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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

Recherche de la Vibration Géante de Paires & Mesure du temps de vie du premier état excité 2+ du 74Zn par méthode plunger.

Mouginot, B. 17 December 2010 (has links) (PDF)
Ma thèse se compose de deux parties indépendantes. Dans un premier temps, j'ai participé à la réalisation et à l'analyse d'une expérience réalisée au GANIL ayant pour but d'étudier l'évolution de la structure des isotopes du zinc riches en neutrons. Lors de cette expérience nous avons mesuré le temps de vie du premier état excité du 74Zn par méthode plunger. Le faisceau radioactif de 74Zn utilisé (34 MeV/u) a été produit par fragmentation en vol et purifié avec la première moitié du spectromètre LISE. La seconde moitié du spectromètre a été utilisée pour l'identification du produit final de la réaction. Le multidétecteur EXOGAM couplé avec le dispositif plunger a permis la détection des photons g émis en vol et la mesure de temps de vie de l'ordre de quelques dizaines de picosecondes. Nous avons, après l'analyse des données, établi le temps de vie du premier état excité 2+ du 74Zn à t = 29(3) ps. En comparant cette mesure directe du temps de vie avec les résultats d'excitation coulombienne réalisée à ISOLDE [Wall 09], nous avons déterminé le moment quadripolaire du 74Zn. Cette mesure constitue la première contrainte sur la déformation des isotopes de zinc ayant plus de 40 neutrons (remplissant l'orbitale neutron g9=2). Durant la seconde partie de ma thèse, je me suis concentré à la réalisation et à l'analyse de deux expériences de transfert (120Sn(p; t)118Sn et 208Pb(p; t)206Pb) réalisées à iThemba LABs (Afrique du Sud). Ces deux expériences, utilisant la méthode de la masse manquante, avaient pour but d'identifier la Vibration Géante de Paires ou Giant Pairing Vibration (GPV). Ce mode collectif analogue à une résonance géante correspond à une excitation cohérente de paires au sein de la couche majeure suivant le niveau de Fermi. Cette résonance géante suggérée par de nombreux calculs théoriques (QRPA [Khan 09] et TDHFB [Avez 08]) reste, malgré les différents efforts visant à l'identifier [Craw 77], toujours sans preuve expérimentale. Ces deux expériences ont été réalisées dans les conditions idéales, quant à l'observation de la GPV : - un faisceau de protons à relativement faibles énergies (50 et 60 MeV), favorisant les états de faible spin, - un spectromètre (K600) utilisé à des angles faibles (7 et 0°), le transfert L=0 (vibration de paires) ayant un section efficace très piquée à 0°. Bien qu'ayant une nouvelle fois aucun indice clair de présence de GPV, nous avons pu établir une valeur maximale sur la section efficace de population dans le canal de transfert de deux neutrons de la GPV dans ces noyaux.
12

Mathematical modelling of the plunger pump operation with numerical methods for simulating the flow across the valve

Chen, Tian 01 December 2011 (has links)
Plunger pumps are needed for heavy duty sludge pumping at wastewater treatment facilities. America's leading pump manufacturer Wastecorp Inc. brought their plunger pump problem to us in late 2009. It was found that when the ow rate reaches a critical value, the plunger pump starts to generate a clicking noise. A one-dimensional model was built for studying the ow of a typical plunger pump operation. The velocities and pressures are calculated at certain interesting locations. Pressure jumps have been found while opening or closing the valves. The valve motion is then modeled with considerations to its geometry. The results show that as the plunger speed reaches a critical value, the valve moves more rapidly and more likely to hit the wall and generates a noise. We also provide a methodology to study the ow across the valve in higher resolution. A nite-di erence approach to the Navier-Stokes equations are presented with the immersed boundary method. / UOIT
13

