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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.
31

Spelbranschens designprocesser : Teori vs verklighet / Game industry´s design processes : Theory vs reality

Nilsson, Jacob, Phan, Boimy January 2015 (has links)
The game industry is a fast growing market. What have been seen recently are a high turnovers and a rapid increase of both game companies and their employees. The game market is developing and the game companies are trying to keep up with the market. Both when it comes to the development of games and also to reach new levels in the design process. The design process is unique and the game companies have different ways to develop their products. The methods are different depending on the game company but the basic foundation is to use support in the development process of the product. The question we ask ourselves is: How do game companies proceed in their design process when the surroundings are changing at a rapid pace? This thesis aim to find out how the deigns process function in the Swedish game industry. Focus will be on today´s design process but also on how the development is preceded. Through a quantitative interview and a qualitative survey we analyses the current situation of today‟s Swedish game companies in terms of the design processes. The result shows that all the respondents use their design process with a combination of their own methods and previous research. How to create an idea differs depending on the game companies. The implementation of the idea may vary and some of the methods are retained when they are considered important. The market also has a certain influence of how a design process should be performed. The customers have become more knowledgeable and have higher demands on how the game should perform. Therefore, the gaming companies need to adapt to the market development in order to achieve their success. / Spelbranschen är en bransch som expanderar snabbt med hög omsättning och en snabb ökning av spelföretag och anställda. I och med att spelbranschen och spelutvecklingen går framåt i en hög takt försöker spelföretag hålla samma takt med spelutvecklingen för att nå nya framsteg och utveckling i sina designprocesser. I en designprocess har spelföretag olika tillvägagångssätt för att utveckla sina spelprodukter. Tillvägagångssätt kan se olika ut beroende på vilket spelföretag man arbetar för, men den grundläggande tanken är att använda dem som hjälpmedel vid utvecklingen av en spelprodukt. Men hur går spelföretag tillväga med sina designprocesser när omgivningen förändras i en rask takt? Vårt examensarbete går ut på att undersöka hur en designprocess ser ut i dagsläget av den svenska spelbranschen och hur de går tillväga. Genom en kvalitativ intervju och en kvalitativ enkät har vi fått en bild av hur det ser ut för dagens svenska spelföretag när det gäller deras designprocesser. Resultatet visar att samtliga respondenter som vi har fått in, utför sin designprocess med en kombination av sina tillvägagångssätt med tidigare forskning. Idéskapande kan vara olika från olika spelföretag, genomförande av idé kan variera, men en del av metoder behålls då de anses vara viktiga. Marknaden har även en viss påverka på hur en designprocess utförs. Kunderna bli mer kunnig och har höga krav på hur spelet ska se ut, därför måste spelföretagen anpassa sig efter marknadens utveckling för att kunna nå sina framgångar.
32

Bemessungsmodell zur Berechnung der Tragfähigkeit von biegeverstärkten Stahlbetonplatten

Frenzel, Michael, Curbach, Manfred 05 December 2011 (has links) (PDF)
In diesem Beitrag werden ein Berechnungsverfahren und ein Bemessungskonzept für biegebeanspruchte textilbetonverstärkte Stahlbetonbauteile vorgestellt. Ihre Anwendbarkeit wird durch die Auswertung von Versuchen an verstärkten Stahlbetonplatten mit einer Reihe veränderlicher Ausgangswerte überprüft. Als Ergebnis dieser Arbeit stehen dem Anwender einfach nutzbare, praxisgerechte Bemessungstabellen zur Verfügung. / This article introduces a calculation method and a design concept for reinforced concrete elements strengthened with textile concrete. Its applicability is verified by an analysis of tests with strengthened steel reinforced concrete slabs with a certain variety of design parameters. Results of this work are easy manageable, praxis-orientated design tables that are available for users.
33

MDA Approach in Real-Time Systems Development with Ada 2005

Gruszka, Robert January 2007 (has links)
Over the years, number of design methodologies were developed. One of the state-of-the-art modeling approaches is Model Driven Architecture. This thesis is an attempt to utilize the MDA in a specific and complex domain – real-time systems development. In MDA framework there are three levels of abstraction: computation independent, platform independent and platform specific. The target environment of the method presented in the thesis is Ada 2005 programming language which extended the old version of the language with several new object-oriented features making it suitable for using with the MDA. Application of the MDA in real-time systems domain targeted towards Ada 2005 implementation constitutes a new design method which benefits from the MDA, UML and Ada 2005 advantages. The thesis starts with presentation of the complexity of the real-time systems domain. A few real-time domain aspects are chosen as a main area for elaborating the design method. The utilizes UML Profile for Schedulability, Performance and Time for defining platform independent model. Additionally it provides its extension – the Ada UML profile – which constitutes the platform specific model. This is followed by specification of transformations between platform independent and specific model. The specification is used as a base for implementation of the transformations. Guidelines for code generation form the Ada UML profile are also provided. Finally, the thesis describes how the transformations can be implemented in Telelogic TAU tool. / gruszka.robert@gmail.com
34

