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Análisis comparativo de costos entre sistemas combinado y dual con capacidad Mínima de disipación de energía en zona de amenaza sísmica baja en el país
No full textDesde hace varios años en Colombia se evidencia un incremento significativo en el costo del metro cuadrado de los predios; ubicándose la ciudad de Barranquilla en el octavo puesto con mayor valorización predial entre el año 2010 y 2020, con un aumento de 74.4% (Hernández, Llanes, & Téllez, 2021). Por otro lado, se ha observado un alza en los precios de los insumos del sector construcción a través del Índice de Costos de la Construcción de Edificaciones (ICODEC), por lo cual, se prevé una posible reducción en la capacidad económica de los inversionistas. Ambas problemáticas enfatizan la necesidad de construir cada vez más alto, implementando sistemas estructurales más económicos. En consecuencia, esta investigación plantea un análisis comparativo de costos entre un par de edificios de 40 pisos con dos sistemas estructurales: combinado y dual. Para esto, inicialmente se caracterizó la zona de amenaza sísmica y de viento considerando las disposiciones del Título A y B de la NSR-10. Posteriormente, se construyeron los modelos matemáticos utilizando ETABS; esto considerando materiales lineales y efectos P delta. Luego, se ejecutó el análisis y diseño estructural teniendo en cuenta las disposiciones de la ASCE 7-22 y el ACI 318-19. Después, se realizó un despiece detallado de cada sistema estructural y con ello, se extrajeron las cantidades de obra para realizar el análisis de costos de concreto y acero. Como resultado se obtuvo que el Sistema Combinado es un 23% más económico respecto al Sistema Dual.For several years in Colombia there has been a significant increase in the cost of the square meter of land, placing the city of Barranquilla in the eighth position with the highest property valuation between 2010 and 2020, with an increase of 74.4% (Hernández, LLanes, & Téllez, 2021). On the other hand, a rise in the prices of materials for the construction sector has been observed through the Building Construction Cost Index (ICODEC), and therefore, a possible reduction in the economic capacity of investors is foreseen. Both problems emphasize the need to build higher and higher, implementing more economical structural systems. Consequently, this research proposes a comparative cost analysis between a pair of 40-story buildings with two structural systems: combined and dual. For this, the seismic and wind hazard zone was initially characterized considering the provisions of Title A and B of NSR-10. Subsequently, the mathematical models were built using ETABS; this considering linear materials and P-delta effects. Then, the structural analysis and design was executed considering the provisions of ASCE 7-22 and ACI 318-19. Afterwards, a careful detailing view of each structural system was made and with it, the material schedules were extracted to perform the cost analysis of concrete and steel. As a result, the Combined System is 23% more economical than the Dual SystemLista de Tablas y Figuras11--Tablas11—Figuras 16--Introducción 20-- Planteamiento del Problema 21-- Justificación 24--Objetivos 26-- Objetivo General 26-- Objetivos Específicos 26-- Marco Bibliográfico 27-- Marco Normativo 27-- NSR-10: Reglamento Colombiano de Construcción Sismorresistente 27-- ACI 318-19: Building Code Requirements for Structutal Concrete 32-- ASCE 7-22: Minimum Design Loads and Associated Criteria for Buildings and Other Structures 36-- Marco Conceptual 49-- Sistema Combinado 49--Sistema Dual 49-- Carga Viva 49--Carga Viva de Cubierta 50-- Base 50 --Cortante Basal 50-- Edificio 50 --Concreto Reforzado 51-- Viga de Acople 51—Deformabilidad 51--Diafragma 51-- Deriva de Piso 52-- Efectos del Viento en Edificios Altos 52 --Estado del Arte 52-- Origen de los Edificios de Altura 52-- Primeros Avances Tecnológicos: Concreto Reforzado 53-- Sistema Combinado y Dual en Edificios Altos 54-- Edificios Altos en el Mundo 56-- Edificios Altos en Latinoamérica 58-- Edificios Altos en Colombia 59 --Metodología 62-- Fase 1: Investigación del Marco Conceptual y Estado del Arte 62-- Fase 2: Caracterización de la Amenaza Eólica 62—Fase 3: Caracterización de la Amenaza Sísmica 66 Fase 5: Construcción de Modelos Matemáticos 81-- Fase 6: Análisis Eólico 91-- Procedimiento 91-- Resultados Globales 103-- Fase 7: Análisis Sísmico 113—Procedimiento 113-- Resultados Globales118-- Fase 8: Diseño EstructuraL 127-- Sistema Combinado 127 --Sistema Dual 150-- Fase 9: Verificación de Diseño Estructural 167-- Viga 167-- Viga de Acople 177-- Muro 180-- Columna 200-- Fase 10: Despiece de Elementos Estructurales 206-- Fase 11: Cantidades de Obra 206-- Concreto 206 --Acero 207—Fase 12: Costos de Material 211--Análisis de Resultados 213-- Análisis de Cantidades y Costos de Concreto 213-- Análisis de Cantidades y Costos de Acero 215-- Análisis de Costos por Nivel y Metro Cuadrado 216-- Análisis de Costos Totales 217-- Conclusiones 218-- Referencias 220--Ingeniero(a) CivilPregrad
