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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.
61

Desenvolvimento de uma sonda TDR helicoidal para uso em conjunto com o ensaio CPT / Developing a coil TDR probe to use together with the CPT test

Katerin Guerrero Doria 21 August 2015 (has links)
A reflectometria no domínio do tempo permite estimar o teor de umidade de um meio através da sua correlação com a constante dielétrica. Uma sonda helicoidal TDR, que pode ser cravada em conjunto outros ensaios de penetração in situ para a estimativa do teor de umidade em diversas profundidades, tem aplicação interessante para a investigação geotécnica do subsolo. No presente trabalho, uma sonda TDR foi adaptada e utilizada em conjunto ao ensaio CPT para caracterização de um perfil de solo arenoso não saturado que ocorre na região de Bauru (SP). A calibração dessa sonda foi feita em laboratório especificamente para esse solo. As equações de calibração que mostraram os melhores resultados foram definidas correlacionando a constante dielétrica, condutividade elétrica aparente e a massa específica seca com o teor de umidade. Com o intuito de melhorar a acurácia na determinação do teor de umidade em campo e eliminar possíveis interferências no registro da onda eletromagnética, foram efetuadas modificações em algumas características do projeto original dessa sonda. Tais modificações consistiram em separar os eletrodos condutores e as partes metálicas da sonda, e eliminar o cabo coaxial de extensão, conectando a sonda diretamente a um cabo coaxial de 12 m de comprimento. Tais mudanças levaram a uma melhoria significativa na determinação do perfil de teor de umidade do local estudado. Os valores de teor de umidade de campo determinados usando o TDR ao longo de 8 m de profundidade foram comparados com os valores de referência obtidos de amostras deformadas retiradas com trado mecânico. O erro médio na estimativa do perfil de teor de umidade gravimétrico utilizando a sonda TDR helicoidal foi de 1.61%, na última campanha de ensaios realizados. Os resultados dessa pesquisa indicam que esta ferramenta é adequada para estimar do perfil de teor de umidade para uso em conjunto com o ensaio CPT. / The time domain reflectometry allows estimating the moisture content of a medium by means of its correlation with the dielectric constant. A coil TDR probe, which can be driven into the ground together with others in situ penetration tests, can be used to estimate the moisture content at different depths. It is an interesting approach for geotechnical site characterization. In this work, a coil TDR probe was adapted and used in combination with the CPT test for the site characterization of an unsaturated sandy soil profile which occurs in the region of Bauru (SP). The probe calibration was performed in laboratory specifically for that soil. The calibration equation, which presented the best results, were defined correlating the dielectric constant, electrical conductivity and dry density with the moisture content. In order to improve the accuracy for determining the water content in the field and to eliminate possible interference on the electromagnetic wave registration, modifications were made in some characteristics of the original design of this probe. Such modifications consisted in separating the conductive electrodes from the metal parts of the probe, and eliminating the coaxial extension cable, connecting the probe directly to a coaxial cable 12 m long. Such changes have led to a significant improvement in the determination of the moisture content profile of the studied site. The moisture content values determined in situ by using the TDR along 8 m depth were compared with reference values obtained from disturbed soil samples collected using mechanical augers. The root mean square error of the gravimetric water content profile using the TDR coil probe was 1.61% in the last test campaign. The results of this research indicate that this tool is suitable to estimate the gravimetric moisture content together with the CPT test.
62

Financiamento da infraestrutura urbana com base na valorização imobiliária: um estudo comparado de mecanismos de quatro países. / Financing urban infrastructure by means of real estate increase in value: a comparative study os mechanisms of four countries.

