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- Biblioteca Digitais de Teses e Dissertações da USP
- Universidade do Minho
- Faculdade de Odontologia de Piracicaba - UNICAMP
- Mary Ann Liebert, Inc.
- Banco Mundial
- Lippincott Williams & Wilkins
- Blackwell Publishing
- Universidade Rice
- Springer; Heidelberg
- Instituto Politécnico do Porto
- Instituto Internacional de Ecologia
- Rochester Instituto de Tecnologia
- FUPEF DO PARANÁ
- Universidade Federal Fluminense - LATEC
- Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
- UNICAMP/FOP
- Mais Publicadores...
Representação computacional de Sistemas a Eventos Discretos considerando a heterogeneidade e a integração dos modelos. ; Computational representation of Discrete Event Dynamic Systems considering the heterogeneity and the integration of models.
Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado
Formato: application/pdf
Publicado em 19/10/2005
PT
Relevância na Pesquisa
35.93%
#computational tools#Discrete Event Dynamic Systems#ferramentas computacionais#heterogeneous models#integração de modelos#integration of models#modelos heterogêneos#Sistemas a Eventos Discretos
Para estudar os chamados Sistemas a Eventos Discretos (SEDs), existe uma variedade de tipos de modelos, mas, entretanto, estes acabam tratando de aspectos sistêmicos específicos, da mesma forma que suas análises. Para ter uma visão mais completa de tais sistemas, é importante lidar com esses tipos heterogêneos de modelos e com as técnicas desenvolvidas para sua integração. Este trabalho foca na questão da representação computacional desses modelos e de como adequá-la à heterogeneidade e à integração desses modelos. No que diz respeito à heterogeneidade, é proposta uma descrição matemática das ferramentas computacionais de modelagem e análise de SEDs, com a qual se pode visualizar as interações entre a heterogeneidade dos modelos, o poder de expressão e de montagem de representações de modelos e os processamentos de análise. Baseado nesta descrição e considerando-se os diversos custos envolvidos, diversas características são analisadas, de modo que, ao final, determina-se quais aquelas que são favoráveis para o caso de heterogeneidade e integração de modelos. Porém, existe ainda a heterogeneidade inerente aos modelos que não pode ser eliminada e isso constitui um obstáculo no caso de ter de lidar com modelos heterogêneos...
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Formulação de modelos de processo para o planejamento da produção em refinarias de petróleo.; Development of process models for the production planning in petroleum refineries.
Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado
Formato: application/pdf
Publicado em 03/12/2009
PT
Relevância na Pesquisa
35.93%
#Development of process models#Formulação de modelos de processo#Nonlinear programming#Otimização não linear#Petroleum refineries#Planejamento da produção#Production planning#Refinarias de petróleo
Durante muitos anos tem-se usado a técnica de programação linear (Linear programming- LP) para abordar o problema do planejamento da produção em refinarias de petróleo. Esta técnica é baseada na linearização do comportamento não linear dos processos num conjunto particular de condições operacionais. Contudo, modelos lineares não são uma boa representação da operação dos processos de refino, pois estes envolvem diferentes operações físicas (separação de fases, mistura de correntes intermediárias, etc.) e químicas (reações de craqueamento, reações de hidrotratamento, etc.) caracterizadas pelo seu comportamento não linear. Como conseqüência, os resultados (plano de operação) de modelos de planejamento da produção baseados na técnica de programação linear são de difícil implementação na operação. Por outro lado, recentes avanços na capacidade de cálculo dos computadores, assim como nas ferramentas matemáticas (algoritmos de otimização) utilizadas para solucionar os modelos de planejamento da produção, permitem a implementação de modelos não lineares de processos em modelos de planejamento da produção. Este trabalho é focado na formulação de modelos de processos adequados (boa aproximação da operação e baixo custo computacional) para o planejamento da produção em refinarias de petróleo. Inicialmente...
