The Intensive Margin of Technology Adoption

We present a tractable model for analyzing the relationship between economic growth and the intensive and extensive margins of technology adoption. The "extensive" margin refers to the timing of a country's adoption of a new technology; the "intensive" margin refers to how many units are adopted (for a given size economy). At the aggregate level, our model is isomorphic to a neoclassical growth model, while at the microeconomic level it features adoption of firms at the extensive and the intensive margin. Based on a data set of 15 technologies and 166 countries our estimations of the model yield four main findings: (i) there are large cross-country differences in the intensive margin of adoption; (ii) differences in the intensive margin vary substantially across technologies; (iii) the cross-country dispersion of adoption lags has declined over time while the cross-country dispersion in the intensive margin has not; (iv) the cross- country variation in the intensive margin of adoption accounts for more than 40% of the variation in income per capita.Economic Growth, Technology Adoption, Cross-country studies.

Technology Diffusion:Measurement, Causes and Consequences

This chapter discusses different approaches pursued to explore three broad questions related to technology diffusion: what general patterns characterize the diffusion of technologies, and how have they changed over time; what are the key drivers of technology, and what are the macroeconomic consequences of technology. We prioritize in our dis- cussion unified approaches to these three questions that are based on direct measures of technolog

If Technology Has Arrived Everywhere, Why Has Income Diverged?

If Technology Has Arrived Everywhere, Why Has Income Diverged? We study the lags with which new technologies are adopted across countries, and their long-run penetration rates once they are adopted. Using data from the last two centuries, we document two new facts: there has been convergence in adoption lags between rich and poor countries, while there has been divergence in penetration rates. Using a model of adoption and growth, we show that these changes in the pattern of technology diffusion account for 80% of the Great Income Divergence between rich and poor countries since 1820

Technology Diffusion:Measurement, Causes and Consequences

This chapter discusses different approaches pursued to explore three broad questions related to technology diffusion: what general patterns characterize the diffusion of technologies, and how have they changed over time; what are the key drivers of technology, and what are the macroeconomic consequences of technology. We prioritize in our dis- cussion unified approaches to these three questions that are based on direct measures of technolog

If Technology Has Arrived Everywhere, Why Has Income Diverged?

If Technology Has Arrived Everywhere, Why Has Income Diverged? We study the lags with which new technologies are adopted across countries, and their long-run penetration rates once they are adopted. Using data from the last two centuries, we document two new facts: there has been convergence in adoption lags between rich and poor countries, while there has been divergence in penetration rates. Using a model of adoption and growth, we show that these changes in the pattern of technology diffusion account for 80% of the Great Income Divergence between rich and poor countries since 1820

Evolutionary Game Dynamics for Crowd Behavior in Emergency Evacuations

This paper studies the problem of a large group of individuals that has to get to a safety exit in the context of high-stress emergency evacuations. We model this problem as a discrete-state continuous-time game, where the players update their strategies to reach the exit within a defined time horizon, whilst avoiding undesirable situations such as congestion and being trampled. The proposed model builds on crowd dynamics in a two-strategy game theoretic context, which we extend to include aspects of crowd behavior originating in sociology and psychology, and in the analogous studies performed in immersive virtual environments. The main contribution of this paper is threefold: i) we propose a novel game formulation of the model in terms of the population distribution across three strategies, and provide a link with prospect theory; ii) we study the equilibria of the system and their stability via Lyapunov stability theory of nonlinear systems; iii) we extend the model to a multi-population setting, where each population represents the group of players at a certain distance from the exit

Uniformity of diet composition of Brown Skua chicks at different ages and between siblings

The diet of chicks may change according to their growth and also vary between siblings due to their competitive relationship. Diet composition of 81 Brown Skua (Stercorarius antarcticus lonnbergi) chicks was analysed from regurgitated stomach contents in order to determine changes in diet composition related to chick age and differences between siblings. Fifty-nine of the samples belonged to chicks whose age was estimated by applying culmen measurement to a regression function. The remaining 22 samples belonged to 11 sibling pairs whose stomach contents were simultaneously sampled. The diet was constituted mostly by soft tissues of penguins. Marine resources were a minor part of the diet of chicks, appearing in the third week of their life. The qualitative composition of the stomach content of siblings was similar in most cases, but mass of regurgitates differed between siblings (1.3– 90.0% = 0.5–9 g), which suggests the potential existence of aggressive food monopolization by one sibling, an issue to be elucidated with further research.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones Científicas y Técnica

Uniformity of diet composition of Brown Skua chicks at different ages and between siblings

The diet of chicks may change according to their growth and also vary between siblings due to their competitive relationship. Diet composition of 81 Brown Skua (Stercorarius antarcticus lonnbergi) chicks was analysed from regurgitated stomach contents in order to determine changes in diet composition related to chick age and differences between siblings. Fifty-nine of the samples belonged to chicks whose age was estimated by applying culmen measurement to a regression function. The remaining 22 samples belonged to 11 sibling pairs whose stomach contents were simultaneously sampled. The diet was constituted mostly by soft tissues of penguins. Marine resources were a minor part of the diet of chicks, appearing in the third week of their life. The qualitative composition of the stomach content of siblings was similar in most cases, but mass of regurgitates differed between siblings (1.3– 90.0% = 0.5–9 g), which suggests the potential existence of aggressive food monopolization by one sibling, an issue to be elucidated with further research.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones Científicas y Técnica

Millimeter-wave GaN-based HEMT development at ETH-Zürich

We review the AlGaN/GaN high electron mobility transistor (HEMT) activities in the Millimeter-Wave Electronics Group at ETH-Zürich. Our group's main thrust in the AlGaN/GaN arena is the extension of device bandwidth to higher frequency bands. We demonstrated surprising performances for AlGaN/GaN HEMTs grown on high-resistivity (HR) silicon (111) substrates, and extended cutoff frequencies of 100nm gate devices well into the millimeter (mm)-wave domain. Our results narrow the performance gap between GaN-on-SiC (or sapphire) and GaN-on-silicon and establish GaN-on-Si as a viable technology for low-cost mm-wave electronics. We here contrast the difference in behaviors observed in our laboratory between nominally identical devices built on high-resistivity silicon (HR-Si) and on sapphire substrates; we show high-speed devices with high-cutoff frequencies and breakdown voltages which combine fT,MAX×BV products as high as 5-10 THz V, and show AlGaN/GaN HEMTs with fT values exceeding 100GHz on HR-Si. Although the bulk of our activities have so far focused on AlGaN/GaN HEMTs on HR-Si, our process produces excellent device performances when applied to GaN HEMTs on SiC as well: 100nm gate transistors with fT>125GHz have been realized at ETH-Züric