Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 69-71). Also available via the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / There are no leaves 76-78; manuscript misnumbered between 75 and 79. Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / There are no leaves 76-78; manuscript misnumbered between 75 and 79. Typescript. Vita. Includes bibliographical references. Also available on the Internet.

The overall goal of this work is to create an open-source digital twin of the wire arc directed energy deposition process using robot operating system 2 for interpass temperature regulation of a maraging steel alloy. This framework takes a novel approach to regulating the interpass temperatures by using in-situational infrared camera data and a closed loop feedback control that is enabled by robot operating system 2. This is the first implementation of robot operating system 2 for wire arc directed energy deposition and this framework outlines a sensor and machine agnostic approach for creating a digital twin of this additive manufacturing process. In-situ control of the welding process is conducted on a maraging steel alloy demonstrating interpass temperature regulation leads to improved as-built surface roughness and more consistent as-built hardness. An evaluation of three distinct weld modes: Pulsed MIG, CMT MIX, and CMT Universal and two primary process parameters: travel speed and wire feed speed was conducted to identify suitable process windows for welding the maraging alloy. Single track welds for each parameter and weld mode combination were produced and evaluated against current weld bead metrics in the literature. Non destructive profilometry and destructive characterization were performed on the single track welds to evaluate geometric features like wetting angle, dilution percentage, and cross sectional area. In addition, the role of material feed rate on heat input and the cross sectional area was examined in relation to the as-built hardness. The robot operating system 2 digital twin provides a visualization environment to monitor and record real time data from a variety of sensors including robot position, weld data, and thermal camera images. Point cloud data is visualized, in real time, to provide insight to the captured weld meta data. Capturing in-situ data from the wire arc directed energy deposition process is critical to establishing an improved understanding of the process for parameter optimization, tool path planning, with both required to build repeatable, quality components. This work presents an open-source method to capture multi-modal data into a shared environment for improved data capture, data sharing, data synchronization, and data visualization. This digital twin provides users enhanced process control capabilities and greater flexibility by utilizing the robot operating system 2 as a middleware to provide interoperability between sensors and machines.

Dissertation (Ph.D.)--University of South Florida, 2006. / Title from PDF of title page. Document formatted into pages; contains 107 pages. Includes vita. Includes bibliographical references.

The thesis deals with formation of a workplace for preparation gaseous mixtures and their future usage. The main goal of the thesis is testing of new materials which have suitable usage as catalysts. Gaseous mixture is prepared by calorimetric mass flow meters with control valve and multiposition microelectric valve actuators. The next part describes measuring of pressure and temperature and controlling of furnace temperature. The thesis deals with specifications of all devices, their circuitry, communication and program controlling. All devices are controlled by computer with program which is programmed in LabVIEW.

Orientador: Carlos Alberto Carrasco Altemani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-06T09:32:44Z (GMT). No. of bitstreams: 1 Souza_ValterCesarde_D.pdf: 4532174 bytes, checksum: 07cf885bb91505cb080fc4a067621191 (MD5) Previous issue date: 2005 / Resumo: Os dissipadores térmicos de placas paralelas com entrada de topo e saída lateral constituem uma alternativa para intensificar a remoção da potência elétrica dissipada em microprocessadores. Neste trabalho, três dissipadores térmicos de placas paralelas foram construídos e testados com escoamento variável de ar sob condições de entrada de topo e saída lateral. Os resultados experimentais foram comparados com correlações da literatura e com resultados de simulações numéricas tridimensionais. Após a validação com os resultados experimentais, o modelo numérico foi utilizado num procedimento para obter o número de aletas do dissipador para a máxima troca térmica convectiva. Dois casos foram considerados, um deles baseado numa velocidade média do ar constante na entrada do dissipador, e o outro, numa relação linear da curva de operação de um ventilador / Abstract: The parallel plates heat sinks with top inlet and side exit constitute an enhanced heat transfer alternative for the local removal of electric power dissipation in microprocessors. In the present work, three parallel plates heat sinks were built and tested with variable airflow under the conditions of top inlet and side exit. The experimental results were compared with correlations from the literature and with results from three-dimensional numerical simulations. After the validation with the experimental results, the numeric model was used in an optimization procedure to obtain the heat sink number of fins for the maximum convective heat transfer. Two cases were considered, one based on a constant average inlet air velocity, and the other, on an assumed linear fan curve / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica

This thesis deals with DCS for bulding control. The main aim was to develop a general system, which can be adapted according to the individual requirements and which should minimize costs too. Hardware modules, communication bus, communication protocol, system topology and regulation mechanisms, have been designed. Regulators have been set. There are introduced current realization and possible future extensions too. The high security and the high functionality topics are included.

