Manejo sostenible de los residuos generados en las actividades de construcción y demolición de edificaciones

pdfLos objetivos que se plantean van dirigidos a reducir los impactos ambientales negativos ocasionados por la construcción y demolición de las edificaciones, igual de lo que se podrían y deberían hacer en cuanto a minimizar y mitigar dichos impactos. Para esto, se desarrolló un plan de manejo de residuos de la construcción y demolición en el lugar de la edificación y su destino final, con aplicación al estudio de un caso: Edificios Multifamiliares del Fondo de Cesantía del Magisterio Ecuatoriano - FCME, en cuanto a la identificación, caracterización, cuantificación y evaluación de los residuos sólidos, mal llamado escombros generados por la construcción de edificacione

Comportamiento organizacional y estructuras corporativas rentables de las microempresas con liderazgo y trabajo en equipo.

El objetivo es identificar el comportamiento organizacional de las microempresas para desarrollar estructuras corporativas rentables, a partir de conceptos claros y entendibles sobre liderazgo, presentando casos prácticos y reales que permitan comprender mejor las definiciones y mediante casos analíticos poder identificar las estructuras que pueden ser usadas en una microempresa. Para el desarrollo de este trabajo se aplicarán los métodos, bibliográfico, deductivo, descriptivo, analítico, sintético y comparativo.The objective is to identify the organizational behavior of microenterprises to develop profitable corporate structures, based on clear and understandable concepts on leadership, presenting practical and real cases that allow a better understanding of the definitions and through analytical cases to identify the structures that can be used in a micro-business. For the development of this work, the bibliographic, deductive, descriptive, analytical, synthetic and comparative methods will be applied

Estudio comparativo del borde dorsal del cuello de equinos miniatura

The aim of this article was to study of dorsal neck in miniature horses. We studied a total of 125 breed’s miniature: miniature horses, Falabella, Shetland Pony, Miniature donkey and tiny (45 castrated males and 80 females), aged 2-20years, undergoing glow-intensity exercise at different conditions management and feeding. Morphologicconsideringbody conditionwas performedfollowing the protocol fat adiposityfor evaluating thedorsaledge of the neckdescribed forhorses.The weightwas calculatedusingthe equation systemdescribedfor miniaturehorses. Descriptive statisticsofmorphometric measurementsof the neckwasperformedand the analysisof variance (ANOVA). Morphologicalstudyshowed rating1.-44% (55/125), score 2.-32% (40/125), score 3.-19% (24/125), 4.-5% rating (6/ 125). The neck perimeter was presented as follows: Minihorse: DS: 4.194, average:43.4, variance:17.24, Minishetland:DS:13.33, average:55.1, variance:174.21, Falabella: DS: 8.52, average:54.48, variance:71.24, MiniatureDonkey: DS: 8.79, Half: 47, variance:75.72, donkey tiny: DS: 25.69, average: 55.68, variance: 25.17. In conclusion, describe the deformation of the dorsal border of the neck miniature horses, with higher prevalence miniature donkeys and dwarves in the other miniature breeds studied, which is possibly associated with body condition specifically obesity and decreased athletic activity that develop these equine.Se plantea como objetivo un estudio comparativo del borde dorsal del cuello en equinos miniatura. Fueron estudiados un total de 125equinos miniatura de razas Falabella, MiniatureHorse, Pony Shetland, burro miniatura y enano (45 machos castrados y 80hembras), con edades comprendidas entre 2-20 años, sometidos a ejercicio de baja intensidad y diferentes condiciones de manejo y alimentación. Se realizó un estudio morfológico considerando la condición corporal, siguiendo el protocolo de adiposidad para la evaluación del borde dorsal del cuello descrito para equinos. El peso fue calculado empleando el sistema de ecuaciones KER descrito para caballos miniatura. Se realizó una estadística descriptiva a las medidas morfométricas del cuello y posteriormente se realizó un análisis de varianza (ANOVA). El estudio morfológico en evidenció una Puntuación 1.- 44% (55/125), Puntuación 2.- 32% (40/125), Puntuación 3.- 19% (24/125), Puntuación 4.- 5% (6/125). El perímetro cervical por raza se presentó de la siguiente manera: Minihorse: DS: 4.194, Media: 43.4, Varianza:17.24, Minishetland: DS: 13.33, Media: 55.1,Varianza: 174.21, Falabella: DS: 8.52, Media: 54.48, Varianza: 71.24, Burro Miniatura: DS: 8.79, Media: 47, Varianza: 75.72, Burro enano: DS: 25.69, Media: 55.68, Varianza: 25.17. En conclusión describimos la deformación del borde dorsal del cuello en equinos miniatura, con mayor prevalencia en burros miniatura y enanos, que en las otras razas miniatura estudiadas, la cual está asociada posiblemente a la condición corporal específicamente a la obesidad y a la disminuida actividad atlética que desarrollan estos équidos

