• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 8
  • 8
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

TELEMETRY AND COMMAND FRAME ROUTING IN A MULTI-MISSION ENVIRONMENT

Bester, Manfred, Stroozas, Brett 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In a modern ground control network for space communications, secure peer-to-peer TCP/IP network socket connections are typically used to transfer real-time telemetry and command frames between satellite operations centers and remote ground stations. Reliable and timely reconfiguration of data paths for upcoming pass supports becomes rather complex when many spacecraft and ground stations are involved. This paper describes a routing software application that was developed to facilitate switching of telemetry and command data paths between multiple ground stations and spacecraft command and control systems, and to forward telemetry streams to multiple client applications in parallel. Fully automated configuration and monitoring of the data flows is accomplished via a remote control interface that is tied into a pass scheduling system. The software is part of the SatTrack Suite and currently supports multi-mission flight operations, including those of the recently launched THEMIS constellation mission at Space Sciences Laboratory, University of California at Berkeley.
2

Expansion of perturbation theory applied to shim rotation automation of the Advanced Test Reactor

Peterson, Joshua Loren 19 October 2011 (has links)
In 2007, the Department of Energy (DOE) declared the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF). This declaration expanded the focus of the ATR to include diversified classes of academic and industrial experiments. An essential part of the new suite of more accurate and flexible codes being deployed to support the NSUF is their ability to predict reactor behavior at startup, particularly the position of the outer shim control cylinders (OSCC). The current method used for calculating the OSCC positions during a cycle startup utilizes a heuristic trial and error approach that is impractical with the computationally intensive reactor physics tools, such as NEWT. It is therefore desirable that shim rotation prediction for startup be automated. Shim rotation prediction with perturbation theory was chosen to be investigated as one method for use with startup calculation automation. A modified form of first order perturbation theory, called phase space interpolated perturbation theory, was developed to more accurately model shim rotation prediction. Shim rotation prediction is just one application for this new modified form of perturbation theory. Phase space interpolated perturbation theory can be used on any application where the range of change to the system is known a priori, but the magnitude of change is not known. A cubic regression method was also developed to automate shim rotation prediction by using only forward solutions to the transport equation. / text
3

Controle da injeção de catalisador em uma unidade piloto tipo FCC a frio.

