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Houtkooper, Linda, and Jaclyn Maurer. "Calorie Need Estimates." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146643.
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2 pp.The energy content of food is measured in calories. The number of calories, or energy, an athlete needs to maintain weight depends upon: age, body weight, gender, Resting Energy Expenditure (REE) and physical Activity Energy Expenditure (AEE) levels.
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Läuter, Henning. "Empirical Minimax Linear Estimates." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2011/4948/.
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Tran, Manh. "Value-at-risk estimates." Thesis, Aston University, 2018. http://publications.aston.ac.uk/37813/.
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This thesis consists of three empirical essays on the Value-at-Risk (VaR) estimates. The first empirical study (Chapter 2) evaluates the performance of bank VaRs. The second empirical study (Chapter 3) investigates the predictive power of various VaR models using bank data. The third empirical study (Chapter 4) explores VaR estimates with high-frequency data. The first study examines the performance of VaR estimates at seven international banks from 2001 to 2012. Using statistical tests, we find that bank VaRs were conservatively estimated in pre-crisis and post-crisis periods. During financial crisis, while some banks continued to overstate their VaRs, the others significantly underestimated their risk. The potential causes of the poor performance of bank VaRs are also discussed. The second study investigates the predictive power of various VaR models using bank data. We find that the GARCH-based models are superior in estimating bank VaRs in both normal and crisis periods. We conclude that good VaR estimates at banks can be obtained using simple, accessible models rather than the complicated approach or banks’ internal model. Thus, we argue that VaR should not be blamed for misleading risk estimates during financial crisis. The third study evaluates VaR estimates using 5-minute sampling data of WTI Futures. First, we acknowledge the value of high-frequency data on the measure of volatility to characterize the quantile forecast of asset returns. Second, we find that quantile combination can improve the forecast accuracy. With the VaR implication, we show that VaR combination provides more accurate and robust results than individual VaR estimates.
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Millet, Floyd W. "Improving Electromagnetic Bias Estimates." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd525.pdf.
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Watson, J., and M. Sheedy. "Crop Water Use Estimates." College of Agriculture, University of Arizona (Tucson, AZ), 1995. http://hdl.handle.net/10150/210312.
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Irrigation scheduling, by keeping track of irrigation applications, soil storage and crop water use, has been computerized by a number of different individuals. A key component of the computerized methods is the estimation of a reference crop evapotranspiration rate. Complaints about one such method, AZSCHED, led the authors to compare the reference crop evapotranspiration values calculated by AZSCHED with those calculated by a second procedure available used by AZMET. Results of the comparison indicated that no significant difference existed between methods, for either a traditionally "long season", or a contemporary "short season" growing period. AZSCHED did estimate crop water use to be about 5% - 8% more than AZMET, an amount that is not of importance considering the irrigation inefficiencies created by field non-uniformities. Experience by the authors indicates that inappropriate selection of irrigation efficiencies and/or soil water holding capacity may be the main cause of user complaints.
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Wall, Nathan Lane. "Augmented testing and effects on item and proficiency estimates in different calibration designs." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/1100.
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Broadening the term augmented testing to include a combination of multiple measures to assess examinee performance on a single construct, the issues of IRT item parameter and proficiency estimates were investigated. The intent of this dissertation is to determine if different IRT calibration designs result in differences to item and proficiency parameter estimates and to understand the nature of those differences.
Examinees were sampled from a testing program in which each examinee was administered three mathematics assessments measuring a broad mathematics domain at the high school level. This sample of examinees was used to perform a real data analysis to investigate the item and proficiency estimates. A simulation study was also conducted based upon the real data.
The factors investigated for the real data study included three IRT calibration designs and two IRT models. The calibration designs included: separately calibrating each assessment, calibrating all assessments in one joint calibration, and separately calibrating items in three distinct content areas. Joint calibration refers to the use of IRT methodology to calibrate two or more tests, which have been administered to a single group, together so as to place all of the items on a common scale. The two IRT models were the one- and three-parameter logistic model. Also investigated were five proficiency estimators: maximum likelihood estimates, expected a posteriori, maximum a posteriori, summed-score EAP, and test characteristic curve estimates. The simulation study included the same calibration designs and IRT models but the data were simulated with varying levels of correlations among the proficiencies to determine the affect upon the item parameter estimates.
The main findings indicate that item parameter and proficiency estimates are affected by the IRT calibration design. The discrimination parameter estimates of the three-parameter model were larger when calibrated under the joint calibration design for one assessment but not for the other two. Noting that equal item discrimination is an assumption of the 1-PL model, this finding raises questions as to the degree of model fit when the 1-PL model is used. Items on a second assessment had lower difficulty parameters in the joint calibration design while the item parameter estimates of the other two assessments were higher. Differences in proficiency estimates between calibration designs were also discovered, which were found to result in examinees being inconsistently classified into performance categories. Differences were observed in regards to the choice of IRT model. Finally, as the level of correlation among proficiencies increased in the simulation data, the differences observed in the item parameter estimates were decreased.
