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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Linking morphology and physiology as predictors of productivity in elite families of southern pines

Chmura, Daniel Jozef 15 May 2009 (has links)
Crown architecture affects tree growth through the control of leaf area and its display. Yet the linkages between crown structure, leaf traits, and productivity of elite selections of forest trees and responses to intensive silviculture are not fully understood. It was hypothesized that trees with crown and leaf traits governing efficient light capture and photosynthesis at the canopy scale would be the most productive. To this end, families of loblolly (Pinus taeda) and slash pine (Pinus elliottii) were grown at three experimental sites in the West Gulf Coastal Plain of Texas and Louisiana under two silvicultural treatments, including repeated fertilization with control of competing vegetation (HI), and a control (C) consisting of fertilization at planting. Families and species differed in crown traits and aboveground productivity, and genotype differences increased throughout the first 5 years of stand development. Crown shape was important for light interception and growth initially, but at the onset of canopy closure, crown size, stand leaf area and its distribution within crowns affected canopy light interception and tree growth. Among all families and treatments, aboveground biomass productivity was positively related to absorbed photosynthetically active radiation (APAR) and canopy photosynthesis. Light-use efficiency (ε) varied from 0.41 to 0.56 g MJ-1 among families and was lowest in slash pine. Variability in aboveground biomass growth was related more to stand leaf area and APAR than to differences in light-use efficiency in these young stands. Leaf physiological, chemical and morphological attributes changed within crowns in accordance with developing light availability gradients. Physiological attributes, such as net photosynthesis, were better predictors of family performance when integrated at the canopy level than leaf level in the examined pine species. Crown size, light absorption, and aboveground growth generally ranked higher in the HI treatment than in the control, although the effects of the intensive silvicultural treatments did not differ statistically. Family performance was independent of treatment. Crown and canopy attributes, such as high leaf area index and large crowns with low leaf area density per crown volume, may be useful in the selection of highly productive genotypes of loblolly and slash pine under intensive silviculture.
2

Linking morphology and physiology as predictors of productivity in elite families of southern pines

Chmura, Daniel Jozef 15 May 2009 (has links)
Crown architecture affects tree growth through the control of leaf area and its display. Yet the linkages between crown structure, leaf traits, and productivity of elite selections of forest trees and responses to intensive silviculture are not fully understood. It was hypothesized that trees with crown and leaf traits governing efficient light capture and photosynthesis at the canopy scale would be the most productive. To this end, families of loblolly (Pinus taeda) and slash pine (Pinus elliottii) were grown at three experimental sites in the West Gulf Coastal Plain of Texas and Louisiana under two silvicultural treatments, including repeated fertilization with control of competing vegetation (HI), and a control (C) consisting of fertilization at planting. Families and species differed in crown traits and aboveground productivity, and genotype differences increased throughout the first 5 years of stand development. Crown shape was important for light interception and growth initially, but at the onset of canopy closure, crown size, stand leaf area and its distribution within crowns affected canopy light interception and tree growth. Among all families and treatments, aboveground biomass productivity was positively related to absorbed photosynthetically active radiation (APAR) and canopy photosynthesis. Light-use efficiency (ε) varied from 0.41 to 0.56 g MJ-1 among families and was lowest in slash pine. Variability in aboveground biomass growth was related more to stand leaf area and APAR than to differences in light-use efficiency in these young stands. Leaf physiological, chemical and morphological attributes changed within crowns in accordance with developing light availability gradients. Physiological attributes, such as net photosynthesis, were better predictors of family performance when integrated at the canopy level than leaf level in the examined pine species. Crown size, light absorption, and aboveground growth generally ranked higher in the HI treatment than in the control, although the effects of the intensive silvicultural treatments did not differ statistically. Family performance was independent of treatment. Crown and canopy attributes, such as high leaf area index and large crowns with low leaf area density per crown volume, may be useful in the selection of highly productive genotypes of loblolly and slash pine under intensive silviculture.
3

Ilustración artística con marcadores Pitt artist pen

Castellanos, Luis 24 November 2021 (has links)
Clase maestra de ilustración artística con el Embajador de marca Faber-Castell Luis Castellanos
4

