Training a Convolutional Neural Network for Appearance-Invariant Place Recognition

Place recognition is one of the most challenging problems in computer vision, and has become a key part in mobile robotics and autonomous driving applications for performing loop closure in visual SLAM systems. Moreover, the difficulty of recognizing a revisited location increases with appearance changes caused, for instance, by weather or illumination variations, which hinders the long-term application of such algorithms in real environments. In this paper we present a convolutional neural network (CNN), trained for the first time with the purpose of recognizing revisited locations under severe appearance changes, which maps images to a low dimensional space where Euclidean distances represent place dissimilarity. In order for the network to learn the desired invariances, we train it with triplets of images selected from datasets which present a challenging variability in visual appearance. The triplets are selected in such way that two samples are from the same location and the third one is taken from a different place. We validate our system through extensive experimentation, where we demonstrate better performance than state-of-art algorithms in a number of popular datasets

Diseño de una máquina cilindradora para madera para la elaboración de mangos de utensilios de limpieza

El presente trabajo desarrolla el “Diseño de una Máquina Cilindradora para Madera para la Elaboración de Mangos de Utensilios de Limpieza”, para lo cual, primeramente se seleccionaron las maderas para el proceso de producción, se realizó el diseño de forma definitivo de la máquina, se dimensionó el anillo giratorio y se comprobó su resistencia de diseño, luego se determinó la fuerza de corte en base a la dureza normal a las fibras que tienen estas maderas para calcular los esfuerzos que esta produce tanto en la cuchilla como en el porta cuchilla, se seleccionó la forma y el material de las cuchillas en base al desgaste y al esfuerzo de compresión a que están sometidas. Se calculó la velocidad de corte y de avance, para luego seleccionar el reductor de velocidad. En base a la fuerza de corte y la velocidad angular se determinó la potencia del motor, se escogió la parte más crítica del diseño de la estructura para seleccionar el perfil laminado que soporte la carga a que esta sometida, se seleccionaron los componentes mecánicos para su funcionamiento, finalmente se obtuvo el costo de construcción de la máquina y el precio del producto maquinado

Temperature effect on the electrooxidation of gamma hdroxybutyric acid (GHB) on platinum catalyst through cyclic voltammetry, chronoamperometry, impedance spectroscopy and SERS spectroelectrochemistry

A study of the electro-oxidation of gamma hydroxybutyric acid (GHB) on platinum electrode in acidic media has been investigated by cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy in the temperature range between 5 and 30ºC. The variation of the j-E curves allows the determination of activation energy in a wide interval of potentials where three characteristic oxidation peaks appear. The j-t curves were registered at the more positive potentials corresponding with the A and B peaks. Stationary current intensity measurements allowed the determination of the activation energy in pure kinetic region conditions. Electrochemical impedance spectroscopy made also possible the study of the electrochemical behavior in the same potential region. Temperature dependence of the charge-transfer resistance (Rct) and the rate constant associated with the surface coverage by an adsorbed intermediate (-1=Ro/L) during the GHB electro-oxidation process were evaluated and discussed. In all cases, the values of activation energy, below 30 kJ/mol, suggest that a complex mechanism takes place for the GHB electro-oxidation free of strong interactions with the platinum surface. In situ Surface Enhanced Raman Scattering (SERS) spectroelectrochemistry spectra corresponding to coadsorbed species, including intermediates of reaction, have been analyzed at several potentials

Planeacion Estrategica del area productiva de la ebanisteria Santana de la ciudad de Valledupar

Empresa dedicada a la fabricación de productos en madera al gusto y necesidades del cliente, sobresalen los Muebles Neoclásicos para el hogar, oficina, carpintería para la construcción. Según el número de empleados y el monto de sus activos, se encuentra ubicada dentro del grupo de las pequeñas empresas. Se pretende lograr una Planeación estratégica en el área productiva, con el propósito de mejorar los procesos utilizados para fabricar productos, buscando el mejoramiento continuo y satisfacer sus clientes. Inicialmente se realizó un diagnóstico general; identificando, diagramando operaciones, procedimientos, lo que permitió observar problemas presentes en la fabricación de productos. Con base en este diagnostico se planteó la orientación adecuada en que deben desarrollarse los procesos, mediante un ordenamiento lógico secuencial y la utilización de recursos disponibles; permitiendo procesos de manufacturas mas eficientes que la convertirían en una empresa mas productiva y competitiva. Se determinó el nivel de satisfacción de los clientes; en cuanto a la aplicación de las diferentes técnicas para recolectar información, estableciendo cuantitativamente la percepción, características más relevantes de los usuarios que utilizan los servicios. Se realizó el manual de procedimiento y funciones determinando los cargos necesarios para el desenvolvimiento adecuado de la organización con sus dependencias respectivas.Company dedicated to the production in wood according to the pleasure customer’s necessities. The neoclassical furnitures stand out for the home, office, carpentry for the construction. Depending on the number of employees and active people into the company, it’s located inside the group of the small campanies. It’s sought to achieve a strategic program about productive area, wilth the purpose of improving the processes used to manufacture products, looking for the daily impovement and to satisfy their customers. At the beginning he/she was carried out a general diagnostic, in which identifying, working in operations, procedures what allowed to observe daily problems in the production of products. Taking into account this diagnostic he/she thought about guidance adapted in what the processes should develop, by means of a sequential logical classification and available resources; allowing processes of manufactures will be efficient which would convert it in a productive and competitive company. The level of the customers’ satisfaction was determined; as for the application of the different techniques to gather information, establishing the perception guantitatively, it’s the most outstanding characteristics that customers have when they use the services. He/she did the manual procedure in order to determine the necessary positions for the appropiate development of the organization with its respective dependences, (employees and business)

