This master's thesis deals with optimization of traffic networks. There are discussed modeling methods for traffic and simplifications used in these models. Introductory part is focused on mathematical theory used to buid presented model. Main focus of this thesis was creation and optimization of the model which describes real world traffic network with traffic lights. Model was tested on both artificial and real data gathered in city Zlín. It was necessary to create generator which can produce suitable input data for model.

The development of sustainable business models is a challenging task since various factors might influence the results of an assessment. Given the complexity at the municipal level, system interdependencies between different alternatives need to be considered. One possibility to support decision makers is to apply energy system optimization models. Existing optimization models, however, ignore the roles different actors play and the resulting impact they have. To address this research issue, this thesis presents an integrated techno-economic optimization framework called IRPopt (Integrated Resource Planning and Optimization). A proven graph-based energy system approach allows the accurate modeling of deployment systems by considering different energy carriers and technical processes. In addition, a graph-based commercial association approach enables the integration of actor-oriented coordination. This is achieved by the explicit modeling of market actors on one layer and technology processes on another layer as well as resource flow interrelations and commercial agreements mechanism among and between the different layers. Using the optimization framework, various optimization problems are solvable on the basis of a generic objective function. For demonstration purposes, this thesis assesses the business models demand response and community storage. The applied examples demonstrate the modeling capabilities of the developed optimization framework. Further, the dispatch results show the usefulness of the described optimization approach.

Statische Codemetriken sind wichtige Indikatoren für die Qualität eines Softwaresystems. Sie beleuchten dabei unterschiedliche Aspekte eines Softwaresystems. Deshalb ist es notwendig, mehrere Codemetriken zu nutzen, um die Qualität eines Softwaresystems in seiner Gesamtheit bewerten zu können. Wünschenswert wäre zudem eine Darstellung, die die Struktur des Gesamtsystems und die Bewertung einzelner Elemente eines Softwaresystems in einer Darstellung kombiniert. Die Arbeit untersucht deshalb, welche Metaphern geeignet sind, um eine solche Darstellung zu ermöglichen. Ein zweites Ziel der Arbeit war es, eine solche Visualisierung automatisch erzeugen zu können. Dafür wurde ein Generator entwickelt, der diese Anforderung erfüllt. Zur Konzeption dieses Generators kamen Techniken aus der generativen Softwareentwicklung zum Einsatz. Bei der Umsetzung des Generators wurde auf Techniken aus der modellgetriebenen Softwareentwicklung zurückgegriffen, vor allem auf Techniken aus dem openArchitectureWare-Framework. Der Generator kann in Eclipse eingebunden werden und ist in der Lage, aus einem Java-Projekt die Struktur und die Metrikwerte automatisch zu extrahieren. Diese Werte werden daraufhin in ein dreidimensionales Modell überführt, das auf dem offenen Extensible 3D Standard basiert. Der Generator ermöglichte zudem die Evaluierung zweier unterschiedlicher Metaphern, die im Rahmen der Arbeit durchgeführt wurde.

In this dissertation, we study two important problems related to additive manufacturing (AM). In the first part, we investigate the economic feasibility of using AM to fabricate biomedical implants at the sites of hospitals AM versus traditional manufacturing (TM). We propose a cost model to quantify the supply-chain level costs associated with the production of biomedical implants using AM technology, and formulate the problem as a two-stage stochastic programming model, which determines the number of AM facilities to be established and volume of product flow between manufacturing facilities and hospitals at a minimum cost. We use the sample average approximation (SAA) approach to obtain solutions to the problem for a real-world case study of hospitals in the state of Mississippi. We find that the ratio between the unit production costs of AM and TM (ATR), demand and product lead time are key cost parameters that determine the economic feasibility of AM. In the second part, we investigate the AM facility deployment approaches which affect both the supply chain network cost and the extent of benefits derived from AM. We formulate the supply chain network cost as a continuous approximation model and use optimization algorithms to determine how centralized or distributed the AM facilities should be and how much raw materials these facilities should order so that the total network cost is minimized. We apply the cost model to a real-world case study of hospitals in 12 states of southeastern USA. We find that the demand for biomedical implants in the region, fixed investment cost of AM machines, personnel cost of operating the machines and transportation cost are the major factors that determine the optimal AM facility deployment configuration. In the last part, we propose an enhanced sample average approximation (eSAA) technique that improves the basic SAA method. The eSAA technique uses clustering and statistical techniques to overcome the sample size issue inherent in basic SAA. Our results from extensive numerical experiments indicate that the eSAA can perform up to 699% faster than the basic SAA, thereby making it a competitive solution approach of choice in large scale stochastic optimization problems.