Bilingual elementary teachers : examining pedagogy and literacy practices

Garza, Irene Valles 09 February 2015 (has links)
This study is significant because U.S. schools are continuously being transformed due to the increasing numbers of linguistically and culturally diverse students, in particular Latina/o youths. Therefore, this qualitative dissertation study explored and described ways three Latina Tejana Maestras utilized Culturally Responsive Pedagogy (CRP) during literacy learning as they integrated students’ knowledge about their social and cultural environment, including their native language repertoire, while developing and implementing instruction. This study used sociocultural and borderlands theoretical construct to explore and describe ways the Maestras enacted and sustained CRP during literacy events. The sociocultural perspective is a fitting lens because it takes into account how knowledge is constructed in and through social interaction. Borderlands is also a fitting lens because it takes into account the Tejana Maestras borderlands identity of straddling simultaneous worlds — two languages, two cultures. Sociocultural theory and Borderlands theoretical lenses were complemented by CRP, a teaching approach that not only fits the school culture to the students’ culture, but uses the students’ culture as the basis for students to understand themselves and guiding them to becoming academically successful. The two questions used to guide this dissertation were: What culturally responsive pedagogical knowledge and practices do Tejana Maestras enact in bilingual classrooms? Second: How do Tejana Maestras acquire knowledge about the culture, language, and background experience of their students when planning and implementing instruction? The research revealed three themes, a) the presence of Building a Bilingual Classroom Community (BBCC) that was continuously evolving, and seamlessly functioning, as a system was clearly evident in each of the three classrooms, b) the Tejana Maestras notion of agents of change that guided their pedagogical literacy practices, and c) the notion of centering Mexican American students’ values, beliefs, and norms into the pedagogy and curriculum responsive to emergent bilinguals was recognizable. Six findings developed from the data; a) Tejana Maestras foster cultural awareness, b) embrace Latina/o bilingualism, c) employ a menu of culturally responsive literacy practices, d) learn from their students e) are conscious of their identity, and f) teaching philosophy. Due to U.S. schools being transformed by the increasing numbers of linguistically and culturally diverse students, the study demonstrated that it is important to conduct research about Tejana Maestras to learn the ways they are effectively meeting the needs of bilingual students by using CRP to promote academic success. / text
5

Un utile e stabile occupazione : Le origini della professione di maestra nella Lombardia della Restaurazione

TATULLI, NATALIA 21 March 2012 (has links)
Per soddisfare la domanda educativa per le ragazze dei ceti più agiati il governo napoleonico diede corso oltre all’apertura dei noti collegi Reali ad un sistema di case d’educazione private ispirate al modello delle maisons d’éducation con convitto diffuse in Francia, già a partire dagli ultimi decenni del Settecento, e dirette da donne laiche. In Lombardia, con il ritorno degli Asburgo, questo modello formativo per fanciulle si consolidò e conquistò una fetta sempre più ampia del mercato educativo. Inoltre accanto a questi istituti videro una enorme crescita le scuole private giornaliere per fanciulle dirette da maestre laiche, le quali si diffusero a partire dall’entrata in vigore del Regolamento per le scuole elementari del 1818 parallelamente al lento affermarsi dell’istruzione pubblica femminile. L’elevato numero di donne coinvolte in questa attività (più di 2200 dal 1818 al 1848) e l’obbligo di sostenere degli esami e seguire un iter formativo standardizzato sia per l’insegnamento privato che per l’insegnamento pubblico, dimostrano come la figura della maestra, selezionata attraverso un esame e un percorso formativo ad hoc non comparve in Italia a partire dall’Unità, ma, in particolare nel Regno Lombardo-Veneto, fosse già ampiamente diffusa e socialmente e pubblicamente riconosciuta a partire dagli anni Venti dell’Ottocento. / The rise of women as teaching professionals in Restoration Lombardy. In order to satisfy the large number of application requests from girls of the wealthiest classes, the Napoleonic government started, besides the well known Real colleges, a system of boarding school directed by laywomen, inspired by the model of the maisons d’éducation boarding schools which were already popular in France since the last decades of the 18th century. With the return of the Asburgos family in Lombardy ,those institutes increased as well as daily private schools for young girl directed by layteachers. As those private schools became popular pretty fast, the affirmation of the feminine public teaching was very slow. The big amount of women committed in this activity (more than 2200 from 1818 to 1848), the compulsoriness of examinations and to follow a standardized formative iter,shows how the role of the teacher,selected by exams and by a specific formative training, didn't start in Italy with the unification ,but -especially in the Kingdom of Lombardy–Venetia -was already diffused and recognized both socially and publicly from the first decades of 18th century.
6

