Escuelas y Departamentos: Envíos recientes

Mostrando ítems 261-280 de 565

    • Going deeper in the automated identification of Herbarium specimens 

      Carranza-Rojas, José; Goeau, Herve ; Bonnet, Pierre ; Mata-Montero, Erick; Joly, Alexis  (BioMed Central, 2017-08-11)
      Hundreds of herbarium collections have accumulated a valuable heritage and knowledge of plants over several centuries. Recent initiatives started ambitious preservation plans to digitize this information and make it available ...

    • Arquitectura de Alta Disponibilidad en DSpace: Repositorio TEC 

      Alpizar-Chacón, Isaac; Meneses-Guillén, Laura (Instituto Tecnológico de Costa Rica, 2015)
      En la actualidad, el acceso rápido, seguro y eficiente a la información es un aspecto muy importante para todos los usuarios. Un repositorio institucional que no garantiza el acceso a su contenido de forma eficiente y ...

    • Informe Casa Verde 

      Carmona-Jiménez, Marvin; Oconitrillo-Obando, Danny; Pineda-Brenes, María; Solano-Brenes, Carlos; Soto-Vargas, Fabiola; Valverde-Rojas, Daniela (Instituto Tecnológico de Costa Rica, 2016)
      This investigation represents a part of a larger process of diagnosis concerning the enhancement of a Victorian house located in San Jose city, specifically in Barrio Amón. In this work the importance of a correct approach ...

    • Collaborative logical framework: An e-learning assesment tool in .LRN platform 

      Vega-Alvarado, Jose; Francesa-Alfaro, Agustín; Chacón-Rivas, Mario; Garita-Rodríguez, César (LACLO 2016, 2016)
      In the teaching and learning process, one of the most widely used assessments under the constructivist model is to work in groups. This has many advantages, but also weaknesses such as lack of collaboration, poor organization, ...

    • Towards a methodological guide to share knowledge when creating open educational resources 

      Espinoza-Guzmán, Julia; González, Liliana; Forero, Sergio; González, Ana María (LACLO 2016, 2016)
      People claim the right to study and learn what they desire, when and where they want; for this reason it is necessary to offer flexible training methods that provide real opportunities for independent learning. In order ...

    • Cultivo de meristemas, termo y quimioterapia en chayote (Sechium edule Jacq. Sw.) para la erradicación del virus del mosaico del chayote (ChMV) 

      Abdelnour-Esquivel, Ana; Bermudez, L.C.; Rivera, C; Alvarenga-Venutolo, Silvana (2006)
      Recientemente se identificó en Costa Rica una nueva enfermedad viral en chayote, denominada "virus del mosaico del chayote" (ChMV, Chayote mosaic virus). Además de disminuir los rendimientos, esta enfermedad causa reducciones ...

    • Micropropagación de teca (Tectona grandis L.f) 

      Abdelnour-Esquivel, Ana; Muñoz, Anabelle (2005)
      Micropropagation of teak (Tectona grandis L.f.). Teak (Tectona grandis L.f.) is considered valuable due to the quality of its wood. The world level demand for the wood supported the establishment of commercial plantations. ...

    • Estudios preliminares para la crioconservación de especies forestales arbóreas 

      Abdelnour-Esquivel, Ana; Rojas, G; Alfaro, U (2007)
      La crioconservación presenta numerosas ventajas con respecto a otras técnicas que se utilizan rutinariamente para la conservación y almacenamiento de germoplasma. Algunas de estas ventajas son los bajos costos de labor ...

    • Conservación in vitro de chayote (Sechium edule) 

      Alvarenga-Venutolo, Silvana; Abdelnour-Esquivel, Ana; Villalobos-Aránbula, Víctor (2007)
      La técnica de conservación in vitro a mediano plazo fue examinada en chayote. Para ello se determinó la supervivencia de los brotes después de la adición de altas concentraciones de sacarosa (0, 30, 50, 60, 70 y 80 g/l) y ...

    • Evaluation of biodeterioration and the dynamic modulus of elasticity of wood in ten fast-growing tropical species in costa rica exposed to field testing 

      Moya-Roque, Róger (Statny Drevarsky Vyskumny Ustav, 2015)
      In tropical regions, it is possible to produce a large variety of timber species in plantation conditions. However, wood from these trees has low natural durability. Biodeterioration and the dynamic modulus of elasticity ...

    • Engineering of the Stellarator of Costa Rica: SCR-1 

      Piedra, C.; Jiménez, W.; Esquivel, L.; Esquivel, R.; Sánchez, K.; González, J.; Mora-Meléndez, Jaime; Otárola-Zúñiga, Carlos; Vargas-Blanco, Iván (Institute of Physics Publishing, 2015-03)
      This Paper aims at briefly describing the challenge of the design and construction of the Stellarator of Costa Rica 1 (SCR-1) [1]. The SCR-1 is a small modular Stellarator for magnetic confinement of plasma (Ro=0.238 m, ...

    • Effects of thinning on diameter, heartwood, density and drying defects of gmelina arborea 

      Vallejos, Jonathan; Serrano, Rafael; Moya-Roque, Róger (Universidade Federal de Sao Carlos, 2015)
      The effect of three levels thinning intensity in Gmelina arborea plantation on tree diameter, heartwood (diameter and percentage), wood density and drying defects (twist, crook, bow and check) was studied. Wood used for ...