Contribution à la formalisation des liens invention-optimisation en conception inventive / Contribution of the formulation of the links between Invention - Optimization in Inventive conceptual design

Chinkatham, Thongchai 13 January 2016 (has links)
Une des caractéristiques les plus frappantes de la conception inventive est le fait qu’évaluer des solutions peut se révéler être plus difficile que de les trouver. Avoir des idées est inutile si celles-ci sont rejetées à un stade précoce. Dans de nombreuses évaluations qualitatives et méthodes sélectives, les critères d’évaluation sont généralement constitués à partir des besoins de conception qui sont fortement influencé par les préférences ou l’expérience des décideurs. Afin de tirer parti de l’inventivité d’une entreprise en octroyant des chances supplémentaires quant à des concepts possibles, cette thèse présente des approches et des outils d’aide à l’évaluation et à la sélection de concepts de solution obtenus dans le cadre de la Méthode de Conception Inventive. Les contributions de cette thèse peuvent servir comme outils d’aide à la conception et à la prise de décision. / One of the most striking characteristics of inventive design is that evaluating solutions may prove to be more difficult than finding them. Having good ideas is useless if they are rejected at an early stage. In many existing qualitative evaluation and selection methods (see design model), evaluation criteria are usually taken from the design requirement, which is strongly influenced by customer preferences or decision makers’ experience. In order to leverage inventiveness of a company through additional chances of feasible concepts. This thesis presents approaches and support tools to evaluate and select Solution Concepts obtained from Inventive Design Method (IDM) framework. The contributions in this thesis can be used as a decision-making aid and tool.
35

Système de fondation sur pieux bois : une technique millénaire pour demain / System of timber pile foundation : an old technique for today

Christin, Jérôme 09 September 2013 (has links)
La France possède un patrimoine très riche d'ouvrages d'art et de bâtiments fondés sur des pieux en bois. Les ponts construits sur la Loire, sur la Seine, le château de Chambord ou encore le Grand Palais à Paris en sont quelques exemples. Cependant, malgré un parc français important d'ouvrages bâtis sur des pieux en bois, le retour d'expérience sur la portance résiduelle et l'état de dégradation de leurs fondations est faible et non capitalisé. Les principaux objectifs de ce travail, qui s'intègre dans le projet Pieux Bois, sont d'une part, de définir une méthodologie d'analyse des fondations en bois des ouvrages visant à évaluer leur état de dégradation, et d'autre part, de proposer une méthode de dimensionnement des pieux en bois s'appuyant sur les caractéristiques pressiométriques des terrains. L'état de l'art réalisé dans le cadre de ce projet a permis d'identifier une centaine de ponts français construits sur des pieux en bois entre le Moyen-Âge et l'époque industrielle, principalement situés dans le lit des fleuves et de leurs affluents. Les désordres relevés sur ces ouvrages ainsi que les solutions de confortement mises en œuvre pour assurer leur pérennité ont été établis. La méthodologie d'analyse présentée dans un guide d'inspection des fondations en bois élaboré aux Pays-Bas a été validée lors de l'évaluation de l'état de dégradation des pieux de fondation d'un viaduc ferroviaire situé à proximité de Bordeaux. Les propriétés mécaniques de l'interface entre le sol (limon) et le bois ont été étudiées à partir d'une campagne d'essais en laboratoire à la boîte de cisaillement direct. Des essais de cisaillement d'interface avec le mortier et l'acier ont également été réalisés. L'influence de la rugosité des matériaux et de la teneur en eau du limon sur les propriétés de résistance d'interface a été examinée. Les essais de cisaillement en laboratoire ont été complétés par la réalisation de deux plots expérimentaux sur lesquels des pieux en bois ont été battus et chargés en compression. Les pieux ont été préalablement munis d'un système d'instrumentation accueillant un chapelet d'extensomètres amovibles. Les résultats de ces essais de chargement ont été intégrés dans une base de données d'essais de pieux en bois construite à partir de données publiées dans la littérature. La démarche mise en œuvre pour établir les règles pressiométriques présentées dans la nouvelle norme d'application nationale de l'Eurocode 7 a été reprise et modifiée. Les études statistiques menées à partir de cette base de données ont permis de proposer un modèle de calcul des résistances de pointe et de frottement des pieux en bois battus dans les argiles limons et les sables graves / Many buildings and bridges built on timber pile foundations still stand in France. The bridges on rivers “Loire” and “Seine”, the castle of Chambord, the “Grand Palais” in Paris are a few examples of French monuments founded on timber piles. However, despite a large number of buildings and bridges constructed in France, the feedback on the residual bearing capacity and the degradation of timber piles is scarce. The main objectives of this work, which is part of the “Pieux Bois” national research project, are, on the one hand, to define a methodology in order to analyze timber pile foundations degradation, and on the other hand, to propose a design method of timber piles based on the results obtained from pressuremeter tests. The state of the art made in the national project identified about one hundred French bridges built on timber piles between the Middle Ages and the industrial era. They are mainly located in basins of rivers. Pathologies were observed on bridges and reinforcement solutions were implemented in order to avoid any future problems. The methodology for the inspection of timber pile foundations given in the Dutch guide was applied to investigate the degradation of timber piles under an existing railway bridge near Bordeaux. Series of laboratory tests were carried out on soil (silt) and wood with a direct shear box. The mechanical properties of the interface were studied. Shear tests between mortar, steel and silt were also carried out. The influence of material roughness and silt moisture content on the shear strength properties of the interface was examined. In addition, timber piles were driven and loaded on two experimental sites. The timber piles were instrumented with removable extensometers. The results of these load tests were included in a database which contained timber piles loading test results published in literature. The approach adopted to establish the design method of deep foundation based on the results obtained from pressuremeter tests described in the new national standard for application of Eurocode 7 was modified. A new model of calculation of timber piles shaft and base resistance driven in clay silt and sand gravels was determined with statistical studies from this database
36