Red de centralidades, articuladora del urbanismo social en el hábitat popular de la periferia conurbada de Barranquilla y Soledad, 2023
No full textLista de Figuras y Tablas 10--Introducción 15-- Justificación 16-- Planteamiento del problema 18-- Hipótesis 19 --Objetivos 21-- Objetivo general 21 --Objetivos específicos 21-- Diseño metodológico 23-- Marco teórico 26-- Equipamiento colectivo en el hábitat popular26-- El equipamiento como productor de capital social 27-- Impacto del equipamiento en el proceso de la segregación 28-- Identidad social en la periferia conurbada 29-- Participación ciudadana en la producción del espacio 31-- La psicología de la apropiación 33-- Construcción social en la periferia 34-- La centralidad como parte de la red 36-- La centralidad en la periferia 37-- Nuevas centralidades como oportunidad 38 --Ejes de articulación como estrategia de intervención 39-- Estado del arte 41--Diagnóstico 47-- Contexto histórico: Proceso de conurbación entre Barranquilla y Soledad 47-- Barrios en la periferia conurbada de Barranquilla y Soledad 56-- Área de intervención 59-- Aspectos socioeconómicos 60-- Aspectos urbanos 62--Itinerario de reconocimiento 76-- Estudio de casos 69-- Caso Barcelona: Áreas de nueva centralidad 70-- Caso Quito: Fortalecimiento de centralidades urbanas de Quito 71 --Caso Medellín: Programa de parques, bibliotecas y equipamientos educativos para dignificar los barrios 72-- Centralidades en la periferia conurbada de Barranquilla y Soledad 73 --Centralidad los Robles 76-- Centralidad Ciudadela 80 --Centralidad el Parque 84 --Centralidad Simón Bolívar 88-- Propuesta: Modelo de intervención para el fortalecimiento del sistema de centralidades en la periferia conurbada 94-- Modelo de intervención: Movilidad sustentable 96-- Modelo de intervención: Regeneración urbana 98 --Propuestas: Centralidad los Robles 100-- Propuestas: Centralidad Ciudadela 103--Propuestas: Centralidad el Parque 110-- Propuestas: Centralidad Simón Bolívar 115-- Conclusiones 120-- Referencias 124-- Artículos científicos virtuales ¡Error! Marcador no definido. Libros 125-- Tesis 126-- Normas, decretos e informes gubernamentales 127-- Referencias 128—Anexos 129--Arquitecto(a)Pregrad
An analysis of management by competencies in grocery retail distributors
No full textCompetency-based management models are models through which the specific competencies for each job position are evaluated. This contemplates the development of additional competencies necessary for the personal and professional growth of employees. Therefore, in this research, a model is analyzed from theoretical and methodological bases, with the aim of knowing the skills of retail store managers so that they can keep their businesses at the forefront of this sector. The inductive scientific method was used with a methodology of two steps. The first stage consisted of carrying out a systematic study of the literature from the critical point of view of hermeneutics. In the second step, the core competency analysis approach is applied to generate a list of ten core competencies. It is concluded at the end of the study that in the retail economic sector, which consists mainly of various products such as food and groceries in general, many of the managers of this type of business currently focus their attention on customer orientation and decision-making through assertive communication. However, it was revealed that this technique can be enhanced by expanding the digital and computer skills of these managers, which will allow them to position their micro-businesses in the first place soon since in this sector they do not use the latest technologies because they do not master digital and computer skills
La Libreta militar como requisito obligatorio para el empleo formal en Colombia
No full textColombia surge como Estado de Derecho y automáticamente el servicio militar obligatorio. Este mismo ha replicado la dinámica internacional de reclutar a jóvenes para las filas del ejército nacional, legalmente conocidas "fuerzas públicas de hoy", donde se les obliga a cumplir con ciertos deberes, pero asimismo pasan por alto derechos fundamentales y el debido proceso. Sobre las libretas militares poco se investiga y asimismo se escudriñe, lo que, si es cierto, es que definir esta situación militar puede tornarse tedioso en su proceso al punto de perder oportunidades de estabilidad como lo son el estar empleado. Este trabajo de investigación se basa en identificar las falencias que presenta el proceso de registro militar para obtener la libreta y como se ha convertido durante años en una barrera para que muchos jóvenes no puedan acceder a un empleo, cómo funciona el Ejército Nacional en estos casos particulares, cuantos jóvenes han perdido la oportunidad de un trabajo formal, y como esto no lo enmarca de manera expresa la constitución política, lo que ha llevado a que este tema sea poco controversial y apoyadoColombia emerges as a rule of law and mandatory military service is automatically imposed. This has replicated the international dynamic of recruiting young people into the ranks of the