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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.
31

Medidas das concentrações de rádio em águas minerais disponíveis à venda no Brasil

Kappke, Jaqueline 13 March 2013 (has links)
CAPES / Este trabalho apresenta os resultados da pesquisa sobre medidas da atividade de 226Ra em águas minerais engarrafadas compradas em estabelecimentos comerciais do Brasil. As medidas foram realizadas no Laboratório de Física Nuclear Aplicada da Universidade Tecnológica Federal do Paraná em cooperação com o Centro de Desenvolvimento e Tecnologia Nuclear (CDTN) da Comissão Nacional de Energia Nuclear (CNEN). O trabalho avalia a possibilidade do uso do equipamento RAD7 (Durridge Company) para medir a atividade de 226Ra em equilíbrio com 222Rn presente nas amostras de águas em nível compatível com 0,1Bq/L, o que significa uma precisão superior à prática usual do equipamento. Além disso, a pesquisa fornece o erro mínimo de medida da concentração de atividade do rádio possível de ser atingida com o uso do equipamento RAD7. A principal dificuldade encontrada na técnica desenvolvida foi diminuir os erros associados às medidas. Para desenvolver a metodologia otimizada foram realizados diversos testes que propiciaram a diminuição dos erros e asseguraram uma técnica inovadora para medidas de baixas concentrações de 226Ra em água, com o uso do detector eletrônico de radônio RAD7. O arranjo experimental foi baseado no detector eletrônico de radônio RAD7 e as medidas foram realizadas utilizando o kit RAD H2O que permite identificar a atividade de concentração do 222Rn em pequenas amostras de 40mL e 250mL. Os resultados mostraram que o erro mínimo ficou entre 0,02 a 0,07 Bq/L o que configura uma diminuição considerável e importante nos erros associados às amostras de baixas concentrações. Quando aplicada a metodologia otimizada e proposta, foi possível concluir que todas as amostras analisadas apresentaram valores abaixo que os estabelecidos pelas normas e recomendações e que os valores encontrados para as amostras possuem ordem de grandeza semelhante às encontradas na literatura. Desta forma, foi possível concluir que o detector eletrônico de radônio RAD7 pode ser utilizado nas medidas de 226Ra em águas para concentrações menores que 0,1 Bq/L, mas que para isto deve ser utilizada uma técnica como esta desenvolvida para otimizar o procedimento. / This thesis presents the survey results of measuring the activity of 226Ra in bottled mineral waters purchased in Brazilian market. The measurements were performed at the Laboratory of Applied Nuclear Physics at Federal Technological University of Paraná in cooperation with the Centre for Development and Nuclear Technology (CDTN) of the National Nuclear Energy Commission (CNEN). The study evaluates the possibility of using RAD7 equipament (Durridge Company) in order to measure 226Ra activity in equilibrium with 222Rn present in water samples at a level compatible with 0.1 Bq/L, which means greater accuracy than the usual practice of the equipment. Furthermore, the search provides the minimum error of radio activity concentration that can be achieved using the RAD7 equipament. The main difficulty of this work was to reduce the associated errors to the measure. To develop the optimized methodology were performed several tests that enabled the reduction of errors and ensure an innovative technique for measuring low concentrations of 226Ra in water, using the RAD7 radon electronic¬ detector. The experimental setup was based on the RAD7 and measurements were performed using the RAD H2O kit that identifies the activity concentration of 222Rn in small samples of 250mL. The results showed that the minimum error ranged from 0.02 to 0.07 Bq/L which constitutes a considerable and significant reduction in errors associated with low concentrations samples. When applied the optimized methodology proposed, it was concluded that all the samples had values below the established standards and recommendations and that the values found for the samples have similar order of magnitude to those found in the literature. Thus, the RAD7 radon detector electronics can be used in measurements of 226Ra in water at concentrations below 0,1 Bq/L, but for that, the technique developed in order optimize the procedure should be used.
32

Emprego de redes neurais artificiais com skip-layer connections na mensura??o florestal / Artificial neural networks with skip-layer connections in forest measurement

