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Bonded brickwork walls of large thickness constructed with double or triple bricks are common in loadbearing historical masonry structures in many regions which require interventions and compression capacity evaluation. However, current design provisions for compression capacity prediction are primarily based on single brick prisms and wallette specimens. Due to anisotropic nature of masonry, the strength and deformation characteristics of bonded brickwork with double and triple brick thicknesses are different to the single leaf brickwork; and their design using the provisions of single leaf bonded brickwork specimens may be un-conservative. To expand the knowledge on the compressive behaviour of bonded brickwork, a detailed numerical investigation has been reported in this paper. A simplified Finite element (FE) based micro-modelling technique was implemented to simulate the compression response of bonded brickwork specimens. The developed FE modelling technique was initially verified against the experimental predictions of compressive capacities and axial stress-strain curves. The numerical modelling results iterated that there was no noticeable increase in the compressive capacity of the masonry with increase in the brickwork thicknesses due to increased number of weak head joints. The validated models were then employed to study the effect of slenderness of the bonded brickwork specimens on the axial compression response. The height to thickness (slenderness) ratios of the bonded brickwork were varied from 1.4 to 10.9 for analysing 30 different cases with two brick strengths. Results showed that with increasing slenderness ratio, the compressive strength of the bonded brickwork reduces for all bonded thicknesses. The parametric study indicates that the slenderness ratio influences the compression characteristics of bonded brickwork specimens; subsequently, correction factors for the compressive strengths determined with different slenderness ratios of brickwo

В статье представлен подход к градостроительству и процессу урбанизации на основе математических моделей. Разработаны поправочные коэффициенты для определения арендной платы квартир. В работе предложен подход, основанный на использовании математической модели, которая позволяет выполнить калибровку параметров функции аренды при отсутствии данных о средней стоимости. Поправочные коэффициенты были найдены в результате решения задачи многокритериальной оптимизации. Рассмотрена связь математической модели Х.Хойта и социальной сферы в городах., The article presents an approach to urban planning and the process of urbanization based on mathematical models. Correction factors have been developed to determine the rent of apartments. The paper proposes an approach based on the use of a mathematical model that allows you to calibrate the parameters of the rental function in the absence of data on the average cost. Correction factors were found asa result of solving the problem of multicriteria optimization. The relationship between the mathematical model of H. Hoyt and the social sphere in cities is considered.

Forensic casework from past‐conflicts relies on the corrected historical Trotter data for stature estimation in Fordisc. For roughly 10 years’, stature estimation using this data has produced point estimates for the tibia that are on average 1.25 inches less than the other long bones. This issue was identified after applying the equations derived from Fordisc to the USS Oklahoma commingled assemblage. Reevaluation of Fordisc revealed that a correction factor of 20 mm, instead of 10 mm, was mistakenly applied to the Trotter tibia data. Historical forensic anthropology reports written at the Defense POW/MIA Accounting Agency were utilized to identify that the overcorrection is isolated to Fordisc 3 with an error rate of 5% of known antemortem statures falling outside of the prediction intervals that relied on the tibia. Further evaluation of the Oklahoma sample indicates the 10 mm correction is still producing point estimates less than the other long bones.

A method is presented for calculating the expected number of counts in peaks that have a large relative peak area uncertainty and appear in measured gamma-ray spectra. The method was applied to calculations of the correction factors for peaks occurring in the spectra of radon daughters. It was shown that the factors used for correcting the calculated peak areas to their expected values decrease with an increasing relative peak-area uncertainty. The accuracy of taking the systematic influence inducing the correction factors into account is given by the dispersion of the correction factors corresponding to specific peaks. It was shown that the highest accuracy is obtained in the peak analyses with the GammaVision and Gamma-W software.