national army, legally known as "today's public forces", where they are required to comply with certain duties, but they also undergo high fundamental rights and due process. Little is investigated or scrutinized about military notebooks, which, if true, is that defining this military situation can become tedious in its process to the point of losing opportunities for stability such as being employed. This research work is based on identifying the shortcomings that the military registration process presents to obtain the booklet and how it has become for years a barrier for many young people not to be able to access employment, how the National Army works in these cases. individuals, how many young people have lost the opportunity for a formal job, and how this is not expressly framed by the political constitution, which has led to this issue being little controversial and supported Little is investigated and scrutinized about military notebooks, the truth is that defining this military situation can become tedious in its process to the point of losing opportunities for stability as an employee. This research work is based on identifying the shortcomings of the military ID process and how for many years it has become a barrier for many young people not to be able to access employment, how the National Army works in these particular cases, how many young people have lost the opportunity for a formal job, and since this is not expressly framed in the political constitution, which has led to this issue being little controversial and supported.Tablas y Figuras 9-- Introduccion 10-- Capitulo I Planteamiento Del Problema 14--
Formulación Del Problema 17-- Hipotesis 18-- Antecedentes 19-- Objetivos 24-- Objetivo General 24-- Objetivos Específicos 24-- Delimitación 25-- Delimitación Temporal 25-- Delimitación Espacial 25-- Delimitación Científica 25-- Líneas 26--Sublineas 26--
Capitulo II Justificacion 27-- Marco Legal 31-- Marco Teórica 33--Metodologia 37-- Capitulo III Analisis y Resultados 39--Normatividad Vigente sobre el Reclutamiento en Latinoamerica 39-- Servicio Militar Obligatorio a Nivel Constitucional 46-- Constitución Politica de Cundinamarca 46-- Control y Regulacion de la Carta Politica de Rafael Nuñez 47-- Establecido en la Ley 1 de 1945 48-- Establecido en la Ley 37 De 1978 50-- Establecidos en la Ley 131 de 1985 50-- Establecido en la Constitución Politica De 1991 51-- Estableicdo en la Ley 1861 de 2017 52-- Servicio Obligatorio como Deber Constitucional 55-- Servicio Militar Solidario según La Constitución 56--Regulación Actual 61-- Ley 1861 62-- Procedimiento de Inscripción e Incorporación 63-- Serivicio Militar en Tiempo 65-- En Relación al Servicio Militar 66-- Exención y Aplazamiento 68--Normas Comparadas 70-- Jóvenes Desempleados por No Contar con el Requisito de la Libreta Militar 72-- Conclusiones 79-- Recomendaciones 81-- Referencias 84--Abogado(a)Pregrad
A review to update the protected areas in ecuador and an analysis of their main impacts and conservation strategies
No full textEstablishing new protected areas (PAs) is one of the first steps needed to reduce habitat loss and fragmentation, protect ecosystems that are of vital importance to conserve biodiversity, and even protect traditional cultures. The correct management of a PA can be beneficial for the different forms of life found within it and can provide multiple benefits to humanity and to the continued functioning of productive ecosystems. Protected Areas act as buffers for life while serving as sanctuaries and strongholds for species in the face of climate change. Within these areas, genetic diversity is enabled to evolve in response to the pressures of natural selection. The causes of biodiversity loss include changes in land use due to agriculture and urbanization, invasive species, overexploitation, and pollution. As stipulated, the current study aims to update the National System of Protected Areas (SNAP) by applying a review of scientific and gray literature. This review presents updated information; Ecuador currently has 74 protected areas, with state, decentralized autonomous, community, and private subdivisions. The main social and environmental impacts found in the protected areas included in the SNAP are presented in a review of the existing literature. Finally, strategies are proposed to improve the management of the protected areas of the SNAP focused on strengthening the conservation of their different life forms and the responsible use of their ecosystem services through more efficient and productive spaces
Tracing ΦX174 bacteriophage spreading during aerosol‑generating procedures in a dental clinic
