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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.
91

Detecção da doença mela-das-sementes da braquiária em gramíneas forrageiras através de técnicas de sensoriamento remoto

Rosatti, José Carlos [UNESP] 23 February 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-23Bitstream added on 2014-06-13T19:27:43Z : No. of bitstreams: 1 rosatti_jc_me_prud.pdf: 4413126 bytes, checksum: 5ac8f38c862833923e7eac17a3667cba (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Imagens CCD/CBERS 2 nas bandas B2, B3 e B4, dos anos de 2004 e 2005, de Mirante do Paranapanema, SP (Brasil), foram transformadas em reflectância de superfície usando o modelo 5S de correção atmosférica e normalizadas radiometricamente tendo como base o trabalho desenvolvido por Hall et al. (1991). O objetivo foi caracterizar espectralmente áreas de pastagens de Brachiaria brizantha (Hoschst ex A. Rich) Stapt, em fase de florescimento, isentas e infectadas com a doença mela-das-sementes da braquiária, no sentido de possibilitar a sua detecção através da comparação entre os valores de FRBS - Fator de Reflectância Bidirecional de Superfície. Ao mesmo tempo, objetivou-se também, avaliar a eficácia das imagens CCD/CBERS-2 para a obtenção de respostas espectrais de pastagens. Os valores de reflectância de superfície foram comparados e analisados através da variação espectral existente entre as áreas sadias e doentes e os resultados indicaram que as principais diferenças foram a diminuição da reflectância na banda B3 e o aumento da reflectância na banda B4 nas áreas doentes. Diferenças significativas também foram constatadas pela comparação entre dados obtidos de imagens índices de vegetação NDVI e RVI. A metodologia empregada com o uso de imagens CCD/CBERS-2 mostrou-se eficaz para descriminar áreas infectadas com a doença. / CCD/CBERS 2 images in the spectral bands B2, B3 and B4 of the years 2004 and 2005, from Mirante do Paranapanema, SP (Brazil), were transformed in surface reflectance images using the model 5S of atmospheric correction and radiometrically normalized tends as base the work developed by Hall et al. (1991). The objective was characterize spectrally areas of pastures of Brachiaria brizantha (Hoschst ex A. Rich) Stapt, in your flowering phase, exempt and infected with the disease mela-das-sementes da braquiária, in the sense of making possible your detection through the comparison among the FRBS - Surface of Bidirectional Reflectance Factor values. At the same time, it was aimed at to evaluate the effectiveness of the CCD/CBERS-2 images for the obtaining of spectral response of pastures. The surface of reflectance values were compared and analyzed through the existent spectral variation between the healthy and diseased areas and the results they indicated that the main differences were the decrease of the reflectance in the band B3 and the increase of the reflectance in the band B4 in the diseased areas. Significant differences were also verified by the comparison among obtained of vegetation indexes NDVI and RVI data. The methodology used with the use of CCD/CBERS-2 images it was shown effective for discrimination the areas infected with the disease.
92

Isolamento e avaliação da atividade nematicida de constituintes químicos de Mucuna aterrima / Isolation and evaluation of nematicidal activity of chemical constituents from Mucuna aterrima