Based upon the findings, IRT item parameter estimates resulting from differing calibrations designs should not be used interchangeably. Practitioners who use item pools should base the pool refreshment calibration design upon the one used to originally create the pool. Limitations to this study include the use of a single dataset consisting of high school examinees in only one subject area, thus the degree of generalization regarding research findings to other content areas of grade levels should be made with caution.
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Sereevinyayut, Piya. "On estimate aggregation : studies of how decision makers aggregate quantitative estimates in three different cases." Doctoral thesis, Universitat Pompeu Fabra, 2013. http://hdl.handle.net/10803/125062.
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This dissertation examines how people aggregate quantitative advices to reach their own estimates. Each chapter explores a different situation that could affect how advices are evaluated, and consequentially how advices will be combined. The first chapter demonstrates that people measure advices' extremity degrees by anhoring upon the advice set's median. It also shows that, unlike multiplicative scaling, additive scaling of advices affects how outliers are perceived. The second chapter deals with advices that are obtained serially. The results reveals that whether people execute the aggregation sequentially or only once at the end of the series affects how an outlier in the series is detected and combined. The third chapter studies how people revise their own estimates with advices of others, and finds that people revise more if they appear a dissensus. Consequentially having multiple advices can attenuate of the effect of egocentricity and improve accuracy of revisions compared to having only a single adviceAquesta tesi estudia com les persones agreguen consells quantitatius per arribar a les seves pròpies estimacions. Cada capítol explora una situació diferent que podria afectar com s'avaluen els consells, i en conseqüència com es combinen aquests consells. El primer capítol demostra que les persones mesuren els graus extrems dels consells per ancoratge a la mediana del conjunt de consells. També es mostra que, en comptes d’una escala multiplicadora,l’ escala additiva dels consells afecta a com es perceben els valors atípics. El segon capítol tracta de consells que s'obtenen en sèrie. Els resultats revelen que si les persones executen l'agregació seqüencialment o només una vegada al final de la sèrie, afecta a com es detecten i es combinen els valors atípics en la sèrie. El tercer capítol estudia com les persones revisen les seves estimacions a partir consells dels altres, i es troba que les persones revisen més si es troben en un dissens. Conseqüentment, tenir consells múltiples pot atenuar l'efecte d'egocentrisme i millorar la precisió de les revisions si es compara en tenir només un únic consell.
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Domingo, Salazar Carlos. "Endpoint estimates via extrapolation theory." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/396143.
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In this thesis, we study different variants of Rubio de Francia’s extrapolation that allow us to obtain estimates near L1. This theory is subsequently applied to deduce enpoint boundedness for the Bochner-Riesz operator and other classes of multipliers. We also present results related to Yano’s extrapolation on Lorentz spaces and how it can be related to the theory of weights.En aquesta tesi, estudiem variants de l’extrapolació de Rubio de Francia que permetin obtenir estimacions a prop de l’espai L1. Aquesta teoria l’apliquem després per deduïr acotacions a l’extrem per l’operador de Bochner-Riesz i altres classes de multiplicadors. També presentem altres resultats sobre teoria d’extrapolació de tipus Yano en espais de Lorentz i sobre com es pot relacionar amb la teoria de pesos.
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Bilyk, Dmytro. "Distributional estimates for multilinear operators." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4139.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (May 23, 2006) Vita. Includes bibliographical references.
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Corredor, Orlando A. "Anthropometric estimates for Colombian adults." FIU Digital Commons, 1994. http://digitalcommons.fiu.edu/etd/2643.
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Knowledge of anthropometric dimensions is important for the design of workspaces and equipment. In a developing country, such as Colombia, no anthropometric survey for Colombian adults has yet been published. Therefore, the purpose of this study is to assemble a Colombian adult anthropometric data set sufficiently accurate for design applications. An anthropometric survey was conducted on 134 Colombian adults living in South Florida. Twenty body dimensions were measured. Moreover, an anthropometric estimation method was selected, described and validated to be used as a reference when measurement of the user population is not possible. Anthropometric estimates, using the scaling ratio method, and those obtained in the survey were analyzed and compared with other population data. Tables are assembled and dimensional models are suggested which may be used as a design tool.
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Salar, Kemal. "Sample size for correlation estimates." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27248.
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Yitayew, Muluneh. "Reference Evapotranspiration Estimates for Arizona." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/602135.
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Rodríguez, Alexandra Lemus. "Spectral estimates for Schrödinger operators." Thesis, Connect to online version, 2008. http://proquest.umi.com/pqdweb?did=1675127001&sid=3&Fmt=2&clientId=10306&RQT=309&VName=PQD.
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Potapov, Denis, and denis potapov@flinders edu au. "Lipschitz and commutator estimates, a unified approach." Flinders University. School of Informatics and Engineeering, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20070723.110059.