Silva, Paula Ventura da 11 December 2015 (has links)
Submitted by M?rden L?les (marden.inacio@ufvjm.edu.br) on 2016-07-12T23:59:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-07-18T14:50:22Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) / Made available in DSpace on 2016-07-18T14:50:22Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) paula_ventura_silva.pdf: 2872431 bytes, checksum: 13667045a80e3b80429055fd7e4a5e15 (MD5) Previous issue date: 2015 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / RESUMO SILVA, Paula Ventura da, M.Sc., Emprego de redes neurais artificiais com Skip-Layer Connections na mensura??o florestal. 2015. 46 f. Disserta??o (Mestrado em Ci?ncia Florestal) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. O objetivo principal deste estudo foi avaliar a aplica??o de Redes Neurais Artificiais (RNA) utilizando a t?cnica Skip-layer connections, com e sem recorr?ncia, para estima??o do volume individual e da altura total de ?rvores de eucalipto. Os objetivos espec?ficos foram testar e avaliar as redu??es no tamanho da base de dados do conjunto de ajuste (treinamento) para estima??o dessas vari?veis. Os dados utilizados foram provenientes de ?rvores abatidas para cubagem (estima??o do volume individual) e de medi??es de parcelas permanentes de invent?rios florestais cont?nuos (estima??o da altura total), em ?rea de povoamentos de eucalipto localizados no sul da Bahia, Brasil. Foram treinadas redes do tipo Multilayer Perceptron (MLP), utilizando a fun??o de ativa??o log?stica nas camadas intermedi?ria e de sa?da e oito neur?nios na camada oculta. O n?mero de neur?nios na camada de entrada variou conforme o n?mero e o tipo de vari?vel (qualitativa ou quantitativa) em cada estudo. Os crit?rios de parada foram o erro m?dio quadr?tico de 0,0001 ou 3.000 ciclos (?pocas). Em seguida, as RNA selecionadas foram aplicadas em parte dos dados separados, para generaliza??o (valida??o). O software utilizado para o treinamento e a generaliza??o das RNA foi o NeuroForest 3.3. Para compara??o dos resultados obtidos pelas RNA, foram ajustados os modelos tradicionais de regress?o tanto para volume, quanto para altura, e tamb?m foram treinadas e aplicadas RNA usando o algoritmo Resilient Propagation, comumente utilizado em aplica??es da mensura??o florestal. A avalia??o dos resultados gerados pelas RNA e pelos modelos de regress?o foi feita por meio do coeficiente de correla??o entre os valores observados e estimados, de gr?ficos de dispers?o e de histogramas de frequ?ncia percentual dos erros percentuais. As Redes Neurais Artificiais utilizando Skip-layer connections apresentaram resultados satisfat?rios para estima??o de volume e de altura de ?rvores de eucalipto, o que evidencia a possibilidade de aplicar a t?cnica em mensura??o e manejo florestal e uma expressiva redu??o das bases de dados para treinamento das RNA. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT SILVA, Paula Ventura da, M.Sc. Artificial neural networks with skip-layer connections in forest measurement. 2015. 46 f. Dissertation (Master in Forest Science) ? Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, 2015. The aim of this study was to evaluate the application of Artificial Neural Networks (ANN) using the Skip-layer connections technique, with and without recurrence, to estimate the individual volume and total eucalyptus trees height. Its specific objectives were to test and evaluate reduction in the size of the adjustment assembly database (training) for estimating these variables. The data came from trees felled for scaling (estimation of individual volume) and measurements of permanent plots of continuous forest inventories (estimation of the total height), in eucalypt plantation area located in the south of Bahia, Brazil. Multilayer Perceptron (MLP) network type, using the logistic activation function in the intermediate and output layers and eight neurons in the hidden layer, were trained. The neurons number in the input layer varied according to the number and type of the variable (qualitative or quantitative) in each study. The stopping criteria were the root mean square error 0.0001 or 3,000 cycles (seasons). The software used for the RNA training and generalization was the NeuroForest 3.3. To compare the results obtained by RNA, traditional regression models were set for both the volume and the height, as well as RNA were trained and applied using the Resilient Propagation algorithm, commonly used in forest measurement applications. The evaluation of the results generated by the RNA and by the regression models was made via the correlation coefficient between observed and estimated values, scatter plots and histograms percentage frequency of the percentage errors. Artificial Neural Networks using Skip-layer connections showed satisfactory results for the estimation of volume and eucalyptus trees height, demonstrating the possibility of applying the technique in measuring and forest management and a significant reduction of databases for RNA training.
33

