The aim of this Master's Thesis is to create an employee shift work schedule by using selected methods of operations research. The first part is theoretical and deals with the introduction into operational research, specifically in the field of mathematical programming and simulation models, including the possibility of computer processing. This first part highlights important subjects that will be used in the second part, which is practical and is solving a specific problem. Firstly, Cinema City Flora, which provided data for the analysis, is presented. Then there is a solution of the problem in the add-in Solver in MS Excel, and then in the program LINGO. After, a discrete simulation is created in the program SIMUL8. In conclusion, there is a summarization of the main findings and recommendations, comparison of selected methods and their applicability in practice and possibilities of further research.

Quality of service (QoS) is an important consideration in networking, but it is also a significant challenge. Providing QoS guarantees becomes even more challenging when you add the complexities to the network like voice and video applications. This master's thesis focuses on QoS modeling and simulation in discrete event simulation system OMNeT++. The implementation of multiple techniques for QoS simulation is added to OMNeT++ within this work. All implemented modules are validated against the QoS tools on real routers. The last part of the work presents the possibility of QoS simulation in newly implemented modules.

Currently the network centric operation and network centric warfare have generated a new area of research focused on determining how hierarchical organizations composed by human beings and machines make decisions over collaborative environments. One of the most stressful scenarios for these kinds of organizations is the so-called extreme events. This dissertation provides a hybrid simulation methodology based on classical simulation paradigms combined with social network analysis for evaluating and improving the organizational structures and procedures, mainly the incident command systems and plans for facing those extreme events. According to this, we provide a methodology for generating hypotheses and afterwards testing organizational procedures either in real training systems or simulation models with validated data. As long as the organization changes their dyadic relationships dynamically over time, we propose to capture the longitudinal digraph in time and analyze it by means of its adjacency matrix. Thus, by using an object oriented approach, three domains are proposed for better understanding the performance and the surrounding environment of an emergency management organization. System dynamics is used for modeling the critical infrastructure linked to the warning alerts of a given organization at federal, state and local levels. Discrete simulations based on the defined concept of "community of state" enables us to control the complete model. Discrete event simulation allows us to create entities that represent the data and resource flows within the organization. We propose that cognitive models might well be suited in our methodology. For instance, we show how the team performance decays in time, according to the Yerkes-Dodson curve, affecting the measures of performance of the whole organizational system. Accordingly we suggest that the hybrid model could be applied to other types of organizations, such as military peacekeeping operations and joint task forces. Along with providing insight about organizations, the methodology supports the analysis of the "after action review" (AAR), based on collection of data obtained from the command and control systems or the so-called training scenarios. Furthermore, a rich set of mathematical measures arises from the hybrid models such as triad census, dyad census, eigenvalues, utilization, feedback loops, etc., which provides a strong foundation for studying an emergency management organization. Future research will be necessary for analyzing real data and validating the proposed methodology.

<p>VIRTUAL PROTOTYPING has been generally adopted in product development in order to minimise the traditional reliance on testing of physical prototypes. It thus constitutes a major step towards solving the conflict of actual increasing development cost and time due to increasing customer demands on one side, and the need to decrease development cost and time due to increasing competition on the other. Particularly challenging for the off-road equipment industry is that its products, working machines, are complex in architecture. Tightly coupled, non-linear sub-systems of different technical domains make prediction and optimisation of the complete system’s dynamic behaviour difficult.</p><p>Furthermore, in working machines the human operator is essential for the performance of the total system. Properties such as productivity, fuel efficiency, and operability are all not only dependent on inherent machine properties and working place conditions, but also on how the operator uses the machine. This is an aspect that is traditionally neglected in dynamic simulations, because the modelling needs to be extended beyond the technical system.</p><p>The research presented in this thesis focuses on wheel loaders, which are representative for working machines. The technical system and the influence of the human operator is analysed, and so-called short loading cycles are described in depth. Two approaches to rule-based simulation models of a wheel loader operator are presented and used in simulations. Both operator models control the machine model by means of engine throttle, lift and tilt lever, steering wheel, and brake only – just as a human operator does. Also, only signals that a human operator can sense are used in the models. It is demonstrated that both operator models are able to adapt to basic variations in workplace setup and machine capability. Thus, a “human element” can be introduced into dynamic simulation of working machines, giving more relevant answers with respect to operator-influenced complete-machine properties such as productivity, fuel efficiency, and operability already in the concept phase of the product development process.</p> / ISRN/Report code: LiU-Tek-Lic 2005:44