A method is presented for calculating the expected number of counts in peaks that have a large relative peak area uncertainty and appear in measured gamma-ray spectra. The method was applied to calculations of the correction factors for peaks occurring in the spectra of radon daughters. It was shown that the factors used for correcting the calculated peak areas to their expected values decrease with an increasing relative peak-area uncertainty. The accuracy of taking the systematic influence inducing the correction factors into account is given by the dispersion of the correction factors corresponding to specific peaks. It was shown that the highest accuracy is obtained in the peak analyses with the GammaVision and Gamma-W software.

A method is presented for calculating the expected number of counts in peaks that have a large relative peak-area uncertainty and appear in measured gamma-ray spectra. The method was applied to calculations of the correction factors for peaks occurring in the spectra of radon daughters. It was shown that the factors used for correcting the calculated peak areas to their expected values decrease with an increasing relative peak-area uncertainty. The accuracy of taking the systematic influence inducing the correction factors into account is given by the dispersion of the correction factors corresponding to specific peaks. It was shown that the highest accuracy is obtained in the peak analyses with the GammaVision and Gamma-W software., Postprint (author's final draft)

BACKGROUND: Biomarkers of iron status are affected by inflammation. In order to interpret them in individuals with inflammation, the use of correction factors (CFs) has been proposed.OBJECTIVE: The objective of this study was to investigate the use of regression models as an alternative to the CF approach.METHODS: Morbidity data were collected during clinical examinations with morbidity recalls in a cross-sectional study in children aged 6-23 mo with moderate acute malnutrition. C-reactive protein (CRP), α1-acid glycoprotein (AGP), serum ferritin (SF), and soluble transferrin receptor (sTfR) were measured in serum. Generalized additive, quadratic, and linear models were used to model the relation between SF and sTfR as outcomes and CRP and AGP as categorical variables (model 1; equivalent to the CF approach), CRP and AGP as continuous variables (model 2), or CRP and AGP as continuous variables and morbidity covariates (model 3) as predictors. The predictive performance of the models was compared with the use of 10-fold crossvalidation and quantified with the use of root mean square errors (RMSEs). SF and sTfR were adjusted with the use of regression coefficients from linear models.RESULTS: Crossvalidation revealed no advantage to using generalized additive or quadratic models over linear models in terms of the RMSE. Linear model 3 performed better than models 2 and 1. Furthermore, we found no difference in CFs for adjusting SF and those from a previous meta-analysis. Adjustment of SF and sTfR with the use of the best-performing model led to a 17% point increase and <1% point decrease, respectively, in estimated prevalence of iron deficiency.CONCLUSION: Regression analysis is an alternative to adjust SF and may be preferable in research settings, because it can take morbidity and severity of inflammation into account. In clinical settings, the CF approach may be more practical. There is no benefit from adjusting sTfR. This trial was

Purpose The primary aim of this study was to determine correction factors, math formula for a PTW-31016 ionization chamber on field sizes from 0.5 cm × 0.5 cm to 2 cm × 2 cm for both flattened (FF) and flattened filter-free (FFF) beams produced in a TrueBeam clinical accelerator. The secondary objective was the determination of field output factors, math formula over this range of field sizes using both Monte Carlo (MC) simulation and measurements. Methods math formula for the PTW-31016 chamber were calculated by MC simulation for field sizes of 0.5 cm × 0.5 cm, 1 cm × 1 cm, and 2 cm × 2 cm. MC simulations were performed with the PENELOPE code system for the 10 MV FFF Particle Space File from a TrueBeam linear accelerator (LINAC) provided by the manufacturer (Varian Medical Systems, Inc. Palo Alto, CA, USA). Simulations were repeated taking into account chamber manufacturing tolerances and accelerator jaw positioning in order to assess the uncertainty of the calculated correction factors. Output ratios were measured on square fields ranging from 0.5 cm × 0.5 cm to 10 cm × 10 cm for 6 MV and 10 MV FF and FFF beams produced by a TrueBeam using a PTW-31016 ionization chamber; a Sun Nuclear Edge detector (SunNuclear Corp., Melbourne, FL, USA) and TLD–700R (Harshaw, Thermo Scientific, Waltham, MA, USA). The validity of the proposed correction factors was verified using the calculated correction factors for the determination of math formula using a PTW-31016 at the four TrueBeam energies and comparing the results with both TLD-700R measurements and MC simulations. Finally, the proposed correction factors were used to assess the correction factors of the SunNuclear Edge detector. Results The present work provides a set of MC calculated correction factors for a PTW-31016 chamber used on a TrueBeam FF and FFF mode. For the 0.5 cm × 0.5 cm square field size, math formula is equal to 1.17 with a combined uncertainty of 2% (k = 1). A detailed analysis of the most influential pa, Postprint (author's final draft)

