IRIS: Towards an Accurate and Fast Stage Weight Prediction Method
NASA Astrophysics Data System (ADS)
Taponier, V.; Balu, A.
2002-01-01
The knowledge of the structural mass fraction (or the mass ratio) of a given stage, which affects the performance of a rocket, is essential for the analysis of new or upgraded launchers or stages, whose need is increased by the quick evolution of the space programs and by the necessity of their adaptation to the market needs. The availability of this highly scattered variable, ranging between 0.05 and 0.15, is of primary importance at the early steps of the preliminary design studies. At the start of the staging and performance studies, the lack of frozen weight data (to be obtained later on from propulsion, trajectory and sizing studies) leads to rely on rough estimates, generally derived from printed sources and adapted. When needed, a consolidation can be acquired trough a specific analysis activity involving several techniques and implying additional effort and time. The present empirical approach allows thus to get approximated values (i.e. not necessarily accurate or consistent), inducing some result inaccuracy as well as, consequently, difficulties of performance ranking for a multiple option analysis, and an increase of the processing duration. This forms a classical harsh fact of the preliminary design system studies, insufficiently discussed to date. It appears therefore highly desirable to have, for all the evaluation activities, a reliable, fast and easy-to-use weight or mass fraction prediction method. Additionally, the latter should allow for a pre selection of the alternative preliminary configurations, making possible a global system approach. For that purpose, an attempt at modeling has been undertaken, whose objective was the determination of a parametric formulation of the mass fraction, to be expressed from a limited number of parameters available at the early steps of the project. It is based on the innovative use of a statistical method applicable to a variable as a function of several independent parameters. A specific polynomial generator
Code of Federal Regulations, 2010 CFR
2010-01-01
... by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (These... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Scale requirements for accurate... PROCEDURES AND REQUIREMENTS FOR ACCURATE WEIGHTS § 442.3 Scale requirements for accurate weights,...
Code of Federal Regulations, 2013 CFR
2013-01-01
... by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (These... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Scale requirements for accurate... PROCEDURES AND REQUIREMENTS FOR ACCURATE WEIGHTS § 442.3 Scale requirements for accurate weights,...
Code of Federal Regulations, 2014 CFR
2014-01-01
... by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (These... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Scale requirements for accurate... PROCEDURES AND REQUIREMENTS FOR ACCURATE WEIGHTS § 442.3 Scale requirements for accurate weights,...
Code of Federal Regulations, 2012 CFR
2012-01-01
... by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (These... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Scale requirements for accurate... PROCEDURES AND REQUIREMENTS FOR ACCURATE WEIGHTS § 442.3 Scale requirements for accurate weights,...
Code of Federal Regulations, 2011 CFR
2011-01-01
... by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (These... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Scale requirements for accurate... PROCEDURES AND REQUIREMENTS FOR ACCURATE WEIGHTS § 442.3 Scale requirements for accurate weights,...
Accurate measure by weight of liquids in industry
Muller, M.R.
1992-12-12
This research's focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.
Accurate measure by weight of liquids in industry. Final report
Muller, M.R.
1992-12-12
This research`s focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.
Efficient and Accurate WLAN Positioning with Weighted Graphs
NASA Astrophysics Data System (ADS)
Hansen, René; Thomsen, Bent
This paper concerns indoor location determination by using existing WLAN infrastructures and WLAN enabled mobile devices. The location fingerprinting technique performs localization by first constructing a radio map of signal strengths from nearby access points. The radio map is subsequently searched using a classification algorithm to determine a location estimate. This paper addresses two distinct challenges of location fingerprinting incurred by positioning moving users. Firstly, movement affects the positioning accuracy negatively due to increased signal strength fluctuations. Secondly, tracking moving users requires a low-latency overhead which translates into efficient computations to be done on a mobile device with limited capabilities. We present a technique to simultaneously improve the positioning accuracy and computational efficiency. The technique utilizes a weighted graph model of the indoor environment to improve positioning accuracy and computational efficiency by only considering the subset of locations in the radio map that are feasible to reach from a previously estimated position. The technique is general and can be used on top of any existing location system. Our results indicate that we are able to achieve similar dynamic localization accuracy to static localization. Effectively, we are able to counter the adverse effects of added signal fluctuations caused by movement. However, as some of our experiments testify, any location system is fundamentally constrained by the underlying environment. We give pointers to research which allows such problems to be detected early and thereby avoided before deploying a system.
9 CFR 201.71 - Scales; accurate weights, repairs, adjustments or replacements after inspection.
Code of Federal Regulations, 2014 CFR
2014-01-01
... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Scales; accurate weights, repairs... AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.71 Scales; accurate...
9 CFR 201.71 - Scales; accurate weights, repairs, adjustments or replacements after inspection.
Code of Federal Regulations, 2012 CFR
2012-01-01
... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Scales; accurate weights, repairs... AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.71 Scales; accurate...
9 CFR 201.71 - Scales; accurate weights, repairs, adjustments or replacements after inspection.
Code of Federal Regulations, 2013 CFR
2013-01-01
... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Scales; accurate weights, repairs... AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.71 Scales; accurate...
9 CFR 201.71 - Scales; accurate weights, repairs, adjustments or replacements after inspection.
Code of Federal Regulations, 2010 CFR
2010-01-01
... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Scales; accurate weights, repairs... AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.71 Scales; accurate...
9 CFR 201.71 - Scales; accurate weights, repairs, adjustments or replacements after inspection.
Code of Federal Regulations, 2011 CFR
2011-01-01
... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Scales; accurate weights, repairs... AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT Services § 201.71 Scales; accurate...
A live weight-heart girth relationship for accurate dosing of east African shorthorn zebu cattle.
Lesosky, Maia; Dumas, Sarah; Conradie, Ilana; Handel, Ian Graham; Jennings, Amy; Thumbi, Samuel; Toye, Phillip; Bronsvoort, Barend Mark de Clare
2013-01-01
The accurate estimation of livestock weights is important for many aspects of livestock management including nutrition, production and appropriate dosing of pharmaceuticals. Subtherapeutic dosing has been shown to accelerate pathogen resistance which can have subsequent widespread impacts. There are a number of published models for the prediction of live weight from morphometric measurements of cattle, but many of these models use measurements difficult to gather and include complicated age, size and gender stratification. In this paper, we use data from the Infectious Diseases of East Africa calf cohort study and additional data collected at local markets in western Kenya to develop a simple model based on heart girth circumference to predict live weight of east African shorthorn zebu (SHZ) cattle. SHZ cattle are widespread throughout eastern and southern Africa and are economically important multipurpose animals. We demonstrate model accuracy by splitting the data into training and validation subsets and comparing fitted and predicted values. The final model is weight(0.262) = 0.95 + 0.022 × girth which has an R (2) value of 0.98 and 95 % prediction intervals that fall within the ± 20 % body weight error band regarded as acceptable when dosing livestock. This model provides a highly reliable and accurate method for predicting weights of SHZ cattle using a single heart girth measurement which can be easily obtained with a tape measure in the field setting. PMID:22923040
NASA Astrophysics Data System (ADS)
Rhee, Young Min
2000-10-01
A modified method to construct an accurate potential energy surface by interpolation is presented. The modification is based on the use of Cartesian coordinates in the weighting function. The translational and rotational invariance of the potential is incorporated by a proper definition of the distance between two Cartesian configurations. A numerical algorithm to find the distance is developed. It is shown that the present method is more exact in describing a planar system compared to the previous methods with weightings in internal coordinates. The applicability of the method to reactive systems is also demonstrated by performing classical trajectory simulations on the surface.
Accurate response surface approximations for weight equations based on structural optimization
NASA Astrophysics Data System (ADS)
Papila, Melih
Accurate weight prediction methods are vitally important for aircraft design optimization. Therefore, designers seek weight prediction techniques with low computational cost and high accuracy, and usually require a compromise between the two. The compromise can be achieved by combining stress analysis and response surface (RS) methodology. While stress analysis provides accurate weight information, RS techniques help to transmit effectively this information to the optimization procedure. The focus of this dissertation is structural weight equations in the form of RS approximations and their accuracy when fitted to results of structural optimizations that are based on finite element analyses. Use of RS methodology filters out the numerical noise in structural optimization results and provides a smooth weight function that can easily be used in gradient-based configuration optimization. In engineering applications RS approximations of low order polynomials are widely used, but the weight may not be modeled well by low-order polynomials, leading to bias errors. In addition, some structural optimization results may have high-amplitude errors (outliers) that may severely affect the accuracy of the weight equation. Statistical techniques associated with RS methodology are sought in order to deal with these two difficulties: (1) high-amplitude numerical noise (outliers) and (2) approximation model inadequacy. The investigation starts with reducing approximation error by identifying and repairing outliers. A potential reason for outliers in optimization results is premature convergence, and outliers of such nature may be corrected by employing different convergence settings. It is demonstrated that outlier repair can lead to accuracy improvements over the more standard approach of removing outliers. The adequacy of approximation is then studied by a modified lack-of-fit approach, and RS errors due to the approximation model are reduced by using higher order polynomials. In
Regularization Based Iterative Point Match Weighting for Accurate Rigid Transformation Estimation.
Liu, Yonghuai; De Dominicis, Luigi; Wei, Baogang; Chen, Liang; Martin, Ralph R
2015-09-01
Feature extraction and matching (FEM) for 3D shapes finds numerous applications in computer graphics and vision for object modeling, retrieval, morphing, and recognition. However, unavoidable incorrect matches lead to inaccurate estimation of the transformation relating different datasets. Inspired by AdaBoost, this paper proposes a novel iterative re-weighting method to tackle the challenging problem of evaluating point matches established by typical FEM methods. Weights are used to indicate the degree of belief that each point match is correct. Our method has three key steps: (i) estimation of the underlying transformation using weighted least squares, (ii) penalty parameter estimation via minimization of the weighted variance of the matching errors, and (iii) weight re-estimation taking into account both matching errors and information learnt in previous iterations. A comparative study, based on real shapes captured by two laser scanners, shows that the proposed method outperforms four other state-of-the-art methods in terms of evaluating point matches between overlapping shapes established by two typical FEM methods, resulting in more accurate estimates of the underlying transformation. This improved transformation can be used to better initialize the iterative closest point algorithm and its variants, making 3D shape registration more likely to succeed. PMID:26357287
Ultrasound Fetal Weight Estimation: How Accurate Are We Now Under Emergency Conditions?
Dimassi, Kaouther; Douik, Fatma; Ajroudi, Mariem; Triki, Amel; Gara, Mohamed Faouzi
2015-10-01
The primary aim of this study was to evaluate the accuracy of sonographic estimation of fetal weight when performed at due date by first-line sonographers. This was a prospective study including 500 singleton pregnancies. Ultrasound examinations were performed by residents on delivery day. Estimated fetal weights (EFWs) were calculated and compared with the corresponding birth weights. The median absolute difference between EFW and birth weight was 200 g (100-330). This difference was within ±10% in 75.2% of the cases. The median absolute percentage error was 5.53% (2.70%-10.03%). Linear regression analysis revealed a good correlation between EFW and birth weight (r = 0.79, p < 0.0001). According to Bland-Altman analysis, bias was -85.06 g (95% limits of agreement: -663.33 to 494.21). In conclusion, EFWs calculated by residents were as accurate as those calculated by experienced sonographers. Nevertheless, predictive performance remains limited, with a low sensitivity in the diagnosis of macrosomia. PMID:26164286
Generalized weighted ratio method for accurate turbidity measurement over a wide range.
Liu, Hongbo; Yang, Ping; Song, Hong; Guo, Yilu; Zhan, Shuyue; Huang, Hui; Wang, Hangzhou; Tao, Bangyi; Mu, Quanquan; Xu, Jing; Li, Dejun; Chen, Ying
2015-12-14
Turbidity measurement is important for water quality assessment, food safety, medicine, ocean monitoring, etc. In this paper, a method that accurately estimates the turbidity over a wide range is proposed, where the turbidity of the sample is represented as a weighted ratio of the scattered light intensities at a series of angles. An improvement in the accuracy is achieved by expanding the structure of the ratio function, thus adding more flexibility to the turbidity-intensity fitting. Experiments have been carried out with an 850 nm laser and a power meter fixed on a turntable to measure the light intensity at different angles. The results show that the relative estimation error of the proposed method is 0.58% on average for a four-angle intensity combination for all test samples with a turbidity ranging from 160 NTU to 4000 NTU. PMID:26699060
A Weight-Averaged Interpolation Method for Coupling Time-Accurate Rarefied and Continuum Flows
NASA Astrophysics Data System (ADS)
Diaz, Steven William
A novel approach to coupling rarefied and continuum flow regimes as a single, hybrid model is introduced. The method borrows from techniques used in the simulation of spray flows to interpolate Lagrangian point-particles onto an Eulerian grid in a weight-averaged sense. A brief overview of traditional methods for modeling both rarefied and continuum domains is given, and a review of the literature regarding rarefied/continuum flow coupling is presented. Details of the theoretical development of the method of weighted interpolation are then described. The method evaluates macroscopic properties at the nodes of a CFD grid via the weighted interpolation of all simulated molecules in a set surrounding the node. The weight factor applied to each simulated molecule is the inverse of the linear distance between it and the given node. During development, the method was applied to several preliminary cases, including supersonic flow over an airfoil, subsonic flow over tandem airfoils, and supersonic flow over a backward facing step; all at low Knudsen numbers. The main thrust of the research centered on the time-accurate expansion of a rocket plume into a near-vacuum. The method proves flexible enough to be used with various flow solvers, demonstrated by the use of Fluent as the continuum solver for the preliminary cases and a NASA-developed Large Eddy Simulation research code, WRLES, for the full lunar model. The method is applicable to a wide range of Mach numbers and is completely grid independent, allowing the rarefied and continuum solvers to be optimized for their respective domains without consideration of the other. The work presented demonstrates the validity, and flexibility of the method of weighted interpolation as a novel concept in the field of hybrid flow coupling. The method marks a significant divergence from current practices in the coupling of rarefied and continuum flow domains and offers a kernel on which to base an ongoing field of research. It has the
ERIC Educational Resources Information Center
Natale, Ruby; Uhlhorn, Susan B.; Lopez-Mitnik, Gabriela; Camejo, Stephanie; Englebert, Nicole; Delamater, Alan M.; Messiah, Sarah E.
2016-01-01
Background: One in four preschool-age children in the United States are currently overweight or obese. Previous studies have shown that caregivers of this age group often have difficulty accurately recognizing their child's weight status. The purpose of this study was to examine factors associated with accurate/inaccurate perception of child body…
NASA Astrophysics Data System (ADS)
Rensonnet, Gaëtan; Jacobs, Damien; Macq, Benoît.; Taquet, Maxime
2016-03-01
Diffusion-weighted magnetic resonance imaging (DW-MRI) is a powerful tool to probe the diffusion of water through tissues. Through the application of magnetic gradients of appropriate direction, intensity and duration constituting the acquisition parameters, information can be retrieved about the underlying microstructural organization of the brain. In this context, an important and open question is to determine an optimal sequence of such acquisition parameters for a specific purpose. The use of simulated DW-MRI data for a given microstructural configuration provides a convenient and efficient way to address this problem. We first present a novel hybrid method for the synthetic simulation of DW-MRI signals that combines analytic expressions in simple geometries such as spheres and cylinders and Monte Carlo (MC) simulations elsewhere. Our hybrid method remains valid for any acquisition parameters and provides identical levels of accuracy with a computational time that is 90% shorter than that required by MC simulations for commonly-encountered microstructural configurations. We apply our novel simulation technique to estimate the radius of axons under various noise levels with different acquisition protocols commonly used in the literature. The results of our comparison suggest that protocols favoring a large number of gradient intensities such as a Cube and Sphere (CUSP) imaging provide more accurate radius estimation than conventional single-shell HARDI acquisitions for an identical acquisition time.
Are In-Bed Electronic Weights Recorded in the Medical Record Accurate?
Gerl, Heather; Miko, Alexandra; Nelson, Mandy; Godaire, Lori
2016-01-01
This study found large discrepancies between in-bed weights recorded in the medical record and carefully obtained standing weights with a calibrated, electronic bedside scale. This discrepancy appears to be related to inadequate bed calibration before patient admission and having excessive linen, clothing, and/or equipment on the bed during weighing by caregivers. PMID:27522846
ERIC Educational Resources Information Center
Geller, Josie; Srikameswaran, Suja; Zaitsoff, Shannon L.; Cockell, Sarah J.; Poole, Gary D.
2003-01-01
Examined parents' awareness of their daughters' attitudes, beliefs, and feelings about their bodies. Sixty-six adolescent daughters completed an eating disorder scale, a body figure rating scale, and made ratings of their shape and weight. Greater discrepancies between parents' estimates of daughters' body esteem and daughters' self-reported body…
Flocke, N
2009-08-14
In this paper it is shown that shifted Jacobi polynomials G(n)(p,q,x) can be used in connection with the Gaussian quadrature modified moment technique to greatly enhance the accuracy of evaluation of Rys roots and weights used in Gaussian integral evaluation in quantum chemistry. A general four-term inhomogeneous recurrence relation is derived for the shifted Jacobi polynomial modified moments over the Rys weight function e(-Tx)/square root x. It is shown that for q=1/2 this general four-term inhomogeneous recurrence relation reduces to a three-term p-dependent inhomogeneous recurrence relation. Adjusting p to proper values depending on the Rys exponential parameter T, the method is capable of delivering highly accurate results for large number of roots and weights in the most difficult to treat intermediate T range. Examples are shown, and detailed formulas together with practical suggestions for their efficient implementation are also provided. PMID:19691378
NASA Astrophysics Data System (ADS)
Flocke, N.
2009-08-01
In this paper it is shown that shifted Jacobi polynomials Gn(p,q,x) can be used in connection with the Gaussian quadrature modified moment technique to greatly enhance the accuracy of evaluation of Rys roots and weights used in Gaussian integral evaluation in quantum chemistry. A general four-term inhomogeneous recurrence relation is derived for the shifted Jacobi polynomial modified moments over the Rys weight function e-Tx/√x . It is shown that for q =1/2 this general four-term inhomogeneous recurrence relation reduces to a three-term p-dependent inhomogeneous recurrence relation. Adjusting p to proper values depending on the Rys exponential parameter T, the method is capable of delivering highly accurate results for large number of roots and weights in the most difficult to treat intermediate T range. Examples are shown, and detailed formulas together with practical suggestions for their efficient implementation are also provided.
Burward-Hoy, J. M.; Geist, W. H.; Krick, M. S.; Mayo, D. R.
2004-01-01
Neutron multiplicity counting is a technique for the rapid, nondestructive measurement of plutonium mass in pure and impure materials. This technique is very powerful because it uses the measured coincidence count rates to determine the sample mass without requiring a set of representative standards for calibration. Interpreting measured singles, doubles, and triples count rates using the three-parameter standard point model accurately determines plutonium mass, neutron multiplication, and the ratio of ({alpha},n) to spontaneous-fission neutrons (alpha) for oxides of moderate mass. However, underlying standard point model assumptions - including constant neutron energy and constant multiplication throughout the sample - cause significant biases for the mass, multiplication, and alpha in measurements of metal and large, dense oxides.
Natale, Ruby; Uhlhorn, Susan B; Lopez-Mitnik, Gabriela; Camejo, Stephanie; Englebert, Nicole; Delamater, Alan M; Messiah, Sarah E
2016-04-01
Background One in four preschool-age children in the United States are currently overweight or obese. Previous studies have shown that caregivers of this age group often have difficulty accurately recognizing their child's weight status. The purpose of this study was to examine factors associated with accurate/inaccurate perception of child body mass index (BMI) among a multicultural sample of caregivers who were predominantly low-income and foreign-born.Methods A total of 980 caregivers (72% Hispanic, 71% born outside of the United States) of preschool-age children (N= 1,105) were asked if their child was normal weight, overweight, or obese. Answers were compared to actual child BMI percentile category via chi-square analysis. Logistic regression analysis was performed to assess predictors of accurate perception of child BMI percentile category.Results More than one third of preschoolers were either overweight (18.4%) or obese (16.5%). The majority (92%) of caregivers of an overweight/obese child inaccurately perceived that their child was in a normal BMI category. Overall, foreign-born caregivers were significantly less likely to accurately perceive their child's BMI percentile category versus U.S.-born caregivers (odds ratio [OR] = 0.65, 95% confidence interval [CI] = 0.48-0.88). Specifically, those born in South America (OR = 0.59, 95% CI = 0.36-0.98), Central America/Mexico (OR = 0.59, 95% CI = 0.41-0.85), and Caribbean Hispanic nations (OR = 0.54, 95% CI = 0.35-0.83) were significantly less likely to accurately perceive their child's BMI category versus U.S.-born caregivers.Conclusions The results of this study suggest that foreign-born caregivers of U.S. preschool-age overweight/obese children in particular do not accurately perceive their child's BMI status. Health care professionals serving foreign-born caregivers may consider additional culturally appropriate healthy weight counseling for these families. PMID:26304710
Zhang, Xinyue; Lourenco, Daniela; Aguilar, Ignacio; Legarra, Andres; Misztal, Ignacy
2016-01-01
former. Manhattan plots had higher resolution with 5 and 100 QTL. Using a common weight for a window of 20 SNP that sums or averages the SNP variance enhances accuracy of predicting GEBV and provides accurate estimation of marker effects. PMID:27594861
Zhang, Xinyue; Lourenco, Daniela; Aguilar, Ignacio; Legarra, Andres; Misztal, Ignacy
2016-01-01
. Manhattan plots had higher resolution with 5 and 100 QTL. Using a common weight for a window of 20 SNP that sums or averages the SNP variance enhances accuracy of predicting GEBV and provides accurate estimation of marker effects. PMID:27594861
Majaj, Najib J; Hong, Ha; Solomon, Ethan A; DiCarlo, James J
2015-09-30
database of images for evaluating object recognition performance. We used multielectrode arrays to characterize hundreds of neurons in the visual ventral stream of nonhuman primates and measured the object recognition performance of >100 human observers. Remarkably, we found that simple learned weighted sums of firing rates of neurons in monkey inferior temporal (IT) cortex accurately predicted human performance. Although previous work led us to expect that IT would outperform V4, we were surprised by the quantitative precision with which simple IT-based linking hypotheses accounted for human behavior. PMID:26424887
Hong, Ha; Solomon, Ethan A.; DiCarlo, James J.
