Escuelas y Departamentos: Envíos recientes

Mostrando ítems 241-260 de 534

    • 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 ...

    • Constructing a small modular stellarator in Latin America 

      Asenjo, J.; Carvajal-Godínez, Johan; González-Gómez, J.; Soto-Soto, C.; Piedra, C.; Barillas-Mora, Laura; Mora-Meléndez, Jaime; Otárola-Zúñiga, Carlos; Zamora-Picado, Esteban; Vargas-Blanco, Iván (Institute of Physics Publishing, 2015-03)
      This paper aims at briefly describing the design and construction issues of the stellarator of Costa Rica 1 (SCR-1). The SCR-1 is a small modular stellarator for magnetic confinement of plasma developed by the Plasma ...

    • Atmospheric-Pressure Non-thermal Plasma-JET effects on PS and PE surfaces 

      Arrieta, J.; Asenjo, J.; Solís, Y.; Vargas-Blanco, Iván (Institute of Physics Publishing, 2015-03)
      The Atmospheric-Pressure Non-Thermal Plasma (APNTP) has become a topic of a great interest for a wide spectrum of applications in different industry branches, including the surface of treatment processes. In this work we ...

    • Design of a Prototype of Water Purification by Plasma Technology as the Foundation for an Industrial Wastewater Plant. 

      Barillas-Mora, Laura (Institute of Physics Publishing, 2015-03)
      In order to mitigate the contamination of water sources due to the spill of sewage without any kind of treatment, mainly generated by the industrial sector; a prototype of water purification by plasma technology has been ...

    • Are magnetic resonances practical transport controllers in fusion plasmas? the TJ-II experience 

      López-Bruna, D.; Romero, J.; Vargas-Blanco, Iván (Institute of Physics Publishing, 2015-03)
      The TJ-II stellarator is a mid-size Heliac design (high rotational transform, low magnetic shear) that allows for external control of the rotational transform profile. The long experience with locating diverse magnetic ...

    • Application of the X-ray densitometry in the evaluation of the quality and mechanical properties of biomass pellets 

      Tomazello-Filho, Mario; Valaert, Jorre; Tenorio-Monge, Carolina; Moya-Roque, Róger (Elsevier, 2015-04)
      The use of the X-ray technique and the X-ray densitometry to determine pellet particle distribution and to understand the biomass compaction and its effects in pellet properties has been limited. The present work evaluates ...

    • Application of block matrix theory to obtain the inverse transform of the vector-valued DFT 

      Soto-Quiros, Pablo (Hikari Ltd., 2015)
      We study the vector-valued discrete Fourier transform (vector-valued DFT) and its inverse transform, the vector-valued DFT inversion, through its block matrix representation. These transforms are defined for N- periodic ...

    • A top-down design approach for an automated testing framework 

      Méndez-Porras, Abel; Nieto-Hidalgo, Mario; García-Chamizo, Juan-Manuel; Jenkins, Marcelo; Martínez-Porras, Alexander (Springer Verlag, 2015)
      Mobile applications have become popular work tools. Portability and ease of Internet connectivity are characteristics that favor this adoption. However, mobile applications sometimes incorrectly process events associated ...

    • A Parallel Framework with Block Matrices of a Discrete Fourier Transform for Vector-Valued Discrete-Time Signals 

      Soto-Quiros, Pablo (Hindawi Publishing Corporation, 2015)
      This paper presents a parallel implementation of a kind of discrete Fourier transform (DFT): the vector-valued DFT. The vector-valued DFT is a novel tool to analyze the spectra of vector-valued discrete-time signals. This ...

    • Camel: collective-aware message logging 

      Kalé, Laxmikant; Meneses-Rojas, Esteban (Kluwer Academic Publishers, 2015-03)
      The continuous progress in the performance of supercomputers has made possible the understanding of many fundamental problems in science. Simulation, the third scientific pillar, constantly demands more powerful machines ...

    • Energy-Aware Signal Integrity Analysis for High-Speed PCB Links 

      Muller, Sebastián; Reuschel, Torsten; Rimolo-Donadio, Renato; Kwark, Young; Bruns, Heinz-Dietrich; Schuster, Christian (Institute of Electrical and Electronics Engineers Inc., 2015-05)
      This paper proposes a novel approach to evaluate design alternatives for high-speed links on printed circuit boards. The approach combines evaluations of signal integrity and link input power. For a comprehensive analysis, ...

    • Landscape-scale controls on aboveground forest carbon stocks on the Osa Peninsula, Costa Rica 

      Taylor, Philip; Asner, Gregory; Dahlin, Kyla; Anderson, Christopher; Knapp, David; Martin, Roberta; Mascaro, Joseph; Chazdon, Robin; Cole, Rebecca; Wanek, Wolfgang; Hofhansl, Florian; Vilchez-Alvarado, Braulio; Townsend, Alan; Malavassi-Ortíz, Edgar (Public Library of Science, 2015-06)
      Tropical forests store large amounts of carbon in tree biomass, although the environmental controls on forest carbon stocks remain poorly resolved. Emerging airborne remote sensing techniques offer a powerful approach to ...