Barcelos, Fernando Fontes 30 January 1997 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-08-29T16:54:45Z No. of bitstreams: 1 texto completo.pdf: 1098442 bytes, checksum: 07095a777150efd91c79dbe7fc816b43 (MD5) / Made available in DSpace on 2016-08-29T16:54:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1098442 bytes, checksum: 07095a777150efd91c79dbe7fc816b43 (MD5) Previous issue date: 1997-01-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As plantas do gênero Mucuna têm sido largamente utilizadas na agricultura, principalmente para eliminação de plantas daninhas, adubação verde e supressão da população de nematóides, levando à redução das aplicações de agroquímicos. Porém, poucos estudos fitoquímicos foram realizados com plantas deste gênero, e os compostos que conferem atividade nematicida a estas plantas ainda não foram caracterizados, apesar da reconhecida atividade e de sua vasta utilização. Em face disso, este trabalho teve por objetivo comprovar a eficiência da mucuna-preta (Mucuna aterrima) no controle do fitonematóide Meloidogyne incognita raça 3, através de ensaios biológicos in vitro com seu extrato bruto, bem como de realizar o estudo químico do caule e da raiz desta planta, buscando a identificação dos princípios ativos responsáveis pela atividade nematicida e, ou, nematostática. Assim, foram obtidos os extratos etanólicos a quente e a frio da raiz e da parte aérea da mucuna-preta, sendo estes submetidos a ensaios biológicos de atividade nematicida diante de Meloidogyne incognita raça 3. Todos os extratos apresentaram atividade de inibição da eclosão de ovos deste nematóide, e o extrato da raiz obtido a frio mostrou-se mais eficiente. Com base nesses resultados foram utilizados extratos etanólico do caule e etanólico e benzênico da raiz para o estudo químico. Estes foram submetidos a análises por CCD e fracionamentos sucessivos por cromatografia em coluna, proporcionando o isolamento dos seguintes compostos: do caule - KNO3 + NaNO3 (4,9 %, em massa), ácidos graxos e ésteres de ácidos graxos (6,2 %) e β-sitosterol + estigmasterol (0,5 %); e da raiz - KNO3 + NaNO3 (1,0 %), ácidos graxos (0,7 %), β-sitosterol + estigmasterol (2,8 %), alantoína (2,3 %), β-sitosterol glicosilado (daucosterol) + estigmasterol glicosilado (0,15 %) e, ainda, um álcool não-identificado (0,2 %). Estes compostos e os padrões de L-dopa, ácido caprílico, ácido palmítico, ácido esteárico, ácido linolênico, palmitato de metila e estearato de metila foram submetidos a ensaios biológicos, utilizando a técnica do tubo invertido. A análise dos resultados mostrou que os compostos, em uma concentração de 5 μg mL-1, que causaram maior mortalidade sobre juvenis de Meloidogyne incognita raça 3 foram o β-sitosterol + estigmasterol (74,4 % de mortalidade, em relação ao branco), o álcool não-identificado (69,7 %), KNO3 + NaNO3 (68,3 %) e a L-dopa (64,4 %). / Plants of genus Mucuna have been largely used in agriculture aiming at the elimination of weeds, green manuring and suppression of nematode populations, causing the agrochemicals applications to reduce. Just a few phytochemical studies have been carried out with plants of this genus and the compounds giving these plants nematicidal activity haven’t been yet characterized, although its recognized activity and large utilization. So, the objective of this work was to confirm the efficiency of velvetbean (Mucuna aterrima) in controlling the phytonematode Meloidogyne incognita strain 3, through the in vitro biological assays with its crude extract, as well as to conduct a chemical study on the stems and roots of this plant in order to identify the active principles responsible for nematostatic and/or nematicidal activity. The ethanolic extracts were obtained by a hot-and-cold process from roots and the aerial part of velvetbean. These extracts were submitted to biological assays for nematicidal activity on Meloidogyne incognita strain 3. All extracts were active in inhibiting eclosion of the juveniles’ eggs whereas the root extract, which was obtained by a cold process, showed to be more effective. Based on these results, it were used both ethanolic extracts from stems and the ethanolic and benzenic extracts from roots for chemical study. These extracts were submitted to TLC analysis and successive fractionation in column chromatography, providing the isolation of the following compounds: from stems - KNO3 + NaNO3 (4,9 %, in mass), fatty acids and esters of fatty acids (6,2 %) and β-sitosterol + stigmasterol (0,5 %); and from roots - KNO3 + NaNO3 (1,0 %), fatty acids (0,7 %), β- sitosterol + stigmasterol (2,8 %), allantoin (2,3 %), β-sitosterol-D(+)-glucoside (daucosterol) + stigmasterol-D(+)-glucoside (0,15 %) and also a no-identified alcohol (0,2 %). These compounds and the L-dopa, caprylic acid, palmitic acid, stearic acid, linolenic acid, methyl palmitate and methyl stearate standards were submitted to biological assays by the inverted tube method. The results analysis showed that compounds at a 5 μg mL-1 concentration, which caused a higher mortality on juveniles of Meloidogyne incognita strain 3, were β-sitosterol + stigmasterol (74,4% mortality relative to control), the no-identified alcohol (69,7 %), KNO3 + NaNO3 (68,3 %) and the L-dopa (64,4 %). / Não foi encontrado o cpf do autor.
93

