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The most used design approach for civil engineering structures is a trial and error procedure; the designer chooses an initial configuration, tests it and changes it until all safety requirements are met with good material utilization. Such a procedure is time consuming and eventually leads to a feasible solution, while several better ones could be found. Indeed, together with safety, environmental impact and investment cost should be decisive factors for the selection of structural solutions. Thus, structural optimization with respect to environmental impact and cost has been the subject of many researches in the last decades. However, design techniques based on optimization haven’t replaced the traditional design procedure yet. One of the reasons might be the constructive feasibility of the optimal solution. Moreover, concerning reinforced concrete beam bridges, to the best of the author knowledge, no study in the literature has been published dealing with the optimization of the entire bridge including both the structural configuration and cross-section dimensions. In this thesis, a two-steps automatic design and optimization procedure for reinforced concrete road beam bridges is presented. The optimization procedure finds the solution that minimizes the investment cost and the environmental impact of the bridge, while fulfilling all requirements of Eurocodes. In the first step, given the soil morphology and the two points to connect, it selects the optimal number of spans, type of piers-deck connections and piers location taking into account any obstacle the bridge has to cross. In the second and final step, it finds the optimal dimensions of the deck cross-section and produces the detailed reinforcement design. Constructability is considered and quantified within the investment cost to avoid a merely theoretical optimization. The wellknown Genetic Algorithm (GA) and Pattern Search optimization algorithms have been used. However, to reduce the computational effort and make the procedure more user-friendly, a memory system has been integrated and a modified version of GA has been developed. Moreover, the design and optimization procedure is used to study the relationship between the optimal solutions concerning investment cost and environmental impact. One case study concerning the re-design of an existing road bridge is presented. Potential savings obtained using the proposed method instead of the classic design procedure are presented. Finally, parametric studies on the total bridge length have been carried out and guidelines for designers have been produced regarding the optimal number of spans. / <p>QC 20190304</p>

The configurable computing research community has provided a wealth of evidence that computational platforms based on FPGA technology are capable of cost-effectively accelerating certain kinds of computations. One actively growing area in the research community examines the benefits to computation that can be gained by reconfiguring the FPGAs in a system during the execution of an application. This technique is commonly referred to as run-time reconfiguration. Widespread acceptance of run-time reconfigurable custom computing depends upon the existence of high-level automated design tools. Given the wide variety of available platforms and the rate that the technology is evolving, a set of architecturally independent tools that provide the ability to port applications between different architectures will allow application-based intellectual property to be easily migrated between platforms. A Java implementation of such a toolset, called Janus, is presented and analyzed here. In this environment, developers create a Java class that describes the structural behavior of an application. The design framework allows hardware and software modules to be freely intermixed. During the compilation phase of the development process, the Janus tools analyze the structure of the application and adapt it to the target architecture. Janus is capable of structuring the run-time behavior of an application to take advantage of the resources available on the platform. Examples of applications developed using the toolset are presented. The performance of the applications is reported. The retargeting of applications for multiple hardware architectures is demonstrated. / Ph. D.

Adoption of a streamlined BIM workflow throughout the AEC projects’ lifecycle will provide the project stakeholders with the rich information embedded in the parametric design models. Users can incorporate this rich information in various activities, improving efficiency and productivity of project activities and potentially enhancing accuracy and reducing errors and reworks. Two main challenges for such a streamlined information flow throughout the AEC projects that haven’t been sufficiently addressed by previous research efforts include lack of semantic interoperability and a large gap and misalignment of information between available BIM information provided by design activities and the required information for performing preconstruction and construction activities. This research effort proposes a framework for a knowledge-based system (KBS) that encapsulates domain experts’ knowledge and represents it through modularized rule set libraries as well as connected design automation and optimization solutions. The research attempts to provide a methodology for automatic semantic enrichment of design models as well as automated detailed design to fill the information gap between design and preconstruction project activities, streamlining BIM workflow and enhancing its value in the AEC projects.