Design and integration of multi-disciplinary interfaces : method and modelling language for mechatronic systems engineering / Conception et intégration d’interfaces multi-disciplinaires : méthode et modélisation pour l’ingénierie des systèmes mécatroniques

Zheng, Chen 14 December 2015 (has links)
Les systèmes mécatroniques sont caractérisés par la combinaison synergique de la mécanique, de l'électronique et de l'informatique en temps réel. Ils possèdent leur propre cycle de vie et doivent associer des expertises métiers et des technologies très variées, ce qui rend leur conception plus complexe et nécessairement plus intégrée. Afin de mettre en œuvre une approche permettant d’assurer une meilleure intégration fonctionnelle et spatiale des systèmes mécatroniques, et plus particulièrement sur l’axe développement de produit en assurant une meilleure combinaison des expertises métier, deux types de problématiques doivent être surmontés. La première problématique a trait aux données de conception alors que la seconde est relative aux processus. La contribution de nos travaux de thèse s’appuie sur deux concepts complémentaires. Le premier, un modèle d’interfaces multidisciplinaires, est proposé pour répondre à la problématique relative aux données de conception. Ces interfaces s’appuient sur l’architecture du système et précisent quels transferts existent entre les composants conçus par les différentes disciplines. Instanciées dans le modèle de données, les interfaces multidisciplinaires permettent d’échanger et de partager les informations entre les différentes disciplines. Le second concept concerne la méthode de conception basée sur le modèle d’interfaces multidisciplinaires. Cette méthode est définie pour pouvoir établir le processus d’ingénierie et permettre une meilleure intégration des expertises métiers tout au long de la conception des systèmes mécatroniques. Enfin, les deux propositions sont implémentées par l’intermédiaire d’un démonstrateur basé sur 3DEXPERIENCE Platform. Un système de mesure 3D, combinaison synergique de la mécanique, de l'électronique, de l'informatique et l’optique, est utilisé afin de démontrer et de valider les contributions par nos travaux en termes d'intégration multidisciplinaire des expertises métier lors de la conception des systèmes mécatroniques. / Mechatronic system is considered as a synergetic combination of mechanical engineering, electronic engineering and computer engineering. Such mechatronic system has its own lifecycle and should integrate different disciplines and various technologies. Therefore the design of mechatronic systems becomes increasing complex. In order to propose an approach to achieve a better functional and spatial integration of mechatronic systems, especially to achieve a higher integration of different disciplines during the design process of mechatronic systems, two kinds of problems must be overcome. The first problem is related to design data of mechatronic systems while the second is related to the design process. The contribution of the thesis is based on two complementary concepts. The first contribution, the multi-disciplinary interface model, is proposed to address the issue of design data. These interfaces are based on the system architecture and specify which transfers exist between components designed by the project teams of different disciplines. Instantiated in the data model, multi-disciplinary interfaces enables a better data exchange and sharing among the engineers of different disciplines. The second concept concerns the design method based on the multi-disciplinary interface model. This method is proposed to establish the process for mechatronic engineering in order to achieve a better multi-disciplinary integration for the design of mechatronic systems. Finally, the two propositions are then implemented in a demonstrator developed based on 3DEXPERIENCE Platform. A 3D measurement system, considered as a synergistic combination of mechanical engineering, electronic engineering, computer engineering and optical engineering, is used to demonstrate and validate the propositions of the thesis in terms of multi-disciplinary integration for the design of mechatronic systems.
37