No full textObjective The aim of this study was to test the plausibility of using the ΦX174 bacteriophage as a tracer of viral aerosols spreading in a dental aerosol-generating procedure (AGP) model. Methods ΦX174 bacteriophage (~ 108 plaque-forming units (PFU)/mL) was added into instrument irrigation reservoirs and aerosolized during class-IV cavity preparations followed by composite fllings on natural upper-anterior teeth (n=3) in a phantom head. Droplets/aerosols were sampled through a passive approach that consisted of Escherichia coli strain C600 cultures immersed in a LB top agar layer in Petri dishes (PDs) in a double-layer technique. In addition, an active approach consisted of E coli C600 on PDs sets mounted in a six-stage cascade Andersen impactor (AI) (simulating human inhalation). The AI was located at 30 cm from the mannequin during AGP and afterwards at 1.5 m. After collection PDs were incubated overnight (18 h at 37 °C) and bacterial lysis was quantifed. Results The passive approach disclosed PFUs mainly concentrated over the dental practitioner, on the mannequin’s chest and shoulder and up to 90 cm apart, facing the opposite side of the AGP’s source (around the spittoon). The maximum aerosol spreading distance was 1.5 m in front of the mannequin’s mouth. The active approach disclosed collection of PFUs corresponding to stages (and aerodynamic diameters) 5 (1.1–2.1 µm) and 6 (0.65–1.1 µm), mimicking access to the lower respiratory airways. Conclusion The ΦX174 bacteriophage can be used as a traceable viral surrogate in simulated studies contributing to understand dental bioaerosol’s behavior, its spreading, and its potential threat for upper and lower respiratory tract. Clinical relevance The probability to fnd infectious virus during AGPs is high. This suggests the need to continue characterizing the spreading viral agents in diferent clinical settings through combination of passive and active approaches. In addition, subsequent identifcation and implementation of virus-related mitigation strategies is relevant to avoid occupational virus infections
Energetic analysis in a hot water system: a hotel facility case study
No full textThis paper evaluates the energy operational performance of a system to produce domestic hot water, from the use of waste heat in a centralized air conditioning system in a hotel in Cuba. The hotel facility has two different chillers capacities, where the system recovers the condensed heat, through a heat exchanger at the compression process outlet. These schemes allow the simultaneous production of air conditioning and Domestic Hot Water, also those considering thermal storage tanks. The system modelling starts analyzing its components and their processes, based on the traditional thermodynamics and heat transfer equations and ends with a validation process. This model estimates a wide range of operating conditions, such as thermal demands of the cooling load, the chiller water temperature, the electricity consumed by chillers, and the climatological variables involved. The system is evaluated in the highest tourism season in Cuba during a year under partial load. Results were validated in a hotel as a study case, which allowed us to estimate the thermal potential available in the plant to meet the thermal demand of the hot water required, as well as showing that variations in the chiller operation affect the temperature stability in the hot water system
Artificial intelligence and discrete-event simulation for capacity management of intensive care units during the Covid-19 pandemic: a case study
No full textThe Covid-19 pandemic has pushed the Intensive Care Units (ICUs) into significant operational disruptions. The rapid evolution of this disease, the bed capacity constraints, the wide variety of patient profiles, and the imbalances within health supply chains still represent a challenge for policymakers. This paper aims to use Artificial Intelligence (AI) and Discrete-Event Simulation (DES) to support ICU bed capacity management during Covid-19. The proposed approach was validated in a Spanish hospital chain where we initially identified the predictors of ICU admission in Covid-19 patients. Second, we applied Random Forest (RF) to predict ICU admission likelihood using patient data collected in the Emergency Department (ED). Finally, we included the RF outcomes in a DES model to assist decision-makers in evaluating new ICU bed configurations responding to the patient transfer expected from downstream services. The results evidenced that the median bed waiting time declined between 32.42 and 48.03 min after intervention
Alfabetización digital fundamentada en técnicas de gamificación para el desarrollo de competencias tecnológicas en docentes y estudiantes de secundaria
No full textToday, digital literacy has become a main feature to face present and future demands to improve and strengthen digital competencies in education processes. The main objective of this research project is to design a digital literacy proposal based on gamification techniques to develop the technological competencies of secondary and middle school students and teachers. The research is a non-experimental design. It is a complementary or emergent paradigm, following a mixed approach in a descriptive-explanatory-propositional type of research. The sample selected for this study consists of seventy students and eight teachers from the secondary and middle school of Las Palmas high school: using techniques such as survey, checklist, document review on the