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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.
1

Development of a MALDI-Ion Mobility-Surface-Induced Dissociation-Time-of-flight-mass spectrometer for the analysis of peptides and proteins

Stone, Earle Gregory 30 September 2004 (has links)
Peptide sequencing by surface-induced dissociation (SID) on a MALDI-Ion Mobility-orthogonal-TOF mass spectrometer is demonstrated. The early version of the instrument used for proof-of-concept experiments achieves a mobility resolution of approximately 20 and TOF mass resolution better than 200. Peptide sequences of four peptides from a tryptic digest of cytochrome c (ca. 1 pmol deposited) were obtained. The advantage of IM-SID-o-TOFMS is that a single experiment can be used to simultaneously measure the molecular weights of the tryptic peptide fragments (peptide mass mapping) and partial sequence analysis, (real time tandem mass spectrometry.) Optimization of the MALDI-IM-SID-o-TOF mass spectrometer for peptide sequencing is discussed. SID spectra obtained by using stainless steel, Au grids, and fluorinated self-assembled monolayers (F-SAM) on Au are compared. Optimum collision energies differ for the various surfaces. The fragmentation patterns observed for a series of peptides and protein digests using the Nd:YAG laser (355 nm) for MALDI ion formation and an FSAM surface for ion activation is compared to the fragmentation patterns observed for CID and photodissociation. The fragmentation patterns observed in all cases are strikingly similar. Photodissociation produced a greater abundance of ions resulting from side-chain cleavages. As a general rule optimized SID spectra contain fewer immonium ions than either photodissociation or CID. Evaluation of an instrument incorporating a new hybrid drift cell is discussed. Spectra for a digest of hemoglobin is compared to that acquired with an ABI 4700 TOF-TOF. The performance of the instrument is also evaluated using a micro-crystal Nd:YAG laser (355 nm) for MALDI operated at 400 Hz. Experiments were performed to determine the sensitivity and overall performance of the instrument. The reproducibility of the MS/MS spectra for gramicidin S is shown to be 94% run-to-run. The best mobility resolution obtained for a neat deposition of the dye Crystal Violet was 60 t/∆t. Sensitivity was tested with the peptide fibrinopeptide A (m/z 1537, AA sequence ADSGEGDFLAEGGGVR). Data acquired for sixty seconds with approximately sixty femtomoles deposited. Abundant [M+H]+ ions where observed as well as [M+H]+-NH3 ions. The S/N for this short run was insufficient to identify any SID fragments
2

Conceptual Product Development in Small Corporations

Nilsson, Per January 2010 (has links)
The main objective of the thesis “Conceptual Product Development in Small Corporations” is by the use of a case study test the MFD™-method (Erixon G. , 1998) combined with PMM in a product development project. (Henceforth called MFD™/PMM-method). The MFD™/PMM-method used for documenting and controlling a product development project has since it was introduced been used in several industries and projects. The method has been proved to be a good way of working with the early stages of product development, however, there are almost only projects carried out on large industries which means that there are very few references to how the MFD™/PMM-method works in a small corporation. Therefore, was the case study in the thesis “Conceptual Product Development in Small Corporations” carried out in a small corporation to find out whether the MFD™/PMM-method also can be applied and used in such a corporation.The PMM was proposed in a paper presented at Delft University of Technology in Holland 1998 by the author and Gunnar Erixon. (See appended paper C: The chart of modular function deployment.) The title “The chart of modular function deployment” was later renamed as PMM, Product Management Map. (Sweden PreCAD AB, 2000). The PMM consists of a QFD-matrix linked to MIM (Module Indication Matrix) via a coupling matrix which makes it possible to make an unbroken chain from the customer domain to the designed product/modules. The PMM makes it easy to correct omissions made in creating new products and modules.In the thesis “Conceptual Product Development in Small Corporations” the universal MFD™/PMM-method has been adapted by the author to three models of product development; original-, evolutionary- and incremental development.The evolutionary adapted MFD™/PMM-method was tested as a case study at Atlings AB in the community Ockelbo. Atlings AB is a small corporation with a total number of 50 employees and an annual turnover of 9 million €. The product studied at the corporation was a steady rest for supporting long shafts in turning. The project team consisted of management director, a sales promoter, a production engineer, a design engineer and a workshop technician, the author as team leader and a colleague from Dalarna University as discussion partner. The project team has had six meetings.The project team managed to use MFD™ and to make a complete PMM of the studied product. There were no real problems occurring in the project work, on the contrary the team members worked very well in the group, having ideas how to improve the product. Instead, the challenge for a small company is how to work with the MFD™/PMM-method in the long run! If the MFD™/PMM-method is to be a useful tool for the company it needs to be used continuously and that requires financial and personnel resources. One way for the company to overcome the probable lack of recourses regarding capital and personnel is to establish a good cooperation with a regional university or a development centre.
3