Using multicoloured halftone screens for offset print quality monitoring

Bergman, Lars January 2005 (has links)
In the newspaper printing industry, offset is the dominating printing method and the use of multicolour printing has increased rapidly in newspapers during the last decade. The offset printing process relies on the assumption that an uniform film of ink of right thickness is transferred onto the printing areas. The quality of reproduction of colour images in offset printing is dependent on a number of parameters in a chain of steps and in the end it is the amount and the distribution of ink deposited on the substrate that create the sensation and thus the perceived colours. We identify three control points in the offset printing process and present methods for assessing the printing process quality in two of these points: • Methods for determining if the printing plates carry the correct image • Methods for determining the amount of ink deposited onto the newsprint A new concept of colour impression is introduced as a measure of the amount of ink deposited on the newsprint. Two factors contribute to values of the colour impression, the halftone dot-size and ink density. Colour impression values are determined on gray-bars using a CCD-camera based system. Colour impression values can also be determined in an area containing an arbitrary combination of cyan magenta and yellow inks. The correct amount of ink is known either from a reference print or from prepress information. Thus, the deviation of the amount of ink can be determined that can be used as control value by a press operator or as input to a control system. How a closed loop controller can be designed based on the colour impression values is also shown. It is demonstrated that the methods developed can be used for off-line print quality monitoring and ink feed control, or preferably in an online system in a newspaper printing press. / <p>Report code: LiU-TEK-LIC-2005:02</p>
94

Caracterização de uma matriz detectora cintiladora para aquisição de imagem 2D da região folicular da Glândula Tireóide por emissão radioativa usando simulação Monte Carlo

Silva, Carlos Borges da, Instituto de Engenharia Nuclear 05 1900 (has links)
Submitted by Marcele Costal de Castro (costalcastro@gmail.com) on 2017-09-11T17:25:50Z No. of bitstreams: 1 CARLOS BORGES DA SILVA D.PDF: 1636870 bytes, checksum: add9dec83838e16e49de59dc37b07783 (MD5) / Made available in DSpace on 2017-09-11T17:25:50Z (GMT). No. of bitstreams: 1 CARLOS BORGES DA SILVA D.PDF: 1636870 bytes, checksum: add9dec83838e16e49de59dc37b07783 (MD5) Previous issue date: 2007-05 / Os métodos de aquisição de imagem utilizados em medicina nuclear e na radiobiologia são valiosos na determinação da anatomia da glândula tireóide na busca de anormalidades associadas ao comportamento das células foliculares. A simulação baseada no método Monte Carlo (MC) também tem sido muito utilizada na solução de problemas relacionados à detecção da radiação visando o mapeamento de imagens médicas desde a evolução da capacidade de processamento dos computadores pessoais (PC). Este trabalho apresenta um estudo inovador para encontrar o tipo adequado de matriz cintiladora, que uma vez acoplada a um dispositivo CCD (Charge Coupled Device) através de uma placa de fibra ótica, pode ser aplicado no mapeamento de imagens de folículos da glândula tireóide. A metodologia utiliza a técnica de imageamento por emissão gama e a simulação MC, visando o desenvolvimento de um sistema capaz de obter uma imagem com resolução espacial de 10 m e boa eficiência do detector. A simulação do conjunto fonte-detector foi realizada por meio do programa MCNP4B (Monte Carlo para nêutron próton transporte) para diferentes energias, materiais detectores e geometrias, incluindo tamanho de “pixel” e tipos de materiais refletores. Os resultados alcançados mostram que utilizando o MCNP4B é possível estudar e avaliar parâmetros úteis relacionados aos sistemas utilizados em medicina nuclear, especificamente em radiobiologia aplicada a estudos da fisiologia endócrina no mapeamento de imagens de folículos tireoideanos. / The image acquisition methods applied to nuclear medicine and radiobiology are a valuable research study for determination of thyroid anatomy to seek disorders associated to follicular cells. The Monte Carlo (MC) simulation has also been used in problems related to radiation detection in order to map medical images since the improvement of data processing compatible with personnel computers (PC). This work presents an innovative study to find out the adequate scintillation inorganic detector array that could be coupled to a specific light photo sensor, a charge coupled device (CCD) through a fiber optic plate in order to map the follicles of thyroid gland. The goal is to choose the type of detector that fits the application suggested here with spatial resolution of 10 m and good detector efficiency. The methodology results are useful to map a follicle image using gamma radiation emission. A source - detector simulation is performed by using a MCNP4B (Monte Carlo for Neutron Photon transport) general code considering different source energies, detector materials and geometries including pixel sizes and reflector types. The results demonstrate that by using MCNP4B code is possible to searching for useful parameters related to the systems used in nuclear medicine, specifically in radiobiology applied to endocrine physiology studies to acquiring thyroid follicles images.
95