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Previsão do volume diário de atendimentos no serviço de pronto socorro de um hospital geral: comparação de diferentes métodos; Forecasting daily emergency department visits using calendar variables and ambient temperature readings: comparison of different models applied to a setting in Sao Paulo - Brazil
Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado
Formato: application/pdf
Publicado em 11/09/2013
PT
Relevância na Pesquisa
35.97%
#Emergency medical
services/organization & administration#Emergency medical services/statistics &
numerical data#Epidemiologia dos serviços de saúde#Estudos de séries temporais#Forecasting/methods#Health service epidemiology#Health services needs and demand/trends#Linear models#Modelos estatísticos#Modelos lineares#Models statistical
OBJETIVOS: O estudo explorou diferentes métodos de séries temporais visando desenvolver um modelo para a previsão do volume diário de pacientes no Pronto Socorro do Instituto Central do Hospital das Clínicas da Faculdade de Medicina da USP. MÉTODOS: Foram explorados seis diferentes modelos para previsão do número diário de pacientes no pronto socorro de acordo com algumas variáveis relacionadas ao calendário e à temperatura média diária. Para a construção dos modelos, utilizou-se a contagem diária de pacientes atendidos no pronto socorro entre 1° de janeiro de 2008 a 31 de dezembro de 2010. Os primeiros 33 meses do banco de dados foram utilizados para o desenvolvimento e ajuste dos modelos, e os últimos três meses foram utilizados para comparação dos resultados obtidos em termos da acurácia de previsão. A acurácia foi medida a partir do erro médio percentual absoluto. Os modelos foram desenvolvidos utilizando-se três diferentes métodos: modelos lineares generalizados, equações de estimação generalizadas e modelos sazonais autorregressivos integrados de média móvel (SARIMA). Para cada método, foram testados modelos que incluíram termos para controlar o efeito da temperatura média diária e modelos que não incluíram esse controle. RESULTADOS: Foram atendidos...
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Use of sectorial essential models in organizational interventions aiming at the implementation of quality assurance processes
Fonte: Universidade do Minho
Publicador: Universidade do Minho
Tipo: Artigo de Revista Científica
Publicado em //2014
POR
Relevância na Pesquisa
35.93%
#Organizational development#Information systems#Models#Quality assurance system#Sectorial essential models
In view of the growing supply of models in various domains and in different formats, and the potential
benefits to organizations using them, this article proposes to (1) present the theoretical background to the
organizational developments, (2) to propose a framework for defining organizational models of quality in
HEIs, and (3) situate and discuss issues associated with the use of methodological approaches that
employ, “as is” and “to be” models, but also “ought to be” models and the benefits of the use of sectorial
essential models, in organizational interventions. Organizational intervention is a generic designation for
any activity involving organizational change, in order to achieve benefits for the organization. The interventions that adopt information technologies, or at least, the introduction of significant changes in
activities with a strong emphasis in information processing, are especially relevant. This definition
comprises organizational interventions, which aim at implementing quality assurance processes.
This work in progress emphasises the following representations: business processes; management
indicators for a business’ sector; business conceptual model (ontology). These models correspond to good organizational practices of a specific sector...
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Reliability of measurements on virtual models obtained from scanning of impressions and conventional plaster models
Fonte: Faculdade de Odontologia de Piracicaba - UNICAMP
Publicador: Faculdade de Odontologia de Piracicaba - UNICAMP
Tipo: Artigo de Revista Científica
Formato: text/html
Publicado em 01/12/2014
EN
Relevância na Pesquisa
35.93%
Aim: To evaluate the reliability of linear measurements in virtual models by comparing measurements performed on virtual models obtained from alginate impression scans, plaster model and measurements performed on conventional plaster model. Methods: The sample comprised 26 randomly selected patients to have impressions of their upper and lower jaws taken using alginate and their bite registration using a wax bite. The virtual models were obtained by scanning the alginate impression and the plaster model in a laser surface scanner (R700; 3Shape, Copenhagen, Denmark), and the measurements were performed using the Ortho Analyser (3Shape) proprietary software. The linear measurements of the size of the teeth mesial to distal, arch perimeter, intercanine distance and intermolar distance in the upper and lower arches were performed on plaster models, digital impressions and digital models, by three observers and repeated after 15 days on 8 models for intra-observer evaluations. Data were tabulated and analyzed statistically. Intra-class correlation to check the agreement of intra and inter-observers and ANOVA test were used to analyze the differences between measurements of digital models from impression and digital models from plaster. Results: The results showed a statistically significant difference (pd"0.05) for the posterior teeth...
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Translational Models for Musculoskeletal Tissue Engineering and Regenerative Medicine
Fonte: Mary Ann Liebert, Inc.
