Urban Resilience Discourse Analysis: Towards a Multi-Level Approach to Cities

This study aims to understand the current state of research in urban resilience, its relations to urban sustainability and to integrate several distinct approaches into a multi-level perspective of cities comprising micro, meso and macro levels and their interactions. In fact, based on the meta-analysis of nearly 800 papers from Scopus from 1973 to 2018, we show that urban resilience discourses address micro and meso levels, considering shocks of bottom-up origin such as natural disasters. In contrast, the regional resilience approach addresses meso and macro levels (regional and global scales), considering shocks of top-down origin such as world economic crises. We find these approaches complementary and argue that in order to expand the urban resilience theory and overcome its limitations, they should be combined. For that purpose we propose a multi-level perspective that integrates both top-down and bottom-up dynamic processes. We argue that urban resilience is shaped by the synchronicity of adaptive cycles on three levels: micro, meso and macro. To build the multi-level approach of dynamics of adaptive cycles we use the panarchy framework

Thermal Analysis of EPOS components

We present a simulation study of the thermal behaviour of essential parts of the electron-positron converter of the positron source EPOS at the Research Center Dresden-Rossendorf. The positron moderator foil and the upper tube element of the electrostatic extraction einzellens are directly exposed to the primary electron beam (40 MeV, 40 kW). Thus, it was necessary to prove by sophisticated simulations that the construction can stand the evolving temperatures. It was found that thin moderator foils (< 20...40 µm) will not show a too strong heating. Moreover, the temperature can be varied in a wide range by choosing an appropriate thickness. Thus, the radiation-induced lattice defects can at least partly be annealed during operation. The wall of the extraction lens which is made from a stainless steel tube must be distinctly thinned to avoid damage temperatures. The simulations were performed time dependent. We found that the critical parts reach their final temperature after less than a minute