Caracterización mecánica de recubrimientos de aluminio-silicio depositados por CVD-FBR sobre el acero inoxidable AISI 316 y oxidado en vapor de agua

(Eng) Aluminum-Silicon Al-Si coating deposited at 540 °C on the austenitic stainless s teel AISI 316 by chemical vapor deposition in fluidized bed reactor (FBR-CVD), afterwards samples were thermally treated at 750 °C under argon for 2 hours. The coated samples were oxidized in water vapor loop at 750 °C, which showed a decrease in the corrosion rate at high temperatures in respect with the oxidized uncoated substrate (more than 100 times). Microhardness and nanoindentation studies were performed in order to assess the benefits of the Al-Si coating by CVD-FBR, finding an increase in the coating hardness with respect to the substrate. Additionally Scanning Electron Microscopy (SEM) was carried out to characterize micro-structural chang - es of the oxidized samples. Cross-section samples were subjected to Atomic Force Microscopy (AFM) fo - cusing on the thickness of coating (topographical changes, roughness gradient and possible formed phases). Results of AFM verified a correlation between hardness and voltages profiles found during scanning.(Spa) El recubrimiento de Aluminio-Silicio fue depositado a 540 °C sobre el acero austenítico AISI 316 por deposición química de vapor en lecho fluidizado (CVD-FBR), para luego ser tratado a 750 °C en argón por 2 horas. Las muestras de estudio fueron oxidadas en un loop de vapor a 750 °C, los cuales presentaron una disminución en la velocidad de corrosión a altas temperaturas con respecto a las muestras no recubiertas (más de 100 veces). Estudios de Microdureza y Nanoindentación fueron realizados con el fin de evaluar los beneficios del recubrimiento de Al-Si por CVD-FBR, encontrando un incremento en la dureza del recubrimiento con respecto al sustrato. Adicionalmente, Microscopía Electrónica de Barrido (SEM) fue llevada a cabo para caracterizar los cambios en la microestructura de las muestras oxidadas. La sección transversal de las muestras fue sometida a Microscopía de Fuerza Atómica (AFM), enfocándose en el espesor del recubrimiento (cambios topográficos, gradiente de rugosidad y posibles fases formadas). Los resultados AFM verificaron una correlación entre la dureza y los perfiles de voltaje encontrados durante los barridos

Effects of thinning intensity on radial growth patterns and temperature sensitivity in Pinus canariensis afforestations on Tenerife Island, Spain

