... Title: An Efficient and Accurate Method of Estimating Substrate ... This thesis presents a Z-parameter based model to predict the substrate ...

... Accession Number : ADA411757. Title : The Multi-Average Method to Accurately Estimate TEOAE Parameters. Corporate ...

... compounds exhibit hysteresis and constitutive nonlinearities which ... any other provision of law, no person ... yielding the highly accurate fit observed in ...

A simple and sufficiently accurate method is proposed for estimating the parameters of shockwave loading of porous materials under conditions of complete compaction of the material to the density of a monolith.

The estimation of the number of channels in a patch was assumed to be equivalent to the estimation of the binomial parameter n. Seven estimators were evaluated, using data sets simulated for a range of parameters appropriate for single channel recording experiments. No single ...

Through a large-scale simulation study, this article compares item parameter estimates obtained by the marginal maximum likelihood estimation (MMLE) and marginal Bayes modal estimation (MBME) procedures in the 3-parameter logistic model. The impact of different prior specifications on the MBME ...

It is maintained that, at the time of seed bed preparation for the production of durum wheat, Tunisian farmers form subjective estimates of the parameters of the underlying production function. If their estimates are not accurate, resources are not optima...

The generalized gamma distribution has three parameters, the origin, the scale, and the shape. As a model, it serves to approximate univariate distributions in many disciplines. To be an acceptably accurate model, the model parameters estimates should con...

Modelling of the weak lensing of the CMB will be crucial to obtain correct cosmological parameter constraints from forthcoming precision CMB anisotropy observations. The lensing affects the power spectrum as well as inducing non-Gaussianities. We discuss the simulation of full-sky CMB maps in the weak lensing approximation and describe a fast numerical code. The series ...

data as well as estimation of geophysical parameters from SA R data have received a great ... cr , and precision of the estimated forest biomass. 2. METHOI1 ...

and tomotherapy require tight treatment margins. Such tight margins can be achieved through highly accurate

... and S&T - Allows users to query ... service publications, Administrative Instructions, Directive-Type ... these parameters and obtain accurate estimates by ...

... truss. Results indicate stable and accurate state estimation when the bank is initially centered on the true parameter. Stable ...

Describes item response and information functions for the Zinnes and Griggs paired comparison item response theory (IRT) model (1974) and presents procedures for estimating stimulus and person parameters. Monte Carlo simulations show that at least 400 ratings are required to obtain reasonably accurate estimates of ...

Downhole log measurements such as acoustic or electrical resistivity logs are often used to estimate in situ gas hydrate concentrations in sediment pore space. Estimation errors owing to uncertainties associated with downhole measurements and the parameters for estimation equations (weight in the acoustic ...

Estimation of an opponent's damage preference is illustrated by discussing the sensitivity of stability indices and strike parameters to it and inverting the results to study the sensitivity of estimates to uncertainties in strikes. Costs and stability indices do not generally have the monotonicity and sensitivity needed to ...

Investigated the data demands associated with the marginal maximum likelihood (MML) expected a posterior (EAP) methodology and the precision of the resulting parameter estimates when data fit the underlying model through simulation. Also studied the extent to which a misspecified prior distribution would affect the item and person ...

Accurate Confidence Interval Estimation of Small Area Parameters under the Fay-Herriot Model L area level model, popularly known as Fay-Herriot model. While much of current research is predominantly-1877. 1 #12;based on the Fay and Herriot (1979) model (FH) is one of the most popular tech- niques in small

Predictive modeling of solute transport requires accurate measurement or estimation of geochemical adsorption and ion exchange parameters for a given rock-fluid system. One such parameter is the distribution coefficient (Kd) used to predict the rate of mo...

Any effort to provide precision control for an Autonomous Underwater Vehicle requires an accurate estimation of both the vehicles physical and hydrodynamic parameters. Here a vehicle model for controlled steering behaviors was developed and the hydrodynam...

The accurate characterization of mirror surfaces requires the estimation of two-dimensional distribution functions and power spectra from trend-contaminated profile measurements. The rationale behind this, and our measurement and processing procedures, ar...