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The subject of the thesis is the study of operator functions in the setting of symmetric operator spaces. In this latter setting, it is of great importance to analyze the properties of so-called operator functions A --> f(A), where the variable A is a self-adjoint operator and f is a complex-valued Borel function on the real line. The thesis study the question of differentiability of this type of operator functions. The latter question is intimately related to the study of commutators. Text not only extends existing results to the setting of unbounded self-adjoint linear operators, but it is also shown that this can be obtained via a unified approach utilizing the left regular representation of von Neumann algebras.
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Fusco, Chelsea Sloan. "A Game Theoretic Explanation of Art Auction Experts’ Pre-Sale Estimates: How Estimates Alter Auction Success." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/scripps_theses/791.
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This paper examines the relationship between auction outcomes and pre-sale estimates. Using data from Blouin Arts Sales Index this paper examines 700 realized prices for Picasso works over the last five months of 2015. After considering many estimation inadequacies, it is determined that experts are publishing accurate and unbiased pre-sale valuations. For works unsold, the revenue lost to “buy ins” is offset by the excess revenue earned from current estimate publishing strategies.
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Mote, Shekhar Raj. "EVALUATION OF STATE-OF-THE-ART PRECIPITATION ESTIMATES: AN APPROACH TO VALIDATE MULTI-SATELLITE PRECIPITATION ESTIMATES." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2364.
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Availability of precipitation data is very important in every aspect related to hydrology. Readings from the ground stations are reliable and are used in hydrological models to do various analysis. However, the predictions are always associated with uncertainties due to the limited number of ground stations, which requires interpolation of the data. Meanwhile, groundbreaking approach in capturing precipitation events from vantage point through satellites in space has created a platform to not only merge ground data with satellite estimates to produce more accurate result, but also to find the data where ground stations are not available or scarcely available. Nevertheless, the data obtained through these satellite missions needs to be verified on its temporal and spatial resolution as well as the uncertainties associated before we make any decisions on its basis. This study focuses on finding and evaluating data obtained from two multi-satellite precipitation measurements missions: i) Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) ii) Global Precipitation Measurement (GPM) mission. GPM is the latest mission launched on Feb 28, 2014 after the successful completion of TRMM mission which collected valuable data for 17 years since its launch in November 1997. Both near real time and final version precipitation products for TMPA and GPM are considered for this study. Two study areas representing eastern and western parts of the United States of America (USA) are considered: i) Charlotte (CLT) in North Carolina ii) San Francisco (SF) in California. Evaluation is carried out for daily accumulated rainfall estimates and single rainfall events. Statistical analysis and error categorization of daily accumulated rainfall estimates were analyzed in two parts: i) Ten yeas data available for TMPA products were considered for historical analysis ii) Both TMPA and GPM data available for a ten-month common period was considered for GPM Era analysis. To study how well the satellite estimates with their finest temporal and spatial resolution capture single rainfall event and to explore their engineering application potential, an existing model of SF watershed prepared in Infoworks Integrated Catchment Model (ICM) was considered for hydrological simulation. Infoworks ICM is developed and maintained by Wallingford Software in the UK and SF watershed model is owned by San Francisco Public Works (SFPW). The historical analysis of TMPA products suggested overestimation of rainfall in CLT region while underestimation in SF region. This underestimation was largely associated with missed-rainfall events and negative hit events in SF. This inconsistency in estimation was evident in GPM products as well. However, in the study of single rainfall events with higher magnitude of rainfall depth in SF, the total rainfall volume and runoff volume generated in the watershed were over-estimated. Hence, satellite estimates in general tends to miss rainfall events of lower magnitude and over-estimate rainfall events of higher magnitude. From statistical analysis of GPM Era data, it was evident that GPM has been able to correct this inconsistency to some extent where it minimized overestimation in CLT region and minimized negative error due to underestimation in SF. GPM products fairly captured the hydrograph shape of outflow in SF watershed in comparison to TMPA. From this study, it can be concluded that even though GPM precipitation estimates could not quiet completely replace ground rain gage measurements as of now, with the perpetual updating of algorithms to correct its associated error, it holds realistic engineering application potential in the near future.
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Gentile, Giovanni. "Eigenvalue estimates for the Laplace operator /." [S.l.] : [s.n.], 1998. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12770.
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Kirby, Christopher William. "An investigation of stratified population estimates." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq23364.pdf.
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Wiebe, Jonathan Andrew. "Texture estimates of operational forestry parameters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/MQ35026.pdf.
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Favorite, Jeffrey Alan. "Variational estimates of point kinetics parameters." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/16756.
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O'Connell, W. Richard Jr. "Estimates for the St. Petersburg game." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/28858.
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Rosler, Frank. "Norm-resolvent estimates and perforated domains." Thesis, Durham University, 2018. http://etheses.dur.ac.uk/12736/.
