The Invisible Processes Of Urban Design: A Qualitative Investigation Into The Dynamics Of Collective Decision-Making In Urban Development And Their Potential for Spatial Quality

In recent decades, the urban landscape of Switzerland has changed drastically and is now in sharp contrast to the ideals of planners and urban designers, such as the compact form of the Historical European City. Especially for the agglomeration areas, the call for a re-qualification of the built environment is strong, where spatial quality is still low from a planning and urban design viewpoint. In the thesis at hand, it is argued that the quality of the built environment is not failing mainly due to a lack of quality goals and imprecise normative concepts rather it fails because of scarce knowledge about the dynamics of spatially relevant decision-making. From a relational perspective, it becomes clear that content cannot be separated from process. Consequently, the important question is not what good spatial quality is, but how quality goals and normative concepts are embedded in and emerge through decision-making processes. This question addresses a hidden process on which conventional perspectives in the urban design field do not focus. In this cumulative dissertation, a place-making perspective is chosen in order to uncover the invisible processes of urban design. Consequently, the empirical investigation focuses on the analysis of the dynamics of local planning strategies and urban development projects in suburban and periurban areas in Switzerland and the identification of potentials for spatial quality. In particular, ten site developments in five municipalities were analyzed in-depth in order to comprehend the mechanisms of decision-making. The observed dynamics in turn served as entry points for the investigation of the robustness of spatial quality concepts. Three major tendencies in contemporary place-making have been identified: the lack of open decision-making forums and functional logics of thinking, the de-politicization of spatial quality debates and the tendency to fix quality goals. As a consequence of these mechanisms and their inherent logic of control, an intensified fragmentation of the already heterogeneous urban landscape in agglomeration areas has been observed. Since these fragmented landscapes are produced rather systematically, I propose not to condemn heterogeneity per se but to consider it as a potential guideline for spatial quality that addresses the locally grown structures. Finally, through the liberation from the logic of control, potentials both for a better qualification of existing urban landscapes and for the activation of spatially relevant actor-networks are opened up. One of the crucial elements of such a new planning and urban design ethos is the establishment of open forums, in which spatial quality is politicized and debated beyond formal political institutions and expert systems.In den letzten Jahrzehnten hat sich die Siedlungslandschaft der Schweiz drastisch verändert und steht heute im Widerspruch zu den Idealen von Planern und Städtebauern, wie z.B. die kompakte Form der Historischen Europäischen Stadt. Vor allem in den Agglomerationen ist der Ruf nach einer Re-Qualifizierung der gebauten Umwelt stark, wo die Siedlungsqualität aus der Sicht der genannten Disziplinen negativ beurteilt wird. In der vorliegenden Arbeit argumentiere ich, dass die Qualifizierung der bebauten Umwelt hauptsächlich nicht an fehlenden Qualitätszielen und unpräzisen normativen Konzepten scheitert, sondern am geringen Wissen über die Dynamik von raumrelevanten Entscheidungsprozessen. Aus einer relationalen Perspektive wird klar, dass Inhalt nicht von Prozess getrennt werden kann. Dementsprechend stellt sich in erster Linie nicht die Frage was gute Qualität ist, sondern wie Qualitätsziele in Entscheidungsprozessen eingebettet sind und wie sie handlungswirksam werden. Diese Frage verweist auf einen versteckten Prozess, der nicht im Vordergrund von herkömmlichen Betrachtungsweisen im Städtebau steht. Um die unsichtbaren Prozesse des Städtebaus aufzudecken, wurde für diese kumulative Dissertation entsprechend eine prozessorientierte place-making Perspektive gewählt. Konsequenterweise fokussiert die empirische Studie auf die Analyse von Dynamiken in lokalen Planungsstrategien und räumlichen Entwicklungsprojekten in suburbanen und periurbanen Gebieten in der Schweiz und die Identifikation von Potentialen für räumliche Qualität. Im Speziellen wurden zehn Arealentwicklungen in fünf Gemeinden tiefgehend analysiert, mit dem Ziel, die Mechanismen der Entscheidungsfindung zu verstehen. Die beobachteten Dynamiken dienten wiederum als Einstiegspunkte für die Studie von Robustheiten von Qualitätskriterien. Es konnten drei Tendenzen im heutigen place-making identifiziert werden: Das Fehlen von offenen Entscheidungsforen und funktionale Denklogiken, die De-Politisierung von Debatten über räumliche Qualität und die Tendenz, Qualitätsziele zu fixieren. Es wurde zudem beobachtet, dass diese Mechanismen und ihre inherente Logik der Kontrolle zu einer intensivierten Fragmentierung des ohnehin schon heterogenen Siedlungsraumes in Agglomerationen führen. Da dies in einer systematischen Art und Weise vonstatten geht, möchte ich vorschlagen, dass Heterogenität nicht per se verurteilt sondern als potentielle Leitlinie für räumliche Qualität gelesen wird, die lokal gewachsenen Strukturen mit aufnimmt. Potentiale für eine bessere Qualifizierung der Siedlungslandschaften und zu einer Aktivierung von raumrelevanten Akteur-Netzwerken ergeben sich schliesslich durch eine Befreiung von der Logik der Kontrolle, im Speziellen durch die Etablierung von offenen Foren, in der räumliche Qualität im Sinne einer breiten Debatte jenseits von formalen politischen Gremien und Expertensystemen politisiert und debattiert werden kann