Engineering analysis of surface irrigation systems requires a reasonably accurate description of a field's infiltration characteristics. Optimal estimation methods have been proposed for this purpose. These methods pose multiple volume balance equation at various stages of an irrigation event and ...

The geometric method combines a volume and a density function to estimate body segment parameters and has the best opportunity for developing the most accurate models. In the trunk, there are many different tissues that greatly differ in density (e.g., bone versus lung). Thus, the density function for the trunk must be particularly ...

... of dollars estimating the population size of giant pandas (Ailuropoda melanoleuca), the outcomes of such surveys have ... at using fecal microsatellite analysis to enumerate giant pandas (Zhan et al. 2006...

In this work, an optimization method is implemented in an anaerobic digestion model to estimate its kinetic parameters and yield coefficients. This method combines the use of advanced state estimation schemes and powerful nonlinear programming techniques to yield fast and accurate estimates of ...

Optimal experiment design for parameter estimation (OED/PE) has become a popular tool for efficient and accurate estimation of kinetic model parameters. When the kinetic model under study encloses multiple parameters, different optimization strategies can be constructed. ...

The idea of the self-tuning regulator has been extended from single-input, single-output systems to multivariable systems. The least squares criterion is used for process parameter estimation and an optimal look-ahead control strategy for output regulation. To achieve more accurate estimation of the process ...

The estimation of unknown parameters in engineering and scientific models continues to be of great importance in order to validate them to available experimental data. These parameters of concern cannot be known beforehand, but must be measured experimentally, variables such as chemical species concentrations, pressures, or ...

A marginal maximum a posteriori (MMAP) procedure was implemented to estimate item parameters in the generalized graded unfolding model (GGUM). Estimates from the MMAP method were compared with those derived from marginal maximum likelihood (MML) and Markov chain Monte Carlo (MCMC) procedures in a recovery simulation that varied sample ...

... Title : Robust Parameter Estimators for ... The constructive analysis of robustness ... Descriptors : *PARAMETERS, *ESTIMATES, *NONPARAMETRIC ...

... "Estimation and Testing of Parameters of Distributions by Order Statistics" ... "Estimation and Testing of Parameters of Distributions by Order Statistics" ...

The aircraft parameter estimation problem is used to illustrate the utility of parameter estimation,

This paper presents the methodology developed for the estimation of thermodynamic performance and reports the optimum cycle parameters of coal fired CCGT in regenerative and combined cycle configurations using air, helium and carbon dioxide as working gases. A rigorous approach has been followed for the determination of the cycle efficiency by assuming the ...

This paper investigates the applicability as well as the accuracy of artificial neural networks for estimating specific parameters that describe reservoir properties based on seismic data. This approach relies on JPL`s adjoint operators general purpose neural network code to determine the best suited architecture. The authors believe that results presented ...

The estimation of cosmological parameters from a given data set requires a construction of a likelihood function which, in general, has a complicated functional form. We adopt a Gaussian copula and constructed a copula likelihood function for the convergence power spectrum from a weak lensing survey. We show that the parameter ...

We present a numerical scheme for the determination of the optimum fiber length in the cutback method to estimate the dispersion and loss parameters in terahertz waveguides. From a numerical simulation study and observations of the propagation of terahertz waves in wave guides, we found that the optimum fiber length giving the most ...

Quantitative techniques based on ultrasound backscatter are promising tools for ultrasonic tissue characterization. There is a need for fast and accurate processing strategies to obtain consistent estimates. An improved parameter estimation algorithm for the homodyned K distribution was developed based on SNR, ...

The migration of radionuclides in a geologic medium is controlled by the hydrogeologic parameters of the medium such as dispersion coefficient, pore water velocity, retardation factor, degradation rate, mass transfer coefficient, water content, and fraction of dead-end pores. These hydrogeologic parameters are often used to predict the migration of buried ...

The conventional method of thermal modeling of space payloads is expensive and cumbersome. Radiation plays an important part in the thermal modeling of space payloads because of the presence of vacuum and deep space viewing. This induces strong nonlinearities into the thermal modeling process. There is a need for extensive correlation between the model and test data. This thesis presents Online ...