In-orbit performance analysis of the image sensors from Pleiades mission

Romero, Faviola January 2017 (has links)
The image sensors embedded in the instruments on board of different satellites are a key aspect in the success of a mission of any type such as Earth observation, astronomy or planetary and universe exploration. The quality of the sensor itself as well as the electronics embedded in the instrument suffer from aging, not only due to the usage, but also due to the space environment factors. The outer space harsh environment is composed of charged particles with an incredibly high energy that can get through the shielding of the spacecraft thus causing damage to the sensors, or any part of the spacecraft. After a satellite is placed in orbit, there is no other way to check on its condition than to analyse the data transmitted to the ground stations.   It is well known that we can measure the evolution of the instrument’s detection unit by measuring the variation of the quality of the images taken in orbit. As it has been done in past work, the atypical behaviour can be detected at a pixel level by analysing the images taken in orbit, preferably in complete darkness to discard any parasitic light. Past analysis of the dark images from the sensors on board the Picard, SPOT4 and Sentinel2A mission, proposed a classification of the different atypical behaviour that a pixel can show, such as hot, transitory-hot or RTS. By the end of the mission this defects may even be present in several pixels.   The purpose of this work is to process the dark images obtained on orbit, at the end of the mission PLEIADES, to better understand the behaviour both Panchromatic and Multispectral CCD sensors and the differences in performance with respect to the tests made previously on ground. For this, a description of the framework of the PLEIADES mission and the technical design aspects of the CCD sensors on board are presented. Subsequently, the different image processing techniques used and developed are described, along with the tests made to get to the positive conclusion of no major anomalies detected in the PLEIADES images sensors. The analysis is done by means of new set of functions adjusted to the structure of the data, as well as the same detection software used in the previous analysis. Finally, a discussion is presented along with a further perspective for the analysis of future sets of data.
96

A Software Model for MATS Satellite Payload

Seth, Tejaswi January 2018 (has links)
This thesis presents the development of a software model that simulates a payload instrument onboard the MATS satellite. The goal of this model is to provide an understanding of how the instrument impacts the measured data. This model is important for error analysis and may help in correcting the measured data for systematic flaws in the instrument. The software will consist of 5 main modules as follows: Scene Generator, Optics Module,Stray Light Module, Charge-Coupled Device Module and Electronics Module. This thesis forms a basic foundation for the software by designing the CCD module and a part of the Optics module, and concludes the effects of both on the output of the system. It takes into account important mission defined procedures that ultimately aim to improve image quality, resolve vertical structures in different bandwidths and analyze noise effects on the measured data.
97

Čtečka Braillova písma / Braille Reader

Zapletal, Pavel January 2012 (has links)
The aim of work is conversion of a photographed Braille into ordinary text. On the beginning, there are described Braille specification and principles. In the next part are mentioned types of sensors for taking photos. The main part describes phases of image processing and their implementation in C++. At the end, there are listed possibilities of future development.
98

Bestimmung der Drahtvorschubgeschwindigkeit beim MIG/MAG-Schweißen mittels berührungsloser Messverfahren

Kohler, Thomas 03 May 2004 (has links)
System zur berührungslosen Drahtvorschubgeschwindigkeitsmessung mittels CCD-Kameramodul. Die Auswertung der Daten wird mittels Wavelet-Algorithmen durchgeführt.
99

Användarcentrerad design och utvärdering av en barnbokapp för inlärning av känslor och empati genom social interaktion / User-centered design and evaluation of a children's book app through social interaction