2015-01-01
database of images for evaluating object recognition performance. We used multielectrode arrays to characterize hundreds of neurons in the visual ventral stream of nonhuman primates and measured the object recognition performance of >100 human observers. Remarkably, we found that simple learned weighted sums of firing rates of neurons in monkey inferior temporal (IT) cortex accurately predicted human performance. Although previous work led us to expect that IT would outperform V4, we were surprised by the quantitative precision with which simple IT-based linking hypotheses accounted for human behavior. PMID:26424887
NASA Astrophysics Data System (ADS)
Saslow, Wayne M.
2014-04-01
Three common approaches to F→=ma→ are: (1) as an exactly true definition of force F→ in terms of measured inertial mass m and measured acceleration a→; (2) as an exactly true axiom relating measured values of a→, F→ and m; and (3) as an imperfect but accurately true physical law relating measured a→ to measured F→, with m an experimentally determined, matter-dependent constant, in the spirit of the resistance R in Ohm's law. In the third case, the natural units are those of a→ and F→, where a→ is normally specified using distance and time as standard units, and F→ from a spring scale as a standard unit; thus mass units are derived from force, distance, and time units such as newtons, meters, and seconds. The present work develops the third approach when one includes a second physical law (again, imperfect but accurate)—that balance-scale weight W is proportional to m—and the fact that balance-scale measurements of relative weight are more accurate than those of absolute force. When distance and time also are more accurately measurable than absolute force, this second physical law permits a shift to standards of mass, distance, and time units, such as kilograms, meters, and seconds, with the unit of force—the newton—a derived unit. However, were force and distance more accurately measurable than time (e.g., time measured with an hourglass), this second physical law would permit a shift to standards of force, mass, and distance units such as newtons, kilograms, and meters, with the unit of time—the second—a derived unit. Therefore, the choice of the most accurate standard units depends both on what is most accurately measurable and on the accuracy of physical law.
NASA Astrophysics Data System (ADS)
Gang, Jin; Yiqi, Zhuang; Yue, Yin; Miao, Cui
2015-03-01
A novel digitally controlled automatic gain control (AGC) loop circuitry for the global navigation satellite system (GNSS) receiver chip is presented. The entire AGC loop contains a programmable gain amplifier (PGA), an AGC circuit and an analog-to-digital converter (ADC), which is implemented in a 0.18 μm complementary metal-oxide-semiconductor (CMOS) process and measured. A binary-weighted approach is proposed in the PGA to achieve wide dB-linear gain control with small gain error. With binary-weighted cascaded amplifiers for coarse gain control, and parallel binary-weighted trans-conductance amplifier array for fine gain control, the PGA can provide a 64 dB dynamic range from -4 to 60 dB in 1.14 dB gain steps with a less than 0.15 dB gain error. Based on the Gaussian noise statistic characteristic of the GNSS signal, a digital AGC circuit is also proposed with low area and fast settling. The feed-backward AGC loop occupies an area of 0.27 mm2 and settles within less than 165 μs while consuming an average current of 1.92 mA at 1.8 V.
Deshpande, Amol A; Madhavan, P; Deshpande, Girish R; Chandel, Ravi Kumar; Yarbagi, Kaviraj M; Joshi, Alok R; Moses Babu, J; Murali Krishna, R; Rao, I M
2016-01-01
Fondaparinux sodium is a synthetic low-molecular-weight heparin (LMWH). This medication is an anticoagulant or a blood thinner, prescribed for the treatment of pulmonary embolism and prevention and treatment of deep vein thrombosis. Its determination in the presence of related impurities was studied and validated by a novel ion-pair HPLC method. The separation of the drug and its degradation products was achieved with the polymer-based PLRPs column (250 mm × 4.6 mm; 5 μm) in gradient elution mode. The mixture of 100 mM n-hexylamine and 100 mM acetic acid in water was used as buffer solution. Mobile phase A and mobile phase B were prepared by mixing the buffer and acetonitrile in the ratio of 90:10 (v/v) and 20:80 (v/v), respectively. Mobile phases were delivered in isocratic mode (2% B for 0-5 min) followed by gradient mode (2-85% B in 5-60 min). An Evaporative Light Scattering Detector (ELSD) was connected to the LC system to detect the responses of chromatographic separation. Further, the drug was subjected to stress studies for acidic, basic, oxidative, photolytic, and thermal degradations as per ICH guidelines and the drug was found to be labile in acid, base hydrolysis, and oxidation, while stable in neutral, thermal, and photolytic degradation conditions. The method provided linear responses over the concentration range of the LOQ to 0.30% for each impurity with respect to the analyte concentration of 12.5 mg/mL, and regression analysis showed a correlation coefficient value (r(2)) of more than 0.99 for all the impurities. The LOD and LOQ were found to be 1.4 µg/mL and 4.1 µg/mL, respectively, for fondaparinux. The developed ion-pair method was validated as per ICH guidelines with respect to accuracy, selectivity, precision, linearity, and robustness. PMID:27110496
Deshpande, Amol A.; Madhavan, P.; Deshpande, Girish R.; Chandel, Ravi Kumar; Yarbagi, Kaviraj M.; Joshi, Alok R.; Moses Babu, J.; Murali Krishna, R.; Rao, I. M.
2016-01-01
Fondaparinux sodium is a synthetic low-molecular-weight heparin (LMWH). This medication is an anticoagulant or a blood thinner, prescribed for the treatment of pulmonary embolism and prevention and treatment of deep vein thrombosis. Its determination in the presence of related impurities was studied and validated by a novel ion-pair HPLC method. The separation of the drug and its degradation products was achieved with the polymer-based PLRPs column (250 mm × 4.6 mm; 5 μm) in gradient elution mode. The mixture of 100 mM n-hexylamine and 100 mM acetic acid in water was used as buffer solution. Mobile phase A and mobile phase B were prepared by mixing the buffer and acetonitrile in the ratio of 90:10 (v/v) and 20:80 (v/v), respectively. Mobile phases were delivered in isocratic mode (2% B for 0–5 min) followed by gradient mode (2–85% B in 5–60 min). An Evaporative Light Scattering Detector (ELSD) was connected to the LC system to detect the responses of chromatographic separation. Further, the drug was subjected to stress studies for acidic, basic, oxidative, photolytic, and thermal degradations as per ICH guidelines and the drug was found to be labile in acid, base hydrolysis, and oxidation, while stable in neutral, thermal, and photolytic degradation conditions. The method provided linear responses over the concentration range of the LOQ to 0.30% for each impurity with respect to the analyte concentration of 12.5 mg/mL, and regression analysis showed a correlation coefficient value (r2) of more than 0.99 for all the impurities. The LOD and LOQ were found to be 1.4 µg/mL and 4.1 µg/mL, respectively, for fondaparinux. The developed ion-pair method was validated as per ICH guidelines with respect to accuracy, selectivity, precision, linearity, and robustness. PMID:27110496
ERIC Educational Resources Information Center
Rom, Mark Carl
2011-01-01
Grades matter. College grading systems, however, are often ad hoc and prone to mistakes. This essay focuses on one factor that contributes to high-quality grading systems: grading accuracy (or "efficiency"). I proceed in several steps. First, I discuss the elements of "efficient" (i.e., accurate) grading. Next, I present analytical results…
NASA Technical Reports Server (NTRS)
Feiveson, A. H. (Principal Investigator)
1979-01-01
The use of a weighted aggregation technique to improve the precision of the overall LACIE estimate is considered. The manner in which a weighted aggregation technique is implemented given a set of weights is described. The problem of variance estimation is discussed and the question of how to obtain the weights in an operational environment is addressed.
Accurate monotone cubic interpolation
NASA Technical Reports Server (NTRS)
Huynh, Hung T.
1991-01-01
Monotone piecewise cubic interpolants are simple and effective. They are generally third-order accurate, except near strict local extrema where accuracy degenerates to second-order due to the monotonicity constraint. Algorithms for piecewise cubic interpolants, which preserve monotonicity as well as uniform third and fourth-order accuracy are presented. The gain of accuracy is obtained by relaxing the monotonicity constraint in a geometric framework in which the median function plays a crucial role.
Accurate Finite Difference Algorithms
NASA Technical Reports Server (NTRS)
Goodrich, John W.
1996-01-01
Two families of finite difference algorithms for computational aeroacoustics are presented and compared. All of the algorithms are single step explicit methods, they have the same order of accuracy in both space and time, with examples up to eleventh order, and they have multidimensional extensions. One of the algorithm families has spectral like high resolution. Propagation with high order and high resolution algorithms can produce accurate results after O(10(exp 6)) periods of propagation with eight grid points per wavelength.
... heart failure, and kidney disease. Good nutrition and exercise can help in losing weight. Eating extra calories within a well-balanced diet and treating any underlying medical problems can help to add weight.
... obese. Achieving a healthy weight can help you control your cholesterol, blood pressure and blood sugar. It ... use more calories than you eat. A weight-control strategy might include Choosing low-fat, low-calorie ...
... to medicines, thyroid problems, heart failure, and kidney disease. Good nutrition and exercise can help in losing weight. Eating extra calories within a well-balanced diet and treating any underlying medical problems can help to add weight.
NASA Astrophysics Data System (ADS)
Itano, Wayne M.; Ramsey, Norman F.
1993-07-01
The paper discusses current methods for accurate measurements of time by conventional atomic clocks, with particular attention given to the principles of operation of atomic-beam frequency standards, atomic hydrogen masers, and atomic fountain and to the potential use of strings of trapped mercury ions as a time device more stable than conventional atomic clocks. The areas of application of the ultraprecise and ultrastable time-measuring devices that tax the capacity of modern atomic clocks include radio astronomy and tests of relativity. The paper also discusses practical applications of ultraprecise clocks, such as navigation of space vehicles and pinpointing the exact position of ships and other objects on earth using the GPS.
Accurate quantum chemical calculations
NASA Technical Reports Server (NTRS)
Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.
1989-01-01
An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.
... Quit Smoking Benefits of Quitting Health Effects of Smoking Secondhand Smoke Withdrawal Ways to Quit QuitGuide Pregnancy & Motherhood Pregnancy & Motherhood Before Your Baby is Born From Birth to 2 Years Quitting for Two SmokefreeMom Healthy Kids Parenting & ... Weight Management Weight Management ...
NASA Technical Reports Server (NTRS)
Howard, W. H.; Young, D. R.
1972-01-01
Device applies compressive force to bone to minimize loss of bone calcium during weightlessness or bedrest. Force is applied through weights, or hydraulic, pneumatic or electrically actuated devices. Device is lightweight and easy to maintain and operate.
The Robust Weighted Multi-Objective Game
2015-01-01
This paper studies a class of multi-objective n-person non-zero sum games through a robust weighted approach where each player has more than one competing objective. This robust weighted multi-objective game model assumes that each player attaches a set of weights to its objectives instead of accessing accurate weights. Each player wishes to minimize its maximum weighted sum objective where the maximization is pointing to the set of weights. To address this new model, a new equilibrium concept-robust weighted Nash equilibrium is obtained. The existence of this new concept is proven on suitable assumptions about the multi-objective payoffs. PMID:26406986
NNLOPS accurate associated HW production
NASA Astrophysics Data System (ADS)
Astill, William; Bizon, Wojciech; Re, Emanuele; Zanderighi, Giulia
2016-06-01
We present a next-to-next-to-leading order accurate description of associated HW production consistently matched to a parton shower. The method is based on reweighting events obtained with the HW plus one jet NLO accurate calculation implemented in POWHEG, extended with the MiNLO procedure, to reproduce NNLO accurate Born distributions. Since the Born kinematics is more complex than the cases treated before, we use a parametrization of the Collins-Soper angles to reduce the number of variables required for the reweighting. We present phenomenological results at 13 TeV, with cuts suggested by the Higgs Cross section Working Group.
NASA Technical Reports Server (NTRS)
1995-01-01
The Attitude Adjuster is a system for weight repositioning corresponding to a SCUBA diver's changing positions. Compact tubes on the diver's air tank permit controlled movement of lead balls within the Adjuster, automatically repositioning when the diver changes position. Manufactured by Think Tank Technologies, the system is light and small, reducing drag and energy requirements and contributing to lower air consumption. The Mid-Continent Technology Transfer Center helped the company with both technical and business information and arranged for the testing at Marshall Space Flight Center's Weightlessness Environmental Training Facility for astronauts.
How to accurately bypass damage
Broyde, Suse; Patel, Dinshaw J.
2016-01-01
Ultraviolet radiation can cause cancer through DNA damage — specifically, by linking adjacent thymine bases. Crystal structures show how the enzyme DNA polymerase η accurately bypasses such lesions, offering protection. PMID:20577203
Accurate Evaluation of Quantum Integrals
NASA Technical Reports Server (NTRS)
Galant, David C.; Goorvitch, D.
1994-01-01
Combining an appropriate finite difference method with Richardson's extrapolation results in a simple, highly accurate numerical method for solving a Schr\\"{o}dinger's equation. Important results are that error estimates are provided, and that one can extrapolate expectation values rather than the wavefunctions to obtain highly accurate expectation values. We discuss the eigenvalues, the error growth in repeated Richardson's extrapolation, and show that the expectation values calculated on a crude mesh can be extrapolated to obtain expectation values of high accuracy.
[Controlled weight bearing after osteosynthesis].
Perren, T; Matter, P
1993-01-01
Patient compliance with postoperative partial weight bearing can be a difficult management problem. The problem may be intentional or unintentional. There is no objective way to assess the amount of weight placed on the lower extremity by the patient. It is our clinical suspicion that patients place more weight than is desirable on the effected limb. There are few reports in the literature on this topic. One study has confirmed our suspicion of poor patient compliance with postoperative weight bearing. Our goal is to develop a system to accurately assess weight bearing and to improve this aspect of postoperative fracture care. Through an active feedback device we hope to improve patient education and understanding. We plan to study the clinical applications of using a pressure sensitive shoe insert device. Our ultimate goal is to improve upon the present device and to study the clinical application of there use. PMID:8123330
Link Prediction in Weighted Networks: A Weighted Mutual Information Model
Zhu, Boyao; Xia, Yongxiang
2016-01-01
The link-prediction problem is an open issue in data mining and knowledge discovery, which attracts researchers from disparate scientific communities. A wealth of methods have been proposed to deal with this problem. Among these approaches, most are applied in unweighted networks, with only a few taking the weights of links into consideration. In this paper, we present a weighted model for undirected and weighted networks based on the mutual information of local network structures, where link weights are applied to further enhance the distinguishable extent of candidate links. Empirical experiments are conducted on four weighted networks, and results show that the proposed method can provide more accurate predictions than not only traditional unweighted indices but also typical weighted indices. Furthermore, some in-depth discussions on the effects of weak ties in link prediction as well as the potential to predict link weights are also given. This work may shed light on the design of algorithms for link prediction in weighted networks. PMID:26849659
Link Prediction in Weighted Networks: A Weighted Mutual Information Model.
Zhu, Boyao; Xia, Yongxiang
2016-01-01
The link-prediction problem is an open issue in data mining and knowledge discovery, which attracts researchers from disparate scientific communities. A wealth of methods have been proposed to deal with this problem. Among these approaches, most are applied in unweighted networks, with only a few taking the weights of links into consideration. In this paper, we present a weighted model for undirected and weighted networks based on the mutual information of local network structures, where link weights are applied to further enhance the distinguishable extent of candidate links. Empirical experiments are conducted on four weighted networks, and results show that the proposed method can provide more accurate predictions than not only traditional unweighted indices but also typical weighted indices. Furthermore, some in-depth discussions on the effects of weak ties in link prediction as well as the potential to predict link weights are also given. This work may shed light on the design of algorithms for link prediction in weighted networks. PMID:26849659
... loss-rapid weight loss; Overweight-rapid weight loss; Obesity-rapid weight loss; Diet-rapid weight loss ... for people who have health problems because of obesity. For these people, losing a lot of weight ...
Pregnancy Weight Gain Calculator
... Newsroom Dietary Guidelines Communicator’s Guide Pregnancy Weight Gain Calculator You are here Home / Online Tools Pregnancy Weight Gain Calculator Print Share Pregnancy Weight Gain Calculator Pregnancy Weight Gain Calculator Pregnancy Weight Gain Intro ...
Precise and Accurate Density Determination of Explosives Using Hydrostatic Weighing
B. Olinger
2005-07-01
Precise and accurate density determination requires weight measurements in air and water using sufficiently precise analytical balances, knowledge of the densities of air and water, knowledge of thermal expansions, availability of a density standard, and a method to estimate the time to achieve thermal equilibrium with water. Density distributions in pressed explosives are inferred from the densities of elements from a central slice.
Accurate radiative transfer calculations for layered media.
Selden, Adrian C
2016-07-01
Simple yet accurate results for radiative transfer in layered media with discontinuous refractive index are obtained by the method of K-integrals. These are certain weighted integrals applied to the angular intensity distribution at the refracting boundaries. The radiative intensity is expressed as the sum of the asymptotic angular intensity distribution valid in the depth of the scattering medium and a transient term valid near the boundary. Integrated boundary equations are obtained, yielding simple linear equations for the intensity coefficients, enabling the angular emission intensity and the diffuse reflectance (albedo) and transmittance of the scattering layer to be calculated without solving the radiative transfer equation directly. Examples are given of half-space, slab, interface, and double-layer calculations, and extensions to multilayer systems are indicated. The K-integral method is orders of magnitude more accurate than diffusion theory and can be applied to layered scattering media with a wide range of scattering albedos, with potential applications to biomedical and ocean optics. PMID:27409700
Accurate Prediction of Docked Protein Structure Similarity.
Akbal-Delibas, Bahar; Pomplun, Marc; Haspel, Nurit
2015-09-01
One of the major challenges for protein-protein docking methods is to accurately discriminate nativelike structures. The protein docking community agrees on the existence of a relationship between various favorable intermolecular interactions (e.g. Van der Waals, electrostatic, desolvation forces, etc.) and the similarity of a conformation to its native structure. Different docking algorithms often formulate this relationship as a weighted sum of selected terms and calibrate their weights against specific training data to evaluate and rank candidate structures. However, the exact form of this relationship is unknown and the accuracy of such methods is impaired by the pervasiveness of false positives. Unlike the conventional scoring functions, we propose a novel machine learning approach that not only ranks the candidate structures relative to each other but also indicates how similar each candidate is to the native conformation. We trained the AccuRMSD neural network with an extensive dataset using the back-propagation learning algorithm. Our method achieved predicting RMSDs of unbound docked complexes with 0.4Å error margin. PMID:26335807
Multi sensor transducer and weight factor
NASA Technical Reports Server (NTRS)
Immer, Christopher D. (Inventor); Lane, John (Inventor); Eckhoff, Anthony J. (Inventor); Perotti, Jose M. (Inventor)
2004-01-01
A multi-sensor transducer and processing method allow insitu monitoring of the senor accuracy and transducer `health`. In one embodiment, the transducer has multiple sensors to provide corresponding output signals in response to a stimulus, such as pressure. A processor applies individual weight factors to reach of the output signals and provide a single transducer output that reduces the contribution from inaccurate sensors. The weight factors can be updated and stored. The processor can use the weight factors to provide a `health` of the transducer based upon the number of accurate versus in-accurate sensors in the transducer.
Minimum variance beamformer weights revisited.