Claudio Martins Gaiarsa 31 March 2010 (has links)
O trabalho é uma análise comparada de cinco mecanismos de política urbana praticados em quatro países diferentes: EUA, França, Colômbia e Brasil. Esses mecanismos têm como característica principal o financiamento de melhorias na infraestrutura urbana, com recursos gerados por parte da valorização imobiliária, e apropriados por meio desses mecanismos. São eles: Transfer of Development Rights (TDR) nos EUA, Leyes de la Plusvalia na Colômbia, Zones d´Aménagement Concertée (ZAC) na França, CEPACs e Outorga Onerosa em São Paulo, Brasil. O objetivo do trabalho é identificar princípios e regras comuns entre eles, e analisar suas diferenças mais significativas, e as razões para isso. Os mecanismos são apresentados individualmente e, em seguida, comparados quanto a suas características principais: histórico e objetivos de sua implantação, estrutura legal, método de formação do preço ou valor a ser pago, momento do pagamento e eficácia na geração de benefícios urbanísticos. / This work is a comparative analysis of five different mechanisms or urban policy as they are practiced in four different countries: the USA, France, Colombia and Brazil. The main characteristic these mechanisms have in common is the financing of improvements in the urban infrastructure with resources generated by the increase in value or real estate, and the corresponding capture part of that increase in value. The mechanisms analyzed are: Transfer of Development Rights (TDR) in the USA, Leyes de la Plusvalia, in Colombia, Zones d\'Aménagement Concertée (ZAC) in France, Certificados de Potencial Adicional de Construção (CEPACs) and Outorga Onerosa do Direito de Construir, São Paulo, Brazil. The objective of this work is to identify the principles and rules that they share, analyze the most relevant differences and the reasons for those differences. Each of the mechanisms is presented individually, followed by a comparison of their main characteristics: its objective and history, legal structure, price or value formation, moment of payment, and its effectiveness in generating urban improvement.
63

Validation of hygrothermal material modelling under consideration of the hysteresis of moisture storage

