas (>100 km2),
airborne laser scanning (ALS) or aerial photogrammetry with large-format
cameras is needed. While both systems require piloted aircraft for data
acquisition, ALS is typically more expensive than photogrammetry but yields
better results in forested terrain. While photogrammetry is slightly
cheaper, it is limited due to its dependency on favourable acquisition
conditions (weather, light conditions). In this study, we present
photogrammetrically processed high-spatial-resolution (0.5 m) annual snow
depth maps, recorded during the peak of winter over a 5-year period under
different acquisition conditions over a study area around Davos,
Switzerland. Compared to previously carried out studies, using the Vexcel
UltraCam Eagle Mark 3 (M3) sensor improves the average ground sampling distance to
0.1 m at similar flight altitudes above ground. This allows for very
detailed snow depth maps in open areas, calculated by subtracting a snow-off
digital terrain model (DTM, acquired with ALS) from the snow-on digital
surface models (DSMs) processed from the airborne imagery. Despite
challenging acquisition conditions during the recording of the UltraCam
images (clouds, shaded areas and fresh snow), 99 % of unforested areas
were successfully photogrammetrically reconstructed. We applied masks (high
vegetation, settlements, water, glaciers) to increase the reliability of the
snow depth calculations. An extensive accuracy assessment was carried out
using check points, the comparison to DSMs derived from unpiloted aerial
systems and the comparison of snow-free DSM pixels to the ALS DTM. The
results show a root mean square error of approximately 0.25 m for the
UltraCam X and 0.15 m for the successor, the UltraCam Eagle M3. We developed
a consistent and reliable photogrammetric workflow for accurate snow depth
distribution mapping over large regions, capable of analysing snow
distribution in complex terrain. This enables more detailed investigations
on seasonal snow dynamics and can be used for numerous applications related
to snow depth distribution, as well as serving as a ground reference for new
modelling approaches and satellite-based snow depth mapping.</p
Intertwining personal and reward relevance: evidence from the drift-diffusion model.
In their seminal paper 'Is our self nothing but reward', Northoff and Hayes (Biol Psychiatry 69(11):1019-1025, Northoff, Hayes, Biological Psychiatry 69(11):1019-1025, 2011) proposed three models of the relationship between self and reward and opened a continuing debate about how these different fields can be linked. To date, none of the proposed models received strong empirical support. The present study tested common and distinct effects of personal relevance and reward values by de-componenting different stages of perceptual decision making using a drift-diffusion approach. We employed a recently developed associative matching paradigm where participants (N = 40) formed mental associations between five geometric shapes and five labels referring personal relevance in the personal task, or five shape-label pairings with different reward values in the reward task and then performed a matching task by indicating whether a displayed shape-label pairing was correct or incorrect. We found that common effects of personal relevance and monetary reward were manifested in the facilitation of behavioural performance for high personal relevance and high reward value as socially important signals. The differential effects between personal and monetary relevance reflected non-decisional time in a perceptual decision process, and task-specific prioritization of stimuli. Our findings support the parallel processing model (Northoff & Hayes, Biol Psychiatry 69(11):1019-1025, Northoff, Hayes, Biological Psychiatry 69(11):1019-1025, 2011) and suggest that self-specific processing occurs in parallel with high reward processing. Limitations and further directions are discussed
Stereotactic LINAC radiosurgery for the treatment of patients with glomus jugulare tumors
Präoperative Lokalisationsdiagnostik und operative Ergebnisse bei 411 pHPT Operationen an einer Klinik für Endokrine Chirurgie
Differential effects of NMDA and AMPA glutamate receptors on functional magnetic resonance imaging signals and evoked neuronal activity during forepaw stimulation of the rat
Copyright © 2006 by the Society for Neuroscienc
Successful deep brain stimulation of the nucleus accumbens in severe alcohol dependence is associated with changed performance monitoring
Item does not contain fulltextFollowing recent advances in neuromodulation therapy for mental disorders, we treated one patient with severe alcohol addiction with deep brain stimulation (DBS) of the nucleus accumbens (NAc). Before and one year following the surgery, we assessed the effects of DBS within the NAc on the addiction as well as on psychometric scores and electrophysiological measures of cognitive control. In our patient, DBS achieved normalization of addictive behavior and craving. An electrophysiological marker of error processing (the error-related negativity) linked to anterior midcingulate cortex (aMCC) functioning was altered through DBS, an effect that could be reversed by periods without
stimulation. Thus, this case supports the hypothesis that DBS of the NAc could have a positive effect on addiction trough a normalization of craving associated with aMCC dysfunction