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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.
171

Exterior ballistics analysis for rocket propelled KE-penetrator - A conceptual simulation study within fluid mechanics and flight mechanics / Ytterballistik för raketdriven KE-pil – En konceptuell studie inom strömnings- och flygmekanik

Wegberg, Emil January 2022 (has links)
This study has investigated the conceptual feasibility of a rocket propelled kinetic energy penetrator (KEP), designed for the handheld recoilless rifle Carl-Gustaf® 84 mm calibre system, from an exterior ballistics perspective. The methodology is based upon evaluating the aerodynamic properties of different conceptual design proposals through CFD-simulations and then performing trajectory analysis to assess their exterior ballistic performance. In particular, the main focus has been to optimize the stability, velocity and spin rate of the KEP. The results of the study indicates that the final chosen KEP design retains, from an aerodynamic perspective, longitudinal stability for Mach numbers up to 4.5, regardless if the rocket motor is ignited or not. Furthermore, if using NK1384 propellant, the final chosen design in the study is, according to the calculations, able to achieve a maximum velocity of 0.7⋅v_ref and retain a minimum velocity of 0.628⋅v_ref in the horizontal range of [0.318⋅x_ref,0.648⋅x_ref] measured from the shooter. In addition, the angular spin velocity achieves a maximum value of 15.5 Hz, satisfying the performance limitation of the rocket motor which only functions properly for frequencies up to 30 Hz, while simultaneously providing a sufficiently considered spin rate in order to average possible thrust and mass deviations of the KEP. The results also show that if using ammonium dinitramide (ADN) propellant, the KEP is able to achieve a maximum velocity of 0.786⋅v_ref, retain a minimum velocity of 0.628⋅v_ref in the horizontal range of [0.28⋅x_ref,0.98⋅x_ref] and achieve a maximum spin rate of 17.5 Hz. / Den här studien har på ett konceptuellt plan undersökt om det är möjligt att konstruera en raketdriven kinetisk energi-pil (KE-pil), designad för det rekylfria Carl-Gustaf® 84 mm granatgeväret. Studiens metod grundade sig i att undersöka olika konceptuella designförslag och utvärdera deras aerodynamiska egenskaper genom CFD-simulationer för att sedan genomföra bansimuleringar och bedöma deras ytterballistiska prestanda. Framför allt fokuserades det på att optimera KE-pilens stabilitet, hastighet och rollvinkelfrekvens. Resultaten från studien indikerar att det ur ett aerodynamiskt perspektiv är möjligt att statiskt stabilisera KE-pilen för Machtal upp till 4.5, oavsett om raketmotorn är antänd eller ej. Vidare, vid implementering av NK1384-krut lyder prestandaspecifikationerna enligt följande för studiens slutgiltiga designförslag enligt genomförda beräkningar. Den maximalt uppnådda hastigheten är 0.7⋅v_ref och en minimumhastighet om 0.628⋅v_ref kan upprätthållas inom det horisontella intervallet [0.318⋅x_ref,0.648⋅x_ref ] räknat ifrån skytten. Vidare uppnås en maximal rollvinkelfrekvens på 15.5 Hz, vilket tillfredsställer raketmotorns prestandabegränsning om en maximal rollvinkelfrekvens på 30 Hz, samtidigt som detta är en god frekvens för att utjämna eventuella avvikelser från raketmotors avsedda massflödesriktning tillika avsedd massdistribution hos KE-pilen. Om krutet i stället byts ut till ammoniumdinitramid (ADN) kan en maximal hastighet om 0.786⋅v_ref uppnås, en minimumhastighet om 0.628⋅v_ref kan upprätthållas inom intervallet [0.28⋅x_ref,0.98⋅x_ref ] och den maximala rollfrekvensen är 17.5 Hz.
172

The development of a hybrid knowledge-based system for the design of a Low Volume Automotive Manufacturing (LVAM) system

Mohamed, N.M.Z.Nik, Khan, M. Khurshid January 2012 (has links)
No / A conceptual design approach is an important stage for the development of a hybrid Knowledge-Based System (KBS) for Low Volume Automotive Manufacturing (LVAM). The development of a hybrid KBS, which is a blend of KBS and Gauging Absences of Pre-requisites (GAP), is proposed for LVAM research. The hybrid KB/GAP system identifies all potential elements of LVAM issues throughout the development of this system. The KBS used in the system design stage of the LVAM system analyses the gap between the existing and the benchmark organisations for an effective implementation through the GAP analysis technique. The proposed KBLVAM model at the design stage explores three major components, namely LVAM car body parts manufacturing perspective, LVAM competitive priorities perspective and LVAM lean environment perspective. Initial results reveal that the KBLVAM system has identified, for each perspective modules and sub-modules, the Problem Categories (PC) in a prioritised manner. / The financial support by the Malaysian Government, Universiti Malaysia Pahang and University of Bradford for this research is grateful acknowledged.
173