Transcribing Al Grey: A Legacy Defined by Thirteen Improvisations

January 2011 (has links)
abstract: The study of artist transcriptions is an effective vehicle for assimilating the language and style of jazz. Pairing transcriptions with historical context provides further insight into the back story of the artists' life and method. Innovators are often the subject of published studies of this kind, but transcriptions of plunger-mute master Al Grey have been overlooked. This document fills that void, combining historical context with thirteen transcriptions of Grey's trombone features and improvisations. Selection of transcribed materials was based on an examination of historically significant solos in Al Grey's fifty-five-year career. The results are a series of open-horn and plunger solos that showcase Grey's sound, technical brilliance, and wide range of dynamics and articulation. This collection includes performances from a mix of widely available and obscure recordings, the majority coming from engagements with the Count Basie Orchestra. Methods learned from the study of Al Grey's book Plunger Techniques were vital in the realization of his work. The digital transcription software Amazing Slow Downer by Roni Music aided in deciphering some of Grey's more complicated passages and, with octave displacement, helped bring previously inaudible moments to the foreground. / Dissertation/Thesis / Video File of Al Grey's Accompaniment to Joe Williams on "It's a Low Down Dirty Shame" from Astaire Time (1960) / Video File of Al Grey's Solo on Okay with Jay from Sitting In with Buddy Rich (1986) / D.M.A. Music 2011
14

Výroba tvárníku formy / Production of the mold plunger

Rosa, Jakub January 2017 (has links)
The meaning of the diploma thesis is to create a new mold plunger for injection mold using a suitable method according to the original mold plunger. The final mold part should meet the required surface parameters. The work is focused on the analysis of the original mold plunger and the experimental verification of suitable methods of production of the equivalent mold plunger.
15

Racionalizace výroby dílů vstřikovacích čerpadel / The Rationalization of Production Part of Injection Pump

Havel, Marian January 2011 (has links)
This thesis focuses on the rationalization of the production process of plungers and elements of injection pumps in relation to improving the quality of the final products. Today’s technology, which mainly uses single-purpose machines where the production quality markedly depends on the abilities and activities of the operator, will replaced by modern machining centres and CNC machines for grinding all functional parts of the plungers, coupled with modern measuring devices. These production machines with the support of measuring devices will improve the productivity of production and the general quality of the produced components.
16

Desenvolvimento de um software de comunica??o sem fio aplicado ? instrumenta??o de unidade de eleva??o de petr?leo tipo Plunger Lift

Oliveira, Felipe Denis Mendon?a de 13 February 2009 (has links)
Made available in DSpace on 2014-12-17T14:55:35Z (GMT). No. of bitstreams: 1 FelipeDMO.pdf: 2614728 bytes, checksum: fd69e303891800912ab5260562a5545d (MD5) Previous issue date: 2009-02-13 / This dissertation aims to develop a software applied to a communication system for a wireless sensor network (WSN) for tracking analog and digital variables and control valve of the gas flow in artificial oil s elevation units, Plunger Lift type. The reason for this implementation is due to the fact that, in the studied plant configuration, the sensors communicate with the PLC (Programmable and Logic Controller) by the cables and pipelines, making any changes in that system, such as changing the layout of it, as well as inconveniences that arise from the nature of the site, such as the vicinity s animals presence that tend to destroy the cables for interconnection of sensors to the PLC. For software development, was used communication polling method via SMAC protocol (Simple Medium Access ControlIEEE 802.15.4 standard) in the CodeWarrior environment to which generated a firmware, loaded into the WSN s transceivers, present in the kit MC13193-EVK, (all items described above are owners of Freescale Semiconductors Inc.). The network monitoring and parameterization used in its application, was developed in LabVIEW software from National Instruments. The results were obtained through the observation of the network s behavior of sensors proposal, focusing on aspects such as: indoor and outdoor quantity of packages received and lost, general aspects of reliability in data transmission, coexistence with other types of wireless networks and power consumption under different operating conditions. The results were considered satisfactory, which showed the software efficiency in this communication system / Este trabalho tem por finalidade desenvolver um software aplicado a um sistema de comunica??o de uma rede de sensores sem fio (RSSF), para monitoramento de vari?veis anal?gicas, digitais e comando de v?lvulas de passagem do fluxo de g?s em unidades de eleva??o artificial de petr?leo e g?s natural do tipo Plunger Lift. A raz?o desta implementa??o deve-se ao fato que, na configura??o da planta estudada, os sensores comunicam-se com o CLP (Controlador L?gico Program?vel) atrav?s de cabos e dutos, dificultando eventuais modifica??es nesse sistema, tais como mudan?a de layout do mesmo, al?m de inconveni?ncias que venham a surgir da pr?pria natureza do local, como a presen?a de animais nas redondezas que tendem a destruir os cabos de interconex?o dos sensores ao CLP. Para o desenvolvimento do software, foi utilizado o m?todo de comunica??o polling, atrav?s do protocolo SMAC (Simple Medium Access Control - padr?o IEEE 802.15.4), no ambiente CodeWarrior, ao qual gerou um firmware, carregado nas placas de monitoramento da RSSF, presentes no kit MC13193-EVK, (todos os itens descritos acima s?o propriet?rios da Freescale Semiconductors Inc.). O monitoramento e parametriza??o da rede utilizou uma aplica??o, desenvolvida no software LabVIEW, da National Instruments. Os resultados foram obtidos atrav?s da observa??o do comportamento da rede de sensores proposta, focando aspectos, tais como: quantidade de pacotes recebidos e perdidos em ambientes externos (Outdoor) e internos (Indoor), aspectos gerais de confiabilidade na transmiss?o dos dados, coexist?ncia entre outros tipos de redes sem fio e consumo de energia sob diferentes condi??es de opera??o. Os resultados obtidos foram considerados satisfat?rios, o que comprovou a efici?ncia do software neste sistema de comunica??o
17

