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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.
41

Pruning Deciduous Shade Trees

Davison, Elisabeth, DeGomez, Tom 04 1900 (has links)
Revised; Originally published:1999 / 6 pp. / The pruning principles discussed in this publication have proven to provide the best possible out comes including tree longevity and safety. Although trees may live for years following improper pruning their life span and safety may be severely reduced. We encourage proper pruning so that the trees we care for may bring us pleasure for many years.
42

Sistema especialista fuzzy para dimensionamento de bombeio mec?nico

Freitas, Cassio Higino de 22 February 2010 (has links)
Made available in DSpace on 2014-12-17T15:47:52Z (GMT). No. of bitstreams: 1 CassioHF_DISSERT.pdf: 1503543 bytes, checksum: f8c5d434affbf0ef65dde0a97d3eb071 (MD5) Previous issue date: 2010-02-22 / Despite the emergence of other forms of artificial lift, sucker rod pumping systems remains hegemonic because of its flexibility of operation and lower investment cost compared to other lifting techniques developed. A successful rod pumping sizing necessarily passes through the supply of estimated flow and the controlled wear of pumping equipment used in the mounted configuration. However, the mediation of these elements is particularly challenging, especially for most designers dealing with this work, which still lack the experience needed to get good projects pumping in time. Even with the existence of various computer applications on the market in order to facilitate this task, they must face a grueling process of trial and error until you get the most appropriate combination of equipment for installation in the well. This thesis proposes the creation of an expert system in the design of sucker rod pumping systems. Its mission is to guide a petroleum engineer in the task of selecting a range of equipment appropriate to the context provided by the characteristics of the oil that will be raised to the surface. Features such as the level of gas separation, presence of corrosive elements, possibility of production of sand and waxing are taken into account in selecting the pumping unit, sucker-rod strings and subsurface pump and their operation mode. It is able to approximate the inferente process in the way of human reasoning, which leads to results closer to those obtained by a specialist. For this, their production rules were based on the theory of fuzzy sets, able to model vague concepts typically present in human reasoning. The calculations of operating parameters of the pumping system are made by the API RP 11L method. Based on information input, the system is able to return to the user a set of pumping configurations that meet a given design flow, but without subjecting the selected equipment to an effort beyond that which can bear / Apesar do surgimento de outras t?cnicas de eleva??o artificial de petr?leo, sistemas de bombeio mec?nico mant?m-se hegem?nicos devido ? sua flexibilidade de atua??o e custo menor de investimento se comparada com outras t?cnicas de eleva??o desenvolvidas. Um dimensionamento de bombeio mec?nico bem sucedido necessariamente passa pelo atendimento da vaz?o prevista e pelo desgaste controlado dos equipamentos de bombeio utilizados na configura??o montada. Entretanto, a concilia??o destes elementos mostrase particularmente desafiadora, sobretudo para a maioria dos projetistas que lidam com este trabalho, que n?o possuem ainda a experi?ncia necess?ria para chegar a bons projetos de bombeio em tempo h?bil. Mesmo com a exist?ncia de diversos aplicativos computacionais no mercado com o objetivo de facilitar esta tarefa, eles precisam enfrentar um exaustivo processo de tentativa e erro at? chegar a combina??o mais adequada de equipamentos para instala??o no po?o. A proposta do presente trabalho consiste em desenvolver um sistema especialista no dimensionamento de sistemas de bombeio mec?nico. Ele tem a miss?o de guiar um engenheiro de petr?leo na tarefa de selecionar um conjunto de equipamentos apropriados ao contexto provido pelas caracter?sticas do ?leo que ser? produzido. Caracter?sticas como o n?vel de separa??o do g?s, presen?a de elementos corrosivos, possibilidade de produ??o de areia e de parafina??o s?o levados em considera??o na escolha da bomba de fundo, coluna de hastes e unidade de bombeio, bem como as caracter?sticas de opera??o dos mesmos. Ele ? capaz de aproximar seu processo de infer?ncia da forma do racioc?nio humano, o que gera resultados mais pr?ximos daqueles obtidos por um especialista. Para tanto, suas regras de produ??o foram elaboradas com base na teoria dos conjuntos fuzzy, capazes de modelar conceitos imprecisos tipicamente presentes no racioc?nio humano. Os c?lculos dos par?metros operacionais do sistema de bombeio s?o feitos por meio do m?todo API RP 11L. Com base em informa??es de entrada, o sistema ? capaz de retornar ao usu?rio um conjunto de configura??es de bombeio mec?nico que atendam uma determinada vaz?o de projeto, por?m sem submeter os equipamentos selecionados a um esfor?o al?m daquele que possam suportar
43