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O tema de roteamento de veículos é de grande importância na literatura e tem sido amplamente estudada pela sua importância para muitas indústrias. Com a evolução na literatura, mais características foram adicionadas para torná-lo mais próximo de situações reais. Alinhado com esta tendência, este trabalho aborda o problema de roteamento de veículos quando há a terceirização da frota que realiza as entregas. Uma forma de cobrança do frete é por meio de custos escalonados, que são calculados de acordo com o tipo de veículo e a distância percorrida, com valores fixos para cada faixa de distância. Embora seja uma forma comum de trabalho na indústria, nenhum trabalho focado nesta característica foi encontrado na literatura. Este problema é o problema de roteamento de veículos com frota mista, janelas de tempo e custos escalonados (FSMVRPTWSC). Ao abordar este problema, este trabalho apresenta um modelo de programação linear inteira mista que é avaliado em um cenário real da indústria. Além disso, três heurísticas de inserção sequencial são propostas para lidar com problemas maiores. Estes métodos são examinados por meio de testes computacionais em 168 problemas de referência gerados para este problema. Os experimentos numéricos mostram que os métodos são robustos e eficientes, apresentando um bom desempenho em conjuntos de problemas com diversas características. / The theme of vehicle routing is of great importance in the literature and has been widely studied for its relevance to many industries and, throughout the literature, more characteristics have been added to make it closer to real situations. Aligned with this trend, this paper addresses the vehicle routing problem when there is outsourcing of the fleet that delivers goods. One form of freight charging is by scaled costs, which are calculated according to the type of vehicle and the distance traveled, with fixed values for each distance range. Though it is a common form of work in the industry, no work focused on this characteristic was found in the literature. This problem is the fleet size and mix vehicle routing problem with time windows and scaled costs (FSMVRPTWSC). In approaching this problem, this paper presents a mixed integer linear programming model that is evaluated under a real situation scenario. Furthermore, three sequential insertion heuristics are proposed in order to deal with larger problems. These methods are examined through a computational comparative study in 168 benchmark problems generated for this problem. The numerical experiments show that the methods are robust and efficient, performing well in different problem sets.