Diseño generativo asistido por computador. Desarrollo de una herramienta innovadora de ayuda a la exploración de soluciones conceptuales en productos

Acosta Zazueta, Gonzalo Rafael 11 April 2024 (has links)
[ES] En el transcurso de la presente tesis doctoral, se llevó a cabo la tarea de analizar el desarrollo del diseño generativo a lo largo del tiempo y en diversos campos de aplicación. Durante esta exploración, se identificó una carencia significativa de herramientas CAD de apoyo en la etapa temprana del diseño conceptual. La ausencia de recursos para facilitar la creación de diseños conceptuales básicos y la generación de diversas soluciones de diseño se presenta como un problema evidente en este contexto. El objetivo principal de la investigación es desarrollar una herramienta que aborde eficientemente esta carencia y proporcione asistencia al diseñador durante estas tareas cruciales del proceso creativo. La metodología empleada incluyó una exhaustiva búsqueda bibliográfica para comprender el desarrollo del diseño generativo en sus distintas etapas y campos de aplicación. Se identificaron los componentes principales que componen la estructura de objetos y se propuso una clasificación de estructuras básicas que abarca una amplia variedad de productos. Además, se estableció un flujo de trabajo que sirvió como guía para la implementación de la estructura básica, volúmenes, subestructuras y elementos adicionales. Los resultados destacan la implementación exitosa de un algoritmo en Rhino-Grasshopper, un lenguaje de programación visual, que permitió la generación de soluciones de diseño variadas para una diversidad de objetos. El diseño se enriqueció mediante componentes programados en Python, facilitando la implementación de subestructuras y elementos adicionales, tanto esenciales como no esenciales. En las conclusiones, se subraya la eficacia de la herramienta en la mejora del diseño generativo, atendiendo factores transversales como la estética, el aprovechamiento del uso del ordenador en la etapa temprana del diseño y la estabilidad de las soluciones propuestas. La contribución de esta investigación se refleja en la creación de una herramienta robusta y eficaz, aportando un nuevo enfoque en el ámbito de las herramientas de diseño en la etapa conceptual. Palabras clave: Diseño Generativo, herramientas CAD, diseño conceptual, estructuras básicas, soluciones de diseño. / [CA] En el transcurs de la present tesi doctoral, es va dur a terme la tasca d'analitzar el desenvolupament del disseny generatiu al llarg del temps i en diversos camps d'aplicació. Durant aquesta exploració, es va identificar una manca significativa d'eines *CAD de suport en l'etapa primerenca del disseny conceptual. L'absència de recursos per a facilitar la creació de dissenys conceptuals bàsics i la generació de diverses solucions de disseny es presenta com un problema evident en aquest context. L'objectiu principal de la investigació és desenvolupar una eina que aborde eficientment aquesta manca i proporcione assistència al dissenyador durant aquestes tasques crucials del procés creatiu. La metodologia emprada va incloure una exhaustiva cerca bibliogràfica per a comprendre el desenvolupament del disseny generatiu en les seues diferents etapes i camps d'aplicació. Es van identificar els components principals que componen l'estructura d'objectes i es va proposar una classificació d'estructures bàsiques que abasta una àmplia varietat de productes. A més, es va establir un flux de treball que va servir com a guia per a la implementació de l'estructura bàsica, volums, subestructures i elements addicionals. Els resultats destaquen la implementació reeixida d'un algorisme en *Rhino- *Grasshopper, un llenguatge de programació visual, que va permetre la generació de solucions de disseny variades per a una diversitat d'objectes. El disseny es va enriquir mitjançant components programats en *Python, facilitant la implementació de subestructures i elements addicionals, tant essencials com no essencials. A les conclusions, se subratlla l'eficàcia de l'eina en la millora del disseny generatiu, atenent factors transversals com l'estètica, l'aprofitament de l'ús de l'ordinador en l'etapa primerenca del disseny i l'estabilitat de les solucions proposades. La contribució d'aquesta investigació es reflecteix en la creació d'una eina robusta i eficaç, aportant un nou enfocament en l'àmbit de les eines de disseny en l'etapa conceptual. Paraules clau: Disseny Generatiu, eines CAD, disseny conceptual, estructures bàsiques, solucions de disseny. / [EN] In the course of this doctoral thesis, the task was undertaken to analyze the development of generative design over time and in various fields of application. During this exploration, a significant lack of CAD support tools in the early stage of conceptual design was identified. The absence of resources to facilitate the creation of basic conceptual designs and the generation of diverse design solutions presents itself as an evident problem in this context. The main objective of the research is to develop a tool that efficiently addresses this deficiency and provides assistance to the designer during these crucial tasks of the creative process. The methodology employed included a thorough literature review to understand the development of generative design in its different stages and fields of application. The main components composing the structure of objects were identified, and a classification of basic structures covering a wide variety of products was proposed. Additionally, a workflow was established as a guide for the implementation of the basic structure, volumes, substructures, and additional elements. The results highlight the successful implementation of an algorithm in Rhino-Grasshopper, a visual programming language, which allowed the generation of varied design solutions for a diversity of objects. The design was enriched through components programmed in Python, facilitating the implementation of both essential and non-essential substructures and elements. In the conclusions, the effectiveness of the tool in improving generative design is emphasized, addressing cross-cutting factors such as aesthetics, leveraging computer usage in the early stage of design, and the stability of the proposed solutions. The contribution of this research is reflected in the creation of a robust and effective tool, providing a new approach in the field of design tools in the conceptual stage. Keywords: Generative Design, CAD tools, conceptual design, basic structures, design solutions. / Acosta Zazueta, GR. (2024). Diseño generativo asistido por computador. Desarrollo de una herramienta innovadora de ayuda a la exploración de soluciones conceptuales en productos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203611
174

