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Università della Svizzera italiana

Policy evaluation: labour market liberalization, unemployment and second home construction : Evidence from Switzerland

Stricker, Luzius ; Maggi, Rico (Dir.)

Thèse de doctorat : Università della Svizzera italiana, 2020 ; 2020ECO010.

This thesis is composed of three different chapters focusing on labour market policies, unemployment and the construction industry. The analyses aim to contribute to the microeconomic theory, proving three different concepts of externally caused variations, affecting both, the labour market equilibrium and the production function. In detail, the first part analyses the employment effects of...

Université de Fribourg

MAcroecological Framework for Invasive Aliens (MAFIA): disentangling large-scale context dependence in biological invasions

Pyšek, Petr ; Bacher, Sven ; Kühn, Ingolf ; Novoa, Ana ; Catford, Jane A. ; Hulme, Philip E. ; Pergl, Jan ; Richardson, David M. ; Wilson, John R. U. ; Blackburn, Tim M.

In: NeoBiota, 2020, vol. 62, p. 407–461

Macroecology is the study of patterns, and the processes that determine those patterns, in the distribution and abundance of organisms at large scales, whether they be spatial (from hundreds of kilometres to global), temporal (from decades to centuries), and organismal (numbers of species or higher taxa). In the context of invasion ecology, macroecological studies include, for example,...

Université de Fribourg

Experimental tuning of transport regimes in hyperuniform disordered photonic materials

Aubry, Geoffroy J. ; Froufe-Pérez, Luis S. ; Kuhl, Ulrich ; Legrand, Olivier ; Scheffold, Frank ; Mortessagne, Fabrice

In: Physical Review Letters, 2020, vol. 125, no. 12, p. 127402

We present wave transport experiments in hyperuniform disordered arrays of cylinders with high dielectric permittivity. Using microwaves, we show that the same material can display transparency, photon diffusion, Anderson localization, or a full band gap, depending on the frequency ν of the electromagnetic wave. Interestingly, we find a second weaker band gap, which appears to be related to...

Università della Svizzera italiana

Towards spatially varying gloss reproduction for 3D printing

Piovarči, Michal ; Foshey, Michael ; Babaei, Vahid ; Rusinkiewicz, Szymon ; Matusik, Wojciech ; Didyk, Piotr

In: ACM transactions on graphics, 2020, vol. 39, no. 6, p. 13 p

3D printing technology is a powerful tool for manufacturing complex shapes with high-quality textures. Gloss, next to color and shape, is one of the most salient visual aspects of an object. Unfortunately, printing a wide range of spatially-varying gloss properties using state-of-the-art 3D printers is challenging as it relies on geometrical modifications to achieve the desired appearance. A...

Université de Fribourg

A monitoring system for spatiotemporal electrical self-potential measurements in cryospheric environments

Weigand, Maximilian ; Wagner, Florian M. ; Limbrock, Jonas K. ; Hilbich, Christin ; Hauck, Christian ; Kemna, Andreas

In: Geoscientific Instrumentation, Methods and Data Systems, 2020, vol. 9, no. 2020-2, p. 317–336

Climate-induced warming increasingly leads to degradation of high-alpine permafrost. In order to develop early warning systems for imminent slope destabilization, knowledge about hydrological flow processes in the subsurface is urgently needed. Due to the fast dynamics associated with slope failures, non- or minimally invasive methods are required for inexpensive and timely characterization...

Université de Fribourg

The importance of input data quality and quantity in climate field reconstructions – results from the assimilation of various tree-ring collections

Franke, Jörg ; Valler, Veronika ; Brönnimann, Stefan ; Neukom, Raphael ; Jaume-Santero, Fernando

In: Climate of the Past, 2020, vol. 16, no. 3, p. 1061–1074

Differences between paleoclimatic reconstructions are caused by two factors: the method and the input data. While many studies compare methods, we will focus in this study on the consequences of the input data choice in a state-of-the-art Kalman- filter paleoclimate data assimilation approach. We evaluate reconstruction quality in the 20th century based on three collections of tree-ring...

Università della Svizzera italiana

Parallel space-time multilevel methods with application to electrophysiology : theory and implementation

Benedusi, Pietro ; Krause, Rolf (Dir.)

Thèse de doctorat : Università della Svizzera italiana, 2020 ; 2020INFO005.

The goal of this thesis is to design and study an efficient strategy to solve possibly non-linear parabolic partial differential equations on massively parallel machines. Traditionally, when solving time-dependent problems, time stepping methods are used to advance the solution in time. These techniques are inherently sequential and therefore they introduce a bottleneck in the overall...

Université de Fribourg

Algal growth and weathering crust state drive variability in western Greenland Ice Sheet ice albedo

Tedstone, Andrew J. ; Cook, Joseph M. ; Williamson, Christopher J. ; Hofer, Stefan ; McCutcheon, Jenine ; Irvine-Fynn, Tristram ; Gribbin, Thomas ; Tranter, Martyn

In: The Cryosphere, 2020, vol. 14, no. 2, p. 521–538

One of the primary controls upon the melting of the Greenland Ice Sheet (GrIS) is albedo, a measure of how much solar radiation that hits a surface is reflected without being absorbed. Lower-albedo snow and ice surfaces therefore warm more quickly. There is a major difference in the albedo of snow-covered versus bare-ice surfaces, but observations also show that there is substantial spatio-...

Université de Fribourg

Detailed detection of active layer freeze-thaw dynamics using quasi-continuous electrical resistivity tomography (Deception Island, Antarctica)

Farzamian, Mohammad ; Vieira, Gonçalo ; Santos, Fernando A. Monteiro ; Tabar, Borhan Yaghoobi ; Hauck, Christian ; Paz, Maria Catarina ; Bernardo, Ivo ; Ramos, Miguel ; Pablo, Miguel Angel de

In: The Cryosphere, 2020, vol. 14, no. 3, p. 1105–1120

Climate-induced warming of permafrost soils is a global phenomenon, with regional and site-specific variations which are not fully understood. In this context, a 2-D automated electrical resistivity tomography (A-ERT) system was installed for the first time in Antarctica at Deception Island, associated to the existing Crater Lake site of the Circumpolar Active Layer Monitoring – South ...

Università della Svizzera italiana

The digital birth of an African city : the case of Douala

Pucciarelli, Marta ; Cantoni, Lorenzo (Dir.)

Thèse de doctorat : Università della Svizzera italiana, 2019 ; 2019COM003.

This dissertation focuses on the online communication and representation of a digital city in Africa: Douala, the largest city of the Republic of Cameroon. In particular, it explores the evolution of the web-based reproduction (Couclelis, 2004) of Douala, the largest city of the Republic of Cameroon, from a chronological, spatial and representational perspective, with the purpose of...