Publicador: Mary Ann Liebert, Inc.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
35.93%
The National Institutes of Health–sponsored workshop “Translational Models for Musculoskeletal Tissue Engineering and Regenerative Medicine” was held to describe the utility of various translational models for engineered tissues and regenerative medicine therapies targeting intervertebral disc, cartilage, meniscus, ligament, tendon, muscle, and bone. Participants included leaders in the various topics, as well as National Institutes of Health and Food and Drug Administration. The Food and Drug Administration representatives provided perspectives and needs for studies supported by animal models. Researchers described animal models for specific tissues and addressed the following questions: (1) What are the unmet musculoskeletal clinical needs that may be addressed by tissue engineering and regenerative medicine? (2) Are there appropriate models available? (3) Are there needs to develop standardized animal models? (4) What are the translational pathways that lead to clinical trials and therapeutic development? The workshop provided an effective and succinct summary of the status of various animal models in musculoskeletal regenerative medicine. Although many models are available and serve well to answer a variety of questions, the general consensus was that there is a substantial need for improved and standardized animal models for tissue engineering and regenerative medicine of the musculoskeletal system...
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Energy Demand Models for Policy Formulation : A Comparative Study of Energy Demand Models
Fonte: Banco Mundial
Publicador: Banco Mundial
Relevância na Pesquisa
35.93%
#AFFORDABLE ENERGY#AGGREGATE DEMAND#AGGREGATE ENERGY DEMAND#AGGREGATE LEVEL#AGRICULTURE#ALLOCATION MODEL#ALTERNATIVE USES#ANNUAL ENERGY OUTLOOK#APPLIANCE STOCKS#APPROACH#AVAILABILITY
This paper critically reviews existing
energy demand forecasting methodologies highlighting the
methodological diversities and developments over the past
four decades in order to investigate whether the existing
energy demand models are appropriate for capturing the
specific features of developing countries. The study finds
that two types of approaches, econometric and end-use
accounting, are used in the existing energy demand models.
Although energy demand models have greatly evolved since the
early 1970s, key issues such as the poor-rich and
urban-rural divides, traditional energy resources, and
differentiation between commercial and non-commercial energy
commodities are often poorly reflected in these models.
While the end-use energy accounting models with detailed
sector representations produce more realistic projections
compared with the econometric models, they still suffer from
huge data deficiencies especially in developing countries.
Development and maintenance of more detailed energy
databases...
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The performance of compartmental and physiologically based recirculatory pharmacokinetic models for propofol: A comparison using bolus, continuous, and target-controlled infusion data
Fonte: Lippincott Williams & Wilkins
Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Publicado em //2010
EN
Relevância na Pesquisa
35.95%
#Humans#Propofol#Anesthetics, Intravenous#Monitoring, Intraoperative#Infusions, Intravenous#Injections, Intravenous#Models, Statistical#Reproducibility of Results#Tissue Distribution#Computer Simulation#Adolescent
BACKGROUND: With the growing use of pharmacokinetic (PK)-driven drug delivery and/or drug advisory displays, identifying the PK model that best characterizes propofol plasma concentration (Cp) across a variety of dosing conditions would be useful. We tested the accuracy of 3 compartmental models and 1 physiologically based recirculatory PK model for propofol to predict the time course of propofol Cp using concentration-time data originated from studies that used different infusion schemes. METHODS: Three compartmental PK models for propofol, called the “Marsh,” the “Schnider,” and the “Schüttler” models, and 1 physiologically based recirculatory model called the “Upton” model, were used to simulate the time course of propofol Cp. To test the accuracy of the models, we used published measured plasma concentration data that originated from studies of manual (bolus and short infusion) and computer-controlled (target-controlled infusion [TCI] and long infusion) propofol dosing schemes. Measured/predicted (M/P) propofol Cp plots were constructed for each dataset. Bias and inaccuracy of each model were assessed by median prediction error (MDPE) and median absolute prediction error (MDAPE), respectively. RESULTS: The M/P propofol Cp in the 4 PK models revealed bias in all 3 compartmental models during the bolus and short infusion regimens. In the long infusion...