Development of a MALDI-Ion Mobility-Surface-Induced Dissociation-Time-of-flight-mass spectrometer for the analysis of peptides and proteins

Stone, Earle Gregory 30 September 2004 (has links)
Peptide sequencing by surface-induced dissociation (SID) on a MALDI-Ion Mobility-orthogonal-TOF mass spectrometer is demonstrated. The early version of the instrument used for proof-of-concept experiments achieves a mobility resolution of approximately 20 and TOF mass resolution better than 200. Peptide sequences of four peptides from a tryptic digest of cytochrome c (ca. 1 pmol deposited) were obtained. The advantage of IM-SID-o-TOFMS is that a single experiment can be used to simultaneously measure the molecular weights of the tryptic peptide fragments (peptide mass mapping) and partial sequence analysis, (real time tandem mass spectrometry.) Optimization of the MALDI-IM-SID-o-TOF mass spectrometer for peptide sequencing is discussed. SID spectra obtained by using stainless steel, Au grids, and fluorinated self-assembled monolayers (F-SAM) on Au are compared. Optimum collision energies differ for the various surfaces. The fragmentation patterns observed for a series of peptides and protein digests using the Nd:YAG laser (355 nm) for MALDI ion formation and an FSAM surface for ion activation is compared to the fragmentation patterns observed for CID and photodissociation. The fragmentation patterns observed in all cases are strikingly similar. Photodissociation produced a greater abundance of ions resulting from side-chain cleavages. As a general rule optimized SID spectra contain fewer immonium ions than either photodissociation or CID. Evaluation of an instrument incorporating a new hybrid drift cell is discussed. Spectra for a digest of hemoglobin is compared to that acquired with an ABI 4700 TOF-TOF. The performance of the instrument is also evaluated using a micro-crystal Nd:YAG laser (355 nm) for MALDI operated at 400 Hz. Experiments were performed to determine the sensitivity and overall performance of the instrument. The reproducibility of the MS/MS spectra for gramicidin S is shown to be 94% run-to-run. The best mobility resolution obtained for a neat deposition of the dye Crystal Violet was 60 t/∆t. Sensitivity was tested with the peptide fibrinopeptide A (m/z 1537, AA sequence ADSGEGDFLAEGGGVR). Data acquired for sixty seconds with approximately sixty femtomoles deposited. Abundant [M+H]+ ions where observed as well as [M+H]+-NH3 ions. The S/N for this short run was insufficient to identify any SID fragments
4

Aplicação de CFD para obtenção de derivadas hidrodinâmicas de embarcações em condição de manobra. / Application of CFD in order to obtain hydrodynamic derivatives of vessels in maneuvering condition.