Moura, Alex Elton de 31 August 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-04-15T15:07:33Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação CONTROLE DA INJEÇÃO DE CATALISADOR EM UMA UNIDADE PILOTO TIPO FCC A FRIO.pdf: 3413557 bytes, checksum: 5abbf7dd3a8cab8c21085e585d6282f6 (MD5) / Made available in DSpace on 2016-04-15T15:07:33Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação CONTROLE DA INJEÇÃO DE CATALISADOR EM UMA UNIDADE PILOTO TIPO FCC A FRIO.pdf: 3413557 bytes, checksum: 5abbf7dd3a8cab8c21085e585d6282f6 (MD5) Previous issue date: 2015-08-31 / CNPQ / O Craqueamento Catalítico Fluidizado (FCC) é largamente utilizado no processo de refino do petróleo para transformar hidrocarbonetos de baixo valor comercial em produtos de elevado valor agregado, como gasolina, diesel e GLP. A crescente demanda de combustíveis fósseis, que são recursos não renováveis, requer melhor compreensão do processo e da operação, desafios que tem atraído o interesse da indústria e da academia pelo FCC. Esse processo é bastante competitivo e está em continuo desenvolvimento tecnológico, cujas pesquisas estão divididas em duas grandes linhas: modelos fluidodinâmicos frios e modelos cinéticos. A combinação das informações obtidas nas linhas de pesquisas deve retornar ao processo industrial e garantir a competitividade. Com essa perspectiva, foi construída uma Unidade Piloto a Frio (UPF), no Departamento de Energia Nuclear da UFPE, para a investigação de parâmetros fluidodinâmicos no riser da unidade com auxílio das medidas de transmissão gama. A transmissão gama é requerida como método não intrusivo para medir a distribuição da concentração do catalisador no reator do FCC o riser. Com a operação da UPF realizam-se medidas em tempo real de pressão, vazão, intensidade da radiação, com a condição de que a automação garante que as variáveis do sistema estão sob controle. Este controle é necessário para realização das medidas porque as hipóteses dos modelos matemáticos para simular o escoamento bifásico ar–catalisador de FCC, assumem que o sistema é um leito fluidizado circulando em regime estacionário. Numa unidade piloto como no processo industrial, o controle da injeção de catalisador é um processo de extrema importância, pois a eficiência da reação de craqueamento dos hidrocarbonetos depende da concentração e da distribuição do catalisador no riser. No presente trabalho foi desenvolvido um novo tipo de injetor de sólidos, com desempenho avaliado em função da pressão, intensidade gama e da estabilidade do sistema sob controle automatizado. Os resultados apresentados demonstram que as variáveis do processo, medidas em tempo real, apresentaram a precisão requerida para a operação do sistema em regime estacionário. / The Fluid Catalyst Cracking FCC is a worldwide used process in petroleum refinery aiming to break fossils long carbohydrates chains into more commercial interesting products as gasoline, diesel, GLP. Increasing demand for renewable energy due to time limiting of the fossils sources and also for environmental reasons requires a continuous development and innovation of the FCC process. Such a demand brings technologic and academic efforts in order to keep FCC as a competitive commercial process. Therefore, the research follows two big lines: fluid dynamics and kinetic which for physical models are developed to simulate industrial plants for studying and return the obtained innovation. Looking for such a research perspective a cold model UPF was installed at Nuclear Energy Department of UFPE for fluid dynamic parameters investigation by means of gamma ray transmission measurements. The nuclear nonintrusive technique is required in the riser for the solid concentration distribution measurements. Online measurements of pressure, flow and gamma intensity are carried out during UPF automated operation that is keeping by control a stead state regime. Such operational conditions are assumed in the hypotheses of mathematical models that air-FCC catalyst flow can be simulated as a circulating fluidized bed in a stead state regime. As for a pilot unit in industrial plants the solid injection in riser is very important as the catalyst concentration distribution maps the cracking reactions, therefore, determining process efficiency. In this work a new solid injector was developed, its capability in keeping stable operational conditions was demonstrated by pressure and gamma intensity measurements under automation control.
4

Automatisk maskinåterställning : Hur automatiserade hjälpmedel kan bidra till en bättre produktion

Adolfsson, Jesper January 2021 (has links)
Ett vanligt förekommande problem med produktionsutrustning på Eberspächer är driftstopp där grundorsaken är svår att identifiera. Användning av sofistikerade system som isolerar felkällan kan minska avhjälpningstiden och därför vara till stor nytta för produktiviteten samt operatörens arbetsmiljö. Följande rapport undersöker möjligheterna kring att automatisera en återställning av en maskin fokuserad på mät- och kvalitetskontroll, till ett ursprungsläge där driftpersonal kan återuppta produktion efter ett driftstopp. Inledningsvis började arbetet med en litteraturstudie från vilket information inhämtades om de olika automatiserade delarna i mätcellen. Vidare studerades även maskinens PLC-program för att försöka förstå vad koden i de olika programmerade blocken gör. Programmeringen av den automatiserade återställningen gjordes i enighet med Eberspächers riktlinjer och kravspecifikation. Utifrån insamlad information om maskinens funktion har ett program med önskad funktionalitet kunnat skapas. Slutsatsen som kan dras av detta arbete är att det finns stora fördelar med att automatisera funktioner som kan vara svåra och kräva mycket av användaren. Den automatiserade återställningen är ett bra exempel på en funktion där det finns ekonomisk, ekologisk och ergonomisk vinning av att göra en komplicerad aktion lätthanterlig. / A common problem with production equipment at Eberspächer is downtime where the root cause is difficult to identify. The use of sophisticated systems that isolate the source of the error can reduce the remediation time and therefore be of great benefit to productivity. The following report examines how to automate the restoration of a machine focused on measurement and quality control, to an original mode where operating personnel can resume production after a downtime. Initially, work began on a literature study from which information was obtained about the various automated parts of the measuring cell. Furthermore, the machine's PLC program was also studied to try to understand what the code in the various programmed blocks does. The programming of the automated recovery was done in accordance with Eberspächer's guidelines and specification. Based on collected information about the machine's function, it has been possible to create a program with the desired functionality. The conclusion that can be drawn from this work is that there are great advantages to automating functions that can be difficult and require a lot of the user. The automated reset is a good example of a feature where there are economic, ecological and ergonomic benefits of making a complicated action manageable.
5

