Seismic Radiation From Simple Models of Earthquakes

We review some basic features of shear wave generation and energy balance for a 2D anti plane rupture. We first study the energy balance for a flat fault, and for a fault that contains a single localized kink. We determine an exact expression for the partition between strain energy flow released from the elastic medium surrounding the fault, radiated energy flow and energy release rate. This balance depends only on the rupture speed and the residual stress intensity factor. When the fault contains a kink, the energy available for fracture is reduced so that the rupture speed is reduced. When rupture speed changes abruptly, the radiated energy flow also changes abruptly. As rupture propagates across the kink, a shear wave is emitted that has a displacement spectral content that decreases like ω^(-2) at high frequencies. We then use spectral elements to model the propagation of an antiplane crack with a slip-weakening friction law. Since the rupture front in this case has a finite length scale, the wave emitted by the kink is smoothed at very high frequencies but its general behavior is similar to that predicted by the simple sharp crack model. A model of a crack that has several kinks and wanders around a mean rupture directions, shows that kinks reduce the rupture speed along the average rupture direction of the fault. Contrary to flat fault models, a fault with kinks produces high frequency waves that are emitted every time the rupture front turns at a kink. Finally, we discuss the applicability of the present results to a 3D rupture model

Varieties of Skills Profiles in Latin America: A Reassessment of the Hierarchical Model of Capitalism

Research on the politics of skills formation in Latin America is severely underdeveloped. This article offers a novel characterisation of the supply of skills in the region or ‘skills supply profiles’, taking inspiration from the comparative capitalisms literature. We identify four configurations of skills supply profiles – universalising, dual academic-oriented, dual VET-oriented and exclusionary – and analyse their historical dynamics. By doing this, we challenge general assessments of Latin America's skills formation systems as pertaining to one overarching type. This sets the stage for a deeper understanding of the politics of skills in the region and their connection with different development alternatives.Las investigaciones sobre las políticas de formación de habilidades en Latinoamérica se encuentran muy poco desarrolladas. Este artículo ofrece una caracterización novedosa de la oferta de habilidades en la región o ‘perfiles de oferta de habilidades’, inspirándose en la literatura comparativa sobre los capitalismos. Identificamos cuatro configuraciones de perfiles de oferta de habilidades – universalizadores, dual orientado a lo académico, dual orientado a la educación vocacional y capacitación (VET por sus siglas en inglés) y excluyente – y analizamos sus dinámicas históricas. Así, desafiamos las evaluaciones generales de los sistemas de formación de habilidades en América Latina como pertenecientes a un solo tipo. Esto prepara el terreno para un entendimiento más profundo de las políticas de habilidades en la región y su conexión con alternativas diferentes de desarrollo.Pesquisas sobre as políticas de formação profissional são pouco desenvolvidas na América Latina. Inspirado pela literatura sobre capitalismos comparados, este artigo oferece uma caracterização inovadora da oferta de competências na região, ou um ‘perfil de ofertas de competência’. Identificamos quatro configurações dos perfis de oferta de competência – universalizante, acadêmico dual, vocacional dual, e excludente – e analisamos suas dinâmicas históricas. Ao fazê-lo, desafiamos a visão comum de que o sistema de formação de competências na América Latina pertence a um tipo comum e dominante. Essa abordagem permite um entendimento das políticas de competência na região e suas conexões com diferentes alternativas de desenvolvimento

Method for the Calculation of DPA in the Reactor Pressure Vessel of Atucha II

One of the limiting factors of the life of a nuclear power plant (NPP) is the state of the reactor pressure vessel (RPV). Embrittlement is the most important effect affecting RPV aging. The irradiation with neutrons, especially fast neutrons, is the primary cause of this embrittlement. NPP safe operation requires to ensure RPV integrity over its lifetime, threatened by the neutron radiation-induced embrittlement. In this paper, we identify the areas where the RPV neutron radiation is maximum and perform calculations of the displacement-per-atom (DPA) rate in those areas using the MCNP5 code. It was determined that the maximum DPA rate in the RPV wall with fresh fuel element (FE) is 3.76(3) × 10-12 s-1, it takes place in front of FEs BA42 and BL43, and it is symmetrical about the central channel, LG04, and LH03

Evaluation contingente d’aménités paysagères liées à un espace vert urbain. Une application au cas du Parc Balzac de la ville d’Angers

Cet article propose une évaluation contingente des services esthétiques et récréatifs rendus par un parc urbain. Les dispositions à payer d’un échantillon d’usagers d’un parc urbain dans la ville d’Angers (le parc Balzac) ont été révélées sur la base de deux scénarios reflétant des changements d’attributs paysagers. Les attributs retenus correspondent au degré d’ouverture et à l’effort de fleurissement. Lesupport de paiement proposé repose sur une carte de paiement retraçant les augmentations de la taxe d’habitation à prévoir. Nous avons évalué les facteurs qui augmentent la probabilité de donner une disposition à payer positive. Nos résultats montrent que les aménités paysagères recherchées par les visiteurs de deux scénarios du parc Balzac diffèrent. Dans le premier scénario, seul l’usage lié à une activité de loisirs est exprimé, tandis que dans le second, une appréciation esthétique des aménités est également envisagée

Gamification and online consumer decisions: Is the game over?

Consumption can be more than just a necessity; it can become a leisure activity. With the emergence of e-commerce and social media, products and services are just one click away; a trend that is further driven by gamified systems. This research aims to systematically analyze the most relevant academic literature on gamification, to establish if it influences online consumer decisions and, if so, which elements, mechanisms, and theories can explain it. After a thorough search from Web of Science and Scopus databases using SciMAT, 257 papers were analyzed. Twenty-nine (29) of the 36 papers found show empirical evidence that the inclusion of game elements in non-game activities has a significant influence on consumer engagement and online consumer decisions in digital contexts. Moreover, rewards and challenges were identified as the two most used mechanisms, with points, badges, and leaderboards being the most tested gamification elements. The Self- Determination Theory (SDT) and the Technology Acceptance Model (TAM) are the two most common theoretical explanations for why gamification works. Lastly, possible future studies to include thematic, methodological and theoretical agendas were discussed

Frequency‐Dependent Moment Tensors of Induced Microearthquakes

Analysis of 984 induced microearthquakes from The Geysers geothermal reservoir in California reveals that the retrieved moment tensors depend on the frequency band of the inverted waveforms. The observed dependence is more significant for the percentages of the double‐couple, compensated linear vector dipole, and isotropic (ISO) components than for the focal mechanisms. The average root‐mean‐square of the moment tensors obtained in different frequency bands is correlated with spectra of ambient noise. The percentages of double‐couple and ISO components tend to decrease and increase with the upper cutoff frequency (fu), respectively. This suggests that shear rupture radiates energy preferentially in a lower frequency band and tensile rupture in a higher frequency band. Events displaying a strong increase of the ISO with fu are confined within the same depth interval as the injection points. This might be related to the strong thermoelastic effects in the vicinity of injection points that promote opening of small cracks adjacent to the main fractures

Hepatic artery pseudoaneurysm ligation after orthotopic liver transplantation-a report of 7 cases

Pseudoaneurysm (PA) is a rare but life-threatening complication of liver transplantation. The authors present their experience on 7 patients treated by ligation of a post-OLT PA. Hepatic artery ligation or embolization was performed from 10 to 70 days after liver transplantation. Of the seven patients, four survived, one developed a biliary stricture, treated by percutaneous ballon dilatation, two died of a complication not related to treatment, and one died of multiple organ failure. © 1992 by Williams & Wilkins