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Using scalar models for precautionary assessments of threatened species
Fonte: Blackwell Publishing
Publicador: Blackwell Publishing
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.94%
#population viability analysis#threatened species#matrix models#extinction risk#count-based PVA#age structure
Scalar population models, commonly referred to as count-based models, are based on time-series
data of population sizes and may be useful for screening-level ecological risk assessments when data for
more complex models are not available. Appropriate use of such models for management purposes, however,
requires understanding inherent biases that may exist in these models. Through a series of simulations, which
compared predictions of risk of decline of scalar and matrix-based models, we examined whether discrepancies
may arise from different dynamics displayed due to age structure and generation time. We also examined
scalar and matrix-based population models of 18 real populations for potential patterns of bias in population
viability estimates. In the simulation study, precautionary bias (i.e., overestimating risks of decline) of scalar
models increased as a function of generation time. Models of real populations showed poor fit between scalar
and matrix-based models, with scalar models predicting significantly higher risks of decline on average. The
strength of this bias was not correlated with generation time, suggesting that additional sources of bias may be
masking this relationship. Scalar models can be useful for screening-level assessments...
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Probabilistic Models for Genetic and Genomic Data with Missing Information
Fonte: Universidade Rice
Publicador: Universidade Rice
ENG
Relevância na Pesquisa
35.93%
Genetic and genomic data often contain unobservable or missing information. Applications of probabilistic models such as mixture models and hidden Markov models (HMMs) have been widely used since the 1960s to make inference on unobserved information using some observed information demonstrating the versatility and importance of these models. Biological applications of mixture models include gene expression data, meta-analysis, disease mapping, epidemiology and pharmacology and applications of HMMs include gene finding, linkage analysis, phylogenetic analysis and identifying regions of identity-by-descent. An important statistical and informatics challenge posed by modern genetics is to understand the functional consequences of genetic variation and its relation to phenotypic variation. In the analysis of whole-exome sequencing data, predicting the impact of missense mutations on protein function is an important factor in identifying and determining the clinical importance of disease susceptibility mutations in the absence of independent data determining impact on disease. In addition to the interpretation, identifying co-inherited regions of related individuals with Mendelian disorders can further narrow the search for disease susceptibility mutations. In this thesis...
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Some algebra and geometry for hierarchical models, applied to diagnostics
Fonte: Wiley
Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //1998
EN
Relevância na Pesquisa
35.95%
#Bayesian methods#Dynamic linear models#Multilevel models#Random effect models#Spatial data#Time varying regression#Variance component
Recent advances in computing make it practical to use complex hierarchical models. However, the complexity makes it difficult to see how features of the data determine the fitted model. This paper describes an approach to diagnostics for hierarchical models, specifically linear hierarchical models with additive normal or t-errors. The key is to express hierarchical models in the form of ordinary linear models by adding artificial `cases' to the data set corresponding to the higher levels of the hierarchy. The error term of this linear model is not homoscedastic, but its covariance structure is much simpler than that usually used in variance component or random effects models. The re-expression has several advantages. First, it is extremely general, covering dynamic linear models, random effect and mixed effect models, and pairwise difference models, among others. Second, it makes more explicit the geometry of hierarchical models, by analogy with the geometry of linear models. Third, the analogy with linear models provides a rich source of ideas for diagnostics for all the parts of hierarchical models. This paper gives diagnostics to examine candidate added variables, transformations, collinearity, case influence and residuals.; James S. Hodges
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Simulation of rainfall anomalies leading to the 2005 drought in Amazonia using the CLARIS LPB regional climate models
Fonte: Springer; Heidelberg
Publicador: Springer; Heidelberg
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.93%
The meteorological characteristics of the
drought of 2005 in Amazonia, one of the most severe in the
last 100 years were assessed using a suite of seven regional
models obtained from the CLARIS LPB project. The
models were forced with the ERA-Interim reanalyses as
boundary conditions. We used a combination of rainfall
and temperature observations and the low-level circulation
and evaporation fields from the reanalyses to determine the
climatic and meteorological characteristics of this particular
drought. The models reproduce in some degree the
observed annual cycle of precipitation and the geographical
distribution of negative rainfall anomalies during the
summer months of 2005. With respect to the evolution of
rainfall during 2004–2006, some of the models were able to
simulate the negative rainfall departures during early
summer of 2005 (December 2004 to February 2005). The
interannual variability of rainfall anomalies for both austral
summer and fall over northern and southern Amazonia
show a large spread among models, with some of them
capable of reproducing the 2005 observed negative rainfall
departures (four out of seven models in southern Amazonia
during DJF). In comparison, all models simulated the
observed southern Amazonia negative rainfall and positive
air temperature anomalies during the El Nino-related
drought in 1998. The spatial structure of the simulated rainfall and temperature anomalies in DJF and MAM 2005
shows biases that are different among models. While some
models simulated the observed negative rainfall anomalies
over parts of western and southern Amazonia during DJF...