The final publication is available at Springer via http://dx.doi.org/10.1007/s13595-011-0125-8The suitability of thinning to prevent forest growth decline from global warming has been 25 scarcely tested in the Macaronesian Canary pine (Pinus canariensis Sweet ex Spreng.). We used tree-ring series from dominant, codominant, and overtopped trees to study the 27 effects of thinning intensity on basal area increments (BAI) and climate sensitivity on windward 28 (wet) and leeward (dry) slopes on Tenerife, Canary Islands. Three replicated blocks of control, 29 light thinning, and heavy thinning stands were set on each slope in 1988, and cores were 30 extracted in 2007. Heavy thinning induced growth release and increased BAI, mainly on dominant and 32 codominant trees, whereas light thinning effects were negligible; their impacts were more intense 33 on windward. Temperature sensitivity was hardly affected by thinning on leeward, where climate 34 control was stronger. On windward, thinning enhanced the influence of summer temperatures. 35 Upper crown classes were overall more sensitive, but overtopped trees responded better in 36 summer. Thinning intensity and aspect greatly influence growth on Canary pine afforestations, but 38 individual responses are highly dependent on crown classes. In addition, thinning may be less 39 effective to modify growth conditions on leeward slopes, at least if it is not intense.We thank A. González, S. Lamas, P. Manso, I. Outeda, B. Rodríguez-Morales and A. Soliño for laboratory assistance, N. Muñoz for statistical advice, and two anonymous reviewers for providing valuable comments on the manuscript. The staff of Corona Forestal Natural Park of Tenerife facilitated site accession. We gratefully acknowledge the effort 380 of staff and technicians that designed and executed the thinning experiment in 1988. V. Rozas benefited by a visiting fellowship to the University of La Laguna, funded by Consellería de Innovación e Industria, Xunta de Galicia, and research contracts by INIA-Xunta de Galicia and 383 CSIC. This research was partially funded by Consellería de Innovación e Industria, Xunta de Galicia (PGIDIT06PXIB502262PR) and INIA, Spanish Ministry of Science and Innovation (RTA2006-00117)

Nosotros, vosotros, ellos: relatos de viajeros judíos del siglo XV a la luz del concepto de alteridad

Travel literature could be considered as the nexus of numerous types of texts within the narrative genre. Nevertheless, the information it offers from historical, geographical or sociological, among others, points of view, converts it into a register from which are concealed the own experiences of travelers in their journeys. In this sense, these ones are specially relevant in identity studies in which it is possible to observe the alterity that the authors show in their writings describing, in a constant way, their perception of the places they visited but also different communities, Jewish and non-Jewish, they find. In these pages it is offered a study about the impressions of 15th century Medieval authors in their voyages.La literatura de viajes podría considerarse el nexo de multitud de tipos de textos dentro del genero de la narrativa. Sin embargo, los datos que ofrece desde el punto de vista histórico, geográfico o sociológico, entre otros, hacen de ella un registro del que subyacen además las experiencias propias de los viajeros en sus travesías. De este modo, resultan especialmente destacadas en estudios de identidad en los que observar la alteridad que muestran los autores en sus escritos en los que describen, de manera constante, su percepción de los lugares que visitan pero también las diferentes comunidades, judías y no judías, con las que se encuentran. En estas paginas se ofrece un estudio acerca de las impresiones de autores medievales del siglo XV en sus viajes

El confort y la seguridad en la vivienda social urbana

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Unit Commitment and Generation Dispatch of a Hydropower Plant in a Competitive Electricity Market

Abstract. This paper presents a model to solve the short-term scheduling problem of a hydropower plant in a deregulated system, based on dynamic programming techniques. The objective of this model is to maximize the revenue obtained by selling energy in a competitive electricity market. The time horizon of the model is divided into hourly periods and ranges from one day to one week. The proposed model determines both the unit commitment and the power to be generated in each hour of the time horizon. The power is considered as a nonlinear function of the water discharge and the reservoir volume; the dependence of the units and plant operating limits on the available gross head has been taken into account; and the water discharged through the spillway has been also allowed for in the model. This approach has been applied to a practical case study, the results of which are analyzed in detail. Key words. Hydropower plant, competitive electricity market, short-term scheduling, head dependence, dynamic programming. Interest of the work his paper considers a price-taker hydropower plant that sells its energy in the day-ahead electricity market, i.e., it does not have influence on the hourly market clearing prices. Bidding strategies considering the effect of the plant production on the market clearing procedure are therefore outside the scope of this paper. One of the main difficulties faced by most hydro scheduling models lies in the nonlinear relationship existing among the power generated, the water discharge and the net head. For short-term studies the head dependence is usually neglected, especially in the case of large reservoirs, as their variation throughout the planning time horizon is barely significant. Nevertheless, in Spain, and in many other countries all over the world, there are many hydro plants associated to a reservoir the regulating capacity of which is weekly, daily or even smaller, as it is the more and more frequent case of small to medium head hydropower plants with a limited and environmentally respectful flooded area. In these cases, the head dependence should be considered in order to obtain realistic results. , among others. It should be noted that, depending on the market environment, the plant regulating capacity and whether the power generation system is hydro-or thermal-based, the focus of the models may vary slightly but essentially, most approaches proposed in the literature are applicable in a broad range of cases. In linear programming based models, the hydro generation characteristic is usually reduced to a single unit performance curve approximated either through a piecewise linear curve In nonlinear programming based models it is important to avoid the nonconcavity, or nonconvexity (depending on the considered approach), of the objective function since it may result in multiple local optima. In addition, the management of the unit start-ups and shut-downs by means of binary variables leads in these cases to nonlinear mixed integer programming problems Due to the inherent complexity of the problem, it is usual to find in the literature approaches that decompose it into a unit commitment subproblem (UCS) to determine the unit status (on/off), and a generation dispatch subproblem (GDS) to determine the optimal power generation. In Dynamic programming is probably one of the first methods used to solve hydro scheduling problems, whatever the time horizon or the predominant source of energy in the system. Recent studie

