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An Empirical Analysis of Publicity and Advertising under Quality UncertaintyLim, Hyunwoo 17 December 2012 (has links)
Quality of a prescription drug is uncertain to patients, physicians and even the manufacturer of the drug. Because this uncertainty can deter physicians from prescribing the drug, it is important to investigate how various marketing communication activities help reveal the true quality of its product. In particular, this study investigates publicity and advertising under quality uncertainty. Chapter 1 studies the effect of publicity on consumer demand with a reduced form approach. Chapter 2 structurally investigates the roles of detailing and publicity when the information spill-over is present. Both chapters study the market of anti-cholesterol drugs (statins).
Chapter 1 investigates the effects of publicity (media coverage) on consumer demand. The main obstacle to measuring the impact of publicity is that data on media coverage are difficult to interpret. To overcome this obstacle, we propose a new way to code information presented in news articles, mapping the information to a multi-dimensional attribute space. We combine our publicity data with data on sales, detailing, medical journal advertising, direct-to-consumer advertising (DTCA) and landmark clinical trial outcomes, and estimate a demand model. Our results suggest that not all forms of publicity are equal.
In chapter 2, we study consumer learning about scientific evidence and its impact on demand for pharmaceutical products by using the Bayesian learning model. Unlike previous literature, our learning model allows consumer’s prior quality perceptions to be correlated across brands. This unique feature of the model allows us to investigate information spill-over effects across brands. The information spill-over allows late entrants to free-ride on first movers’ investment in clinical trials and marketing activities and to gain late mover advantage. In addition to using product level market share data, we supplement them with switching rates and discontinuing rates. The switching rate data are particularly useful for taking the presence of switching costs into consideration, which has been ignored in the literature using product-level data. Our estimated structural model has implications for managers in allocating resources to various types of marketing activities more efficiently and helps forecast returns of clinical trials that are sponsored by pharmaceutical firms.
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Diretrizes para o dimensionamento e detalhamento de pilares de edifícios em concreto armado / Directions for design and detail of columns in reinforced concrete buildingsFábio Augusto Aufieri 21 October 1997 (has links)
Este trabalho tem o objetivo de transmitir aos Engenheiros de Estruturas o conhecimento teórico necessário para o dimensionamento e detalhamento de pilares usuais de edifícios em concreto armado. A definição das posições dos pilares em uma estrutura, bem como uma estimativa da seção transversal dos mesmos são abordadas neste trabalho. O estudo da estabilidade global, realizado no Capítulo 3, nos permite avaliar se os deslocamentos ocorridos na estrutura em função das ações horizontais e verticais, geram esforços de segunda ordem consideráveis ou não. A instabilidade de pilares será comentada no Capítulo 5, bem como os Métodos desenvolvidos para avaliar se um determinado pilar é estável ou instável. O detalhamento de pilares segundo as prescrições do Texto Base para a revisão da NBR - 6118/78, bem como o desenvolvimento de exemplos de dimensionamento de pilares estão contidos neste trabalho nos Capítulos 7 e 8, respectivamente. / The objective of this work is to transrnit to the structural engineers the necessary theoretical knowledge for the design and detail of usual columns in reinforced concrete buildings. The definition of the columns positions in the structure, as well as an estimate of their cross section will be explained in this work. The global stability study, described in chapter 3, allows us to evaluate whether the deformations ocurred in the structure due to horizontal and vertical actions, cause considerable second order strength or not. The columns instability will be commented in chapter 5, as well as the methods developed to evaluate whether a specific column is stable or instable. The columns detail as prescribed in the Basic Text for the Revision of NBR - 6118/78, and also the development of examples for columns design are in chapter 7 and 8, respectively.
