Chilean Export Performance: the Rol of Intensive and Extensive Margins

The paper presents a detailed description of the evolution of non-copper exports in the 1990-2007 period and decomposes its evolution in terms of the intensive and extensive margins. I document a significant export diversification in terms of markets and products. In the product dimension, diversification has occurred both for overall exports but also within the main exporting markets. In addition, the decomposition of exports growth into intensive margin (persistent exports) and extensive margins (new exports) indicates that export growth at the extensive margin contributed significantly to overall non-copper export growth, and particularly in the first half of the period.

On the conservation of distance in international trade

The volume of world trade has grown more than twice as fast as real world income since 1980. Surprisingly, the effect of distance on trade has increased during this period. It could be that countries are trading greater volumes of goods that are highly sensitive to distance. An alternative explanation is that distance has become more import for a significant share of goods. Using highly disaggregated bilateral trade data, the authors find that adjustment in the composition of trade has not influenced the way in which distance affects trade. In contrast, for about 25 percent of industries, distance has become more important. This implies that the increased distance sensitivity of trade is a result of a change in relative trade costs that affects many industries, as opposed to a shift to more distance-sensitive products. The authors also find that homogeneous products are twice as likely to have become more distance sensitive as compared with differentiated goods. This is consistent with the hypothesis that falling search costs, resulting from improvements in transport and communications, are relatively more important for differentiated goods. The results offer no evidence of the"death of distance."Rather, they suggest that distance-related relative trade costs have remained unchanged or shifted in favor of proximate markets.Economic Theory&Research,Environmental Economics&Policies,Standards and Technical Regulations,Common Carriers Industry,Trade Policy,Common Carriers Industry,Economic Theory&Research,TF054105-DONOR FUNDED OPERATIONADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Environmental Economics&Policies,Trade Policy

Delaying the Bell: The Effects of Longer School Days on Adolescent Motherhood in Chile

We analyze the effect of a Chilean school reform that lengthened the school day from half to full-day shifts on the likelihood that adolescent girls become mothers. By increasing the number of hours spent in school, the reform curtails opportunities to engage in risky sexual behaviors. Using Chile's socio-economic household surveys and administrative data from the Ministry of Education from 1990–2006, we exploit the exogenous time and regional variation in the implementation of the reform to identify the effects of increased education and adult supervision on the likelihood that adolescent girls become mothers. We find that access to full-day schools reduces the probability of becoming an adolescent mother among poor families and in urban areas: an increase in full-day municipal enrollment of 20% reduces the likelihood of teen motherhood by 5%.adolescent motherhood, adolescent pregnancy, school day reform, Chile

Overload depending on driving experience and situation complexity: which strategies faced with a pedestrian crossing?

The purpose of this study was to identify the influence of situation complexity and driving experience on subjective workload and driving performance, and the less costly and the most effective strategies faced with a hazard pedestrian crossing. Four groups of young drivers (15 traditionally trained novices, 12 early-trained novices, 15 with three years of experience and 15 with a minimum of five years of experience) were randomly assigned to three situations (simple, moderately complex and very complex) including unexpected pedestrian crossings, in a driving simulator. The subjective workload was collected by the NASA-TLX questionnaire after each situation. The main results confirmed that the situation complexity and the lack of experience increased the subjective workload. Moreover, the subjective workload, the avoidance strategies and the reaction times influenced the number of collisions depending on situation complexity and driving experience. These results must be taken into account to target the prevention actions

Strain integration and performance optimization in sub-20nm FDSOI CMOS technology

La technologie CMOS à base de Silicium complètement déserté sur isolant (FDSOI) est considérée comme une option privilégiée pour les applications à faible consommation telles que les applications mobiles ou les objets connectés. Elle doit cela à son architecture garantissant un excellent comportement électrostatique des transistors ainsi qu'à l'intégration de canaux contraints améliorant la mobilité des porteurs. Ce travail de thèse explore des solutions innovantes en FDSOI pour nœuds 20nm et en deçà, comprenant l'ingénierie de la contrainte mécanique à travers des études sur les matériaux, les dispositifs, les procédés d'intégration et les dessins des circuits. Des simulations mécaniques, caractérisations physiques (µRaman), et intégrations expérimentales de canaux contraints (sSOI, SiGe) ou de procédés générant de la contrainte (nitrure, fluage de l'oxyde enterré) nous permettent d'apporter des recommandations pour la technologie et le dessin physique des transistors en FDSOI. Dans ce travail de thèse, nous avons étudié le transport dans les dispositifs à canal court, ce qui nous a amené à proposer une méthode originale pour extraire simultanément la mobilité des porteurs et la résistance d'accès. Nous mettons ainsi en évidence la sensibilité de la résistance d'accès à la contrainte que ce soit pour des transistors FDSOI ou nanofils. Nous mettons en évidence et modélisons la relaxation de la contrainte dans le SiGe apparaissant lors de la gravure des motifs et causant des effets géométriques (LLE) dans les technologies FDSOI avancées. Nous proposons des solutions de type dessin ainsi que des solutions technologiques afin d'améliorer la performance des cellules standard digitales et de mémoire vive statique (SRAM). En particulier, nous démontrons l'efficacité d'une isolation duale pour la gestion de la contrainte et l'extension de la capacité de polarisation arrière, qui un atout majeur de la technologie FDSOI. Enfin, la technologie 3D séquentielle rend possible la polarisation arrière en régime dynamique, à travers une co-optimisation dessin/technologie (DTCO).The Ultra-Thin Body and Buried oxide Fully Depleted Silicon On Insulator (UTBB FDSOI) CMOS technology has been demonstrated to be highly efficient for low power and low leakage applications such as mobile, internet of things or wearable. This is mainly due to the excellent electrostatics in the transistor and the successful integration of strained channel as a carrier mobility booster. This work explores scaling solutions of FDSOI for sub-20nm nodes, including innovative strain engineering, relying on material, device, process integration and circuit design layout studies. Thanks to mechanical simulations, physical characterizations and experimental integration of strained channels (sSOI, SiGe) and local stressors (nitride, oxide creeping, SiGe source/drain) into FDSOI CMOS transistors, we provide guidelines for technology and physical circuit design. In this PhD, we have in-depth studied the carrier transport in short devices, leading us to propose an original method to extract simultaneously the carrier mobility and the access resistance and to clearly evidence and extract the strain sensitivity of the access resistance, not only in FDSOI but also in strained nanowire transistors. Most of all, we evidence and model the patterning-induced SiGe strain relaxation, which is responsible for electrical Local Layout Effects (LLE) in advanced FDSOI transistors. Taking into account these geometrical effects observed at the nano-scale, we propose design and technology solutions to enhance Static Random Access Memory (SRAM) and digital standard cells performance and especially an original dual active isolation integration. Such a solution is not only stress-friendly but can also extend the powerful back-bias capability, which is a key differentiating feature of FDSOI. Eventually the 3D monolithic integration can also leverage planar Fully-Depleted devices by enabling dynamic back-bias owing to a Design/Technology Co-Optimization