Aplicación de last planner en edificaciones multifamiliares

Hinostroza Gutiérrez, Diego Alberto, Manosalva Montesinos, Oscar Omar January 2015 (has links)
A través del programa Maestro (programación macro), se analizará el proceso de planificación Intermedia o Look ahead Planning, sucedido por el plan de trabajo semanal y diario. La planificación intermedia (proceso Look ahead) es una expansión del programa maestro, que genera un programa de trabajo que, pensamos, puede ser ejecutado usando información del estado actual del proyecto y pronósticos sobre la disponibilidad de recursos. Como se sabe, el programa Maestro cubre todas las actividades del proyecto, desde el comienzo hasta el término del mismo. En cambio, la planificación Look ahead abarca intervalos de sólo 4 a 8 semanas, según la complejidad del proyecto, en el futuro con relación a la fecha de la planificación porque la incertidumbre sobre lo que vendrá después deja sin sentido un mayor detalle. El plan de trabajo semanal es la planificación que presenta el mayor nivel de detalle antes de realizar una actividad. Escoger qué trabajo será ejecutado en la próxima semana desde lo que sabemos puede ser hecho, recibe el nombre de asignaciones de calidad. Sólo asignaciones de calidad pueden entrar en un inventario de trabajo ejecutable y posteriormente al plan de trabajo semanal, lo que protege el flujo de producción de incertidumbres, lo que apunta a crear un flujo confiable de trabajo. Para ello se tomó como estudio el edificio multifamiliar las Dalias, donde se explica detalladamente la aplicación de look ahead de la semana 19 donde se realizó el vaciado de losa del sótano 2 y se detalla el análisis de programación semanal con sus posibles restricciones y recursos para poder resolverlas, demostrando con ello que aplicando el Last Planner se maximiza la producción y se minimizan los costos. Through the Master program (macro programming), the mid-term planning or Look ahead Planning, succeeded by the weekly plan and daily work will be analyzed. The intermediate planning (Look ahead process) is an expansion of master program, which generates a work program that we think can be executed using information of the current project status and forecasts on the availability of resources. As is known, the Master program covers all activities of the project from the beginning to the end of it. However, planning ahead Look intervals covers only 4-8 weeks, depending on the complexity of the project in the future in relation to the planning date because uncertainty about what comes next makes it meaningless greater detail. The weekly work plan is the planning that has the highest level of detail before an activity. Choose what work will be executed in the next week from what we know can be done, is called quality assignments. Only quality assignments can enter an inventory of executable work and then to plan weekly work, protecting the flow of production uncertainties, which aims to create a reliable workflow. For this study was taken as the multifamily building Dahlias, which explains in detail the implementation of look ahead to week 19 where the drain basement slab 2 was performed and analysis of weekly programming with the possible restrictions and resources for detailed to resolve them, demonstrating that applying the Last Planner maximizing production and minimizing cost.
7

Ecologia da produção e da competição intra-específica do Eucalyptus grandis ao longo de um gradiente de produtividade no estado de São Paulo / Production ecology and intra-specific competition of Eucalyptus grandis across a gradient of productivity in São Paulo State