Moiseev, Alexander; Doesburg, Sam M; Grunau, Ruth E; Ribary, Urs
2015-10-15
Adaptive minimum variance beamformers are widely used analysis tools in MEG and EEG. When the target brain activity presents in the form of spatially localized responses, the procedure usually involves two steps. First, positions and orientations of the sources of interest are determined. Second, the filter weights are calculated and source time courses reconstructed. This last step is the object of the current study. Despite different approaches utilized at the source localization stage, basic expressions for the weights have the same form, dictated by the minimum variance condition. These classic expressions involve covariance matrix of the measured field, which includes contributions from both the sources of interest and the noise background. We show analytically that the same weights can alternatively be obtained, if the full field covariance is replaced with that of the noise, provided the beamformer points to the true sources precisely. In practice, however, a certain mismatch is always inevitable. We show that such mismatch results in partial suppression of the true sources if the traditional weights are used. To avoid this effect, the "alternative" weights based on properly estimated noise covariance should be applied at the second, source time course reconstruction step. We demonstrate mathematically and using simulated and real data that in many situations the alternative weights provide significantly better time course reconstruction quality than the traditional ones. In particular, they a) improve source-level SNR and yield more accurately reconstructed waveforms; b) provide more accurate estimates of inter-source correlations; and c) reduce the adverse influence of the source correlations on the performance of single-source beamformers, which are used most often. Importantly, the alternative weights come at no additional computational cost, as the structure of the expressions remains the same. PMID:26143207
Misperceptions of weight status among adolescents: sociodemographic and behavioral correlates
Bodde, Amy E; Beebe, Timothy J; Chen, Laura P; Jenkins, Sarah; Perez-Vergara, Kelly; Finney Rutten, Lila J; Ziegenfuss, Jeanette Y
2014-01-01
Objective Accurate perceptions of weight status are important motivational triggers for weight loss among overweight or obese individuals, yet weight misperception is prevalent. To identify and characterize individuals holding misperceptions around their weight status, it may be informative for clinicians to assess self-reported body mass index (BMI) classification (ie, underweight, normal, overweight, obese) in addition to clinical weight measurement. Methods Self-reported weight classification data from the 2007 Current Visit Information – Child and Adolescent Survey collected at Mayo Clinic in Rochester, MN, were compared with measured clinical height and weight for 2,993 adolescents. Results While, overall, 74.2% of adolescents accurately reported their weight status, females, younger adolescents, and proxy (vs self) reporters were more accurate. Controlling for demographic and behavioral characteristics, the higher an individual’s BMI percentile, the less likely there was agreement between self-report and measured BMI percentile. Those with high BMI who misperceive their weight status were less likely than accurate perceivers to attempt weight loss. Conclusion Adolescents’ and proxies’ misperception of weight status increases with BMI percentile. Obtaining an adolescent’s self-perceived weight status in addition to measured height and weight offers clinicians valuable baseline information to discuss motivation for weight loss. PMID:25525400
Lo, Wing-Sze; Ho, Sai-Yin; Mak, Kwok-Kei; Lai, Yuen-Kwan; Lam, Tai-Hing
2009-01-01
Background Weight comments are commonly received by adolescents, but the accuracy of the comments and their effects on weight misperception are unclear. We assessed the prevalence and accuracy of weight comments received by Chinese adolescents from different sources and their relation to weight misperception. Methods In the Hong Kong Student Obesity Surveillance (HKSOS) project 2006–07, 22612 students aged 11–18 (41.5% boys) completed a questionnaire on obesity. Students responded if family members, peers and professionals had seriously commented over the past 30 days that they were "too fat" or "too thin" in two separate questions. The accuracy of the comments was judged against the actual weight status derived from self-reported height and weight. Self-perceived weight status was also reported and any discordance with the actual weight status denoted weight misperception. Logistic regression yielded adjusted odd ratios for weight misperception by the type of weight comments received. Results One in three students received weight comments, and the mother was the most common source of weight comments. Health professional was the most accurate source of weight comments, yet less than half the comments were correct. Adolescents receiving incorrect comments had increased risk of having weight misperception in all weight status groups. Receiving conflicting comments was positively associated with weight misperception among normal weight adolescents. In contrast, underweight and overweight/obese adolescents receiving correct weight comments were less likely to have weight misperception. Conclusion Weight comments, mostly incorrect, were commonly received by Chinese adolescents in Hong Kong, and such incorrect comments were associated with weight misperception. PMID:19642972
Predict amine solution properties accurately
Cheng, S.; Meisen, A.; Chakma, A.
1996-02-01
Improved process design begins with using accurate physical property data. Especially in the preliminary design stage, physical property data such as density viscosity, thermal conductivity and specific heat can affect the overall performance of absorbers, heat exchangers, reboilers and pump. These properties can also influence temperature profiles in heat transfer equipment and thus control or affect the rate of amine breakdown. Aqueous-amine solution physical property data are available in graphical form. However, it is not convenient to use with computer-based calculations. Developed equations allow improved correlations of derived physical property estimates with published data. Expressions are given which can be used to estimate physical properties of methyldiethanolamine (MDEA), monoethanolamine (MEA) and diglycolamine (DGA) solutions.
Accurate thickness measurement of graphene
NASA Astrophysics Data System (ADS)
Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.
2016-03-01
Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.
African American Women's Perception of Their Own Weight Status Compared to Measured Weight Status
Technology Transfer Automated Retrieval System (TEKTRAN)
Previous research indicates that African American (AA) women may be more accepting of larger body sizes compared with women of other races. This study assessed whether AA women perceived their own weight status accurately, when compared with their actual weight classification. Participants were 528 ...
Effect of clothing weight on body weight
Technology Transfer Automated Retrieval System (TEKTRAN)
Background: In clinical settings, it is common to measure weight of clothed patients and estimate a correction for the weight of clothing, but we can find no papers in the medical literature regarding the variability in clothing weight with weather, season, and gender. Methods: Fifty adults (35 wom...
Informed Test Component Weighting.
ERIC Educational Resources Information Center
Rudner, Lawrence M.
2001-01-01
Identifies and evaluates alternative methods for weighting tests. Presents formulas for composite reliability and validity as a function of component weights and suggests a rational process that identifies and considers trade-offs in determining weights. Discusses drawbacks to implicit weighting and explicit weighting and the difficulty of…
Accurate ab Initio Spin Densities
2012-01-01
We present an approach for the calculation of spin density distributions for molecules that require very large active spaces for a qualitatively correct description of their electronic structure. Our approach is based on the density-matrix renormalization group (DMRG) algorithm to calculate the spin density matrix elements as a basic quantity for the spatially resolved spin density distribution. The spin density matrix elements are directly determined from the second-quantized elementary operators optimized by the DMRG algorithm. As an analytic convergence criterion for the spin density distribution, we employ our recently developed sampling-reconstruction scheme [J. Chem. Phys.2011, 134, 224101] to build an accurate complete-active-space configuration-interaction (CASCI) wave function from the optimized matrix product states. The spin density matrix elements can then also be determined as an expectation value employing the reconstructed wave function expansion. Furthermore, the explicit reconstruction of a CASCI-type wave function provides insight into chemically interesting features of the molecule under study such as the distribution of α and β electrons in terms of Slater determinants, CI coefficients, and natural orbitals. The methodology is applied to an iron nitrosyl complex which we have identified as a challenging system for standard approaches [J. Chem. Theory Comput.2011, 7, 2740]. PMID:22707921
Towards an accurate bioimpedance identification
NASA Astrophysics Data System (ADS)
Sanchez, B.; Louarroudi, E.; Bragos, R.; Pintelon, R.
2013-04-01
This paper describes the local polynomial method (LPM) for estimating the time-invariant bioimpedance frequency response function (FRF) considering both the output-error (OE) and the errors-in-variables (EIV) identification framework and compare it with the traditional cross— and autocorrelation spectral analysis techniques. The bioimpedance FRF is measured with the multisine electrical impedance spectroscopy (EIS) technique. To show the overwhelming accuracy of the LPM approach, both the LPM and the classical cross— and autocorrelation spectral analysis technique are evaluated through the same experimental data coming from a nonsteady-state measurement of time-varying in vivo myocardial tissue. The estimated error sources at the measurement frequencies due to noise, σnZ, and the stochastic nonlinear distortions, σZNL, have been converted to Ω and plotted over the bioimpedance spectrum for each framework. Ultimately, the impedance spectra have been fitted to a Cole impedance model using both an unweighted and a weighted complex nonlinear least square (CNLS) algorithm. A table is provided with the relative standard errors on the estimated parameters to reveal the importance of which system identification frameworks should be used.
... Measure and Interpret Weight Status Adult Body Mass Index or BMI Body Mass Index (BMI) is a person's weight in kilograms divided ... finding your height and weight in this BMI Index Chart 1 . If your BMI is less than ...
Body Weight Relationships in Early Marriage: Weight Relevance, Weight Comparisons, and Weight Talk
Bove, Caron F.; Sobal, Jeffery
2011-01-01
This investigation uncovered processes underlying the dynamics of body weight and body image among individuals involved in nascent heterosexual marital relationships in Upstate New York. In-depth, semi-structured qualitative interviews conducted with 34 informants, 20 women and 14 men, just prior to marriage and again one year later were used to explore continuity and change in cognitive, affective, and behavioral factors relating to body weight and body image at the time of marriage, an important transition in the life course. Three major conceptual themes operated in the process of developing and enacting informants’ body weight relationships with their partner: weight relevance, weight comparisons, and weight talk. Weight relevance encompassed the changing significance of weight during early marriage and included attracting and capturing a mate, relaxing about weight, living healthily, and concentrating on weight. Weight comparisons between partners involved weight relativism, weight competition, weight envy, and weight role models. Weight talk employed pragmatic talk, active and passive reassurance, and complaining and critiquing criticism. Concepts emerging from this investigation may be useful in designing future studies of and approaches to managing body weight in adulthood. PMID:21864601
Fact Sheet Proven Weight Loss Methods What can weight loss do for you? Losing weight can improve your health in a number of ways. It can lower ... at www.hormone.org/Spanish . Proven Weight Loss Methods Fact Sheet www.hormone.org
Weight loss surgery helps people with extreme obesity to lose weight. It may be an option if you cannot lose weight through diet and exercise or have serious health problems caused by obesity. There are different types of weight loss surgery. They often limit the ...
38 CFR 4.46 - Accurate measurement.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...
38 CFR 4.46 - Accurate measurement.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...
38 CFR 4.46 - Accurate measurement.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...
38 CFR 4.46 - Accurate measurement.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...
38 CFR 4.46 - Accurate measurement.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...
PREVENTING WEIGHT REGAIN AFTER WEIGHT LOSS
Technology Transfer Automated Retrieval System (TEKTRAN)
For most dieters, a regaining of lost weight is an all too common experience. Indeed, virtually all interventions for weight loss show limited or even poor long-term effectiveness. This sobering reality was reflected in a comprehensive review of nonsurgical treatments of obesity conducted by the Ins...
Lerner, Lorena; Hayes, Teresa G; Tao, Nianjun; Krieger, Brian; Feng, Bin; Wu, Zhenhua; Nicoletti, Richard; Chiu, M Isabel; Gyuris, Jeno; Garcia, Jose M
2015-01-01
Background Cancer-related weight loss is associated with increased inflammation and decreased survival. The novel inflammatory mediator growth differentiation factor (GDF)15 is associated with poor prognosis in cancer but its role in cancer-related weight loss (C-WL) remains unclear. Our objective was to measure GDF15 in plasma samples of cancer subjects and controls and establish its association with other inflammatory markers and clinical outcomes. Methods We measured body weight, appetite, plasma GDF15, and other inflammatory markers in men with cancer-related weight loss (C-WL, n = 58), weight stable patients with cancer (C-WS, n = 72), and non-cancer controls (Co, n = 59) matched by age and pre-illness body mass index. In a subset of patients we also measured handgrip strength, appendicular lean body mass (aLBM), Eastern Cooperative Oncology Group (ECOG), and Karnofsky performance scores. Results GDF15, interleukin (IL)-6 and IL-8 were increased in C-WL versus other groups. IL-1 receptor antagonist, IL-4, interferon–gamma, tumour necrosis factor alpha, and vascular endothelial growth factor A were increased in C-WL versus C-WS, and Activin A was significantly downregulated in Co versus other groups. C-WL patients had lower handgrip strength, aLBM, and fat mass, and Eastern Cooperative Oncology Group and Karnofsky performance scores were lower in both cancer groups. GDF15, IL-6, and IL-8 significantly correlated with weight loss; GDF15 negatively correlated with aLBM, handgrip strength, and fat mass. IL-8 and Activin A negatively correlated with aLBM and fat mass. GDF15 and IL-8 predicted survival adjusting for stage and weight change (Cox regression P < 0.001 for both). Conclusion GDF15 and other inflammatory markers are associated with weight loss, decreased aLBM and strength, and poor survival in patients with cancer. GDF15 may serve as a prognostic indicator in cancer patients and is being evaluated as a potential therapeutic target for
... this page: //medlineplus.gov/ency/patientinstructions/000346.htm Weight-loss medicines To use the sharing features on this page, please enable JavaScript. Several weight-loss medicines are available. Ask your health care provider ...
... Sale You are here Home Diet and Nutrition Weight loss & acute Porphyria Being overweight is a particular problem ... one of these diseases before they enter a weight-loss program. Also, they should not participate in a ...
... below the minimum number of calories you need. Breastfeeding If you are breastfeeding, you will want to lose weight slowly. Weight ... not affect your milk supply or your health. Breastfeeding makes your body burn calories. It helps you ...
NASA Astrophysics Data System (ADS)
Farkas, Illés; Ábel, Dániel; Palla, Gergely; Vicsek, Tamás
2007-06-01
The inclusion of link weights into the analysis of network properties allows a deeper insight into the (often overlapping) modular structure of real-world webs. We introduce a clustering algorithm clique percolation method with weights (CPMw) for weighted networks based on the concept of percolating k-cliques with high enough intensity. The algorithm allows overlaps between the modules. First, we give detailed analytical and numerical results about the critical point of weighted k-clique percolation on (weighted) Erdos Rényi graphs. Then, for a scientist collaboration web and a stock correlation graph we compute three-link weight correlations and with the CPMw the weighted modules. After reshuffling link weights in both networks and computing the same quantities for the randomized control graphs as well, we show that groups of three or more strong links prefer to cluster together in both original graphs.
... Division (HMD) of the National Academies of Sciences, Engineering, and Medicine released updated guidelines for weight gain ... Division (HMD) of the National Academies of Sciences, Engineering, and Medicine: Weight Gain During Pregnancy: Reexamining the ...
ERIC Educational Resources Information Center
Clarke, Doug
1993-01-01
Describes an activity shared at an inservice teacher workshop and suitable for middle school in which students predict their ideal weight in kilograms based on tables giving ideal weights for given heights. (MDH)
Herring, Sharon J; Oken, Emily; Haines, Jess; Rich-Edwards, Janet W; Rifas-Shiman, Sheryl L; Kleinman ScD, Ken P; Gillman, Matthew W
2008-01-01
Background Excessive gestational weight gain promotes poor maternal and child health outcomes. Weight misperception is associated with weight gain in non-pregnant women, but no data exist during pregnancy. The purpose of this study was to examine the association of misperceived pre-pregnancy body weight status with excessive gestational weight gain. Methods At study enrollment, participants in Project Viva reported weight, height, and perceived body weight status by questionnaire. Our study sample comprised 1537 women who had either normal or overweight/obese pre-pregnancy BMI. We created 2 categories of pre-pregnancy body weight status misperception: normal weight women who identified themselves as overweight ('overassessors') and overweight/obese women who identified themselves as average or underweight ('underassessors'). Women who correctly perceived their body weight status were classified as either normal weight or overweight/obese accurate assessors. We performed multivariable logistic regression to determine the odds of excessive gestational weight gain according to 1990 Institute of Medicine guidelines. Results Of the 1029 women with normal pre-pregnancy BMI, 898 (87%) accurately perceived and 131 (13%) overassessed their weight status. 508 women were overweight/obese, of whom 438 (86%) accurately perceived and 70 (14%) underassessed their pre-pregnancy weight status. By the end of pregnancy, 823 women (54%) gained excessively. Compared with normal weight accurate assessors, the adjusted odds of excessive gestational weight gain was 2.0 (95% confidence interval [CI]: 1.3, 3.0) in normal weight overassessors, 2.9 (95% CI: 2.2, 3.9) in overweight/obese accurate assessors, and 7.6 (95% CI: 3.4, 17.0) in overweight/obese underassessors. Conclusion Misperceived pre-pregnancy body weight status was associated with excessive gestational weight gain among both normal weight and overweight/obese women, with the greatest likelihood of excessive gain among overweight
ERIC Educational Resources Information Center
Ryan, Kevin Michael
2011-01-01
Research on syllable weight in generative phonology has focused almost exclusively on systems in which weight is treated as an ordinal hierarchy of clearly delineated categories (e.g. light and heavy). As I discuss, canonical weight-sensitive phenomena in phonology, including quantitative meter and quantity-sensitive stress, can also treat weight…
Kriging without negative weights
Szidarovszky, F.; Baafi, E.Y.; Kim, Y.C.
1987-08-01
Under a constant drift, the linear kriging estimator is considered as a weighted average of n available sample values. Kriging weights are determined such that the estimator is unbiased and optimal. To meet these requirements, negative kriging weights are sometimes found. Use of negative weights can produce negative block grades, which makes no practical sense. In some applications, all kriging weights may be required to be nonnegative. In this paper, a derivation of a set of nonlinear equations with the nonnegative constraint is presented. A numerical algorithm also is developed for the solution of the new set of kriging equations.
Diagnosing underweight in adolescent girls: should we rely on self-reported height and weight?
Ohlmer, Ricarda; Jacobi, Corinna; Fittig, Eike
2012-01-01
This study examines the reliability of self-reported height, weight and weight change in underweight versus normal weight adolescent females. Self-reported height and weight were obtained from 162 schoolgirls without an eating disorder (12-16 years), and compared to objective measurements afterwards. Weight change was assessed 4 months later. The influence of age and current BMI on the reliability of self-reports was analyzed by linear regression analyses. With increasing age, height and BMI were reported more accurately. With increasing BMI, the underestimation of weight increased. Underweight girls overestimated their weight significantly compared to normal weight girls. Only 41% of the girls with a weight loss (>1 kg) in the past 4 months reported this accurately. Therefore, especially in younger girls with low body weight, information on height and weight as well as weight changes should be obtained objectively to identify a developing or subthreshold anorexia nervosa. PMID:22177388
1993-01-01
Low-birth-weight babies are most at risk of infant mortality. Unfortunately, in many developing countries it is not possible to weigh babies accurately because of the lack of robust scales. This article describes the results of a WHO Collaborative Study to investigate whether birth weight can be predicted accurately using chest circumference and/or arm circumference. The implications of the results for paediatric practice in developing countries are discussed. PMID:8490977
Deciphering faces: quantifiable visual cues to weight.
Coetzee, Vinet; Chen, Jingying; Perrett, David I; Stephen, Ian D
2010-01-01
Body weight plays a crucial role in mate choice, as weight is related to both attractiveness and health. People are quite accurate at judging weight in faces, but the cues used to make these judgments have not been defined. This study consisted of two parts. First, we wanted to identify quantifiable facial cues that are related to body weight, as defined by body mass index (BMI). Second, we wanted to test whether people use these cues to judge weight. In study 1, we recruited two groups of Caucasian and two groups of African participants, determined their BMI and measured their 2-D facial images for: width-to-height ratio, perimeter-to-area ratio, and cheek-to-jaw-width ratio. All three measures were significantly related to BMI in males, while the width-to-height and cheek-to-jaw-width ratios were significantly related to BMI in females. In study 2, these images were rated for perceived weight by Caucasian observers. We showed that these observers use all three cues to judge weight in African and Caucasian faces of both sexes. These three facial cues, width-to-height ratio, perimeter-to-area ratio, and cheek-to-jaw-width ratio, are therefore not only related to actual weight but provide a basis for perceptual attributes as well. PMID:20301846
Adolescent Suicidal Behavior Across the Excess Weight Status Spectrum
Zeller, Meg H.; Reiter-Purtill, Jennifer; Jenkins, Todd M.; Ratcliff, Megan B.
2013-01-01
The present study examined relative suicidal behavioral risks (ideation, attempts) for overweight, obese, and extremely obese adolescents (vs. healthy weight) and who did/did not accurately perceive themselves as overweight utilizing cross-sectional data from the publicly available Youth Risk Behavior Survey (YRBS). A new variable (weight status/accuracy) was computed that combined actual weight status (based on BMI) with weight perception accuracy. To evaluate the effect of weight status/accuracy on each suicidal risk behavior, logistic regression was performed to calculate odds-ratios and 95% confidence intervals (CI). Potential model covariates included gender, age, race, survey year, and whether they had felt sad/hopeless. Weight perception accuracy increased as the degree of excess weight increased. Relative to healthy weight, being obese or extremely obese (but not overweight) was associated with significantly greater risk for adolescent engagement in suicidal ideation, but was unrelated to suicide attempts. Adolescents in all excess weight categories who were accurate in their weight perception were at significantly greater odds of suicidal ideation, whereas those who were inaccurate of no greater odds of suicidal ideation than healthy weight youth who accurately perceived their weight. Findings regarding suicide attempts varied based on actual weight/weight perception accuracy and race/ethnicity. The present findings are both important and clinically relevant. While widely accepted that there are multiple pathways to suicide, our understanding of adolescent suicidal behavior risks and accordingly, prevention efforts, will be informed by comprehensive prospective studies that should also, from here forward, consider categorization of the entire weight spectrum (e.g., extreme obesity). PMID:23784908
Accurate Assessment--Compelling Evidence for Practice
ERIC Educational Resources Information Center
Flynn, Regina T.; Anderson, Ludmila; Martin, Nancy R.
2010-01-01
Childhood overweight and obesity is a public health concern not just because of its growing prevalence but also for its serious and lasting health consequences. Though height and weight measures are easy to obtain and New Hampshire Head Start sites measure height and weight of their enrollees, there are numerous challenges related to accurate…
Mill profiler machines soft materials accurately
NASA Technical Reports Server (NTRS)
Rauschl, J. A.
1966-01-01
Mill profiler machines bevels, slots, and grooves in soft materials, such as styrofoam phenolic-filled cores, to any desired thickness. A single operator can accurately control cutting depths in contour or straight line work.
Remote balance weighs accurately amid high radiation
NASA Technical Reports Server (NTRS)
Eggenberger, D. N.; Shuck, A. B.
1969-01-01
Commercial beam-type balance, modified and outfitted with electronic controls and digital readout, can be remotely controlled for use in high radiation environments. This allows accurate weighing of breeder-reactor fuel pieces when they are radioactively hot.
Understanding the Code: keeping accurate records.
Griffith, Richard
2015-10-01
In his continuing series looking at the legal and professional implications of the Nursing and Midwifery Council's revised Code of Conduct, Richard Griffith discusses the elements of accurate record keeping under Standard 10 of the Code. This article considers the importance of accurate record keeping for the safety of patients and protection of district nurses. The legal implications of records are explained along with how district nurses should write records to ensure these legal requirements are met. PMID:26418404
Biological mechanisms that promote weight regain following weight loss in obese humans.
