375 research outputs found
The influence of infragravity waves, wind, and basin resonance on vessel movements and related downtime at the Outer Port of Punta Langosteira, Spain
Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract:] The coupling of low-frequency oscillatory modes of a harbor with horizontal motions of moored ships can amplify the latter, causing operational and safety problems. The objectives of this study were to analyze infragravity waves and their effect on moored ship motions; to validate the Wavelet Transform Analysis (WTA) method for studying port-ship resonance in the Outer Port of Punta Langosteira, Spain; and to study the climatic forcing of downtimes. The excited resonant modes of the basin (102 and 132 s) were determined using a numerical model and high-frequency water level measurements at different points of the harbor. Yaw and sway motions of three bulk carriers were analyzed in the frequency-time domain using WTA. The results showed that the oscillation periods of the studied vessel motions are directly related to the water depth to vessel draft ratio. In addition, when the wind speeds exceeds 20 km/h, the ship moves away from the fenders, which lead to a lengthening of these periods. Based on our findings, yaw may induce oscillations of the same period in sway. Additionally, operational thresholds were proposed based on outer and inner waves data that will lead to optimize ship stays, avoiding downtimes, and to advance the safety of loading and unloading operations.This research was funded by the Spanish Ministry of Economy, Industry, and Competitiveness, R&D National Plan (BIA2017-86738-R), the Spanish Ministry of Science and Innovation, Retos Call (PID2020-112794RB-I00 / AEI/10.13039/501100011033) and the FPI predoctoral grant from the Spanish Ministry of Science, Innovation, and Universities
(PRE2018-083777). Funding for open access charge: Universidade da Coru˜na/CISUG. The authors are grateful to the Port Authority of A Coru˜na (Spain), the crew of reference vessels for their
kind collaboration on board, Aqu´atica for providing the pressure gauge data, and IHCantabria for the MSP model
Babel
Babel, proyecto finalista de la Tercera Edición del Concurso Internacional de Jardines Urbanos,
BilbaoJardín 2011, se presenta como un espacio de interacción social, que forma parte de una
red de actuaciones puntuales de carácter efímero, en diversas plazas de la ciudad de Bilbao.
La actuación trata de activar y estimular el espacio urbano consolidado, mediante la disposición
de una instalación habitable, que genere una nueva identidad del espacio público, fomentando
la implicación de la ciudadanía en el proceso creativo, la concienciación sobre la reutilización
de materiales, así como el respeto y cuidado del nuevo espacio público que se ofrece.
Babel es también un proceso de investigación con una metodología que se desarrolla
fundamentalmente en cuatro ámbitos diferenciados, que son la formación de un equipo
multidisciplinar, la creación de una plataforma informativa virtual, el desarrollo de prototipos y la
participación ciudadana. Dichos estados se retroalimentan entre ellos, beneficiando a las
personas que intervienen y consecuentemente a la propuesta.
La propuesta parte desde el proyecto flexible como carácter fundamental de su naturaleza,
capaz de adaptarse a las condiciones de contorno y al contexto de su futuro emplazamiento.
La realidad descontextualizada de la bases del concurso permite la ideación inusual del
proyecto, lo que implica la interpretación del mismo como parte de un ciclo, un proceso
material abierto en el que la ciudadanía asume un papel creativo y de producción, obteniendo
un resultado susceptible de ser transformado en su vida útil.
Entendemos que la puesta en carga del proceso creativo previa construcción física y espacial,
conlleva el enriquecimiento de las personas que en él intervienen y la mejora sustancial de la
propuesta. Se ha conseguido por tanto una mayor entendimiento, una mayor aceptación y
valoración del espacio público, por parte de la ciudadanía, activa, participativa.Babel, finalist Project in the third edition of the International Competition of Urban Gardens,
BilbaoJardín 2011, is presented as a space for social interaction, belonging to a network of
specific actions with an ephemeral character, which are located in different squares in the city of
Bilbao.