BMMobile: uma linha de produtos para dimensionamento de bombeio mec?nico em dispositivos m?veis

Sousa, Matheus Alves de 18 November 2010 (has links)
Made available in DSpace on 2014-12-17T15:48:02Z (GMT). No. of bitstreams: 1 MatheusAS_DISSERT.pdf: 2078765 bytes, checksum: 519489af2ea8e5db40a4abaa98e99b28 (MD5) Previous issue date: 2010-11-18 / With the increase of processing ability, storage and several kinds of communication existing such as Bluetooth, infrared, wireless networks, etc.., mobile devices are no longer only devices with specific function and have become tools with various functionalities. In the business field, the benefits that these kinds of devices can offer are considerable, because the portability allows tasks that previously could only be performed within the work environment, can be performed anywhere. In the context of oil exploration companies, mobile applications allow quick actions could be taken by petroleum engineers and technicians, using their mobile devices to avoid potential catastrophes like an unexpected stop or break of important equipment. In general, the configuration of equipment for oil extraction is performed on the work environment using computer systems in desktop platforms. After the obtained configuration, an employee goes to equipment to be configured and perform the modifications obtained on the use desktop system. This management process equipment for oil extraction takes long time and does not guarantee the maintenance in time to avoid problems. With the use of mobile devices, management and maintenance of equipment for oil extraction can be performed in a more agile time once it enables the engineer or technician oil can perform this configuration at the time and place where the request comes for example, near in the oil well where the equipment is located. The wide variety of mobile devices creates a big difficulty in developing mobile applications, since for one application can function in several types of devices, the application must be changed for each specific type of device, which makes the development quite costly. This paper defines and implements a software product line for designing sucker-rod pumping systems on mobile devices. This product line of software, called BMMobile, aims to produce products that are capable of performing calculations to determine the possible configurations for the equipment in the design suckerrod pumping, and managing the variabilities of the various products that can be generated. Besides, this work performs two evaluations. The first evaluation will verify the consistency of the products produced by the software product line. The second evaluation will verify the reuse of some products generated by SPL developed / Com o aumento da capacidade de processamento, armazenamento e a variedade de tipos de comunica??o existentes, como Bluetooth, infravermelho, redes sem fio, etc., os dispositivos m?veis deixaram de ser apenas dispositivos com fun??o especifica e passaram a ser ferramentas com diversos tipos de funcionalidade. No campo empresarial os benef?cios que estes tipos de dispositivos oferecem s?o consider?veis, uma vez que a portabilidade permite que tarefas que antes s? poderiam ser executadas dentro do ambiente de trabalho, possam ser realizadas em qualquer lugar. No contexto de empresas de explora??o de petr?leo, aplica??es m?veis permitem que a??es r?pidas possam ser tomadas por engenheiros e t?cnicos de petr?leo, usando seus dispositivos m?veis, de forma a evitar poss?veis cat?strofes como a parada de um po?o ou quebra de um equipamento importante. Em geral, a configura??o de equipamentos para extra??o de petr?leo ? realizada no ambiente de trabalho usando sistemas computacionais em plataformas desktop. Ap?s a configura??o ser determinada, algum funcion?rio deve ir ao equipamento a ser configurado e executar as modifica??es obtidas na utiliza??o do sistema desktop. Este processo de gerenciamento de equipamentos para a extra??o de petr?leo demanda muito tempo e n?o garante a manuten??o em tempo h?bil de forma a evitar maiores problemas. Com a utiliza??o de dispositivos m?veis, o gerenciamento e manuten??o de equipamentos para extra??o de petr?leo pode ser realizada de forma mais ?gil, uma vez que permite que o engenheiro ou t?cnico de petr?leo possa realizar essa configura??o no momento e local aonde chega a solicita??o, por exemplo, pr?ximo ao po?o onde est? localizado o equipamento. A grande variedade de tipos de dispositivos m?veis gera uma grande dificuldade no desenvolvimento de aplica??es m?veis, uma vez que para que uma aplica??o possa funcionar em diversos tipos de dispositivos, a aplica??o deve sofrer altera??es para cada tipo especifico de aparelho, o que torna o desenvolvimento bastante custoso. Este trabalho define e implementa uma linha de produto de software para dimensionamento de bombeio mec?nico em dispositivos m?veis. Esta linha de produto de software, denominada BMMobile, tem como objetivo gerar produtos que sejam capazes de realizar c?lculos para determinar as configura??es poss?veis para os equipamentos no dimensionamento de bombeio mec?nico, al?m de gerenciar as variabilidades dos diversos produtos que podem ser gerados. Al?m disso, esse trabalho realiza duas avalia??es. A primeira avalia??o permite verificar a consist?ncia dos produtos produzidos pela linha de produto de software. A segunda avalia??o permite avaliar o reuso em alguns produtos gerados pela LPS desenvolvida
44