Proposition d'un processus d'évaluation multidomaine pour améliorer la conception de produit / Proposal for a multidomain evaluation process to improve product design

Audoux, Kévin 02 July 2019 (has links)
La concurrence industrielle pousse les entreprises à développer de nouveaux produits innovants. En outre, les industriels sont soumis à de plus en plus de contraintes issues des différents acteurs du processus de conception (fabricants, utilisateurs) ou liées aux évolutions de leur environnement (réglementations, technologies). Il leur est donc nécessaire d’adapter leurs activités de conception et plus particulièrement les étapes d’évaluation pour que les produits développés correspondent aux exigences multiples de toutes les parties prenantes. Ces contraintes se traduisent par l’intégration de nouveaux domaines ou l’évolution de domaines existants dans le processus de conception.Dans ce contexte, l’objectif de ces travaux de thèse est de formaliser et d’apporter des méthodes permettant l’évaluation multidomaine dans le processus de conception. Ce manuscrit s’intéresse donc à la problématique suivante : « Comment les phases d’évaluation dans un processus de conception multidomaine peuvent-elles permettre d’accroître les performances du produit à partir des représentations intermédiaires ? ». Pour cela nous proposons une méthodologie permettant d’améliorer le processus d’évaluation en créant un outil d’évaluation multidomaine et en formalisant les étapes du processus d’évaluation pour apporter des méthodes d’amélioration adaptées aux domaines concernés par le produit à concevoir. Des expérimentations sont menées afin de valider leurs apports dans le processus de conception en s’intéressant notamment à trois domaines : l’innovation, la prise en compte des impacts environnementaux et la fabrication additive. Ces expérimentations ont permis de valider la méthodologie de création de l’outil d’évaluation et l’apport des étapes d’amélioration. / Industrial competition is driving companies to develop new innovative products. In addition, industrial companies are increasingly subject to constraints from the various actors in the design process (manufacturers, users) or linked to changes in their environment (regulations, technologies). It is therefore necessary for them to adapt their design activities and more particularly the evaluation steps so that the products developed correspond to the multiple requirements of all stakeholders. These constraints result in the integration of new domains or the evolution of existing domains into the design process.In this context, the objective of this thesis work is to formalize and provide methods for multidomain evaluation in the design process. This manuscript therefore addresses the following question: "How can evaluation phases in a multidomain design process help to increase the performance of intermediate representations? ». To this end, we propose a methodology to improve the evaluation process by creating a multidomain evaluation tool and formalizing the steps of the evaluation process to provide improvement methods adapted to the areas concerned by the product to be designed. Experiments are being carried out to validate their contribution to the design process, focusing in particular on three areas: innovation, taking into account environmental impacts and additive manufacturing. These experiments made it possible to validate the methodology for creating an evaluation tool and the contribution of the improvement steps.
38

Soil Steel Composite Bridges. An international survey of full scale tests and comparison with the Pettersson-Sundquist design method