O gerenciamento de projetos assume um papel cada vez mais importante nas atividades empresariais. Os projetos têm papel importante na sobrevivência da empresa. Assim, uma sistemática eficiente para o gerenciamento de seus projetos atenderá aos padrões do mercado na questão de custos e prazo. A eficiência dos sistemas produtivos também tem grande importância. Neste cenário as empresas devem possuir uma sistemática eficiente para a otimização do sistema produtivo a fim de obter-se um sistema eficaz. O presente trabalho traz duas propostas para melhoria destes problemas, o primeiro é o desenvolvimento de uma metodologia para gerenciamento de projetos e o segundo uma metodologia de otimização do sistema produtivo utilizando Redes de Petri auxiliado por simulação discreta. Para comprovar a eficácia destas propostas, um estudo de caso foi realizado em uma empresa. / The management of projects assumes a role nowadays each more important time in the enterprise activities. In manufacture companies who work in an environment under order, the projects have important paper in the survival of the company. Thus, these companies must possess an efficient systematics for the management of its projects, in order to take care of to the standards, each limited time more, of cost, stated period and quality of its customers. The efficiency of the productive systems also has great importance in the activities entrepreneurs now a day. The companies who do not present efficient a productive system do not obtain to compete in equality in this globalizado world, in this scene the companies must possess an efficient systematics for the optimization and the simulation of the productive system in order to arrive at an efficient system. The present work brings two proposals for improvement of these problems, the first one is developing of a methodology for management of projects and as a methodology of optimization of the productive system using nets of Petri assisted for discrete simulation, and to prove the effectiveness of these proposals a case study it was elaborated in a company in order to get itself resulted for the evidence of the elaborated proposals.

En condition accidentelle,le combustible nucléaire d’un réacteur peut entrer en contact avec le fluide caloporteur.Les conséquences de l’interaction qui en résulte sont étudiées par l’IRSN. La violence de l’interaction dépend notamment fortement de la cinétique de cette mise en contact. L’observation expérimentale directe du phénomène étant inenvisageable. Ce travail de thèse a consisté en l’étude de cette dynamique. Nous avons étudié le débit de vidange d’un milieu granulaire monodisperse en fonction de plusieurs paramètres prépondérants (géométrie du réservoir,taille,forme et position de l’orifice,débit gazeux,taille des grains). Ces études ont été réalisées sur un banc expérimental dédié et ont mis en évidence plusieurs lois d’échelle pour le régime stationnaire. En support à l’interprétation de ces expériences, différentes hypothèses de modélisation de l’écoulement (population discrète de particules, rhéologie d’un milieu continu) ont été confrontées aux résultats expérimentaux à l’aide de simulations numériques. Ainsi la loi de dépendance classique du débit de vidange d’un silo avec un orifice en bas a été étendue aux silos avec un orifice latéral notamment en clarifiant les contributions relatives aux dimensions verticale et horizontale. Par ailleurs, il a été établi qu’un écoulement de gaz augmente significativement le débit de vidange du granulaire. Ceci peut être modélisé en prenant en compte le gradient de pression imposé par le gaz sur les grains dans la zone de l’orifice en plus de la gravité. Les éléments fondateurs de la modélisation d’une vidange de grains et de gaz au sein d’un réservoir avec un orifice latéral ont pu ainsi être mis en place. / In the hypothetical conditions of a reactivity initiated accident in a nuclear power plant, some of the cylindrical rods, that contain the fuel, could break. If fuel fragmentation occurs, hot fuel particles and pressurized gas could be ejected out of the rod and then interact with the surrounding fluid. The consequences of this interaction are studied by IRSN . The violence of this interaction depends particularly on the discharge rate of the fuel particles. The aim of this thesis, was to study this dynamics. We simulated the fuel particles and gas ejection dynamics by the flow of a dense granular material and a gas from a confined space toward an open space. We focused on the experimental study of the stationary discharge of a silo composed of monodisperse spherical glass beads, with an orifice either lateral or at the bottom of the silo, with or without air flow. The measured parameters were the mass flow rate and the pressure along the silo, whereas the controlled parameters were the size of particles, the size of orifices, and the flow rate of air. To understand the underlying physical mechanism, discrete and continuous numerical simulations were also performed and compared to the experimental results. For the case of a lateral orifice, when the form of the orifice is rectangular, we identified two regimes that depend on the ratio of width to height. For the case with air flow, we found that the flow rate increases significantly with the air flow. We used a simple physical model to describe the grains and gas ejection taking into account the pressure gradient imposed by the fluid on the particles around the orifice.