Measurement errors in dietary assessment using duplicate portions as reference method Laura Trijsburg Background: As Food Frequency Questionnaires (FFQs) are subject to measurement error, associations between self-reported intake by FFQ and outcome measures should be corrected for measurement error with data from a reference method. Whether the correction is adequate depends on the characteristics of the reference method used in the validation study. The duplicate portion method (DP), compared to the often used 24h recall (24hR), seems a promising reference method as correlated errors between FFQ and DP, such as memory bias, errors in portion size estimations and food composition databases, are not expected. Aim: This thesis aimed to determine the validity of the DP compared to the 24hR as a reference method for FFQ validation. The second aim was to explore the validity of nutrient densities for DP, 24hR and FFQ. The third aim was to determine the factors associated with misreporting of energy, protein and potassium as estimated by DP, 24hR and FFQ. Methods: Within the DuPLO-study, a Dutch validation study which is part of the NQplus study, two DPs, two FFQs, two blood and urinary biomarkers and one to fifteen 24hRs (web-based and/or telephone-based) were collected in 198 subjects, within 1.5 years. Also, one or two doubly labelled water measurements were available for 69 participants. Multivariate measurement error models were used to assess proportional scaling bias, error correlations with the FFQ, validity coefficients and attenuation factors. Furthermore linear regression analysis was used to determine the association between misreporting and various factors. Results: The DP was less influenced by proportional scaling bias, had lower correlated errors with the FFQ and showed higher attenuation factors than the 24hR for potassium, sodium and protein. Also, the DP seemed a better reference method than the 24hR for the assessment of validity coefficients for the F

This study explores what difference, if any, the bias in self-reported body mass index (BMI) has on our understanding of the relationship between body size and income attainment. To accomplish this, aggregated data from Cycle 1 and Cycle 2 of the Canada Health Measures Survey, in which information on both self-reported and measured BMI was collected, are used. Based on subsamples of female and male employees, OLS regression analyses contrasting the effect of self-reported and measured BMI on income show that for women, self-reported BMI leads to underestimates of a negative body size effect, whereas for men, self-reported BMI leads to overestimates of a positive body size effect. Additional analyses examining the appropriateness of correction factors to improve the accuracy of self-reported BMI effect estimates suggest correction factors do little to reduce these systematic errors.

This study explores what difference, if any, the bias in self-reported body mass index (BMI) has on our understanding of the relationship between body size and income attainment. To accomplish this, aggregated data from Cycle 1 and Cycle 2 of the Canada Health Measures Survey, in which information on both self-reported and measured BMI was collected, are used. Based on subsamples of female and male employees, OLS regression analyses contrasting the effect of self-reported and measured BMI on income show that for women, self-reported BMI leads to underestimates of a negative body size effect, whereas for men, self-reported BMI leads to overestimates of a positive body size effect. Additional analyses examining the appropriateness of correction factors to improve the accuracy of self-reported BMI effect estimates suggest correction factors do little to reduce these systematic errors.