Campoe, Otávio Camargo 13 February 2012 (has links)
A produtividade dos plantios de eucalipto no Brasil apresentou ganhos significativos nas últimas décadas devido a avanços em melhoramento genético e silvicultura. Contudo, a produção de madeira representa apenas uma fração da produtividade primária bruta (GPP). Avaliar fluxos e partição de carbono (C) entre os diferentes componentes da floresta, e estudar o uso e a eficiência de uso dos recursos disponíveis é essencial para compreender os mecanismos que controlam a produtividade de plantios intensivamente manejados. O estudo quantificou os fluxos e partição de C e a eficiência de uso da luz para a produção de lenho (LUE) em 12 parcelas em um gradiente natural de produtividade, durante o sétimo ano de um plantio comercial de Eucalyptus grandis. Nessas mesmas parcelas, na escala da árvore, foram avaliadas a dominância do crescimento, produção de lenho e LUE, identificando a representatividade de árvores dominantes e suprimidas na produtividade do povoamento. O estudo do balanço de C e a aplicação da teoria da ecologia da produção em diferentes escalas objetivaram ampliar o conhecimento sobre os processos que governam a produtividade florestal. A heterogeneidade espacial dos atributos do solo e a topografia da área experimental influenciaram fortemente os fluxos componentes da GPP e sua partição, gerando um gradiente de produtividade. A produtividade de lenho variou de 554 gC m-2 ano-1 na parcela com menor GPP a 923 gC m-2 ano-1 na parcela com maior GPP. O fluxo de C para o solo variou de 497 gC m-2 ano-1 a 1235 gC m-2 ano-1 sem relação significativa com GPP. A partição do GPP para produção de lenho aumentou de 0,19 a 0,23, com tendência de aumento com o GPP (R2=0,30, p=0,07). A LUE aumentou em 66% (de 0,25 gC MJ-1 para 0,42 gC MJ-1) com a GPP, como resultado da elevação do fluxo e partição de C para produção de lenho. Ao longo do gradiente de produtividade, parcelas com alta eficiência quântica do dossel também mostraram alta LUE. A dominância do crescimento entre árvores teve forte impacto sobre a produtividade do povoamento. As 20% maiores árvores apresentaram em média 38% da biomassa de lenho e representaram 47% da produção de lenho. Características das folhas sugeriram que a maior produtividade de árvores dominantes, em relação às suprimidas, pode resultar de diferenças no controle estomático e não na capacidade fotossintética. A ecologia da produção na escala da árvore mostrou que os indivíduos dominantes produziram mais madeira por terem absorvido mais radiação e pela maior eficiência do uso da luz, comparativamente às árvores suprimidas. Em média, uma árvore suprimida cresceu 1,2 kg ano-1 de lenho, absorveu 2,9 GJ ano-1 de radiação e teve uma LUE de 0,4 g MJ-1. Já uma dominante cresceu 37 kg ano-1, absorveu 38 GJ ano-1 com mais que o dobro da eficiência (1,01 g MJ-1). Estudos sobre o balanço de carbono e ecologia da produção em diferentes escalas são essenciais para aperfeiçoar o conhecimento sobre os processos que controlam a produtividade de madeira e a fixação de carbono, e aprimorar os modelos ecofisiológicos. / The productivity of the eucalypt plantations in Brazil showed significant increase over the last decades, due to improvement in breeding and silviculture. However, wood production represents only a fraction of the gross primary production (GPP). Assessing carbon (C) fluxes and partitioning among forest components, and evaluate use and use efficiency of the available resources is essential to understand mechanisms driving productivity of intensively managed plantations. The study quantified fluxes and partitioning of C and light use efficiency for stem production (LUE) in 12 plots across a natural gradient of productivity during the seventh year of a commercial Eucalyptus grandis. Within these plots, at tree level, were evaluated growth dominance, stem production and LUE, identifying representativeness of dominant and suppressed trees to stand productivity. The study of C budget and the application of the production ecology theory at different levels aimed increase the knowledge about the processes driving forest productivity. The spatial heterogeneity of soil attributes and topography across the experimental site strongly influenced the component fluxes of GPP and partitioning, generating a gradient of productivity. Stem production ranged from 554 gC m-2 year-1 at the lowest GPP plot to 923 gC m-2 year-1 at the highest GPP plot. Total below ground carbon flux (TBCF) ranged from 497 g C m-2 year-1 to 1235 g C m-2 year-1, with no relationship to ANPP or GPP. Stem NPP:GPP partitioning ratio increased from 0.19 to 0.23 showing a trend of increase with GPP (R2=0.30, p=0.07). LUE increased by 66% (from 0.25 gC MJ-1 to 0.42 gC MJ-1) with GPP, as a result of the increased C partitioned and flux to stem NPP. Across the gradient of productivity, plots with the highest canopy quantum efficiency also showed the highest LUE. Growth dominance between trees showed a strong impact on stand productivity. The 20% larger trees accounted for 38% of stem biomass and represented 47% stem production. Leaf characteristics suggested that dominant trees were more productive, in relation to suppressed, may result in differences on stomatal control and not on photosynthetic capacity. The production ecology at tree level showed that dominant trees produced more wood by absorbing more radiation and due to higher light use efficiency, comparing to suppressed trees. On average, a suppressed tree grew 1,2 kg year-1 of stem, absorbed 2,9 GJ year-1 of radiation with a LUE of 0.4 g MJ-1. Although, a dominant grew 37 kg year-1 of stem, absorbed 38 GJ year-1 of radiation with the double of efficiency (1.01 g MJ-1). Studies regarding carbon balance and production ecology at different levels are essential to improve the knowledge on processes controlling wood production and carbon uptake, and develop ecophysiological models.
8

