Despite the superior properties of Fibre Reinforced Polymer (FRP) materials, the use of FRPs in buildings is limited. A key cause of concern for their use in buildings arises from their poor performance in fire occurrences. This thesis presents the results of fire performance of Reinforced Concrete (RC) beams and slabs strengthened with externally bonded FRP sheets. The performance and effectiveness of insulation materials and techniques are also investigated in this thesis. Two full-scale reinforced concrete T-beams and two intermediate-scale slabs were strengthened in flexure with carbon and glass fibre reinforced polymer sheets and insulated with a layer of spray-on material. The T-beams and slabs were then exposed to a standard fire. Fire test results show that fire endurances of more than 4 h can be achieved using an appropriate insulation system. Tests were performed in order to understand the behaviour of FRP concrete bond at high temperatures. An empirical model was then formulated to describe the bond strength deterioration due to temperature rise. Innovative measurement techniques were employed throughout the experiments to measure important observables like strain and temperature. Meanwhile, the effectiveness and practicality of techniques such as Fibre Optic Sensing (FOS) and Particle Image Velocimetry (PIV) for high temperature applications were investigated. A numerical finite-volume heat transfer model was developed to simulate the heat transfer phenomenon. The validity of the numerical model was verified by comparing the results with the results from the fire tests. By using this model, parametric analyses were performed to investigate the effect of different fire scenarios on the performance of the insulated beams. To simulate the structural performance of the T-beams a numerical model which was capable of predicting stresses and strains and deflections of a heated beam was developed. The model is capable of incorporating the effects of axial forces in the response of a restrained beam. This model was verified and used in combination with the thermal model to simulate the deflections of T-beams in fire. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2013-09-17 15:11:16.185

The thesis deals with optimization of network flow monitoring. Flow-based network traffic processing, that is, processing packets based on some state information associated to the flows which the packets belong to, is a key enabler for a variety of network services and applications. The number of simultaneous flows increases with the growing number of new services and applications. It has become a challenge to keep a state per each flow in a network device processing high speed traffic. A flow table, a structure with flow states, must be stored in a memory hierarchy. The memory closest to the processing is known as a flow cache. Flow cache management plays an important role in terms of its effective utilization, which affects the performance of the whole system. This thesis focuses on an automated design of cache replacement policy optimized to a deployment on particular networks. A genetic algorithm is proposed to automate this process. The genetic algorithm generates and evaluates evolved replacement policies by a simulation on obtained traffic traces. The proposed algorithm is evaluated by designing replacement policies for two variations of the cache management problem. The first variation is an evolution of the replacement policy with an overall low number of state evictions from the flow cache. The second variation represents an evolution of the replacement policy with a low number of evictions belonging to large flows only. Optimized replacement policies for both variations are found while experimenting with various encoding of the replacement policy and genetic operators. The newly evolved replacement policies achieve better results than other tested policies. The evolved replacement policy lowers the overall amount of evictions by ten percent in comparison with the best compared policy. The evolved replacement policy focusing on large flows lowers the amount of their evictions two times. Moreover, no eviction occurs for most of the large flows (over 90%). The evolved replacement policy offers better resilience against flooding the flow cache with large amount of short flows which are typical side effects of scanning or distributed denial of service activities. An extension of the replacement policy is also proposed. The extension complements the replacement policy with an additional information extracted from packet headers. The results show further decrease in the number of evictions when the extension is used.

No presente trabalho é proposto um modelo de simulação de uma cadeia de suprimentos integrada com adoção da estratégia de VMI (Vendor Managed Inventory) entre uma empresa do setor de minério de ferro e alguns de seus fornecedores estratégicos. O modelo baseia-se em uma estrutura de avaliação de sistemas VMI adaptada de Sarpola et al. (2007) em conjunto com as configurações de cadeias de suprimentos propostas por Holmström et al (2003), o que permite medir o desempenho da cadeia de suprimentos segundo 3 níveis de integração. É feita uma revisão bibliográfica dos conceitos da estratégia de VMI, políticas de estoque em sistemas integrados, compartilhamento e grau de visibilidade de informações ao longo da cadeia de suprimentos. Os resultados obtidos possibilitam realizar uma análise quantitativa dos benefícios do VMI, onde são considerados demanda estocástica, lead time aleatório, produtos com características diferentes, compartilhamento de informações, visibilidade parcial da cadeia de suprimentos, lotes variáveis, cálculo dos estoques de segurança considerando informações dos pedidos, demanda real do cliente e erros de previsão. / In this paper we proposed a simulation model of an integrated supply chain with the adoption of VMI (Vendor Managed Inventory) strategy between a company of the iron ore and some of its strategic suppliers. The model is based on a framework for evaluating VMI systems adapted from Sarpola et al. (2007) together with the configurations of supply chains proposed by Holmström et al (2003), which measures the performance of the supply chain using 3 levels of integration. It is a literature review of the concepts of the strategy of VMI, inventory policies in integrated systems, sharing and degree of visibility of information throughout the supply chain. The results allowed to perform a quantitative analysis of the benefits of VMI, which are considered as stochastic demand, random lead time, products with different characteristics, information sharing, partial visibility of the supply chain, lots of variables, calculation of safety stocks based on information from client orders, actual customer demand and forecasting errors.

No presente trabalho é proposto um modelo de simulação de uma cadeia de suprimentos integrada com adoção da estratégia de VMI (Vendor Managed Inventory) entre uma empresa do setor de minério de ferro e alguns de seus fornecedores estratégicos. O modelo baseia-se em uma estrutura de avaliação de sistemas VMI adaptada de Sarpola et al. (2007) em conjunto com as configurações de cadeias de suprimentos propostas por Holmström et al (2003), o que permite medir o desempenho da cadeia de suprimentos segundo 3 níveis de integração. É feita uma revisão bibliográfica dos conceitos da estratégia de VMI, políticas de estoque em sistemas integrados, compartilhamento e grau de visibilidade de informações ao longo da cadeia de suprimentos. Os resultados obtidos possibilitam realizar uma análise quantitativa dos benefícios do VMI, onde são considerados demanda estocástica, lead time aleatório, produtos com características diferentes, compartilhamento de informações, visibilidade parcial da cadeia de suprimentos, lotes variáveis, cálculo dos estoques de segurança considerando informações dos pedidos, demanda real do cliente e erros de previsão. / In this paper we proposed a simulation model of an integrated supply chain with the adoption of VMI (Vendor Managed Inventory) strategy between a company of the iron ore and some of its strategic suppliers. The model is based on a framework for evaluating VMI systems adapted from Sarpola et al. (2007) together with the configurations of supply chains proposed by Holmström et al (2003), which measures the performance of the supply chain using 3 levels of integration. It is a literature review of the concepts of the strategy of VMI, inventory policies in integrated systems, sharing and degree of visibility of information throughout the supply chain. The results allowed to perform a quantitative analysis of the benefits of VMI, which are considered as stochastic demand, random lead time, products with different characteristics, information sharing, partial visibility of the supply chain, lots of variables, calculation of safety stocks based on information from client orders, actual customer demand and forecasting errors.