A Computational Platform For Automated Identification Of Building Blocks In Mechanical Design For Enhancing Ideation

Pal, Ujjwal 01 1900 (has links) (PDF)
Conceptual design is an early stage in the design process, in which functional requirements of a design problem are transformed into solution concepts for satisfying the requirements. It is regarded as a crucial step in design, because decisions made in this stage will strongly affect all the subsequent stages of the design process. Research evidence suggests that inspiration is useful for exploration and discovery of new solution spaces, and exploration of a wide variety of concepts increases the chances of developing more novel, and hence more creative solutions. There are various approaches to providing inspiration, e.g., creativity techniques such as trigger word technique, biomimetics such as Idea-Inspire, and computational synthesis approaches such as compositional synthesis. Computational synthesis tools are used for automated generation of concepts, which can be offered to the designer as triggers for inspiring ideation. The advantage of using solutions from computational synthesis as triggers are the following: the solutions can be produced in a relatively unbiased manner, allowing a variety of directions to be explored, and the solutions are exhaustive within the constraints of the databases or rules used, allowing a multitude of possibilities to be offered. However, computational synthesis has been traditionally used for automating solution generation, rather than creating triggers for designers’ ideation. Notwithstanding their potential for inspiring ideation, current computational synthesis approaches rarely focused on this task. One exception is FuncSION, a compositional synthesis tool, which can automatically synthesize solution concepts for mechanical devices, where a set of input and output characteristics i.e. functional requirements are provided by the user and the computer generates solutions by combining building blocks from a library to satisfy the requirements; these solutions are then used as stimuli for ideation by designers. The focus of this thesis is on evaluating and improving the effectiveness of computational synthesis in triggering ideation during conceptual design, in terms of improving the fluency and variety of the concept space produced. FuncSION has been used as the example synthesis approach on which the work has been focused. In order to evaluate the effectiveness of FuncSION in terms of fluency and variety, a method for assessing variety of a concept space is proposed, and a tool for supporting the assessment process has been developed. However, compositional synthesis research has always assumed that the building blocks are given, and has confined its focus on the process of combining the building blocks. It has not been investigated as to how such building blocks can be automatically identified. If new building blocks can be automatically identified, the resulting change in the library of building blocks would have a substantial effect on the outcomes of compositional synthesis, i.e. the triggers that can be offered to the designers for ideation, with a resulting effect on the concepts generated by the designers. Therefore, in this thesis, an automated method for building blocks synthesis has been proposed, and has been implemented as a computational tool.
175

Projeto conceitual e análise de desempenho do sistema de admissão de ar em uma aeronave não convencional de combate / Conceptual design and performance analysis of the air intake system in a non-conventional fighter aircraft