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Arranjos de armaduras para estruturas de concreto armado / Reinforcements arranges in reinforced concrete structuresEliane Fiorin 18 March 1998 (has links)
A disposição das armaduras nos elementos estruturais não influencia somente o comportamento do elemento estrutural, mas também a facilidade e viabilidade da sua execução na obra. O detalhamento do arranjo de armadura está diretamente ligado com a segurança da construção. Os textos que existem sobre técnica de armar se encontram dispersos, dificultando o acesso dos profissionais e estudantes de engenharia de estruturas. Este trabalho analisa os vários arranjos de armaduras propostos para lajes maciças e nervuradas, vigas e pilares procurando indicar o mais adequado de acordo com os critérios de economia, facilidade de execução e comportamento do elemento estrutural, quando possível. Para melhor ilustrar os arranjos de armaduras, é apresentado o dimensionamento de um edifício residencial de pequena altura, onde, podem ser observadas as rotinas de projeto adotadas, bem como os processos para o detalhamento das armaduras. Usaram-se o programa computacional elaborado por TQS Informática Ltda e também processo não computacional. Este programa para análise estrutural de edifícios apresenta boa interface com o usuário, proporcionando-lhe grande interesse e relativa facilidade de utilização. / The disposition of the reinforcement in the structural elements does not affect only the structural element behaviour, but also the facility and the viability of the building execution. The detailing of the reinforcement arrange is directly connected to the building safety. The existing texts about the technícs of reinforcing are spread in the literature of the structural engineering, making the access of the students and professionals to them difficult. The present work analyses the many different proposed arrangements of reinforcement for the slabs, joist floors, beams and columns, trying to indicate the most adequate one, according to the economic criteria, facility of execution, and the structural element behaviour, when possible. The design of a building of a short height is presented, as a way of better visualizing the reinforcement arrangements. In that example the adopted project routines could be observed, as well as the process of detailing the reinforcements. To reach this purpose, a software designed by TQS Informática Ltda was used, as well as a non-computer process. This software for the structural analysis of building presents a good interface with the users, providing them with great interest and relative facility of use.
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Performance of High-Strength Reinforced Concrete Columns Under Shock-Tube Induced Blast LoadingHammoud, Amer January 2017 (has links)
Accounting for blast hazards has become one of the major concerns for civil engineers when analysing and designing structures. Recent terrorist attacks and accidental explosions have demonstrated the importance of mitigating blast effects on buildings to ensure safety, preserve life and ensure structural integrity. Innovative materials such as high-strength concrete, steel fibers, and high-strength steel offer a potential solution to increase resistance against extreme dynamic loading and improve the blast resilience of buildings. This thesis presents the results of an experimental and analytical study examining the effect of high-strength concrete, high-strength reinforcement and steel fibers on the blast behaviour of reinforced concrete columns.
As part of the study, a total of seventeen reinforced concrete columns with different design combinations of concrete, steel fibers, and steel reinforcement were designed, constructed, and tested under gradually increasing blast loads using the University of Ottawa shock-tube facility. Criteria used to assess the blast performance of the columns and the effect of the test variables included overall blast capacity, mid-span displacements, cracking patterns, secondary fragmentation, and failure modes. The effect of concrete strength was found to only have a moderate effect on the blast performance of the columns. However, the results showed that benefits are associated with the combined use of high-strength concrete with steel fibers and high-strength reinforcement in columns tested under blast loads. In addition to the experimental program, a dynamic inelastic single-degree-of-freedom analysis was performed to predict the displacement response of the test columns. A sensitivity analysis was also conducted to examine the effect of various modelling parameters such as materials models, DIFs, and accumulated damage on the analytical predictions.
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Comprehending Performance of Cross-Frames in Skewed Straight Steel I-Girder BridgesGull, Jawad H 20 February 2014 (has links)
The effects of support in steel bridges can present significant challenges during the construction. The tendency of girders to twist or layovers during the construction can present a particularly challenging problem regarding detailing cross-frames that provide bracing to steel girders. Methods of detailing cross-frames have been investigated in the past to identify some of the issues related to the behavior of straight and skewed steel bridges. However, the absence of a complete and simplified design approach has led to disputes between stakeholders, costly repairs and delays in the construction.
The main objective of this research is to develop a complete and simplified design approach considering construction, fabrication and detailing of skewed bridges. This objective is achieved by comparing different detailing methods, understanding the mechanism by which skew effects develop in steel bridges, recommending simplified methods of analysis to evaluate them, and developing a complete and simplified design procedure for skew bridges.
Girder layovers, flange lateral bending stress, cross-frame forces, component of vertical deflections, component of vertical reactions and lateral reactions or lateral displacements are affected by detailing methods and are referred as lack-of-fit effects. The main conclusion of this research is that lack-of-fit effects for the Final Fit detailing method at the steel dead load stage are equal and opposite to the lack-of-fit effects for the Erected Fit detailing method at the total dead load stage. This conclusion has helped using 2D grid analyses for estimating these lack-of-fit effects for different detailing methods.
3D erection simulations are developed for estimating fit-up forces required to attach the cross-frames to girders. The maximum fit-up force estimated from the 2D grid analysis shows a reasonable agreement with the one obtained from the erection simulations. The erection sequence that reduces the maximum fit-up force is also found by erection simulations.
The line girder analysis is recommended for calculating cambers for the Final Fit detailing method. A combination of line girder analysis and 2D grid analysis is recommended for calculating cambers for the Erected Fit detailing method. Finally, flowcharts are developed that facilitate the selection of a detailing method and show the necessary design checks.
