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  • 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.
11

Diseño e implementacion de control para micro hidraulica Plug & Play

Ramírez del Barrio, Paulina Angélica 07 1900 (has links)
Nuestro pa s posee un gran potencial hidr aulico para la generaci on de energ a el ectrica constituido por gran variedad de ca das de agua y r os de peque~nos caudales (40 a 60 [l/s]). Sin embargo no existe en el mercado una soluci on tecnol ogica que permita su utilizaci on independiente de la caracter sticas del recurso que se tenga; modo de operaci on que se desee, sea conectado a la red el ectrica y/o en forma aislada; que sea de utilizaci on simple y posea una interfaz amigable para el usuario nal. En adici on a lo anterior no se observa en la literatura internacional un esfuerzo por automatizar este tipo de medio de generaci on, lo que constituye un nicho de desarrollo tecnol ogico para el pa s. A modo de mejorar las soluciones existentes de micro-generaci on ( 1 a 100 [kW]) y resolver el problema anterior, se origina en el Centro de Energ a de la Universidad de Chile, la idea de dise~nar una m aquina inteligente que pueda operar en las condiciones antes mencionadas. Surge la Micro Central Hidr aulica (MCH) \Plug & Play". El objetivo de este trabajo de t tulo es dise~nar e implementar un sistema de control electr onico autom atico para esta MCH inteligente de 10 [kW] de potencia, que permita explotar peque~nos recursos hidr aulicos mediante la aplicaci on de electr onica para su automatizaci on. Se toma un modelo gen erico de MCH y se complementa para obtener una simulaci on de la planta y de los controladores de frecuencia y tensi on en operaci on en vac o y con carga aislada. Se aprovechan los actuadores de los que se dispone y modi ca su accionamiento manual a autom atico. Se consigue implementar controladores de tipo PI, con cuidado de la sintonizaci on, que muestran que una estrategia de este tipo es su ciente para controlar un generador sincr onico como el de la MCH. Se implementa el control de tensi on mediante modi caci on de corriente de campo a trav es de un chopper y el control de frecuencia a trav es de resistencias de desahogo, modi cando su potencia consumida. Se obtiene como resultado nal un prototipo de planta MCH, incluyendo la electr onica que necesita para su operaci on y la programaci on del sistema de control. Constituy endose de esta forma la experiencia adquirida en hardware y software la mayor parte del aprendizaje. A futuro se propone modi car el hardware por componentes super ciales a modo de reducir espacio utilizado. Modi car los actuadores por otros m as e cientes. Y como recomendaci on nal se propone reemplazar los actuadores por un equipo de electr onica de potencia que permita que la MCH genere seg un el recurso hidr aulico y el equipo se encargue de adecuar la generaci on a los valores deseados de tensi on y frecuencia.
12

Architecture to Support a Transient America

DePolo, Kelsey 28 June 2021 (has links)
No description available.
13

Molecular and Cytogenetical Dissection of the Rye (Secale cereale L.) Genome Structure / ライムギのゲノム構造の分子及び細胞遺伝学的解析

Li, Jianjian 25 November 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第17963号 / 農博第2031号 / 新制||農||1018(附属図書館) / 学位論文||H25||N4807(農学部図書室) / 30793 / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 遠藤 隆, 准教授 河原 太八, 教授 奥本 裕 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
14

Combined Laparoscopic Incarcerated Herniorrhaphy and Small Bowel Resection

Watson, Scott D., Saye, William, Hollier, Paul A. 01 January 1993 (has links)
Laparoscopic femoral herniorrhaphy using a preperitoneal plug and patch appears to be a feasible laparoscopic approach to femoral hernia. A modified preperitoneal femoral hernia repair with mesh and resection of incarcerated small bowel has been successfully completed under laparoscopic guidance in a 64-year-old patient with incarcerated femoral hernia. To our knowledge, this is the first such case reported in the United States. With further experience, laparoscopic femoral herniorrhaphy could provide a viable alter-native to the standard treatment of femoral hernia.
15