Bravo Mosquera, Pedro David 22 May 2017 (has links)
A concepção de aeronaves não convencionais a fim de alcançar um determinado desempenho ou melhoria operacional é sem dúvida um dos objetivos mais importantes da engenheira aeronáutica. Tais melhorias envolvem: redução de arrasto, redução da seção transversal, redução de ruído, redução da distância de decolagem e pouso, aumento da eficiência aerodinâmica, aumento da carga útil, entre outros. Por tanto, métodos de otimização multidisciplinar se tornaram em ferramentas muito úteis para aprimorar o projeto conceitual destas aeronaves. Neste contexto, este trabalho teve como objetivo o desenvolvimento do projeto conceitual de uma aeronave não convencional de combate e a análise de desempenho aerodinâmico do seu sistema de admissão de ar (Intake), tendo como principal característica, estar localizado na parte superior da fuselagem da aeronave (Dorsal Intake). O delineamento conceitual foi desenvolvido através da implementação de metodologias de otimização multidisciplinar de projeto (MDO) na fase de projeto paramétrico, integrando conceitos como: entropia estatística, desdobramento da função qualidade (QFD) e análise de restrições. Além disso, foram usados métodos analíticos e teóricos, ferramentas de desenho assistido por computador (CAD) e simulações da dinâmica dos fluidos computacionais (CFD) para otimizar e obter a configuração final da aeronave. Posteriormente, 5 configurações de asa delta foram selecionadas para avaliar as mudanças de desempenho do dorsal intake sob a influência aerodinâmica das superfícies principais da aeronave (Asa e Fuselagem), em regimes de voo subsônico (Mach = 0.4), transônico (Mach = 0.9) e supersônico (Mach = 1.7; 2) a diversos ângulos de ataque (De α = 10º a α = 30º ). Os resultados encontrados neste trabalho foram avaliados em separado, subsequentemente foram integrados, a fim de obter a nova concepção de aeronave não convencional de combate; a aplicação de MDO permitiu estimar as variáveis de projeto ideais para o desenvolvimento do projeto da aeronave, em relação a sua missão. Em contrapartida, os resultados da integração intake-estrutura mostram que apropriadas características de desempenho e compatibilidade foram mantidas durante as fases de voo subsônicas, para as 5 configurações de asa. No entanto, para velocidades transônicas, a configuração canard apresentou um acréscimo nos níveis de recuperação de pressão total, devido ao fluxo de alta energia na parte superior da fuselagem, o qual é produzido pelo vórtice do canard a moderados ângulos de ataque. Finalmente, para velocidades supersônicas, a asa com dispositivos LEX (Leading Edge Extensions) obteve os melhores níveis de recuperação de pressão total, pois a implementação destes dispositivos apresentou uma montagem mais vantajosa com sua fuselagem para gerar o cone de Mach, aumentando os níveis de recuperação de pressão total e reduzindo a distorção na face do motor. No entanto, para velocidades maiores a Mach = 2, sem importar a configuração de asa, a expansão do escoamento sobre a fuselagem e as asas da aeronave produziu um aumento no número Mach local na entrada do intake, o que reduziu os níveis de desempenho e compatibilidade do mesmo. Em consequência, a posição do intake na parte superior da fuselagem representa uma opção de configuração viável para aeronaves que requerem apenas capacidades de ângulo de ataque razoáveis, tais como aeronaves de caça ar-terra, sendo a asa com dispositivos LEX a geometria que representa melhores qualidades de desempenho na maioria dos 3 regimes de voo avaliados. / The conception of non-conventional aircraft with the aim of achieving a certain performance or operational improvement is undoubtedly, one of the most important objectives of the aeronautical engineering. These improvements involve: drag reduction, cross section reduction, noise reduction, shortening of take-off and landing distance, increase of aerodynamic efficiency, payload increase, among others. Therefore, optimization multidisciplinary methods became in very important tools to upgrade the conceptual design phase of these aircraft. In this context, this work had as aim the development of the conceptual design of a nonconventional fighter aircraft and the aerodynamic performance analysis of its air intake, having as main characteristic to be located at the top of the fuselage (Dorsal Intake). The conceptual design was developed through the implementation of multidisciplinary design optimization (MDO) methods in the parametric design phase, integrating concepts of: statistical entropy, quality function deployment (QFD) and constraint analysis. Besides that, it was used analytical and theoretical methods, computer-aided design (CAD) tools and computational fluid dynamics (CFD) simulations to optimize and obtain the final aircraft configuration. Subsequently, 5 delta wing configurations were selected to evaluate the dorsal intake performance changes under the aerodynamic influence of the main aircraft surfaces (Wings and Fuselage) in subsonic (Mach = 0.4), transonic (Mach = 0.9) and supersonic (Mach = 1.7; 2) flight regimes, at various angles of attack (From α = 10º to α = 30º ). The results found in this work were evaluated separately, later these were integrated, in order to get the new conception of non-conventional fighter aircraft; the MDO application allowed to estimate the ideal design variables for developing the aircraft design, regarding to its mission. On the other hand, the results of the intake-structure integration shown that appropriate performance and compatibility characteristics were maintained during the subsonic flight stages for the 5 wing configurations. However, for transonic velocities, the canard configuration presented an increase in the total pressure recovery levels, due to the high energy flux on the fuselage, which is produced by the canard vortex at moderate angles of attack. Finally, for supersonic velocities, the wing with LEX (Leading Edge Extensions) devices got the best levels of total pressure recovery, because the implementation of these devices presented a more advantageous assembly with its fuselage to generate the Mach cone, increasing the total pressure recovery levels and reducing the distortion at the engine face. However, for velocities higher than Mach = 2, regardless the wing configuration, the flow expansion on the fuselage and the wings produced an increase in the local Mach number in the intake entrance, which reduced the performance and compatibility levels of it. As a consequence, the top mounted intake position represents an option of viable configuration to aircraft that require only reasonable angles of attack capabilities, such as air-to-ground fighter aircraft, being the wing with LEX devices the geometry that represents better performance qualities in the majority of the 3 evaluated flight regimes.
176