Ochner, Christopher N; Barrios, Dulce M; Lee, Clement D; Pi-Sunyer, F Xavier
2013-08-15
Weight loss dieting remains the treatment of choice for the vast majority of obese individuals, despite the limited long-term success of behavioral weight loss interventions. The reasons for the near universal unsustainability of behavioral weight loss in [formerly] obese individuals have not been fully elucidated, relegating researchers to making educated guesses about how to improve obesity treatment, as opposed to developing interventions targeting the causes of weight regain. This article discusses research on several factors that may contribute to weight regain following weight loss achieved through behavioral interventions, including adipose cellularity, endocrine function, energy metabolism, neural responsivity, and addiction-like neural mechanisms. All of these mechanisms are engaged prior to weight loss, suggesting that these so called "anti-starvation" mechanisms are activated via reductions in energy intake, rather than depletion of energy stores. Evidence suggests that these mechanisms are not necessarily part of a homeostatic feedback system designed to regulate body weight, or even anti-starvation mechanisms per se. Although they may have evolved to prevent starvation, they appear to be more accurately described as anti-weight loss mechanisms, engaged with caloric restriction irrespective of the adequacy of energy stores. It is hypothesized that these factors may combine to create a biological disposition that fosters the maintenance of an elevated body weight and works to restore the highest sustained body weight, thus precluding the long-term success of behavioral weight loss. It may be necessary to develop interventions that attenuate these biological mechanisms in order to achieve long-term weight reduction in obese individuals. PMID:23911805
... trying to do so can have many causes. Metabolism slows down as you age . This can cause weight gain if you eat too much, eat the wrong foods, or do not get enough exercise. Drugs that can cause weight gain include: Birth control ...
... weight gain in a couple of ways. First, alcohol is high in calories. Some mixed drinks can contain as many calories as a meal, but without the nutrients. You also may make poor food choices ... to cut out all alcohol if you are trying to lose weight, you ...
Sansone, Randy A; Sansone, Lori A
2014-07-01
Acute marijuana use is classically associated with snacking behavior (colloquially referred to as "the munchies"). In support of these acute appetite-enhancing effects, several authorities report that marijuana may increase body mass index in patients suffering from human immunodeficiency virus and cancer. However, for these medical conditions, while appetite may be stimulated, some studies indicate that weight gain is not always clinically meaningful. In addition, in a study of cancer patients in which weight gain did occur, it was less than the comparator drug (megestrol). However, data generally suggest that acute marijuana use stimulates appetite, and that marijuana use may stimulate appetite in low-weight individuals. As for large epidemiological studies in the general population, findings consistently indicate that users of marijuana tend to have lower body mass indices than nonusers. While paradoxical and somewhat perplexing, these findings may be explained by various study confounds, such as potential differences between acute versus chronic marijuana use; the tendency for marijuana use to be associated with other types of drug use; and/or the possible competition between food and drugs for the same reward sites in the brain. Likewise, perhaps the effects of marijuana are a function of initial weight status-i.e., maybe marijuana is a metabolic regulatory substance that increases body weight in low-weight individuals but not in normal-weight or overweight individuals. Only further research will clarify the complex relationships between marijuana and body weight. PMID:25337447
ERIC Educational Resources Information Center
Katch, Victor L.
This paper describes a number of factors which go into determining weight. The paper describes what calories are, how caloric expenditure is measured, and why caloric expenditure is different for different people. The paper then outlines the way the body tends to adjust food intake and exercise to maintain a constant body weight. It is speculated…
Technology Transfer Automated Retrieval System (TEKTRAN)
This review evaluated the available scientific literature relative to anthocyanins and weight loss and/or obesity with mention of other effects of anthocyanins on pathologies that are closely related to obesity. Although there is considerable popular press concerning anthocyanins and weight loss, th...
ERIC Educational Resources Information Center
Francis, Richard L.
1992-01-01
Presents the template method developed by Galileo for calculating areas of geometric shapes constructed of uniform density and thickness. The method compares the weight of a shape of known area to the weight of a shape of unknown area. Applies this hands-on method to problems involving calculus, Pythagorean's theorem, and cycloids. (MDH)
... in a person's diabetes management plan. Weight and Type 1 Diabetes If a person has type 1 diabetes but hasn't been treated yet, he or she often loses weight. In type 1 diabetes, the body can't use glucose (pronounced: GLOO- ...
ERIC Educational Resources Information Center
Lakdawalla, Darius; Philipson, Tomas
2007-01-01
We use panel data from the National Longitudinal Survey of Youth to investigate on-the-job exercise and weight. For male workers, job-related exercise has causal effects on weight, but for female workers, the effects seem primarily selective. A man who spends 18 years in the most physical fitness-demanding occupation is about 25 pounds (14…
... 22990030 www.ncbi.nlm.nih.gov/pubmed/22990030 . Weight-control Information NetworkNational Institute of Diabetes and Digestive and ... www.niddk.nih.gov/health-information/health-topics/weight-control/very-low-calorie-diets/Pages/very-low-calorie- ...
Weight, Weight Perceptions and Health-Related Quality of Life among a National Sample of US Girls
Farhat, Tilda; Iannotti, Ronald J.; Summersett-Ringgold, Faith
2015-01-01
Objective To examine associations between three weight indices (weight status, perceived weight, weight status perception accuracy) and HRQOL. Methods Data are for girls in the 2009 Health Behaviors in School-Age Children survey, a nationally representative sample of students in grades 5-10 during the 2009/10 school-year (n=5,018). Controlling for sociodemographics, multivariate linear regressions examined associations between self-reported weight status (Underweight/Normal/Overweight/Obese), perceived weight (how children categorize their weight), weight status perception accuracy (Underestimate/Accurate perception/Overestimate) and dimensions of HRQOL including physical, emotional, social, and school functioning. Results While obesity was only associated with poor physical and emotional HRQOL, perceptions of being overweight were associated with worse physical, emotional, school and social HRQOL. Further, girls who overestimated their weight reported poorer HRQOL than those with accurate weight perceptions. Associations of perceptions of being overweight and weight status overestimation with poor HRQOL despite, in most instances, the absence of associations between weight status and HRQOL, suggest that weight status perceptions may not merely be a mediator of a weight status-HRQOL association, but a significant independent correlate of poor HRQOL. Conclusion These findings raise the issue of whether there is a need to prioritize intervention efforts to promote better HRQOL by re-defining the population of girls most at risk. Parents, teachers and clinicians should be aware that, rather that overweight status, perceptions of being overweight (accurately or not) are associated with a poor HRQOL among girls. Future research should examine the potential negative effect of using specific body image terminologies on adolescents' psychological health. PMID:25961900
Do mother's interests in weight control influence preschoolers' obesity and weight related concerns?
2007-01-01
The purpose of this study was to assess the relationship between the mother's interest in weight control and its association with the preschooler's obesity and weight related concerns. This was a cross-sectional study based on 470 parents' self-reports. To score interests in weight control, mothers rated each of 6 items on a five-point Likert scale ranging from disagree (1) to agree (5). The perceptions of mothers' weights and their children's weights, mothers' Body Mass Index (BMI), preschoolers' Weight-Length Index (WLI) (%), and weight-related concerns were determined. The mothers' BMI was significantly correlated with interest scores of weight control in mothers (r=0.632, p<0.001) while their children's obesity was weakly correlated with the mothers' interest scores (r=0.133, p=0.025). Mothers with a high interest of weight control reported higher percentages of family history of obesity than mothers with lower interests (63.2% vs. 36.8%, p<0.001). Two-thirds of the mothers (65.4%) were accurate in their perceptions about their weights. Similarly, 63.7% of mothers knew exactly their children's weight-statuses. Compared with mothers with low interest in weight controls, mothers with high interest in weight control had lower correct-perceptions about their weights (p<0.05) but higher correct-perceptions about their children's weights. More than two-thirds of mothers (85%) reported not worrying about their children's obesity in the future. Only 14.3% of the mothers were satisfied with their current weight statuses. Three-fourths of mothers preferred exercise as an effective weight-control method for their children, 20% preferred diet therapy and 5.5% preferred behavior modification. More girls were overweight / obese, than boys (overweight: 16.1% (girl) vs. 12.8% (boy), obese: 5.4% (girl) vs. 4.5% (boy)). About 40% of overweight girls' mothers had low interests in their weight controls with low correct-perceptions in their children's weights, which suggests
Weight discrimination and bullying.
Puhl, Rebecca M; King, Kelly M
2013-04-01
Despite significant attention to the medical impacts of obesity, often ignored are the negative outcomes that obese children and adults experience as a result of stigma, bias, and discrimination. Obese individuals are frequently stigmatized because of their weight in many domains of daily life. Research spanning several decades has documented consistent weight bias and stigmatization in employment, health care, schools, the media, and interpersonal relationships. For overweight and obese youth, weight stigmatization translates into pervasive victimization, teasing, and bullying. Multiple adverse outcomes are associated with exposure to weight stigmatization, including depression, anxiety, low self-esteem, body dissatisfaction, suicidal ideation, poor academic performance, lower physical activity, maladaptive eating behaviors, and avoidance of health care. This review summarizes the nature and extent of weight stigmatization against overweight and obese individuals, as well as the resulting consequences that these experiences create for social, psychological, and physical health for children and adults who are targeted. PMID:23731874
ERIC Educational Resources Information Center
Park, Eunkyung
2011-01-01
Background: Weight perception has been studied with a limited focus on "feeling overweight." This study, using a more inclusive definition of overestimation and underestimation, examines adolescents' weight perception focusing on how accurate it is in relation to body mass index (BMI)-based weight status and how it varies across socio-demographic…
Steinke, Hanno; Rabi, Suganthy; Saito, Toshiyuki; Sawutti, Alimjan; Miyaki, Takayoshi; Itoh, Masahiro; Spanel-Borowski, Katharina
2008-11-20
Plastination is an excellent technique which helps to keep the anatomical specimens in a dry, odourless state. Since the invention of plastination technique by von Hagens, research has been done to improve the quality of plastinated specimens. In this paper, we have described a method of producing light-weight plastinated specimens using xylene along with silicone and in the final step, substitute xylene with air. The finished plastinated specimens were light-weight, dry, odourless and robust. This method requires less use of resin thus making the plastination technique more cost-effective. The light-weight specimens are easy to carry and can easily be used for teaching. PMID:18752934
Robust, accurate and fast automatic segmentation of the spinal cord.
De Leener, Benjamin; Kadoury, Samuel; Cohen-Adad, Julien
2014-09-01
Spinal cord segmentation provides measures of atrophy and facilitates group analysis via inter-subject correspondence. Automatizing this procedure enables studies with large throughput and minimizes user bias. Although several automatic segmentation methods exist, they are often restricted in terms of image contrast and field-of-view. This paper presents a new automatic segmentation method (PropSeg) optimized for robustness, accuracy and speed. The algorithm is based on the propagation of a deformable model and is divided into three parts: firstly, an initialization step detects the spinal cord position and orientation using a circular Hough transform on multiple axial slices rostral and caudal to the starting plane and builds an initial elliptical tubular mesh. Secondly, a low-resolution deformable model is propagated along the spinal cord. To deal with highly variable contrast levels between the spinal cord and the cerebrospinal fluid, the deformation is coupled with a local contrast-to-noise adaptation at each iteration. Thirdly, a refinement process and a global deformation are applied on the propagated mesh to provide an accurate segmentation of the spinal cord. Validation was performed in 15 healthy subjects and two patients with spinal cord injury, using T1- and T2-weighted images of the entire spinal cord and on multiecho T2*-weighted images. Our method was compared against manual segmentation and against an active surface method. Results show high precision for all the MR sequences. Dice coefficients were 0.9 for the T1- and T2-weighted cohorts and 0.86 for the T2*-weighted images. The proposed method runs in less than 1min on a normal computer and can be used to quantify morphological features such as cross-sectional area along the whole spinal cord. PMID:24780696
A highly accurate interatomic potential for argon
NASA Astrophysics Data System (ADS)
Aziz, Ronald A.
1993-09-01
A modified potential based on the individually damped model of Douketis, Scoles, Marchetti, Zen, and Thakkar [J. Chem. Phys. 76, 3057 (1982)] is presented which fits, within experimental error, the accurate ultraviolet (UV) vibration-rotation spectrum of argon determined by UV laser absorption spectroscopy by Herman, LaRocque, and Stoicheff [J. Chem. Phys. 89, 4535 (1988)]. Other literature potentials fail to do so. The potential also is shown to predict a large number of other properties and is probably the most accurate characterization of the argon interaction constructed to date.
Englberger, L.
1999-01-01
A programme of weight loss competitions and associated activities in Tonga, intended to combat obesity and the noncommunicable diseases linked to it, has popular support and the potential to effect significant improvements in health. PMID:10063662
... Differences in BMRs are associated with changes in energy balance. Energy balance reflects the difference between the amount of ... such as amphetamines, animals often have a negative energy balance which leads to weight loss. Based on ...
... behavioral guidelines for post-partum weight control. BMC Pregnancy and Childbirth . 2014;14. Accessed Nov. 24, 2014. Mottola MF. Exercise prescription for overweight and obese women: pregnancy and ...
... of laxatives Other causes such as: Eating disorders, anorexia nervosa that have not been diagnosed yet Diabetes that ... do not know the reason. You have other symptoms along with the weight loss.
... Global Map Premature birth report card Careers Archives Pregnancy Before or between pregnancies Nutrition, weight & fitness Prenatal ... Zika virus and pregnancy Microcephaly Medicine safety and pregnancy Birth defects prevention Learn how to help reduce ...
... If this is the case, preventing further weight gain is a worthy goal. As people age, their body composition gradually shifts â€” the proportion of muscle decreases and the proportion of fat increases. This ...
... spurts in height and weight gain in both boys and girls. Once these changes start, they continue for several ... or obese . Different BMI charts are used for boys and girls under the age of 20 because the amount ...
Validity of Mothers' Reports of Children's Weight in Japan.
Nosaka, Nobuyuki; Fujiwara, Takeo; Knaup, Emily; Okada, Ayumi; Tsukahara, Hirokazu
2016-08-01
Estimation methods for pediatric weight have not been evaluated for Japanese children. This study aimed to assess the accuracy of mothers' reports of their children's weight in Japan. We also evaluated potential alternatives to the estimation of weight, including the Broselow tape (BT), Advanced Pediatric Life Support (APLS), and Park's formulae. We prospectively collected cross-sectional data on a convenience sample of 237 children aged less than 10 years who presented to a general pediatric outpatient clinic with their mothers. Each weight estimation method was evaluated using Bland- Altman plots and by calculating the proportion within 10% and 20% of the measured weight. Mothers' reports of weight were the most accurate method, with 94.9% within 10% of the measured weight, the lowest mean difference (0.27kg), and the shortest 95% limit of agreement (－1.4 to 1.9kg). The BT was the most reliable alternative, followed by APLS and Park's formulae. Mothers' reports of their children 's weight are more accurate than other weight estimation methods. When no report of a child's weight by the mother is available, BT is the best alternative. When an aged-based formula is the only option, the APLS formula is preferred. PMID:27549669
Correctly Expressing Atomic Weights
NASA Astrophysics Data System (ADS)
Paolini, Moreno; Cercignani, Giovanni; Bauer, Carlo
2000-11-01
Very often, atomic or molecular weights are expressed as dimensionless quantities, but although the historical importance of their definition as "pure numbers" is acknowledged, it is inconsistent with experimental formulas and with the theory of measure in general. Here, we propose on the basis of clear-cut formulas that, contrary to customary statements, atomic and molecular weights should be expressed as dimensional quantities (masses) in which the Dalton (= 1.663 x 10-24 g) is taken as the unit.
Vulnerability of weighted networks
NASA Astrophysics Data System (ADS)
Dall'Asta, Luca; Barrat, Alain; Barthélemy, Marc; Vespignani, Alessandro
2006-04-01
In real networks complex topological features are often associated with a diversity of interactions as measured by the weights of the links. Moreover, spatial constraints may also play an important role, resulting in a complex interplay between topology, weight, and geography. In order to study the vulnerability of such networks to intentional attacks, these attributes must therefore be considered along with the topological quantities. In order to tackle this issue, we consider the case of the worldwide airport network, which is a weighted heterogeneous network whose evolution and structure are influenced by traffic and geographical constraints. We first characterize relevant topological and weighted centrality measures and then use these quantities as selection criteria for the removal of vertices. We consider different attack strategies and different measures of the damage achieved in the network. The analysis of weighted properties shows that centrality driven attacks are capable of shattering the network's communication or transport properties even at a very low level of damage in the connectivity pattern. The inclusion of weight and traffic therefore provides evidence for the extreme vulnerability of complex networks to any targeted strategy and the need for them to be considered as key features in the finding and development of defensive strategies.
Accurate pointing of tungsten welding electrodes
NASA Technical Reports Server (NTRS)
Ziegelmeier, P.
1971-01-01
Thoriated-tungsten is pointed accurately and quickly by using sodium nitrite. Point produced is smooth and no effort is necessary to hold the tungsten rod concentric. The chemically produced point can be used several times longer than ground points. This method reduces time and cost of preparing tungsten electrodes.
A new accurate pill recognition system using imprint information
NASA Astrophysics Data System (ADS)
Chen, Zhiyuan; Kamata, Sei-ichiro
2013-12-01
Great achievements in modern medicine benefit human beings. Also, it has brought about an explosive growth of pharmaceuticals that current in the market. In daily life, pharmaceuticals sometimes confuse people when they are found unlabeled. In this paper, we propose an automatic pill recognition technique to solve this problem. It functions mainly based on the imprint feature of the pills, which is extracted by proposed MSWT (modified stroke width transform) and described by WSC (weighted shape context). Experiments show that our proposed pill recognition method can reach an accurate rate up to 92.03% within top 5 ranks when trying to classify more than 10 thousand query pill images into around 2000 categories.
Accurate finite difference methods for time-harmonic wave propagation
NASA Technical Reports Server (NTRS)
Harari, Isaac; Turkel, Eli
1994-01-01
Finite difference methods for solving problems of time-harmonic acoustics are developed and analyzed. Multidimensional inhomogeneous problems with variable, possibly discontinuous, coefficients are considered, accounting for the effects of employing nonuniform grids. A weighted-average representation is less sensitive to transition in wave resolution (due to variable wave numbers or nonuniform grids) than the standard pointwise representation. Further enhancement in method performance is obtained by basing the stencils on generalizations of Pade approximation, or generalized definitions of the derivative, reducing spurious dispersion, anisotropy and reflection, and by improving the representation of source terms. The resulting schemes have fourth-order accurate local truncation error on uniform grids and third order in the nonuniform case. Guidelines for discretization pertaining to grid orientation and resolution are presented.
Accurate Anisotropic Fast Marching for Diffusion-Based Geodesic Tractography
Jbabdi, S.; Bellec, P.; Toro, R.; Daunizeau, J.; Pélégrini-Issac, M.; Benali, H.
2008-01-01
Using geodesics for inferring white matter fibre tracts from diffusion-weighted MR data is an attractive method for at least two reasons: (i) the method optimises a global criterion, and hence is less sensitive to local perturbations such as noise or partial volume effects, and (ii) the method is fast, allowing to infer on a large number of connexions in a reasonable computational time. Here, we propose an improved fast marching algorithm to infer on geodesic paths. Specifically, this procedure is designed to achieve accurate front propagation in an anisotropic elliptic medium, such as DTI data. We evaluate the numerical performance of this approach on simulated datasets, as well as its robustness to local perturbation induced by fiber crossing. On real data, we demonstrate the feasibility of extracting geodesics to connect an extended set of brain regions. PMID:18299703
Weight Loss Nutritional Supplements
NASA Astrophysics Data System (ADS)
Eckerson, Joan M.
Obesity has reached what may be considered epidemic proportions in the United States, not only for adults but for children. Because of the medical implications and health care costs associated with obesity, as well as the negative social and psychological impacts, many individuals turn to nonprescription nutritional weight loss supplements hoping for a quick fix, and the weight loss industry has responded by offering a variety of products that generates billions of dollars each year in sales. Most nutritional weight loss supplements are purported to work by increasing energy expenditure, modulating carbohydrate or fat metabolism, increasing satiety, inducing diuresis, or blocking fat absorption. To review the literally hundreds of nutritional weight loss supplements available on the market today is well beyond the scope of this chapter. Therefore, several of the most commonly used supplements were selected for critical review, and practical recommendations are provided based on the findings of well controlled, randomized clinical trials that examined their efficacy. In most cases, the nutritional supplements reviewed either elicited no meaningful effect or resulted in changes in body weight and composition that are similar to what occurs through a restricted diet and exercise program. Although there is some evidence to suggest that herbal forms of ephedrine, such as ma huang, combined with caffeine or caffeine and aspirin (i.e., ECA stack) is effective for inducing moderate weight loss in overweight adults, because of the recent ban on ephedra manufacturers must now use ephedra-free ingredients, such as bitter orange, which do not appear to be as effective. The dietary fiber, glucomannan, also appears to hold some promise as a possible treatment for weight loss, but other related forms of dietary fiber, including guar gum and psyllium, are ineffective.
Microbalance accurately measures extremely small masses
NASA Technical Reports Server (NTRS)
Patashnick, H.
1970-01-01
Oscillating fiber microbalance has a vibrating quartz fiber as balance arm to hold the mass to be weighed. Increasing fiber weight decreases its resonant frequency. Scaler and timer measure magnitude of the shift. This instrument withstands considerable physical abuse and has calibration stability at normal room temperatures.
Popular weight reduction diets.