The purpose of this action is to activate and stimulate the consolidated urban space, through
the disposition of an habitable installation, which generates a new identity to the public space,
promoting citizens implication in the creative process, awareness of the need of recycling
materials, as well as respect and care of the new public space which is offered.
Babel is also a process of investigation with a methodology which is developed basically in four
areas: multidisciplinary teams formation, creation of a virtual informative platform, development
of prototypes and the citizen participation. These areas feed one another, which benefits people
who take part in it, and consequently, the proposal.
The proposal starts from a flexible project as an essential part of its nature, which is able to
adapt itself to the environmental conditions and to the context of its future sitting. The
decontextualised reality of the regulations of the completion allows the unusual design of the
project, which implies its interpretation as a part of a cycle, an open material process in which
the citizens assume a creative and productive role, obtaining a result which is susceptible of
being transformed through its useful life.
We understand that developing the creative process previous a physical and spatial
construction implies the enrichment of the people who take part in it and a substantial
improvement of the proposal. Therefore, it has been reached a better understanding,
acceptance and valuation of the public space by active and participative citizens
Genome sizes and karyotypes in the razor clams "Ensis arcuatus" (Jeffreys, 1865) and "E. siliqua" (Linnaeus, 1758)
[Abstract] The razor clams Ensis arcuatus and E. siliqua show a diploid DNA content of 3.85 ± 0.049 pg and 4.00 ± 0.050 pg, respectively. Both have a diploid chromosome number of 38 although their karyotypes show remarkable differences. The karyotype of E. arcuatus consists of 4 metacentric, 1 metacentric-submetacentric, 7 submetacentric and 7 telocentric chromosome pairs, whereas that of E. siliqua possesses 3 metacentric, 7 submetacentric and 9 telocentric pairs. In situ hybridization using an 18S-5.8S-28S rDNA probe located this ribosomal locus on one chromosome pair for both species. Results demonstrate that large differences exist between them, probably caused by chromosome rearrangements along evolution of these two species, and increase the number of studies on bivalve cytogenetics.Xunta de Galicia; PGIDT99 MAR1030
Ensayos de hormigones fabricados con polvo de corcho
[ES] Este trabajo de investigación tiene por objeto conocer algunas propiedades físicas y mecánicas de un hormigón elaborado en laboratorio, adicionándole diversas proporciones de polvo de corcho. Las propiedades del material resultante, si bien carecen de la resistencia mecánica que caracteriza al hormigón, parecen interesantes para su uso en ciertas aplicaciones de la ingeniería agronómica tales como en la fabricación de piezas para solados de parques infantiles y jardines, o en los cubículos de ciertas construcciones ganaderas, extremos que es preciso analizar y comprobar
Mechanical behaviour of grapevine wood affected by Xylotrechus arvicola
[EN] The cerambycid insect Xylotrechus arvicola is considered a pest that affects the wood of the grapevine (Vitis vinifera) in the major wine areas of the Iberian Peninsula. The larva of this insect perforates the grapevine wood, resulting in structural and biomechanical failure of the vine plants. Vine samples from wood damaged by X. arvicola larvae were picked up from different vineyards and grape varieties. Compressive and flexural tests were performed in order to assess the mechanical behaviour of the wood samples. Total length of the cracks in wood samples (TLCWS) that appeared on the surface of the grapevine wood samples after the mechanical tests was measured. Compressive strength (CS) and flexural strength (FS) decreased with the increase of the cross-sectional area (CSA) of both branches and trunks, regardless of damage condition or water content. Moreover, the resistance was lower in damaged wood. In addition, this was verified through the linear regression coefficients of the interaction CS x CSA and FS x CSA. TLCWS in branches and trunks of damaged samples was greater that in undamaged samples. Also, TLCWS within the same damage condition and part of the plant was higher in dry samples than in fresh samples. The damaged wood would show a higher vulnerability to common mechanical stress suffered by the grapevines in the field including heavy winds, fruit overweight or harvesting machines shaking (when mechanically collected). Larvae of this insect altered the mechanical behaviour of the trunk and branches of grapevine wood. The mechanical strength of wood was more negatively affected when the CSA of the branches and trunks increased. Longer TLCWS was found in affected wood