Scheffler, Gregor 12 February 2008 (has links)
The achievable accuracy of hygrothermal building component simulation is significantly dependent on the applied material functions. These functions are determined by the material modelling marking the connection between the basic storage and transport parameters which are obtained from basic measurements, and the storage and transport coefficients which are defined within the balance and flow equations. It is the aim of the present study to develop a flexible and widely applicable material model which is not restricted to the current level of the transport theory. Furthermore, limits and options of this model are to be validated by means of four building materials on the basis of special transient moisture profile measurements. The study’s starting point is a comprehensive investigation of both, the different existing modelling approaches and the available experimental methods to determine basic hygrothermal material parameters. On this basis, the material modelling is set into the context of the heat and moisture transport theory derived from thermodynamics. The involved limits and restrictions are highlighted and options as well as requirements for further developments are pointed out. The developments this study focuses on comprise three fields: experiments for basic property determination, material modelling, and experiments for material model validation. The set of basic material investigation methods has been extended by the drying experiment under defined conditions. The different influences on the drying as well as its application to hygrothermal material model calibration are pointed out and appraised. On this basis, a drying apparatus is designed, built and applied. Ultimately, standardisation criteria and the derivation of a single-value drying coefficient are evaluated. Appropriate extensions are indicated. Based on the bundle of tubes approach, an own material model is developed. It is coupled with a mechanistical approach accounting for serial and parallel structured moisture transport phenomena. The derived liquid water conductivity is adjusted by the help of measured conductivity data close to saturation as well as within the hygroscopic moisture range. Subsequently, two internal modelling parameters are calibrated which is done by numerical simulation of the water uptake and the drying experiment under consideration of the hysteresis of moisture storage. Facilitating its application to the obtained laboratory data, the material model has been implemented into a computer program. It is applied to the four building materials brick, lime-sand brick, aerated concrete and calcium silicate. The adjusted material functions are shown and discussed. In all four cases, the calibration provides an excellent agreement between measured and calculated material behaviour. As experimental basis of the material model validation, the instantaneous profile measurement technique (IPM) has been extended to be applied in Building Physics. Special equipment is developed and measurement procedures are designed. Different models to derive the water content from dielectric data obtained by Time Domain Reflectometry (TDR) measurements are evaluated and implemented. Ultimately, an extensive program of transient moisture profile measurements within the hygroscopic and the overhygroscopic moisture content range is conducted and evaluated. Within the frame of validation, the developments on the experimental as well as on the modelling fields are combined. The IPM experiments are recalculated on the basis of the measured initial and boundary conditions applying the adjusted and calibrated material functions. The comparison of measured and calculated data reveals the power of the developed material modelling just as the consequences of the simplifications made on the transport theory level. The distinct influences of the hysteresis of moisture storage consisting of effects depending on the process history and effects depending on the process dynamics, are proven. By the presented study, the material modelling has been decisively further developed, the set of basic measurement methods has been extended by a substantial experiment and the instantaneous profile measurement technique has been made applicable to Building Physics. Moreover, the influences of the process history and the process dynamics on the moisture transport and the resulting moisture profiles could be shown and proven. By that, not only a material model is now available which perfectly applies to the requirements of flexibility, applicability and extendability. The obtained data provides also a powerful basis for further research and development. / Die Genauigkeit hygrothermischer Bauteilsimulation hängt maßgeblich von den verwendeten Materialfunktionen ab. Sie werden durch die Materialmodellierung bestimmt, welche die Verbindung zwischen den aus Basisexperimenten gewonnenen Speicher- und Transportparametern sowie den innerhalb der Bilanz- und Flussgleichungen definierten Speicher- und Transportkoeffizienten herstellt. Ziel der vorliegenden Arbeit ist zum einen die Entwicklung eines flexiblen, breit anwendbaren und gleichzeitig nicht auf den gegenwärtigen Stand der Transporttheorie beschränkten Materialmodells. Dessen Grenzen und Möglichkeiten sollen zum anderen auf der Grundlage spezieller instationärer Feuchteprofilmessungen anhand von vier Baustoffen untersucht und aufgezeigt werden. Ausgangspunkt der Arbeit ist eine ausführliche Beleuchtung sowohl der vorhandenen Modellansätze als auch der zur Verfügung stehenden experimentellen Methoden zur Bestimmung hygrothermischer Basisparameter. Auf dieser Grundlage wird die Materialmodellierung in den Kontext der aus der Thermodynamik abgeleiteten Wärmeund Feuchtetransporttheorie eingeordnet. Die damit verbundenen Grenzen und Einschränkungen werden hervorgehoben und Entwicklungsmöglichkeiten sowie weiterer Entwicklungsbedarf aufgezeigt. Dieser umfasst drei Bereiche: die Experimente zur Bestimmung von Basisparametern, die Materialmodellierung, sowie Experimente zur Modellvalidierung. Die Reihe der Basisexperimente wird um den Trocknungsversuch unter definierten Bedingungen erweitert. Die verschiedenen Einflüsse auf die Trocknung und deren Anwendung in der Kalibrierung hygrothermischer Materialmodellierung werden herausgestellt und bewertet. Darauf aufbauend wird eine Apparatur entworfen, gebaut und angewendet. Schließlich werden Kriterien zur Standardisierung und Ableitung eines Einzahlenkennwertes evaluiert. Sinnvolle Erweiterungen werden aufgezeigt. Es wird ein eigenes Materialmodell auf der Grundlage eines Porenbündelansatzes hergeleitet, welches mit einem mechanistischen Ansatz gekoppelt wird, der den Feuchtetransport in seriell und parallel strukturierte Bereiche untergliedert. Die abgeleitete Flüssigwasserleitfähigkeit wird anhand von Leitfähigkeitsmessdaten im nahe gesättigten sowie im hygroskopischen Feuchtebereich justiert. Zwei interne Modellparameter werden anschließend unter Berücksichtigung der Hysterese der Feuchtespeicherung anhand des Aufsaug- und des Trocknungsversuches kalibriert. Das Materialmodell ist zur Erleichterung der Anwendung in ein Computerprogramm zur Anpassung an die Labordaten implementiert worden. Das Programm wird auf die vier Baustoffe Ziegel, Kalksandstein, Porenbeton und Calciumsilikat angewendet. Die entsprechend angepassten Materialfunktionen werden gezeigt und diskutiert. Im Rahmen der Kalibrierung wird eine hervorragende Übereinstimmung zwischen gemessenem und berechnetem Materialverhalten erreicht. Zur Modellvalidierung wird die Augenblicksprofilmethode (IPM) für die bauphysikalische Anwendung erweitert. Spezielle Apparaturen werden entwickelt und Versuchsabläufe entworfen. Modelle zur Ableitung des Wassergehaltes aus mit Hilfe der Time Domain Reflectometry (TDR) gewonnenen Dielektrizitätsmessdaten werden evaluiert und implementiert. Schließlich wird ein umfangreiches Programm an Feuchteprofilmessungen im hygroskopischen und überhygroskopischen Feuchtebereich umgesetzt und ausgewertet. Im Rahmen der Validierung werden die Entwicklungen auf experimenteller sowie auf Modellierungsebene zusammengeführt. Die IPM Experimente werden anhand der gemessenen Anfangs- und Randbedingungen und auf der Grundlage der angepassten und kalibrierten Materialfunktionen nachgerechnet. Der Vergleich zwischen Messung und Rechnung offenbart die Stärke der entwickelten Materialmodellierung ebenso, wie den Einfluss der auf Ebene der Transporttheorie getroffenen Vereinfachungen. Ein deutlicher Einfluss der sich aus der Prozessgeschichte sowie der Prozessdynamik zusammensetzenden Hysterese der Feuchtespeicherung kann nachgewiesen werden. Mit der vorliegenden Arbeit ist somit nicht nur die Materialmodellierung entscheidend weiterentwickelt, die Reihe der einfachen Basisexperimente um einen wesentlichen Versuch erweitert und die Augenblicksprofilmethode für bauphysikalische Belange anwendbar gemacht worden, es wurden auch die Einflüsse der Prozessgeschichte, und erstmals auch der Prozessdynamik, auf den Feuchtetransport sowie die sich einstellenden Feuchteprofile deutlich aufgezeigt und nachgewiesen. Es ist demnach nicht nur ein Materialmodell, welches den gestellten Anforderungen an Flexibilität, breite Anwendbarkeit und Erweiterbarkeit genügt, entwickelt worden, es wird mit den gewonnenen Messdaten auch die Grundlage weiterer Forschung zur Verfügung gestellt.
64