In Swedish practice, there is a long tradition of evaluating undrained shear strength from fall-cone tests and field vane tests. During the last 20 years cone penetration tests have also become widely used. However, the results from all these test methods have to be evaluated using empirical factors. The factors generally used for Swedish clays are related to liquid limit and overconsolidation, but they are not applicable to all types of fine-grained soils and can often be improved by local calibration for the particular type of soil in the area of current interest. For this calibration, the results of direct simple shear tests and/or triaxial tests in the laboratory are normally used. This paper presents an evaluation for Swedish fine-grained sulphide soils, for which a general correction factor of 0.65 for field vane tests and fall-cone tests, a cone factor Nkt of 20.2 for cone penetration tests and a relation cu,DSS/(σ′cOCR−0.2) of 0.28 have been found. No correlations were found between these empirical factors and the clay content, liquid limit or organic content, but a relationship was found between the overconsolidation ratio and both the cone penetration test and the field vane test. The sulphide soils in question are found in northern Sweden along the coast of the Gulf of Bothnia. They aremostly classified as organic silt or organic clay,which is normally silty., QC 20150313

This study explores what difference, if any, the bias in self-reported body mass index (BMI) has on our understanding of the relationship between body size and income attainment. To accomplish this, aggregated data from Cycle 1 and Cycle 2 of the Canada Health Measures Survey, in which information on both self-reported and measured BMI was collected, are used. Based on subsamples of female and male employees, OLS regression analyses contrasting the effect of self-reported and measured BMI on income show that for women, self-reported BMI leads to underestimates of a negative body size effect, whereas for men, self-reported BMI leads to overestimates of a positive body size effect. Additional analyses examining the appropriateness of correction factors to improve the accuracy of self-reported BMI effect estimates suggest correction factors do little to reduce these systematic errors.

This study explores what difference, if any, the bias in self-reported body mass index (BMI) has on our understanding of the relationship between body size and income attainment. To accomplish this, aggregated data from Cycle 1 and Cycle 2 of the Canada Health Measures Survey, in which information on both self-reported and measured BMI was collected, are used. Based on subsamples of female and male employees, OLS regression analyses contrasting the effect of self-reported and measured BMI on income show that for women, self-reported BMI leads to underestimates of a negative body size effect, whereas for men, self-reported BMI leads to overestimates of a positive body size effect. Additional analyses examining the appropriateness of correction factors to improve the accuracy of self-reported BMI effect estimates suggest correction factors do little to reduce these systematic errors.

This study explores what difference, if any, the bias in self-reported body mass index (BMI) has on our understanding of the relationship between body size and income attainment. To accomplish this, aggregated data from Cycle 1 and Cycle 2 of the Canada Health Measures Survey, in which information on both self-reported and measured BMI was collected, are used. Based on subsamples of female and male employees, OLS regression analyses contrasting the effect of self-reported and measured BMI on income show that for women, self-reported BMI leads to underestimates of a negative body size effect, whereas for men, self-reported BMI leads to overestimates of a positive body size effect. Additional analyses examining the appropriateness of correction factors to improve the accuracy of self-reported BMI effect estimates suggest correction factors do little to reduce these systematic errors.

A challenge of the past few decades for the Solar Observing Optical Network (SOON), operated by the United States Air Force Weather Agency (AFWA), has been to obtain consistent flare brightness reporting for the same flare from different sites. Flare area is usually considered to be a more reliable measure, but significant variation of values between sites still occurs. The Global Oscillation Network Group (GONG) deployed a Hα patrol system in 2010. This provides a modern system with near identical equipment to compare flares from six different sites. The classification of flares and techniques of flare measurement will be briefly discussed. The results presented here suggest that even though different GONG sites report different flare areas and brightness, for some sites they vary in a consistent way allowing correction factors to be applied.

The proposed revisions to the ANSI Z136, ICNIRP, and IEC 60825-1 laser exposure limits for multiple pulse ocular exposure for wavelengths from 400 to 1400 nm are examined for pulse durations t(sub p) /= t(sub min) (T[sub i]). The three rules that are defined to be applied for multiple pulse exposures (or for classification for IEC 60825-1) are compared to identify criteria for which one of the rules is the critical one, i.e., the rule that limits the energy per pulse for a given exposure or product emission. Such a comparison can help to simplify a safety analysis, but also guide the design of systems for which the output is to be maximized yet still be classified as a Class 1 or Class 2 laser system., Published in the Journal of Laser Applications, v25 n4, Aug 2013. Prepared in collaboration with Seibersdorf Laboratories, Test House for Laser, LED and Lamp Safety, Seibersdorf, Austria.