Gallina, André de Farias 08 December 2014 (has links)
O aumento do uso de códigos numéricos baseados em dinâmica de fluidos computacional (CFD) atrelado a problemas de engenharia naval e a necessidade de se estabelecer a proximidade dos resultados obtidos nas simulações com os experimentos físicos serviu de motivação para execução deste trabalho. O tema do presente trabalho é pertinente uma vez que o número de trabalhos publicados que simulam com precisão ensaios de embarcações em condição de manobra e obtêm as derivadas hidrodinâmicas que caracterizam o movimento é muito pequeno, atendendo assim a uma demanda existente por novas confrontações numérico/experimentais. Com isso, um conjunto de ensaios de PMM (Planar Motion Mechanism), mais especificamente os ensaios de sway e yaw puros e yaw com drift, e arrasto oblíquo foram executados na embarcação KVLCC2, nas condições de manobra, similares aos ensaios realizados pelo laboratório italiano ISEAN que tinha por objetivo fornecer uma base de comparação para trabalhos em CFD. Os resultados das forças e momentos das simulações foram comparados com os obtidos nos ensaios, bem como as derivadas hidrodinâmicas que caracterizam a embarcação estudada. De maneira geral, os resultados obtidos nas simulações mostraram-se muito próximos aos obtidos a partir do ensaio, fornecendo assim um bom resultado nas derivadas hidrodinâmica, principalmente com relação às derivadas em função das velocidades de translação e rotação. Na expectativa de ampliar a aplicação do método de solução proposto, um novo conjunto de simulações foi realizado na escala real da embarcação. As dificuldades encontradas devido às incompatibilidades nos números de Reynolds mostraram-se presentes, de maneira similar às encontradas nos ensaios físicos evidenciando inclusive que o fator de forma está diretamente atrelado ao número de Reynolds, contrariando a hipótese clássica e alinhando-se com trabalhos mais recentes publicados sobre o tema. Os resultados encontrados a partir da aplicação da metodologia mostram coerência em relação às respostas encontradas nos ensaios, fornecendo uma alternativa ao método clássico de obtenção das características hidrodinâmicas de uma embarcação de superfície em condição de manobra. Ainda fornece uma opção de cálculos, que ainda necessita de melhorias e validação mais elaborada, nas condições da escala real, fato impossível sem o uso de simulações. / The growing use of numerical codes based on computational fluid dynamics (CFD) in problems related with marine engineering and the need to establish the reliability of the results from the simulations with those derived from physical tests served as the motivation for performing the work. The subject of this work is relevant since the number of published works that accurately simulate and test the conditions of vessels in maneuvering and obtains the hydrodynamic derivatives that characterize the movement is very small, thus meeting an existing demand for the new numeric confrontations / experimental. Therefore, a set of PMM tests (Planar Motion Mechanism), more specifically: pure sway, pure yaw and yaw whit drift, and static drift, were performed on the vessel KVLCC2 under conditions of maneuver, similar to tests conducted by the Italian laboratory ISEAN which was intended to provide a basis of comparison for work with CFD. The results of the forces and moments of simulations were compared with those from the tests, as well as the hydrodynamic derivatives which characterize the vessel studied. In general, the results from simulations were very close to those from the experiment, thus providing a good result in hydrodynamic, derived primarily related to derivatives, depending on the speed of translation and rotation. Expecting to expand the application of the proposed method, a new solution set of simulations was carried out in a full-scale vessel. The difficulties encountered due to incompatibilities in the Reynolds numbers were similarly found in the physical testing. This included demonstrating the form factor directly linked to the Reynolds number, contrary to the classical hypothesis and aligning with the latest publications on the subject. The results from the application of the methodology show consistency with the solutions found in the tests, providing an alternative to the classical method of obtaining the hydrodynamic characteristics of a surface vessel in a condition of maneuver. We also provide an option of calculations, which still needs improvement and a more elaborate validation under full-scale conditions, which would be impossible without the use of simulations.
5

Aplicação de CFD para obtenção de derivadas hidrodinâmicas de embarcações em condição de manobra. / Application of CFD in order to obtain hydrodynamic derivatives of vessels in maneuvering condition.