PEV Charging Demand Estimation and Selection of Level 3 Charging Station

Du, Yunke 06 June 2013 (has links)
No description available.
16

Smart DC/DC Wall Plug Design for the DC House Project

Liu, Richard Sinclair 01 December 2017 (has links) (PDF)
The present day duplex wall receptacle in the United States provides 120Vrms AC at 60Hz, which comes from a standard set for AC loads by the National Electrical Manufacturers Association. With a DC system, such as what is used in the DC House project currently being developed at Cal Poly, providing DC power to DC loads presents a technical challenge due to the different required DC operating voltages of the loads. This thesis entails the design and construction of a Smart DC/DC Wall Plug, which can automatically adjust its output voltage to match any required DC load voltages. In the DC House implementation, renewable energy sources generate power to feed a 48V DC Bus. The Smart DC/DC Wall Plug converts power from the 48V bus to the appropriate voltage and power levels needed by the DC loads. The Smart DC/DC Wall Plug relies on load current detection, and uses a 10-bit digital potentiometer and a programmable current DAC to adjust the feedback network, thereby changing the output voltage. A dual channel 100W PCB prototype utilizing a STMF302R8 microcontroller is implemented for this design while confining to the NEMA wall outlet form factor. Results of hardware test verify the functionality of the Smart DC/DC Wall Plug in producing the required DC load voltages. Technical issues during the development of the Smart DC/DC Wall Plug will be described, along with suggestions to further improve from the current design.
17

A multi-agent architecture for plug and produce on an industrial assembly platform

Antzoulatos, N., Castro, E., Scrimieri, Daniele, Ratchev, S. 04 March 2020 (has links)
Yes / Modern manufacturing companies face increased pressures to adapt to shorter product life cycles and the need to reconfigure more frequently their production systems to offer new product variants. This paper proposes a new multi-agent architecture utilising “plug and produce” principles for configuration and reconfiguration of production systems with minimum human intervention. A new decision-making approach for system reconfiguration based on tasks re-allocation is presented using goal driven methods. The application of the proposed architecture is described with a number of architectural views and its deployment is illustrated using a validation scenario implemented on an industrial assembly platform. The proposed methodology provides an innovative application of a multi-agent control environment and architecture with the objective of significantly reducing the time for deployment and ramp-up of small footprint assembly systems. / The reported research has been part of the EU FP7 research project “PRIME”
18

Building a Simulation Model for Evaluating Safety Techniques in Plug-and-Produce Robot Cells

Osman, Hazzaa January 2023 (has links)
This thesis research aims to develop a virtual model utilizing a simulation robot cell comprising one or multiple robots and establishing seamless communication with CMAS (Configurable Multi-Agent System) for control purposes. The successful implementation of this setup yielded significant benefits, particularly in pre-risk assessment for the robot cell in Plug and Produce (P&amp;P) operations. By leveraging the virtual simulation prior to actual deployment, the identification and prevention of collision scenarios within the robot's paths were effectively achieved. The simulation was conducted using ABB Robot Studio software, which was seamlessly connected to CMAS software through the REST API protocol. This integration facilitated efficient data exchange and real-time control, enhancing the overall performance and safety of the robot cell. / <p>21 hp</p>
19

Growth Responses Of Marigold, Zinnia And Vinca Grown In 288 Plug Trays Coated With Zinc Chloride Compounds

Rhoades, Pamela Gail Reid 11 August 2007 (has links)
Greenhouse studies were conducted to determine effects of zinc chloride compounds on foliar and root growth of Marigold (tagetes patula), Zinnia (zinnia elegans) and Vinca (catharanthus roseus). Four different experiments were conducted using zinc chloride compounds applied as a spray on 288 plug trays at rates of 0 (paint only), 3.5, 7, and 14 percent. Experiment I includes examining uptake of zinc into potting media. Experiment II examined plant growth at the various application rates and included a visual survey. Experiment III used microscopic studies to determine effects of zinc compounds on root growth. Experiment IV examined the effect of zinc compound rates on plant survival and if survival was species and treatment rate dependent.
20

Social and Economic Conditions of Temporary Urban Living

Carr, Chance 05 June 2014 (has links)
No description available.

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