There are different phases in any design activity, one of them being concept generation. Research in automating the conceptual design process in planar mechanisms is always challenging due to the existence of many different elements and their endless combinations. There may be instances where designers arrive at a concept without considering all the alternatives. Computational synthesis aims to arrive at a design by considering the entire space of valid designs. Different researchers have adopted various methods to automate the design process that includes existence of similar graph grammar approaches. But few methods replicate the way humans’ design. An attempt is being made in the thesis in this direction and as a first step, we focus on representing and evaluating planar mechanisms designed using graph grammars. Graph grammars have been used to represent planar mechanisms but there are disadvantages in the methods currently available. This is due to the lack of information in understanding the details of a mechanism represented by the graph since the graphs do not include information about the type of joints and components such as revolute links, prismatic blocks, gears and cams. In order to overcome drawbacks in the existing methods, a novel representation scheme has been developed. In this method, labels and x, y position information in the nodes are used to represent the different mechanism types. A set of sixteen grammar rules that construct different mechanisms from the basic seed is developed, which implicitly represents a tree of candidate solutions. The scheme is tested to determine its capability in capturing the entire set of feasible planar mechanisms of one degree of freedom including Stephenson and double butterfly linkages. In addition to the representation, another important consideration is the need for an accurate and generalized evaluator for kinematic analysis of mechanisms which, given the lack of information, may not be possible with current design automation schemes. The approach employed for analysis is purely kinematic and hence the instantaneous center of rotation method is employed in this research. The velocities of pivots and links are obtained using the instant center method. Once velocities are determined, the vector polygon approach is used to obtain accelerations and geometrical intersection to determine positions of pivots. The graph grammar based analysis module is implemented in an existing object-oriented grammar framework and the results have found this to be superior to or equivalent to existing commercial packages such as Working Model and SAM for topologies consisting of four-bar loop chain with single degree of freedom. / text

Aujourd’hui, la conception ne porte plus sur de simples objets, mais sur des systèmes complexes, sociotechniques et ouverts. Les systèmes de conduite de procédés font partie de ce type de systèmes, où les performances du système reposent sur l’optimisation conjointe des composantes humaines et techniques. Afin de limiter la détection d’erreur tardive, il devient alors important de pouvoir effectuer des tests tout au long de la conception, sans augmenter les coûts et les délais de conception. L’objectif de nos travaux est de faciliter l’intégration de techniques de vérification par simulation, dès le début de la conception, pour des systèmes de conduite de procédés de type gestion de fluide. Pour tenir compte du caractère adaptable du système et de son évolution dans un environnement dynamique, une première contribution porte sur la démarche de vérification, basée sur la formalisation et la contextualisation des propriétés à vérifier. Puis, afin de faciliter l’obtention des modèles de simulation du procédé nécessaires à la mise en œuvre des vérifications tout au long de la conception, nous proposons une approche de génération automatisée des modèles de simulation du procédé dans le langage Modelica (modélisation multi-domaine), à partir d’un schéma P&ID (représentation de l’architecture fonctionnelle du procédé) et d’une bibliothèque d’éléments (contenant les modèles de simulation des éléments). L’implémentation de cette approche dans le cadre du flot de conception automatisée de contrôle- commande d’Anaxagore permet d’apporter une preuve de concept et une preuve d’usage de nos propositions. / Nowadays, engineers have to design open, complex and sociotechnical systems. The process control systems belong to this class of systems, in which the system performance relies on the joint optimisation of technical components and human components. To avoid the late discovery of design errors, it is necessary to perform tests throughout the design without adding design costs and delays. The aim of this work is therefore to facilitate the integration of checking by simulation, from early design stage, for process control systems such as fluid management systems. Regarding the adaptable feature of the system and its evolution in a dynamic environment, a first contribution focusses on the verification approach, by modelling the requirements within the context. Then, to facilitate the obtaining of the process simulation models required for checking throughout the design, we propose an automatic generation approach of simulation models in Modelica language (multi-domain modelling), from a P&ID model (modelling of the functional architecture of the process) and a library of elements (containing the simulation models of elements). To provide a proof of concept and a proof of use of our proposals, this approach has been implemented into Anaxagore, an automated design flow for monitoring and control.