Different paths for trains throughout a railway system are more or less convenient, where intersecting train paths require a safety margin in time between different trains to reduce the risks of accidents. Intersecting train paths are just as much of a challenge on a railway station, especially when multiple trains are entering the station close in time. Some trains might have to wait before entering the station area, which as a result create delays that can affect other trains and passengers. One method of reducing the delay is by allocating trains efficiently to different platforms on the station, which makes it possible for more trains to be at the station at the same time. The purpose of this report was to investigate the effect of different platform allocation strategies in regard to the punctuality of trains, passengers’ convenience, travel time in the system as well as the delay compared to arrival and departure times. Three research questions were formulated to answer to the purpose, which included how a reduction in platforms affect the railway system, how different strategies affect walking time for passengers and whether it was possible to prioritize different train types to different platforms. To investigate how different platform allocation strategies affect the railway system, simulation as a method was used. With simulation, a model could be constructed similar to the real system, which made it possible to perform different experiments quickly without any impact on the real system. Linköping Central Station was chosen as a test case as it was both reasonably large and geographically close for observations. Four experiments were constructed, with four separate platform allocation strategies, all aimed to answer some part of the purpose. Before conducting the experiments, a base scenario was tested that attempted to mimic the current platforming strategy as much as possible and was used to compare the different experiments to. This thesis demonstrates that several different platform allocation strategies are possible to be used in the test case, where a risk of train delays were present when the number of tracks used were decreased. With the help of the experiments, the three research questions and therefore the purpose of the study have been answered. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>

The diploma thesis focuses on the manufacturing order management in company. It contains examples of production systems and their analysis for optimization. During the optimization are monitored major criteria, for example: increase of production rate, resource utilization, and so on. The result of this work is a proposed solutionarising from the outputs of optimization the manufacturing system.

OMNeT++ is a discrete event, modular simulator often used for simulation of computer networks. The universal simulator can be extended by various packages, such as INET framework, which is used for simulation of devices and TCP/IP protocols. This thesis examines facilities of INET package in the routing that is dynamic routing protocols. Concretely, it aims at OSPF protocol for IPv6 networks (OSPFv3). The protocol is presented and its principles are interpreted. The work is designed to simulate the module OSPFv3 protocol and module is partially implemented.

VIRTUAL PROTOTYPING has been generally adopted in product development in order to minimise the traditional reliance on testing of physical prototypes. It thus constitutes a major step towards solving the conflict of actual increasing development cost and time due to increasing customer demands on one side, and the need to decrease development cost and time due to increasing competition on the other. Particularly challenging for the off-road equipment industry is that its products, working machines, are complex in architecture. Tightly coupled, non-linear sub-systems of different technical domains make prediction and optimisation of the complete system’s dynamic behaviour difficult. Furthermore, in working machines the human operator is essential for the performance of the total system. Properties such as productivity, fuel efficiency, and operability are all not only dependent on inherent machine properties and working place conditions, but also on how the operator uses the machine. This is an aspect that is traditionally neglected in dynamic simulations, because the modelling needs to be extended beyond the technical system. The research presented in this thesis focuses on wheel loaders, which are representative for working machines. The technical system and the influence of the human operator is analysed, and so-called short loading cycles are described in depth. Two approaches to rule-based simulation models of a wheel loader operator are presented and used in simulations. Both operator models control the machine model by means of engine throttle, lift and tilt lever, steering wheel, and brake only – just as a human operator does. Also, only signals that a human operator can sense are used in the models. It is demonstrated that both operator models are able to adapt to basic variations in workplace setup and machine capability. Thus, a “human element” can be introduced into dynamic simulation of working machines, giving more relevant answers with respect to operator-influenced complete-machine properties such as productivity, fuel efficiency, and operability already in the concept phase of the product development process. / <p>ISRN/Report code: LiU-Tek-Lic 2005:44</p>