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In this thesis we are concerned with norm-resolvent estimates for unbounded linear operators. The text is structured into four parts. The first two parts contain mathematical preliminaries, reviews of previous work and an introduction into the two results which constitute parts three and four. In the third part we are concerned with the non-normal Schrödinger operator H = −∆+V on L2(Rd), where Re(V(x))≥c|x|2−b for some c,b>0. The spectrum of this operator is discrete and its real part is bounded below by −b. In general, the ε-pseudospectrum of H will have an unbounded component for any ε > 0 and thus will not approximate the spectrum in a global sense. By exploiting the fact that the semigroup exp(−tH) is immediately compact, we show a complementary result, namely that for every δ > 0, R > 0 there exists an ε > 0 such that the ε-pseudospectrum is contained in the union of the half plane {Re(z)>R} and disks of radius δ around the eigenvalues. In particular, the unbounded component of the pseudospectrum escapes towards +∞ as ε decreases. Additionally, we give two examples of non-selfadjoint Schrödinger operators outside of our class and study their pseudospectra in more detail. In Part IV, we prove norm-resolvent convergence, as ε→0, for the operator −∆ in domain perforated ε-periodically, to the limit operator −∆+μ on L2(Ω), where μ∈C is a constant depending on the choice of boundary conditions on the holes (we consider Dirichlet, Neumann and Robin boundary conditions). This is an improvement of previous results by [Cioranescu-Murat(1997)], [Kaizu(1985)], which show strong resolvent convergence. In particular, our result implies Hausdorff convergence of the spectrum of the resolvent for the perforated domain problem.
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Roseborough, James B. "Aiding human operators with state estimates." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14550.
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Hadjiharitou, Dimitris. "Improving estimates of structural seismic motion." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82815.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 67-68).
A critical field in civil engineering is the evaluation of structural damage after severe earthquakes. Seismic events are taken into serious consideration in areas of the world such as California and countries adjacent to the Mediterranean. After these events, structural engineers are called to evaluate structural damage and to enhance the structure's future capabilities and serviceability. Due to the large number of structures and the significant time needed to evaluate the potential damage in each structure, other methods for structural behavior observation were needed. One of those has been established in the late 1950's and had to do with the implementation of electronic monitoring devices in structures. This dissertation evaluates the placement of today's motion sensing instruments and proposes an algorithm that proposes optimized instrumentation schemes in buildings. The dissertation starts with a presentation and critique of today's instrumentation techniques and suggests how they could be optimized or refined to get a better approximation of the structure's behavior. Furthermore, optimization schemes provided by the literature are presented. In addition, the author proposes an algorithm that estimates and proposes instrumentation schemes of buildings. The proposed instrumentation schemes take into consideration all three dimensions. The algorithm is described by a flow chart and mathematical equations and is implemented in MATLAB. To check the validity of the algorithm, case studies are conducted. These case studies are based on finite element models of buildings that were hit by the Northridge earthquake and were instrumented during that period. Actual recorded accelerations from the base of the structures have been used to conduct the case studies. Finally, the results of these case studies are presented. The results present the exact positions of the sensors in order to get better approximation of the structure's behavior in a cost effective manner. In addition, an evaluation is conducted for the estimation of the behavior of the algorithm on different earthquake data.
by Dimitris Hadjiharitou.
M.Eng.
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Wagner, Laurent. "MINESTIS, the route to resource estimates." Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-181676.
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Minestis software allows geological domain modeling and resource estimation through an efficient and simplified geostatistics-based workflow. It has been designed for all those, geologists, mining engineers or auditors, for whom quick production of quality models is at the heart of their concerns.
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Sweeting, Brandon S. "Novel Bellman Estimates for Ap Weights." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1627659615965755.
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De, Capua Antonio. "Hyperbolic volume estimates via train tracks." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:426f7186-e881-482b-90d8-5cbb9b9a38b7.
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In this thesis we describe how to estimate the distance spanned in the pants graph by a train track splitting sequence on a surface, up to multiplicative and additive constants. If some moderate assumptions on a splitting sequence are satisfied, each vertex set of a train track in it will represent a vertex of a graph which is naturally quasi-isometric to the pants graph; moreover the splitting sequence gives an edge-path in this graph so, more precisely, our distance estimate holds between the extreme points of this path. The present distance estimate is inspired by a result of Masur, Mosher and Schleimer for distances in the marking graph. However, we can apply their line of proof only after some manipulation of the splitting sequence: a rearrangement, changing the order the elementary moves are performed in, so that the ones producing Dehn twists are brought together; and then an untwisting, which suppresses the majority of these latter moves to give a new sequence, which does not end with the same track as before, but does not include any portion that is almost stationary in the pants graph. The required distance is then, up to constants, the number of splits occurring in the untwisted sequence. A consequence of our main theorem together with a result of Brock is that, given a pseudo-Anosov self-diffeomorphism Ï of a surface S, the maximal splitting sequence introduced by Agol gives us an estimate for the hyperbolic volume of the mapping torus built from S and Ï. There are also some interesting consequences for the hyperbolic volume of a solid torus minus a closed braid, via a machinery employed by Dynnikov and Wiest.
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Disney, Nicholas. "Model-based estimates of UK immigration." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/374938/.
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Munster, Drayton William. "Robust Parameter Inversion Using Stochastic Estimates." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/96399.