Python in der Regelungs- und Automatisierungstechnik

Knoll, Carsten 28 May 2024 (has links)
No description available.
6

Uma nova técnica para conservação de alimentos frescos baseada em instrumentação eletroeletrônica automatizada / A new technique for fresh food conservation based on automated electronics instrumentation

Lasso, Paulo Renato Orlandi 25 September 2003 (has links)
Neste trabalho é apresentado um sistema automatizado para armazenamento e conservação de alimentos vegetais frescos baseado em instrumentação eletroeletrônica e software de controle desenvolvido em LabView. Para a conservação, os produtos (já embalados) são armazenados imersos em uma solução aquosa preparada com água e um anticongelante como o etileno glicol (2%). Esta metodologia de armazenamento permite aumentar o tempo de prateleira através da redução da temperatura, sem o perigo de congelar os produtos armazenados. Os resultados mostram que a metodologia permite armazenar produtos frescos com segurança a apenas 0,4ºC acima do ponto de congelamento, enquanto que em câmaras convencionais esses devem ser armazenados a, pelo menos, 2,0ºC acima do ponto de congelamento. Essas condições proporcionam ao sistema de hidroconservação maior imunidade a perturbações de carga térmica e abertura de porta e velocidade adequada para um rápido resfriamento de produtos frescos. / This work presents an automated system for fresh vegetable food conservation based on electronic instrumentation, a storage chamber, and software for system control, whose procedures were developed in LabView. For conservation the fresh packaged products are stored into a controlled temperature liquid volume (55.3 liters), i.e., an aqueous solution prepared with water and ethylene glycol (2%). This conservation methodology allows to increase shelf time of fresh vegetables by means of reducing the storage temperature range to a safe operating condition without freezing the products. Results have shown the suitability of the developed system, which enables to store fresh products with safety and preserving quality as close as 0.4°C of the freezing point. In a conventional chamber fresh products must be stored considering at least a safety range of 2.0°C, which is much farther from the freezing point. Therefore, these conditions give to the hydro-conservation system large immunity regarding thermal load perturbation as well during door operation and adequate speed for fast cooling processes for fresh products.
7

Uma nova técnica para conservação de alimentos frescos baseada em instrumentação eletroeletrônica automatizada / A new technique for fresh food conservation based on automated electronics instrumentation

Paulo Renato Orlandi Lasso 25 September 2003 (has links)
Neste trabalho é apresentado um sistema automatizado para armazenamento e conservação de alimentos vegetais frescos baseado em instrumentação eletroeletrônica e software de controle desenvolvido em LabView. Para a conservação, os produtos (já embalados) são armazenados imersos em uma solução aquosa preparada com água e um anticongelante como o etileno glicol (2%). Esta metodologia de armazenamento permite aumentar o tempo de prateleira através da redução da temperatura, sem o perigo de congelar os produtos armazenados. Os resultados mostram que a metodologia permite armazenar produtos frescos com segurança a apenas 0,4ºC acima do ponto de congelamento, enquanto que em câmaras convencionais esses devem ser armazenados a, pelo menos, 2,0ºC acima do ponto de congelamento. Essas condições proporcionam ao sistema de hidroconservação maior imunidade a perturbações de carga térmica e abertura de porta e velocidade adequada para um rápido resfriamento de produtos frescos. / This work presents an automated system for fresh vegetable food conservation based on electronic instrumentation, a storage chamber, and software for system control, whose procedures were developed in LabView. For conservation the fresh packaged products are stored into a controlled temperature liquid volume (55.3 liters), i.e., an aqueous solution prepared with water and ethylene glycol (2%). This conservation methodology allows to increase shelf time of fresh vegetables by means of reducing the storage temperature range to a safe operating condition without freezing the products. Results have shown the suitability of the developed system, which enables to store fresh products with safety and preserving quality as close as 0.4°C of the freezing point. In a conventional chamber fresh products must be stored considering at least a safety range of 2.0°C, which is much farther from the freezing point. Therefore, these conditions give to the hydro-conservation system large immunity regarding thermal load perturbation as well during door operation and adequate speed for fast cooling processes for fresh products.
8

