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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.
51

Approximation and higher order Statistics for the Kappa-Mu phase fading model = Aproximação e estatísticas de ordem superior para a fase do modelo de desvanecimento Kappa-Mu / Aproximação e estatísticas de ordem superior para a fase do modelo de desvanecimento Kappa-Mu

Porto, Iury Bertollo Gomes, 1986- 08 October 2012 (has links)
Orientador: Michel Daoud Yacoub / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-21T10:53:47Z (GMT). No. of bitstreams: 1 Porto_IuryBertolloGomes_M.pdf: 2176563 bytes, checksum: 657761eeebab35f7888762aa91c017cd (MD5) Previous issue date: 2012 / Resumo: Esta tese apresenta alguns resultados importantes das estatísticas de fase do modelo de desvanecimento kappa-mu. Em particular, a taxa de cruzamento de fase é obtida de maneira exata. Adicionalmente, para evitar a complexidade das formulações exatas, foram propostas soluções aproximadas para as seguintes estatísticas: taxa de cruzamento de fase e função densidade de probabilidade de fase. Além disso, uma metodologia de simulação foi desenvolvida para validar as formulações. Finalmente, dados de campo obtidos através de medidas conduzidas por outros pesquisadores foram usados para adequar às estatísticas de fase, tanto para o modelo kappa-mu quanto para Nakagami-m generalizado / Abstract: This thesis concerns some important results regarding the phase statistics of the kappa-mu fading model. In particular, the phase crossing rate is obtained in an exact manner. In addition, in order to circumvent the intricacy of the exact formulations, approximate solutions for the following statistics are proposed: phase crossing rate and probability density function of the phase. Furthermore, a simulation methodology is developed so as to validate the formulations. Finally, field data obtained by measurements conducted elsewhere are used to fit the phase statistics for both kappa-mu and generalized Nakagami-m models / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
52

Distribuição bivariável kappa-mu / A Bivariate kappa-mu distribution

Gomez Villavicencio, Mirko Alberto, 1982- 26 August 2018 (has links)
Orientador: Michel Daoud Yacoub / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-26T17:46:44Z (GMT). No. of bitstreams: 1 GomezVillavicencio_MirkoAlberto_M.pdf: 2402841 bytes, checksum: 68bbd5454c4ebb5de373b3e095e468b2 (MD5) Previous issue date: 2014 / Resumo: Nesta dissertação, uma distribuição bivariável kappa -mu é apresentada. Exatas expressões para a função densidade de probabilidade conjunta, função distribuição cumulativa conjunta, e os momentos arbitrários conjuntos são encontradas. As estatísticas conjuntas são dadas em termos de seus respectivos parâmetros (kappa1 , mu1 ) e (kappa_2$, mu_2), com mu1 =mu2 = mu> 0 e arbitrários kappa1> 0 e kappa2> 0. Como exemplo de aplicação, a probabilidade de outage para o caso de dois ramos por combinação por seleção pura, combinação por razão máxima e combinação por ganho igual são apresentadas / Abstract: In this thesis, a bivariate kappa-mu model is presented. Exact expressions for the joint probability density function, joint cumulative distribution function, and joint arbitrary moments are found. The joint statistics are given in terms of their respective parameters (kappa1, mu1) and (kappa2, mu2), with mu1=mu2=mu >0 and arbitrary kappa1>0 and kappa2>0. As an application example, the outage probability of a dual-branch pure selection combining, maximo ratio combining and equal gain combining scheme are presented / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
53

Ajuste de curvas por polinômios com foco no currículo do ensino médio / Curve fitting polynomials focusing on high school curriculum