Simulation of line fault locator on HVDC Light electrode line

Hermansson, Andreas January 2010 (has links)
In this bachelor thesis, cable fault locators are studied for use on the overhead electrode lines in the HVDC (High Voltage Direct Current) Light project Caprivi Link. The cable fault locators studied operates with the principle of travelling waves, where a pulse is sent in the tested conductor. The time difference is measured from the injection moment to the reflection is received. If the propagation speed of the pulse is known the distance to the fault can be calculated. This type of unit is typically referred to as a TDR (Time Domain Reflectometer). The study is performed as a computer simulation where a simplified model of a TDR unit is created and applied to an electrode line model by using PSCAD/EMTDC. Staged faults of open circuit and ground fault types are placed at three distances on the electrode line model, different parameters of the TDR units such as pulse width and pulse amplitude along with its connection to the electrode line are then studied and evaluated. The results of the simulations show that it is possible to detect faults of both open circuit and ground fault types with a suitable TDR unit. Ground faults with high resistance occurring at long distances can be hard to detect due to low reflection amplitudes from the injections. This problem can somewhat be resolved with a function that lets the user compare an old trace of a “healthy” line with the new trace. The study shows that most of the faults can be detected and a distance to the fault can be calculated within an accuracy of ± 250 m. The pulse width of the TDR needs to be at least 10 μs, preferable 20 μs to deliver high enough energy to the fault to create a detectable reflection. The pulse amplitude seams to be of less significance in this simulation, although higher pulse amplitude is likely to be more suitable in a real measurement due to the higher energy delivered to the fault. The Hipotronics TDR 1150 is a unit that fulfil these requirements and should therefore be able to work as a line fault locator on the electrode line.
65

公共設施保留地容積移轉與競標機制績效之研究 / A study on the performance of the TDR of land reservations for public facilities and bidding mechanism