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Vibração induzida por vórtices: análise crítica de modelos fenomenológicos. ; Vortex induced vibration: critical analysis of phenomenological models.
Fonte: Biblioteca Digitais de Teses e Dissertações da USP
Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado
Formato: application/pdf
Publicado em 05/12/2005
PT
Relevância na Pesquisa
35.93%
#dynamical systems#modelos fenomenológicos#numerical simulation#petroleum plataforms#phenomenological models#plataformas de petróleo#simulação numérica#sistemas dinâmicos#vibração induzida por vórtices#vortex induced vibration
O presente trabalho analisa criticamente um conjunto de resultados sobre a fundamentação, simulação e aplicabilidade de alguns modelos fenomenológicos para Vibração Induzida por Vórtices, ou VIV. São estudados os modelos de Hartlen&Currie, 1970, de Iwan&Blevins, 1975, e de Facchinetti&de Langre&Biolley, 2004. O estudo foi desenvolvido com os propósitos: fundamentar, com base em resultados teóricos e experimentais existente na literatura, a representatividade do fenômeno de VIV através desta classe de modelos; obter resultados da simulação numérica destes modelos para posterior confrontação com dados experimentais disponíveis na literatura; discutir a possibilidade de aplicação destes modelos na prática da engenharia. A fundamentação dos modelos fenomenológicos é obtida do trabalho de Aranha, 2004, que conclui pela possibilidade teórica de representar os fenômeno de VIV através de um conjunto de equações diferenciais simplificadas. Este fato traz embasamento aos modelos fenomenológicos, que partem deste princípio de simplificação e resultam em equações similares àquelas desenvolvidas por Aranha. Para desenvolver a simulação numérica dos três modelos foi idealizado um programa de computação científica capaz de resolver numericamente as equações diferenciais ordinárias dos modelos...
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Estudo e integração de business models e a sua aplicação em smart-ups e projetos portugueses
Fonte: Instituto Politécnico do Porto
Publicador: Instituto Politécnico do Porto
Tipo: Dissertação de Mestrado
Publicado em //2015
POR
Relevância na Pesquisa
35.94%
Dissertação apresentada ao Instituto Superior de Contabilidade e
Administração do Porto para obtenção do Grau de Mestre em Gestão das
Organizações, Ramo Gestão de Empresas
Orientador: Professor Doutor Eduardo Manuel Lopes de Sá e Silva
Co-orientador: Mestre Maria de Fátima Mendes Monteiro; Os últimos anos trouxeram muitas mudanças no cenário económico. Condições como avanços
tecnológicos, a globalização e a crise que estamos a viver no nosso país, parecem ter sido fatores
que ao contrário do que seria de esperar, influenciaram o desenvolvimento do empreendedorismo.
Com vista a melhorar o seu desempenho no mercado, as start-ups acabam por adotar modelos
para sintetizar toda a informação e tirar conclusões. Estes modelos são designados como
business models. Nesta dissertação, proponho-me a desenvolver um modelo mais completo com
base nos business models já existentes e testá-lo numa startup portuguesa. No primeiro capitulo
da dissertação serão estudados cinco business models, sendo eles, Outcome-Driven Innovation,
Blue Ocean Strategy, Customer Development, Customer Brand-Based Equity e Discovery Driven
Planning.
Seguidamente, no segundo capitulo, pretende-se integrar todos os business models num modelo
bastante mais simples...
