Compresión de Audio Basada en Codificación Subbanda

An eight channels subband audio codec is implemented for signals with 44.1 KHz and 16 bits per sample using Matlab. To achieve perfect reconstruction, a two channels QMF filter bank with cutoff frequency ω=π/2 is designed, based on an equiriple filter of 99 order. Seven stages of this bank are used to split the input into eight signals with sample rates from 2.76 to 11 KHz, which are coded from 1 to 16 bits depending on the band energy. To evaluate performance for three tracks in terms of similarity of input and output signals, a Mean Opinion Score (MOS) experiment with fifteen subjects was performed. The Euclidean Distance between spectrums was also measured. Results showed a fair similitude for two tracks and excellent for one. Compression factors above 96% were achieved.Keywords: subband coding, mean opinion score MOS, QMF filter banks, audio compressio

Análisis del conocimiento de las herramientas de propiedad intelectual por las empresas en Santa Marta

El presente artículo de investigación, presenta los resultados de la medición del conocimiento de las herramientas de protección para las creaciones intelectuales que utilizan diversas empresas en Santa Marta. Fueron consultadas 19 empresas del sector manufacturero, clasificadas en cuatro grupos según activos, que fueron seleccionadas usando muestreo por conveniencia. Los resultados muestran que las empresas destinan recursos para la investigación, aunque en algunas no hay responsable de investigación y desarrollo; las definiciones de propiedad industrial y derecho de autor son de dominio en la mayoría. Hay diversos grados de conocimiento en los títulos de propiedad intelectual, de los cuales los secretos empresariales y las marcas, tiene mayor reconocimiento seguido de las patentes de invención y los diseños industriales, que tiene un nivel medio y las patentes de modelo de utilidad, denominaciones de origen e indicaciones de procedencia que tienen bajo nivel de reconocimiento. La superintendencia de industria y comercio, y la dirección nacional de derechos de autor no son reconocidas por las empresas como entidades del sistema de propiedad intelectual colombiano. El estado colombiano percibido como un actor pasivo en su papel de promotor del uso y aprovechamiento de la propiedad intelectual en el país. Por último, por cada ítem analizado se proponen medidas para corregir y mejorar la apropiación de la materia en las empresas de Santa Marta.Abstract: This research paper presents the results of measurement of knowledge of the tools of protection for intellectual creations using various companies in Santa Marta. Were consulted 19 manufacturing companies, classified into four groups based assets, we selected using convenience sampling. The results show that companies allocate resources for research, although some no responsibility for research and development; the definitions of industrial property and copyright are most domain. There are varying degrees of knowledge on intellectual property titles, of which trade secrets and trademarks, has greater recognition followed by patents and industrial designs, which have an average level and utility model patents, designations of origin and indications of origin that have low recognition. The Superintendency of Industry and Commerce, and the National Directorate of Copyright is not recognized by companies as entities Colombian intellectual property system. The Colombian state perceived as a passive actor in his role as promoter of use and exploitation of intellectual property in the country. Finally, for each item discussed measures to correct and improve the appropriation of matter in Santa Marta companies are proposed

Adquisición de señales ambientales para un sistema de alerta temprana

This article presents a prototype of environmental signal acquisition system as part of an early warning system, in order to manage possible floods in the Manzanares river basin in Santa Marta, Colombia. The system aims to monitor the soil moisture, rainfall and water level of the site under study, as well as register, store and send these variables in real time through the cellular network. The prototype responds satisfactorily in different test conditions, acquiring the environmental signals and sending remotely to the server. With the performed configuration, sensors show stable output and good response to sudden changes in soil moisture and water level. The acquisition device represents an achievement in terms of low cost hardware integration for risk mitigation due to [email protected]

Control predictivo-cooperativo para operar una red de bombas centrífugas en un sistema serial de poliductos

Los sistemas de ductos brindan una conexión entre puertos, campos petrolíferos, refinerías y mercados de [email protected]