Towards a proper assignment of systemic risk: the combined roles of network topology and shock characteristics

This proceeding at: European Conference on Complex Systems, took place 2013, setember, 16-20, in Barcelona (Spain).The 2007-2008 financial crisis solidified the consensus among policymakers that a macro-prudential approach to regulation and supervision should be adopted. The currently preferred policy option is the regulation of capital requirements, with the main focus on combating procyclicality and on identifying the banks that have a high systemic importance, those that are "too big to fail". Here we argue that the concept of systemic risk should include the analysis of the system as a whole and we explore systematically the most important properties for policy purposes of networks topology on resistance to shocks. In a thorough study going from analytical models to empirical data, we show two sharp transitions from safe to risky regimes: 1) diversification becomes harmful with just a small fraction (~2%) of the shocks sampled from a fat tailed shock distributions and 2) when large shocks are present a critical link density exists where an effective giant cluster forms and most firms become vulnerable. This threshold depends on the network topology, especially on modularity. Firm size heterogeneity has important but diverse effects that are heavily dependent on shock characteristics. Similarly, degree heterogeneity increases vulnerability only when shocks are directed at the most connected firms. Furthermore, by studying the structure of the core of the transnational corporation network from real data, we show that its stability could be clearly increased by removing some of the links with highest centrality betweeness. Our results provide a novel insight and arguments for policy makers to focus surveillance on the connections between firms, in addition to capital requirements directed at the nodes.his project was founded by ERA-Net on Complexity through grant RESINEE http://www.complexitynet.eu/Pages/default.aspx), by MINECO (Spain, http://www.mineco.gob.es/portal/site/mineco/) through grant PRODIEVO and by Comunidad de Madrid through grant MODELICO-CM (http://modelico.es/index.php/es/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Publicad

Conformations of large macrocycles and ring-in-ring complexes

This work was supported by the Swiss National Science Foundation.A kinetically directed, stepwise approach towards molecular Borromean links enabled the isolation and structural characterization of synthetic intermediates along the way. Here we report the synthesis and crystal structures of three flexible macrocyclic intermediates and a new ring-in-ring complex, anchored together through ruthenium(ii) centers, which contains open terpyridine caps in the inner Ring II. Terpyridines circumvent the conformational cis/trans limitations of bipyridines and the new ring-in-ring complex forms tetrametallic complexes with Zn(ii), Pt(ii) and Ru(iii) metal ions. Analysis of the four macrocyclic structures provides a good foundation for the conformational flexibility in these complexes and demonstrates the robust applicability of the terpyridine design elements towards the engineered synthesis of ring-in-ring topologies.Publisher PDFPeer reviewe

Wildfire selectivity for land cover type: does size matter ?