Ecologia da produção e da competição intra-específica do Eucalyptus grandis ao longo de um gradiente de produtividade no estado de São Paulo / Production ecology and intra-specific competition of Eucalyptus grandis across a gradient of productivity in São Paulo State

Otávio Camargo Campoe 13 February 2012 (has links)
A produtividade dos plantios de eucalipto no Brasil apresentou ganhos significativos nas últimas décadas devido a avanços em melhoramento genético e silvicultura. Contudo, a produção de madeira representa apenas uma fração da produtividade primária bruta (GPP). Avaliar fluxos e partição de carbono (C) entre os diferentes componentes da floresta, e estudar o uso e a eficiência de uso dos recursos disponíveis é essencial para compreender os mecanismos que controlam a produtividade de plantios intensivamente manejados. O estudo quantificou os fluxos e partição de C e a eficiência de uso da luz para a produção de lenho (LUE) em 12 parcelas em um gradiente natural de produtividade, durante o sétimo ano de um plantio comercial de Eucalyptus grandis. Nessas mesmas parcelas, na escala da árvore, foram avaliadas a dominância do crescimento, produção de lenho e LUE, identificando a representatividade de árvores dominantes e suprimidas na produtividade do povoamento. O estudo do balanço de C e a aplicação da teoria da ecologia da produção em diferentes escalas objetivaram ampliar o conhecimento sobre os processos que governam a produtividade florestal. A heterogeneidade espacial dos atributos do solo e a topografia da área experimental influenciaram fortemente os fluxos componentes da GPP e sua partição, gerando um gradiente de produtividade. A produtividade de lenho variou de 554 gC m-2 ano-1 na parcela com menor GPP a 923 gC m-2 ano-1 na parcela com maior GPP. O fluxo de C para o solo variou de 497 gC m-2 ano-1 a 1235 gC m-2 ano-1 sem relação significativa com GPP. A partição do GPP para produção de lenho aumentou de 0,19 a 0,23, com tendência de aumento com o GPP (R2=0,30, p=0,07). A LUE aumentou em 66% (de 0,25 gC MJ-1 para 0,42 gC MJ-1) com a GPP, como resultado da elevação do fluxo e partição de C para produção de lenho. Ao longo do gradiente de produtividade, parcelas com alta eficiência quântica do dossel também mostraram alta LUE. A dominância do crescimento entre árvores teve forte impacto sobre a produtividade do povoamento. As 20% maiores árvores apresentaram em média 38% da biomassa de lenho e representaram 47% da produção de lenho. Características das folhas sugeriram que a maior produtividade de árvores dominantes, em relação às suprimidas, pode resultar de diferenças no controle estomático e não na capacidade fotossintética. A ecologia da produção na escala da árvore mostrou que os indivíduos dominantes produziram mais madeira por terem absorvido mais radiação e pela maior eficiência do uso da luz, comparativamente às árvores suprimidas. Em média, uma árvore suprimida cresceu 1,2 kg ano-1 de lenho, absorveu 2,9 GJ ano-1 de radiação e teve uma LUE de 0,4 g MJ-1. Já uma dominante cresceu 37 kg ano-1, absorveu 38 GJ ano-1 com mais que o dobro da eficiência (1,01 g MJ-1). Estudos sobre o balanço de carbono e ecologia da produção em diferentes escalas são essenciais para aperfeiçoar o conhecimento sobre os processos que controlam a produtividade de madeira e a fixação de carbono, e aprimorar os modelos ecofisiológicos. / The productivity of the eucalypt plantations in Brazil showed significant increase over the last decades, due to improvement in breeding and silviculture. However, wood production represents only a fraction of the gross primary production (GPP). Assessing carbon (C) fluxes and partitioning among forest components, and evaluate use and use efficiency of the available resources is essential to understand mechanisms driving productivity of intensively managed plantations. The study quantified fluxes and partitioning of C and light use efficiency for stem production (LUE) in 12 plots across a natural gradient of productivity during the seventh year of a commercial Eucalyptus grandis. Within these plots, at tree level, were evaluated growth dominance, stem production and LUE, identifying representativeness of dominant and suppressed trees to stand productivity. The study of C budget and the application of the production ecology theory at different levels aimed increase the knowledge about the processes driving forest productivity. The spatial heterogeneity of soil attributes and topography across the experimental site strongly influenced the component fluxes of GPP and partitioning, generating a gradient of productivity. Stem production ranged from 554 gC m-2 year-1 at the lowest GPP plot to 923 gC m-2 year-1 at the highest GPP plot. Total below ground carbon flux (TBCF) ranged from 497 g C m-2 year-1 to 1235 g C m-2 year-1, with no relationship to ANPP or GPP. Stem NPP:GPP partitioning ratio increased from 0.19 to 0.23 showing a trend of increase with GPP (R2=0.30, p=0.07). LUE increased by 66% (from 0.25 gC MJ-1 to 0.42 gC MJ-1) with GPP, as a result of the increased C partitioned and flux to stem NPP. Across the gradient of productivity, plots with the highest canopy quantum efficiency also showed the highest LUE. Growth dominance between trees showed a strong impact on stand productivity. The 20% larger trees accounted for 38% of stem biomass and represented 47% stem production. Leaf characteristics suggested that dominant trees were more productive, in relation to suppressed, may result in differences on stomatal control and not on photosynthetic capacity. The production ecology at tree level showed that dominant trees produced more wood by absorbing more radiation and due to higher light use efficiency, comparing to suppressed trees. On average, a suppressed tree grew 1,2 kg year-1 of stem, absorbed 2,9 GJ year-1 of radiation with a LUE of 0.4 g MJ-1. Although, a dominant grew 37 kg year-1 of stem, absorbed 38 GJ year-1 of radiation with the double of efficiency (1.01 g MJ-1). Studies regarding carbon balance and production ecology at different levels are essential to improve the knowledge on processes controlling wood production and carbon uptake, and develop ecophysiological models.
9