Development Of Expert System For Artificial Lift Selection

Aliyev, Elshan 01 February 2013 (has links) (PDF)
During the reservoir production life reservoir pressure will decline. Also after water breakthrough the fluid column weight will increase as hydrostatic pressure will increase because of increased water and oil mixture density. In this case, reservoir pressure may not be enough to lift up the fluid from bottom to the surface. These reasons decrease or even may cause to stop flowing of fluids from the well. Some techniques must be applied to prevent the production decline. Artificial lift techniques are applied to add energy to the produced fluids. It increases production rate by reducing down-hole pressure and so that by increasing the drawdown. Artificial lift techniques increase production either by pumping the produced fluid from the bottom to the surface or reduce bottom-hole pressure by reducing the fluid column weight as a result of decreased fluid mixture density. Artificial lift is used worldwide in approximately 85% of the wells, thus its impact in overall efficiency and profitability of production operations cannot be overemphasized. The most important problem is how to select optimum artificial lift techniques by taking into consideration the reservoir, well, environmental conditions. Selection of poor technique could cause decrease in efficiency and low profitability. As a result, it will lead to high operating expenses. Several techniques have been developed for selection of optimum artificial lift techniques. Expert Systems (ES) is the most suitable technique used in these selection techniques. Because the use and availability of required parameters is easy. Also in this selection method most of the artificial lift techniques are analyzed rather than other selection techniques. Expert Systems program mainly consist of three modules: (1) Expert Module, (2) Design Module, and (3) Economic Module. By entering required data to the system, program automatically suggests the feasible artificial lift techniques those might be used referring to given data. In this thesis work the artificial lift selection criteria and Expert Systems available in the literature have been studied. A Microsoft Windows based program has been developed to predict suitability of artificial lift methods for a given set of wells and produced fluid parameters. For the selected artificial lift method (i.e. sucker rod pump, ESP, gas lift, hydraulic pump, PCP) the program is able to perform basic calculations for the given data. Different case studies have been performed by running the program with actual data from fields. Well data of Venezuela, Azerbaijan and Iranian oil fields has been used in case studies. The results have been compared with previous studies those have been done on these fields with other selection techniques and current artificial lift techniques are being applied in selected wells. The obtained program results have been overlap with current real field application and previous studies.
18

Simulador computacional do m?todo de eleva??o artificial Plunger Lift e implementa??o de controladores para estudo comparativo