Moreo Mir, Alberto January 2013 (has links)
Nowadays, many different efficient solutions are being studied to solve engineering problems. Inside this group of solutions we can find the Soil Steel Composite Bridges (SSCB) as an alternative to traditional bridges. SSCB are being used more often every day and they are showing themselves as competitive structures in terms of feasibility and constructability. This project was started to achieve two different goals. The first one was to create a general database of SSCB including few selected tests all around the world and the second one was to compare and discuss full scale tests using the Pettersson-Sundquist design method. To create the database and the following comparisons, twenty-five different full scale tests were used. From this tests all the necessary information was extracted and used to create the database. After creating the database, the project continued with the discussion and comparison of the full scale tests. Specifically those discussions and comparisons were related to the resistance of the soil (the soil modulus) used in the construction of the SSCB. All the values of the different soil modulus of each full scale test used in the comparisons were calculated using the Swedish Design Manual (SDM). Two different types of soil modulus were calculated in this project using SDM, ones are the soil modulus back calculated using the values reported from the live load tests performed on the culverts and the others are theoretical soil modulus calculated using the detailed information of the soil. The report continues with the explanation of the different conclusions ended up with during this project. It can be highlighted within this group of conclusions, the one related to the importance of reporting all the necessary information from the full scale tests including the soil parameters, the measures of the culvert, the cross sectional parameters and the vehicle dimensions among others. Another important conclusions are the effect of using the slabs over the top of the culvert and how it would effect to the sectional forces over the culvert and also the limitations using method B of the SDM regarding the type of soil used as backfilling Finally, the project finishes explaining some proposals for future research about other fields of the study of SSCB.
39

The Speed-Track

Dongue Dongue, Dietrich Kevin, Grosso, Lorenzo January 2013 (has links)
The Speed-Track is a prototype of tracked vehicle made for material transportation on yards andgalleries. It was realized in 2011 and during the past two years has been employed mainly forload transportation on mountains. The main innovations adopted by the vehicle are about thesuspension system and the hydrostatic transmission; the combination of both allows acomfortable driving up to a maximum speed of 20 km/h.First of all, the present thesis aims to quantitatively evaluate the performances of the vehiclefrom the point of view of the suspension system and the transmission. The design of the vehicle,in fact, has been driven by the designer’s experience and no preliminary simulations and sizingcomputations have been performed.According to the outcomes of the first step as well as the feedback, some improvements to thecurrent configuration are designed and evaluated. The feedback has been submitted to theprototype’s users through a questionnaire. Improvements are supposed to be easily implementedon the existing vehicle.The outcomes of the previous steps as well as the communication with employees andentrepreneurs and the knowledge of the state of the art in terms of construction and earthmovingmachines drive the last step of the present work.The employees and entrepreneurs consulted mainly work in the agricultural sector and they havebeen contacted through web-based forums. In addition, the participation to the fair Bauma 2013allowed us to get a more complete picture of the state of the art.New solutions, starting from scratch, are designed in the last part.Keywords: / Speed-Track är en prototyp av en spårfarkost utvecklad för materialtransport på gårdar och igallerior. Den konstruerades 2011 och under de senaste två åren har den främst använts för tungatransporter på berg.De huvudsakliga innovationerna av vilka farkosten använder sig av är kopplade tillsuspensionssystemet och den hydrostatiska transmissionen; kombinationen av dessa möjliggören bekväm resa i hastigheter upp till 20 km/h.Målet med detta examensarbete är framför allt att utvärdera prestandan hos farkosten medhänsyn till suspensionssystemet och transmissionen. Designen av farkosten har utformats baseratpå utvecklarens erfarenheter och inga preliminära simuleringar eller beräkningar har utförts.Baserat på resultaten från, och utvärdering av det första steget har vissa förbättringar till denrådande uppbyggnaden framtagits och utvärderats. Utvärderingen har lämnats till användare avprototypen genom ett frågeformulär.Förbättringarna skall vara lätta att tillämpa på den existerande farkosten.Resultaten från de föregående stegen tillsammans med en dialog med anställda och entreprenörersamt teknisk kunskap med avseende på konstruktion och jordfraktande maskiner driva det sistasteget av det presenterade arbetet.Medarbetare och entreprenörer härstammar framför allt från arbete inom jordbrukssektorn ochhar blivit kontaktade genom web-forum.Dessutom har medverkan under mässan Bauma 2013 givit en mer komplett bild av den rådandetekniken.Nya lösningar skapade från början utvecklas i arbetets sista del.
40