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For parameter inversion problems governed by systems of partial differential equations, such as those arising in Diffuse Optical Tomography (DOT), even the cost of repeated objective function evaluation can be overwhelming. Despite the linear (in the state variable) nature of the DOT problem, the nonlinear parameter inversion process is dominated by the computational burden of solving a large linear system for each source and frequency. To compute the Jacobian for use in Newton-type methods, an adjoint solve is required for each detector and frequency. When a three-dimensional tomography problem may have nearly 1,000 sources and detectors, the computational cost of an optimization routine is a large burden. While techniques from model order reduction can partially alleviate the computational cost, obtaining error bounds in parameter space is typically not feasible. In this work, we examine two different remedies based on stochastic estimates of the objective function.
In the first manuscript, we focus on maximizing the efficiency of using stochastic estimates by replacing our objective function with a surrogate objective function computed from a reduced order model (ROM). We use as few as a single sample to detect a misfit between the full-order and surrogate objective functions. Once a sufficiently large difference is detected, it is necessary to update the ROM to reduce the error. We propose a new technique for improving the ROM with very few large linear solutions. Using this techniques, we observe a reduction of up to 98% in the number of large linear solutions for a three-dimensional tomography problem.
In the second manuscript, we focus on establishing a robust algorithm. We propose a new trust region framework that replaces the objective function evaluations with stochastic estimates of the improvement factor and the misfit between the model and objective function gradients. If these estimates satisfy a fixed multiplicative error bound with a high, but fixed, probability, we show that this framework converges almost surely to a stationary point of the objective function. We derive suitable bounds for the DOT problem and present results illustrating the robust nature of these estimates with only 10 samples per iteration.Doctor of Philosophy
For problems such as medical imaging, the process of reconstructing the state of a system from measurement data can be very expensive to compute. The ever increasing need for high accuracy requires very large models to be used. Reducing the computational burden by replacing the model with a specially constructed smaller model is an established and effective technique. However, it can be difficult to determine how well the smaller model matches the original model. In this thesis, we examine two techniques for estimating the quality of a smaller model based on randomized combinations of sources and detectors. The first technique focuses on reducing the computational cost as much as possible. With the equivalent of a single randomized source, we show that this estimate is an effective measure of the model quality. Coupled with a new technique for improving the smaller model, we demonstrate a highly efficient and robust method. The second technique prioritizes robustness in its algorithm. The algorithm uses these randomized combinations to estimate how the observations change for different system states. If these estimates are accurate with a high probability, we show that this leads to a method that always finds a minimum misfit between predicted values and the observed data.
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Sander, Jacob Victor. "Vertical height estimates of pitched balls." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1576607357582938.
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Gruen, Karen Davis. "Mesoscale temperature estimates for Western Virginia." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020343/.
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Yang, Wen-Huei. "Approximate interval estimates for mechanical reliability." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA241071.
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Thesis (M.S. in Operations Research)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Woods, W.M. Second Reader: Bailey, Michael. "September 1990." Description based on title screen as viewed on December 15, 2009. DTIC Identifier(s): Intervals, Estimates, Parametric Analysis. Author(s) subject terms: Reliability, Confidence Limit, Parametric, Normal, Unknown Means and Variances. Includes bibliographical references (p. 53-54). Also available in print.
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Dahmani, Kamilia. "Weighted LP estimates on Riemannian manifolds." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30188/document.
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Cette thèse s'inscrit dans le domaine de l'analyse harmonique et plus exactement, des estimations à poids. Un intérêt particulier est porté aux estimations Lp à poids des transformées de Riesz sur des variétés Riemanniennes complètes ainsi qu'à l'optimalité des résultats en terme de la puissance de la caractéristique des poids. On obtient un premier résultat (en terme de la linéarité et de la non dépendance de la dimension) sur des espaces pas nécessairement de type homogène, lorsque p = 2 et la courbure de Bakry-Emery est positive. On utilise pour cela une approche analytique en exhibant une fonction de Bellman concrète. Puis, en utilisant des techniques stochastiques et une domination éparse, on démontre que les transformées de Riesz sont bornées sur Lp, pour p ∈ (1, +∞) et on déduit également le résultat précèdent. Enfin, on utilise un changement élégant dans la preuve précèdente pour affaiblir l'hypothèse sur la courbure et la supposer minoréeThe topics addressed in this thesis lie in the field of harmonic analysis and more pre- cisely, weighted inequalities. Our main interests are the weighted Lp-bounds of the Riesz transforms on complete Riemannian manifolds and the sharpness of the bounds in terms of the power of the characteristic of the weights. We first obtain a linear and dimensionless result on non necessarily homogeneous spaces, when p = 2 and the Bakry-Emery curvature is non-negative. We use here an analytical approach by exhibiting a concrete Bellman function. Next, using stochastic techniques and sparse domination, we prove that the Riesz transforms are Lp-bounded for p ∈ (1, +∞) and obtain the previous result for free. Finally, we use an elegant change in the precedent proof to weaken the condition on the curvature and assume it is bounded from below
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Pearl, Robert Gilfillan. "Factors affecting the accuracy of quantity surveyors pre-tender price forecasts in South Africa." Master's thesis, Faculty of Engineering and the Built Environment, 1992. https://hdl.handle.net/11427/32013.