Baigiamajame magistro darbe nagrinėjamos liejimo slegiant formų projektavimo, ga-mybos technologinio paruošimo bei gamybos proceso problemos ir aptariami novatoriški jų sprendimo būdai. Apžvelgiami plastinių medžiagų perdirbimo procesai. Analizuojamas tradi-cinis liejimo slegiant formų gamybos procesas ir jo trūkumai. Pateikiami organizaciniai ir te-chniniai tradicinio gamybos proceso tobulinimo būdai, panaudojant naujausią programinę įrangą, įrankius, medžiagas ir stakles. Tiriamojoje dalyje atliekamas ruošinio parinkimo įtakos liejimo formos detalių savikainai modeliavimas. Išanalizavus visas liejimo slegiant formų ga-mybos problemas, pateikiamos baigiamojo darbo išvados ir siūlymai. Darbą sudaro 7 dalys: įvadas, plastikų perdirbimas, tradicinio liejimo slegiant formų gamybos proceso analizė, liejimo slegiant formų gamybos proceso šiuolaikinės tobulinimo kryptys, ruošinio parinkimo įtakos liejimo formos detalių savikainai modeliavimas, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis – 73 p. teksto be priedų, 50 iliustr., 14 lent., 21 bibliografinis šaltinis. Atskirai pridedami darbo priedai. / In this final master work are investigated plastic injection moulds design, production technological preparation and production problems and discussed innovative solution ways of these problems. Reviewed remake processes of plastic meterials. Analysed tradicional plastic injection mould production process and its weaknesses. Gived organizational and technical tra-dicional production process improvement ways handling the modern software, tools, materials and machines. In investigational part is performed modeling of billet selection influence to cost price of mould parts. After analysis of all the plastic injection moulds production problems gived conclusions and suggestions of this final work. Structure: introduction, remake of plastics, traditional plastic injection moulds production process analysis, modern improvement ways of plastic injection moulds production process, modeling of billet selection influence to cost price of mould parts, conclusions and suggestions, references. Thesis consist of: 73 p. text without appendixes, 50 pictures, 14 tables, 21 bibliographi-cal entries. Appendixes included.

The challenges in automating the design of planar mechanisms are tremendous especially in areas related to computational representation, kinematic analysis and synthesis of planar mechanisms. The challenge in computational representation relates to the development of a comprehensive methodology to completely define and manipulate the topologies of planar mechanisms while in kinematic analysis, the challenge is primarily in the development of generalized analysis routines to analyze different mechanism topologies. Combining the aforementioned challenges along with appropriate optimization algorithms to synthesize planar mechanisms for different user-defined applications presents the final challenge in the automated design of planar mechanisms. The methods presented in the literature demonstrate synthesis of standard four-bar and six-bar mechanisms with revolute and prismatic joints. But a detailed review of these methods point to the fact that they are not scalable when the topologies and the parameters of n-bar mechanisms are required to be simultaneously synthesized. Through this research, a comprehensive and scalable methodology for synthesizing different mechanism topologies and their parameters simultaneously is presented that overcomes the limitations in different challenge areas in the following ways. In representation, a graph-grammar based scheme for planar mechanisms is developed to completely describe the topology of a mechanism. Grammar rules are developed in conjunction with this representation scheme to generate different mechanism topologies in a tree-search process. In analysis, a generic kinematic analysis routine is developed to automatically analyze one-degree of freedom mechanisms consisting of revolute and prismatic joints. Two implementations of kinematic analysis have been included. The first implementation involves the use of graphical methods for position and velocity analyses and the equation method for acceleration analysis for mechanisms with a four-bar loop. The second implementation involves the use of an optimization-based method that has been developed to handle position kinematics of indeterminate mechanisms while the velocity and acceleration analyses of such mechanisms are carried out by formulating appropriate linear equations. The representation and analysis schemes are integrated to parametrically synthesize different mechanism topologies using a hybrid implementation of Particle Swarm Optimization and Nelder-Mead simplex algorithm. The hybrid implementation is able to produce better results for the problems found in the literature using a four-bar mechanism with revolute joints as well as through other higher order mechanisms from the design space. The implementation has also been tested on three new challenge problems with satisfactory results subject to computational constraints. The difficulties in the search have been studied that indicates the reasons for the lack of solution repeatability. This dissertation concludes with a discussion of the results and future directions. / text