PLANIFICACIÓN MAESTRA DE OPERACIONES EN LA GESTIÓN DE LA CADENA DE SUMINISTRO EN CONTEXTO DE INCERTIDUMBRE EN EL SECTOR CERÁMICO. PROPUESTA DE MODELADO Y RESOLUCIÓN BASADA EN REDES NEURONALES ARTIFICIALES (ANN)

Mena O'Meara, Nicolay Antonio 30 December 2010 (has links)
La Planificación Colaborativa en la Cadena/Red de Suministro (C/RS) en un Contexto de Incertidumbre necesita de nuevos sistemas que minimicen la aleatoriedad a lo largo de ésta. La incertidumbre se puede tratar a partir de algoritmos heurísticos que mejoran las actividades logísticas que comprenden la Planificación Maestra de la Cadena, obteniendo así mejores resultados en cuanto a margen de beneficios, minimización de costes y otros objetivos que se persiguen en la Cadena. Todo esto para obtener la colaboración entre las diferentes etapas (Proveedor, Fabricación, Distribución y Detallista) que comprende la Cadena de Suministro. En este enfoque, de Tesis presenta una Propuesta Metodológica que se compone de una Propuesta de Modelado, la Descripción del Problema, dos modelos matemáticos (Determinista y de Incertidumbre), la Implantación del Modelado, la Arquitectura y la Plataforma Tecnológica SCANN (Supply Chain Artificial Neuronal Networks), y por último, la Aplicación del Modelo y la Herramienta de Resolución a una Empresa. En lo que se refiere a los dos modelos matemáticos de optimización (Modelo Matemático Determinista "MMD" y Modelo Matemático con Incertidumbre "MMI"), estos consideran simultáneamente la maximización del margen de beneficios para compararlos entre sí. Un modelo está construido en el contexto determinista y el otro utiliza el mismo modelo determinista pero aplicándole incertidumbre, la cual se prevé con Redes Neuronales (las Redes Neuronales prevén un mejor resultado a partir de su proceso interno y entrenamiento de datos). Los modelos MMD, MMI, y las Redes Neuronales están implantados en una Plataforma Tecnológica SCANN (desarrollada por el doctorando), la cual está aplicada al sector cerámico con la ventaja de poder ser utilizada para diferentes modelos de Cadena de Suministro. La Plataforma Tecnológica SCANN ayuda a la Toma de Decisiones en una C/RS centralizada a un nivel Táctico-Operativo. / Mena O'meara, NA. (2010). PLANIFICACIÓN MAESTRA DE OPERACIONES EN LA GESTIÓN DE LA CADENA DE SUMINISTRO EN CONTEXTO DE INCERTIDUMBRE EN EL SECTOR CERÁMICO. PROPUESTA DE MODELADO Y RESOLUCIÓN BASADA EN REDES NEURONALES ARTIFICIALES (ANN) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/9088 / Palancia
10