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The primary purpose of this dissertation is to identify the factors which affect the accuracy of South African quantity surveyors' pre-tender price forecasts. Prices submitted by bidders at the tender submission stage of project development are utilised as the best practical measure for establishing the degree of accuracy achieved. A large number of design price forecasting techniques are available to estimators. Many of the techniques used in the early stages of design are applicable for providing budget
amounts for design control purposes, whilst others are more· appropriate for forecasting anticipated tender sums. Features of price forecasting requiring attention at all stages of design development are identified as: (i) the influence of uncertainty inherent in the process, (ii) data / information availability and management, and (iii) the utilization of tendering data by means of 'feedback' systems. The factors affecting the accuracy of price forecasts are examined by means of a literature study, opinion surveys of estimators and empirical research on the results of estimate /tender comparisons. The relevance of the question of pre-tender price forecasts is demonstrated by the results of the study which indicates that the accuracy and reliability of South African quantity surveyors' estimates produced at the tender stage is inferior to that generally found overseas and do not meet the expectations of architects and clients. The conclusions drawn from this study indicate a distinct potential for improvement in
early design stage price management.
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Stubblefield, Cedrick L. "Microwave estimates of the extratropical transitions process." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Mar%5FStubblefield.pdf.
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Longetti, Angelica. "Burkholder's Sharp Lp estimates for martingale transforms." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12514/.
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L’argomento della tesi è una disuguaglianza Lp per trasformate di martingala. La trasformata di una martingala Xn si ottiene moltiplicando le sue differenze per una sequenza prevedibile Hn, ottenendo così la sequenza delle differenze della martingala trasformata (H · X)n.
E’ interessante che siano state identificate le stime esatte in Lp per queste trasformate. Nella presente tesi si discuterà sulla tecnica di dimostrazione, dovuta al
probabilista Burkholder. Questa si sviluppa due parti: (i) la prova della disuguaglianza tramite una "funzione di Bellman" a due variabili con determinate proprietà e (ii) la prova dell’esistenza di tale funzione, che viene costruita esplicitamente. Ciò che è sorprendente è che Burkholder sia stato in grado di individuarla.
La ricerca si è successivamente ampliata ad altre disuguaglianze, con applicazioni a vari problemi di analisi stocastica, generalizzando i risultati e le idee di Burkholder in differenti contesti. Si tratta di un campo di ricerca corrente in continuo sviluppo.
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Vagharshakyan, Armen. "Estimates for discrepancy and Calderon-Zygmund operators." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34706.
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Reguera, Rodriguez Maria del Carmen. "Sharp weighted estimates for singular integral operators." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39522.
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The thesis provides answers, in one case partial and in the other final, to two conjectures in the area of weighted inequalities for Singular Integral Operators. We study the mapping properties of these operators in weighted Lebesgue spaces with weight w. The novelty of this thesis resides in proving sharp dependence of the operator norm on the Muckenhoupt constant associated to the weigth w for a rich class of Singular Integral operators. The thesis also addresses the end point case p=1, providing counterexamples for the dyadic and continuous settings.
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Tacy, Melissa Evelyn, and melissa tacy@anu edu au. "Semiclassical Lp Estimates for Quasimodes on Submanifolds." The Australian National University. Department of Mathematics, College of Physical & Mathematical Sciences, 2010. http://thesis.anu.edu.au./public/adt-ANU20100622.150105.
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Motivated by the desire to understand classical-quantum correspondences, we study concentration phenomena of approximate eigenfunctions of a semiclassical pseudodifferential operator $P(h)$. Such eigenfunctions appear as steady state solutions of quantum systems. Here we think of $h$ as being a small parameter such that $h^{2}$ is inversely proportional to the energy of such a system. As we understand classical mechanics to be the high energy (or small $h$) limit of quantum mechanics we expect the behaviour of eigenfunctions $u(h)$ for small $h$ to be related to properties of the associated classical system. In particular we study the connection between the classical flow and the quantum concentration properties.
The flow, $(x(t),\xi(t))$, of a classical system describes the system's motion through phase space where $x(t)$ is interpreted as position and $\xi(t)$ is interpreted as momentum. In the quantum regime we think of an eigenfunction as being composed of highly localised packets moving along bicharacteristics of the classical flow. With this intuition we relate concentration of eigenfunctions in a region to the time spent by projections of bicharacteristics there.
We use the $L^{p}$ norm of $u$ when restricted to submanifolds as a measure of concentration. A high $L^{p}$ norm particularly for small $p$ is indicative of concentration near the submanifold.
