Spelling suggestions: "subject:"are reduction""
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Design of a cross section reduction extrusion tool for square barsOnipede, Bolarinwa O. 25 April 2007 (has links)
The objective of this project is to design a tool for moderate cross section reduction of
bars that are deformed within a channel slider tool that is used for equal channel angular
extrusion (ECAE). The bars that are deformed via ECAE have an initial square cross
section with a nominal value of 1.00 in2 and aspect ratios (length/width) ranging
between 4 and 6. A systems engineering design methodology is used to generate a topbottom
approach in the development of the tool's design. This includes defining a need
statement, which is the "Need for an area reduction extrusion tool to replace the current
practices of machining ECAE processed billets". The system functions and requirements
are defined next and used to generate three concepts that are compared to select the
winning concept for further refinement. Major components of the selected tool are: a
container, ram, base plate, punch plate, four die-inserts, four wedges and four flange
locks. For materials, such as copper (C10100) and aluminum (Al6061-T6), that can be
processed by this tool, the upper bound extrusion pressure, which is derived by limit
analysis, is set at 192 ksi. The upper bound extrusion pressure is constrained by the
buckling limit of the ram, which is 202 ksi. The maximum wall stress experienced by the
container is 113 ksi. For materials with the same cross section and dimensions, fixed end
conditions of the Ram support larger bucking loads when compared to other end
conditions such as rounded ends or rounded-fixed ends. With the application of the
upper bound method, an increase in the extrusion ratio of the tool causes a corresponding
rise in the optimal cone angle of the die further translating to a rise in the extrusion
pressure.
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Improvement of sampling system for Remote Explosive Scent TracingUddqvist, Anette, Roberthson, Ida January 2010 (has links)
Remote Explosives Scent Tracing (REST) is the concept of bringing the mine field to Mine Detection Dogs or Rats, instead of vice versa. This is done by collecting air or dust from minefields, and taking these samples to a laboratory environment, where they are subsequently analysed by the detection animals. REST has previously proven to be very fast and cost effective, but one of the issues facing the method is that there is yet no reliable tool for sampling dust. In earlier sampling units, air has been collected in filters. However, the concentration of scents related to mines has been seen to be a million times higher in dust particles than in air sampled from above the ground. The aim of this project was to evaluate and improve a dust sampling prototype constructed in the beginning of 2010. The project was initiated in cooperation with the GICHD (Geneva International Centre for Humanitarian demining), and carried out in cooperation with APOPO (Anti-Personnel Landmines Detection Product Development). During this project, information was gathered on the samplers that have previously been used for REST. A new prototype was made in Trondheim in cooperation with NTNU (Norwegian University of Science and Technology). With this new sampler prototype, tests were made in a laboratory environment at NTNU as well as at APOPO’s test mine field in Morogoro, Tanzania. Several obstacles were faced, such as difficulties to test and evaluate the sampler during the rainy season, insufficient air supply for the prototype, and issues with the laboratory equipment in Morogoro. Due to this, the number of tests performed and the number of repetitions of each test was not as high as would have been desired. The results of the information gathering and the tests are presented in this report, and the knowledge and experience gained resulted in several suggestions for improvements for the sampler prototype. A suggestion for a grid design that would cover the entire mouth piece, with a built-in distance to the suction inlet, in order to avoid both clogging of the grid and that too much dust is sucked in if the mouth piece touches the ground and a fully adjustable sampling unit. Several other recommendations are given that would reduce cross contamination risks and improve ergonomics and other aspects of the sampler prototype.