O problema da incerteza na medida no ensino médio: uma proposta para o ensino / The measurent uncertainty problem in high school: a proposal for teaching

Alves, Marcio José 08 April 2016 (has links)
O presente estudo aborda “o problema da incerteza na medida no ensino médio” e propõe uma Unidade de Ensino Potencialmente Significativo (UEPS) acerca do assunto. O objetivo desta proposta pedagógica é introduzir conceitos relativos às incertezas inerentes ao processo de medição, conhecimento visto como essencial para uma melhor compreensão dos experimentos quantitativos, e por consequência dos conceitos físicos. Participaram desse estudo alunos de Física do 1° ano do ensino médio do Colégio Estadual Professora Adélia Dionísia Barbosa, lotado no município de Londrina, no estado do Paraná. As principais constatações deste trabalho são: (i) é possível introduzir conceitos relativos às incertezas inerentes ao processo de medição, no ensino básico; (ii) as UEPS e a experimentação, alicerçadas por investigações da Educação Científica, que também abarcam o ensino de Física, podem contribuir para a aprendizagem significativa dos conceitos físicos e para a motivação dos alunos nas aulas de física do ensino médio. / This present study approach “the problem of uncertainty in the measure of the high school” and propose a Potentially Meaningful Teaching Unit (PMTU) about the matter. The objective of this pedagogical proposal is to introduce concept related to the uncertainties inherent to the measurement processes, knowledge considered essential for a better understanding of the quantitative experiments. Participants of this study were Physics students from the 1st year of high school at the Adélia Dionísia Barbosa State School, in Londrina, Paraná State. The main findings of this study are: (i) it is possible to introduce concepts related to the uncertainties inherent in the measurement process in basic education; (ii) the PMTU and the experimentation, based on scientific education research, which also includes physics teaching, can contribute to the meaningful learning of the physical concepts and to the motivation of students in high school physics classes.
34

Análise cinemática das distâncias percorridas de jogadores de basquetebol de elite / Kinematic analysis of distance covered of basketball elite players