Ericsson, Niclas January 2016 (has links)
Med dagens teknik kan traditionella bilderböcker för barn återskapas i form av interaktiva applikationer. Detta gör att digitala element som animationer och ljudeffekter kan implementeras för att förstärka berättelsens budskap. Detta öppnar också upp för intressanta forskningsfrågor kring hur sådana applikationer, och deras interaktiva funktioner, bör utformas i den givna kontexten. I den här studien undersöks hur utformningen av en barnbokapplikation, med fokus på inlärning av känslor och empati, kan påverka den sociala interaktionen mellan den vuxna läsaren och barnet. För att förstå hur utformning av barnböcker och barnbokappar påverkar den sociala interaktionen under högläsning utfördes en omfattande teori- och litteraturstudie inom dessa områden. En state-of-the-art-analys utfördes även för att studera den nuvarande marknaden av barnbokappar. Detta ledde fram till studiens frågeställning: Vilka interaktiva element i en barnbokapplikation bidrar till ökad relevant social interaktion, och därmed uppmuntrar till inlärning av känslor och empati, mellan barn och vuxen? Frågeställningen undersöktes genom att en barnbokapp, baserad på barnboken ”Sammy hjälper till”, utvecklades och testades i en användarstudie där tre användartest utfördes; två test på förskolor i Stockholm och ett test där ett antal småbarnsfamiljer fick testa appen i hemmet under en veckas tid. Den utvecklade barnbokappen bestod av tre huvudsakliga interaktiva funktioner; diskussionsfrågor, interaktiva karaktärer och interaktiva områden. Resultaten visade att diskussionsfrågorna var de som bidrog mest till ökad social interaktion mellan barnet och den vuxne läsaren. De andra funktionerna varierade mer i hur de påverkade den sociala interaktionen och behöver därför utforskas vidare. En tydlig slutsats från studien är att det finns många viktiga faktorer att tänka på vid design och utformning av en barnbokapp med fokus på känslor och empati. Den sociala kontexten är viktig att tänka vid utformning av en app, liksom det åldersspann som appen är tänkt att riktas mot. Slutligen presenteras förslag på fortsatt forskning inom området. / With modern technology, traditional picture books for children can be recreated in the form of interactive applications. This opens up the possibility of implementing digital elements like animations and sound effects to reinforce the message of the story. This also opens up interesting research questions about how these applications, and their interactive features, should be designed in the given context. This study examines how the design of a children's book app (short for application), focusing on teaching and understanding emotions and empathy, can affect the social interaction between the adult reader and the child. A comprehensive literature study was conducted in order to understand how the design of picture books and book apps affects the social interaction during reading sessions. A state-of-the-art analysis was also conducted to study the current state of children’s book apps. This led to the main research question of the study: Which interactive elements in a children's book app help increase the relevant social interaction between child and adult? A children’s book app based on the Swedish picture book “Sammy helps out” was developed and tested in a user study where three user tests were conducted; two tests in preschool facilities in Stockholm and one test where a number of families with small children were asked to test the app in their homes for a week. The developed app consisted of three main interactive features called “discussion questions”, “interactive characters” and “interactive areas”. The results showed that the discussion questions were the largest contributors to increased social interaction between the child and the adult reader. The other functions were more varied in how they affected the social interaction and therefore need to be explored further. A conclusion from the study is that there are many important factors to consider in the design of a children’s book app focusing on emotions and empathy. The social context is important to keep in mind while designing an app, as well as the age range that the app is supposed to be marketed towards. Finally, suggestions for further research in the area are presented.
100

Most efficient Inverse Kinematics algorithm for Quadruped models : Comparing FABRIK to CCD

Richardsson, Matilda January 2022 (has links)
This paper compares the two heuristic inverse kinematics methods: Forward And Backward Reaching Inverse Kinematics (FABRIK) and Cyclic Coordinate Descent (CCD) in the use cases concerning quadruped models. Unoptimised versions of the two algorithms were implemented into a game engine and evaluated on a quadruped model. The two algorithms were evaluated by computational time, iterations and average error. The results show that FABRIK outperformed CCD in all of our test scenarios, in number of iterations required, average error as well as function execution time. However, results also showed that FABRIK was less superior when targets were barely within reach, since one leg might be able to reach a target, but two connected legs might not be able to reach two targets because of their interference with each other. This suggests that to improve on FABRIK it should be optimised when considering a bipedal or quadruped model. / Den här artikeln jämför de två heuristiska Inverse Kinematics-metoderna: Forward And Backward Reaching Inverse Kinematics (FABRIK) och Cyclic Coordinate Descent (CCD) i användningsfallet fyrbenta modeller. Ooptimerade versioner av de två algoritmerna implementerades i en spelmotor och utvärderades på en fyrbent modell. De två algoritmerna utvärderades därefter baserat på beräkningstid, antal iterationer och avstånd till målet. Resultaten visar att FABRIK överträffade CCD i alla testscenarium, i antal iterationer, avstånd till mål samt funktionskörningstid. Resultaten visade dock även att FABRIK var mindre överlägsen när målen var precis utom räckhåll; detta då ett ben kunde nå ett mål om det utvärderades ensamt, men när benet kopplades samman med motstående ben via en höftled kunde inget av benen nå sina mål på grund av att de påverkade varandra. Detta tyder på att för att förbättra FABRIK bör den optimeras till att ta hänsyn till huruvida modellen har två eller fyra ben.

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