    • Effects of adding nano-clay (montmorillonite) on performance of polyvinyl acetate (PVAc) and urea-formaldehyde (UF) adhesives in Carapa guianensis, a tropical species 

      Rodríguez-Zúñiga, Ana; Vega-Baudrit, José; Alvarez, Vera; Moya-Roque, Róger (Elsevier Ltd, 2015-06)
      The aim of this study was to improve the bond strength resistance of polyvinyl acetate (PVAc) and urea-formaldehyde (UF) adhesives modified with nano-clay (montmorillonite) with a tropical species of wood known to exhibit ...

    • Effects of adding multiwall carbon nanotubes on performance of polyvinyl acetate and urea-formaldehyde adhesives in tropical timber species 

      Rodríguez-Zúñiga, Ana; Vega-Baudrit, José; Moya-Roque, Róger (Hindawi Publishing Corporation, 2015)
      Multiwall carbon nanotubes (MWCNTs) functionalized with hydroxyl groups (MWCNTs-OH) have been incorporated into polyvinyl acetate (PVAc) and urea-formaldehyde (UF) adhesives utilized in tropical wood gluing. The Raman ...

    • Genetic characterization of chayote, Sechium edule (Jacq) Swartz, in Costa Rica by using isozyme markers 

      Abdelnour-Esquivel, Ana; Rocha, Oscar (2007)
      We established protocols for the analysis of genetic diversity in chayote (Sechium edule) by using isozyme markers, thereby determining the level of genetic diversity present in 42 accessions of chayote from Costa Rica. ...

    • Environmental gradients and the evolution of successional habitat specialization: a test case with 14 neotropical forest sites 

      Quesada-Monge, Ruperto; Letcher, Susan; Lasky, Jesse; Chazdon, Robin; Norden, Natalia; Wright, Joseph; Meave, Jorge; Muñoz, Rodrigo; Romero-Pérez, Eunice; Andrade, Ana; Andrade, José Luis; Balvanera, Patricia; Becknell, Justin; Bentos, Tony; Radika, Bhaskar; Bongers, Frans; Boukili, Vanessa; Brancalion, Pedro; César, Ricardo; Clark, Deborah; Clark, David; Craven, Dylan; DeFrancesco, Alexander; Dupuy, Juan; Finegan, Bryan; Pérez-García, Eduardo; González-Jiménez, Eugenio; Hall, Jefferson; Harms, Kyle; Hernández-Stefanoni, José Luis; Hietz, Peter; Kennard, Deborah; Killeen, Timothy; Susan, Laurance; Lebrija-Trejos, Edwin; Lohbeck, Madelon; Martínez-Ramos, Miguel; Massoca, Paulo; Mesquita, Rita; Mora, Francisco; Muscarella, Robert; Paz, Horacio; Pineda-García, Fernando; Powers, Jennifer; Rodríguez, Ricardo; Sandor, Manette; Sanaphre-Villanueva, Lucía; Schüller, Elisabeth; Swenson, Nathan; Tauro, Alejandra; Uriarte, María; Van-Breugel, Michiel; Vargas-Ramírez, Orlando; Viani, Ricardo; Wendt, Amanda; Williamson, Bruce (Blackwell Publishing Ltd, 2015-09)
      Successional gradients are ubiquitous in nature, yet few studies have systematically examined the evolutionary origins of taxa that specialize at different successional stages. Here we quantify successional habitat ...

    • Digital integrated circuit implementation of an identification stage for the detection of illegal hunting and logging 

      Salazar-García, Carlos; Alfaro-Hidalgo, Luis; Carvajal-Delgado, Mauricio; Montero-Aragón, Jordan; Castro-Gonzalez, Reinaldo; Agustín-Rodríguez, Juan; Chacón-Rodríguez, Alfonso; Alvarado-Moya, Pablo (Institute of Electrical and Electronics Engineers Inc., 2015-09)
      Results of the VLSI implementation of an acoustic classification system's identification stage, intended for the detection of gunshots and chainsaws in a protected tropical area, are shown, with the idea of later building ...

    • Design of an IDM-based determinant computing unit for a 130nm low power CMOS ASIC acoustic localization processor 

      Cerdas-Robles, Roberto; Rodríguez, Agustín; Julián, Pedro; Chacón-Rodríguez, Alfonso (Institute of Electrical and Electronics Engineers Inc., 2015-09)
      A determinant computing circuit in floating point format has been designed and tested for use in a CMOS ASIC acoustic localization processor. The Internal Division Method (IDM) was used to implement the operation, employing ...

    • Transport, stability and plasma control studies in the TJ-II stellarator 

      Sánchez, J.; Alegre, D.; Alonso, A.; Alonso, J.; Alvarez, P.; Arévalo, J.; Ascasíbar, E.; Baciero, A.; Baiao, D.; Barcala, J. (Institute of Physics Publishing, 2015-07)
      The main TJ-II results since 2012 are presented in this overview. Impurity confinement is studied showing an isotopic dependence of impurity confinement time, asymmetries in parallel impurity flows in TJ-II ion-root plasmas ...

    • Copper deposition on fabrics by rf plasma sputtering for medical applications 

      Segura, G.; Guzmán, P.; Zúñiga, P.; Chaves, S.; Barrantes, Y.; Navarro, G.; Asenjo, J.; Guadamuz, S.; Vargas, V.; Chaves, J. (Institute of Physics Publishing, 2015-03)
      The present work is about preparation and characterization of RF sputtered Cu films on cotton by the usage of a Magnetron Sputter Source and 99.995% purity Cu target at room temperature. Cotton fabric samples of 1, 2 and ...