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Improvement of sampling system for Remote Explosive Scent TracingUddqvist, Anette, Roberthson, Ida January 2010 (has links)
<p>Remote Explosives Scent Tracing (REST) is the concept of bringing the mine field to Mine Detection Dogs or Rats, instead of vice versa. This is done by collecting air or dust from minefields, and taking these samples to a laboratory environment, where they are subsequently analysed by the detection animals.</p><p>REST has previously proven to be very fast and cost effective, but one of the issues facing the method is that there is yet no reliable tool for sampling dust. In earlier sampling units, air has been collected in filters. However, the concentration of scents related to mines has been seen to be a million times higher in dust particles than in air sampled from above the ground. The aim of this project was to evaluate and improve a dust sampling prototype constructed in the beginning of 2010. The project was initiated in cooperation with the GICHD (Geneva International Centre for Humanitarian demining), and carried out in cooperation with APOPO (Anti-Personnel Landmines Detection Product Development).</p><p>During this project, information was gathered on the samplers that have previously been used for REST. A new prototype was made in Trondheim in cooperation with NTNU (Norwegian University of Science and Technology). With this new sampler prototype, tests were made in a laboratory environment at NTNU as well as at APOPO’s test mine field in Morogoro, Tanzania. Several obstacles were faced, such as difficulties to test and evaluate the sampler during the rainy season, insufficient air supply for the prototype, and issues with the laboratory equipment in Morogoro. Due to this, the number of tests performed and the number of repetitions of each test was not as high as would have been desired.</p><p>The results of the information gathering and the tests are presented in this report, and the knowledge and experience gained resulted in several suggestions for improvements for the sampler prototype. A suggestion for a grid design that would cover the entire mouth piece, with a built-in distance to the suction inlet, in order to avoid both clogging of the grid and that too much dust is sucked in if the mouth piece touches the ground and a fully adjustable sampling unit. Several other recommendations are given that would reduce cross contamination risks and improve ergonomics and other aspects of the sampler prototype.</p>
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Area Efficient Multi-Ported Memories with Write Conflict ResolutionMuddebihal, Akshata 13 October 2014 (has links)
No description available.
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The use of higher steel grades in building elementsBerggren, Hampus January 2021 (has links)
Structural steel is one of the main building materials used commercial. Its strength is its formality and high yield strength which allows less material overall. Steel is often divided into steel grades such as S275, S355, S420 and so forth. The purpose of this thesis is to look at the strength and weaknesses of the different steel grades and how the area gets effected by higher steel grades. This is done by looking at a real life project where only S355 is used and optimizing for S355, S420 and S460. This is done to shred some light on how much of an improvement the upgrade of steel grade may allow. For each steel grade an optimized cross section is created with the goal of having the lowest area possible. The difference in area for the optimized beams will act as the benchmarking for projected reductions. This optimization is done with the help of Python and follows Eurocode. When looking at the case study, the projected weight reduction is 4,2% for S420 and 7,2% for S460 compared to S355. This reduction is higher on some beams and lower on others. The main driving force for the higher reduced beams is the possibility to utilize more than one type of load condition, example both momentand shear force. Out of the 12 beams, beam 10 have the highest reduction between S355 and S420 which land around 10%. Between S355 and S460 Beam 12 comesin at a area reduction of 14%. As the higher steel grades have a higher equivalent CO2 emission the reduction of equivalent CO2 is lower than the area reduction. The projected reduction of equivalent CO2 for a switch from S355 to S420 is 3,3% and the reduction between S355 and S460 are 5,0%
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Análise comparativa do efeito da distribuição espaço-tempo em eventos pluviométricos intensos na formação de vazões em bacias urbanas. / Comparative analysis of the effect of space-time distribution of heavy rainfall events in the formation of flows in urban catchments.Girnius, Lígia de Souza 18 May 2016 (has links)