The concept of grid inefficiency in Frisch grid ionization chambers and its influence on the anode pulse shape is explained in terms of the ShockleyRamo theorem for induced charges. The grid inefficiency correction is deduced from numerically calculated weighting potentials. A method to determine the correction factor experimentally is also presented. Experimental and calculated values of the correction factor are shown to be in good agreement. © 2011 Elsevier B.V. All rights reserved., Cited By :32; Export Date: 16 December 2020; Article; CODEN: NIMAE; Correspondence Address: Göök, A.; Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany; email: agook@ikp.tu-darmstadt.de, QC 20201216

De lysimeters van PWN in de duinen van Castricum hebben in de vorige eeuw grote bekendheid gekregen. De wetenschappelijke vraagstelling van de invloed van begroeiing op de aanvulling van het onderliggende grondwater stond in het centrum van de hydrologische belangstelling. Vooral in de periode 1941 - 1972 was niets teveel om zoveel mogelijk gegevens te verzamelen. Piet van der Hoeven heeft in de jaren negentig zich beijverd de archieven voor een ieder beschikbaar te krijgen. Middels deze serie rapporten doet hij verslag van zijn resultaten. Nadat de invoer van de belangrijkste gegevens aan kant was en daar tevens de jacht op fouten eroverheen gegaan was, was duidelijk dat de bestanden daarmee nog geenszins volledig homogeen behoefden te zijn. Het verwijderen van die inhomogeniteiten is het onderwerp van dit rapport.

In the present study classical induction design tools are applied to the problem of heating non-magnetic metal billets, using 50 Hz AC. As an example of great practical industrial interest, the induction heating of aluminum billets is addressed specifically. The predicted work piece power is compared with the measured work piece power for a long and a short coil, using well established methods, such as those of Burch and Davis, introduced in 1926/28, Dwight and Bagai in 1935, Baker in 1944/57, Vaughan and Williamson in 1945, and by Tudbury in 1960. A calculation methodology based on a combination of the available tools is also introduced and discussed. The method has proven to give an error of <10% of the actual work piece power. An equation for Tudbury's work piece shortness correction factor is disclosed for the first time., QC 20140829

The area ratio method of Sjostrand is generally considered one of the most reliable reactivity determination methods and thus is a major candidate for off-line calibration purposes in future accelerator-driven systems for high-level waste incineration. In this work, the Sjostrand area ratio method has been evaluated experimentally under thorough conditions in the strongly heterogeneous subcritical facility YALINA-Booster. Both strengths and weaknesses of the method have been identified. Most surprisingly, it has been found that the area ratio reactivity estimates may differ a factor of 2 depending on detector position. It is also shown that this strong spatial dependence can be explained based on a simple two-region point-kinetics model and corrected by means of correction factors obtained through Monte Carlo simulations. A new Monte Carlo correction method is proposed that includes, at the same time, the spatial disturbance and the effective delayed neutron fraction. In that way, the value of the effective multiplication factor is obtained from the measured dollar reactivity without the need of calculating the effective delayed neutron fraction explicitly, and thereby, the delayed neutron transport is performed only once. Further, it has been found that the Sjostrand area ratio method is not sensitive to perturbations of the source multiplication factor., QC 20100621. Uppdaterad från accepted till published (20101203).