Volpe, Stella Lucia
2006-01-01
The percentage of people who are overweight and obese has increased tremendously over the last 30 years. It has become a worldwide epidemic. This is evident by the number of children are being diagnosed with a body mass index >85th percentile, and the number of children begin diagnosed with type 2 diabetes mellitus, a disease previously reserved for adults. The weight loss industry has also gained from this epidemic; it is a billion dollar industry. People pay large sums of money on diet pills, remedies, and books, with the hope of losing weight permanently. Despite these efforts, the number of individuals who are overweight or obese continues to increase. Obesity is a complex, multifactorial disorder. It would be impossible to address all aspects of diet, exercise, and weight loss in this review. Therefore, this article will review popular weight loss diets, with particular attention given to comparing low fat diets with low carbohydrate diets. In addition, the role that the environment plays on both diet and exercise and how they impact obesity will be addressed. Finally, the National Weight Control Registry will be discussed. PMID:16407735
Lorcaserin for weight management
Taylor, James R; Dietrich, Eric; Powell, Jason
2013-01-01
Type 2 diabetes and obesity commonly occur together. Obesity contributes to insulin resistance, a main cause of type 2 diabetes. Modest weight loss reduces glucose, lipids, blood pressure, need for medications, and cardiovascular risk. A number of approaches can be used to achieve weight loss, including lifestyle modification, surgery, and medication. Lorcaserin, a novel antiobesity agent, affects central serotonin subtype 2A receptors, resulting in decreased food intake and increased satiety. It has been studied in obese patients with type 2 diabetes and results in an approximately 5.5 kg weight loss, on average, when used for one year. Headache, back pain, nasopharyngitis, and nausea were the most common adverse effects noted with lorcaserin. Hypoglycemia was more common in the lorcaserin groups in the clinical trials, but none of the episodes were categorized as severe. Based on the results of these studies, lorcaserin was approved at a dose of 10 mg twice daily in patients with a body mass index ≥30 kg/m2 or ≥27 kg/m2 with at least one weight-related comorbidity, such as hypertension, type 2 diabetes mellitus, or dyslipidemia, in addition to a reduced calorie diet and increased physical activity. Lorcaserin is effective for weight loss in obese patients with and without type 2 diabetes, although its specific role in the management of obesity is unclear at this time. This paper reviews the clinical trials of lorcaserin, its use from the patient perspective, and its potential role in the treatment of obesity. PMID:23788837
ERIC Educational Resources Information Center
Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi
2012-01-01
One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected by feedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On Day 1, participants performed a golf putting task under one of…
Exploring accurate Poisson–Boltzmann methods for biomolecular simulations
Wang, Changhao; Wang, Jun; Cai, Qin; Li, Zhilin; Zhao, Hong-Kai; Luo, Ray
2013-01-01
Accurate and efficient treatment of electrostatics is a crucial step in computational analyses of biomolecular structures and dynamics. In this study, we have explored a second-order finite-difference numerical method to solve the widely used Poisson–Boltzmann equation for electrostatic analyses of realistic bio-molecules. The so-called immersed interface method was first validated and found to be consistent with the classical weighted harmonic averaging method for a diversified set of test biomolecules. The numerical accuracy and convergence behaviors of the new method were next analyzed in its computation of numerical reaction field grid potentials, energies, and atomic solvation forces. Overall similar convergence behaviors were observed as those by the classical method. Interestingly, the new method was found to deliver more accurate and better-converged grid potentials than the classical method on or nearby the molecular surface, though the numerical advantage of the new method is reduced when grid potentials are extrapolated to the molecular surface. Our exploratory study indicates the need for further improving interpolation/extrapolation schemes in addition to the developments of higher-order numerical methods that have attracted most attention in the field. PMID:24443709
Robust ODF smoothing for accurate estimation of fiber orientation.
Beladi, Somaieh; Pathirana, Pubudu N; Brotchie, Peter
2010-01-01
Q-ball imaging was presented as a model free, linear and multimodal diffusion sensitive approach to reconstruct diffusion orientation distribution function (ODF) using diffusion weighted MRI data. The ODFs are widely used to estimate the fiber orientations. However, the smoothness constraint was proposed to achieve a balance between the angular resolution and noise stability for ODF constructs. Different regularization methods were proposed for this purpose. However, these methods are not robust and quite sensitive to the global regularization parameter. Although, numerical methods such as L-curve test are used to define a globally appropriate regularization parameter, it cannot serve as a universal value suitable for all regions of interest. This may result in over smoothing and potentially end up in neglecting an existing fiber population. In this paper, we propose to include an interpolation step prior to the spherical harmonic decomposition. This interpolation based approach is based on Delaunay triangulation provides a reliable, robust and accurate smoothing approach. This method is easy to implement and does not require other numerical methods to define the required parameters. Also, the fiber orientations estimated using this approach are more accurate compared to other common approaches. PMID:21096202
Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi
2012-06-01
One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected byfeedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On day 1, participants performed a golf putting task under one of two conditions: one group received feedback on the most accurate trials, whereas another group received feedback on the least accurate trials. On day 2, participants completed an anxiety questionnaire and performed a retention test. Shin conductance level, as a measure of arousal, was determined. The results indicated that feedback about more accurate trials resulted in more effective learning as well as increased self-confidence. Also, activation was a predictor of performance. PMID:22808705
NASA Astrophysics Data System (ADS)
Bradley-Hutchison, Doug
2014-11-01
Once a controversial idea, the fact that gases like air have weight can easily be demonstrated using reasonably precise scales in the modern teaching laboratory. But unlike a liquid, where a mechanical model suggests a pile of hard spheres resting on each other, gas molecules are in continual motion and can have minimal interaction. How should we think about the effect these molecules have on the scale? And more importantly, how should we explain it to students? Several models of gas behavior are employed to answer these questions and it is shown how the weight of a gas is, like electric current, an emergent phenomena in contrast to the weight of a liquid which is direct or causal.
Sethi, Bipin Kumar; Nagesh, V Sri
2015-05-01
Ramadan fasting is associated with significant weight loss in both men and women. Reduction in blood pressure, lipids, blood glucose, body mass index and waist and hip circumference may also occur. However, benefits accrued during this month often reverse within a few weeks of cessation of fasting, with most people returning back to their pre-Ramadan body weights and body composition. To ensure maintenance of this fasting induced weight loss, health care professionals should encourage continuation of healthy dietary habits, moderate physical activity and behaviour modification, even after conclusion of fasting. It should be realized that Ramadan is an ideal platform to target year long lifestyle modification, to ensure that whatever health care benefits have been gained during this month, are perpetuated. PMID:26013789
Generalized constructive tree weights
Rivasseau, Vincent E-mail: adrian.tanasa@ens-lyon.org; Tanasa, Adrian E-mail: adrian.tanasa@ens-lyon.org
2014-04-15
The Loop Vertex Expansion (LVE) is a quantum field theory (QFT) method which explicitly computes the Borel sum of Feynman perturbation series. This LVE relies in a crucial way on symmetric tree weights which define a measure on the set of spanning trees of any connected graph. In this paper we generalize this method by defining new tree weights. They depend on the choice of a partition of a set of vertices of the graph, and when the partition is non-trivial, they are no longer symmetric under permutation of vertices. Nevertheless we prove they have the required positivity property to lead to a convergent LVE; in fact we formulate this positivity property precisely for the first time. Our generalized tree weights are inspired by the Brydges-Battle-Federbush work on cluster expansions and could be particularly suited to the computation of connected functions in QFT. Several concrete examples are explicitly given.
Evers, Daan
2013-04-01
According to Stephen Finlay, 'A ought to X' means that X-ing is more conducive to contextually salient ends than relevant alternatives. This in turn is analysed in terms of probability. I show why this theory of 'ought' is hard to square with a theory of a reason's weight which could explain why 'A ought to X' logically entails that the balance of reasons favours that A X-es. I develop two theories of weight to illustrate my point. I first look at the prospects of a theory of weight based on expected utility theory. I then suggest a simpler theory. Although neither allows that 'A ought to X' logically entails that the balance of reasons favours that A X-es, this price may be accepted. For there remains a strong pragmatic relation between these claims. PMID:23576822
Light weight phosphate cements
Wagh, Arun S.; Natarajan, Ramkumar,; Kahn, David
2010-03-09
A sealant having a specific gravity in the range of from about 0.7 to about 1.6 for heavy oil and/or coal bed methane fields is disclosed. The sealant has a binder including an oxide or hydroxide of Al or of Fe and a phosphoric acid solution. The binder may have MgO or an oxide of Fe and/or an acid phosphate. The binder is present from about 20 to about 50% by weight of the sealant with a lightweight additive present in the range of from about 1 to about 10% by weight of said sealant, a filler, and water sufficient to provide chemically bound water present in the range of from about 9 to about 36% by weight of the sealant when set. A porous ceramic is also disclosed.
D-BRAIN: Anatomically Accurate Simulated Diffusion MRI Brain Data.
Perrone, Daniele; Jeurissen, Ben; Aelterman, Jan; Roine, Timo; Sijbers, Jan; Pizurica, Aleksandra; Leemans, Alexander; Philips, Wilfried
2016-01-01
Diffusion Weighted (DW) MRI allows for the non-invasive study of water diffusion inside living tissues. As such, it is useful for the investigation of human brain white matter (WM) connectivity in vivo through fiber tractography (FT) algorithms. Many DW-MRI tailored restoration techniques and FT algorithms have been developed. However, it is not clear how accurately these methods reproduce the WM bundle characteristics in real-world conditions, such as in the presence of noise, partial volume effect, and a limited spatial and angular resolution. The difficulty lies in the lack of a realistic brain phantom on the one hand, and a sufficiently accurate way of modeling the acquisition-related degradation on the other. This paper proposes a software phantom that approximates a human brain to a high degree of realism and that can incorporate complex brain-like structural features. We refer to it as a Diffusion BRAIN (D-BRAIN) phantom. Also, we propose an accurate model of a (DW) MRI acquisition protocol to allow for validation of methods in realistic conditions with data imperfections. The phantom model simulates anatomical and diffusion properties for multiple brain tissue components, and can serve as a ground-truth to evaluate FT algorithms, among others. The simulation of the acquisition process allows one to include noise, partial volume effects, and limited spatial and angular resolution in the images. In this way, the effect of image artifacts on, for instance, fiber tractography can be investigated with great detail. The proposed framework enables reliable and quantitative evaluation of DW-MR image processing and FT algorithms at the level of large-scale WM structures. The effect of noise levels and other data characteristics on cortico-cortical connectivity and tractography-based grey matter parcellation can be investigated as well. PMID:26930054
D-BRAIN: Anatomically Accurate Simulated Diffusion MRI Brain Data
Perrone, Daniele; Jeurissen, Ben; Aelterman, Jan; Roine, Timo; Sijbers, Jan; Pizurica, Aleksandra; Leemans, Alexander; Philips, Wilfried
2016-01-01
Diffusion Weighted (DW) MRI allows for the non-invasive study of water diffusion inside living tissues. As such, it is useful for the investigation of human brain white matter (WM) connectivity in vivo through fiber tractography (FT) algorithms. Many DW-MRI tailored restoration techniques and FT algorithms have been developed. However, it is not clear how accurately these methods reproduce the WM bundle characteristics in real-world conditions, such as in the presence of noise, partial volume effect, and a limited spatial and angular resolution. The difficulty lies in the lack of a realistic brain phantom on the one hand, and a sufficiently accurate way of modeling the acquisition-related degradation on the other. This paper proposes a software phantom that approximates a human brain to a high degree of realism and that can incorporate complex brain-like structural features. We refer to it as a Diffusion BRAIN (D-BRAIN) phantom. Also, we propose an accurate model of a (DW) MRI acquisition protocol to allow for validation of methods in realistic conditions with data imperfections. The phantom model simulates anatomical and diffusion properties for multiple brain tissue components, and can serve as a ground-truth to evaluate FT algorithms, among others. The simulation of the acquisition process allows one to include noise, partial volume effects, and limited spatial and angular resolution in the images. In this way, the effect of image artifacts on, for instance, fiber tractography can be investigated with great detail. The proposed framework enables reliable and quantitative evaluation of DW-MR image processing and FT algorithms at the level of large-scale WM structures. The effect of noise levels and other data characteristics on cortico-cortical connectivity and tractography-based grey matter parcellation can be investigated as well. PMID:26930054
New model accurately predicts reformate composition
Ancheyta-Juarez, J.; Aguilar-Rodriguez, E. )
1994-01-31
Although naphtha reforming is a well-known process, the evolution of catalyst formulation, as well as new trends in gasoline specifications, have led to rapid evolution of the process, including: reactor design, regeneration mode, and operating conditions. Mathematical modeling of the reforming process is an increasingly important tool. It is fundamental to the proper design of new reactors and revamp of existing ones. Modeling can be used to optimize operating conditions, analyze the effects of process variables, and enhance unit performance. Instituto Mexicano del Petroleo has developed a model of the catalytic reforming process that accurately predicts reformate composition at the higher-severity conditions at which new reformers are being designed. The new AA model is more accurate than previous proposals because it takes into account the effects of temperature and pressure on the rate constants of each chemical reaction.
Accurate colorimetric feedback for RGB LED clusters
NASA Astrophysics Data System (ADS)
Man, Kwong; Ashdown, Ian
2006-08-01
We present an empirical model of LED emission spectra that is applicable to both InGaN and AlInGaP high-flux LEDs, and which accurately predicts their relative spectral power distributions over a wide range of LED junction temperatures. We further demonstrate with laboratory measurements that changes in LED spectral power distribution with temperature can be accurately predicted with first- or second-order equations. This provides the basis for a real-time colorimetric feedback system for RGB LED clusters that can maintain the chromaticity of white light at constant intensity to within +/-0.003 Δuv over a range of 45 degrees Celsius, and to within 0.01 Δuv when dimmed over an intensity range of 10:1.
Accurate mask model for advanced nodes
NASA Astrophysics Data System (ADS)
Zine El Abidine, Nacer; Sundermann, Frank; Yesilada, Emek; Ndiaye, El Hadji Omar; Mishra, Kushlendra; Paninjath, Sankaranarayanan; Bork, Ingo; Buck, Peter; Toublan, Olivier; Schanen, Isabelle
2014-07-01
Standard OPC models consist of a physical optical model and an empirical resist model. The resist model compensates the optical model imprecision on top of modeling resist development. The optical model imprecision may result from mask topography effects and real mask information including mask ebeam writing and mask process contributions. For advanced technology nodes, significant progress has been made to model mask topography to improve optical model accuracy. However, mask information is difficult to decorrelate from standard OPC model. Our goal is to establish an accurate mask model through a dedicated calibration exercise. In this paper, we present a flow to calibrate an accurate mask enabling its implementation. The study covers the different effects that should be embedded in the mask model as well as the experiment required to model them.
Accurate guitar tuning by cochlear implant musicians.
Lu, Thomas; Huang, Juan; Zeng, Fan-Gang
2014-01-01
Modern cochlear implant (CI) users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼ 30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task. PMID:24651081
Two highly accurate methods for pitch calibration
NASA Astrophysics Data System (ADS)
Kniel, K.; Härtig, F.; Osawa, S.; Sato, O.
2009-11-01
Among profiles, helix and tooth thickness pitch is one of the most important parameters of an involute gear measurement evaluation. In principle, coordinate measuring machines (CMM) and CNC-controlled gear measuring machines as a variant of a CMM are suited for these kinds of gear measurements. Now the Japan National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) and the German national metrology institute the Physikalisch-Technische Bundesanstalt (PTB) have each developed independently highly accurate pitch calibration methods applicable to CMM or gear measuring machines. Both calibration methods are based on the so-called closure technique which allows the separation of the systematic errors of the measurement device and the errors of the gear. For the verification of both calibration methods, NMIJ/AIST and PTB performed measurements on a specially designed pitch artifact. The comparison of the results shows that both methods can be used for highly accurate calibrations of pitch standards.
Accurate modeling of parallel scientific computations
NASA Technical Reports Server (NTRS)
Nicol, David M.; Townsend, James C.
1988-01-01
Scientific codes are usually parallelized by partitioning a grid among processors. To achieve top performance it is necessary to partition the grid so as to balance workload and minimize communication/synchronization costs. This problem is particularly acute when the grid is irregular, changes over the course of the computation, and is not known until load time. Critical mapping and remapping decisions rest on the ability to accurately predict performance, given a description of a grid and its partition. This paper discusses one approach to this problem, and illustrates its use on a one-dimensional fluids code. The models constructed are shown to be accurate, and are used to find optimal remapping schedules.
Accurate Guitar Tuning by Cochlear Implant Musicians
Lu, Thomas; Huang, Juan; Zeng, Fan-Gang
2014-01-01
Modern cochlear implant (CI) users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task. PMID:24651081
An accurate registration technique for distorted images
NASA Technical Reports Server (NTRS)
Delapena, Michele; Shaw, Richard A.; Linde, Peter; Dravins, Dainis
1990-01-01
Accurate registration of International Ultraviolet Explorer (IUE) images is crucial because the variability of the geometrical distortions that are introduced by the SEC-Vidicon cameras ensures that raw science images are never perfectly aligned with the Intensity Transfer Functions (ITFs) (i.e., graded floodlamp exposures that are used to linearize and normalize the camera response). A technique for precisely registering IUE images which uses a cross correlation of the fixed pattern that exists in all raw IUE images is described.
Accurate maser positions for MALT-45
NASA Astrophysics Data System (ADS)
Jordan, Christopher; Bains, Indra; Voronkov, Maxim; Lo, Nadia; Jones, Paul; Muller, Erik; Cunningham, Maria; Burton, Michael; Brooks, Kate; Green, James; Fuller, Gary; Barnes, Peter; Ellingsen, Simon; Urquhart, James; Morgan, Larry; Rowell, Gavin; Walsh, Andrew; Loenen, Edo; Baan, Willem; Hill, Tracey; Purcell, Cormac; Breen, Shari; Peretto, Nicolas; Jackson, James; Lowe, Vicki; Longmore, Steven
2013-10-01
MALT-45 is an untargeted survey, mapping the Galactic plane in CS (1-0), Class I methanol masers, SiO masers and thermal emission, and high frequency continuum emission. After obtaining images from the survey, a number of masers were detected, but without accurate positions. This project seeks to resolve each maser and its environment, with the ultimate goal of placing the Class I methanol maser into a timeline of high mass star formation.
Average Weighted Receiving Time of Weighted Tetrahedron Koch Networks
NASA Astrophysics Data System (ADS)
Dai, Meifeng; Zhang, Danping; Ye, Dandan; Zhang, Cheng; Li, Lei
2015-07-01
We introduce weighted tetrahedron Koch networks with infinite weight factors, which are generalization of finite ones. The term of weighted time is firstly defined in this literature. The mean weighted first-passing time (MWFPT) and the average weighted receiving time (AWRT) are defined by weighted time accordingly. We study the AWRT with weight-dependent walk. Results show that the AWRT for a nontrivial weight factor sequence grows sublinearly with the network order. To investigate the reason of sublinearity, the average receiving time (ART) for four cases are discussed.
Weighted Uncertainty Relations
NASA Astrophysics Data System (ADS)
Xiao, Yunlong; Jing, Naihuan; Li-Jost, Xianqing; Fei, Shao-Ming
2016-03-01
Recently, Maccone and Pati have given two stronger uncertainty relations based on the sum of variances and one of them is nontrivial when the quantum state is not an eigenstate of the sum of the observables. We derive a family of weighted uncertainty relations to provide an optimal lower bound for all situations and remove the restriction on the quantum state. Generalization to multi-observable cases is also given and an optimal lower bound for the weighted sum of the variances is obtained in general quantum situation.
Weighted Uncertainty Relations
Xiao, Yunlong; Jing, Naihuan; Li-Jost, Xianqing; Fei, Shao-Ming
2016-01-01
Recently, Maccone and Pati have given two stronger uncertainty relations based on the sum of variances and one of them is nontrivial when the quantum state is not an eigenstate of the sum of the observables. We derive a family of weighted uncertainty relations to provide an optimal lower bound for all situations and remove the restriction on the quantum state. Generalization to multi-observable cases is also given and an optimal lower bound for the weighted sum of the variances is obtained in general quantum situation. PMID:26984295
Accurate phase-shift velocimetry in rock.
Shukla, Matsyendra Nath; Vallatos, Antoine; Phoenix, Vernon R; Holmes, William M
2016-06-01
Spatially resolved Pulsed Field Gradient (PFG) velocimetry techniques can provide precious information concerning flow through opaque systems, including rocks. This velocimetry data is used to enhance flow models in a wide range of systems, from oil behaviour in reservoir rocks to contaminant transport in aquifers. Phase-shift velocimetry is the fastest way to produce velocity maps but critical issues have been reported when studying flow through rocks and porous media, leading to inaccurate results. Combining PFG measurements for flow through Bentheimer sandstone with simulations, we demonstrate that asymmetries in the molecular displacement distributions within each voxel are the main source of phase-shift velocimetry errors. We show that when flow-related average molecular displacements are negligible compared to self-diffusion ones, symmetric displacement distributions can be obtained while phase measurement noise is minimised. We elaborate a complete method for the production of accurate phase-shift velocimetry maps in rocks and low porosity media and demonstrate its validity for a range of flow rates. This development of accurate phase-shift velocimetry now enables more rapid and accurate velocity analysis, potentially helping to inform both industrial applications and theoretical models. PMID:27111139
Accurate Molecular Polarizabilities Based on Continuum Electrostatics
Truchon, Jean-François; Nicholls, Anthony; Iftimie, Radu I.; Roux, Benoît; Bayly, Christopher I.
2013-01-01
A novel approach for representing the intramolecular polarizability as a continuum dielectric is introduced to account for molecular electronic polarization. It is shown, using a finite-difference solution to the Poisson equation, that the Electronic Polarization from Internal Continuum (EPIC) model yields accurate gas-phase molecular polarizability tensors for a test set of 98 challenging molecules composed of heteroaromatics, alkanes and diatomics. The electronic polarization originates from a high intramolecular dielectric that produces polarizabilities consistent with B3LYP/aug-cc-pVTZ and experimental values when surrounded by vacuum dielectric. In contrast to other approaches to model electronic polarization, this simple model avoids the polarizability catastrophe and accurately calculates molecular anisotropy with the use of very few fitted parameters and without resorting to auxiliary sites or anisotropic atomic centers. On average, the unsigned error in the average polarizability and anisotropy compared to B3LYP are 2% and 5%, respectively. The correlation between the polarizability components from B3LYP and this approach lead to a R2 of 0.990 and a slope of 0.999. Even the F2 anisotropy, shown to be a difficult case for existing polarizability models, can be reproduced within 2% error. In addition to providing new parameters for a rapid method directly applicable to the calculation of polarizabilities, this work extends the widely used Poisson equation to areas where accurate molecular polarizabilities matter. PMID:23646034
Accurate phase-shift velocimetry in rock
NASA Astrophysics Data System (ADS)
Shukla, Matsyendra Nath; Vallatos, Antoine; Phoenix, Vernon R.; Holmes, William M.