Santos, Alessandro Silva, 1973- 27 August 2018 (has links)
Orientador: Lúcio Tunes dos Santos / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-27T11:38:45Z (GMT). No. of bitstreams: 1 Santos_AlessandroSilva_M.pdf: 6474871 bytes, checksum: 351d93b093e44b399a99cd42075cb4b5 (MD5) Previous issue date: 2015 / Resumo: ste trabalho surge a partir de uma proposta de desenvolvimento do ajuste de curvas com uma abordagem que busca enriquecer o estudo de funções presente no currículo do ensino fundamental e médio. É apresentada ao aluno, desde o aspecto histórico do ajuste, passando pela interpolação de curvas, com foco na interpolação polinomial e o método dos quadrados mínimos, no qual são apresentados, a regressão linear, além de modelos como o ajuste exponencial. É também descrita nesta dissertação uma ferramenta de grande importância no cálculo numérico, o conceito de erro de ajuste, sua definição e forma de estimativa. Na interpolação polinomial, o aluno, ao desenvolver a forma de Lagrange, é estimulado a trabalhar as operações, forma fatorada e interpretação das vantagens do método, como o número e grau de dificuldade de operações realizadas por esse. Interpolação inversa e interpolação de curvas complementam o referido capítulo, em que busca, sempre que possível, utilizar situações problema . O método dos quadrados mínimos estimula o estudante a escolha da função de ajuste e determinação dessa a partir do conceito de minimização do erro. Polinômios de grau um,a regressão linear, e dois são trabalhados devido a sua importância no currículo do ensino médio. Explorando também conceitos como logaritmos e exponenciais, propõe-se o ajuste linear de modelos exponenciais, utilizando situações problema de uma área em evidência no momento, a Biomatemática, modelar dinâmicas de crescimento populacional. Dessa forma o aluno tem contato com formas de previsão que são úteis em importantes áreas como: a saúde pública, a modelagem de epidemias e desenvolvimento de patógenos; planejamento de políticas públicas com a modelagem do crescimento e distribuição da população; comportamento da economia como no caso de previsões de juros futuros. Para que este trabalho possa servir de auxílio aos professores de forma prática e interessante, o capítulo final traz sugestão de problemas na forma de planilha, facilitando sua reprodução e aplicação em sala de aula / Abstract: This study comes from a development proposal curves adjustment with an approach that seeks to enrich the study of present functions in the primary and secondary curriculum. It is presented to the student, from the historical aspect setting, through interpolation curves, focusing on polynomial interpolation and the method of least squares, which presents the linear regression, and models like the exponential fit. It is also described in this work a very important tool in numerical calculation, the concept of setting error, its definition and method of estimation. In polynomial interpolation, the student, to develop the form of Lagrange, is encouraged to work operations, factored form and interpretation of the advantages of the method, as the number and degree of difficulty of tasks for this. Inverse interpolation and interpolation curves complement the chapter on seeking, whenever possible, use problem situations. The method of least squares stimulates the student the choice of setting function and determine this from the concept of minimizing the error. Polynomials of degree one, linear regression, and two are worked because of its importance in the high school curriculum. Also exploring concepts such as logarithms and exponential, it is proposed that the linear fit of exponential models using problem situations evidence in area at the time, the Biomathematics, modeling dynamics of population growth. Thus the student has contact with forms of provision that are useful in important areas such as public health, the modeling of epidemics and development of pathogens; public policy planning with modeling of growth and distribution of population; behavior of the economy as in the case of future interest rate forecasts. For this work may be an aid to teachers in a practical and interesting, the final chapter brings problems suggestion in the form of sheet, facilitating its reproduction and use in the classroom / Mestrado / Matemática em Rede Nacional - PROFMAT / Mestre em Matemática em Rede Nacional - PROFMAT
54

Interaction of N-Alkylanthracyclines With Lipid Bilayers: Correlations Between Partition Coefficients, Lipid Phase Distributions and Thermotropic Behavior

Constantinides, Panayiotis P., Ghosaini, Lily, Inouchi, Naoyoshi, Kitamura, Shinichi, Seshadri, Ramakrishnan, Israel, Mervyn, Sartorelli, Alan C., Sturtevant, Julian M. 01 January 1989 (has links)
The thermotropic behavior of multilamellar vesicles of dipalmitoylphosphatidylcholine (DPPC), or of DPPC in admixture with cardiolipin or cholesterol, in the presence of various N-alkyl derivatives of both adriamycin-14-valerate has been investigated by high sensitivity differential scanning calorimetry. The analogues, particularly the 14-valerate derivatives, which were most lipophilic as judged by their lipid/buffer, and to a lesser extent by their octanol/buffer, partition coefficients, were the most effective in depressing the tm of the investigated lipids; correlations, however, were not absolute. Other factors, such as the distribution of the drugs between the solid and liquid-crystalline phases of the bilayer, were also important to the observed membrane perturbations. With all anthracyclines, however, no major changes in the transition enthalpy were observed. In the case of vesicles prepared from pure DPPC, curve fitting analysis based on ideal solution theory (J.M. Sturtevant (1984) Proc. Natl. Acad. Sci. USA 81, 1398-1400) applied at relatively low drug concentrations where single peak transitions were produced, adequately described the differential scanning calorimetric results. At high drug concentrations, however, the presence of multipeak transitions were indicative of non-ideality.
55