André de Farias Gallina 08 December 2014 (has links)
O aumento do uso de códigos numéricos baseados em dinâmica de fluidos computacional (CFD) atrelado a problemas de engenharia naval e a necessidade de se estabelecer a proximidade dos resultados obtidos nas simulações com os experimentos físicos serviu de motivação para execução deste trabalho. O tema do presente trabalho é pertinente uma vez que o número de trabalhos publicados que simulam com precisão ensaios de embarcações em condição de manobra e obtêm as derivadas hidrodinâmicas que caracterizam o movimento é muito pequeno, atendendo assim a uma demanda existente por novas confrontações numérico/experimentais. Com isso, um conjunto de ensaios de PMM (Planar Motion Mechanism), mais especificamente os ensaios de sway e yaw puros e yaw com drift, e arrasto oblíquo foram executados na embarcação KVLCC2, nas condições de manobra, similares aos ensaios realizados pelo laboratório italiano ISEAN que tinha por objetivo fornecer uma base de comparação para trabalhos em CFD. Os resultados das forças e momentos das simulações foram comparados com os obtidos nos ensaios, bem como as derivadas hidrodinâmicas que caracterizam a embarcação estudada. De maneira geral, os resultados obtidos nas simulações mostraram-se muito próximos aos obtidos a partir do ensaio, fornecendo assim um bom resultado nas derivadas hidrodinâmica, principalmente com relação às derivadas em função das velocidades de translação e rotação. Na expectativa de ampliar a aplicação do método de solução proposto, um novo conjunto de simulações foi realizado na escala real da embarcação. As dificuldades encontradas devido às incompatibilidades nos números de Reynolds mostraram-se presentes, de maneira similar às encontradas nos ensaios físicos evidenciando inclusive que o fator de forma está diretamente atrelado ao número de Reynolds, contrariando a hipótese clássica e alinhando-se com trabalhos mais recentes publicados sobre o tema. Os resultados encontrados a partir da aplicação da metodologia mostram coerência em relação às respostas encontradas nos ensaios, fornecendo uma alternativa ao método clássico de obtenção das características hidrodinâmicas de uma embarcação de superfície em condição de manobra. Ainda fornece uma opção de cálculos, que ainda necessita de melhorias e validação mais elaborada, nas condições da escala real, fato impossível sem o uso de simulações. / The growing use of numerical codes based on computational fluid dynamics (CFD) in problems related with marine engineering and the need to establish the reliability of the results from the simulations with those derived from physical tests served as the motivation for performing the work. The subject of this work is relevant since the number of published works that accurately simulate and test the conditions of vessels in maneuvering and obtains the hydrodynamic derivatives that characterize the movement is very small, thus meeting an existing demand for the new numeric confrontations / experimental. Therefore, a set of PMM tests (Planar Motion Mechanism), more specifically: pure sway, pure yaw and yaw whit drift, and static drift, were performed on the vessel KVLCC2 under conditions of maneuver, similar to tests conducted by the Italian laboratory ISEAN which was intended to provide a basis of comparison for work with CFD. The results of the forces and moments of simulations were compared with those from the tests, as well as the hydrodynamic derivatives which characterize the vessel studied. In general, the results from simulations were very close to those from the experiment, thus providing a good result in hydrodynamic, derived primarily related to derivatives, depending on the speed of translation and rotation. Expecting to expand the application of the proposed method, a new solution set of simulations was carried out in a full-scale vessel. The difficulties encountered due to incompatibilities in the Reynolds numbers were similarly found in the physical testing. This included demonstrating the form factor directly linked to the Reynolds number, contrary to the classical hypothesis and aligning with the latest publications on the subject. The results from the application of the methodology show consistency with the solutions found in the tests, providing an alternative to the classical method of obtaining the hydrodynamic characteristics of a surface vessel in a condition of maneuver. We also provide an option of calculations, which still needs improvement and a more elaborate validation under full-scale conditions, which would be impossible without the use of simulations.
6

Effects of headwinds on towing tank resistance and PMM tests for ONR Tumblehome

Cook, Shane Stuart 01 December 2011 (has links)
Calm water towing tank experiments consisting of resistance tests and static and dynamic planar motion mechanism (PMM) tests are performed for a surface combatant with primary focus on the effects of hurricane scale headwinds. The experiments are designed to gain a better understanding of the physics of ship response to wind and to provide a validation dataset for an unsteady Reynolds-averaged Navier Stokes (RANS)-based computational fluid dynamics (CFD) code used for computing both air and water flow around a ship. Hurricane scale wind speeds are chosen to maximize the measurable effect of wind on ship forces and motions for a more definitive analysis and comparison with CFD. The geometry is the 1/48.9 scale fully appended ONR Tumblehome model 5613, which has length L = 3.147 m and is equipped with a superstructure. Tests are performed in a 3.048 × 3.048 × 100 m towing tank with wind generated by a custom built wind carriage towed ahead of the ship model. Air-stream velocity measurements indicate a maximum relative wind speed magnitude of 9.38 m/s with 6 - 7% uniformity and RMS values of approximately 4.5%. The effects of three wind speeds on static and dynamic forces, moment, and motions are analyzed. Results show that wind contributes significantly to surge force (approximately 46% at Fr = 0.2). Resistance data shows agreement with CFD computations with errors averaging approximately 4%. The drag coefficient above water is approximately 0.3 and generally decreases with increasing ship speed. Sway force and yaw moment are largely affected when the ship experiences oblique orientation to the flow. Forces and moment exhibit quadratic scaling with wind speed. Roll is the most sensitive motion to wind and is counteracted by it up to 1.8° for PMM test conditions. In addition, harmonic amplitudes of forces and moment data from dynamic tests are used to determine hydrodynamic derivatives for all three wind conditions following a mathematical model. The effect of wind on hydrodynamic derivatives is significant with changes on the order of 10 - 100%.
7