2016-06-01
Spatially resolved Pulsed Field Gradient (PFG) velocimetry techniques can provide precious information concerning flow through opaque systems, including rocks. This velocimetry data is used to enhance flow models in a wide range of systems, from oil behaviour in reservoir rocks to contaminant transport in aquifers. Phase-shift velocimetry is the fastest way to produce velocity maps but critical issues have been reported when studying flow through rocks and porous media, leading to inaccurate results. Combining PFG measurements for flow through Bentheimer sandstone with simulations, we demonstrate that asymmetries in the molecular displacement distributions within each voxel are the main source of phase-shift velocimetry errors. We show that when flow-related average molecular displacements are negligible compared to self-diffusion ones, symmetric displacement distributions can be obtained while phase measurement noise is minimised. We elaborate a complete method for the production of accurate phase-shift velocimetry maps in rocks and low porosity media and demonstrate its validity for a range of flow rates. This development of accurate phase-shift velocimetry now enables more rapid and accurate velocity analysis, potentially helping to inform both industrial applications and theoretical models.
High Frequency QRS ECG Accurately Detects Cardiomyopathy
NASA Technical Reports Server (NTRS)
Schlegel, Todd T.; Arenare, Brian; Poulin, Gregory; Moser, Daniel R.; Delgado, Reynolds
2005-01-01
High frequency (HF, 150-250 Hz) analysis over the entire QRS interval of the ECG is more sensitive than conventional ECG for detecting myocardial ischemia. However, the accuracy of HF QRS ECG for detecting cardiomyopathy is unknown. We obtained simultaneous resting conventional and HF QRS 12-lead ECGs in 66 patients with cardiomyopathy (EF = 23.2 plus or minus 6.l%, mean plus or minus SD) and in 66 age- and gender-matched healthy controls using PC-based ECG software recently developed at NASA. The single most accurate ECG parameter for detecting cardiomyopathy was an HF QRS morphological score that takes into consideration the total number and severity of reduced amplitude zones (RAZs) present plus the clustering of RAZs together in contiguous leads. This RAZ score had an area under the receiver operator curve (ROC) of 0.91, and was 88% sensitive, 82% specific and 85% accurate for identifying cardiomyopathy at optimum score cut-off of 140 points. Although conventional ECG parameters such as the QRS and QTc intervals were also significantly longer in patients than controls (P less than 0.001, BBBs excluded), these conventional parameters were less accurate (area under the ROC = 0.77 and 0.77, respectively) than HF QRS morphological parameters for identifying underlying cardiomyopathy. The total amplitude of the HF QRS complexes, as measured by summed root mean square voltages (RMSVs), also differed between patients and controls (33.8 plus or minus 11.5 vs. 41.5 plus or minus 13.6 mV, respectively, P less than 0.003), but this parameter was even less accurate in distinguishing the two groups (area under ROC = 0.67) than the HF QRS morphologic and conventional ECG parameters. Diagnostic accuracy was optimal (86%) when the RAZ score from the HF QRS ECG and the QTc interval from the conventional ECG were used simultaneously with cut-offs of greater than or equal to 40 points and greater than or equal to 445 ms, respectively. In conclusion 12-lead HF QRS ECG employing
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... Therapy and Weight Management (Nemours Foundation) Also in Spanish Weight Loss: Ready to Change Your Habits? (Mayo Foundation for Medical Education and Research) Weight-Loss and Nutrition Myths (National ...
Weight and Diabetes (For Parents)
... Things to Know About Zika & Pregnancy Weight and Diabetes KidsHealth > For Parents > Weight and Diabetes Print A ... or type 2 diabetes. Weight and Type 1 Diabetes Undiagnosed or untreated, type 1 diabetes can make ...
Brief report: Weight dissatisfaction, weight status, and weight loss in Mexican-American children
Technology Transfer Automated Retrieval System (TEKTRAN)
The study objectives were to assess the association between weight dissatisfaction, weight status, and weight loss in Mexican-American children participating in a weight management program. Participants included 265 Mexican American children recruited for a school-based weight management program. Al...
Implicit Bias about Weight and Weight Loss Treatment Outcomes
Carels, Robert A; Hinman, Nova G; Hoffmann, Debra A; Burmeister, Jacob M; Borushok, Jessica E.; Marx, Jenna M; Ashrafioun, Lisham
2014-01-01
Objectives The goal of the current study was to examine the impact of a weight loss intervention on implicit bias toward weight, as well as the relationship among implicit bias, weight loss behaviors, and weight loss outcomes. Additionally, of interest was the relationship among these variables when implicit weight bias was measured with a novel assessment that portrays individuals who are thin and obese engaged in both stereotypical and nonstereotypical health-related behaviors. Methods Implicit weight bias (stereotype consistent and stereotype inconsistent), binge eating, self-monitoring, and body weight were assessed among weight loss participants at baseline and post-treatment (N=44) participating in two weight loss programs. Results Stereotype consistent bias significantly decreased from baseline to post-treatment. Greater baseline stereotype consistent bias was associated with lower binge eating and greater self-monitoring. Greater post-treatment stereotype consistent bias was associated with greater percent weight loss. Stereotype inconsistent bias did not change from baseline to post-treatment and was generally unrelated to outcomes. Conclusion Weight loss treatment may reduce implicit bias toward overweight individuals among weight loss participants. Higher post-treatment stereotype consistent bias was associated with a higher percent weight loss, possibly suggesting that losing weight may serve to maintain implicit weight bias. Alternatively, great implicit weight bias may identify individuals motivated to make changes necessary for weight loss. PMID:25261809
ERIC Educational Resources Information Center
Nutter, June
1995-01-01
Secondary level physical education teachers can have their students use math concepts while working out on the weight-room equipment. The article explains how students can reinforce math skills while weightlifting by estimating their strength, estimating their power, or calculating other formulas. (SM)
Analytical Fuselage and Wing Weight Estimation of Transport Aircraft
NASA Technical Reports Server (NTRS)
Chambers, Mark C.; Ardema, Mark D.; Patron, Anthony P.; Hahn, Andrew S.; Miura, Hirokazu; Moore, Mark D.
1996-01-01
A method of estimating the load-bearing fuselage weight and wing weight of transport aircraft based on fundamental structural principles has been developed. This method of weight estimation represents a compromise between the rapid assessment of component weight using empirical methods based on actual weights of existing aircraft, and detailed, but time-consuming, analysis using the finite element method. The method was applied to eight existing subsonic transports for validation and correlation. Integration of the resulting computer program, PDCYL, has been made into the weights-calculating module of the AirCraft SYNThesis (ACSYNT) computer program. ACSYNT has traditionally used only empirical weight estimation methods; PDCYL adds to ACSYNT a rapid, accurate means of assessing the fuselage and wing weights of unconventional aircraft. PDCYL also allows flexibility in the choice of structural concept, as well as a direct means of determining the impact of advanced materials on structural weight. Using statistical analysis techniques, relations between the load-bearing fuselage and wing weights calculated by PDCYL and corresponding actual weights were determined.
Accurately Mapping M31's Microlensing Population
NASA Astrophysics Data System (ADS)
Crotts, Arlin
2004-07-01
We propose to augment an existing microlensing survey of M31 with source identifications provided by a modest amount of ACS {and WFPC2 parallel} observations to yield an accurate measurement of the masses responsible for microlensing in M31, and presumably much of its dark matter. The main benefit of these data is the determination of the physical {or "einstein"} timescale of each microlensing event, rather than an effective {"FWHM"} timescale, allowing masses to be determined more than twice as accurately as without HST data. The einstein timescale is the ratio of the lensing cross-sectional radius and relative velocities. Velocities are known from kinematics, and the cross-section is directly proportional to the {unknown} lensing mass. We cannot easily measure these quantities without knowing the amplification, hence the baseline magnitude, which requires the resolution of HST to find the source star. This makes a crucial difference because M31 lens m ass determinations can be more accurate than those towards the Magellanic Clouds through our Galaxy's halo {for the same number of microlensing events} due to the better constrained geometry in the M31 microlensing situation. Furthermore, our larger survey, just completed, should yield at least 100 M31 microlensing events, more than any Magellanic survey. A small amount of ACS+WFPC2 imaging will deliver the potential of this large database {about 350 nights}. For the whole survey {and a delta-function mass distribution} the mass error should approach only about 15%, or about 6% error in slope for a power-law distribution. These results will better allow us to pinpoint the lens halo fraction, and the shape of the halo lens spatial distribution, and allow generalization/comparison of the nature of halo dark matter in spiral galaxies. In addition, we will be able to establish the baseline magnitude for about 50, 000 variable stars, as well as measure an unprecedentedly deta iled color-magnitude diagram and luminosity
Accurate measurement of unsteady state fluid temperature
NASA Astrophysics Data System (ADS)
Jaremkiewicz, Magdalena
2016-07-01
In this paper, two accurate methods for determining the transient fluid temperature were presented. Measurements were conducted for boiling water since its temperature is known. At the beginning the thermometers are at the ambient temperature and next they are immediately immersed into saturated water. The measurements were carried out with two thermometers of different construction but with the same housing outer diameter equal to 15 mm. One of them is a K-type industrial thermometer widely available commercially. The temperature indicated by the thermometer was corrected considering the thermometers as the first or second order inertia devices. The new design of a thermometer was proposed and also used to measure the temperature of boiling water. Its characteristic feature is a cylinder-shaped housing with the sheath thermocouple located in its center. The temperature of the fluid was determined based on measurements taken in the axis of the solid cylindrical element (housing) using the inverse space marching method. Measurements of the transient temperature of the air flowing through the wind tunnel using the same thermometers were also carried out. The proposed measurement technique provides more accurate results compared with measurements using industrial thermometers in conjunction with simple temperature correction using the inertial thermometer model of the first or second order. By comparing the results, it was demonstrated that the new thermometer allows obtaining the fluid temperature much faster and with higher accuracy in comparison to the industrial thermometer. Accurate measurements of the fast changing fluid temperature are possible due to the low inertia thermometer and fast space marching method applied for solving the inverse heat conduction problem.
Accurate upwind methods for the Euler equations
NASA Technical Reports Server (NTRS)
Huynh, Hung T.
1993-01-01
A new class of piecewise linear methods for the numerical solution of the one-dimensional Euler equations of gas dynamics is presented. These methods are uniformly second-order accurate, and can be considered as extensions of Godunov's scheme. With an appropriate definition of monotonicity preservation for the case of linear convection, it can be shown that they preserve monotonicity. Similar to Van Leer's MUSCL scheme, they consist of two key steps: a reconstruction step followed by an upwind step. For the reconstruction step, a monotonicity constraint that preserves uniform second-order accuracy is introduced. Computational efficiency is enhanced by devising a criterion that detects the 'smooth' part of the data where the constraint is redundant. The concept and coding of the constraint are simplified by the use of the median function. A slope steepening technique, which has no effect at smooth regions and can resolve a contact discontinuity in four cells, is described. As for the upwind step, existing and new methods are applied in a manner slightly different from those in the literature. These methods are derived by approximating the Euler equations via linearization and diagonalization. At a 'smooth' interface, Harten, Lax, and Van Leer's one intermediate state model is employed. A modification for this model that can resolve contact discontinuities is presented. Near a discontinuity, either this modified model or a more accurate one, namely, Roe's flux-difference splitting. is used. The current presentation of Roe's method, via the conceptually simple flux-vector splitting, not only establishes a connection between the two splittings, but also leads to an admissibility correction with no conditional statement, and an efficient approximation to Osher's approximate Riemann solver. These reconstruction and upwind steps result in schemes that are uniformly second-order accurate and economical at smooth regions, and yield high resolution at discontinuities.
Ideal Weight and Weight Satisfaction: Association With Health Practices
Ardern, Chris I.; Church, Timothy S.; Hebert, James R.; Sui, Xuemei; Blair, Steven N.
2009-01-01
Evidence suggests that individuals have become more tolerant of higher body weights over time. To investigate this issue further, the authors examined cross-sectional associations among ideal weight, examination year, and obesity as well as the association of ideal weight and body weight satisfaction with health practices among 15,221 men and 4,126 women in the United States. Participants in 1987 reported higher ideal weights than participants in 2001, an effect particularly pronounced from 1987 to 2001 for younger and obese men (85.5 kg to 94.9 kg) and women (62.2 kg to 70.5 kg). For a given body mass index, higher ideal body weights were associated with greater weight satisfaction but lower intentions to lose weight. Body weight satisfaction was subsequently associated with greater walking/jogging, better diet, and lower lifetime weight loss but with less intention to change physical activity and diet or lose weight (P < 0.01). Conversely, body mass index was negatively associated with weight satisfaction (P < 0.01) and was associated with less walking/jogging, poorer diet, and greater lifetime weight loss but with greater intention to change physical activity and diet or lose weight. Although the health implications of these findings are somewhat unclear, increased weight satisfaction, in conjunction with increases in societal overweight/obesity, may result in decreased motivation to lose weight and/or adopt healthier lifestyle behaviors. PMID:19546153
The first accurate description of an aurora
NASA Astrophysics Data System (ADS)
Schröder, Wilfried
2006-12-01
As technology has advanced, the scientific study of auroral phenomena has increased by leaps and bounds. A look back at the earliest descriptions of aurorae offers an interesting look into how medieval scholars viewed the subjects that we study.Although there are earlier fragmentary references in the literature, the first accurate description of the aurora borealis appears to be that published by the German Catholic scholar Konrad von Megenberg (1309-1374) in his book Das Buch der Natur (The Book of Nature). The book was written between 1349 and 1350.
Are Kohn-Sham conductances accurate?
Mera, H; Niquet, Y M
2010-11-19
We use Fermi-liquid relations to address the accuracy of conductances calculated from the single-particle states of exact Kohn-Sham (KS) density functional theory. We demonstrate a systematic failure of this procedure for the calculation of the conductance, and show how it originates from the lack of renormalization in the KS spectral function. In certain limits this failure can lead to a large overestimation of the true conductance. We also show, however, that the KS conductances can be accurate for single-channel molecular junctions and systems where direct Coulomb interactions are strongly dominant. PMID:21231333
Accurate density functional thermochemistry for larger molecules.
Raghavachari, K.; Stefanov, B. B.; Curtiss, L. A.; Lucent Tech.
1997-06-20
Density functional methods are combined with isodesmic bond separation reaction energies to yield accurate thermochemistry for larger molecules. Seven different density functionals are assessed for the evaluation of heats of formation, Delta H 0 (298 K), for a test set of 40 molecules composed of H, C, O and N. The use of bond separation energies results in a dramatic improvement in the accuracy of all the density functionals. The B3-LYP functional has the smallest mean absolute deviation from experiment (1.5 kcal mol/f).
New law requires 'medically accurate' lesson plans.
1999-09-17
The California Legislature has passed a bill requiring all textbooks and materials used to teach about AIDS be medically accurate and objective. Statements made within the curriculum must be supported by research conducted in compliance with scientific methods, and published in peer-reviewed journals. Some of the current lesson plans were found to contain scientifically unsupported and biased information. In addition, the bill requires material to be "free of racial, ethnic, or gender biases." The legislation is supported by a wide range of interests, but opposed by the California Right to Life Education Fund, because they believe it discredits abstinence-only material. PMID:11366835
Accurate basis set truncation for wavefunction embedding
NASA Astrophysics Data System (ADS)
Barnes, Taylor A.; Goodpaster, Jason D.; Manby, Frederick R.; Miller, Thomas F.
2013-07-01
Density functional theory (DFT) provides a formally exact framework for performing embedded subsystem electronic structure calculations, including DFT-in-DFT and wavefunction theory-in-DFT descriptions. In the interest of efficiency, it is desirable to truncate the atomic orbital basis set in which the subsystem calculation is performed, thus avoiding high-order scaling with respect to the size of the MO virtual space. In this study, we extend a recently introduced projection-based embedding method [F. R. Manby, M. Stella, J. D. Goodpaster, and T. F. Miller III, J. Chem. Theory Comput. 8, 2564 (2012)], 10.1021/ct300544e to allow for the systematic and accurate truncation of the embedded subsystem basis set. The approach is applied to both covalently and non-covalently bound test cases, including water clusters and polypeptide chains, and it is demonstrated that errors associated with basis set truncation are controllable to well within chemical accuracy. Furthermore, we show that this approach allows for switching between accurate projection-based embedding and DFT embedding with approximate kinetic energy (KE) functionals; in this sense, the approach provides a means of systematically improving upon the use of approximate KE functionals in DFT embedding.
Fast and accurate propagation of coherent light
Lewis, R. D.; Beylkin, G.; Monzón, L.
2013-01-01
We describe a fast algorithm to propagate, for any user-specified accuracy, a time-harmonic electromagnetic field between two parallel planes separated by a linear, isotropic and homogeneous medium. The analytical formulation of this problem (ca 1897) requires the evaluation of the so-called Rayleigh–Sommerfeld integral. If the distance between the planes is small, this integral can be accurately evaluated in the Fourier domain; if the distance is very large, it can be accurately approximated by asymptotic methods. In the large intermediate region of practical interest, where the oscillatory Rayleigh–Sommerfeld kernel must be applied directly, current numerical methods can be highly inaccurate without indicating this fact to the user. In our approach, for any user-specified accuracy ϵ>0, we approximate the kernel by a short sum of Gaussians with complex-valued exponents, and then efficiently apply the result to the input data using the unequally spaced fast Fourier transform. The resulting algorithm has computational complexity , where we evaluate the solution on an N×N grid of output points given an M×M grid of input samples. Our algorithm maintains its accuracy throughout the computational domain. PMID:24204184
How Accurately can we Calculate Thermal Systems?
Cullen, D; Blomquist, R N; Dean, C; Heinrichs, D; Kalugin, M A; Lee, M; Lee, Y; MacFarlan, R; Nagaya, Y; Trkov, A
2004-04-20
I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it would be more precise to say that I would like to determine the spread in answers that we obtain from a variety of code packages. This spread should serve as an excellent indicator of how accurately we can really model and calculate such systems today. Hopefully, eventually this will lead to improvements in both our codes and the thermal scattering models that they use in the future. In order to accomplish this I propose a number of extremely simple systems that involve thermal neutron scattering that can be easily modeled and calculated by a variety of neutron transport codes. These are theoretical systems designed to emphasize the effects of thermal scattering, since that is what we are interested in studying. I have attempted to keep these systems very simple, and yet at the same time they include most, if not all, of the important thermal scattering effects encountered in a large, water-moderated, uranium fueled thermal system, i.e., our typical thermal reactors.
Accurate shear measurement with faint sources
Zhang, Jun; Foucaud, Sebastien; Luo, Wentao E-mail: walt@shao.ac.cn
2015-01-01
For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be measured accurately in Fourier space in the presence of background noise and finite pixel size, without assumptions on the morphologies of galaxy and PSF. The remaining major source of error is source Poisson noise, due to the finiteness of source photon number. This problem is particularly important for faint galaxies in space-based weak lensing measurements, and for ground-based images of short exposure times. In this work, we propose a simple and rigorous way of removing the shear bias from the source Poisson noise. Our noise treatment can be generalized for images made of multiple exposures through MultiDrizzle. This is demonstrated with the SDSS and COSMOS/ACS data. With a large ensemble of mock galaxy images of unrestricted morphologies, we show that our shear measurement method can achieve sub-percent level accuracy even for images of signal-to-noise ratio less than 5 in general, making it the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.
Accurate pose estimation for forensic identification
NASA Astrophysics Data System (ADS)
Merckx, Gert; Hermans, Jeroen; Vandermeulen, Dirk
2010-04-01
In forensic authentication, one aims to identify the perpetrator among a series of suspects or distractors. A fundamental problem in any recognition system that aims for identification of subjects in a natural scene is the lack of constrains on viewing and imaging conditions. In forensic applications, identification proves even more challenging, since most surveillance footage is of abysmal quality. In this context, robust methods for pose estimation are paramount. In this paper we will therefore present a new pose estimation strategy for very low quality footage. Our approach uses 3D-2D registration of a textured 3D face model with the surveillance image to obtain accurate far field pose alignment. Starting from an inaccurate initial estimate, the technique uses novel similarity measures based on the monogenic signal to guide a pose optimization process. We will illustrate the descriptive strength of the introduced similarity measures by using them directly as a recognition metric. Through validation, using both real and synthetic surveillance footage, our pose estimation method is shown to be accurate, and robust to lighting changes and image degradation.
Accurate determination of characteristic relative permeability curves
NASA Astrophysics Data System (ADS)
Krause, Michael H.; Benson, Sally M.
2015-09-01
A recently developed technique to accurately characterize sub-core scale heterogeneity is applied to investigate the factors responsible for flowrate-dependent effective relative permeability curves measured on core samples in the laboratory. The dependency of laboratory measured relative permeability on flowrate has long been both supported and challenged by a number of investigators. Studies have shown that this apparent flowrate dependency is a result of both sub-core scale heterogeneity and outlet boundary effects. However this has only been demonstrated numerically for highly simplified models of porous media. In this paper, flowrate dependency of effective relative permeability is demonstrated using two rock cores, a Berea Sandstone and a heterogeneous sandstone from the Otway Basin Pilot Project in Australia. Numerical simulations of steady-state coreflooding experiments are conducted at a number of injection rates using a single set of input characteristic relative permeability curves. Effective relative permeability is then calculated from the simulation data using standard interpretation methods for calculating relative permeability from steady-state tests. Results show that simplified approaches may be used to determine flowrate-independent characteristic relative permeability provided flow rate is sufficiently high, and the core heterogeneity is relatively low. It is also shown that characteristic relative permeability can be determined at any typical flowrate, and even for geologically complex models, when using accurate three-dimensional models.