Voor het ontwerpen en toetsen van watersystemen maken waterbeheerders vaak gebruik van een statistiek van neerslagextremen, die gebaseerd is op een meetreeks van het KNMI-station De Bilt. Een recent uitgebreid onderzoek heeft tot nieuwe inzichten geleid over de grootte van plaatselijke verschillen binnen Nederland. Voor een aantal regio’s wordt aanbevolen de getallen voor De Bilt te corrigeren. Op een kaart van Nederland wordt de grootte van de correctiefactor weergegeven

In support of an online reactivity monitoring experiment, also presented in this conference, this work presents the reactivity calibration measurements performed with a pulsed neutron source in the coupled fast-thermal subcritical facility YALINA-Booster. These experiments reveal the complexity of experimentally obtaining a global reactivity from a highly heterogeneous core. Moreover, the effect of varying the source multiplication at constant reactivity on the area ratio technique is explored. It is found that the reactivity obtained with the area ratio technique carry strong spatial dependence, but it can be handled by calculated correction factors. On the other hand the method is showed not to be sensitive to changes in the source multiplication. It is also shown that the prompt neutron decay constant does not vary strongly over the core except at deep subcritical states., QC 20141009

Traditionally, heat losses from the turbine are neglected in turbomatching calculations as well as in engine simulations [1]. On the SI-engine, with it's high exhaust temperatures, this assumption will lead to errors in the calculations. Significant amounts of heat are dissipated from the turbine through several mechanisms. This paper contains measurements of the different heat loss mechanisms from the turbine during full load operation on a 4-cylinder SI-engine. The largest loss components are convective and radiative. The heat losses to cooling water and lubrication oil were approximately 3-5% of the total heat loss from the turbine. In addition to heat losses to the surroundings, heat flux is also present internally in the turbocharger. Heat flux from the turbine to the compressor can deteriorate the efficiency of the compressor. Measurements and calculations were performed for several heat flux conditions and it could be concluded that little possibility exists for significant heat flux through the rotor, instead the major heat flux comes from conduction in the housings and external radiation. With the heat transfer included in the model the turbine outlet temperature could be simulated very close to measured. However, incorporation of the heat losses in the simulation did not do very much for the necessity of using correction factors for the turbine efficiency., QC 20141210

Finite element calculations are performed to determine the effect of specimen aspect ratio (specimen height (h) divided by specimen width (w)) on the specimen geometry stress intensity correction factor (F = square roots of JE/(sigma square roots of pi alpha)) (where J is the J -integral, E is Young's modulus, sigma is the remote force divided by the uncracked area, and alpha is the crack length). F is a function of specimen geometry, and modifies the value of the Mode 1 stress intensity (K1). Linear elastic fracture mechanics (LEFM) and plane stress are assumed. Two specimen types are simulated, center cracked tension (CCT), and single edge notched tension (SENT). Two boundary conditions are simulated, prescribed uniform load, and prescribed uniform displacement. For each of the four combinations of specimen type and boundary condition, an estimate is made of the minimum value of h/w for which the effect on F can be neglected, in which case F can be calculated using an equation instead of from a numerical analysis.

Coyote (Canis latrans) food habits were detennined from 490 scats collected from October 1994 to October 1995 at DeSoto National Wildlife Refuge (DNWR), along the Nebraska/Iowa border. Mammals occurred most frequently, as measured by percent-of-scats (POS) , followed by vegetation, birds, and invertebrates. Mammals also constituted the largest portion of coyote diet, as determined by fresh weight correction factors. Within the mammalian category, white-tailed deer (Odocoileus virginianus) occurred most frequently and constituted the largest portion of diet by fresh weight correction factors. White-tailed deer occurrence and importance in diet peaked in June, which corresponds to the fawning period of white-tailed deer at DNWR. Mammals occurred in greater than 75 POS in all months except July and August, when mammals occurred in 38 and 30 POS, respectively. In July and August, vegetation in coyote scats, primarily mulberries (Morus spp.), was highest at 88 and 83 POS, respectively. Invertebrate occurrence peaked in May and in September. Bird occurrence peaked in December, which corresponded with the snow goose (Chen caerulescens) migration, and May, which corresponded with the nesting period for several species of ground nesting birds.