Esta pesquisa tem como finalidade discutir os impactos da variabilidade espacial e temporal de precipitações intensas nas vazões de cursos d\'água em bacias urbanizadas mediante a análise de dados históricos da pluviometria obtidos durante eventos críticos. A bacia hidrográfica do rio Tietê, em sua porção mais urbanizada, é a área objeto deste estudo. Após uma revisão sobre o tema na literatura específica, foram desenvolvidas chuvas de projeto com os padrões observados e com padrões teóricos, frequentemente utilizados na geração das tormentas sintéticas. O volume total precipitado foi associado ao período de retorno (TR) de 100 anos, a partir da análise estatística de chuvas pontuais e pela aplicação de fatores de redução de área (FRA) observados na área em estudo e de outras regiões, que vêm sendo utilizados em projetos de drenagem, sem qualquer estudo de validação; o intuito foi o de demonstrar a importância da definição de FRA específicos, a fim de evitar superdimensionamentos e otimizar as soluções. As chuvas de projeto foram aplicadas num modelo matemático de transformação chuva-vazão, devidamente calibrado, para obtenção das vazões de projeto resultantes no limite de jusante da bacia hidrográfica, frente aos diferentes padrões de solicitações hidrológicas. Para auxiliar a calibração do modelo estavam disponíveis dados dos postos telemétricos do Sistema de Alerta a Inundações de São Paulo - SAISP, curvas-chave e, para melhor representação dos eventos de precipitação observados, pode-se contar com as imagens do radar de Ponte Nova, em complementação às informações da rede de superfície. A comparação dos resultados obtidos no modelo hidrológico mostrou que os efeitos dos parâmetros variáveis (volume, distribuição espacial e temporal) são expressivos na composição dos hidrogramas de projeto. Dos testes realizados, identificaram-se as situações mais e menos críticas para a bacia, em termos de distribuição espacial e temporal e duração da chuva de projeto, além de estabelecer as diferenças no dimensionamento do sistema de drenagem pela adoção de FRA específico. Concluiu-se que, pela metodologia proposta, é possível chegar a vazões máximas de projeto apenas pela simulação de tormentas sintéticas, com diferenças de 10% a 20% das tormentas observadas maximizadas. Há, no entanto, a necessidade de realização de estudos adicionais, tanto para definição dos valores de FRA específicos, quanto de simulação de quantidade maior de padrões críticos observados, para a aplicação prática das indicações desse estudo com maior confiabilidade. / This research aims to discuss the impact of the spatial and temporal variability of heavy rainfall in the river flows in urbanized catchments by the historical rainfall data analysis obtained during critical events. The Tiete River catchment, in its most urbanized portion, is the subject of study of this research. After a review of the subject in the specific literature, design rainfall was developed along with the observed and theoretical patterns, often used in the generation of synthetic storms. The total volume precipitated was associated with the 100 years return period (RP), from the statistical analysis of point rainfall and for the application of areal reduction factors (ARF) observed in the study area and in other regions, which have been used in drainage projects without any validation study; the intention was to demonstrate the importance of the definition of specific ARF, in order to avoid oversizing and optimizing solutions. The design precipitation was applied on rainfall-runoff mathematical model, properly calibrated, so as to obtain the resulting design flow at the downstream boundary of the catchment, facing the different patterns of hydrological solicitations. In order to assist the calibration of the model, available data has been used from telemetric stations of the Sistema de Alerta a Inundações de São Paulo (São Paulo Flooding Alert System) - SAISP, discharge curves, and for better representation of the observed precipitation events, can be counted on the images taken from the Ponte Nova radar, as a complement to the information from the surface network. The comparison of the results of the hydrological model has shown that the effects of the variable parameters (volume, spatial and temporal distributions) are significant in the composition of the design hydrograph. Out of the performed tests, the most and the least critical situations were identified concerning the catchment in terms of both spatial and temporal distribution as well as the duration of the design storm. Also, the differences in the dimensions of the of the drainage system design were established by the adoption of specific ARF. Thus, it has been concluded, according to the proposed methodology, that it is possible to reach maximum design flow just by simulating synthetic storms, with differences ranging from 10% to 20% of the observed storms maximized. However, there is a need for additional studies, either to set up setting specific values of ARF or to simulate a larger quantity of critical patterns observed, in order to apply the indications of this study with higher reliability.
