Revistas Universidad del Bío-Bío
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Repensando a Relação entre Lugar e Memória: Reflexão sobre a memória urbana
No full textRepensar el lugar respecto a su relación con la memoria, supone una oportunidad de indagar cómo ha sido entendido el lugar en la construcción de la memoria, a fin de reflexionar acerca de los procesos de significación que van más allá de una mera referencia geográfica, bajo el principio de la llamada espacialidad vivida. Para ello se propone hacer una revisión de tres autores David Harvey, Paul Ricoeur y Pierre Nora, esto supone una oportunidad para ampliar el discurso mediante tres visiones desde diferentes disciplinas, bajo el principio de generar una comprensión complementaria respecto al lugar y su relación con la construcción de la memoria en general y, en específico de la memoria urbana, a fin mostrar las posibilidades que tiene el lugar en la conformación de ésta, al revalorar la al lugar como un elemento primario en la construcción de la memoria, la cual adquiere múltiples posibilidades cuando se trata de la memoria urbana, pues la ciudad es y será una ventana abierta para construir y reconstruir la memoria colectiva más allá de monumentalidad.Repensar o lugar com respeito à sua relação com a memória, é uma oportunidade para investigar como o lugar foi compreendido na construção da memória, a fim de refletir sobre os processos de significado que vão além de uma mera referência geográfica, sob o princípio da chamada espacialidade vivida. Para isso, propomos uma revisão de três autores David Harvey, Paul Ricoeur e Pierre Nora, esta é uma oportunidade de ampliar o discurso através de três visões de diferentes disciplinas, sob o princípio de gerar uma compreensão complementar do lugar e sua relação com a construção da memória em geral e especificamente da memória urbana, a fim de mostrar as possibilidades que o lugar tem na conformação disto, revalorizando o lugar como elemento primário na construção da memória, que adquire múltiplas possibilidades quando se trata de memória urbana, porque a cidade é e será uma janela aberta para construir e reconstruir a memória coletiva além da monumentalidade.Rethinking the place with respect to its relationship with memory, is an opportunity to investigate how the place has been understood in the construction of memory, in order to reflect on the processes of meaning that go beyond a mere geographical reference, under the principle of the so-called lived spatiality. For this purpose, it is proposed to review three authors: David Harvey, Paul Ricoeur and Pierre Nora. This is an opportunity to broaden the discourse through three visions from different disciplines, under the principle of generating a complementary understanding of place and its relationship with the construction of memory in general and, specifically, of urban memory, in order to show the possibilities that the place has in the conformation of this, by revaluing the place as a primary element in the construction of memory, which acquires multiple possibilities when it comes to urban memory, because the city is and will be an open window to build and rebuild the collective memory beyond monumentality
Emociones ante la crisis de los misiles en Cuba. El discurso de J.F. Kennedy, 1962
Get PDFEl presente artículo analiza las emociones de miedo e ira contenidas en el discurso del presidente estadounidense John F. Kennedy que pronuncia en televisión el día 23 de octubre de 1962 debido a la amenaza que significa la instalación de bases soviéticas con misiles nucleares en la isla de Cuba, en lo que se conoce como la Crisis de los Misiles. Se sostiene que, dado el peligro inminente de una amenaza nuclear, el miedo y la ira son emociones centrales en este discurso puesto que se articulan como elementos significativos que ayudan en la legitimación de una posible acción bélica radicalmente violenta que podría incluir armamento nuclear. Por medio del análisis historiográfico y del discurso, se establecen las palabras que denotan o connotan seguridades e inseguridades en el discurso mencionado y, con ello, se evidencian las emociones. Primero, se constituyen los elementos teóricos y metodológicos a trabajar. Segundo, se caracteriza el contexto de la época. Finalmente, se realiza el análisis del discurso que muestra las emociones contenidas.This article analyzes certain emotions, such as fear and anger, presented in the speech given by the American President John F. Kennedy, on October 23rd 1962 due to the threat caused by the installation of Soviet bases in Cuba. This is known as the Missile Crisis. In this speech, emotions such as fear and anger can be provoked, due to the exposure to risk situations which may result in possible future nuclear attacks. After analyzing the speech and historical documents, it can be inferred that there exist some words that show certain and insecurities during it. That is when emotions are established. First, some theoretical and methodological framework will be stated. Second, the period and era will be contextualized. Finally, there will be some analysis about the speech and the emotions involved. 