Bayesian adaptive sampling for discrete design alternatives in conceptual design

Valenzuela-Del Rio, Jose Eugenio 13 January 2014 (has links)
The number of technology alternatives has lately grown to satisfy the increasingly demanding goals in modern engineering. These technology alternatives are handled in the design process as either concepts or categorical design inputs. Additionally, designers desire to bring into early design more and more accurate, but also computationally burdensome, simulation tools to obtain better performing initial designs that are more valuable in subsequent design stages. It constrains the computational budget to optimize the design space. These two factors unveil the need of a conceptual design methodology to use more efficiently sophisticated tools for engineering problems with several concept solutions and categorical design choices. Enhanced initial designs and discrete alternative selection are pursued. Advances in computational speed and the development of Bayesian adaptive sampling techniques have enabled the industry to move from the use of look-up tables and simplified models to complex physics-based tools in conceptual design. These techniques focus computational resources on promising design areas. Nevertheless, the vast majority of the work has been done on problems with continuous spaces, whereas concepts and categories are treated independently. However, observations show that engineering objectives experience similar topographical trends across many engineering alternatives. In order to address these challenges, two meta-models are developed. The first one borrows the Hamming distance and function space norms from machine learning and functional analysis, respectively. These distances allow defining categorical metrics that are used to build an unique probabilistic surrogate whose domain includes, not only continuous and integer variables, but also categorical ones. The second meta-model is based on a multi-fidelity approach that enhances a concept prediction with previous concept observations. These methodologies leverage similar trends seen from observations and make a better use of sample points increasing the quality of the output in the discrete alternative selection and initial designs for a given analysis budget. An extension of stochastic mixed-integer optimization techniques to include the categorical dimension is developed by adding appropriate generation, mutation, and crossover operators. The resulted stochastic algorithm is employed to adaptively sample mixed-integer-categorical design spaces. The proposed surrogates are compared against traditional independent methods for a set of canonical problems and a physics-based rotor-craft model on a screened design space. Next, adaptive sampling algorithms on the developed surrogates are applied to the same problems. These tests provide evidence of the merit of the proposed methodologies. Finally, a multi-objective rotor-craft design application is performed in a large domain space. This thesis provides several novel academic contributions. The first contribution is the development of new efficient surrogates for systems with categorical design choices. Secondly, an adaptive sampling algorithm is proposed for systems with mixed-integer-categorical design spaces. Finally, previously sampled concepts can be brought to construct efficient surrogates of novel concepts. With engineering judgment, design community could apply these contributions to discrete alternative selection and initial design assessment when similar topographical trends are observed across different categories and/or concepts. Also, it could be crucial to overcome the current cost of carrying a set of concepts and wider design spaces in the categorical dimension forward into preliminary design.
177

A portfolio approach to design in the presence of scenario-based uncertainty

Cooksey, Kenneth Daniel 20 September 2013 (has links)
Current aircraft conceptual design practices result in the selection of a single (hopefully) Pareto optimal design to be carried forward into preliminary design. This paradigm is based on the assumption that carrying a significant number of concepts forward is too costly and thus early down-selection between competing concepts is necessary. However, this approach requires that key architectural design decisions which drive performance and market success are fixed very early in the design process, sometimes years before the aircraft actually goes to market. In the presence of uncertainty, if the design performance is examined for individual scenarios as opposed to measuring performance of the design with aggregate statistics, the author finds that the single concept approach can lead to less than desirable design outcomes. This thesis proposes an alternate conceptual design paradigm which leverages principles from economics (specifically the Nobel prize-winning modern portfolio theory) to improve design outcomes by intelligently selecting a small well diversified portfolio of concepts to carry forward through preliminary design, thus reducing the risk from external events that are outside of the engineer’s control. This alternate paradigm is expected to result in an increase in the overall profit by increasing the probability that the final design matches market needs at the time it goes to market. This thesis presents a portfolio based design approach, which leverages dynamic programming to enable a stochastic optimization of alternative portfolios of concepts. This optimization returns an optimized portfolio of concepts which are iteratively pruned to improve design outcomes in the presence of scenario-driven uncertainties. While dynamic programming is identified as a means for doing a stochastic portfolio optimization, dynamic programming is an analytical optimization process which suffers heavily from the curse of dimensionality. As a result, a new hybrid stochastic optimization process called the Evolutionary Cooperative Optimization with Simultaneous Independent Sub-optimization (ECOSIS) has been introduced. The ECOSIS algorithm leverages a co-evolutionary algorithm to optimize a multifaceted problem under uncertainty. ECOSIS allows for a stochastic portfolio optimization including the desired benefit-to-cost tradeoff for a well-diversified portfolio at the size and scope required for use in design problems. To demonstrate the applicability and value of a portfolio based design approach, an example application of the approach to the selection of a new 300 passenger aircraft is presented.
178

Metodologia de disseny conceptual d'estacions depuradores d'aigües residuals que combina el procés de decisió jeràrquic amb l'anàlisi de decisions multicriteri