Síndrome de kartagener: bronquiectasias como manifestación broncopulmonar, reporte de caso y revisión de la literatura
Kartagener syndrome, an autosomal recessive genetic disorder with an estimated low incidence of 1: 15,000 cases, is part of primary ciliary dyskinesia, a rare genetic disease caused mainly by defects in genes related to the structure of the cilia, the incidence of dyskinecia as a cause of bronchiectasis in adults varies between 0.9% and 10.3%.1,2 Glandular secretion, impaired ciliary function, and immune system dysfunction can predispose to infection and therefore the development of bronchiectasis. Patients with Kartagener syndrome have multiple episodes of respiratory tract infection and exacerbation of bronchiectasis due to poor mucociliary clearance and accumulation of secretions in the lower airways. 3,4 The main clinical manifestation of bronchiectasis is chronic productive cough and thick crackles in the lungs. 4,5 Chest tomography is the ideal imaging study for its detection. 4 Treatment of most causes of bronchiectasis includes antibiotics, oxygen therapy, anti-inflammatories, mucolytic drugs, chest and respiratory physiotherapy. 6 We present the clinical case of a patient with kartagener syndrome with a family history with the same syndrome, positive smoking, bronchiectasis as a bronchopulmonary manifestation, and recurrent respiratory tract infection.El síndrome de Kartagener, trastorno genético autosómico recesivo con una baja incidencia calculada de 1:15000 casos, forma parte de las discinecias ciliares primarias, enfermedad genética poco común causada principalmente por defectos en genes relacionados con la estructura de los cilios, la incidencia de las discinecias como causa de bronquiectasias en adultos varía entre 0,9% y 10,3%. 1,2 La secreción glandular, la función ciliar alterda y la disfunción del sistema inmunitario pueden predisponer a la infección y por tanto al desarrollo de bronquiectasias. Los pacientes con síndrome de Kartagener tienen múltiples episodios de infección del tracto respiratorio y exacerbación de las bronquiectasias debido al aclaramiento mucociliar deficiente y acumulación de secreciones en las vías aéreas inferiores. 3,4 La principal manifestación clínica de las bronquiectasias es la tos productiva crónica y crepitantes gruesos en los pulmones. 4,5La tomografía de tórax es el estudio de imagen ideal para su detección. 4 El tratamiento de la mayoría de las causas de bronquiectasias incluyen antibióticos, oxigenoterapia, antiinflamatorios, farmacos mucoliticos, fisioterapia torácica y respiratoria. 6 Se presenta el caso clínico de un paciente con síndrome de kartagener con antecedente de familiar con el mismo síndrome, tabaquismo positivo, bronquiectasias como manifestación broncopulmonar e infección de vías respiratorias recurrentes
Quality Assessment of Mixed and Ceramic Recycled Aggregates from Construction and Demolition Wastes in the Concrete Manufacture According to the Spanish Standard
[EN] Construction and demolition waste (CDW) constitutes an increasingly significant
problem in society due to the volume generated, rendering sustainable management and
disposal problematic. The aim of this study is to identify a possible reuse option in the
concrete manufacturing for recycled aggregates with a significant ceramic content: mixed
recycled aggregates (MixRA) and ceramic recycled aggregates (CerRA). In order to do so,
several tests are conducted in accordance with the Spanish Code on Structural Concrete
(EHE-08) to determine the composition in weight and physic-mechanical characteristics
(particle size distributions, fine content, sand equivalent, density, water absorption,
flakiness index, and resistance to fragmentation) of the samples for the partial inclusion of
the recycled aggregates in concrete mixes. The results of these tests clearly support the
hypothesis that this type of material may be suitable for such partial replacements if simple
pretreatment is carried out. Furthermore, this measure of reuse is in line with European,
national, and regional policies on sustainable development, and presents a solution to the