Resistência à corrosão em um ambiente salino aço carbono revestido com alumínio por aspersão térmica e pintura poli aspártica

The corrosion resistance was assessed in saline environment on a 1020 steel coated with aluminum by arc thermal spraying and then a polyaspartic paint was applied. It was observed that this system has a protection in these environments, reducing the corrosion rate, compared to a bilayer paint system, which consisted of zinc-rich paint layer and polyaspartic coating. Coating characterization was performed by SEM to analyze their behavior with respect to the substrate and paint to meet variations in properties such as adhesion, homogeneity and topography. It was observed that the samples coated with aluminum by thermal spraying showed good corrosion resistance in salt spray the specimens that were not coated, just were protected by the bilayer coating system, even the paint without thermal spraying performed well and that did not fail during the time stipulated in test for salt spray.Se evaluó la resistencia a la corrosión en ambiente salino del acero 1020 recubierto con aluminio por medio de rociado térmico por arco eléctrico y después se aplicó una pintura poliaspártica. Se observó que este sistema presenta una protección en estos ambientes, reduciendo la velocidad de corrosión, en comparación con un sistema de pintura bicapa, el cual consistía en una capa rica en zinc y otra capa de pintura poliaspártica. Se realizó la caracterización del recubrimiento por medio de Microscopia Electrónica de Barrido (MEB) para analizar su comportamiento con respecto al sustrato y a la pintura para conocer variaciones en propiedades como adherencia, topografía y homogeneidad. Se observó que las probetas recubiertas con aluminio por rociado térmico presentan una mayor resistencia a la corrosión en cámara salina que las probetas que no fueron recubiertas y solo estaban protegidas por el sistema bicapa de pintura, aunque la pintura sin rociado térmico tuvo un buen desempeño ya que no falló durante el tiempo estipulado para en ensayo en cámara de niebla salina.A resistência à corrosão em solução salina ambiente 1020 aço revestido com alumínio por aspersão térmica de arco foi avaliado e, em seguida, foi aplicada uma tinta poli aspártico. Observou-se que este sistema tem uma protecção nestes ambientes, reduzindo a taxa de corrosão, em comparação com um sistema de pintura de duas camadas, que consistia de um fardo rico em zinco, e outra camada de tinta poliaspártica. Revestimento caracterização foi realizada por SEM para analisar o seu comportamento em relação ao substrato e a tinta para satisfazer as variações nas propriedades de adesão, tais como, a uniformidade e a topografia. Observou-se que as amostras revestidas com alumínio por aspersão térmica apresentam uma maior resistência à corrosão em sal pulverizar as amostras que não foram revestidas sozinho foram protegidas pelo sistema de revestimento de duas camadas, embora bem a tinta sem pulverização térmica e realizada ele não falhou durante o tempo estipulado para ser testado em névoa salina. &nbsp