Vidal Roberto, Núria 12 March 2004 (has links)
La present tesi proposa una metodologia de disseny conceptual d'estacions depuradores d'aigües residuals (EDAR) mitjançant la combinació del procés de decisió jeràrquic i l'anàlisi de decisions multicriteri. El document s'inicia amb una breu introducció als principals camps abordats pel treball: el disseny dels processos químics en general, el disseny de les estacions depuradores d'aigües residuals en particular, i l'anàlisi de decisions multicriteri aplicada a la gestió ambiental. Seguidament, es fixen els objectius del treball i es descriuen tant la metodologia com el material de suport informàtic utilitzats. Per validar i contrastar la metodologia de disseny presentada, es desenvolupa un cas d'estudi on es porta a terme el disseny conceptual d'una EDAR que presenta els mateixos requeriments que l'EDAR que opera actualment al municipi de Granollers. Inicialment es presenta la informació de partida i tot seguit es defineixen els objectius de disseny, així com el conjunt de criteris que s'utilitzaran per avaluar en quina mesura es compleixen aquests objectius. Els objectius de disseny són de diferents tipus: ambientals, tècnics, socials i econòmics, i el conjunt de criteris utilitzats, concretament 33, també es classifica segons aquestes quatre categories. Cadascun dels criteris presenta un determinat pes d'importància relativa en la presa de decisions. Finalment, es desenvolupa tot el procés de decisió fins a obtenir el disseny complet de l'EDAR. El procés de decisió s'ha dividit en dues parts diferenciades però que alhora s'entrellacen: la línia d'aigua i la línia de fang. El procés de decisió presenta un total de divuit qüestions amb un màxim de quatre alternatives per pregunta (dotze qüestions corresponen a la línia d'aigua, i sis a la línia de fangs). Per solucionar cadascuna d'aquestes qüestions, s'avaluen les alternatives proposades respecte a un conjunt de criteris triats de la llista inicial. Aplicant el procés de decisió multicriteri anomenat SMART (simple multiattribute rating technique), es combinen els resultats de les alternatives respecte a cada criteri, tenint en compte la importància de cada criteri per obtenir un sol valor per alternativa. Per quantificar els criteris referents a l'operació del procés i les de tipus econòmic s'han utilitzat els programes GPS-X i CapdetWorks respectivament. Pel que fa als criteris no quantificats mitjançant aquests programes, s'han resolt de manera qualitativa i mitjançant manuals de disseny i també tenint en compte l'opinió d'experts en aquest camp. L'alternativa que obté un pes més elevat és la recomanada per al procés de decisió. El cas d'estudi finalitza un cop s'obté el disseny complet de l'EDAR. Per integrar tots aquests elements que hem esmentat i donar suport al desenvolupament del procés de decisió s'ha utilitzat el programa DRAMA (Design Rationale Management). A continuació, es fa una anàlisi comparativa entre l'EDAR que hi ha actualment al municipi de Granollers i l'EDAR resultat del cas d'estudi. Es descriu el diagrama de flux que conforma l'EDAR de Granollers i el diagrama de flux de l'EDAR resultat de l'estudi, se'n fa una anàlisi comparativa justificant cadascuna de les decisions preses en el cas d'estudi i, finalment, es fa una discussió de resultats on es reflecteixen els avantatges associats d'aplicar la metodologia de disseny conceptual proposada. Finalment, es presenten les conclusions de la tesi. Els principals resultats de la tesi es van publicar el 2002 a la revista internacional Industrial and Engineering Chemistry Research (N. Vidal, R. Bañares-Alcántara, I. Rodríguez-Roda i M. Poch: "Design of wastewater treatment plants using a conceptual design methodology", Industrial and Engineering Chemistry Research, 41 (20), pàg. 4993-5005) i la continuació de la línia de recerca al Laboratori d'Enginyeria Química i Ambiental de la UdG ha comportat la presentació del treball de recerca de Xavi Flores "Procés de decisió jeràrquic combinat amb anàlisi multicriteri per al suport al disseny conceptual de sistemes de fangs actius d'una estació depuradora d'aigües residuals" i la presentació dels resultats parcials al congrés internacional de la 9th IWA Conference on Design, Operation and Economics of Large Wastewater Treatment, que va tenir lloc el setembre passat a Praga ("Combining hierarchical decision process with multi-criteria analysis for conceptual design of WWTP", X. Flores, N. Vidal, A. Bonmatí, J. B. Copp i I. Rodríguez-Roda). / This thesis proposes a methodology for the conceptual design of wastewater treatment plants (WWTP) via a combination of a hierarchical decision process and multicriteria decision analysis. We begin with a brief introduction into the main fields of study involved in this work: the design of chemical processes in general; the design of wastewater treatment plants in particular and multicriteria decision analysis as applied to environmental management. We go on to outline the objectives of the study and then describe our methodology as well as the computer-based support tools used. In order to evaluate and contrast our design methodology, we present a study case in which a conceptual design is developed for a WWTP which has the same requirements as the actual WWTP currently in operation in the town of Granollers. First, we present the initial information and then define the design objectives, as well as the set of criteria that will be used in order to evaluate the degree to which the objectives have been met.The design objectives are of different types: environmental, technical, social and economical; the set of criteria, of which there are 33 in all, are also classified into these four categories. Each of the criteria has a specific weighting in terms of their importance in taking decisions. Next, we go through the whole decision process leading to the completion of the design of the WWTP. The decision process has been divided into two parts which are differentiated but at the same time, interconnected: the water line and the sludge line. The decision process involves a total of eighteen questions (twelve for the water line and six for the sludge line) with a maximum of four alternatives per question. In order to answer each question, the proposed alternatives are evaluated in relation to a set of criteria chosen from the initial list. Applying the multicriteria decision process known as SMART (simple multiattribute rating technique), the results for the alternatives with respect to each criteria are combined, bearing in mind the importance of each criteria, in order to get a single value for each alternative. To get the results for those alternatives relating to the operation of the process and those to do with economical factors, we used the GPS-X and CapdetWorks programmes, respectively. The criteria not quantified by means of these programmes were resolved by qualitative means and through the use of design manuals, in addition to taking expert opinion into account. The alternative that obtains the highest weighting is the one which is recommended by the decision process. The study case is completed once a complete design of the WWTP is obtained. In order to integrate all the elements we have mentioned, and to assist the development of the decision process, we employed the programme known as DRAMA (Design Rationale Management). We then go on to give a comparative analysis between the real WWTP in Granollers and the WWTP resulting from our study case. We describe and compare the flow diagrams in both cases, providing justification for each of the decisions taken in the study case and then discuss the results, reflecting on the advantages to be gained from using the methodology of conceptual design we propose. Finally, we present the conclusions of our thesis.The main results of this thesis were published, in 2002, in the international magazine, Industrial and Engineering Chemistry Research (N. Vidal, R. Bañares-Alcántara, I. Rodríguez-Roda and M. Poch: "Design of wastewater treatment plants using a conceptual design methodology", Industrial and Engineering Chemistry Research, 41 (20), pages 4993-5005). Continuing work in this line of research at the Laboratori d'Enginyeria Química i Ambiental at the University of Girona has led to the research work by Xavi Flores, Procés de decisió jeràrquic combinat amb anàlisi multicriteri per al suport al disseny conceptual de sistemes de fangs actius d'una estació depuradora d'aigües residuals (A hierarchical decision process combined with multicriteria analysis to assist conceptual design of active sludge systems in a wastewater treatment plant) and the presentation of the preliminary results at the 9th IWA Conference on Design, Operation and Economics of Large Wastewater Treatment, which took place in September, 2003, in Prague ("Combining hierarchical decision process with multi-criteria analysis for conceptual design of WWTP", X. Flores, Núria Vidal, August Bonmatí, J. B. Copp and Ignasi Rodríguez-Roda).
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Collaborative framework in computer aided innovation 2.0 : Application to process system engineering / Plateforme collaborative d’innovation ouverte assistée par ordinateur : Application en génie des procédés