Previous research has shown that fires burn certain land cover types disproportionally to their abundance. We used quantile regression to study land cover proneness to fire as a function of fire size, under the hypothesis that they are inversely related, for all land cover types. Using five years of fire perimeters, we estimated conditional quantile functions for lower (avoidance) and upper (preference) quantiles of fire selectivity for five land cover types - annual crops, evergreen oak woodlands, eucalypt forests, pine forests and shrublands. The slope of significant regression quantiles describes the rate of change in fire selectivity (avoidance or preference) as a function of fire size. We used Monte-Carlo methods to randomly permutate fires in order to obtain a distribution of fire selectivity due to chance. This distribution was used to test the null hypotheses that 1) mean fire selectivity does not differ from that obtained by randomly relocating observed fire perimeters; 2) that land cover proneness to fire does not vary with fire size. Our results show that land cover proneness to fire is higher for shrublands and pine forests than for annual crops and evergreen oak woodlands. As fire size increases, selectivity decreases for all land cover types tested. Moreover, the rate of change in selectivity with fire size is higher for preference than for avoidance. Comparison between observed and randomized data led us to reject both null hypotheses tested (a = 0.05) and to conclude it is very unlikely the observed values of fire selectivity and change in selectivity with fire size are due to chance.Funding: This paper was supported by the Fundação para a Ciência e Tecnologia Ph.D. Grant SFRH/BD/40398/2007. JMCP participated in this research under the framework of research projects ‘‘Forest fire under climate, social and economic changes in Europe, the Mediterranean and other fire-affected areas of the world (FUME)’’, EC FP7 Grant Agreement No. 243888. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

Mind the bubbles: achieving stable measurements of maximum hydraulic conductivity through woody plant samples

The maximum specific hydraulic conductivity (kmax) of a plant sample is a measure of the ability of a plants’ vascular system to transport water and dissolved nutrients under optimum conditions. Precise measurements of kmax are needed in comparative studies of hydraulic conductivity, as well as for measuring the formation and repair of xylem embolisms. Unstable measurements of kmax are a common problem when measuring woody plant samples and it is commonly observed that kmax declines from initially high values, especially when positive water pressure is used to flush out embolisms. This study was designed to test five hypotheses that could potentially explain declines in kmax under positive pressure: (i) non-steady-state flow; (ii) swelling of pectin hydrogels in inter-vessel pit membranes; (iii) nucleation and coalescence of bubbles at constrictions in the xylem; (iv) physiological wounding responses; and (v) passive wounding responses, such as clogging of the xylem by debris. Prehydrated woody stems from Laurus nobilis (Lauraceae) and Encelia farinosa (Asteraceae) collected from plants grown in the Fullerton Arboretum in Southern California, were used to test these hypotheses using a xylem embolism meter (XYL'EM). Treatments included simultaneous measurements of stem inflow and outflow, enzyme inhibitors, stem-debarking, low water temperatures, different water degassing techniques, and varied concentrations of calcium, potassium, magnesium, and copper salts in aqueous measurement solutions. Stable measurements of kmax were observed at concentrations of calcium, potassium, and magnesium salts high enough to suppress bubble coalescence, as well as with deionized water that was degassed using a membrane contactor under strong vacuum. Bubble formation and coalescence under positive pressure in the xylem therefore appear to be the main cause for declining kmax values. Our findings suggest that degassing of water is essential for achieving stable and precise measurements of kmax through woody plant samples. For complete rehydration of woody samples, incubation in water under vacuum for 24 h is suggested as a reliable technique that avoids bubble problems associated with flushing under high positive pressure

Landscape - wildfire interactions in southern Europe: implications for landscape management

ReviewEvery year approximately half a million hectares of land are burned by wildfires in southern Europe, causing large ecological and socio-economic impacts. Climate and land use changes in the last decades have increased fire risk and danger. In this paper we review the available scientific knowledge on the relationships between landscape and wildfires in the Mediterranean region, with a focus on its application for defining landscape management guidelines and policies that could be adopted in order to promote landscapes with lower fire hazard. The main findings are that (1) socio-economic drivers have favoured land cover changes contributing to increasing fire hazard in the last decades, (2) large wildfires are becoming more frequent, (3) increased fire frequency is promoting homogeneous landscapes covered by fire-prone shrublands; (4) landscape planning to reduce fuel loads may be successful only if fire weather conditions are not extreme. The challenges to address these problems and the policy and landscape management responses that should be adopted are discussed, along with major knowledge gapsinfo:eu-repo/semantics/publishedVersio