Parameters of the two-parameter logistic model are generally estimated via the expectation-maximization (EM) algorithm by the maximum-likelihood (ML) method. In so doing, it is beneficial to estimate the common prior distribution of the latent ability from data. Full non-parametric ML (FNPML) ...

Hydraulic property measurements often rely on non-linear inversion models whose errors vary between samples. In non-linear physical measurement systems, bias can be directly quantified and removed using calibration standards. In hydrologic systems, field calibration is often infeasible and bias must be quantified indirectly. We use a Monte Carlo error analysis to indirectly quantify spatial bias ...

BackgroundThe use of patient models describing the dynamics of glucose, insulin, and possibly other metabolic species associated with glucose regulation allows diabetes researchers to gain insights regarding novel therapies via simulation. However, such models are only useful when model parameters are effectively estimated with patient data.MethodsThe use ...

Positron emission tomography (PET) is a unique method to investigate physiology in the living body. Kinetic models with kinetic rate constants describe the dynamic radioactive tracer uptake in living tissue. If the variation of the kinetic parameter values within a specific tissue region could be determined accurately, it would give valuable quantitative ...

Positron emission tomography (PET) is a unique method to investigate physiology in the living body. Kinetic models with kinetic rate constants describe the dynamic radioactive tracer uptake in living tissue. If the variation of the kinetic parameter values within a specific tissue region could be determined accurately, it would give valuable quantitative ...

SAR (synthetic aperture radar) processing in the azimuth dimension requires accurate estimation of the Doppler parameters, in order to ensure good quality of high resolution images. A purely analytical derivation of these parameters is presented for the case of a spaceborne side-looking SAR on a nearly circular ...

Moisture content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. This means that accurate estimates of in situ moisture content must be obtained in order to design for the appropriate handling or remediation of a cont...

Many contemporary problems in science ranging from the spread of hazardous chemical or nuclear plumes to protein folding in molecular dynamics to scale up of small scale effects in nanotechnology, to making accurate predictions of the coupled atmosphere-o...

Accurate estimate of land surface temperature, a key parameter in surface energy balance models, requires knowledge of the surface emissivity. Emissivity dependence on soil water content has been already reported and modeled under controlled conditions at the laboratory. This study completes and ext...

... to accurately map the spatial distribution of canopy fuels and model fire behavior over the landscape. The use of airborne laser scanning (LIDAR), a high-resolution active remote sensing technology, ... ...

Covariance error analysis techniques were applied to investigate estimation strategies for the high-low SST mission for accurate local recovery of gravitational fine structure, considering the aliasing effects of unsolved for parameters. Surface density b...

interval #12; and then ask the contoller to apply superthreshold spikes to regulate the system to spiking experiment, in the absence of known model equations. If they are generated according to hypothesis (1 experiment, lack of control over this parameter could conceivably make accurate dimension estimation

The extractability of the phenolic compounds is influenced by their chemical structure, degree of polymerization, and interaction with other components in the matrix. This talk describes the influence of sample preparation parameters (extraction techniques, extraction solvents, temperature, pressu...

Tree-ring chronologies can provide surprisingly accurate estimates of the natural variability of important climate parameters such as precipitation and ... ...

Saturated liquid and vapor densities from the triple point to the critical points for fluorine are reported. These data were derived from experimental PVT isochores and an accurate vapor pressure equation. The critical point parameters were estimated by f...

Vehicle prognostics are used to estimate the remaining useful life of components or subsystems, based on a limited number of measured vehicle parameters. Ideally, sensors would be available for every component and failure mode of interest, such that accur...

The general objective of computer driver adaptive testing is to accurately estimate an individual's position on the underlying trait the test purports to measure. Conventional paper-and-pencil test administration typically suffers from several sources of ...

This paper investigates a technique for the optimal design of helicopter control inputs, in order to provide the most accurate parameter estimates. An existing software package for optimal input design for fixed wing aircraft was modified to design contro...

This thesis investigates the impact of various waveform parameters on the ability to estimate accurately the position of the source of a known data-less emission that is visible to multiple simultaneous collectors. It provides an overview of the basic geo...