Lopez Flores, René 05 October 2015 (has links)
L'innovation est un processus complexe qui demande des techniques et des outils collaboratifs pour la gestion des connaissances et la communication, afin que les entreprises surmontent les défis d'une économie concurrentielle. Une nouvelle catégorie d’outils connus sous l’acronyme CAI (Computer Aided Innovation) émerge parmi l’éventail des technologies assistées par ordinateur afin de répondre aux demandes industrielles pour une plus grande fiabilité des nouveaux produits et procédés. L’objectif de ces outils (en cours de développement) est d’aider les concepteurs durant tout le processus d’innovation. Actuellement la mise en oeuvre d’un tel outil doit prendre en considération deux développements récents majeurs. Le premier est d’ordre technologique avec les possibilités offertes par le Web 2.0 dans le développement de logiciel. Le deuxième est plus stratégique avec un changement de vision de l’innovation passant de l’innovation fermée (interne à l’entreprise) à l’innovation ouverte (Open Innovation). Ces deux aspects conduisent à de nouvelles formes de CAI nommé Open CAI 2.0. Cette recherche propose une des briques d’un tel outil, pour assister les ingénieurs procédés à résoudre des problèmes innovants principalement dans la phase de conception préliminaire. Nous présentons la structure et la fonctionnalité d’un cadre de collaboration qui met en oeuvre une méthode développée basée sur le couplage entre la théorie TRIZ, et une technique de gestion des connaissances: le raisonnement à partir de cas (RàPC). Ce cadre est une extension du modèle TRIZ-RàPC validé dans le domaine du génie de procèdes. L’approche du processus de résolution est illustrée sur une étude de cas traitant de la gazéification de la biomasse. / In economy nowadays, the act of innovation is in general social; it requires the management of knowledge, and the techniques and methodologies to drive it. Innovation is not the product of one isolated intelligence, instead, it is the result of a multi-disciplinary workgroup lead by a process or a methodology. The conceptual design, which is found in the first stages of the innovation process, represents one of the most important challenges in industry nowadays. One of the main challenges faced by chemical industries related to the conceptual design phase is to provide the means in the form of methods and computational tools, for solving problems systematically, at the same time that benefiting from the collective efforts of individual intelligences involved. Hence, the main objective of this work is to provide a solution to improve the creative capacity of a team involved in the innovation process, in particular the preliminary (critical) phase of conceptual design. Consequently, it is important to understand the techniques, methods and tools that best support the generation of novel ideas and creative solutions. In addition, it is necessary to study the contribution of information and communication technologies as the mean to support collaboration. Web technologies are considered as complementary tools to implement methods and techniques in collaborative design, and particularly in the conceptual design stage. These technologies allow setting up distributed collaborative environments to bring together the resources and the experts who can relate the existing pieces of knowledge to new contexts. It is the synergy created in this kind of environment, which allow producing valuable concepts and ideas in the form of Collective Intelligence. Nevertheless in most existing solutions for collective intelligence or crowdsourcing environments, they do not report the use of a particular methodology to improve the participants' creativity. The solution in this work describes a social network service that enables users to cooperatively solve problems oriented (but not limited) to the phase of conceptual design. In this work we propose that the use of Collective Intelligence in combination with the model TRIZ-CBR could lead the creative efforts in a team to develop innovative solutions. With this work we are looking for connecting experts from one particular field, TRIZ practitioners and stakeholders with the objective to solve problems in collaboration unlashing the collective intelligence to improve creativity. This work uses the basis of the concept named "Open CAI 2.0" to propose a solution in the form of a theoretical framework. The contributions seek to move the development of the field in Computer Aided Innovation a step forward.
180