I samarbete med Norconsult och kund ska denna rapport undersöka inomhusklimatet i ett museum och resultera i ett förslag på ett kontrollsystem för Heating, Vetilation and Air conditioning (HVAC) som genererar stabil temperatur och relativ luftfuktighet (RF) inom rekommenderade gränsvärden för konstbevaring. Genom litteraturstudier, fältstudier, dataanalys och skapandet av en simulerad modell av utrymmet, ska ett förslag om lämplig kontrollmetod av HVAC framläggas. Vid test av olika kontrollmetoder, tog sig MPC-kontrollen sig bäst ut. Litteraturstudien innefattar flera studier och rapporter som använt sig av MPC-kontroll för liknande projekt med fördelaktiga resultat. Resultaten av dataanalysen visar att under stor del av loggnings-perioden avvek temperatur och/eller RF från gränsvärdena. I vissa utrymmen var uppemot 99% av de loggade värdena utanför gränsvärdet för antingen temperatur eller RF. Av samtliga sensorsamplingar på museet låg 48,53% av dessa utanför de satta rekommendationerna. Generellt var luften i museet för varm och torr till syftet konstförvaltning. Vid jämförelse av de tre utvecklade MPC-kontrollerna, visar alla varianterna till att generera stabila resultat. Det framarbetade förslaget indikerar på ett energieffektivare kontrollsystem gentemot befintligt. Om simuleringsmodellen av utrymmet visar skilja sig från verkliga förhållanden, förändras dynamiken i systemet, och inställningarna för MPC-kontrollen gäller ej längre utan behövs konfigureras om. Projektets primära mål om att generera ett optimerat systemförslag som kontrollerar parametrarna temperatur RF, anses ha uppnåtts - om än endast i simulerade resultat. Vidare arbete innefattar att verifiera modellen mot befintligt system, och därefter inkludera kostnadsfunktioner till MPC-kontrollen. Efter systemimplementering bör faktiska utfall jämföras med simulerade utfall för att utvärdera modellens precision. / In collaboration with Norconsult and the customer, this report will examine the indoor climate in the museum and result in a proposal for a control system for HVAC that generates stable temperature and RH within recommended values ​​for the preservation of art. A proposal for an appropriate control method of the HVAC shall be presented through literature studies, field studies, data analysis, and the creation of a simulated model of the environment. The MPC control performed best during the testing of different control methods. The literature study includes several studies and papers that use MPC control for similar projects with beneficial results. The results of the data analysis show that during a large part of the logging period, the temperature and/or RH deviated from the limit values. In some areas, up to 99% of the logged values ​​were outside recommendations. Of all sensor samplings at the museum, 48.53% of these were registered outside limit values. In general, the air in the museum was too hot and dry for art preservation. When comparing the three developed MPC controllers, all variants show to generate stable results. The elaborated proposal indicates a more energy-efficient control system compared to the existing one. If the simulation model of the environment turns out to differ from real conditions, the dynamics of the system change , and the settings for the MPC control no longer apply and need to be reconfigured. The project's primary goal of generating an optimized system proposal that controls the temperature and relative humidity is considered to have been achieved - albeit only in simulated results. Further work includes verifying the model against the existing system and including cost functions to the MPC control. After system implementation, actual outcomes should be compared with simulated outcomes to evaluate model precision.

This thesis presents work on a holistic approach for improving the overall design of solar cooling systems driven by solar thermal collectors. Newly developed methods for thermodynamic optimization of hydraulics and control were used to redesign an existing pilot plant. Measurements taken from the newly developed system show an 81% increase of the Solar Cooling Efficiency (SCEth) factor compared to the original pilot system. In addition to the improvements in system design, new efficiency factors for benchmarking solar cooling systems are presented. The Solar Supply Efficiency (SSEth) factor provides a means of quantifying the quality of solar thermal charging systems relative to the usable heat to drive the sorption process. The product of the SSEth with the already established COPth of the chiller, leads to the SCEth factor which, for the first time, provides a clear and concise benchmarking method for the overall design of solar cooling systems. Furthermore, the definition of a coefficient of performance, including irreversibilities from energy conversion (COPcon), enables a direct comparison of compression and sorption chiller technology. This new performance metric is applicable to all low-temperature heat-supply machines for direct comparison of different types or technologies. The achieved findings of this work led to an optimized generic design for solar cooling systems, which was successfully transferred to the market.