environmental problem caused by the generation of CDW
Influence of the use of External Carbon Fiber Reinforcement on the Flexural Behavior of Prismatic Concrete Test Specimens. An Application for Repairing of Deteriorated Agricultural Structures
This manuscript reports a study of the capacity of polymer composites to increase flexural
strength in concrete. The polymer composites reinforced with carbon fiber and bonded with epoxy
adhesive were used in prismatic test specimens of mass concrete corresponding to two different
morphologies. The aim was to simulate the restoration of deteriorating concrete agricultural structures
in order to explore the viability of this alternative against replacing them. An increase was found in
the strength of the elements tested, with a higher strength being observed in those test specimens
presenting a modified geometry.NOThis research was funded by SPANISH MINISTER OF ECONOMY AND COMPETITIVENESS, grant number BIA2017-83526RThe authors acknowledge the technical support and material used for experiments donated by Sika Grou
Mechanical behaviour of grapevine wood affected by Xylotrechus arvicola
The cerambycid insect Xylotrechus arvicola is considered a pest that affects the wood of the grapevine (Vitis vinifera) in the major wine areas of the Iberian Peninsula. The larva of this insect perforates the grapevine wood, resulting in structural and biomechanical failure of the vine plants. Vine samples from wood damaged by Xylotrechus arvicola larvae were picked up from different vineyards and grape varieties. Compressive and flexural tests were performed in order to assess the mechanical behaviour of the wood samples. Total length of the cracks in wood samples (TLCWS) that appeared on the surface of the grapevine wood samples after the mechanical tests was measured. Compressive strength (CS) and flexural strength (FS) decreased with the increase of the cross-sectional area (CSA) of both branches and trunks, regardless of damage condition or water content. Moreover, the resistance was lower in damaged wood. In addition, this was verified through the linear regression coefficients of the interaction CS x CSA and FS x CSA. TLCWS in branches and trunks of damaged samples was greater that in undamaged samples. Also, TLCWS within the same damage condition and part of the plant was higher in dry samples than in fresh samples. The damaged wood would show a higher vulnerability to common mechanical stress suffered by the grapevines in the field including heavy winds, fruit overweight or harvesting machines shaking (when mechanically collected). Larvae of this insect altered the mechanical behaviour of the trunk and branches of grapevine wood. The mechanical strength of wood was more negatively affected when the CSA of the branches and trunks increased. Longer TLCWS was found in affected wood.of an emerging grape pest, Xylotrechus arvicola (Coleoptera: Cerambycidae
Pre-Saturation Technique of the Recycled Aggregates: Solution to the Water Absorption Drawback in the Recycled Concrete Manufacture
The replacement of natural aggregates by recycled aggregates in the concrete
manufacturing has been spreading worldwide as a recycling method to counteract the large
amount of construction and demolition waste. Although legislation in this field is still not
well developed, many investigations demonstrate the possibilities of success of this trend
given that concrete with satisfactory mechanical and durability properties could be
achieved. However, recycled aggregates present a low quality compared to natural
aggregates, the water absorption being their main drawback. When used untreated in
concrete mix, the recycled aggregate absorb part of the water initially calculated for the
cement hydration, which will adversely affect some characteristics of the recycled
concrete. This article seeks to demonstrate that the technique of pre-saturation is able to
solve the aforementioned problem. In order to do so, the water absorption of the aggregates
was tested to determine the necessary period of soaking to bring the recycled aggregates
into a state of suitable humidity for their incorporation into the mixture. Moreover, several
concrete mixes were made with different replacement percentages of natural aggregate and various periods of pre-saturation. The consistency and compressive strength of the concrete
mixes were tested to verify the feasibility of the proposed techS
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