Are low doses of alcohol taken at 2 pm objectively and subjectively more decrement for novices drivers than for more experienced drivers ?

The objective was to evaluate subjective estimation and objective performance of drivers depending on Blood Alcohol Concentration (BAC) and driving experience. Assuming that during monotonous driving performance should be impaired with alcohol at a moment of alertness decrease, the hypothesis was that this impairment would be significant greater for Young Novice Drivers (YND) than for Young Experienced Drivers (YED). 16 YND (18 years, two months of driving) and 15 YED (21 years, 3 years of driving) participated in three simulated driving sessions in which BACs were randomly assigned (0.0, 0.2 and 0.5 g/L). Every session took place between 2 and 4 pm, around one hour after the drink. The circuit represented a typical highway road, the task was to drive during 45 min and to maintain a steady speed (110 Km/h) and a stable position on the lane. After each driving session participants estimated their workload (NASA-TLX questionnaire) and their subjective alertness (Thayer checklist). Driving performance was analysed for steps of 5 min. Globally, placebo session produced higher estimation of alertness, lower estimation of time pressure, physical demand, frustration and effort than BAC sessions. Driving performance was also worse with alcohol. A decrease of alertness and an increase of physical and mental effort were noted with the time-on-task. Thus, evaluation of alertness and effort during monotonous driving task were relatively well correlated with objective performance under the influence of alcohol and with time-on-task. YND had a lower subjective alertness level and estimate to have higher mental and physical workload than YED, their subjective performance and objective driving performance showed an effect of alcohol. YED performance and subjective evaluation are clearly sensitive to alcohol but also to time-on-task (combined effect)

Stratégies d'évitement de collision en intersection

ACAPS 2015 - 16ème Congrès de l'Association des Chercheurs en Activités Physiques et Sportives, Nantes, FRANCE, 26-/10/2015 - 28/10/2015Dans la littérature, certaines études révèlent un effet de la taille des véhicules croisés sur des tâches de jugement et de comportement de conduite des automobilistes à une intersection. Néanmoins, dans ces études, la taille et le type de véhicules croisés (e.g., voiture vs motocyclette) covariaient systématiquement. Cette étude examine séparément l'incidence de la taille et du type de véhicules croisés sur une tâche de jugement et une tâche de franchissement réel d'intersection. Pour cela les voitures et les motocyclettes observées avaient les mêmes dimensions. 14 participants ont réalisé deux expériences dans un simulateur de conduite en réalité virtuelle. Les résultats montrent que les automobilistes utilisaient la taille et type de véhicules croisés pour réaliser les deux tâches

Divided-attention task on driving simulator: comparison among three groups of drivers

Introduction: Driving is a complex and dynamic task that requires performing simultaneously several sub-tasks, as traffic management and vehicle control. Driving involves both automatic and controlled processing depending on situation met and drivers’ experience. Method: Three groups of drivers with different driving experience were submitted to a divided-attention task in order to assess the interference linked to a secondary task on driving behaviour. The main task was a car-following task and the secondary task was a number identification task which could appear on central or peripheral vision. Results and discussion: Results showed that driving performances increase with experience. Indeed, novice drivers, compared to more experienced drivers, took more time to brake and had more difficulties to maintain a stable position in the lane. This task allowed to differentiate driving behaviour depending on experience and could be used in training of novice drivers

Divided attention in young drivers under the influence of alcohol

Aim: The present research evaluates driving impairment linked to two crashes factors, divided attention task and alcohol, and determines whether it is higher for novice drivers than for experienced drivers. Method: Novice and experienced drivers participated in three experimental sessions in which blood alcohol concentrations (BACs) were 0.0 g/L, 0.2 g/L and 0.5 g/L. They performed a divided attention task with a main task of car-following task and an additional task of number parity identification. Driving performance, response time and accuracy on the additional task were measured. Results: ANOVA showed a driving impairment and a decrease in additional task performance from BAC of 0.5g/L, particularly for novice drivers. Indeed, the latter adopt more risky behaviour such as tailgating. In the divided attention task, driving impairment was found for all drivers and impairment on information processing accuracy was highlighted, notably in peripheral vision. Impact of research: The divided attention task used here provides a relevant method for identifying the effects of alcohol on cognitive functions and could be used in psychopharmacological research