Universidad Manuela Beltrán

About: Universidad Manuela Beltrán is a education organization based out in Bogotá, Colombia. It is known for research contribution in the topics: Population & Body mass index. The organization has 690 authors who have published 611 publications receiving 2526 citations.

Análisis de agua no contabilizada en el sistema de abastecimiento urbano del municipio de Facatativá, Colombia

Abstract: espanolContexto: Las perdidas de agua son un obstaculo financiero para empresas prestadoras del servicio de abastecimiento ya que generan perdidas economicas que son trasladadas a los usuarios, elevando de esta manera los costos de suministro del agua. El objetivo de este articulo es presentar un analisis del agua no contabilizada en un sistema de abastecimiento urbano en Colombia. Metodo: Este estudio se realizo a partir de informacion del agua producida (AP) y facturada por el sistema de abastecimiento durante cerca de 16 anos. Se realizo un analisis comparativo con respecto a reportes de agua no contabilizada en sistemas colombianos e internacionales de referencia. Se evaluo tambien la influencia del regimen de precipitacion sobre el indice de agua no contabilizada (IANC). Se realizo finalmente un analisis economico prospectivo mediante modelos ARIMA. Resultados: Se observa un incremento del 5,0% en el IANC por cada 100 000 m3 de AP. Existe un incremento del 2,28% en el IANC por cada incremento de 100 mm en la precipitacion anual. El sistema posee un menor precio en el AP (22,2%) con respecto a sistemas latinoamericanos de referencia. Sin embargo, el sistema posee un mayor precio (33,3%) en relacion con el promedio colombiano. El analisis ARIMA muestra que los efectos del AP en un instante de tiempo determinado se transfieren durante seis meses en el sistema de abastecimiento. Conclusiones: La aplicacion del IANC en sistemas de abastecimiento es una herramienta util para el estudio y desarrollo de programas de control de perdidas de agua. EnglishContext: Water losses are a financial obstacle for supply service providers as they generate economic losses that are passed on to users, thereby raising water supply costs. The objective of this paper is to shows an analysis of non-revenue water in an urban supply system in Colombia. Method: This study was conducted from information of water produced (WP) and billed by the supply system for about 16 years. A comparative analysis was carried out with respect to reports of non-revenue water in Colombian and international reference systems. Rainfall influence on the non-revenue water index (NRWI) was also assessed. A prospective economic analysis was finally carried out using ARIMA models. Results: There is an increase of 5.0% in NRWI per 100 000 m3 of WP. There is an increase of 2.28% in NRWI for each increase of 100 mm in annual rainfall. The system has a lower price on WP (22.2%) in relation with Latin American reference systems. However, the system has a higher price (33.3%) relative to the Colombian average. Analysis ARIMA shows that the effects of AP in an instant of time are transferred during six months in the water supply system. Conclusions: The application of NRWI in supply systems is a useful tool for the study and development of water loss control programs.

Structural and magnetic characterization of the new GdMn1-xFexO3 perovskite material

Abstract: In this paper we presents the synthesis process of the GdMn1-xFexO3 perovskite material by conventional solid state reaction method. Crystalline phase evolution during the synthesis was studied by X-ray Diffraction (XRD) in powder of the materials, observing that the chemical reaction of the precursor oxides was significant above 1000°C. Rietveld refinement of DRX patterns shows a perovskite structure with octahedral distortions (space group Pbnm, # 62) for studied values of x (0, 0.1 and 0.2). The degree of substitution generates an increasing tendency on lattice parameters a and c, while for b is decreasing just as for the volume of the unit cell. The effect of the change in the lattice parameters directly affects the octahedral distortions, ie, with increasing degree of substitution (increased parameter c) octahedra tend to arrange one above the other aligned with the c axis. Magnetization measurements as a function of temperature were performed above room temperature between 300K and 860K with an applied field of 20Oe and below room temperature in Field Cooling (FC) and Zero Field Cooling modes (ZFC) between 4.2K and 300K with an applied field of 200Oe. Magnetic behavior above room temperature is paramagnetic for used values of x, on the other hand at low temperatures (T<30K) magnetic phase transitions associated to the apparition of an antiferromagnetic phase are observed. In addition for x=0.1 the derivative of magnetization shows a peak around 31K, associated to the ferrimagnetic transition for this material. Curie-Weiss fit reveals the antiferromagnetic (ferrimagnetic) behavior of the materials, also shows that the configurations with x=0 and x=0.2 have an effective magnetic moment very similar to the reported value of undoped material, while for x=0.1 a higher value is observed confirming the ferrimagnetic behavior of this configuration.

La interacción social en la ontogénesis de la perspectiva del mundo

Abstract: espanolA principios de este siglo, Donald Davidson adelanto una propuesta que enfatiza el rol de la interaccion como antecedente en la formacion del pensamiento. Diversos autores se han opuesto a su idea porque sostienen que la interaccion social presupone individuos con la capacidad para concebir y coordinar diversos puntos de vista. En este estudio, discuto el alcance de esta critica, mostrando que: a) La interaccion en situaciones de triangulacion puede fluir sin que los participantes tengan pensamientos sobre las perspectivas en juego en la situacion y, b) Ciertos aspectos de la conducta afectiva complementan el bosquejo de la triangulacion. EnglishAt the beginning of this century, Donald Davidson advanced a proposal that emphasizes the role of interaction as an antecedent in the formation of thought. Several authors have opposed his idea because they argue that social interaction presupposes individuals with the ability to conceive and coordinate diverse points of view. In this study, I discuss the scope of this criticism, showing that: a) The interaction in situations of triangulation can flow without participants having thoughts about the perspectives at play in the situation and, b) Certain aspects of affective behavior complement the sketch of triangulation.