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Effects of Detailing and Fibers on the Static and Blast Behaviour of High‐Strength Concrete BeamsCharles, Charlemagne Junior 18 December 2019 (has links)
The CSA S850 Blast standard provides guidelines that can be used to enhance the blast performance of reinforced concrete structures. In the case of beams, the standard requires the use of top continuity (compression) bars and well-detailed transverse steel to ensure strength and ductility under blast loads. However, the requirements in the CSA S850 standard are intended for normal-strength concrete structures. Given the increased use of high-strength concrete (HSC) in practice, there is a need to explore the effects of modern blast designs on the behavior of HSC structures subjected to blast loads.
Accordingly, this project examines the effect of modern reinforcement detailing on the static, dynamic and post-blast performance of high-strength concrete beams. The study further examines the ability to use fibers to relax such detailing and simplify construction. A total of seventeen beams are tested. Static testing is conducted under four-point bending, with blast testing conducted using the University of Ottawa shock-tube. The post-blast behavior of the beams is assessed by conducting residual static tests on the blast-damaged specimens. The parameters investigated include the effects of: blast detailing vs. nominal detailing, steel fibers, the effect of longitudinal steel ratio (in compression and tension) and tie spacing.
The results show that under static loads, the use of blast detailing significantly improves the flexural behavior of the beams in terms of ductility. Likewise, the provision of continuity (compression) bars and closely spaced ties is found to improve blast performance by better controlling displacements, increasing blast resistance, limiting damages and allowing for important post-blast residual capacity. The use of steel fibers and relaxed detailing (increased tie spacing) is found to increase resistance and improve cracking behavior under static loads, with an ability to match the blast performance of more heavily-detailed HSC specimens. The use of fibers also allowed for substantial post-blast capacity. Finally, the steel ratio (in tension, in compression and in the transverse direction) was found to affect the blast behavior of the HSC beams.
In addition to the experiments, the analytical study predicts the static and blast response of the tested beams using sectional analysis and non-linear SDOF modeling. Results show that the analysis methodology was able to predict the static and blast responses of the blast-detailed and fiber-reinforced HSC beams with reasonable accuracy.
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[pt] DETALHAMENTO DE SUPERFÍCIES UTILIZANDO TESSELAÇÃO EM HARDWARE / [en] SURFACE DETAILING USING HARDWARE TESSELLATION08 November 2021 (has links)
[pt] Técnicas de mapeamento de rugosidade são amplamente utilizadas para
simular detalhes estruturais de superfícies tridimensionais com o intuito de
aumentar a qualidade visual e compensar o baixo detalhamento geométrico
usualmente aplicado aos modelos enviados à GPU por questões de desempenho.
Avanços recentes no pipeline de renderização permitiram a geração massiva de
vértices no hardware gráfico através do recurso de tesselação, oferecendo aos
desenvolvedores uma poderosa ferramenta para controle do nível de detalhes de
objetos. Este trabalho apresenta uma técnica para o detalhamento geométrico de
modelos utilizando tesselação em hardware, baseada tanto em mapas précomputados
quanto em dados de deslocamento gerados inteiramente na GPU por
meio de técnicas de texturas procedimentais. Análises de desempenho e qualidade
visual demonstram as vantagens do método proposto em relação a uma técnica de
detalhamento baseada em imagens que é utilizada frequentemente em jogos
eletrônicos para enriquecimento da qualidade visual de seus ambientes. / [en] Bump mapping techniques are widely used to simulate structural details of
tridimensional surfaces in order to improve visual quality and compensate for the
low geometric detailing generally applied to models sent to the GPU due to
performance issues. Recent advances in the rendering pipeline enabled the
massive generation of vertex data in the graphics hardware by means of the
tessellation feature, providing developers with a powerful tool to control the
meshes’ level of details. The present work proposes a technique for geometric
detailing of models using hardware tessellation, both based on pre-computed
depth maps and on displacement data generated entirely on the GPU through
procedural textures techniques. Performance and visual quality analysis
demonstrates the advantages of the proposed method in relation to an image-based
technique commonly used in videogames for enhancing the visual quality of the
environments.
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Performance of Steel Fibre Reinforced Concrete Columns under Shock Tube Induced Shock Wave LoadingBurrell, Russell P. 19 November 2012 (has links)
It is important to ensure that vulnerable structures (federal and provincial offices, military structures, embassies, etc) are blast resistant to safeguard life and critical infrastructure. In the wake of recent malicious attacks and accidental explosions, it is becoming increasingly important to ensure that columns in structures are properly detailed to provide the ductility and continuity necessary to prevent progressive collapse. Research has shown that steel fibre reinforced concrete (SFRC) can enhance many of the properties of concrete, including improved post-cracking tensile capacity, enhanced shear resistance, and increased ductility. The enhanced properties of SFRC make it an ideal candidate for use in the blast resistant design of structures. There is limited research on the behaviour of SFRC under high strain rates, including impact and blast loading, and some of this data is conflicting, with some researchers showing that the additional ductility normally evident in SFRC is absent or reduced at high strain loading. On the other hand, other data indicates that SFRC can improve toughness and energy-absorption capacity under extreme loading conditions. This thesis presents the results of experimental research involving tests of scaled reinforced concrete columns exposed to shock wave induced impulsive loads using the University of Ottawa Shock Tube.