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Análise comparativa do efeito da distribuição espaço-tempo em eventos pluviométricos intensos na formação de vazões em bacias urbanas. / Comparative analysis of the effect of space-time distribution of heavy rainfall events in the formation of flows in urban catchments.Lígia de Souza Girnius 18 May 2016 (has links)
Esta pesquisa tem como finalidade discutir os impactos da variabilidade espacial e temporal de precipitações intensas nas vazões de cursos d\'água em bacias urbanizadas mediante a análise de dados históricos da pluviometria obtidos durante eventos críticos. A bacia hidrográfica do rio Tietê, em sua porção mais urbanizada, é a área objeto deste estudo. Após uma revisão sobre o tema na literatura específica, foram desenvolvidas chuvas de projeto com os padrões observados e com padrões teóricos, frequentemente utilizados na geração das tormentas sintéticas. O volume total precipitado foi associado ao período de retorno (TR) de 100 anos, a partir da análise estatística de chuvas pontuais e pela aplicação de fatores de redução de área (FRA) observados na área em estudo e de outras regiões, que vêm sendo utilizados em projetos de drenagem, sem qualquer estudo de validação; o intuito foi o de demonstrar a importância da definição de FRA específicos, a fim de evitar superdimensionamentos e otimizar as soluções. As chuvas de projeto foram aplicadas num modelo matemático de transformação chuva-vazão, devidamente calibrado, para obtenção das vazões de projeto resultantes no limite de jusante da bacia hidrográfica, frente aos diferentes padrões de solicitações hidrológicas. Para auxiliar a calibração do modelo estavam disponíveis dados dos postos telemétricos do Sistema de Alerta a Inundações de São Paulo - SAISP, curvas-chave e, para melhor representação dos eventos de precipitação observados, pode-se contar com as imagens do radar de Ponte Nova, em complementação às informações da rede de superfície. A comparação dos resultados obtidos no modelo hidrológico mostrou que os efeitos dos parâmetros variáveis (volume, distribuição espacial e temporal) são expressivos na composição dos hidrogramas de projeto. Dos testes realizados, identificaram-se as situações mais e menos críticas para a bacia, em termos de distribuição espacial e temporal e duração da chuva de projeto, além de estabelecer as diferenças no dimensionamento do sistema de drenagem pela adoção de FRA específico. Concluiu-se que, pela metodologia proposta, é possível chegar a vazões máximas de projeto apenas pela simulação de tormentas sintéticas, com diferenças de 10% a 20% das tormentas observadas maximizadas. Há, no entanto, a necessidade de realização de estudos adicionais, tanto para definição dos valores de FRA específicos, quanto de simulação de quantidade maior de padrões críticos observados, para a aplicação prática das indicações desse estudo com maior confiabilidade. / This research aims to discuss the impact of the spatial and temporal variability of heavy rainfall in the river flows in urbanized catchments by the historical rainfall data analysis obtained during critical events. The Tiete River catchment, in its most urbanized portion, is the subject of study of this research. After a review of the subject in the specific literature, design rainfall was developed along with the observed and theoretical patterns, often used in the generation of synthetic storms. The total volume precipitated was associated with the 100 years return period (RP), from the statistical analysis of point rainfall and for the application of areal reduction factors (ARF) observed in the study area and in other regions, which have been used in drainage projects without any validation study; the intention was to demonstrate the importance of the definition of specific ARF, in order to avoid oversizing and optimizing solutions. The design precipitation was applied on rainfall-runoff mathematical model, properly calibrated, so as to obtain the resulting design flow at the downstream boundary of the catchment, facing the different patterns of hydrological solicitations. In order to assist the calibration of the model, available data has been used from telemetric stations of the Sistema de Alerta a Inundações de São Paulo (São Paulo Flooding Alert System) - SAISP, discharge curves, and for better representation of the observed precipitation events, can be counted on the images taken from the Ponte Nova radar, as a complement to the information from the surface network. The comparison of the results of the hydrological model has shown that the effects of the variable parameters (volume, spatial and temporal distributions) are significant in the composition of the design hydrograph. Out of the performed tests, the most and the least critical situations were identified concerning the catchment in terms of both spatial and temporal distribution as well as the duration of the design storm. Also, the differences in the dimensions of the of the drainage system design were established by the adoption of specific ARF. Thus, it has been concluded, according to the proposed methodology, that it is possible to reach maximum design flow just by simulating synthetic storms, with differences ranging from 10% to 20% of the observed storms maximized. However, there is a need for additional studies, either to set up setting specific values of ARF or to simulate a larger quantity of critical patterns observed, in order to apply the indications of this study with higher reliability.
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A Fully Analog Motion Artifacts and Baseline Wander Elimination Circuit for Ambulatory ECG Recording SystemsNazari, Masoud 01 May 2023 (has links)
No description available.
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