Métodos y modelos para la planificación de operaciones en cadenas de suministro caracterizadas por la falta de homogeneidad en el producto. Aplicación al sector cerámico

Mundi Sancho, María Isabel 22 September 2018 (has links)
Tesis por compendio / [EN] Lack of Homogeneity in the Product (LHP) appears in some production processes which incorporate raw materials coming directly from nature and/or production processes with operations which cause some heterogeneity in the characteristics of the outputs obtained respect to certain attributes. The result is the existence of several references (subtypes) of the same product which differ in some characteristics relevant to customers and this aspect becomes a problem when customers require homogeneous units in their orders. Supply Chains (SC) in sectors with this problem, such as ceramic, wood, textiles, fruit or meat, among others, are forced to include one or more classification stages along the production process whose location and classification criteria depend on each specific sector. The classification of the same element in several subtypes increases the number of references and the volume of information to process, complicating management system. In addition, after each classification stage, the quantity of each subtype will only be known after the production is finished which introduces a new type of LHP inherent uncertainty: uncertainty in the quantities of each subtype in different planned lots. This uncertainty is a problem when the customer orders must commit and be served from homogeneous units. The Master Plan is one of the main inputs to the order promising process so that in this case, it is crucial that the Master Plan in its definition, considers and anticipates as accurately as possible the homogeneous quantities of the same product that will be available to serve the customer not only in time and quantity, but also the required homogeneity. In this thesis, it is proposed as main objective to develop methods and models for master planning of operations in SC with LHP dealing with its inherent uncertainty associated. To achieve this, the problem of LHP is characterized and its impact is identified in the planning process operations. This base serves for the development of mathematical programming models for master planning of SC with LHP in deterministic and uncertain contexts. Through these models the size of the production batch is defined considering their division into homogeneous quantities and the uncertainty associated with the objective of serving the customer demand with homogeneous units. A support system to decision-making that facilitates the proposal of different scenarios as an alternative approach to the treatment of uncertainty is also proposed. All models are validated in the ceramic sector. The results show that the gross margin and the level of customer service improves when taking into account in planning models both characteristics due to the LHP and its associated uncertainty. / [ES] La Falta de Homogeneidad en el Producto (FHP) aparece en algunos procesos productivos que incorporan materias primas procedentes directamente de la naturaleza y/o procesos productivos con operaciones que provocan cierta heterogeneidad en las características de los productos obtenidos en relación con ciertos atributos. El resultado es la existencia de varias referencias (subtipos) del mismo producto que son diferentes en algunas características relevantes para los clientes y este aspecto se convierte en un problema cuando los clientes requieren unidades homogéneas en sus pedidos. Las Cadenas de Suministro (CdS) en los sectores con esta problemática, como el cerámico, maderero, textil, frutícola, o cárnico, entre otros, se ven obligadas a incluir una o varias fases de clasificación a lo largo del proceso productivo cuya localización y criterios de clasificación, dependen de cada sector específico. La clasificación de un mismo ítem en varios subtipos aumenta el número de referencias a manejar y el volumen de información a procesar, lo que complica la gestión del sistema. Además, después de cada etapa de clasificación, la cantidad obtenida de cada subtipo sólo se conoce con posterioridad a su producción lo que introduce un nuevo tipo de incertidumbre inherente a la FHP: la incertidumbre en las cantidades de cada subtipo de los diferentes lotes de producción planificados. Esta incertidumbre supone un problema cuando los pedidos de los clientes deben comprometerse y servirse a partir de unidades homogéneas. El Plan Maestro constituye una de las principales entradas al proceso de comprometer pedidos por lo que, en este caso, es crucial que el Plan Maestro en su definición considere y anticipe con la mayor exactitud