Evaluation of wood-based coating performance for ultraviolet roller and conventional air-atomization processes
Get PDFIn this study, the effects of two different coating processes on the surface coating performance of wood-based panels were investigated. The samples were prepared using an ultraviolet (UV) roller coater and conventional air-atomized systems. Adhesion strength, surface coating hardness, and layer thickness were selected as the coating performance parameters. These coating performance parameters were analyzed using an analysis of variance (ANOVA), Grubb’s test, and probability plot. Adhesion strength, surface coating hardness, and layer thickness were measured using the pull-off test, pendulum hardness, and ultrasonic layer thickness, respectively. According to the ANOVA results, the coating process type was the most significan
Comparative analysis of the physical and mechanical properties of kraft paper and watercolor paper
Get PDFIn order to study the feasibility of kraft paper as watercolor paper, the wetting properties, mechanical properties and friction properties of kraft paper and watercolor paper were compared before and after aging. Aging test was carried out on kraft paper and watercolor paper by aging chamber, the wetting properties of distilled water and three watercolor solutions before and after aging of kraft paper and watercolor paper were compared, tensile tear test of paper on tensile testing machine, the fracture changes of paper were analyzed by scanning electron microscope, the friction tester performs the paper friction test. The results show that both kinds of paper are amorphous, watercolor paper was showed hydrophobicity before and after aging, contact angle was maintained at about 119,09° ± 5° in four different solutions, unaged kraft paper exhibited hydrophilicity, the aged kraft paper showed hydrophobicity with a contact angle of 92,52° ± 1°，the aged kraft paper shows better performance in both tensile and tearing aspects and tensile strength is 20 MPa higher than watercolor paper, surface roughness of kraft paper is higher than watercolor paper. The experiment is helpful for the market to consider whether the cheaper kraft paper replaces the more expensive watercolor paper in some aspects and provides some scientific reference value for the future research
Theoretical model for further development of intumescent substances to remediate smoldering in wood fiber insulation panels
Get PDFWood fiber insulation boards, as many other wooden materials, are susceptible to smolder. This type of slow and flameless thermal degradation has three upmost important drawbacks. First, smoldering can develop unseen until damages are noticed; second, it does not need any external heat to keep progressing, thus behaving as a self-sustaining process; third, it may shift into flaming combustion. Although wooden insulation materials are very competitive as insulators, its use is not permitted in several countries beyond mid-rise buildings due to smoldering hazard. As measuring of physical parameters is difficult and expensive at high temperatures, the objective of this investigation was to develop a theoretical model that comprises most relevant physical phenomena in order to serve as a supportive tool for further development of fire-retardant substances. The constructed model presents the novelty that it can simulate the self-sustaining smoldering without needing any external radiation heat, but only the self-heating generated by its own exothermic reactions. The model was built based on a program of experimental testing that included thermo-gravimetric analyses and differential-scanning calorimetry, being able to predict particle degradation at different heating rates and oxygen concentrations with errors of about 7,5 %. The adequacy of the model was also compared at the structural scale against a non-standard cone calorimeter test with terminal switching off heat radiation to emulate self-sustaining smoldering, which was used as model validation showing fits of about 23 % in consideration of mass loss, mass-loss rate and temperature profile. A comprehensive sensitivity analysis comprising 60 distinct parameters permitted to thoroughly assess the influence of each model input parameter, which is being presented as a ranking from the most to the less influencing parameters that prevent or foster self-sustaining smoldering. Several unexpected conclusions raised, positioning species’ densities, capacities and reaction activation energies as the most important parameters. To the best knowledge of the authors, this is the first model that can simulate the self-sustaining smoldering of wooden insulation materials, so it is expected to contribute on further development of fire retardant compounds for wooden products.  