范振鋒, Fan, Chen Feng Unknown Date (has links)
容積移轉(Transfer of Development Rights, TDR)制度,源自於歐美國家為保護自然環境、生態環境及文化資產所創設之發展權移轉,多應用於歷史古蹟、歷史保存區與環境敏感地區之保護及保存,此外,並利用都市成長管理計畫加以管理。而在台灣地區,因政府長期受限於公共設施保留地取得問題,故而將容積移轉適用範圍擴大應用於公共設施保留地取得,於是各縣市政府陸續依據內政部訂定之「都市計畫容積移轉實施辦法」訂定自治條例。 政府為解決私有既成道路徵收補償問題,於是訂定「中央補助直轄市縣市政府取得私有既成道路試辦計畫」,希望能以競標方式為手段取得私有既成道路,基於私有既成道路因係私有財產權受有財產權制度性保障,以避免民眾權益受到損害,解決社會不公平問題。 本研究採取對容積移轉及競標制度相關理論做文獻回顧,認為藉由實施容積移轉制度確實是一種可保護自然環境、生態環境、文化資產及取得公共設施保留地的一種方法,卻不是唯一可行的方式,在制度面上有許多未盡周延或實際操作上極待克服的課題。 從本研究中發現容積移轉制度的容積價值換算及競標制度的競標價格,並不能真實補償私有公共設施保留地土地所有權長期無法補償的損失,且確實尚未達到各縣市土地徵收補償標準及容積移轉適用性。期望藉由建構競標價格權重分配模型之補償機制,確立合理的競標價格補償比例規範,透過量化標準尋找競標價格補償比例,其目的是作為日後增修法令調整項目核給競標比例之參考。 政府制定及執相關都市計畫政策都應要有宏觀的視野,對於容積移轉及競標政策,我們認為政府的設計與做法應該更謹慎,才是一個政府永續經營的負責態度,才能為人民建立一個安居樂業的生活環境。 / The mechanism of TDR is for the protection of the conservation of natural environment and eco-system and cultural assets in United States and Europe area. Most casts of TDR are used to reserve the historical district and the sensitive areas, in addition to manage the urban development. In Taiwan, the government expands the use of TDR to retain the lands for public-facilities use, in order to resolve the long-tern struggling of the storage of public-facilities lands. Base on the regulation of the 「The Implementation Measures of TDR in Urban Planning」, the local government formulate the measures one after another. The government in order to solve the issue of the compensation for privately owned road expropriation. To formulate the「The central government subsidy municipalities and counties to obtain a privately owned road into a pilot project」, it is hoped that a privately owned road can be obtained by bidding means. Based on the private ownership of the road, because of the system of private property rights protected by property rights. To avoid damage of the public rights and interests. And solve the problem of social unfair. In this thesis, the capacity transfer theory and the bidding mechanism are reviewed. We conclude that the current system of the capacity transfer is one method to conservation of natural environment and eco-system and cultural assets and in the acquisition of the public reserved but not the only best one. There are still some problems in the system, especially in the practical execution aspect. We found that the current formula for the estimation of the capacity value in the capacity transfer system and the bidding price in the bidding mechanism, they do not really compensate the loss of the long-term private ownership of the public reserved. Furthermore, it does not meet the standard of the compensation for expropriating land, neither does the capacity transfer appropriation. Except to build the compensation mechanism of bidding price weighting allocation model. Establish the reasonable compensation proportion specification of bidding price. Find the compensation proportion specification of bidding price through the quantification criteria. The purpose is to adjust the project as a future increase in the proportion of approved bidding reference. The government should have a global consideration in the urban planning and in enhancement of the living quality in the city. For the capacity transfer theory and the bidding mechanism, we suggest that the government should be more prudent designing the system and the execution. For the sustainable management, it is a responsibility for a city government to help citizens lead their happy life.
66

Zoneamento geoambiental com auxílio de lógica fuzzy e proposta de um geoindicador para caracterização do meio físico da Bacia do Rio do Peixe / Geoenvironmental zoning using fuzzy logic and proposal of a geoindicador to characterize Rio do Peixe basin environment