Panhan, Ana Carolina, 1988- 25 August 2018 (has links)
Orientador: Luciano Allegretti Mercadante / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-25T19:10:30Z (GMT). No. of bitstreams: 1 Panhan_AnaCarolina_M.pdf: 2757563 bytes, checksum: ebeb8e5b5eaeca1eea6e2be60ecf9616 (MD5) Previous issue date: 2014 / Resumo: Um dos aspectos importantes nos estudos recentes com basquetebol é a descrição da movimentação dos jogadores, dada pela sua posição em função do tempo, que permite obter as distâncias percorridas e caracterizar o volume dos deslocamentos realizados pelos jogadores durante os jogos. Os objetivos desse trabalho foram: a) analisar as distâncias percorridas pelos jogadores por período de jogo e por jogo, as velocidades médias dos jogadores em bola viva (cronometro ativo) e bola morta (cronometro parado) por período de jogo e por jogo, b) analisar as distâncias percorridas entre as diferentes funções na equipe e verificar as distâncias percorridas pelos jogadores separados por função na equipe em situações de ataque, defesa e transições de ataque e de defesa e c) realizar a Análise por Componentes Principais dos jogadores separados por função, também em situações de ataque, defesa e transições de ataque e de defesa. O sistema DVideo (FEF-Unicamp, Campinas, Brasil) foi usado para obter as distâncias percorridas pelos jogadores de cinco equipes de basquetebol (A, B, C, D e E) em quatro jogos do Novo Basquete Brasil 2011/2012. Os alas-pivôs e pivôs da equipe (A) percorreram uma menor distância se comparados com os outros jogadores durante os quatro jogos analisados, o jogo 2 apresentou um menor valor de distância percorrida se comparado com os outros três jogos pois a duração do mesmo foi inferior aos outros e o último período (quarto) de jogo apresenta valores de distâncias percorridas superiores em relação ao outros períodos (quartos de jogo) pois a duração do mesmo é maior. Tanto para a equipe da casa (A), como para as equipes adversárias (B, C, D e E) foram encontradas diferenças significativas para os valores de distância percorrida entre as situações de jogo de ataque e defesa se comparadas com as transições, tanto de ataque como de defesa, os jogadores tem um maior deslocamento nas transições. Em situação de defesa todas as equipes não apresentaram diferença significativa para a variável excentricidade o que indica que os jogadores em situação de defesa se deslocam mais nas direções látero-laterais da quadra. Na situação de defesa as direções dos eixos principais são próximas as direções transversais da quadra. Os resultados apresentados são ferramentas importantes para técnicos e preparadores físicos de equipes de basquetebol porque ajudam a definir e detalhar o perfil físico e tático individual e coletivo dos jogadores e da equipe / Abstract: One important aspect in recent studies regarding basketball is the description of the players¿ movements as a function of time considering their different positions (i.e., distances covered and displacement velocity), which provides the characterization of volumes and intensities of the efforts made by the players during the games. The aim of this study were: a ) to analyze the distances the players for a period of play and per game average speeds of the live-ball players (active timer ) and dead ball ( timer stopped ) per period of play per game, b ) analyze the distances between the different roles in the team and check the distances the function separated by the team in situations of attack , defense and transitions attack and defense players and c ) perform principal component analysis of the function separated by players , also in case of attack, defense and transitions attack and defense . The Dvideo (FEF - Unicamp , Campinas , Brazil) system was used to obtain the distances the players five basketball teams ( A, B , C , D and E ) in four games Basketball New Brazil 2011/2012 . The power forwards and centers of the team (A) traveled a shorter distance compared to other players during the four games analyzed, Game 2 showed a lower amount of distance traveled when compared with the other three games because its duration was inferior to others and the last period (fourth) game presents higher values of distances traveled compared to other periods (quarters of play) because its duration is greater. So much for the home team (A) , as for the opposing teams ( B , C , D and E ) were significant for values of distance between the situations of the game of attack and defense differences compared with the transitions of attack and defense, players have a greater shift in the transitions. In defense situation all teams showed no significant difference to the eccentricity variable indicating that the players on defense situation moving in directions lateral- most side of the court. In defense situation the directions of the principal axes are near the transverse directions of the court. The results presented are important for coaches and trainers of basketball teams tools because they help define and detail the physical profile and individual and collective tactical players and team / Mestrado / Biodinâmica do Movimento Humano e Esporte / Mestra em Ciências da Nutrição e do Esporte e Metabolismo
35

Tree Profile Equations for Black Walnut (Juglans nigra L.) and Green Ash (Fraxinus Pennsylvanica) in Mississippi

Beard, Jacob R 17 August 2013 (has links)
Black walnut (Juglans nigra L.) is a valued, Mississippi tree species with very little published mensurational data. Tree profile equations are effective tree volume predictors but are typically developed from measurements on destructively sampled trees, an impractical method on valuable species. This study developed black walnut and green ash (Fraxinus pennsylvanica) profile equations from non-destructive measurements using a Barr & Stroud FP15 optical dendrometer. Accuracy of the dendrometer was validated by taking both optical dendrometer and felled, direct measurements on green ash trees. Two profile models were evaluated for measured tree data. Separate equations were created from optical dendrometer tree profile data for black walnut and green ash and felled tree profile data for green ash. The Barr & Stroud allowed tree profile equations to be developed from standing tree measurements with acceptable accuracy, thus providing useful tools towards the valuation and management of southeastern black walnut and green ash.
36

Temporal Organization in the Masses of Johannes Ockeghem

Farina, Andrew J. 29 December 2014 (has links)
No description available.
37

Estimating forest attributes using laser scanning data and dual-band, single-pass interferometric aperture radar to improve forest management