web, implementation of the proposal and a validation rubric. The results highlight the relevance of the research and the proposal itself, to provide a solution to academic and behavioral challenges presented in students and teachers to develop technological competencies, the attachment to traditional education, the lack of the appropriate infrastructure and the use of digital resources. Upon the completion of the project, it is positive in terms of the acceptance and attitude of the participants to achieve the objectives and develop technological competencies based on digital literacy.Actualmente, la alfabetización digital se convierte en un factor determinante para enfrentar las exigencias presentes y futuras con el propósito de evolucionar y fortalecer las competencias digitales en los procesos educativos. El presente proyecto de investigación se trazó como objetivo principal diseñar una propuesta de alfabetización digital fundamentada en la técnica de gamificación para el desarrollo de competencias tecnológicas de estudiantes y docentes de educación básica secundaria y media. La investigación se enmarca en el diseño no experimental. Se sustenta bajo el paradigma complementario o emergente, con un enfoque mixto y se enmarca en una investigación de tipo descriptiva-explicativa-propositiva. La muestra seleccionada para este trabajo consiste en 70 estudiantes y 8 docentes de básica secundaria y media de la I. E. Las Palmas, usando técnicas como la encuesta, lista de chequeo, revisión documental en la web, implementación de la propuesta y rúbrica de validación. Se obtienen resultados muy satisfactorios que dejan advertir la pertinencia de la investigación y de la propuesta en sí, para brindar solución a retos académicos y actitudinales presentes en estudiantes y docentes para desarrollar competencias tecnológicas, el apego a la educación tradicional y déficit en la infraestructura y uso de recursos digitales. Al llevar a término el proyecto, es muy positivo en cuanto a la aceptación y actitud de los participantes para lograr los objetivos y desarrollar competencias tecnológicas a partir de la alfabetización digital.Lista de Tablas y Figuras 12--
Introducción 15--
Capítulo I 19--
Planteamiento del Problema 19--
Descripción del Problema 19--Formulación del Problema 28--
Objetivos 29--Objetivo general 29
Objetivos específicos 29--Justificación del Trabajo 30--
Delimitación del Trabajo de Investigación 33
Delimitación espacial 33--
Delimitación temporal 35--
Delimitación temática 35--
Hipótesis 36--
Capítulo II 37--
Marco Teórico 37--
Antecedentes de la Investigación 38--
Antecedentes internacionales 38--
Antecedentes nacionales 52--
Antecedentes locales 60--
Referentes Teóricos 67--
Marco Legal 76--
Marco Conceptual 80--
Operacionalización de las Variables 97--
Capítulo III. 117--Marco Metodológico 117--Paradigma de investigación 117
Enfoque de la investigación 119--
Tipo de investigación 123--
Diseño de la investigación 124--
Población y muestra 125--
Técnicas e instrumentos de recolección de datos 126--
Capítulo IV 135--
Análisis de los Resultados 135--
Análisis por cada uno de los objetivos, instrumentos y actores 136--
Discusión de los resultados 208--
Capítulo V 217--
Conclusiones y Recomendaciones 217--
Conclusiones 217--
Recomendaciones 220--
Capítulo VI 222--
Propuesta de Alfabetización Digital Mediada por Estrategias de Gamificación 222--
Presentación 222--
Situación Problema 223--
Objetivos 224--
Objetivo general 224--
Objetivos específicos 224--
Justificación 225--
Marco Legal 225--
Fundamentación Teórica 227--
Actores 230--
Descripción de la propuesta 230--
Etapas y Metodología de la Propuesta 232--
Validación de la propuesta 237--
Referencias 240--Magíster en Educación – Modalidad VirtualMaestrí
Application of pyrolysis for the evaluation of organic compounds in medical plastic waste generated in the city of Cartagena-Colombia applying TG-GC/MS
No full textIn this study, the thermal degradation and pyrolysis of hospital plastic waste consisting of polyethylene (PE), polystyrene (PS), and polypropylene (PP) were investigated using TG-GC/MS. The identified molecules with the functional groups of alkanes, alkenes, alkynes, alcohols, aromatics, phenols, CO and CO2 were found in the gas stream from pyrolysis and oxidation, and are chemical structures with derivatives of aromatic rings. They are mainly related to the degradation of PS hospital waste, and the alkanes and alkenes groups originate mainly from PP and PE-based medical waste. The pyrolysis of this hospital waste did not show the presence of derivatives of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, which is an advantage over classical incineration methodologies. CO, CO2, phenol, acetic acid and benzoic acid concentrations were higher in the gases from the oxidative degradation than in those generated in the pyrolysis with helium. In this article, we propose different pathways of reaction mechanisms that allow us to explain the presence of molecules with other functional groups, such as alkanes, alkenes, carboxylic acids, alcohols, aromatics and permanent gases