Genetic Characterization of Jaguars (Panthera onca) in Captivity in Zoological Parks of Colombia

The construction of the pedigree of captive jaguars (Panthera onca) in zoological parks of Colombia was done using the analysis of the Regional Studbook for Jaguars and DNA analysis of 9 microsatellites of 20 Jaguars (n=20). The assignments for paternities and maternities were done with for the program CERVUS and the relationship between animals were established with the KINSHIP program. The analysis of the Studbook was done with SPARKS and PM2000 software generating the following values: genetic diversity for the population (GD=0.7832), potential genetic diversity (GD=0.9113), genic value (GV=0.7846), mean coefficient of inbreeding (F=0.0179), and the Mean KINSHIP (MK) for each individual. The averages of the observed and expected heterozygosity were 0.687 and 0.684 respectively. Nevertheless, a wild jaguar sample of 156 individuals obtained in Colombia substantially showed a higher degree of gene diversity (H = 0.87) than the Colombian captive jaguar population. Thus, the captive jaguar population retained 78 % of the gene diversity of the Colombian wild jaguar population. With this study the pedigree of the captive population of jaguars was built in order to develop an ex situ conservation plan for the species in the Colombian zoological parks

Mobile Voices: Projecting the Voices of Immigrant Workers by Appropriating Mobile Phones for Popular Communication

Mobile Voices, also known as VozMob (www.vozmob.net), is a digital storytelling platform for first generation, low-wage immigrants in Los Angeles to create and publish stories about their communities, directly from cell phones. The project is a partnership between the Annenberg School for Communication at the University of Southern California (USC) and the Institute of Popular Education of Southern California (IDEPSCA), a nonprofit that organizes low-income immigrants in Los Angeles. Founded in 1984, IDEPSCA's programs are focused on education, economic development, health access and reform, popular communication, and worker rights. Currently IDEPSCA runs six day laborer and household worker centers and two day laborer corners where workers look for jobs in a more humane and dignified way while learning about their rights and gaining valuable leadership skills. The Annenberg School for Communication (the research partner) and IDEPSCA (the community partner) came together around the shared goal of designing communication systems and processes that promote media justice and help those without computer access gain greater participation in the digital public sphere. This chapter is a reflection on popular communication, participatory design, andcommunity-based multimedia practice from the Mobile Voices project team. It was collaboratively written by 13 members of the project and includes a project overview and an exploration of themes including the pedagogy of popular communication, participatory technology design, and the dynamic

Macrorremains evidence of anthropogenic recession of Pinus nigra Aiton in Northern Spain

The natural forest landscape of the Duero Basin in Spain¿s Northern Meseta is now reduced to small masses, its demise largely owed to the intense agricultural and stock-raising use made of its lands. The composition of the scant natural masses suggests that formations dominated by broadleaved species once occupied a much greater area. This idea has led to the believe that pine trees have few place within the natural dynamics of this area (Carrión and Fernández, 2009). However, P. pinaster Aiton and P.pinea L. on low-land sandy areas, P. sylvestris L. and P.uncinata Ramond ex DC on mountain high areas have been demonstrated to have played an important role during the Holocene (Franco et al., 2005; Rubiales et al., 2010). The abundant plant remains and moulds of pine wood and cones found on Northern Meseta peat bogs and travertines, now demonstrate its presence on mid-lands during the Quaternary until the last millenni

Farmacología de la nicotina y sus efectos en el sistema nervioso central.

capitulo del libroLos niveles más altos de nicotina en sangre se alcanzan al terminar de fumar un cigarrillo y declinan rápidamente en los siguientes 20 minutos por la amplia distribución en los tejidos corporales. El volumen de distri- bución en humanos es 2.6 veces el peso corporal (Rose et al., 1999). La nicotina es metabolizada por el hígado y se han identificado al menos seis metabolitos primarios, siendo cuantitativamente el más importante la cotinina. Otros metabolitos primarios son la nicotina-N-óxido y el glu- curónido de nicotina. Los metabolitos de cotinina son los siguientes: glu- curónido de cotinina, trans-3-hidroxicotinina y glucurónido trans-3-hi- droxicotininaconacy

Effect of xylanase, cellulase and natural maguey extract on the chemical composition of corn silage and in vitro rumen gas production.

articuloThis study considered the application of two exogenous enzymes, xylanase (XYL) and cellulase (CELL), and maguey extract (ME), (applying 1 ml per kg as fresh matter) and a control (without additive) in four maize silage varieties (San Diego, Cacahuacintle, P-1832 and Victoria), to investigate their effect on the chemical composition (CC), gas production (GP) and in vitro ruminal fermentation. The GP was measured at 0, 3, 6, 9, 12, 24, 36, 48, 72 and 96 hours of incubation. Dry matter disappearance (DMD), organic matter disappearance (OMD), metabolizable energy (ME), and short chain fatty acids (SCFAs) were determined after 96 h of incubation. Data were analyzed using a completely randomized design with a 4×4 factorial arrangement with three replications. The CC showed a significant effect (P<0.05) for varieties with the exception of organic matter (OM), and the inclusion of additives increased the dry matter (DM) and crude protein (CP). A significant effect (P<0.01) was observed for the varieties in the GP parameters and ruminal fermentation. The addition of XYL, CEL and ME promoted dry matter degradation and increased energy availability, with increased in vitro gas production