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Comments about some species abundance patterns: classic, neutral, and niche partitioning models
Fonte: Instituto Internacional de Ecologia
Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica
Formato: text/html
Publicado em 01/11/2008
EN
Relevância na Pesquisa
35.93%
#species abundance patterns#neutral models#niche partitioning models#log-normal curve#Power fraction model
The literature on species abundance models is extensive and a great deal of new and important contributions have been published in the last three decades. Broadly speaking, one can recognize five families of species abundance models: i) purely statistical or classic models (Broken-stick, Log-normal, Logarithmic and Geometric series); ii) branching process (Zipf-Mandelbrot and Fractal branching models); iii) population dynamics (Neutral models included); iv) spatial distribution of individuals (Multifractal and HEAP models) and v) niche partitioning (Sugihara's breakage and Tokeshi models). Among these the neutral, the classic and the niche partitioning models have been the most applied to natural communities, the former having been more extensively discussed than the others in the last years. The objective of this paper is to comment some aspects of the classic, neutral and niche partitioning models in a way that the proposed distributions may contribute to the analysis of the empirical patterns of species abundance. In spite of the variety of models, the distributions in general vary between the log-normal and the logarithmic series. From these models the Power-Fraction, together with independent niche dimensions measures, are amenable to experimental tests and may offer answers on which resources are important in the structuring of biological communities.
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Investigation and development of advanced models of thermoelectric generators for power generation applications
Fonte: Rochester Instituto de Tecnologia
Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
35.93%
#Asymptotic#Finite element#Heat transfer#Modeling#Power generation#Thermoelectric#TK2950 .S36 2009#Thermoelectric generators--Mathematical models
With developing interest in power generation applications of thermoelectrics and the growing influence of advanced materials on thermoelectric device fabrication, there is an increased demand for better understanding of module-level behavior. Likewise, novel module geometries are being explored for higher performance and require sophisticated modeling methods.
In addition to new geometrical design, transport phenomena, such as Thomson heating and contact resistances, aggravate the complexity of modeling thermoelectric modules (TEMs) and thus limit design capability. Typically, these effects are either approximated (or in some cases neglected entirely) with little exploration in to the validity of the underlying assumptions associated with the approximation. As such, standard models are often predicated on assumptions that cannot be made beyond very limited operating regimes. Consequently, most TEM analysis generally utilizes simplistic methods of modeling on a module-level scale, which introduce inaccuracies that must be redressed.
Particularly with larger temperature gradients, typically negligible effects could begin to impact overall system performance. Material property temperature-dependency, combined with leakage effects...
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Mixed volumetric models in clones of Eucalyptus in the gypsum pole of Araripe, Pernambuco; MODELOS VOLUMÉTRICOS MISTOS EM CLONES DE EUCALYPTUS NO POLO GESSEIRO DO ARARIPE, PERNAMBUCO
Fonte: FUPEF DO PARANÁ
Publicador: FUPEF DO PARANÁ
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares
Formato: application/pdf
Publicado em 26/02/2015
POR
Relevância na Pesquisa
35.93%
##Forest inventory#volumetric estimation#comparing models.#Ciência Florestal#Inventário florestal#estimação volumétrica#comparação entre modelos.
AbstractThe present research aimed to estimate the volume of Eucalyptus clones using mixed models. The database was derived from an experiment of Eucalyptus clones, located in the Chapada do Araripe, semiarid of the Pernambuco State. 89 trees were cubed by the method Smalian at the age of seven and a half years. The model of Schumacher and Hall was used as a control for comparison with the nonlinear mixed models. The adjustments of the mixed models were performed by adopting six distinct structures for the matrix of variances and covariances. The selection the best equation was done using the Akaike information criterion (AIC) Test Likelihood Ratio (TRMV), Mean Absolute Percentage Error (EPAM) and Vuong test. According to the criteria adopted, mixed models obtain better adjustments when compared with the classical model of Schumacher and Hall, resulting in a decrease in mean absolute percentage error of 4.6% to 3.2%. Based on these results, the nonlinear mixed models appear quite effective for modeling the volume of Eucalyptus and tend to contribute to the reduction of inventory costs with greater accuracy.; O presente estudo teve como objetivo estimar o volume de clones de Eucalyptus utilizando modelos mistos. A base de dados foi proveniente de um povoamento de clones de Eucalyptus localizado na Chapada do Araripe...