Gain weighted eigenspace assignment
NASA Technical Reports Server (NTRS)
Davidson, John B.; Andrisani, Dominick, II
1994-01-01
This report presents the development of the gain weighted eigenspace assignment methodology. This provides a designer with a systematic methodology for trading off eigenvector placement versus gain magnitudes, while still maintaining desired closed-loop eigenvalue locations. This is accomplished by forming a cost function composed of a scalar measure of error between desired and achievable eigenvectors and a scalar measure of gain magnitude, determining analytical expressions for the gradients, and solving for the optimal solution by numerical iteration. For this development the scalar measure of gain magnitude is chosen to be a weighted sum of the squares of all the individual elements of the feedback gain matrix. An example is presented to demonstrate the method. In this example, solutions yielding achievable eigenvectors close to the desired eigenvectors are obtained with significant reductions in gain magnitude compared to a solution obtained using a previously developed eigenspace (eigenstructure) assignment method.
Cheney, M.C.
1997-12-31
The cost of energy for renewables has gained greater significance in recent years due to the drop in price in some competing energy sources, particularly natural gas. In pursuit of lower manufacturing costs for wind turbine systems, work was conducted to explore an innovative rotor designed to reduce weight and cost over conventional rotor systems. Trade-off studies were conducted to measure the influence of number of blades, stiffness, and manufacturing method on COE. The study showed that increasing number of blades at constant solidity significantly reduced rotor weight and that manufacturing the blades using pultrusion technology produced the lowest cost per pound. Under contracts with the National Renewable Energy Laboratory and the California Energy Commission, a 400 kW (33m diameter) turbine was designed employing this technology. The project included tests of an 80 kW (15.5m diameter) dynamically scaled rotor which demonstrated the viability of the design.
Accurate Wind Characterization in Complex Terrain Using the Immersed Boundary Method
Lundquist, K A; Chow, F K; Lundquist, J K; Kosovic, B
2009-09-30
This paper describes an immersed boundary method (IBM) that facilitates the explicit resolution of complex terrain within the Weather Research and Forecasting (WRF) model. Two different interpolation methods, trilinear and inverse distance weighting, are used at the core of the IBM algorithm. Functional aspects of the algorithm's implementation and the accuracy of results are considered. Simulations of flow over a three-dimensional hill with shallow terrain slopes are preformed with both WRF's native terrain-following coordinate and with both IB methods. Comparisons of flow fields from the three simulations show excellent agreement, indicating that both IB methods produce accurate results. However, when ease of implementation is considered, inverse distance weighting is superior. Furthermore, inverse distance weighting is shown to be more adept at handling highly complex urban terrain, where the trilinear interpolation algorithm breaks down. This capability is demonstrated by using the inverse distance weighting core of the IBM to model atmospheric flow in downtown Oklahoma City.
NASA Astrophysics Data System (ADS)
Serrano, M. Ángeles; Boguñá, Marián
2005-06-01
The configuration model is one of the most successful models for generating uncorrelated random networks. We analyze its behavior when the expected degree sequence follows a power law with exponent smaller than two. In this situation, the resulting network can be viewed as a weighted network with non trivial correlations between strength and degree. Our results are tested against large scale numerical simulations, finding excellent agreement.
NASA Astrophysics Data System (ADS)
Catura, R. C.; Vieira, J. R.
1985-09-01
Light weight mirror blanks were fabricated by dip-brazing a core of low mass aluminum foam material to thin face sheets of solid aluminum. The blanks weigh 40% of an equivalent size solid mirror and were diamond turned to provide reflective surfaces. Optical interferometry was used to assess their dimensional stability over 7 months. No changes in flatness are observed (to the sensitivity of the measurements of a half wavelength of red light).
(Bessel-) weighted asymmetries
Bernhard Musch, Alexey Prokudin
2011-11-01
Semi-inclusive deep inelastic scattering experiments allow us to probe the motion of quarks inside the proton in terms of so-called transverse momentum dependent parton distribution functions (TMD PDFs), but the information is convoluted with fragmentation functions (TMD FFs) and soft factors. It has long been known that weighting the measured event counts with powers of the hadron momentum before forming angular asymmetries de-convolutes TMD PDFs and TMD FFs in an elegant way, but this also entails an undesirable sensitivity to high momentum contributions. Using Bessel functions as weights, we find a natural generalization of weighted asymmetries that preserves the de-convolution property and features soft-factor cancellation, yet allows us to be less sensitive to high transverse momenta. The formalism also relates to TMD quantities studied in lattice QCD. We briefly show preliminary lattice results from an exploratory calculation of the Boer-Mulders shift using lattices generated by the MILC and LHP collaborations at a pion mass of 500 MeV.
Accurate FDTD modelling for dispersive media using rational function and particle swarm optimisation
NASA Astrophysics Data System (ADS)
Chung, Haejun; Ha, Sang-Gyu; Choi, Jaehoon; Jung, Kyung-Young
2015-07-01
This article presents an accurate finite-difference time domain (FDTD) dispersive modelling suitable for complex dispersive media. A quadratic complex rational function (QCRF) is used to characterise their dispersive relations. To obtain accurate coefficients of QCRF, in this work, we use an analytical approach and a particle swarm optimisation (PSO) simultaneously. In specific, an analytical approach is used to obtain the QCRF matrix-solving equation and PSO is applied to adjust a weighting function of this equation. Numerical examples are used to illustrate the validity of the proposed FDTD dispersion model.
Accurate Thermal Stresses for Beams: Normal Stress
NASA Technical Reports Server (NTRS)
Johnson, Theodore F.; Pilkey, Walter D.
2003-01-01
Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.
Accurate Thermal Stresses for Beams: Normal Stress
NASA Technical Reports Server (NTRS)
Johnson, Theodore F.; Pilkey, Walter D.
2002-01-01
Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.
Highly accurate articulated coordinate measuring machine
Bieg, Lothar F.; Jokiel, Jr., Bernhard; Ensz, Mark T.; Watson, Robert D.
2003-12-30
Disclosed is a highly accurate articulated coordinate measuring machine, comprising a revolute joint, comprising a circular encoder wheel, having an axis of rotation; a plurality of marks disposed around at least a portion of the circumference of the encoder wheel; bearing means for supporting the encoder wheel, while permitting free rotation of the encoder wheel about the wheel's axis of rotation; and a sensor, rigidly attached to the bearing means, for detecting the motion of at least some of the marks as the encoder wheel rotates; a probe arm, having a proximal end rigidly attached to the encoder wheel, and having a distal end with a probe tip attached thereto; and coordinate processing means, operatively connected to the sensor, for converting the output of the sensor into a set of cylindrical coordinates representing the position of the probe tip relative to a reference cylindrical coordinate system.
Practical aspects of spatially high accurate methods
NASA Technical Reports Server (NTRS)
Godfrey, Andrew G.; Mitchell, Curtis R.; Walters, Robert W.
1992-01-01
The computational qualities of high order spatially accurate methods for the finite volume solution of the Euler equations are presented. Two dimensional essentially non-oscillatory (ENO), k-exact, and 'dimension by dimension' ENO reconstruction operators are discussed and compared in terms of reconstruction and solution accuracy, computational cost and oscillatory behavior in supersonic flows with shocks. Inherent steady state convergence difficulties are demonstrated for adaptive stencil algorithms. An exact solution to the heat equation is used to determine reconstruction error, and the computational intensity is reflected in operation counts. Standard MUSCL differencing is included for comparison. Numerical experiments presented include the Ringleb flow for numerical accuracy and a shock reflection problem. A vortex-shock interaction demonstrates the ability of the ENO scheme to excel in simulating unsteady high-frequency flow physics.
The thermodynamic cost of accurate sensory adaptation
NASA Astrophysics Data System (ADS)
Tu, Yuhai
2015-03-01
Living organisms need to obtain and process environment information accurately in order to make decisions critical for their survival. Much progress have been made in identifying key components responsible for various biological functions, however, major challenges remain to understand system-level behaviors from the molecular-level knowledge of biology and to unravel possible physical principles for the underlying biochemical circuits. In this talk, we will present some recent works in understanding the chemical sensory system of E. coli by combining theoretical approaches with quantitative experiments. We focus on addressing the questions on how cells process chemical information and adapt to varying environment, and what are the thermodynamic limits of key regulatory functions, such as adaptation.
Accurate numerical solutions of conservative nonlinear oscillators
NASA Astrophysics Data System (ADS)
Khan, Najeeb Alam; Nasir Uddin, Khan; Nadeem Alam, Khan
2014-12-01
The objective of this paper is to present an investigation to analyze the vibration of a conservative nonlinear oscillator in the form u" + lambda u + u^(2n-1) + (1 + epsilon^2 u^(4m))^(1/2) = 0 for any arbitrary power of n and m. This method converts the differential equation to sets of algebraic equations and solve numerically. We have presented for three different cases: a higher order Duffing equation, an equation with irrational restoring force and a plasma physics equation. It is also found that the method is valid for any arbitrary order of n and m. Comparisons have been made with the results found in the literature the method gives accurate results.
Accurate Telescope Mount Positioning with MEMS Accelerometers
NASA Astrophysics Data System (ADS)
Mészáros, L.; Jaskó, A.; Pál, A.; Csépány, G.
2014-08-01
This paper describes the advantages and challenges of applying microelectromechanical accelerometer systems (MEMS accelerometers) in order to attain precise, accurate, and stateless positioning of telescope mounts. This provides a completely independent method from other forms of electronic, optical, mechanical or magnetic feedback or real-time astrometry. Our goal is to reach the subarcminute range which is considerably smaller than the field-of-view of conventional imaging telescope systems. Here we present how this subarcminute accuracy can be achieved with very cheap MEMS sensors and we also detail how our procedures can be extended in order to attain even finer measurements. In addition, our paper discusses how can a complete system design be implemented in order to be a part of a telescope control system.
Accurate metacognition for visual sensory memory representations.
Vandenbroucke, Annelinde R E; Sligte, Ilja G; Barrett, Adam B; Seth, Anil K; Fahrenfort, Johannes J; Lamme, Victor A F
2014-04-01
The capacity to attend to multiple objects in the visual field is limited. However, introspectively, people feel that they see the whole visual world at once. Some scholars suggest that this introspective feeling is based on short-lived sensory memory representations, whereas others argue that the feeling of seeing more than can be attended to is illusory. Here, we investigated this phenomenon by combining objective memory performance with subjective confidence ratings during a change-detection task. This allowed us to compute a measure of metacognition--the degree of knowledge that subjects have about the correctness of their decisions--for different stages of memory. We show that subjects store more objects in sensory memory than they can attend to but, at the same time, have similar metacognition for sensory memory and working memory representations. This suggests that these subjective impressions are not an illusion but accurate reflections of the richness of visual perception. PMID:24549293
Apparatus for accurately measuring high temperatures
Smith, Douglas D.
1985-01-01
The present invention is a thermometer used for measuring furnace temperaes in the range of about 1800.degree. to 2700.degree. C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.
Apparatus for accurately measuring high temperatures
Smith, D.D.
The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.
Toward Accurate and Quantitative Comparative Metagenomics.
Nayfach, Stephen; Pollard, Katherine S
2016-08-25
Shotgun metagenomics and computational analysis are used to compare the taxonomic and functional profiles of microbial communities. Leveraging this approach to understand roles of microbes in human biology and other environments requires quantitative data summaries whose values are comparable across samples and studies. Comparability is currently hampered by the use of abundance statistics that do not estimate a meaningful parameter of the microbial community and biases introduced by experimental protocols and data-cleaning approaches. Addressing these challenges, along with improving study design, data access, metadata standardization, and analysis tools, will enable accurate comparative metagenomics. We envision a future in which microbiome studies are replicable and new metagenomes are easily and rapidly integrated with existing data. Only then can the potential of metagenomics for predictive ecological modeling, well-powered association studies, and effective microbiome medicine be fully realized. PMID:27565341
The importance of accurate atmospheric modeling
NASA Astrophysics Data System (ADS)
Payne, Dylan; Schroeder, John; Liang, Pang
2014-11-01
This paper will focus on the effect of atmospheric conditions on EO sensor performance using computer models. We have shown the importance of accurately modeling atmospheric effects for predicting the performance of an EO sensor. A simple example will demonstrated how real conditions for several sites in China will significantly impact on image correction, hyperspectral imaging, and remote sensing. The current state-of-the-art model for computing atmospheric transmission and radiance is, MODTRAN® 5, developed by the US Air Force Research Laboratory and Spectral Science, Inc. Research by the US Air Force, Navy and Army resulted in the public release of LOWTRAN 2 in the early 1970's. Subsequent releases of LOWTRAN and MODTRAN® have continued until the present. Please verify that (1) all pages are present, (2) all figures are correct, (3) all fonts and special characters are correct, and (4) all text and figures fit within the red margin lines shown on this review document. Complete formatting information is available at http://SPIE.org/manuscripts Return to the Manage Active Submissions page at http://spie.org/submissions/tasks.aspx and approve or disapprove this submission. Your manuscript will not be published without this approval. Please contact author_help@spie.org with any questions or concerns. The paper will demonstrate the importance of using validated models and local measured meteorological, atmospheric and aerosol conditions to accurately simulate the atmospheric transmission and radiance. Frequently default conditions are used which can produce errors of as much as 75% in these values. This can have significant impact on remote sensing applications.
The high cost of accurate knowledge.
Sutcliffe, Kathleen M; Weber, Klaus
2003-05-01
Many business thinkers believe it's the role of senior managers to scan the external environment to monitor contingencies and constraints, and to use that precise knowledge to modify the company's strategy and design. As these thinkers see it, managers need accurate and abundant information to carry out that role. According to that logic, it makes sense to invest heavily in systems for collecting and organizing competitive information. Another school of pundits contends that, since today's complex information often isn't precise anyway, it's not worth going overboard with such investments. In other words, it's not the accuracy and abundance of information that should matter most to top executives--rather, it's how that information is interpreted. After all, the role of senior managers isn't just to make decisions; it's to set direction and motivate others in the face of ambiguities and conflicting demands. Top executives must interpret information and communicate those interpretations--they must manage meaning more than they must manage information. So which of these competing views is the right one? Research conducted by academics Sutcliffe and Weber found that how accurate senior executives are about their competitive environments is indeed less important for strategy and corresponding organizational changes than the way in which they interpret information about their environments. Investments in shaping those interpretations, therefore, may create a more durable competitive advantage than investments in obtaining and organizing more information. And what kinds of interpretations are most closely linked with high performance? Their research suggests that high performers respond positively to opportunities, yet they aren't overconfident in their abilities to take advantage of those opportunities. PMID:12747164
Accurate Weather Forecasting for Radio Astronomy
NASA Astrophysics Data System (ADS)
Maddalena, Ronald J.
2010-01-01
The NRAO Green Bank Telescope routinely observes at wavelengths from 3 mm to 1 m. As with all mm-wave telescopes, observing conditions depend upon the variable atmospheric water content. The site provides over 100 days/yr when opacities are low enough for good observing at 3 mm, but winds on the open-air structure reduce the time suitable for 3-mm observing where pointing is critical. Thus, to maximum productivity the observing wavelength needs to match weather conditions. For 6 years the telescope has used a dynamic scheduling system (recently upgraded; www.gb.nrao.edu/DSS) that requires accurate multi-day forecasts for winds and opacities. Since opacity forecasts are not provided by the National Weather Services (NWS), I have developed an automated system that takes available forecasts, derives forecasted opacities, and deploys the results on the web in user-friendly graphical overviews (www.gb.nrao.edu/ rmaddale/Weather). The system relies on the "North American Mesoscale" models, which are updated by the NWS every 6 hrs, have a 12 km horizontal resolution, 1 hr temporal resolution, run to 84 hrs, and have 60 vertical layers that extend to 20 km. Each forecast consists of a time series of ground conditions, cloud coverage, etc, and, most importantly, temperature, pressure, humidity as a function of height. I use the Liebe's MWP model (Radio Science, 20, 1069, 1985) to determine the absorption in each layer for each hour for 30 observing wavelengths. Radiative transfer provides, for each hour and wavelength, the total opacity and the radio brightness of the atmosphere, which contributes substantially at some wavelengths to Tsys and the observational noise. Comparisons of measured and forecasted Tsys at 22.2 and 44 GHz imply that the forecasted opacities are good to about 0.01 Nepers, which is sufficient for forecasting and accurate calibration. Reliability is high out to 2 days and degrades slowly for longer-range forecasts.
NASA Astrophysics Data System (ADS)
Zhao, Xiao-mei; Xie, Dong-fan; Li, Qi
2015-02-01
With the development of intelligent transport system, advanced information feedback strategies have been developed to reduce traffic congestion and enhance the capacity. However, previous strategies provide accurate information to travelers and our simulation results show that accurate information brings negative effects, especially in delay case. Because travelers prefer to the best condition route with accurate information, and delayed information cannot reflect current traffic condition but past. Then travelers make wrong routing decisions, causing the decrease of the capacity and the increase of oscillations and the system deviating from the equilibrium. To avoid the negative effect, bounded rationality is taken into account by introducing a boundedly rational threshold BR. When difference between two routes is less than the BR, routes have equal probability to be chosen. The bounded rationality is helpful to improve the efficiency in terms of capacity, oscillation and the gap deviating from the system equilibrium.
Anabolic steroid boosts weight.
1996-09-01
A randomized study of nandrolone decanoate (Deca-Durabolin) showed that the anabolic steroid can increase weight in people with HIV infections. The group receiving nandrolone experienced a greater increase both in fat-free mass and body cell mass (although the latter measure did not reach statistical significance) than those on placebo. Deca-Durabolin had little to do with two occurrences of Kaposi's sarcoma (KS) in the study group, but until further studies are completed, caution is advised when using this steroid in patients with KS. A new study comparing nandrolone to growth hormone in patients with wasting is slated to begin in the next 3 or 4 months. PMID:11363845
Tsai, Sandra A; Lv, Nan; Xiao, Lan; Ma, Jun
2016-09-01
Few studies have used nationally representative data to focus specifically on gender differences in weight-related outcomes. This article examines gender differences in weight-related outcomes across the body mass index (BMI) spectrum in overweight and obese adults. Data from the National Health and Nutrition Examination Survey 2009-2010 was analyzed. Weight-related outcomes were accurate weight perception, weight dissatisfaction, attempted weight loss, successful weight loss, and weight loss strategies. Compared with women, overweight and obese men were less likely to have accurate weight perception (odds ratio [OR] = 0.36; 95% confidence interval [CI] = 0.30-0.44), weight dissatisfaction (OR = 0.39; 95% CI = 0.32-0.47), and attempted weight loss (OR = 0.55; 95% CI = 0.48-0.63). The modifying effect of gender on these associations decreased as BMI increased. By BMI 35, the mean probability of women and men to have accurate weight perception and weight dissatisfaction was 90%; attempted weight loss was 60% (women) and 50% (men). At lower BMIs, men had up to 40% less probability than women for these weight loss outcomes. Men who attempted weight loss were more likely than women to lose and maintain ≥10 lb over 1 year (OR = 1.41; 95% CI = 1.20-1.65) and increase exercise and eat less fat as weight loss strategies; women were more likely to join weight loss programs, take prescription diet pills, and follow special diets. A need exists for male-specific interventions to improve overweight and obese men's likelihood for accurate weight perception, attempted weight loss, and ultimately, successful weight loss. PMID:25595019
NASA Technical Reports Server (NTRS)
Graves, R. A., Jr.
1975-01-01
The previously obtained second-order-accurate partial implicitization numerical technique used in the solution of fluid dynamic problems was modified with little complication to achieve fourth-order accuracy. The Von Neumann stability analysis demonstrated the unconditional linear stability of the technique. The order of the truncation error was deduced from the Taylor series expansions of the linearized difference equations and was verified by numerical solutions to Burger's equation. For comparison, results were also obtained for Burger's equation using a second-order-accurate partial-implicitization scheme, as well as the fourth-order scheme of Kreiss.
A Technique of Treating Negative Weights in WENO Schemes
NASA Technical Reports Server (NTRS)
Shi, Jing; Hu, Changqing; Shu, Chi-Wang
2000-01-01
High order accurate weighted essentially non-oscillatory (WENO) schemes have recently been developed for finite difference and finite volume methods both in structural and in unstructured meshes. A key idea in WENO scheme is a linear combination of lower order fluxes or reconstructions to obtain a high order approximation. The combination coefficients, also called linear weights, are determined by local geometry of the mesh and order of accuracy and may become negative. WENO procedures cannot be applied directly to obtain a stable scheme if negative linear weights are present. Previous strategy for handling this difficulty is by either regrouping of stencils or reducing the order of accuracy to get rid of the negative linear weights. In this paper we present a simple and effective technique for handling negative linear weights without a need to get rid of them.
Analytically derived weighting factors for transmission tomography cone beam projections
NASA Astrophysics Data System (ADS)
Yao, Weiguang; Leszczynski, Konrad
2009-02-01
Weighting factors, which define the contributions of individual voxels of a 3D object to individual projection elements (pixels) on the detector, are the basic elements required in iterative tomographic reconstructions from transmission projections. Exact or as accurate as possible values for weighting factors are required in high-resolution reconstructions. Geometric complexity of the problem, however, makes it difficult to obtain exact weighting factor values. In this work, we derive an analytical expression for the weighting factors in cone beam projection geometry. The resulting formula is validated and applied to reconstruction from mega and kilovoltage x-ray cone beam projections. The reconstruction speed and accuracy are significantly improved by using the weighting factor values.