A total of 13 half-scale steel fibre reinforced concrete columns, 8 with normal strength steel fibre reinforced concrete (SFRC) and 5 with an ultra high performance fibre reinforced concrete (UHPFRC), were constructed and tested under simulated blast pressures. The columns were designed according to CSA A23.3 standards for both seismic and non-seismic regions, using various fibre amounts and types. Each column was exposed to similar shock wave loads in order to provide direct comparisons between seismic and non-seismically detailed columns, amount of steel fibres, type of steel fibres, and type of concrete.
The dynamic response of the columns tested in the experimental program is predicted by generating dynamic load-deformation resistance functions for SFRC and UHPFRC columns and using single degree of freedom dynamic analysis software, RCBlast. The analytical results are compared to experimental data, and shown to accurately predict the maximum mid-span displacements of the fibre reinforced concrete columns under shock wave loading.
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Performance of Steel Fibre Reinforced Concrete Columns under Shock Tube Induced Shock Wave LoadingBurrell, Russell P. 19 November 2012 (has links)
It is important to ensure that vulnerable structures (federal and provincial offices, military structures, embassies, etc) are blast resistant to safeguard life and critical infrastructure. In the wake of recent malicious attacks and accidental explosions, it is becoming increasingly important to ensure that columns in structures are properly detailed to provide the ductility and continuity necessary to prevent progressive collapse. Research has shown that steel fibre reinforced concrete (SFRC) can enhance many of the properties of concrete, including improved post-cracking tensile capacity, enhanced shear resistance, and increased ductility. The enhanced properties of SFRC make it an ideal candidate for use in the blast resistant design of structures. There is limited research on the behaviour of SFRC under high strain rates, including impact and blast loading, and some of this data is conflicting, with some researchers showing that the additional ductility normally evident in SFRC is absent or reduced at high strain loading. On the other hand, other data indicates that SFRC can improve toughness and energy-absorption capacity under extreme loading conditions. This thesis presents the results of experimental research involving tests of scaled reinforced concrete columns exposed to shock wave induced impulsive loads using the University of Ottawa Shock Tube.
A total of 13 half-scale steel fibre reinforced concrete columns, 8 with normal strength steel fibre reinforced concrete (SFRC) and 5 with an ultra high performance fibre reinforced concrete (UHPFRC), were constructed and tested under simulated blast pressures. The columns were designed according to CSA A23.3 standards for both seismic and non-seismic regions, using various fibre amounts and types. Each column was exposed to similar shock wave loads in order to provide direct comparisons between seismic and non-seismically detailed columns, amount of steel fibres, type of steel fibres, and type of concrete.
The dynamic response of the columns tested in the experimental program is predicted by generating dynamic load-deformation resistance functions for SFRC and UHPFRC columns and using single degree of freedom dynamic analysis software, RCBlast. The analytical results are compared to experimental data, and shown to accurately predict the maximum mid-span displacements of the fibre reinforced concrete columns under shock wave loading.
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A Web Based Multi-user Framework For The Design And Detailing Of Reinforced Concrete Frames-columnsUnal, Gokhan 01 December 2009 (has links) (PDF)
In design and detailing of a reinforced concrete frame project, there are many engineers who contribute a single project. Wide variety of information is exchanged between these engineers in design and detailing stages. If the coordination between engineers is not performed sufficiently, data exchange may result in loss of important information that may cause inadequate design and detailing of a structure. Thus, a data model developed for different stages of design and detailing of reinforced concrete structure can facilitate the data exchange among engineers and help improving the quality of structural design. In this study, an object oriented data model was developed for the design and detailing of reinforced concrete columns and beam column joints. The geometry of the structure, amount, shape and placement of reinforcement were defined in this data model. In addition to these, classes that facilitate the design and detailing of reinforced concrete columns and beam column joints according to a building codes were also developed. Another focus of this study is to develop a web based, platform independent data management and multi-user framework for structural design and detailing of reinforced concrete frames. The framework allows simultaneous design of a structure by multiple engineers. XML Web Services technology was utilized for the web based environment in such a way that the design related data was stored and managed centrally by the server in XML files. As a final step, CAD drawings of column reinforcement details in DXF format are prepared.
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