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The applicability of linear regression models in working environments’ thermal evaluation; THE APPLICABILITY OF LINEAR REGRESSION MODELS IN WORKING ENVIRONMENTS’ THERMAL EVALUATION; THE APPLICABILITY OF LINEAR REGRESSION MODELS IN WORKING ENVIRONMENTS’ THERMAL EVALUATION
Fonte: Universidade Federal Fluminense - LATEC
Publicador: Universidade Federal Fluminense - LATEC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ;
Formato: application/pdf
Publicado em 25/05/2006
POR
Relevância na Pesquisa
35.95%
#Engenharia#Engenharia de Produção#Matemática#regression models#thermal evaluation#working environments##regression models#thermal evaluation#working environments#
The simultaneous analysis of thermal variables with normal distribution with the aim of checking if there is any significative correlation among them or if there is the possibility of making predictions of the values of some of them based on others’ values is considered a problem of great importance in statistics studies. The aim of this paper is to study the applicability of linear regression models in working environments’ thermal comfort studies, thus contributing for the comprehension of the possible environmental cooling, heating or winding needs. It starts with a bibliographical research, followed by a field research, data collection and and software statistical-mathematical data treatment. It was then performed data analysis and the construction of the regression linear models using the t and F tests for determining the consistency of the models and their parameters, as well as the building of conclusions based on the information obtained and on the significance of the mathematical models built.; The simultaneous analysis of thermal variables with normal distribution with the aim of checking if there is any significative correlation among them or if there is the possibility of making predictions of the values of some of them based on others’ values is considered a problem of great importance in statistics studies. The aim of this paper is to study the applicability of linear regression models in working environments’ thermal comfort studies...
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Composição corporal, gasto energético e ingestão alimentar em modelos brasileiras; Body composition, energy expenditure and food intake in brazilian fashion models
Fonte: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
Publicador: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; "Avaliado por Pares",; ; Avaliado por Pares; Correlacional
Formato: application/pdf; application/pdf
Publicado em 09/12/2008
POR; ENG
Relevância na Pesquisa
35.94%
#Fisiologia. Medicina do Esporte.#Adolescente#Modelos#Composição corporal#Ingestão alimentar#Adolescent#Fashion models#Body composition#Body fat#Food intake.#
http://dx.doi.org/10.5007/1980-0037.2009v11n1p1 O objetivo desse estudo foi comparar a composição corporal, taxa de metabolismo em repouso e ingestão alimentar entre adolescentes modelos e não modelos. Participaram do estudo 33 modelos e 33 não modelos, de 15 a 18 anos, pareadas por idade e IMC. A avaliação da composição corporal foi realizada por meio da técnica de pletismografia. A taxa de metabolismo em repouso (TMR) foi obtida pelo método da calorimetria indireta e a avaliação da ingestão alimentar foi realizada por meio de um registro alimentar de 3 dias alternados. Não houve diferença estatisticamente significante em relação aos valores médios de percentual de gordura corporal entre os grupos estudados (p>0,05). Entretanto, ao classificar as adolescentes quanto ao percentual de gordura corporal, observou-se que nenhuma modelo apresentou percentual de gordura corporal menor do que 15%, enquanto 15,2% das adolescentes não modelos apresentaram baixo percentual de gordura corporal (p<0,05). Os valores de TMR (kcal/d) foram semelhantes entre modelos (1367,22) e não modelos (1309,43) (p>0,05). Em relação à ingestão de energia, observou-se que a média de ingestão energética foi 1480,93kcal ± 582...
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Reliability of measurements on virtual models obtained from scanning of impressions and conventional plaster models
Fonte: UNICAMP/FOP
Publicador: UNICAMP/FOP
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ;
Publicado em 30/12/2010
POR
Relevância na Pesquisa
35.93%
Aim: To evaluate the reliability of linear measurements in virtual models by comparing measurements performed on virtual models obtained from alginate impression scans, plaster model and measurements performed on conventional plaster model. Methods: The sample comprised 26 randomly selected patients to have impressions of their upper and lower jaws taken using alginate and their bite registration using a wax bite. The virtual models were obtained by scanning the alginate impression and the plaster model in a laser surface scanner (R700; 3Shape, Copenhagen, Denmark), and the measurements were performed using the Ortho Analyser (3Shape) proprietary software. The linear measurements of the size of the teeth mesial to distal, arch perimeter, intercanine distance and intermolar distance in the upper and lower arches were performed on plaster models, digital impressions and digital models, by three observers and repeated after 15 days on 8 models for intra-observer evaluations. Data were tabulated and analyzed statistically. Intra-class correlation to check the agreement of intra and inter-observers and ANOVA test were used to analyze the differences between measurements of digital models from impression and digital models from plaster. Results: The results showed a statistically significant difference (pd”0.05) for the posterior teeth...
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