Modelling, simulation and control of the filtration process in a submerged anaerobic membrane bioreactor treating urban wastewater

Robles Martínez, Ángel 28 November 2013 (has links)
El reactor anaerobio de membranas sumergidas (SAnMBR) está considerado como tecnología candidata para mejorar la sostenibilidad en el sector de la depuración de aguas residuales, ampliando la aplicabilidad de la biotecnología anaerobia al tratamiento de aguas residuales de baja carga (v.g. agua residual urbana) o a condiciones medioambientales extremas (v.g. bajas temperaturas de operación). Esta tecnología alternativa de tratamiento de aguas residuales es más sostenible que las tecnologías aerobias actuales ya que el agua residual se transforma en una fuente renovable de energía y nutrientes, proporcionando además un recurso de agua reutilizable. SAnMBR no sólo presenta las principales ventajas de los reactores de membranas (i.e. efluente de alta calidad, y pocas necesidades de espacio), sino que también presenta las principales ventajas de los procesos anaerobios. En este sentido, la tecnología SAnMBR presenta una baja producción de fangos debido a la baja tasa de crecimiento de los microorganismos implicados en la degradación de la materia orgánica, presenta una baja demanda energética debido a la ausencia de aireación, y permite la generación de metano, el cual representa una fuente de energía renovable que mejora el balance energético neto del sistema. Cabe destacar el potencial de recuperación de nutrientes del agua residual bien cuando el efluente es destinado a irrigación directamente, o bien cuando debe ser tratado previamente mediante tecnologías de recuperación de nutrientes. El objetivo principal de esta tesis doctoral es evaluar la viabilidad de la tecnología SAnMBR como núcleo en el tratamiento de aguas residuales urbanas a temperatura ambiente. Por lo tanto, esta tesis se centra en las siguientes tareas: (1) implementación, calibración y puesta en marcha del sistema de instrumentación, control y automatización requerido; (2) identificación de los parámetros de operación clave que afectan al proceso de filtración; (3) modelación y simulación del proceso de filtración; y (4) desarrollo de estrategias de control para la optimización del proceso de filtración minimizando los costes de operación. En este trabajo de investigación se propone un sistema de instrumentación, control y automatización para SAnMBR, el cual fue esencial para alcanzar un comportamiento adecuado y estable del sistema frente a posibles perturbaciones. El comportamiento de las membranas fue comparable a sistemas MBR aerobios a escala industrial. Tras más de dos años de operación ininterrumpida, no se detectaron problemas significativos asociados al ensuciamiento irreversible de las membranas, incluso operando a elevadas concentraciones de sólidos en el licor mezcla (valores de hasta 25 g·L-1 ). En este trabajo se presenta un modelo de filtración (basado en el modelo de resistencias en serie) que permitió simular de forma adecuada el proceso de filtración. Por otra parte, se propone un control supervisor basado en un sistema experto que consiguió reducir el consumo energético asociado a la limpieza física de las membranas, un bajo porcentaje de tiempo destinado a la limpieza física respecto al total de operación, y, en general, un menor coste operacional del proceso de filtración. Esta tesis doctoral está integrada en un proyecto nacional de investigación, subvencionado por el Ministerio de Ciencia e Innovación (MICINN), con título ¿Modelación de la aplicación de la tecnología de membranas para la valorización energética de la materia orgánica del agua residual y la minimización de los fangos producidos¿ (MICINN, proyecto CTM2008-06809- C02-01/02). Para obtener resultados representativos que puedan ser extrapolados a plantas reales, esta tesis doctoral se ha llevado a cabo utilizando un sistema SAnMBR que incorpora módulos comerciales de membrana de fibra hueca. Además, esta planta es alimentada con el efluente del pre-tratamiento de la EDAR del Barranco del Carraixet (Valencia, España). / Robles Martínez, Á. (2013). Modelling, simulation and control of the filtration process in a submerged anaerobic membrane bioreactor treating urban wastewater [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34102 / Premios Extraordinarios de tesis doctorales

Page generated in 0.1247 seconds