On the basis of qualitative theoretical arguments and correlation studies, we find the thermal expansivities, beta , of borides, carbides, nitrides, and oxides can be predicted to within about +-10% based on two parameters: delta E/sub a/, the atomization...

accurate predictions. In the following sections, we present the details of the dryer and the procedure parameter estimation. Application of the proposed method is demonstrated on a household clothes dryer methodology in the following outline. The next section presents a closed- form exact solution to special cases

In this work, a procedure was established to develop a mathematical model considering the effect of temperature on reaction kinetics. Experiments were performed in batch mode in temperatures from 30 to 38�C. The microorganism used was Saccharomyces cerevisiae and the culture media, sugarcane molasses. The objective is to assess the difficulty in updating the kinetic ...

Forward model sensitivities are commonly applied to evaluate the uncertainty in model parameter estimates obtained through inverse analysis. In this case, the forward sensitivity (Jacobian) matrix is applied to compute an approximate representation of the covariance matrix of inverse parameter estimates. However, ...

This paper presents a newly developed algorithm for induction machine rotor speed estimation and parameter detection. The proposed algorithm is based on spectrum analysis of the stator current. The main idea is to find the best fit of motor parameters and rotor slip with the group of characteristic frequencies which are always present ...

Inspired by the motion of electrons in metal conductors in an electric field, we propose a variant of Particle Swarm Optimization (PSO), called Drift Particle Swarm Optimization (DPSO) algorithm, and apply it in estimating the unknown parameters of chaotic dynamic systems. The principle and procedure of DPSO are presented, and the algorithm is used to ...

A new approach is proposed for the a posteriori error estimation of both global spatial and parameter error in parameterized nonlinear reaction-diffusion problems. The technique is based on linear equations relating the linearized spatial and parameter error to the weak residual. Computable local element error indicators are derived ...

Single Event Upset (SEU) vulnerability must be considered in the design of all modern digital electronic systems for use in space. This has resulted in a need to accurately estimate the SEU rate for each type of digital microelectronic component used in the electronic system of any spacecraft on any orbit. This report presents a method of making such ...

Existing forecasting models of auto vehicle miles of travel (VMT) are reviewed, and presents evidence that such models incorrectly omit time cost and spatial form variables is presented. The omission of these variables biases parameter estimates in existing VMT models. More accurate parameter ...

A recently developed implicit estimation procedure (or regression-based method) that uses parameter estimation with B-spline functional representations can determine essentially unbiased estimates of relative permeability functions from dynamic displacement data. In this paper, the authors extend this method to ...

A parametrization of the MNDO method for the Zn atom is proposed. Calculations are performed for zinc-containing molecules and simple complexes. It is shown that the use of the parameters found in this study leads to more accurate estimates of enthalpies of formation of zinc compounds that can be obtained in MNDO calculations with ...

We compute the internal energy of the classical one-component plasma, for values of the Coulomb coupling parameter GAMMA between 1 and 300, by using converged Monte Carlo chains and a more accurate potential approximation than that used by Hansen. The liquid data are fitted to a simple, very accurate four-parameter ...

It is system dynamics that determines the function of cells, tissues and organisms. To develop mathematical models and estimate their parameters are an essential issue for studying dynamic behaviors of biological systems which include metabolic networks, genetic regulatory networks and signal transduction pathways, under perturbation of external stimuli. ...

In the framework of a recently proposed method for in vivo lung morphometry, acinar lung airways are considered as a set of randomly oriented cylinders covered by alveolar sleeves. Diffusion of ³He in each airway is anisotropic and can be described by distinct longitudinal and transverse diffusion coefficients. This macroscopically isotropic but microscopically anisotropic ...

We consider the problem of joint multi-user detection and channel parameter estimation in a space-time bit-interleaved coded modulation (ST-BICM) scheme for an asynchronous DS-CDMA uplink transmission over frequency selective channels. The performance of standard coherent detectors relies on the availability of accurate ...

MOTIVATION: Time-series measurements of metabolite concentration have become increasingly more common, providing data for building kinetic models of metabolic networks using ordinary differential equations (ODEs). In practice, however, such time-course data are usually incomplete and noisy, and the estimation of kinetic parameters from these data is ...