Detec??o e classifica??o de modos de opera??o do bombeio mec?nico via cartas dinamom?tricas

Lima, Fabio Soares de 30 May 2014 (has links)
Made available in DSpace on 2014-12-17T14:55:21Z (GMT). No. of bitstreams: 1 FabioSL_TESE.pdf: 5888891 bytes, checksum: cd954df5e4af671c3361060293cc5710 (MD5) Previous issue date: 2014-05-30 / Universidade Federal do Rio Grande do Norte / The precision and the fast identification of abnormalities of bottom hole are essential to prevent damage and increase production in the oil industry. This work presents a study about a new automatic approach to the detection and the classification of operation mode in the Sucker-rod Pumping through dynamometric cards of bottom hole. The main idea is the recognition of the well production status through the image processing of the bottom s hole dynamometric card (Boundary Descriptors) and statistics and similarity mathematics tools, like Fourier Descriptor, Principal Components Analysis (PCA) and Euclidean Distance. In order to validate the proposal, the Sucker-Rod Pumping system real data are used / A identifica??o r?pida e precisa de anormalidades de fundo de po?o ? essencial para evitar danos e aumentar a produ??o na ind?stria do petr?leo. Esta tese apresenta um estudo sobre uma nova abordagem autom?tica para a detec??o e classifica??o de modos de opera??o no sistema de Bombeio Mec?nico atrav?s de carta de dinamom?tricas de fundo de po?o. A id?ia principal ? o reconhecimento das condi??es de produ??o do sistema atrav?s do processamento de imagem do carta dinamom?trica de fundo de po?o (Descritores de Fourier) e ferramentas matem?ticas estat?sticas (An?lise de Componentes Principais - PCA) e de similaridade (Dist?ncia Euclidiana). Para validar a proposta, s?o utilizados dados provenientes de sistemas de Bombeio Mec?nico reais
45

Computational modeling of hydraulic transients in the triple function of suction cups and non slam considering the curves admission and expulsion of air / Modelagem computacional de transientes hidrÃulicos em ventosas de trÃplice funÃÃo e non slam considerando as curvas de admissÃo e expulsÃo de ar

