A discrete-time system with uncertainty information

This paper considers a discrete-time queueing system with uncertainty information, that is, an arriving customer may opt, with a certain probability, to be served under a Last Come First Served (LCFS) discipline or, with complementary probability, becomes a negative customer. The arrival of a negative customer to the system removes the customer that is currently being served, if any, and has no effect on the system if the server is free. The input stream of the arriving customers is described by means of a Bernoulli process, and the service times are geometrically distributed. Breakdowns can occur, that is, the possibility of a server failure during the service time of a customer is considered, and the customer that was receiving its service in the moment of a failure of the server goes to the first place of the queue. The server has a general life time distribution, and the repair times are ruled by an arbitrary distribution. A thorough study of the model is carried out, and, using a generating function approach, the steady-state distributions of the number of customers in the queue and in the system are obtained.We also give a necessary and sufficient condition for the stability of the system. Characteristics measures of the model are also given. Finally, some numerical examples to illustrate the effect of the parameters on several performances measures of the system are presented.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

ANÁLISIS DE LOS PROGRAMAS SOCIALES DESDE LA PERSPECTIVA DE LOS BENEFICIARIOS DE “GUADALUPE CACHÍ”, IXTLAHUACA, ESTADO DE MÉXICO

Los programas sociales puestos en marcha por el gobierno federal mexicano así como por los gobiernos estatales, han sido una respuesta para combatir el problema, principalmente, de pobreza, dado que, de acuerdo con datos del Consejo Nacional de Evaluación de la Política de Desarrollo Social (CONEVAL), entre 2008 y 2010 la población en pobreza en México tuvo un incremento de 48.8 a 52 millones de personas que viven en tal condición. Al respecto, los gobiernos evalúan los programas en términos del cumplimiento de sus objetivos y metas, es decir, se trata de evaluaciones cuantitativas, en términos de costo beneficio, en las que se mide el número de bienes y/o servicios proveídos y número de beneficiados, los cuales, no terminan de reflejar los cambios positivos o la reducción de pobreza en la población beneficiada con los programas. Sin embargo, ¿se realizan análisis desde la perspectiva de sus beneficiarios, debido a que es una variable fundamental para la evaluación de una política social? Al revisar dos programas, objeto de estudio de esta investigación, la respuesta es que no

Los quilópodos escolopendromorfos del Museo de La Plata

Fil: Coscarón, Sixto. UNLP. FCNyM. Zoología Vertebrado

Algunos progresos y problemas en la Ciencia de la decisión

Sin resume

Ellis Island: Vibration Effects on Historic Buildings Caused by Pile Driving

The seawalls that surround Ellis Island were constructed in the early 1900s and now show varying degrees of deterioration. The approach to the structural repair of the seawalls consisted of installing H-piles and ground anchors for stabilization of vertical and horizontal seawall movements. The H-piles were driven through the retained soils along the seawalls to top of rock. This paper presents ground vibration data collected simultaneously by four seismographs during driving of 40 piles (up to 100 ft depth) at various distances from the historical buildings. A correlation between the recorded PPV values and the distance to pile driving is presented. Also, a specific comparison between the measured attenuations from an instrumented pile with documented driving energy records and those recommended in published literature is presented. It was found that the vibrations induced by pile driving well exceeded the Peak Particle Velocity limits established in the project specifications and those commonly established in the literature. However, damage to the historical buildings was not significant

Literatura y existencia

En el presente artículo se examina el concepto de ficción aplicado a la literatura y al arte en general, dado que la división entre realidad real y realidad ficticia no puede explicar las emociones evocadas por las narrativas y no concluye en ontología satisfactoria de los personajes literarios. Para elaborar una propuesta más explicativa, recurro a la concepción kantiana de la existencia y a las tesis de Meinong y la fenomenología.This paper examines the concept of fiction applied to literature and art in general, since the division between real reality and fictional reality cannot explain the emotions raised by narratives and does not conclude in a satisfactory ontology of literary characters. To develop a more explanatory proposal, I turn to Kant's conception of existence as well as to the views of Meinong and phenomenology