Operations research and queue theory have many different applications, providing tremendous value for different organizations. With the rise of fast computers and better data, stochastic processes can be better modeled into simulations to provide results of higher quality. The application of Operations Research is a very interesting intersection of mathematics, statistics, computer science and management science. In this project, the benefits of using point wise stationary approximations and stationary independent period by period approximationsto simulate staffing requirements at LAX (Los Angeles International Airport) in conjuction are examined with the motivation of reducing arrival processing times. This paper then examines the performance of different airport layouts, utilizing a discrete event simulation.

While modeling stochastic systems it is very important results to be examined using reliable statistics analysis. Estimation methods that can allow user to make statistic conclusions about model from simulation results are needed. These methods are also used while determining relation between simulation time and precision of estimations. To complete the task regeneration method was chosen. This method is successfully used in various practical problems solving. The usage of regeneration method is based on the fact that many stochastic systems renovate in a probability sense. Besides regeneration method easily solves such “tactical” problems like: • How to start simulation? • Which moment to start to gather data at? • What to do with strongly correlated data? Received results are confidential intervals of the queue forming in two and three – channel system characteristics (medium waiting time in queue and maximal length of queue). From these results we can judge about effectiveness of system work and relation between results’ precision and simulation time.

Queue buildup is a problem that every fast food restaurant would like to reduce, as its effect on customer satisfaction and restaurant revenue is obviously negative. This thesis looks at how a dynamic menu management system would affect fast food restaurants, specifically how the promotion of fast products, in certain situations, would affect total revenue and queue lengths. A neural network was used to categorize products depending on their preparation time and to predict queue waiting times. A simulation approach was used to find out how the menu management system would affect the restaurant. The results are that in situations where long queues are formed, the promotion of fast products increases revenue by 7.8% and decreases queue lengths by 13.3%. In situations where little to no queues are formed, the same system still decreases queue lengths by 4.7%, but also decreases revenue by 0.2%

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-13T10:55:38Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gustavo Batista de Castro Souza - 2014.pdf: 11760996 bytes, checksum: 8245af285d79ff9e8079bafddb72e690 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-13T10:56:54Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gustavo Batista de Castro Souza - 2014.pdf: 11760996 bytes, checksum: 8245af285d79ff9e8079bafddb72e690 (MD5) / Made available in DSpace on 2015-01-13T10:56:54Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Gustavo Batista de Castro Souza - 2014.pdf: 11760996 bytes, checksum: 8245af285d79ff9e8079bafddb72e690 (MD5) Previous issue date: 2014-07-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Smart Grids systems have become widespread around the world. The RF mesh communication systems have contributed to make power systems smarter and reliable with implementation of Distributed Automation and Demand Response technologies. This work presents a methodology for positioning of GPRS concentrators in a energy meter ZigBee mesh network in order to attain the average network delay, thus aiming to improve the performance of the communication service. The proposed algorithm determines the amount and placement of concentrators using Integer Linear Programming and a Queuing Model for the Mesh Network. The solutions given by the proposed algorithm are validated by verifying the network performance through computer simulations based on real network scenarios. / Smart Grids tem se difundido em todo o mundo. Sistemas de comunicação RF Mesh (em malha) tem contribuído para deixar sistemas de potência mais inteligentes e confiáveis com a implantação de tecnolgias de Automação da Distribuição e Resposta à Demanda. Este trabalho apresenta um metodologia de posicionamento de concentradores GPRS em uma rede ZigBee mesh de medidores de energia elétrica com o objetivo de limitar o delay médio da rede e assim otimizar o desempenho do serviço de comunicação. O algoritmo proposto determina a quantidade e a localização de concentradores utilizando Programação Linear Inteira e um Modelo de Filas para Redes Mesh. As soluções obtidas pelo algoritmo proposto são validadas verificando o desempenho da rede através de simulações computacionais baseadas em cenários reais de redes.