Método de avaliação ambiental de conceitos de produtos baseado nas estratégias do DFE e no AHP

Ruy, Marcelo 26 September 2011 (has links)
Made available in DSpace on 2016-06-02T19:50:12Z (GMT). No. of bitstreams: 1 3913.pdf: 2990880 bytes, checksum: 4d26eae63ccca4196bc018988c087ba9 (MD5) Previous issue date: 2011-09-26 / The objective of the present thesis is to propose and structure a method for environmental evaluation of products concepts based on DfE Strategies and AHP. The focus is on physical products, mainly consumer durable goods and capital goods. The justification for this choice is that sustainability is a big issue today, and in particular: the urgency of approaching environmental problems; its strong relationship with product development; and the need of methods and tools for addressing environmental issues at the initial phases of product design, more specifically methods for environmental evaluation of product concepts, due to its scarcity in the literature. This objective was reached in two stages. Initially, the method was structured in phases, stages and activities arranged in an orderly manner. The method was built from DfE strategies related to the product physical dimensions and expressed by the use and consumption of material resources. DfE Strategies was condensed in evaluation criteria. These criteria was subsequently related to a products environmental typology and further grouped by degree of similarity, forming a hierarchy of environmental criteria to be used with AHP. Thus, we sought to create a method applicable to a wide range of physical products and whose aim is to guide the user, step by step, in the evaluation of the concept that better fulfills DfE criteria, taking the whole life cycle of the product into account. In the second stage, the practical utility potential of the method was assessed by means of interviews and questionnaires with product development practitioners from three companies and with one DfE consultant. As a result, it was concluded that the proposed method constitutes in a contribution to the development of environmental responsible products. / Este trabalho tem como objetivo conceber e estruturar um método de avaliação ambiental de conceitos de produtos baseado nas Estratégias do DfE e no AHP, com foco nos produtos físicos, principalmente os bens de consumo duráveis e os bens de capital. A justificativa por esta escolha se deve à atualidade da temática da sustentabilidade e, em particular: à premência do tratamento da questão ambiental; sua forte dependência do processo de desenvolvimento de produtos; e à necessidade de métodos e ferramentas apropriados para se incorporar as questões ambientais nas fases iniciais do projeto do produto, mais especificamente métodos adequados à avaliação ambiental de conceitos de produtos, devido a sua escassez na literatura. Este objetivo foi alcançado por meio de duas etapas. Inicialmente, o método foi estruturado em fases, etapas e atividades, todas dispostas em uma ordem lógica. O método foi construído a partir de estratégias de DfE relacionadas à dimensão física do produto e expressas pelo uso e consumo de recursos materiais. As estratégias de DfE foram condensadas em critérios de avaliação. Tais critérios foram posteriormente relacionados com uma tipologia ambiental de produtos e depois agrupados por grau de semelhança, formando uma hierarquia de critérios ambientais para uso com o AHP. Desta maneira, buscou-se criar um método aplicável a uma gama de produtos físicos, cujo objetivo é orientar o usuário, passo a passo, na avaliação do conceito que mais bem atenda aos critérios do DfE, dentro de uma perspectiva de ciclo de vida do produto. A segunda etapa da pesquisa consistiu na avaliação do potencial de utilização prática do método por meio de entrevistas e questionários com profissionais ligados ao desenvolvimento de produtos de três empresas e com um consultor em DfE. Como resultado concluiu-se que o método proposto se constitui em uma contribuição para o desenvolvimento de produtos ambientalmente responsáveis.

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