Prediction of PM10 concentrations using Fuzzy c-Means and ANN

Salamanca has been considered among the most polluted cities in Mexico. The vehicular park, the industry and the emissions produced by agriculture, as well as orography and climatic characteristics have propitiated the increment in pollutant concentration of Particulate Matter less than 10 μg/m3 in diameter (PM10). In this work, a Multilayer Perceptron Neural Network has been used to make the prediction of an hour ahead of pollutant concentration. A database used to train the Neural Network corresponds to historical time series of meteorological variables (wind speed, wind direction, temperature and relative humidity) and air pollutant concentrations of PM10. Before the prediction, Fuzzy c-Means clustering algorithm have been implemented in order to find relationship among pollutant and meteorological variables. These relationship help us to get additional information that will be used for predicting. Our experiments with the proposed system show the importance of this set of meteorological variables on the prediction of PM10 pollutant concentrations and the neural network efficiency. The performance estimation is determined using the Root Mean Square Error (RMSE) and Mean Absolute Error (MAE). The results shown that the information obtained in the clustering step allows a prediction of an hour ahead, with data from past 2 hours

Global Linear Instability at the Dawn of its 4th Decade: A List of Challenges (A Practical Guide on how to Contain the Euphoria and Avoid the Oversell)

Global linear instability theory is concerned with the temporal or spatial development of small-amplitude perturbations superposed upon laminar steady or time-periodic threedimensional flows, which are inhomogeneous in two (and periodic in one) or all three spatial directions.1 The theory addresses flows developing in complex geometries, in which the parallel or weakly nonparallel basic flow approximation invoked by classic linear stability theory does not hold. As such, global linear theory is called to fill the gap in research into stability and transition in flows over or through complex geometries. Historically, global linear instability has been (and still is) concerned with solution of multi-dimensional eigenvalue problems; the maturing of non-modal linear instability ideas in simple parallel flows during the last decade of last century2–4 has given rise to investigation of transient growth scenarios in an ever increasing variety of complex flows. After a brief exposition of the theory, connections are sought with established approaches for structure identification in flows, such as the proper orthogonal decomposition and topology theory in the laminar regime and the open areas for future research, mainly concerning turbulent and three-dimensional flows, are highlighted. Recent results obtained in our group are reported in both the time-stepping and the matrix-forming approaches to global linear theory. In the first context, progress has been made in implementing a Jacobian-Free Newton Krylov method into a standard finite-volume aerodynamic code, such that global linear instability results may now be obtained in compressible flows of aeronautical interest. In the second context a new stable very high-order finite difference method is implemented for the spatial discretization of the operators describing the spatial BiGlobal EVP, PSE-3D and the TriGlobal EVP; combined with sparse matrix treatment, all these problems may now be solved on standard desktop computers.

Reconstructing the Timing and Dispersion Routes of HIV-1 Subtype B Epidemics in The Caribbean and Central America: A Phylogenetic Story.

The Caribbean and Central America are among the regions with highest HIV-1B prevalence worldwide. Despite of this high virus burden, little is known about the timing and the migration patterns of HIV-1B in these regions. Migration is one of the major processes shaping the genetic structure of virus populations. Thus, reconstruction of epidemiological network may contribute to understand HIV-1B evolution and reduce virus prevalence. We have investigated the spatio-temporal dynamics of the HIV-1B epidemic in The Caribbean and Central America using 1,610 HIV-1B partial pol sequences from 13 Caribbean and 5 Central American countries. Timing of HIV-1B introduction and virus evolutionary rates, as well as the spatial genetic structure of the HIV-1B populations and the virus migration patterns were inferred. Results revealed that in The Caribbean and Central America most of the HIV-1B variability was generated since the 80 s. At odds with previous data suggesting that Haiti was the origin of the epidemic in The Caribbean, our reconstruction indicated that the virus could have been disseminated from Puerto Rico and Antigua. These two countries connected two distinguishable migration areas corresponding to the (mainly Spanish-colonized) Easter and (mainly British-colonized) Western islands, which indicates that virus migration patterns are determined by geographical barriers and by the movement of human populations among culturally related countries. Similar factors shaped the migration of HIV-1B in Central America. The HIV-1B population was significantly structured according to the country of origin, and the genetic diversity in each country was associated with the virus prevalence in both regions, which suggests that virus populations evolve mainly through genetic drift. Thus, our work contributes to the understanding of HIV-1B evolution and dispersion pattern in the Americas, and its relationship with the geography of the area and the movements of human populations.

Seguidillas nueuas y curiosas por el A, B, C ; con otras a una Josefa, que pueden aplicarse a otros nombres [Texto impreso]

Hay un ejemplar encuadernado con: Discret rahonament, quiexa formal que fan contra el Micalet de la Seu, la Torre de Espioca, y la Torre de Paterna, sobre la gran visita que éste tingué en lo dia cinc de Deembre [sic] ... per veure y admirar tan magnífica obra y deliciosa vista ... Carlos Quart (que Deu guart) y el señor Don Fernando de Borbó ... : (XVIII/1105).

Coplas por las folias, y otras por el A, B, C. [Texto impreso]

Contiene: Glosas de un amante, que se despide de su dama, hechas por el A, B, C ; Respuesta de la Dama en las otras letras restantes del abecedario

Proceedings of the California Academy of Sciences, 4th series.

4th ser. v. 18 (1929-1930)

Melquisedec, sacerdote de el elyon Uma exegese de Gênesis 14,18-20

Neste estudo, que tem por base Gênesis 14,18-20, se discute a respeito de Melquisedec, o rei de Salém e seu deus el elyon , de quem é sacerdote (v.18). O texto é pós-exílico, sendo uma inserção ao capítulo 14, e reflete a história de Judá no período de sua restauração (séculos 6º a 4º a.C.), numa época em que o sacerdócio de Jerusalém assumiu gradativamente um poder sem precedentes em sua história, de maneira que o sumo-sacerdote acabou por se tornar uma autoridade civil. Melquisedec, que recebe o dízimo de Abrão, é uma imagem que evoca o poder do culto hierosolimitano na sociedade judaíta e seu alegado direito aos dízimos e ofertas oriundos do povo. Mas Melquisedec, usado num texto tardio, pertence a tradições anteriores ao exílio de Judá, segundo as quais o rei também desempenhava papel sacerdotal, como chefe religioso e intendente de Iahweh (Salmo 110). Essa dupla função foi um meio de legitimar as estruturas de poder caracterizadas por uma organização sóciopolítico- econômica que, em aspectos gerais, se ajusta ao conceito de modo de produção tributário. Assim, todo um discurso construído sobre a pessoa do rei e sobre outros aspectos ideológicos, tais quais a teologia de Sião (Salém), serviam de suporte para a manutenção do status quo. E em tal discurso coube o uso do universo simbólico da religião. Neste estudo, aventa-se a hipótese de que el elyon seja um nome composto, no qual subjazem el, que corresponde ao deus supremo do panteão cananeu (o ugarítico ilu), que tem como um de seus atributos o fato de haver gerado céus e terra (o que situa a tradição em concepções cosmogônicas médio-orientais arcaicas); e elyon, o qual parece esconder as características de outro deus, Ba al (Salmo 18, 7-17). Nota-se dessa maneira que o nome do deus de Melquisedec é a combinação sincrética de características de duas grandes divindades do panteão cananeu