Peduzzi, Alicia 27 September 2011 (has links)
The overall objectives of this dissertation were to (1) determine whether leaf area index (LAI) (Chapter 2), as well as stem density and height to live crown (Chapter 3) can be estimated accurately in intensively managed pine plantations using small-footprint, multiple-return airborne laser scanner (lidar) data, and (2) ascertain whether leaf area index in temperate mixed forests is best estimated using multiple-return airborne laser scanning (lidar) data or dual-band, single-pass interferometric synthetic aperture radar data (from GeoSAR) alone or both in combination (Chapter 4). In situ measurements of LAI, mean height, height to live crown, and stem density were made on 109 (LAI) or 110 plots (all other variables) under a variety of stand conditions. Lidar distributional metrics were calculated for each plot as a whole as well as for crown density slices (newly introduced in this dissertation). These metrics were used as independent variables in best subsets regressions with LAI, number of trees, mean height to live crown, and mean height (measured in situ) as the dependent variables. The best resulting model for LAI in pine plantations had an R2 of 0.83 and a cross-validation (CV) RMSE of 0.5. The CV-RMSE for estimating number of trees on all 110 plots was 11.8 with an R2 of 0.92. Mean height to live crown was also well-predicted (R2 = 0.96, CV-RMSE = 0.8 m) with a one-variable model. In situ measurements of temperate mixed forest LAI were made on 61 plots (21 hardwood, 36 pine, 4 mixed pine hardwood). GeoSAR metrics were calculated from the X-band backscatter coefficients (four looks) as well as both X- and P-band interferometric heights and magnitudes. Both lidar and GeoSAR metrics were used as independent variables in best subsets regressions with LAI (measured in situ) as the dependent variable. Lidar metrics alone explained 69% of the variability in temperate mixed forest LAI, while GeoSAR metrics alone explained 52%. However, combining the LAI and GeoSAR metrics increased the R2 to 0.77 with a CV-RMSE of 0.42. Analysis of data from active sensors shows strong potential for eventual operational estimation of biophysical parameters essential to silviculture. / Ph. D.
38

Early Height Growth in Douglas Fir

Ferguson, C. W., Jr. 01 1900 (has links)
No description available.
39

A Revised Computer Program for Standardizing Tree-Ring Series

Fritts, Harold C., Mosimann, James E., Bottorff, Christine P. 03 1900 (has links)
No description available.
40

Noggrannhet och precision vid beståndsuppskattning av mobilapplikationen KATAM / Accuracy and precision in stand measurements of the mobile application KATAM

Andersson, Erik January 2019 (has links)
Syftet med arbetet var att utvärdera mobilapplikationen KATAM avseende noggrannhet, tidsåtgång, precision och praktisk användning i jämförelse med volymuppskattning med dataklave och skördarrapport. Resultatet vid diameterjämförelsen visar på snarlika uppskattningar från KATAM respektive dataklaven. KATAM hade högre medelgrundyta, 7 % och grövre medeldiameter, 3,7 %, i jämförelse med dataklaven. KATAM hade även överskattningar av medelstammen volym i jämförelse med skördarrapporten och dataklaven, från 2,5 % till 17,6 % beroende på vilket urval av provytor och vilken programversion av KATAM som användes. Underlaget från volymuppskattningar var litet och hade felkällor vilket gjorde resultaten från mätningarna osäkra. Trots att studien visade på en överskattning av diametern talar den inbördes precisionen för att KATAM skulle kunna bli ett alternativ till Dataklaven vid uppskattning av medeldiametern. / The purpose of this essay was to evaluate the mobile application KATAM of accuracy, time, precision and practical use in comparison to volume estimation with data Digital Caliper and harvester report. The result of the diameter comparison showed similar estimates from KATAM and the Digital Caliper respectively. KATAM had a higher mean basel area, 7% and coarser mean diameter, 3.7%, compared to the Digital Caliper. KATAM also had overestimations in volume as compared to the harvesting report and the Digital Caliper concerning the mean stem, from 2.5% to 17.6%, depending on which sample areas were included and which version of KATAM was used. However, the basis of volume estimates was small and had error sources, which made the results of the measurements uncertain. Although the study shows an overestimation of the diameter, the mutual precision indicates that KATAM could be an alternative to the Digital Caliper when estimating the mean diameter.

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