Stable discontinuous Galerkin FEM without penalty parameters

We propose a modified local discontinuous Galerkin (LDG) method for second--order elliptic problems that does not require extrinsic penalization to ensure stability. Stability is instead achieved by showing a discrete Poincar\'e--Friedrichs inequality for the discrete gradient that employs a lifting of the jumps with one polynomial degree higher than the scalar approximation space. Our analysis covers rather general simplicial meshes with the possibility of hanging nodes.Comment: Accepted for publication in the conference proceedings of Numerical Mathematics and Advanced Applications ENUMATH 2015. Typo correcte

Active Decisions and Pro-social Behavior: A Field Experiment on Blood Donation

In this paper, we propose a decision framework where people are individually asked to either actively consent or dissent to some pro-social behavior. We hypothesize that confronting individuals with the choice of engaging in a specific pro-social behavior contributes to the formation of issue-specific altruistic preferences while simultaneously involving a commitment. The hypothesis is tested in a large-scale field experiment on blood donation. We find that this "active-decision" intervention substantially increases the actual donation behavior of people who have not fully formed preferences beforehand.active decision, pro-social behavior, field experiment, blood donation

Debris Flows at the River Mletis Khevi (Greater Caucasus Mountains, Georgia) and its Assessment Methods

The erosional debris flow processes on the right side of the riverbed of Mletis-Khevi, a tributary of the Tetri Aragvi, are assessed on the basis of field and laboratory studies. The values of the mountain slope erosion in the Mletis-Khevi catchment area have been determined on the basis of field studies, taking into account the time factor and the extent of slope damage. Dependences are derived by means of the maximum discharge of debris flow of various intensities. Furthermore the volume of transported debris flow mass is calculated. A physical-mechanical and chemical analysis of the debris flow mass has been carried out in the laboratory. The results can be used at a subsequent stage for predicting the various basic characteristics of debris flows. --debris flow,discharge,erosion coefficient,catchment area