DESIGN OF MULTI-MATERIAL STRUCTURES FOR CRASHWORTHINESS USING HYBRID CELLULAR AUTOMATON

Sajjad Raeisi (11205861) 30 July 2021 (has links)
<p>The design of vehicle components for crashworthiness is one of the most challenging problems in the automotive industry. The safety of the occupants during a crash event relies on the energy absorption capability of vehicle structures. Therefore, the body components of a vehicle are required to be lightweight and highly integrated structures. Moreover, reducing vehicle weight is another crucial design requirement since fuel economy is directly related to the mass of a vehicle. In order to address these requirements, various design concepts for vehicle bodies have been proposed using high-strength steel and different aluminum alloys. However, the price factor has always been an obstacle to completely replace regular body steels with more advanced alloys. To this end, the integration of numerical simulation and structural optimization techniques has been widely practiced addressing these requirements. Advancements in nonlinear structural design have shown the promising potential to generate innovative, safe, and lightweight vehicle structures. In addition, the implementation of structural optimization techniques has the capability to shorten the design cycle time for new models. A reduced design cycle time can provide the automakers with an opportunity to stay ahead of their competitors. During the last few decades, enormous structural optimization methods were proposed. A vast majority of these methods use mathematical programming for optimization, a method that relies on availability sensitivity analysis of objective functions. Thus, due to the necessity of sensitivity analyses, these methods remain limited to linear (or partially nonlinear) material models under static loading conditions. In other words, these methods are no able to capture all non-linearities involved in multi-body crash simulation. As an alternative solution, heuristic approaches, which do need sensitivity analyses, have been developed to address structural optimization problems for crashworthiness. The Hybrid Cellular Automaton (HCA), as a bio-inspired algorithm, is a well-practiced heuristic method that has shown promising capabilities in the structural design for vehicle components. The HCA has been continuously developed during the last two decades and designated to solve specific structural design applications. Despite all advancements, some fundamental aspects of the algorithm are still not adequately addressed in the literature. For instance, the HCA numerically implemented as a closed-loop control system. The local controllers, which dictate the design variable updates, need parameter tuning to efficiently solve different sets of problems. Previous studies suggest that one can identify some default values for the controllers. However, still, there is no well-organized strategy to tune these parameters, and proper tuning still relies on the designer’s experience.</p> <p> </p> <p> Moreover, structures with multiple materials have now become one of the perceived necessities for the automotive industry to address vehicle design requirements such as weight, safety, and cost. However, structural design methods for crashworthiness, including the HCA, are mainly applied to binary structural design problems. Furthermore, the conventional methods for the design of multi-material structures do not fully utilize the capabilities of premium materials. In other words, the development of a well-established method for the design of multi-material structures and capable of considering the cost of the materials, bonding between different materials (especially categorical materials), and manufacturing considering is still an open problem. Lastly, the HCA algorithm relies only on one hyper-parameter, the mass fraction, to synthesize structures. For a given problem, the HCA only provides one design option directed by the mass constraint. In other words, the HCA cannot tailor the dynamic response of the structure, namely, intrusion and deceleration profiles.</p> <p> </p> <p>The main objective of this dissertation is to develop new methodologies to design structures for crashworthiness applications. These methods are built upon the HCA algorithm. The first contribution is about introducing s self-tuning scheme for the controller of the algorithm. The proposed strategy eliminates the need to manually tune the controller for different problems and improve the computational performance and numerical stability. The second contribution of this dissertation is to develop a systematic approach to design multi-material crashworthy structures. To this end, the HCA algorithm is integrated with an ordered multi-material SIMP (Solid Isotropic Material with Penalization) interpolation. The proposed multi-material HCA (MMHCA) framework is a computationally efficient method since no additional design variables are introduced. The MMHCA can synthesize multi-material structures subjected to volume fraction constraints. In addition, an elemental bonding method is introduced to simulate the laser welding applied to multi-material structures. The effect of the bonding strength on the final topology designs is studied using numerical simulations. In the last step, after obtaining the multi-material designs, the HCA is implemented to remove the desired number of bonding elements and reduce the weld length.</p> <p> </p> <p>The third contribution of this dissertation is to introduce a new Cluster-based Structural Optimization method (CBSO) for the design of multi-material structures. This contribution introduces a new Cluster Validity Index with manufacturing considerations referred to as CVI<sub>m</sub>. The proposed index can characterize the quality of the cluster in structural design considering volume fraction, size, interface as a measure of manufacturability. This multi-material structural design approach comprises three main steps: generating the conceptual design using adaptive HCA algorithm, clustering of the design domain using Multi-objective Genetic Algorithm (MOGA) optimization. In the third step, MOGA optimization is used to choose categorical materials in order to optimize the crash indicators (e.g., peak intrusion, peak contact force, load uniformity) or the cost of the raw materials. The effectiveness of the algorithm is investigated using numerical examples.</p>

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