Modeling of United States Airline Fares -- Using the Official Airline Guide (OAG) and Airline Origin and Destination Survey (DB1B)

Rama-Murthy, Krishna 13 September 2007 (has links)
Prediction of airline fares within the United States including Alaska & Hawaii is required for transportation mode choice modeling in impact analysis of new modes such as NASA's Small Airplane Transportation System (SATS). Developing an aggregate cost model i.e. a 'generic fare model' of the disaggregated airline fares is required to measure the cost of air travel. In this thesis, the ratio of average fare to distance i.e. fare per mile and average fare is used as a measure of this cost model. The thesis initially determines the Fare Class categories to be used for Coach and Business class for the analysis .The thesis then develops a series of 'generic fare models' using round trip distance traveled as an independent variable. The thesis also develops a set of models to estimate average fare for any origin and destination pair in the US. The factors considered by these models are: the round trip distance traveled between the origin (o) and destination (d), the type of fare class chosen by the traveler (first, business class and unrestricted coach class and restricted coach class), the type of airport (large hub, medium hub, small hub, or non hub), whether or not the route is served by a low cost airline and the airline market concentration between the o-d pair. The models suggest that competition at the destination airport is more critical than the competition at origin airport for coach class fares and vice a versa for business class fares. Models suggested in this thesis predict air fares with R-square values of 0.3 to 0.75. / Master of Science
56

A computational framework for analyzing chemical modification and limited proteolysis experimental data used for high confidence protein structure prediction

Anderson, Paul E. 08 December 2006 (has links)
No description available.
57

Systematic Digitized Treatment of Engineering Line-Diagrams

Sui, T.Z., Qi, Hong Sheng, Qi, Q., Wang, L., Sun, J.W. 05 1900 (has links)
Yes / In engineering design, there are many functional relationships which are difficult to express into a simple and exact mathematical formula. Instead they are documented within a form of line graphs (or plot charts or curve diagrams) in engineering handbooks or text books. Because the information in such a form cannot be used directly in the modern computer aided design (CAD) process, it is necessary to find a way to numerically represent the information. In this paper, a data processing system for numerical representation of line graphs in mechanical design is developed, which incorporates the process cycle from the initial data acquisition to the final output of required information. As well as containing the capability for curve fitting through Cubic spline and Neural network techniques, the system also adapts a novel methodology for use in this application: Grey Models. Grey theory have been used in various applications, normally involved with time-series data, and have the characteristic of being able to handle sparse data sets and data forecasting. Two case studies were then utilized to investigate the feasibility of Grey models for curve fitting. Furthermore, comparisons with the other two established techniques show that the accuracy was better than the Cubic spline function method, but slightly less accurate than the Neural network method. These results are highly encouraging and future work to fully investigate the capability of Grey theory, as well as exploiting its sparse data handling capabilities is recommended.
58

Non-linear Curve Fitting

Morad, Farhad January 2019 (has links)
The work done in this thesis is to examine various methods for curve fitting. Linear least squares and non-linear least squares will be described and compared, and the Newton method, Gauss--Newton method and Levenberg--Marquardt method will be applied to example problems. / Syftet med denna uppsats är att beskriva och använda olika metoder för kurvanpassning, det vill säga att passa matematiska funktioner till data. De metoder som undersöks är Newtons metod, Gauss--Newton metoden och Levenberg--Marquardt metoden. Även skillnaden mellan linjär minsta kvadrat anpassning och olinjär minsta kvadrat anpassning. Till sist tillämpas Newton, Gauss Newton och Levenberg--Marquardt metoderna på olika exempel.
59