Στην παρούσα διπλωματική μελέτη, σχεδιάζεται και αναπτύσσεται ένα αξιόπιστο σύστημα βαθμολόγησης και άρα αξιολόγησης των προμηθευτών απαραίτητων σε μία Εφοδιαστική Αλυσίδα Αγαθών και Υπηρεσιών. Η μεθοδολογία περιλαμβάνει: Καθορισμό Ομάδας Αξιολόγησης, Ταξινόμηση Εφοδιαστικών Απαιτήσεων (Supply Positioning) σε υλικά και υπηρεσίες (υψηλής κερδοφορίας, κρίσιμα, μη κρίσιμα, στρατηγικής σημασίας, χαμηλού κόστους & υψηλού κινδύνου), Κατάσταση Κρίσιμων Υλικών και Υπηρεσιών, Επισήμανση Δυνητικών Προμηθευτών, Προεπιλογή Προμηθευτών, Συνεργασία - Συζήτηση με Προμηθευτές, Προσδιορισμό Κριτηρίων επιλογής Προμηθευτών, Συντελεστές Βαρύτητας Κριτηρίων, Ανάπτυξη Ανάλυσης SWOT, Έρευνα για επί πλέον πληροφορίες, Σύνταξη και αποστολή Ερωτηματολογίου – Επεξεργασία, Βαθμολογία Δυνητικών Προμηθευτών, Τήρηση Αρχείου Εγκεκριμένων Προμηθευτών. Εν συνεχεία γίνεται μία επισκόπηση τεσσάρων-πέντε κύριων μεθόδων επιλογής και μία βιβλιογραφική ανασκόπηση των ερευνητικών προσπαθειών. Παρουσιάζονται αναλυτικά τα κριτήρια απόφασης, οι μέθοδοι επιλογής (εξάλειψης ή βελτιστοποίησης), τα χαρακτηριστικά του προβλήματος επιλογής προμηθευτή (στρατηγική απόφαση, συνενωτικοί κανόνες, πολλαπλοί εμπλεκόμενοι-παίκτες & διαμορφωτές λήψης απόφασης, πολλαπλά αντικειμενικά και υποκειμενικά κριτήρια, περιορισμοί τόσο των προμηθευτών όσο και της εταιρείας, και ο πιθανοκρατικός χαρακτήρας του προβλήματος) . Η προσέγγιση απαιτεί η απόφαση να ληφθεί σε δύο στάδια. Στο πρώτο στάδιο, επιλέγουμε τους στρατηγικούς προμηθευτές διαμέσου της εταιρικής στρατηγικής για να επιλεχθούν οι προμηθευτές εκείνοι που εγγυώνται την μακροπρόθεσμη βιωσιμότητα της εταιρείας και το ελάχιστο κατώφλι κάθε κριτηρίου. Στο δεύτερο στάδιο της προσέγγισης αυτής, προτείνεται ένα γραμμικό μοντέλο μικτού ακέραιου προγραμματισμού για να επιλεγούν οι καλύτεροι προμηθευτές και οι απαιτούμενες ποσότητες θεωρώντας τους περιορισμούς τόσο των προμηθευτών όσο και της επιχείρησης. Ο σκοπός αυτού του μοντέλου είναι να μεγιστοποιηθεί η συνάρτηση U που αναπαριστά τον ολικό βαθμό που δίνεται από την ομάδα απόφασης. Προτείνεται ένας τρόπος για να ληφθεί υπόψη η πιθανοκρατική συμπεριφορά των υποψήφιων προμηθευτών. Τέλος, για καλύτερη κατανόηση, παρουσιάζεται ένα αριθμητικό παράδειγμα βελτιστοποίησης α) χωρίς περιορισμούς με την προσέγγιση της μεθόδου Αναλυτικής Ιεράρχησης (AHP) και β) με περιορισμούς. Το παράδειγμα μας δείχνει ότι η μαθηματική προσέγγιση ήταν η καλύτερη μέθοδος η οποία λαμβάνει υπόψη όλους τους περιορισμούς. / In this thesis study, it is designed and developed a reliable system calibration and evaluation of suppliers so necessary in a Supply Chain of Goods and Services. The methodology includes: Evaluation Team Specification, Supply Requirements Sorting (Supply Positioning) for materials and services (high profitability, critical, non-critical, strategic, low cost & high risk), Critical Materials and Services Condition, Potential suppliers Highlight, Suppliers Pre-selection, Cooperation - Discussion with Suppliers, Vendor Selection Criteria Identification,, Criteria Weight Credits, SWOT Analysis Development, Research for additional information, Writing, Editing and sending questionnaires, Potential suppliers Review, Approved Suppliers File Records (Archives). An overview of four to five core selection methods and a literature review of research efforts are following. The decision criteria, the selection methods (optimization or elimination) and the characteristics of the supplier selection problem (strategic decision, conjunctive rules, multiple stakeholders-players & decision makers, multiple objective and subjective criteria, constraints regarding to suppliers and the company, the probabilistic nature of the problem) are presenting in details. This approach requires a decision taken in two stages. In the first stage, we select strategic suppliers through the corporate strategy in order to select those suppliers that guarantee the long term viability of the company and the minimum threshold for each criterion. In the second stage of this approach, it is proposed a mixed-integer linear programming model to select the best suppliers and the required quantities considering the limitations of suppliers and the business as well. The purpose of this model is to maximize the function U representing the overall degree given by the group decision. It is also proposed a way to take into account the probabilistic behavior of supply candidates. Finally, for better understanding, a numerical example of optimization is presented a) without restrictions with the approach of Analytic Hierarchy process (AHP) and b) with restrictions. The example shows that the mathematical approach was the best method which takes into account all the constraints.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The supply chain is broad and includes actions that must serve customers quickly, safely and cost . However , the lack of planning to meet these actions causes a lot of quality in service delivery is compromised , which leads to dissatisfaction for the end consumer. One of the biggest impacts on the speed of deliveries by delivery vehicles is the provision of loading into the trunk , ie , how much easier is access to goods , the faster delivery and, thus , more customers can be served in the same time; which will certainly lead to greater vehicle productivity in number of deliveries per day . This work shows the two main models used in vehicle loading attacked distributors and their impact on delivery time and , as a consequence , the speed to serve customers . A technique for the study of linear two charging models for a company of urban and interurban freight distribution with data from 2006 schedule was used . The results indicate that the loading model with separation of cargoes city is more productive than the most commonly used model , without any kind of separation . It is hoped that this work will assist distribution companies in the speed of customer service and improving the service level of the supply chain . / A cadeia de suprimentos é ampla e envolve ações que devem atender os clientes com rapidez, segurança e baixo custo. Porém, a falta de planejamento para cumprir com essas ações faz com que muito da qualidade na prestação do serviço seja comprometida, o que gera insatisfação para o consumidor final. Um dos maiores impactos na rapidez das entregas por veículos de distribuição é a disposição do carregamento dentro do baú, ou seja, quanto mais fácil for o acesso às mercadorias, mais rápido será a entrega e, com isso, mais clientes poderão ser atendidos no mesmo período de tempo; o que certamente implicará em uma maior produtividade do veículo em número de entregas por dia. Este trabalho mostra os dois principais modelos de carregamento de veículos utilizados em atacados distribuidores e seus impactos no tempo de entrega e, como consequência, a rapidez em atender os clientes. Foi utilizada uma técnica de programação linear para o estudo de dois modelos de carregamento para uma empresa de distribuição urbana e interurbana de mercadorias com dados do ano de 2006. Os resultados encontrados indicam que o modelo de carregamento com separação por cidade das cargas é mais produtivo que o modelo mais comumente usado, sem qualquer tipo de separação. Espera-se que este trabalho auxilie as empresas distribuidoras na rapidez de atendimento aos clientes e na melhoria a do nível de serviço da cadeia de suprimentos. / Mestre em Engenharia Civil