This work deals with addressing the issues related to design of double toggle switch mechanisms with emphasis on structural, dimensional and dynamic aspects. Currently, almost all the issues related to electrical switches are dealt from electromagnetic point of view; the operating mechanism is hardly touched. It is observed that kinematic parameters influence electrical performance of switch significantly. Therefore, there is a need to develop methodologies for supporting exploration of diverse kinematic chains (KCs) for this purpose. Visual inspection is tedious and error prone even when a complete list of design criteria is available, hence, the work presented in the thesis contributes towards automated design of toggle switch mechanisms. In this context, in house modular kinematics data structure is found useful for using it as a tool in the design of toggle switch. Modular kinematics, typically used for kinematic analysis, works on the principle of finding the configuration of a mechanism using a given set of modules by a procedure called module sequence. This module sequence is used and interpreted in a number of ways for its effective use in various design stages. Structurally, a set of seven conditions must be satisfied by a KC to exhibit double toggle. These conditions are broadly classified into three categories: criteria for KC, function assignment criteria and criteria for stoppers. These three criteria are to be checked automatically by use of module sequence in the same order as mentioned. In the criteria for KC, one of the conditions is that, the KC should not have fractionated degrees of freedom (d.o.f.). Hence, detection of fractionation in a KC is inevitable. In literature, is was found that the algorithms for detection operate at their worst case complexity, O(n4), and some of them do not report joint fractionation. Thus, the algorithms are not only robust but also computationally expensive. Therefore, a frugal and comprehensive method O(n2) is implemented to detect fractionation using modular kinematics. Also, inherent structural pattern embedded in fractionated KCs is hardly studied in literature. It is found that the way body and joint fractionation is defined in fractionated KCs is inconsistent. So, fractionation is interpreted as symbolic partitioning of joints and links in the traditional body and joint fractionation types respectively. Based on the number of ways of partitioning, simple and multiple types of fractionation are recognized. Valid partitions are identified using the notion of fractionating and non-fractionating subchains. Relative locations of these subchains influence distribution of d.o.f. across the fractionated KC. Conventional representation of KCs as links and joints or graphs is difficult to comprehend this distribution. For this, a novel concept of fractionation graph is introduced that gives d.o.f. distribution information and the relative locations of the constituent subchains across the KC. Modular kinematics gives a constructive description of fractionated KCs. Characterization of fractionated KCs, based on presence of multiple separation links, is introduced as order of fractionation. Uniqueness for a given order of fractionation is also justified. After the criteria for KC, a KC is tested for feasibility for function assignment criteria. This requires recognition of active and passive subchains of the KC with respect to input and output pairs. For this, module sequence is characterized for recognition of the subchains. Based on these subchains, locations of stoppers are derived. Using this information, an algorithmic approach to assign functions (functions like spring, ground link, input link, etc.) to derive distinct driving mechanisms provided isomorphic elements (links and joints) of the KC are known beforehand, is introduced. The design parameters influencing dimensional synthesis have been identified as dimensions of links, spring anchor points and stopper locations. Sub-problems associated with each parameter are analyzed. It is found out that optimum location of stoppers for selecting operational range of motion is necessary by taking into account the considerations of timing of switch and impact velocity. Based on the analysis, an algorithmic way to design single toggle switch mechanisms is introduced. Timing for closing or opening of a switch is one of the critical measure that determines its performance. Timing should be as low as possible without exceeding the impact velocity at the instant contacts meet each other. Timing of a switch depends on the dimensions of the links, inertial parameters, spring stiffness etc. For a given timing for a mechanism, dynamic synthesis, in this thesis, deals with finding the inertial parameters of the links using Quinn's energy distribution method, modular kinematics, and Nelder and Mead's downhill simplex method for optimization. This thesis helps the designer to use modular kinematics as a potential automated tool to select a valid design to make the solution space more meaningful in the design of toggle switch mechanisms.

