Automated Design of Elevator Systems: Experimenting with Constraint-Based Approaches

System configuration and design is a well-established topic in AI. While many successful applications exists, there are still areas of manufacturing where AI techniques find little or no application. We focus on one such area, namely building and installation of elevator systems, for which we are developing an automated design and configuration tool. The questions that we address in this paper are: (i) What are the best ways to encode some subtasks of elevator design into constraint-based representations? (ii) What are the best tools available to solve the encodings? We contribute an empirical analysis to address these questions in our domain of interest, as well as the complete set of benchmarks to foster further researc

Comparative study of some dynamic properties of liquids and grains in the classroom

Visando entender as diferenças entre as propriedades dinâmicas dos materiais granulares e as propriedades dinâmicas dos líquidos, foram realizados experimentos usando água e grãos de arroz e açúcar. Os experimentos requerem poucos recursos e foram pensados para que possam ser desenvolvidos com facilidade na sala de aula ou num laboratório de ensino. Os resultados mostraram que o fluxo de grãos difere significativamente do fluxo de líquidos.In order to understand the differences in the dynamic properties between granular materials and liquids, experiments using water, rice and sugar grains were performed. The experiments require few material resources and were thought so as to be easily made in a classroom or in a teaching laboratory. The results showed that grain's flow differs significantly from that of liquids.Banco Santande

High homogeneity solenoidal magnet for cesium frequency standard

In Cs frequency standards a zone of highly uniform magnetic flux density, lower in value of 0.1 T, is required. The magnetic homogeneity value is tied to the overall accuracy of the standard and, for an accuracy of 10-14, a design value 1 p.p.m. is required. For this purpose a resistive solenoid 700 mm long with a bore radius of 32.5 mm has been designed and built. This paper reports the design process, the measurements on the manufactured magnet and the shimming strategy used to reach the homogeneity target

Análisis de la estructura genética en poblaciones nativas del Gran Chaco

En este trabajo se presentan algunos análisis sobre la estructura genética de poblaciones nativas del Gran Chaco a partir de la aplicación de dos técnicas analíticas aplicadas a marcadores moleculares de herencia uni y biparental. En general, los resultados muestran que las poblaciones chaqueñas presentan alta diversidad genética y baja diferenciación interpoblacional, en comparación con otras poblaciones sudamericanas, estando presentes un buen número de linajes maternos y paternos, la gran mayoría de ellos compartidos por los distintos grupos de la región. Las distancias genéticas, calculadas a partir de las diferentes variables utilizadas, son bajas y muestran, cada una de ellas, historias diferentes, no coincidiendo con relaciones lingüísticas ni geográficas. Estos resultados podrían estar reflejando patrones culturales anteriores a la colonización europea o bien la ruptura de unidades poblacionales que sobrevino con ésta. Por otra parte, los Ayoreo muestran características genéticas únicas y una diversidad reducida como consecuencia de la acción de algún proceso evolutivo aleatorio, como deriva génica o efecto fundador. Palabras clave: ADN; linajes parentales; distancias genéticas; flujo génico; deriv

Behavioural preference for low levels of UV-B radiation in two neotropical frog species from Costa Rica

Tropical frogs experience damaging effects from exposure to UV-B radiation, and some diurnally active, con- spicuous species exhibit avoidance behaviours to high levels of UV-B. To determine if similar behaviours are present in other diurnal frogs, we experimentally compared UV-B avoidance in two common species of neotropical diurnal frogs – Oophaga pumilio, an aposematic poison frog and Craugastor bransfordii, a cryptic leaf-litter frog – in response to different levels of UV-B. Wild-caught frogs were tested in experimental arenas fitted with filters that permitted two different levels of UV-B (low: 14% vs. high: 84% UV-B). Both species spent significantly more time under the low UV-B filter, suggesting that behavioural preferences for lower levels of UV-B are common to different diurnal species. Furthermore, male O. pumilio significantly preferred lower levels of UV-B, whereas females did not exhibit a preference for lower UV-B, which may suggest differences in UV-B exposure or sensitivity and/or alternative mechanism(s) to avoid UV-B between sexes. Although limited in scope, the findings of our study suggest that UV-B avoidance may be a behavioural adaptation common to all diurnal frogs

Simulation of a molecular QCA wire

Molecular Quantum Dot Cellular Automata (MQCA) are among the most promising emerging technologies for the expected theoretical operating frequencies (THz), the high device densities and the non-cryogenic working temperature. In this work we simulated a molecular QCA wire, based on a molecule synthesized ad-hoc for this technology. The results discussed are obtained by means of iterative steps of ab-initio calculations

Bilateral SMAS rhytidectomy in parotid recurrent pleomorphic adenoma

A case is presented of a young female with parotid recurrent pleomorphic adenoma and skin infiltration treated with subtotal parotidectomy combined with a bilateral superficial muscular aponeurotic system rhytidectomy