Phase-averaged stereo-PIV flow field and force/moment/motion measurements for surface combatant in PMM maneuvers

Yoon, Hyunse 01 December 2009 (has links)
Towing-tank experiments are performed for a surface combatant as it undergoes static and dynamic planar motion mechanism maneuvers in calm water. The data includes global forces/moment/motions and phase-averaged local flow-fields, and uncertainty assessment. The geometry is DTMB model 5512, which is a 1/46.6 scale geosym of DTMB model 5415, with L = 3.048 m. The experiments are performed in a 3.048 × 3.048 × 100 m towing tank. The measurement system features a custom designed planar motion mechanism, a towed stereoscopic particle image velocimetry system, a Krypton contactless motion tracker, and a 6-component loadcell. The forces/moment and UA are conducted in collaboration with two international facilities (FORCE and INSEAN), including test matrix and overlapping tests using the same model geometry but with different scales. Quality of the data is assessed by monitoring the statistical convergence, including tests for randomness, stationarity, and normality. Uncertainty is assessed following the ASME Standards (1998 and 2005). Hydrodynamic derivatives are determined from the forces/moment data by using the Abkowitz (1966) mathematical model, with two different 'Multiple-Run (MR)' and 'Single-Run (SR)' methods. The results for reconstructions of the forces/moment indicate that usually the MR method is more accurate than the SR. Comparisons are made of the hydrodynamic derivatives across different facilities. The scale effect is small for sway derivatives, whereas considerable for yaw derivatives. Heave, pitch, and roll motions exhibit cross-coupling between the motions and forces and moment data, as expect based on ship motions theory. Hydrodynamic derivatives are compared between different mount conditions. Linear derivatives values are less sensitive to the mounting conditions, whereas the non-linear derivatives are considerably different. Phase-averaged flowfield results indicate maneuvering-induced vortices and their interactions with the turbulent boundary layer. The tests are sufficiently documented and detailed so as to be useful as benchmark EFD data for CFD validation.
8

Optimalių parametrų parinkimas, automatizuotam garsyno anotavimui, taikant paslėptų Markovo modelių metodiką / Selecting the most suitable parameters for automatic sound annotation by using hidden Markov models method

Štrimaitis, Kęstutis 11 August 2009 (has links)
Magistrinio darbo tikslas buvo nustatyti optimalias parametrų reikšmes automatizuotam garsyno anotavimui, taikant paslėptų Markovo modelių metodiką. Tyrime buvo nagrinėjami 25 skirtingų kalbėtojų įrašai. Kiekvienam kalbėtojui buvo naudojama po 60min įrašų apmokymams ir vienas 2min įrašas buvo naudojamas testavimui. Buvo atliekami keturių tipų eksperimentai pavadinti: PMM modelių apjungimas, PMM tikslinimų skaičius, visų Gauso mišinių įterpimas iškarto, Gauso mišinių įterpimas mišinių skaičių didinat po vieną. Kad palengvinti eksperimentų atlikimą ir rezultatų nagrinėjimą buvo sukurtos dvi programos: garsynų sulyginimo programa ir rezultatų vizualizavimo programa. Garsynų sulyginimo programa sulygino eksperto anotuotą garsyną su automatizuotos anotavimo sistemos anotuotu garsynu. Pagal gaunamus sulyginimo rezultatus buvo galima spręsti apie parinktų parametrų reikšmių gerumą. Gauti sulyginimo rezultatai buvo atvaizduojami rezultatų atvaizdavimo programos pagalba. / In my master degree work I am trying to optimize values of parameters for automatic sound annotation, by using hidden Markov models method. In this research were analyzed 25 different speakers. It was used 60min of speak records for learning and 1 record of 2min speak for testing of all speakers. In this research were used four types of experiments which were named: combination of HMM models, HMM correction number, insertion of all Gaussian mixtures at once, insertion of Gaussian mixtures by increasing mixtures one by one. There was created two programs for facilitating experiment execution: corpus comparison program, result visualization program. Corpus comparison program compares two corpuses expert annotated corpus and automatic annotation system’s annotated corpus. From these results we find out how good are the parameter values. The comparison results can be visualized with the visualization program.
9