A process that historically has been hard to automate is interior design, mainly due to its subjective nature and lack of obvious guidelines. Scientifically, there is interest to examine if subjective processes can be automated using black box algorithms such as neural networks, as well as corporate interest in this subject to increase efficiency and create systems for automated floor plan design. This work focuses on finding the limitations of such a project, mainly in establishing the threshold of data points needed for an algorithm in this area to generate relevant results as well as an investigation into requirements to make systems of this kind incorporated in a production pipeline. In this work floor plans with functional area division were set out to be generated using a conditional, generative, adversarial network, cGAN. The system is applied on a use-case provided by NORNORM, a company providing a circular, subscription-based furnishing service for office spaces, also providing data in the form of floor plans. The algorithm is inspired by Yang et al.’s stateof-the-art model from 2019 and the network is tested with three data sets of different sizes, consisting of 100, 500 and 1000 floor plans respectively. This work includes a quantitative evaluation inspired by by Di and Yu, using the average intersection over union metric. Additionally, this work proposes a qualitative evaluation. The qualitative evaluation is carried out using interior designers, posed with a subjective, two-alternative, forced-choice (2AFC) approval or disapproval of the design as a first draft to a customer. This evaluation was not conducted due to insufficient results. The generated results suggests that the threshold for data lies above 1000 data points and, compared to the work by Yang et al., below 4000 data points, the quantitative evaluation concurred with this statement. This interval could be narrowed in future work. In relation as to whether or not the system could be production ready there are a few requirements unachieved, for instance automated data collection and preprocessing. Future work could include conducting the qualitative evaluation on a future implementation of this system. / Historiskt sett har subjektiva processer så som inredningsdesign varit svåra att automatisera, på grund av avsaknad av formella processer och riktlinjer. Det finns ett vetenskapligt intresse i att undersöka om processer som inredningsdesign kan automatiseras med hjälp av algoritmer eller neurala nätverk, men även ett industriellt intresse för att minimera resurser som läggs på detta. Det här projektet fokuserar på att hitta begränsningar av sådana system genom att fokusera på att hitta lägsta möjliga mängd data för att generera relevanta resultat samt undersöka vad som krävs för att använda systemet i produktion. I samarbete med företaget NORNORM skapades ett villkorligt generativt motståndsnätverk i syfte att generera planlösningar med funktionsområdesindelning. NORNORM är ett cirkulärt företag som erbjuder en abonnemangsbaserad tjänst för inredning av kontorslokaler och bidrog med data i form av färdiginredda planlösningar. Algoritmen som används är inspirerad av Yang et al.’s modell från 2019 som ligger i den vetenskapliga framkanten. Nätverket testades med tre olika dataset, som bestod av 100, 500 och 1000 datapunkter. Nätverket utvärderades kvantitativt med en utvärdering inspirerad av Di and Yu, som använder genomsnittlig skärningspunkt över union. Utöver detta föreslås en kvalitativ utvärdering i detta arbete, som utförs med utbildade interiördesigners. Varje desginer utsätts för ett subjektiv val att godkänna eller underkänna en design som ett första utkast till en kund. Utvärderingsmodellen användes inte i det här projektet på grund av bristande resultat. Den genererade resultaten visar att gränser för antalet datapunkter som krävs för att generera relevanta resultat ligger mellan 1000 och 4000 datapunkter, vilket styrks av den kvatitativa utvärderingen. Detta intervall kan förslagsvis avsmalna i framtida projekt. Vidare kräver systemet ett antal premisser för att kunna vara redo för produktion, till exempel automatiserad datainhämtning och behandlande. Framtida projekt kan utföra den föreslagna kvalitativa utvärderingen på liknande system.