We reduce the estimates on eigenfunctions to operator norm estimates on associated evolution operators. Using the semiclassical analysis methods developed in Chapter 3 we express these evolution operators as oscillatory integral operators. Chapter 2 covers the technical background needed to work with such operators. In Chapter 4 we determine eigenfunction estimates for eigenfunctions restricted to a smooth embedded submanifold $Y$ of arbitrary dimension. If $Y$ is a hypersurface, the greatest concentration occurs when there are bicharacteristics of the classical flow embedded in $Y$. In Chapter 5 we assume that projections of such bicharacteristics can be at worst simply tangent to $Y$ and thereby obtain better results for small values of $p$.
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Jacoby, Henry D. "Informing Climate Policy Given Incommensurable Benefits Estimates." MIT Joint Program on the Science and Policy of Global Change, 2004. http://hdl.handle.net/1721.1/4057.
Full textAbstract:
The determination of long-term goals for climate policy, or of near-term mitigation effort, requires a shared conception among nations of what is at stake. Unfortunately, because of different attitudes to risk, problems of valuing non-market effects, and disagreements about aggregation across rich and poor nations, no single benefit measure is possible that can provide commonly accepted basis for judgment. In response to this circumstance, a portfolio of estimates is recommended, including global variables that can be represented in probabilistic terms, regional impacts expressed in natural units, and integrated monetary valuation. Development of such a portfolio is a research task, and the needed program of work suggested.Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).
Results cited from the MIT Joint Program on the Science and Policy of Global Change were developed with the support of the US Department of Energy, Office of Biological and Environmental Research [BER] (DE-FG02-94ER61937) the US Environmental Protection Agency (X-827703-01-0), the Electric Power Research Institute, and by a consortium of industry and foundation sponsors.
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Pedersen, Henrik Laurberg. "Uniform estimates of polynomials by logarithmic sums." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39978.
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It is well known that the size of a polynomial is controlled in the whole complex plane by the logarithmic integral of the polynomial. In the present thesis we show that the logarithmic sum, a discrete analogue of the logarithmic integral, can be used, with suitable precautions, for the same purpose. We obtain uniform estimates of polynomials having sufficiently small logarithmic sums. In these estimates, dependence of the polynomials is expressed entirely through the logarithmic sums of the polynomials.This result was originally established by Paul Koosis in 1966. The proof that we present here is, however, new. We use a suitable version of a so-called multiplier theorem. Theorems of this kind were first published by Beurling and Malliavin in 1962. The particular version that we need is based on least superharmonic majorants and harmonic estimation in slit regions and is due to Koosis.
We extend the result to entire functions of exponential type less than a certain numerical constant (approximately one third). This extension is new and is based on the ideas behind the proof for polynomials.
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Perez, Marco A. "Improving precipitation estimates from dual-wavelength radars." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79112.
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Dual-wavelength radars can, in principle, provide extra information to help in the estimation of precipitation. One method would be to use the differential attenuation measured between the two frequencies of the radar as an indication of the rain rate. Microwave attenuation is widely regarded as a good estimator of the intensity of precipitation. The theory of microwave attenuation is presented, as well as an estimation of the error sources involved in the measurement of attenuation with dual-wavelength radars. Two long-time datasets of disdrometer data are used to test the feasibility of tuning the radar Z - R relationship by measuring the relation between reflectivity and X-band attenuation. As an interesting fact, a surprising proportionality between these two variables is found for higher intensities of precipitation (Z > 40 dBZ). This finding limits the capabilities of dual-wavelength radars to use attenuation as a second parameter, since at higher reflectivities X-band attenuation is almost equivalent to reflectivity.
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Iakovlev, Alexander. "On estimates of constants for maximal functions." Doctoral thesis, KTH, Matematik (Avd.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145704.
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In this work we will study Hardy-Littlewood maximal function and maximal operator, basing on both classical and most up to date works. In the first chapter we will give definitions for different types of those objects and consider some of their most important properties. The second chapter is entirely devoted to an overview of the fundamental properties of Hardy-Littlewood maximal function, which are strong (p, p) and weak (1, 1) inequalities. Here we list the most actual results on this inequalities in correspondence to the way the maximal func-tion is defined. The third chapter presents the theorem on asymptotic behavior of the lower bound of the constant in the weak-type (1, 1) inequality for the maximal function associated with cubes of Rd, then the dimension d tends to infinity. In the last chapter a method forcomputing constant c, appearing in the main theorem of chapter 3, is given.QC 20140527
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Tao, Zuoyu. "Improved uncertainty estimates for geophysical parameter retrieval." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61516.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 167-169).
Algorithms for retrieval of geophysical parameters from radiances measured by instruments onboard satellites play a large role in helping scientists monitor the state of the planet. Current retrieval algorithms based on neural networks are superior in accuracy and speed compared to physics-based algorithms like iterated minimum variance (IMV). However, they do not have any form of error estimation, unlike IMV. This thesis examines the suitability of several different approaches to adding in confidence intervals and other methods of error estimation to the retrieval algorithm, as well as alternative machine learning methods that can both retrieve the parameters desired and assign error bars. Test datasets included both current generation operational instruments like AIRS/AMSU, as well as a hypothetical future hyper- spectral microwave sounder. Mixture density networks (MDN) and Sparse Pseudo Input Gaussian processes (SPGP) were found to be the most accurate at variance prediction. Both of these are novel methods in the field of remote sensing. MDNs also had similar training and testing time to neural networks, while SPGPs often took three times as long to train in typical cases. As a baseline, neural networks trained to estimate variance were also tested, but found to be lacking in accuracy and reliability compared to the other methods.
by Zuoyu Tao.