Potential based prediction markets : a machine learning perspective

Hu, Jinli January 2017 (has links)
A prediction market is a special type of market which offers trades for securities associated with future states that are observable at a certain time in the future. Recently, prediction markets have shown the promise of being an abstract framework for designing distributed, scalable and self-incentivized machine learning systems which could then apply to large scale problems. However, existing designs of prediction markets are far from achieving such machine learning goal, due to (1) the limited belief modelling power and also (2) an inadequate understanding of the market dynamics. This work is thus motivated by improving and extending current prediction market design in both aspects. This research is focused on potential based prediction markets, that is, prediction markets that are administered by potential (or cost function) based market makers (PMM). To improve the market’s modelling power, we first propose the partially-observable potential based market maker (PoPMM), which generalizes the standard PMM such that it allows securities to be defined and evaluated on future states that are only partially-observable, while also maintaining the key properties of the standard PMM. Next, we complete and extend the theory of generalized exponential families (GEFs), and use GEFs to free the belief models encoded in the PMM/PoPMM from always being in exponential families. To have a better understanding of the market dynamics and its link to model learning, we discuss the market equilibrium and convergence in two main settings: convergence driven by traders, and convergence driven by the market maker. In the former case, we show that a market-wise objective will emerge from the traders’ personal objectives and will be optimized through traders’ selfish behaviours in trading. We then draw intimate links between the convergence result to popular algorithms in convex optimization and machine learning. In the latter case, we augment the PMM with an extra belief model and a bid-ask spread, and model the market dynamics as an optimal control problem. This convergence result requires no specific models on traders, and is suitable for understanding the markets involving less controllable traders.
10

Comparação entre métodos de imputação de dados em diferentes intensidades amostrais na série homogênea de precipitação pluvial da ESALQ / Comparison between data imputation methods at different sample intensities in the ESALQ homogeneous rainfall series

Gasparetto, Suelen Cristina 07 June 2019 (has links)
Problemas frequentes nas análises estatísticas de informações meteorológicas são a ocorrência de dados faltantes e ausência de conhecimento acerca da homogeneidade das informações contidas no banco de dados. O objetivo deste trabalho foi testar e classificar a homogeneidade da série de precipitação pluvial da estação climatológica convencional da ESALQ, no período de 1917 a 1997, e comparar três métodos de imputação de dados, em diferentes intensidades amostrais (5%, 10% e 15%) de informações faltantes, geradas de forma aleatória. Foram utilizados três testes de homogeneidade da série: Pettitt, Buishand e normal padrão. Para o \"preenchimento\" das informações faltantes, foram comparados três métodos de imputação múltipla: PMM (Predictive Mean Matching), random forest e regressão linear via método bootstrap, em cada intensidade amostral de informações faltantes. Os métodos foram utilizados por meio do pacote MICE (Multivariate Imputation by Chained Equations) do R. A comparação entre cada procedimento de imputação foi feita por meio da raiz do erro quadrático médio, índice de exatidão de Willmott e o índice de desempenho. A série de chuva foi entendida como de classe 1, ou seja, \"útil\" - Nenhum sinal claro de falta de homogeneidade foi aparente e, o método que resultou em menores valores da raiz quadrada dos erros e maiores índices foi o PMM, em especial na intensidade de 10% de informações faltantes. O índice de desempenho para os três métodos de imputação de dados em todas as intensidades de observações faltantes foi considerado \"Péssimo\" / Frequent problems in the statistical analyzes of meteorological information are the occurrence of missing data and missing of knowledge about the homogeneity of the information contained in the data base. The objective of this work was to test and classify the homogeneity of the rainfall series of the conventional climatological station of the ESALQ from 1917 to 1997 and to compare three methods of data imputation in different sample intensities (5%, 10% and 15%), of missing data, generated in a random way. Three homogeneity tests were used: Pettitt, Buishand and standard normal. For the \"filling\" of missing information, three methods of multiple imputation were compared: PMM (Predictive Mean Matching), random forest and linear regression via bootstrap method, in each sampling intensity of missing information. The methods were used by means of the MICE (Multivariate Imputation by Chained Equations) package of R. The comparison of each imputation procedure was done by root mean square error, Willmott\'s accuracy index and performance index. The rainfall series was understood to be class 1 \"useful\" - No clear sign of lack of homogeneity was apparent and the method that resulted in smaller values of the square root of the errors and higher indexes was the PMM, in particular the intensity of 10% of missing information. The performance index for the three methods of imputation the data at all missing observation intensities was considered \"Terrible\"

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