Compressive strength parallel to grain of earlywood and latewood of yellow pine
Get PDFThe compressive strength parallel to grain of earlywood and latewood from the yellow pine sapwood and heartwood areas was examined in the study. The structure of the basic structural elements of wood - tracheids, which conduct water and/or perform the mechanical function - was also characterized. The compressive strength parallel to grain of latewood in the sapwood area was found to be twice as high as the compressive strength parallel to grain of earlywood. The compressive strength parallel to grain of latewood in the heartwood area, on the other hand, was found to be 2,5 times higher than the compressive strength parallel to grain of earlywood. This was due to the density of particular areas of wood and the dimensions of structural elements - tracheids. In the sapwood area, the density of latewood was ca. twice as high as the density of earlywood. Similar relationships were found for heartwood. The thickness of latewood tracheids was found to be 1,5 times greater than the thickness of earlywood tracheids. These relationships were observed in sapwood and heartwood. The diameter of earlywood tracheids in radial direction was twice as large as the diameter of latewood tracheids. These relationships were observed in yellow pine sapwood and heartwood
Automatic identification of charcoal origin based on deep learning
Get PDFThe differentiation between the charcoal produced from (Eucalyptus) plantations and native forests is essential to control, commercialization, and supervision of its production in Brazil. The main contribution of this study is to identify the charcoal origin using macroscopic images and Deep Learning Algorithm. We applied a Convolutional Neural Network (CNN) using VGG-16 architecture, with preprocessing based on contrast enhancement and data augmentation with rotation over the training set images. on the performance of the CNN with fine-tuning using 360 macroscopic charcoal images from the plantation and native forests. The results pointed out that our method provides new perspectives to identify the charcoal origin, achieving results upper 95 % of mean accuracy to classify charcoal from native forests for all compared preprocessing strategies
Some surface characterıstıcs of orıental beech wood ımpregnated wıth some fıre-retardants and coated wıth polyurea/polyurethane hybrıd and epoxy resıns
Get PDFThis study was made to determine surface characteristics such as colour, gloss, and surface hardness changes of Oriental beech (Fagus orientalis). The wood specimens were firstly impregnated with some fire-retardants (FRs) and primed with epoxy resin (EPR) and then coated with polyurethane/polyurea hybrid resin (PUU). Oriental beech was impregnated with 3 % aqueous solution of boric acid (BA), borax (BX), boric acid and borax mixture (1:1), and ammonium sulphate (AS). While Sikafloor®-156 was used for epoxy coating (EPR), Sikalastic®-851 R was used for polyurethane/polyurea hybrid coating (PUU). According to our results, all treatment groups gave negative lightness stability values after accelerated weathering. The colour stability of epoxy resin coated Oriental beech was higher than that of polyurethane/polyurea hybrid resin coated Oriental beech. Except for boric acid impregnated and polyurethane/polyurea hybrid resin coated Oriental beech, all fire-retardants treatment before polyurethane/polyurea hybrid resin and epoxy resin coatings decreased the gloss losses of Oriental beech after accelerated weathering. Fire-retardants impregnation before epoxy resin and polyurethane/polyurea hybrid resin coatings improved the surface hardness values of Oriental beech after accelerated weathering
Editorial
Get PDFARQUITECTURA MÁS ALLÁ DE LA SUSTENTABILIDADEs un hecho que la pandemia Covid 19 ha impactado no solo nuestras vidas, sino también la disciplina de la arquitectura, que ha alzado la mirada hacia la salud y bienestar de las personas que habitan espacios arquitectónicos. La verdad es que el bienestar de los ocupantes ha sido materia de interés disciplinar desde ya hace varios años, pero se ha visto enfatizado aún más con los requerimientos de higienización y calidad ambiental de los espacios, derivados de la pandemia. Hoy, esperamos que la arquitectura sustentable no solo apunte a mitigar los impactos negativos que las edificaciones generan sobre el medio ambiente sino también entregue espacios saludables, confortables, centrados en los habitantes. De esta manera, la agenda de sustentabilidad en la arquitectura, usualmente orientada hacia aspectos ambientales como energía cero, eficiencia hídrica o economía circular, comienza a abarcar la dimensión social con mucha más fuerza. Quizás esta tendencia surge en parte como reacción a los edificios de alto desempeño que mantienen la lógica de la arquitectura internacional del siglo XX –un estilo arquitectónico para todos los climas– donde una envolvente con materiales altamente tecnologizados, sistemas de climatización e iluminación sofisticados y eficientes permiten eficientes desempeños ambientales en distintos contextos. Actualmente, en distintas partes del mundo, se aboga por una arquitectura más “humanizada”
Reflections of Le Corbusier on the work of Álvaro Siza
Get PDFThis research article navigates through the different common lines seen between the life and work of two of the most relevant architects of the 20th century: Le Corbusier and Álvaro Siza. Though belonging to different times, they both constitute indisputable examples of the architecture of their times, where several aspects in common appear, inviting us to think about the unconscious influence of the Swiss master on the work of the Portuguese architect over the years.Este artigo de pesquisa propõe um percurso através das diversas linhas comuns encontradas na vida e obra de dois dos arquitetos mais relevantes do século XX: Le Corbusier e Álvaro Siza. Embora tenham vivido em épocas diferentes, ambos são referentes indiscutíveis da arquitetura de seu tempo. Entre eles podem-se contatar inúmeros pontos em comum, os quais nos convidam a suspeitar de uma influência inconsciente do professor suíço no arquiteto português ao longo dos anos.El presente artículo de investigación plantea un recorrido por las diferentes líneas comunes advertidas entre la vida y la obra de dos de los arquitectos más relevantes del siglo XX: Le Corbusier y Álvaro Siza. Aunque pertenecientes a diferentes épocas, ambos constituyen indiscutidos referentes de la arquitectura de su tiempo en los que asoman numerosos aspectos en común que invitan a pensar en una influencia inconsciente del maestro suizo sobre el trabajo que el portugués desarrolló a lo largo de los años