Silva, Sandra Fernandes da 05 July 2005 (has links)
O trabalho apresenta uma proposta metodológica para caracterização de aptidões e restrições do meio físico, considerando a variação contínua dos atributos e também a existência de gradação nos contatos entre as unidades. Os mapas do substrato rochoso e dos materiais inconsolidados foram obtidos utilizando-se de procedimentos da lógica fuzzy para representação da gradação nos contatos. As cartas de declividade, de menor extensão do percurso da água superficial, de potencial de escoamento superficial, de susceptibilidade à erosão e de potencial agrícola foram obtidas utilizando-se mapas numéricos e a variação contínua dos atributos. Para realização das operações de geoprocessamento foram utilizados o sistema de informação geográfica SPRING e a linguagem de programação LEGAL, que permitiram, tanto a representação dos contatos gradacionais (fuzzy) quanto a classificação contínua e o cruzamento das informações. Para avaliação de alterações introduzidas no meio, foi proposta a aplicação do atributo resistência à penetração do solo como geoindicador ambiental. As medidas de resistência à penetração foram feitas utilizando-se um novo equipamento, que consiste de um penetrômetro de solo acoplado a uma sonda TDR. Este procedimento permitiu a caracterização de modificações das condições naturais de compactação dos solos da bacia, frente às atividades de uso do terreno vigentes, bem como forneceu um parâmetro para comparação frente a modificações de uso futuras. O zoneamento da área foi obtido a partir da adoção das unidades de lanforms como unidades de compartimentação, o que possibilitou a caracterização das aptidões, restrições e conflitos de uso / This study presents a methodological technique to characterize environmental restrictions and aptitudes considering continuous variation in the attributes and gradation in contato between units. Fuzzy logic procedures were used to generate representation of contact gradation for rocky substratum and unconsolidated materials maps. Continuous attribute variation and numerical maps were used to produce slope least water runoff distance, runoff potential, erosion susceptibility and agricultural potential charts. Geoprocessing operations using the SPRING geographical information system and its LEGAL programming language permitted the representation of gradation in contac (fuzzy), continuous classification nad information crossing. Soil penetration resistance was proposed as the environmental geondicator to evaluate environmental changes. Measurement of soil penetration resistance by a soil penetrometer connected to a TDR proble permitted the characterization and specification of natural basin soil compaction conditions and the comparison of different occupation activities on the soil. A parameter for future changes due to soil occupation was therefore identified by this procedure. Area zoning was attained by the adoption of landform units as segmentation units. The characterization of aptitudes, restrictions and conflicts in occupation were achived by this procedure
67

TDRs與原上市地股票價格關係之探討 / Price transmission dynamics between TDRs and the underlying foreign securities

張韡華 Unknown Date (has links)
台灣存託憑證(TDRs)從2009年起在台盛行,至今有三十五檔TDRs在台灣證劵交易所掛牌,各檔TDRs交易期間至今約半年至三年不等,目前TDRs檔數和交易時間已足以做比較和計量檢定,因此本文以在台灣證劵交易所掛牌之TDRs為對象,選取13檔TDRs做實證研究,資料期間為各檔TDRs上市日至2012年2月17日的日資料。研究內容包含兩部分:1.透過單根檢定、共整合檢定、VAR模型、Granger關係檢定和誤差修正模型等實證分析,觀察兩地股價是否具有長期的穩定關係和價格發現功能,以及股價波動是否具有因果關係;2.近年來台灣的相關法規是否對TDRs交易機制有正向幫助。實證結果主要如下:1.大部分TDRs結果顯示股價、匯率和大盤指數間具有長期的穩定關係,即是有共整合現象;誤差修正模型(VECM)中各變數的係數大多不顯著,也就是說各變數在短期並無法透過此模型來預測股價;2.在因果檢定方面,樣本中有5檔TDRs的原股股價對TDRs股價有領先效果,另外8檔TDRs的原股股價和TDRs股價間並沒有顯著的領先或落後效果;3.台灣近年陸續發布的相關法規確實改善市場的供需問題 和價格偏離現象,對投資人有正面幫助。
68

Zoneamento geoambiental com auxílio de lógica fuzzy e proposta de um geoindicador para caracterização do meio físico da Bacia do Rio do Peixe / Geoenvironmental zoning using fuzzy logic and proposal of a geoindicador to characterize Rio do Peixe basin environment