posible las cantidades homogéneas de un mismo producto que estarán disponibles con objeto de servir al cliente no sólo en fecha y cantidad, sino también con la homogeneidad requerida. En esta Tesis, se plantea como objetivo principal desarrollar métodos y modelos para la planificación maestra de operaciones en las CdS con FHP que traten su incertidumbre inherente asociada. Para conseguirlo, se caracteriza la problemática de la FHP y se identifica su impacto en el proceso de planificación de operaciones. Esta base sirve para el desarrollo de modelos de programación matemática para la planificación maestra de cadenas de suministro con FHP en contextos determinista e incierto. A través de estos modelos se define el tamaño de los lotes de producción considerando su división en cantidades homogéneas así como su incertidumbre asociada con el objetivo de servir la demanda de los clientes con unidades homogéneas. También se propone un sistema de ayuda a la toma de decisiones que facilita el planteamiento de distintos escenarios como un enfoque alternativo al tratamiento de la incertidumbre. Todos los modelos se validan en el sector cerámico. Los resultados obtenidos muestran que el margen bruto y el nivel de servicio al cliente mejoran cuando se contemplan en los modelos de planificación tanto las características debidas a la FHP como su incertidumbre asociada. / [CA] La Falta d'Homogeneïtat en el Producte (FHP) apareix en alguns processos productius que incorporen matèries primeres procedents directament de la naturalesa i/o processos productius amb operacions que provoquen certa heterogeneïtat en les característiques dels productes obtinguts en relació amb certs atributs. El resultat és l'existència de diverses referències (subtipus) del mateix producte que són diferents en algunes característiques rellevants als clients i este aspecte es convertix en un problema quan els clients requerixen unitats homogènies en els seus comandes. Les Cadenes de Subministrament (CdS) en els sectors amb aquesta problemàtica, com el ceràmic, fuster, tèxtil, fruitícola, o càrnic, entre uns altres, es veuen obligades a incloure una o diverses fases de classificació al llarg del procés productiu la localització del qual així com els criteris de classificació, depenen de cada sector específic. La classificació d'un mateix ítem en diversos subtipus augmenta el nombre de referències i el volum d'informació a processar, la qual cosa complica la gestió del sistema. A més, després de cada etapa de classificació, la quantitat de cada subtipus només es coneix amb posterioritat a la seua producció lo que introduïx un nou tipus d'incertesa inherent a la FHP: la incertesa en les quantitats de cada subtipus dels diferents lots de producció planificats. Esta incertesa suposa un problema quan les comandes dels clients han de comprometre's i servir-se a partir d'unitats homogènies. El Pla Mestre constituïx una de les principals entrades al procés de comprometre comandes pel que, en este cas, és crucial que el Pla Mestre en la seua definició considere i anticipe amb la major exactitud possible les quantitats homogènies d'un mateix producte que estarán disponibles a fi de servir al client no sols en data i quantitat, sinó també amb l'homogeneïtat requerida. En esta Tesi, es planteja com a objectiu principal desenrotllar mètodes i models per a la planificació mestra d'operacions en les CdS amb FHP que tracten la seua incertesa inherent associada. Per a aconseguir-ho, es caracteritza la problemàtica de la FHP i s'identifica el seu impacte en el procés de planificació d'operacions. Esta base servix per al desenrotllament de models de programació matemàtica per a la planificació mestra de CdS amb FHP en contextos determinista i incert. A través d'estos models es definix la grandària dels lots de producció considerant la seua divisió en quantitats homogènies així com la seua incertesa associada amb l'objectiu de servir la demanda dels clients amb unitats homogènies. També es proposa un sistema d'ajuda a la presa de decisions que facilita el plantejament de distints escenaris com un enfocament alternatiu al tractament de la incertesa. Tots els models es validen en el sector ceràmic. Els resultats obtinguts mostren que el marge brut i el nivell de servici al client milloren quan es contemplen en els models de planificació tant les característiques degudes a la FHP com la seua incertesa associada. / Mundi Sancho, MI. (2016). Métodos y modelos para la planificación de operaciones en cadenas de suministro caracterizadas por la falta de homogeneidad en el producto. Aplicación al sector cerámico [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/72865 / TESIS / Compendio

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