Maximum-likelihood estimation or other probabilistic estimation methods are under-used in many areas of applied gamma-ray imaging, particularly in biomedicine. In this work, we show how to use our understanding of stochastic processes in a scintillation camera and their effect on signal formation to better estimate gamma-ray ...

Root zone soil water content impacts plant water availability and land energy and water balances. Due to an unknown hydrological model error, observation errors and the statistical characteristics of the errors, the most widely used Kalman filter (KF) and its extensions are challenged to retrieve the root zone soil water content using the surface soil water content. If the soil hydraulic ...

Minimum variance estimation for gyroscopic drift parameters, discussing optimal estimation procedure

In this paper we propose an upward correction to the standard error (SE) estimation of theta[subscript ML], the maximum likelihood (ML) estimate of the latent trait in item response theory (IRT). More specifically, the upward correction is provided for the SE of theta[subscript ML] when item parameter estimates ...

In this paper we propose an upward correction to the standard error (SE) estimation of ??_ML, the maximum likelihood (ML) estimate of the latent trait in item response theory (IRT). More specifically, the upward correction is provided for the SE of ??_ML when item parameter ...

This report documents the results for an FY06 ASC Algorithms Level 2 milestone combining error estimation and adaptivity, uncertainty quantification, and probabilistic design capabilities applied to the analysis and design of bistable MEMS. Through the use of error estimation and adaptive mesh refinement, solution verification can be performed in an ...

A method for computing approximate minimum-mean-square-error estimates of histograms from list-mode data for use in dynamic tracer studies is evaluated. Parameters estimated from these histograms are significantly more accurate than those estimated from histograms computed by a commonly used ...

Genetic parameters were estimated using relationships between animals that were based either on pedigree, 43,011 single nucleotide polymorphisms, or a combination of these, considering genotyped and non-genotyped animals. The standard error of the estimates and a parametric bootstrapping procedure was used to investigate sampling ...

A simple model structure of spatial and temporal temperature distribution in human tissue, exposed to electromagnetic heating and surface cooling, is developed. This model, denoted the control model, is useful for thermal dosimetry in hyperthermia cancer therapy. The theoretical control model parameter values for various types of homogeneous tissue are determined from a priori ...

This paper proposes a joint maximum likelihood and Bayesian methodology for estimating Gaussian mixture models. In Bayesian inference, the distributions of parameters are modeled, characterized by hyperparameters. In the case of Gaussian mixtures, the distributions of parameters are considered as Gaussian for the mean, Wishart for the ...

The plant physiological observations during the whole growing season showed a strong seasonal variation of the biochemical parameters in the photosynthesis model, such as maximum carboxylation velocity and maximum rate of electron transport in Farquhar model, which are essential for accurate modeling of photosynthesis and carbon exchange. These ...

In azimuth processing of SAR (Synthetic Aperture Radar) data, the slant range histories of the targets are required. After range compression, the maxima of the responses of point targets are in the so called range migration locus. For spaceborne SAR, the locus traverses a number of range bins. This locus determines where to get the samples needed for the azimuth compression and the phase function ...

With diffusion tensor imaging, the diffusion of water molecules through brain structures is quantified by parameters, which are estimated assuming monoexponential diffusion-weighted signal attenuation. The estimated diffusion parameters, however, depend on the diffusion weighting strength, the b-value, which ...

BackgroundThe importance of stochasticity in cellular processes having low number of molecules has resulted in the development of stochastic models such as chemical master equation. As in other modelling frameworks, the accompanying rate constants are important for the end-applications like analyzing system properties (e.g. robustness) or predicting the effects of genetic perturbations. Prior ...

Estimating the effective dose E with dosemeters calibrated in terms of the personal dose equivalent H(p)(10), one should take into account that the ratio of these two values, i.e. the conversion coefficient C(k), depends essentially on angular and energy parameters of the incident radiation field and is not always close to unity. Introducing the ...

Accurate characterization of the errors in the global astrometric solution for Gaia is essential for making optimal use of the catalogue data. We investigate the structure of the covariance between the estimated astrometric parameters by studying the properties of the astrometric least squares solution. We find that astrometric errors ...