Sandra Fernandes da Silva 05 July 2005 (has links)
O trabalho apresenta uma proposta metodológica para caracterização de aptidões e restrições do meio físico, considerando a variação contínua dos atributos e também a existência de gradação nos contatos entre as unidades. Os mapas do substrato rochoso e dos materiais inconsolidados foram obtidos utilizando-se de procedimentos da lógica fuzzy para representação da gradação nos contatos. As cartas de declividade, de menor extensão do percurso da água superficial, de potencial de escoamento superficial, de susceptibilidade à erosão e de potencial agrícola foram obtidas utilizando-se mapas numéricos e a variação contínua dos atributos. Para realização das operações de geoprocessamento foram utilizados o sistema de informação geográfica SPRING e a linguagem de programação LEGAL, que permitiram, tanto a representação dos contatos gradacionais (fuzzy) quanto a classificação contínua e o cruzamento das informações. Para avaliação de alterações introduzidas no meio, foi proposta a aplicação do atributo resistência à penetração do solo como geoindicador ambiental. As medidas de resistência à penetração foram feitas utilizando-se um novo equipamento, que consiste de um penetrômetro de solo acoplado a uma sonda TDR. Este procedimento permitiu a caracterização de modificações das condições naturais de compactação dos solos da bacia, frente às atividades de uso do terreno vigentes, bem como forneceu um parâmetro para comparação frente a modificações de uso futuras. O zoneamento da área foi obtido a partir da adoção das unidades de lanforms como unidades de compartimentação, o que possibilitou a caracterização das aptidões, restrições e conflitos de uso / This study presents a methodological technique to characterize environmental restrictions and aptitudes considering continuous variation in the attributes and gradation in contato between units. Fuzzy logic procedures were used to generate representation of contact gradation for rocky substratum and unconsolidated materials maps. Continuous attribute variation and numerical maps were used to produce slope least water runoff distance, runoff potential, erosion susceptibility and agricultural potential charts. Geoprocessing operations using the SPRING geographical information system and its LEGAL programming language permitted the representation of gradation in contac (fuzzy), continuous classification nad information crossing. Soil penetration resistance was proposed as the environmental geondicator to evaluate environmental changes. Measurement of soil penetration resistance by a soil penetrometer connected to a TDR proble permitted the characterization and specification of natural basin soil compaction conditions and the comparison of different occupation activities on the soil. A parameter for future changes due to soil occupation was therefore identified by this procedure. Area zoning was attained by the adoption of landform units as segmentation units. The characterization of aptitudes, restrictions and conflicts in occupation were achived by this procedure
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Monitoramento de uma solução de nitrato de potássio em um latossolo vermelho-amarelo com uso da técnica de TDR / Monitoring of a nitrate and potassium solution in a red yellow latossolo with use of the techinician TDR

Leonardo do Nascimento Lopes 02 February 2009 (has links)
O conhecimento da movimentação da água no solo é de grande importância para a agricultura, pois a água é um dos fatores que mais influenciam no rendimento das culturas. Das várias técnicas utilizadas para o monitoramento do conteúdo de água no solo, a reflectometria no domínio do tempo (TDR) vem sendo bastante difundida entre os pesquisadores por apresentar inúmeras vantagens, dentre as quais a mensuração em tempo real e a possibilidade de leituras automatizadas. Com o objetivo de avaliar a movimentação da água num perfil de um Latossolo vermelho-amarelo, conduziu-se um experimento obtendo-se os valores de umidade do solo e condutividade elétrica através das leituras de um equipamento de TDR com sondas instaladas em uma trincheira em diversas profundidades (0,10 m a 0,60 m) e com diferentes taxas de aplicação (2, 4 e 8 L.h-1) de solução em intervalos de 1 hora, via irrigação por gotejamento. A partir dos resultados obtidos, pôde concluir-se que diferentes vazões de aplicação determinam características particulares de formação do bulbo molhado e da movimentação da solução no solo. Para as condições de solo e de acordo com o volume e a frequência utilizada durante este experimento, recomenda-se a aplicação de pequenas quantidades de solução em intervalos mais frequentes para reduzir a perda por percolação de água e solutos. / The knowledge of the water distribution in soil has great importance to the agriculture because of the crop yield the cultures income has a direct influence by the water. There are many techniques used to monity soil moisture, and the time domain reflectometry (TDR), has a satisfactory application among the researches because the advantages, allow the real time measurements can be automatized and the automatized. With the objective to appraise the water distribution and electrical conductivity in a Red-yellow Latosol profile, the experiment was conducted measuring soil moisture through the TDR equipment reading with probes fixed in a trench in various depths (0,10 m to 0,60 m) and with different applications rates of solution (2,4 and 8 L.h-1) , with one hour interval by dripping irrigation. The results allowed us to that the different sewages applications determinate the particular characteristics of the wet bulb arrangement and the water soil distribution. For the soil conditions and according to the volume and frequency used during this experiment, it is recommended to apply of small quantities of a solution at more frequent intervals to reduce the loss by percolation of water and solute.
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Multiphysics Simulation and Innovative Characterization of Freezing Soils

Liu, Zhen 08 March 2013 (has links)
No description available.

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