M.Eng.
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Kuo, Yu-Ting 1966. "Some estimates of the value of software." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/35991.
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Sande, Olow. "Boundary Estimates for Solutions to Parabolic Equations." Doctoral thesis, Uppsala universitet, Matematiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-281451.
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This thesis concerns the boundary behavior of solutions to parabolic equations. It consists of a comprehensive summary and four scientific papers. The equations concerned are different generalizations of the heat equation. Paper I concerns the solutions to non-linear parabolic equations with linear growth. For non-negative solutions that vanish continuously on the lateral boundary of an NTA cylinder the following main results are established: a backward Harnack inequality, the doubling property for the Riesz measure associated with such solutions, and the Hölder continuityof the quotient of two such solutions up to the boundary. Paper 2 concerns the solutions to linear degenerate parabolic equations, where the degeneracy is controlled by a Muckenhoupt weight of class 1+2/n. For non-negative solutions that vanish continuously on the lateral boundary of an NTA cylinder the following main results are established: a backward Harnack inequality, the doubling property for the parabolic measure, and the Hölder continuity of the quotient of two such solutions up to the boundary. Paper 3 concerns a fractional heat equation. The first main result is that a solution to the fractional heat equation in Euclidean space of dimension n can be extended as a solution to a certain linear degenerate parabolic equation in the upper half space of dimension n+1. The second main result is the Hölder continuity of quotients of two non-negative solutions that vanish continuously on the latteral boundary of a Lipschitz domain. Paper 4 concerns the solutions to uniformly parabolic linear equations with complex coefficients. The first main result is that under certain assumptions on the opperator the bounds for the single layer potentials associated to the opperator are bounded. The second main result is that these bounds always hold if the opperator is realvalued and symmetric.
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Strasser, Helmut. "Perturbation invariant estimates and incidental nuisance parameters." Institut für Statistik und Mathematik, WU Vienna University of Economics and Business, 1996. http://epub.wu.ac.at/1138/1/document.pdf.
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It is shown (Proposition (3.9)) that the asymptotic information bound which is valid for the estimation of a parameter in the structure (mixture) model remains valid in the functional model (incidental nuisance parameters) if only perturbation symmetric estimators (Definition (3.6)) are admitted. Pertur- bation symmetry is a property which is closely related to permutation symmetry (Theorem (3.4)). In particular, equicontinuous functions of empirical processes are perturbation symmetric (Theorem (3.3)). Thus, the results of this paper continue a discussion initiated by Bickel and Klaassen (1986), Pfanzagl (1993) and Strasser (1996) on permutation symmetry of estimators and the exclusion of superefficiency in the functional model. (authors' abstract)Series: Forschungsberichte / Institut für Statistik
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Prazeres, Disson Soares dos. "Improved regularity estimates in nonlinear elliptic equations." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13536.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorConselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
In this work we establish local regularity estimates for at solutions to non-convex fully nonlinear elliptic equations and we study cavitation type equations modeled within coef- icients bounded and measurable.
Neste trabalho estabelecemos estimativas de regularidade local para soluÃÃes "flat" de equaÃÃes elÃpticas totalmente nÃo-lineares nÃo-convexas e estudamos equations do tipo cavidade com coeficientes meramente mensurÃveis.
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Takahara, Jyunichi. "WEGNER ESTIMATES FOR GENERALIZED ALLOY TYPE POTENTIALS." Kyoto University, 2013. http://hdl.handle.net/2433/180367.
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Kyoto University (京都大学)0048
新制・課程博士
博士(人間・環境学)
甲第17837号
人博第658号
新制||人||158(附属図書館)
25||人博||658(吉田南総合図書館)
30652
京都大学大学院人間・環境学研究科共生人間学専攻
(主査)教授 上木 直昌, 教授 森本 芳則, 教授 髙﨑 金久
学位規則第4条第1項該当
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Toloza, Julio Hugo. "Exponentially Accurate Error Estimates of Quasiclassical Eigenvalues." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/30072.
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We study the behavior of truncated Rayleigh-Schröodinger series for the low-lying eigenvalues of the time-independent Schröodinger equation, when the Planck's constant is considered in the semiclassical limit.
Under certain hypotheses on the potential energy, we prove that, for any given small value of the Planck's constant, there is an optimal truncation of the series for the approximate eigenvalues, such that the difference between an approximate and actual eigenvalue is smaller than an exponentially small function of the Planck's constant. We also prove the analogous results concerning the eigenfunctions.Ph. D.