Silva, Danielson Fl?vio Xavier da 10 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-02T23:37:04Z No. of bitstreams: 1 DanielsonFlavioXavierDaSilva_DISSERT.pdf: 3822953 bytes, checksum: 058ad7d6c4479d187704c913aa3a0361 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-07T00:15:00Z (GMT) No. of bitstreams: 1 DanielsonFlavioXavierDaSilva_DISSERT.pdf: 3822953 bytes, checksum: 058ad7d6c4479d187704c913aa3a0361 (MD5) / Made available in DSpace on 2017-10-07T00:15:00Z (GMT). No. of bitstreams: 1 DanielsonFlavioXavierDaSilva_DISSERT.pdf: 3822953 bytes, checksum: 058ad7d6c4479d187704c913aa3a0361 (MD5) Previous issue date: 2017-07-10 / Este trabalho aborda o m?todo de eleva??o artificial chamado plunger lift, que ? utilizado em po?os com baixa press?o de reservat?rio. Este m?todo utiliza um ?mbolo mec?nico para auxiliar a subida do ?leo do fundo do po?o at? a superf?cie, atrav?s do fechamento e abertura do po?o com intervalo de tempo distintos. O plunger lift possui algumas etapas que, quando conclu?das, completam um ciclo. Foi desenvolvido um simulador em Java R com o modelo matem?tico implementado no projeto AUTOPOC, desenvolvido no Laborat?rio de Automa??o em Petr?leo, na linguagem C++. Foram implementados dois tipos de controle liga-desliga para este m?todo: controle por temporiza??o e controle por press?o de revestimento. Por fim, resultados s?o obtidos com o simulador, os quais s?o comparados para uma an?lise detalhada e conclus?es acerca do desempenho dos controladores implementados. / This work aboard the artificial lift method named plunger lift, that is used in wells with low reservoir pressure. This method uses a mechanical plunger to help the oil lift from the bottom of the well to the surface through the well, closing and opening with different time interval. The plunger lift has some stages that, when concluded, complete a cycle. It was developed a simulator in Java R with mathematical model implemented in the AUTOPOC, project developed at Laborat?rio de Automa??o em Petr?leo, in C++ language. It were implemented two types of on-off controls for this method: time control and control by casing pressure. Finally, results are obtained with the simulator, what are compared for detailed analysis and take conclusions about the performance of the implemented controllers.
19

Úprava hydraulické části plunžrového čerpadla na vyšší tlaky / Hydraulic part of plunger pump adjustment for higher pressures

Dvořák, Petr January 2018 (has links)
First part of the master thesis is about displacement pump. Second part is about power plunger pumps. In the third part are equations for power plunger pumps. In the last part the strength calculation of the proposed hydraulic part of the plunger pump was performed using the finite element method in ANSYS. The screw fatigue life is also calculated here. At the end of this section, ANSYS Fluent flow calculation is performed in the suction valve area.
20

Estimador de estados para Plunger Lift

Dourado J?nior, Osmar de Ara?jo 19 June 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-01-24T12:15:33Z No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-01-26T14:00:19Z (GMT) No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) / Made available in DSpace on 2018-01-26T14:00:19Z (GMT). No. of bitstreams: 1 OsmarDeAraujoDouradoJunior_TESE.pdf: 3621125 bytes, checksum: ac4c7dbcd5830c2fa16d1e8be1ae3ee1 (MD5) Previous issue date: 2017-06-19 / O objetivo desta Tese ? apresentar um Estimador de Estado para po?os de Plunger Lift com base no algoritmo Extended Kalman Filter (EKF). O estimador de estado ? uma opera??o conjunta da aplica??o para o modelo din?mico de Plunger Lift (PL) na abordagem de Espa?o de Estados e algoritmo EKF. O modelo ? constitu?do por um conjunto de equa??es diferenciais e alg?bricas (DAEs) discretas e modeladas na forma de equa??es no espa?o de estados, levando em conta os sinais de medi??o na presen?a de ru?do. O algoritmo EKF ? aplicado ao modelo de espa?o de estado, resultando num estimador de estado capaz de processar o sinal de medi??o, proporcionando assim estimativas das vari?veis de estado, que neste problema s?o a velocidade da golfada e a press?o no topo do revestimento. A simula??o computacional realizada com dados de um po?o real ? apresentada e os resultados mostraram que o estimador de estados proposto ? capaz de fornecer predi??es para po?os de petr?leo operados por PL. / The aim of this Thesis is to present a State Estimator for Plunger Lift wells based on the Extended Kalman Filter (EKF) algorithm. The state estimator is a joint operation of the application for the Plunger Lift (PL) dynamic model in State Space approach and EKF algorithm. The model is constituted by a set of discrete differential algebraic equations (DAEs) discretized and modeled in the form of equations in state space taking into account the measurement signals in the presence of noise. EKF algorithm is applied to the state space model, resulting in a state estimator able to process the measurement signal thus providing estimates of the state variables, that in this problem are slug velocity and casinghead pressure. The computational simulation performed with data from a real well is presented and the results showed that the state estimator proposed is able to provide predictions for oil wells operated by PL.

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