O tema de roteamento de veículos é de grande importância na literatura e tem sido amplamente estudada pela sua importância para muitas indústrias. Com a evolução na literatura, mais características foram adicionadas para torná-lo mais próximo de situações reais. Alinhado com esta tendência, este trabalho aborda o problema de roteamento de veículos quando há a terceirização da frota que realiza as entregas. Uma forma de cobrança do frete é por meio de custos escalonados, que são calculados de acordo com o tipo de veículo e a distância percorrida, com valores fixos para cada faixa de distância. Embora seja uma forma comum de trabalho na indústria, nenhum trabalho focado nesta característica foi encontrado na literatura. Este problema é o problema de roteamento de veículos com frota mista, janelas de tempo e custos escalonados (FSMVRPTWSC). Ao abordar este problema, este trabalho apresenta um modelo de programação linear inteira mista que é avaliado em um cenário real da indústria. Além disso, três heurísticas de inserção sequencial são propostas para lidar com problemas maiores. Estes métodos são examinados por meio de testes computacionais em 168 problemas de referência gerados para este problema. Os experimentos numéricos mostram que os métodos são robustos e eficientes, apresentando um bom desempenho em conjuntos de problemas com diversas características. / The theme of vehicle routing is of great importance in the literature and has been widely studied for its relevance to many industries and, throughout the literature, more characteristics have been added to make it closer to real situations. Aligned with this trend, this paper addresses the vehicle routing problem when there is outsourcing of the fleet that delivers goods. One form of freight charging is by scaled costs, which are calculated according to the type of vehicle and the distance traveled, with fixed values for each distance range. Though it is a common form of work in the industry, no work focused on this characteristic was found in the literature. This problem is the fleet size and mix vehicle routing problem with time windows and scaled costs (FSMVRPTWSC). In approaching this problem, this paper presents a mixed integer linear programming model that is evaluated under a real situation scenario. Furthermore, three sequential insertion heuristics are proposed in order to deal with larger problems. These methods are examined through a computational comparative study in 168 benchmark problems generated for this problem. The numerical experiments show that the methods are robust and efficient, performing well in different problem sets.

Distributed systems are everywhere. From large datacenters to mobile devices, an ever richer assortment of applications and services relies on distributed systems, infrastructure, and protocols. Despite their ubiquity, testing and debugging distributed systems remains notoriously hard. Moreover, aside from inherent design challenges posed by partial failure, concurrency, or asynchrony, there remain significant challenges in the implementation of distributed systems. These programming challenges stem from the increasing complexity of the concurrent activities and reactive behaviors in a distributed system on the one hand, and the need to effectively leverage the parallelism offered by modern multi-core hardware, on the other hand. This thesis contributes Kompics, a programming model designed to alleviate some of these challenges. Kompics is a component model and programming framework for building distributed systems by composing message-passing concurrent components. Systems built with Kompics leverage multi-core machines out of the box, and they can be dynamically reconfigured to support hot software upgrades. A simulation framework enables deterministic execution replay for debugging, testing, and reproducible behavior evaluation for large-scale Kompics distributed systems. The same system code is used for both simulation and production deployment, greatly simplifying the system development, testing, and debugging cycle. We highlight the architectural patterns and abstractions facilitated by Kompics through a case study of a non-trivial distributed key-value storage system. CATS is a scalable, fault-tolerant, elastic, and self-managing key-value store which trades off service availability for guarantees of atomic data consistency and tolerance to network partitions. We present the composition architecture for the numerous protocols employed by the CATS system, as well as our methodology for testing the correctness of key CATS algorithms using the Kompics simulation framework. Results from a comprehensive performance evaluation attest that CATS achieves its claimed properties and delivers a level of performance competitive with similar systems which provide only weaker consistency guarantees. More importantly, this testifies that Kompics admits efficient system implementations. Its use as a teaching framework as well as its use for rapid prototyping, development, and evaluation of a myriad of scalable distributed systems, both within and outside our research group, confirm the practicality of Kompics. / Kompics / CATS / REST