JoÃo Marcelo Costa Barbosa 18 December 2015 (has links)
A ventosa de trÃplice funÃÃo atua na admissÃo e/ou expulsÃo de ar contido na tubulaÃÃo, protegendo tubulaÃÃo e equipamentos contra os efeitos decorrentes do acÃmulo de ar e golpe de arÃete. AtravÃs do orifÃcio cinÃtico, ela admite grande quantidade de ar quando a pressÃo no interior da tubulaÃÃo torna-se inferior à atmosfÃrica, e expulsa ar apÃs a separaÃÃo da coluna a uma pressÃo superior à atmosfÃrica. Na regiÃo de admissÃo de ar, a ventosa com orifÃcio âNon Slamâ admite grande volume de ar atravÃs do orifÃcio cinÃtico, e inicia a expulsÃo de ar, atravÃs do mesmo orifÃcio. A partir de um determinado valor de pressÃo positiva, o orifÃcio cinÃtico à fechado e abre-se um orifÃcio de menor diÃmetro, chamado de orifÃcio de "Non Slam", amortecendo, assim, o choque das colunas lÃquidas que estavam separadas. Neste trabalho, propÃe-se uma metodologia para o cÃlculo dos coeficientes de admissÃo e expulsÃo de ar no regime transiente a partir das curvas disponibilizadas pelos fabricantes. O trabalho visa minimizar a falta de informaÃÃes experimentais sobre as ventosas com base nas curvas dos fabricantes para a determinaÃÃo dos coeficientes de admissÃo e expulsÃo de ar. Nesse estudo nÃs comparamos o efeito de se usar um Ãnico coeficiente de descarga de ar para entrada e outro Ãnico para a saÃda de ar versus considerar a variaÃÃo desses coeficientes de descarga à medida que as pressÃes variam. O programa computacional UFC7, escrito em Java, implementa o transiente hidrÃulico com suas condiÃÃes de contorno. / sucker triple function acts on admission and / or expulsion of air in the pipe, protecting piping and equipment against the effects of air and accumulation water hammer. Through kinetic hole, she admits lot of air when the pressure inside the pipe becomes lower than atmospheric, and expels air after separation column at a superatmospheric pressure. The inlet region air, the suction orifice "Non slam" admits large volume of air through the orifice Kinetic and starts expelling air through the same hole. From a certain Positive pressure value, the kinetic orifice is closed and opens a lower orifice diameter hole called "Non slam", cushioning, thus, the shock of columns they were separated liquid. In this paper, we propose a methodology for calculating the admission rates and expulsion of air in transient from the curves provided by the manufacturers. The work aims to minimize the lack of information Experimental suction cups on the basis of the curves for the determination of makers the admission rates and expulsion of air. In this study we compared the effect of using a single air discharge coefficient for input and another for output only Air versus consider the variation of these coefficients discharge pressures as range. The UFC7 computer program written in Java, implements the transient Hydraulic with its boundary conditions
46

The Descriptive Paleontology and Applied Ichthyoarchaeology of the Ponsipa Fauna

Dombrosky, Jonathan 05 1900 (has links)
The archaeology of the Northern Rio Grande region of New Mexico has recently received an increased amount scholarly attention. In particular, understanding past trends in demographics, agricultural productivity, violence, and social networks have been primary goals of archaeological research. Understanding patterns in animal exploitation has, however, received far less attention due to a small yet growing regional zooarchaeological database. Through the identification of animal remains from a site called Ponsipa (occupied ca. A.D. 1300 to 1600), this thesis adds one large dataset to this growing database. In addition, this thesis expands on the pre-impoundment distribution of an endangered native freshwater fish species in the state of New Mexico called the blue sucker (Cycleptus elongatus). The blue sucker is a unique fish that is currently experiencing range reduction across all of its known North American distribution due to anthropogenic habitat fragmentation and degradation. Skeletal remains that were identified from Ponsipa represent the farthest known northern record of its occurrence in the state of New Mexico and highlight the extent of range restriction of the species in the area. The data concerning the historical biogeography of the blue sucker from Ponsipa have implications for the effective conservation and restoration of blue sucker located in the Rio Grande Basin.

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