LUNG DISPOSITION MODEL-BASED ANALYSES OF CLINICAL PHARMACOKINETIC PROFILES FOR INHALED DRUGS

Raut, Anuja 01 January 2017 (has links)
There has been a desire to accurately interpret the inhaled pharmacokinetic (PK) profiles of drugs in humans to aid successful inhaled drug and product developments. However, challenges are layered, as 1) the drug dose delivered to the lung (DTL) from inhalers is a portion of the formulated dose but rarely determined; 2) lung delivery and regional deposition differ, depending on drug, formulation and inhaler; 3) drugs are not only absorbed from the lung but may also be from the gastrointestinal (GI) tract; and 4) in addition to absorption into the systemic circulation, multiple non-absorptive processes also eliminate drugs from the lung, such as mucociliary clearance, metabolism, phagocytosis and tissue binding. Hence, this thesis project aims to develop new lung disposition model-based analyses to derive the meaningful kinetic descriptors for lung disposition from inhaled PK profiles in humans. Two approaches, curve fitting- and moment-based approaches, were developed. Both approaches modeled the kinetics of lung disposition rate-controlled by absorption (ka) and non-absorptive loss (knal), assuming no contribution of GI absorption. An exhaustive literature review found necessary data sets for three drugs, tobramycin, calcitonin and ciprofloxacin. In the curve fitting-based approach, each inhaled PK profile was fitted to the lung disposition model, while the DTL was obtained from corresponding -scintigraphic lung deposition and the kinetic parameters of systemic disposition were fixed by separate intravenous PK profile model analysis. In the moment analysis-based approach, the mean lung residence times (MLRT) and the DTL-based bioavailability (FL) were estimated and used to determine the ka and knal values in the lung disposition model, given FL = MLRTka = ka/(ka+knal). The ka and knal values were successfully derived for all the three drugs delivered by dry powder inhalers (DPIs) and/or nebulizers (NEB) through both approaches. Their “goodness-of-fit” was reasonably satisfactory. The ka values appeared to be primarily described by partition-based diffusion affected by the three hydrophilic drug’s molecular weight. In contrast, the knal values differed, yet appeared to become plausible, with a notion of additional non-absorptive confoundedness due to lung tissue binding (tobramycin) and metabolism (calcitonin), in addition to mucociliary clearance. The ka and knal values derived by the two approaches were comparable in majority of the cases. The success of these PK modeling analyses enabled further attempts to identify most influential attributes by simulation. The systemic PK and lung exposure profiles were predicted by simulation upon ±20 % changes in each of the DTL, ka and knal values to examine changes in the systemic PK metrics (Cmax, AUC and Tmax) and local lung exposure metrics (AUClung and LRT0.5). For all three drugs, the Cmax and AUC changes were identical to changes in the DTL without changing the Tmax. In contrast, impacts of the ka and knal changes differed between drugs, depending on the relative contribution of the rate constant to their sum (ka+knal). It appeared that the major contributor of the sum (ka+knal) was that rate-controlling the kinetics of lung disposition. In conclusion, this thesis project has successfully proposed two new approaches of curve fitting and moment-based analysis by accurately deriving the kinetic descriptors of lung disposition (ka and knal) for three drugs from the inhaled PK profiles in humans. Their applications were extended to predict likely changes in the systemic PK and local lung exposure metrics by simulation. While attempts should continue with more drugs, these approaches are believed to be useful in identifying critical attributes to determine the lung disposition kinetics and thus predicting the lung kinetic behavior and systemic PK profiles of new drug entities in humans.
60

Industrial Applications of Data Mining : Engineering Effort Forecasting based on Mining and Analysis of Patterns in Historical Project Execution Data

January 2013 (has links)
abstract: Data mining is increasing in importance in solving a variety of industry problems. Our initiative involves the estimation of resource requirements by skill set for future projects by mining and analyzing actual resource consumption data from past projects in the semiconductor industry. To achieve this goal we face difficulties like data with relevant consumption information but stored in different format and insufficient data about project attributes to interpret consumption data. Our first goal is to clean the historical data and organize it into meaningful structures for analysis. Once the preprocessing on data is completed, different data mining techniques like clustering is applied to find projects which involve resources of similar skillsets and which involve similar complexities and size. This results in "resource utilization templates" for groups of related projects from a resource consumption perspective. Then project characteristics are identified which generate this diversity in headcounts and skillsets. These characteristics are not currently contained in the data base and are elicited from the managers of historical projects. This represents an opportunity to improve the usefulness of the data collection system for the future. The ultimate goal is to match the product technical features with the resource requirement for projects in the past as a model to forecast resource requirements by skill set for future projects. The forecasting model is developed using linear regression with cross validation of the training data as the past project execution are relatively few in number. Acceptable levels of forecast accuracy are achieved relative to human experts' results and the tool is applied to forecast some future projects' resource demand. / Dissertation/Thesis / M.S. Computer Science 2013

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