Weighted triangulation adjustment
Anderson, Walter L.
1969-01-01
The variation of coordinates method is employed to perform a weighted least squares adjustment of horizontal survey networks. Geodetic coordinates are required for each fixed and adjustable station. A preliminary inverse geodetic position computation is made for each observed line. Weights associated with each observed equation for direction, azimuth, and distance are applied in the formation of the normal equations in-the least squares adjustment. The number of normal equations that may be solved is twice the number of new stations and less than 150. When the normal equations are solved, shifts are produced at adjustable stations. Previously computed correction factors are applied to the shifts and a most probable geodetic position is found for each adjustable station. Pinal azimuths and distances are computed. These may be written onto magnetic tape for subsequent computation of state plane or grid coordinates. Input consists of punch cards containing project identification, program options, and position and observation information. Results listed include preliminary and final positions, residuals, observation equations, solution of the normal equations showing magnitudes of shifts, and a plot of each adjusted and fixed station. During processing, data sets containing irrecoverable errors are rejected and the type of error is listed. The computer resumes processing of additional data sets.. Other conditions cause warning-errors to be issued, and processing continues with the current data set.
Hwang, Jun Hyun; Ryu, Dong Hee; Park, Soon-Woo
2015-08-01
We investigated the interaction effect between body weight perception and chronic disease comorbidities on body weight control behavior in overweight/obese Korean adults. We analyzed data from 9,138 overweight/obese adults ≥20 yr of age from a nationally representative cross-sectional survey. Multiple logistic regression using an interaction model was performed to estimate the effect of chronic disease comorbidities on weight control behavior regarding weight perception. Adjusted odds ratios for weight control behavior tended to increase significantly with an increasing number of comorbidities in men regardless of weight perception (P<0.05 for trend), suggesting no interaction. Unlike women who perceived their weight accurately, women who under-perceived their weight did not show significant improvements in weight control behavior even with an increasing number of comorbidities. Thus, a significant interaction between weight perception and comorbidities was found only in women (P=0.031 for interaction). The effect of the relationship between accurate weight perception and chronic disease comorbidities on weight control behavior varied by sex. Improving awareness of body image is particularly necessary for overweight and obese women to prevent complications. PMID:26240477
Grappling with Weight Cutting. The Wisconsin Wrestling Minimum Weight Project.
ERIC Educational Resources Information Center
Oppliger, Robert A.; And Others
1995-01-01
In response to a new state rule, the Wisconsin Minimum Weight Project curtails weight cutting among high school wrestlers. The project uses skinfold testing to determine a minimum competitive weight and nutrition education to help the wrestler diet safety. It serves as a model for other states and other sports. (Author/SM)
Modeling operating weight and axle weight distributions for highway vehicles
Greene, D.L.; Liang, J.C.
1988-07-01
The estimation of highway cost responsibility requires detailed information on vehicle operating weights and axle weights by type of vehicle. Typically, 10--20 vehicle types must be cross-classified by 10--20 registered weight classes and again by 20 or more operating weight categories, resulting in 100--400 relative frequencies to be determined for each vehicle type. For each of these, gross operating weight must be distributed to each axle or axle unit. Given the rarity of many of the heaviest vehicle types, direct estimation of these frequencies and axle weights from traffic classification count statistics and truck weight data may exceed the reliability of even the largest (e.g., 250,000 record) data sources. An alternative is to estimate statistical models of operating weight distributions as functions of registered weight, and models of axle weight shares as functions of operating weight. This paper describes the estimation of such functions using the multinomial logit model (a log-linear model) and the implementation of the modeling framework as a PC-based FORTRAN program. Areas for further research include the addition of highway class and region as explanatory variables in operating weight distribution models, and the development of theory for including registration costs and costs of operating overweight in the modeling framework. 14 refs., 45 figs., 5 tabs.
A Simple Model Predicting Individual Weight Change in Humans.
Thomas, Diana M; Martin, Corby K; Heymsfield, Steven; Redman, Leanne M; Schoeller, Dale A; Levine, James A
2011-11-01
Excessive weight in adults is a national concern with over 2/3 of the US population deemed overweight. Because being overweight has been correlated to numerous diseases such as heart disease and type 2 diabetes, there is a need to understand mechanisms and predict outcomes of weight change and weight maintenance. A simple mathematical model that accurately predicts individual weight change offers opportunities to understand how individuals lose and gain weight and can be used to foster patient adherence to diets in clinical settings. For this purpose, we developed a one dimensional differential equation model of weight change based on the energy balance equation is paired to an algebraic relationship between fat free mass and fat mass derived from a large nationally representative sample of recently released data collected by the Centers for Disease Control. We validate the model's ability to predict individual participants' weight change by comparing model estimates of final weight data from two recent underfeeding studies and one overfeeding study. Mean absolute error and standard deviation between model predictions and observed measurements of final weights are less than 1.8 ± 1.3 kg for the underfeeding studies and 2.5 ± 1.6 kg for the overfeeding study. Comparison of the model predictions to other one dimensional models of weight change shows improvement in mean absolute error, standard deviation of mean absolute error, and group mean predictions. The maximum absolute individual error decreased by approximately 60% substantiating reliability in individual weight change predictions. The model provides a viable method for estimating individual weight change as a result of changes in intake and determining individual dietary adherence during weight change studies. PMID:24707319
A Simple Model Predicting Individual Weight Change in Humans
Thomas, Diana M.; Martin, Corby K.; Heymsfield, Steven; Redman, Leanne M.; Schoeller, Dale A.; Levine, James A.
2010-01-01
Excessive weight in adults is a national concern with over 2/3 of the US population deemed overweight. Because being overweight has been correlated to numerous diseases such as heart disease and type 2 diabetes, there is a need to understand mechanisms and predict outcomes of weight change and weight maintenance. A simple mathematical model that accurately predicts individual weight change offers opportunities to understand how individuals lose and gain weight and can be used to foster patient adherence to diets in clinical settings. For this purpose, we developed a one dimensional differential equation model of weight change based on the energy balance equation is paired to an algebraic relationship between fat free mass and fat mass derived from a large nationally representative sample of recently released data collected by the Centers for Disease Control. We validate the model's ability to predict individual participants’ weight change by comparing model estimates of final weight data from two recent underfeeding studies and one overfeeding study. Mean absolute error and standard deviation between model predictions and observed measurements of final weights are less than 1.8 ± 1.3 kg for the underfeeding studies and 2.5 ± 1.6 kg for the overfeeding study. Comparison of the model predictions to other one dimensional models of weight change shows improvement in mean absolute error, standard deviation of mean absolute error, and group mean predictions. The maximum absolute individual error decreased by approximately 60% substantiating reliability in individual weight change predictions. The model provides a viable method for estimating individual weight change as a result of changes in intake and determining individual dietary adherence during weight change studies. PMID:24707319
Accurate Fission Data for Nuclear Safety
NASA Astrophysics Data System (ADS)
Solders, A.; Gorelov, D.; Jokinen, A.; Kolhinen, V. S.; Lantz, M.; Mattera, A.; Penttilä, H.; Pomp, S.; Rakopoulos, V.; Rinta-Antila, S.
2014-05-01
The Accurate fission data for nuclear safety (AlFONS) project aims at high precision measurements of fission yields, using the renewed IGISOL mass separator facility in combination with a new high current light ion cyclotron at the University of Jyväskylä. The 30 MeV proton beam will be used to create fast and thermal neutron spectra for the study of neutron induced fission yields. Thanks to a series of mass separating elements, culminating with the JYFLTRAP Penning trap, it is possible to achieve a mass resolving power in the order of a few hundred thousands. In this paper we present the experimental setup and the design of a neutron converter target for IGISOL. The goal is to have a flexible design. For studies of exotic nuclei far from stability a high neutron flux (1012 neutrons/s) at energies 1 - 30 MeV is desired while for reactor applications neutron spectra that resembles those of thermal and fast nuclear reactors are preferred. It is also desirable to be able to produce (semi-)monoenergetic neutrons for benchmarking and to study the energy dependence of fission yields. The scientific program is extensive and is planed to start in 2013 with a measurement of isomeric yield ratios of proton induced fission in uranium. This will be followed by studies of independent yields of thermal and fast neutron induced fission of various actinides.
Fast and Provably Accurate Bilateral Filtering
NASA Astrophysics Data System (ADS)
Chaudhury, Kunal N.; Dabhade, Swapnil D.
2016-06-01
The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilateral filter requires $O(S)$ operations per pixel, where $S$ is the size of the support of the spatial filter. In this paper, we present a fast and provably accurate algorithm for approximating the bilateral filter when the range kernel is Gaussian. In particular, for box and Gaussian spatial filters, the proposed algorithm can cut down the complexity to $O(1)$ per pixel for any arbitrary $S$. The algorithm has a simple implementation involving $N+1$ spatial filterings, where $N$ is the approximation order. We give a detailed analysis of the filtering accuracy that can be achieved by the proposed approximation in relation to the target bilateral filter. This allows us to to estimate the order $N$ required to obtain a given accuracy. We also present comprehensive numerical results to demonstrate that the proposed algorithm is competitive with state-of-the-art methods in terms of speed and accuracy.
Accurate lineshape spectroscopy and the Boltzmann constant
Truong, G.-W.; Anstie, J. D.; May, E. F.; Stace, T. M.; Luiten, A. N.
2015-01-01
Spectroscopy has an illustrious history delivering serendipitous discoveries and providing a stringent testbed for new physical predictions, including applications from trace materials detection, to understanding the atmospheres of stars and planets, and even constraining cosmological models. Reaching fundamental-noise limits permits optimal extraction of spectroscopic information from an absorption measurement. Here, we demonstrate a quantum-limited spectrometer that delivers high-precision measurements of the absorption lineshape. These measurements yield a very accurate measurement of the excited-state (6P1/2) hyperfine splitting in Cs, and reveals a breakdown in the well-known Voigt spectral profile. We develop a theoretical model that accounts for this breakdown, explaining the observations to within the shot-noise limit. Our model enables us to infer the thermal velocity dispersion of the Cs vapour with an uncertainty of 35 p.p.m. within an hour. This allows us to determine a value for Boltzmann's constant with a precision of 6 p.p.m., and an uncertainty of 71 p.p.m. PMID:26465085
Fast and Provably Accurate Bilateral Filtering.
Chaudhury, Kunal N; Dabhade, Swapnil D
2016-06-01
The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilateral filter requires O(S) operations per pixel, where S is the size of the support of the spatial filter. In this paper, we present a fast and provably accurate algorithm for approximating the bilateral filter when the range kernel is Gaussian. In particular, for box and Gaussian spatial filters, the proposed algorithm can cut down the complexity to O(1) per pixel for any arbitrary S . The algorithm has a simple implementation involving N+1 spatial filterings, where N is the approximation order. We give a detailed analysis of the filtering accuracy that can be achieved by the proposed approximation in relation to the target bilateral filter. This allows us to estimate the order N required to obtain a given accuracy. We also present comprehensive numerical results to demonstrate that the proposed algorithm is competitive with the state-of-the-art methods in terms of speed and accuracy. PMID:27093722
How Accurate are SuperCOSMOS Positions?
NASA Astrophysics Data System (ADS)
Schaefer, Adam; Hunstead, Richard; Johnston, Helen
2014-02-01
Optical positions from the SuperCOSMOS Sky Survey have been compared in detail with accurate radio positions that define the second realisation of the International Celestial Reference Frame (ICRF2). The comparison was limited to the IIIaJ plates from the UK/AAO and Oschin (Palomar) Schmidt telescopes. A total of 1 373 ICRF2 sources was used, with the sample restricted to stellar objects brighter than BJ = 20 and Galactic latitudes |b| > 10°. Position differences showed an rms scatter of
Accurate adiabatic correction in the hydrogen molecule
Pachucki, Krzysztof; Komasa, Jacek
2014-12-14
A new formalism for the accurate treatment of adiabatic effects in the hydrogen molecule is presented, in which the electronic wave function is expanded in the James-Coolidge basis functions. Systematic increase in the size of the basis set permits estimation of the accuracy. Numerical results for the adiabatic correction to the Born-Oppenheimer interaction energy reveal a relative precision of 10{sup −12} at an arbitrary internuclear distance. Such calculations have been performed for 88 internuclear distances in the range of 0 < R ⩽ 12 bohrs to construct the adiabatic correction potential and to solve the nuclear Schrödinger equation. Finally, the adiabatic correction to the dissociation energies of all rovibrational levels in H{sub 2}, HD, HT, D{sub 2}, DT, and T{sub 2} has been determined. For the ground state of H{sub 2} the estimated precision is 3 × 10{sup −7} cm{sup −1}, which is almost three orders of magnitude higher than that of the best previous result. The achieved accuracy removes the adiabatic contribution from the overall error budget of the present day theoretical predictions for the rovibrational levels.
Accurate adiabatic correction in the hydrogen molecule
NASA Astrophysics Data System (ADS)
Pachucki, Krzysztof; Komasa, Jacek
2014-12-01
A new formalism for the accurate treatment of adiabatic effects in the hydrogen molecule is presented, in which the electronic wave function is expanded in the James-Coolidge basis functions. Systematic increase in the size of the basis set permits estimation of the accuracy. Numerical results for the adiabatic correction to the Born-Oppenheimer interaction energy reveal a relative precision of 10-12 at an arbitrary internuclear distance. Such calculations have been performed for 88 internuclear distances in the range of 0 < R ⩽ 12 bohrs to construct the adiabatic correction potential and to solve the nuclear Schrödinger equation. Finally, the adiabatic correction to the dissociation energies of all rovibrational levels in H2, HD, HT, D2, DT, and T2 has been determined. For the ground state of H2 the estimated precision is 3 × 10-7 cm-1, which is almost three orders of magnitude higher than that of the best previous result. The achieved accuracy removes the adiabatic contribution from the overall error budget of the present day theoretical predictions for the rovibrational levels.
MEMS accelerometers in accurate mount positioning systems
NASA Astrophysics Data System (ADS)
Mészáros, László; Pál, András.; Jaskó, Attila
2014-07-01
In order to attain precise, accurate and stateless positioning of telescope mounts we apply microelectromechanical accelerometer systems (also known as MEMS accelerometers). In common practice, feedback from the mount position is provided by electronic, optical or magneto-mechanical systems or via real-time astrometric solution based on the acquired images. Hence, MEMS-based systems are completely independent from these mechanisms. Our goal is to investigate the advantages and challenges of applying such devices and to reach the sub-arcminute range { that is well smaller than the field-of-view of conventional imaging telescope systems. We present how this sub-arcminute accuracy can be achieved with very cheap MEMS sensors. Basically, these sensors yield raw output within an accuracy of a few degrees. We show what kind of calibration procedures could exploit spherical and cylindrical constraints between accelerometer output channels in order to achieve the previously mentioned accuracy level. We also demonstrate how can our implementation be inserted in a telescope control system. Although this attainable precision is less than both the resolution of telescope mount drive mechanics and the accuracy of astrometric solutions, the independent nature of attitude determination could significantly increase the reliability of autonomous or remotely operated astronomical observations.
Accurate, reliable prototype earth horizon sensor head
NASA Technical Reports Server (NTRS)
Schwarz, F.; Cohen, H.
1973-01-01
The design and performance is described of an accurate and reliable prototype earth sensor head (ARPESH). The ARPESH employs a detection logic 'locator' concept and horizon sensor mechanization which should lead to high accuracy horizon sensing that is minimally degraded by spatial or temporal variations in sensing attitude from a satellite in orbit around the earth at altitudes in the 500 km environ 1,2. An accuracy of horizon location to within 0.7 km has been predicted, independent of meteorological conditions. This corresponds to an error of 0.015 deg-at 500 km altitude. Laboratory evaluation of the sensor indicates that this accuracy is achieved. First, the basic operating principles of ARPESH are described; next, detailed design and construction data is presented and then performance of the sensor under laboratory conditions in which the sensor is installed in a simulator that permits it to scan over a blackbody source against background representing the earth space interface for various equivalent plant temperatures.
Accurate lineshape spectroscopy and the Boltzmann constant.
Truong, G-W; Anstie, J D; May, E F; Stace, T M; Luiten, A N
2015-01-01
Spectroscopy has an illustrious history delivering serendipitous discoveries and providing a stringent testbed for new physical predictions, including applications from trace materials detection, to understanding the atmospheres of stars and planets, and even constraining cosmological models. Reaching fundamental-noise limits permits optimal extraction of spectroscopic information from an absorption measurement. Here, we demonstrate a quantum-limited spectrometer that delivers high-precision measurements of the absorption lineshape. These measurements yield a very accurate measurement of the excited-state (6P1/2) hyperfine splitting in Cs, and reveals a breakdown in the well-known Voigt spectral profile. We develop a theoretical model that accounts for this breakdown, explaining the observations to within the shot-noise limit. Our model enables us to infer the thermal velocity dispersion of the Cs vapour with an uncertainty of 35 p.p.m. within an hour. This allows us to determine a value for Boltzmann's constant with a precision of 6 p.p.m., and an uncertainty of 71 p.p.m. PMID:26465085
Fast and Accurate Exhaled Breath Ammonia Measurement
Solga, Steven F.; Mudalel, Matthew L.; Spacek, Lisa A.; Risby, Terence H.
2014-01-01
This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations. PMID:24962141
Fast, accurate, robust and Open Source Brain Extraction Tool (OSBET)
NASA Astrophysics Data System (ADS)
Namias, R.; Donnelly Kehoe, P.; D'Amato, J. P.; Nagel, J.
2015-12-01
The removal of non-brain regions in neuroimaging is a critical task to perform a favorable preprocessing. The skull-stripping depends on different factors including the noise level in the image, the anatomy of the subject being scanned and the acquisition sequence. For these and other reasons, an ideal brain extraction method should be fast, accurate, user friendly, open-source and knowledge based (to allow for the interaction with the algorithm in case the expected outcome is not being obtained), producing stable results and making it possible to automate the process for large datasets. There are already a large number of validated tools to perform this task but none of them meets the desired characteristics. In this paper we introduced an open source brain extraction tool (OSBET), composed of four steps using simple well-known operations such as: optimal thresholding, binary morphology, labeling and geometrical analysis that aims to assemble all the desired features. We present an experiment comparing OSBET with other six state-of-the-art techniques against a publicly available dataset consisting of 40 T1-weighted 3D scans and their corresponding manually segmented images. OSBET gave both: a short duration with an excellent accuracy, getting the best Dice Coefficient metric. Further validation should be performed, for instance, in unhealthy population, to generalize its usage for clinical purposes.
Extensive and Highly Accurate Line Lists for Hydrogen Halides
NASA Astrophysics Data System (ADS)
Li, G.; Bernath, P. F.; Gordon, I. E.; Rothman, L. S.; Richard, C.; Le Roy, R. J.; Coxon, J. A.; Hajigeorgiou, P.
2011-06-01
New dipole moment functions (DMF) for the ground X 1Σ+ electronic states of the hydrogen halides (HF, HCl, HBr, HI) have been obtained using a direct fit approach that fits the best available and appropriately weighted experimental line intensity data for individual ro-vibrational transitions. Combining the newly developed (taking into account the most recent experiments) empirical potential energy functions and the DMFs, line positions and line intensities of the hydrogen halides and their isotopologues have been calculated numerically using program LEVEL. In addition, new semi-empirical algorithms for assigning line-shape parameters for these species have been developed. Using these improvements, new line lists for hydrogen halides were created to update the HITRAN spectroscopic database. These new lists are more accurate and significantly more extensive than those included in the current version of the database (HITRAN2008). R.J. Le Roy, ``LEVEL 8.0, 2007'', University of Waterloo Chemical Physics Research Report CP-663 (2007); see http://leroy.uwaterloo.ca/programs/. L.S. Rothman, I.E. Gordon, A. Barbe, D.C. Benner, P.F. Bernath, et al., ``The HITRAN 2008 Molecular Spectroscopic Database,'' JQSRT 110, 532-572 (2009).
Atomic Weights and Isotopic Compositions
National Institute of Standards and Technology Data Gateway
SRD 144 Atomic Weights and Isotopic Compositions (Web, free access) The atomic weights are available for elements 1 through 111, and isotopic compositions or abundances are given when appropriate.
Weight-Control Information Network
... Research Training & Career Development Grant programs for students, postdocs, and faculty Research at NIDDK Labs, faculty, and ... full list of resources . Alternate Language URL Weight-control Information Network (WIN) Page Content The Weight-control ...
NASA Astrophysics Data System (ADS)
Schatten, Kenneth
1984-04-01
Having for numerous reasons acquired a three digit kilogram mass, the author is experienced at the painful struggles that the gourmand must suffer to reduce weight, particularly if he/she enjoys reasonably large amounts of good food. To the avant-garde geophysicist, utilizing the following approach could be pleasurable, rewarding, and may even enable the accomplishment of what Ghengis Khan, Alexander the Great, Napolean, and Hitler could not!The basic approach is the full utilization of Newton's formula for the attraction of two massive bodies: F=GM1M2/r2, where G, is the gravitational constant; r, the distance between the two bodies; and M1 and M2, the masses of the two bodies. Although one usually chooses M1 to be the earth's mass ME and M2 to be the mass of a small object, this unnecessarily restricts the realm of phenomena. The less restrictive assumption is M1 + M2 = ME.
Gohlke, H
2002-01-01
Certain dietary components play a key role for the development of coronary artery disease (CAD). Complex carbohydrates lower the prevalence of CAD. Protein should provide 15% of daily calories. Populations with a high consumption of soy protein have a low coronary event rate and a high life expectancy. Soy protein has a favorable effect on LDL cholesterol, triglycerides and HDL cholesterol. Dietary cholesterol correlates with an increased incidence of CAD. Saturated fats increase cholesterol levels as well as the activity of clotting factor VII and promote progression of CAD. Mono-(MUFA) and poly-unsaturated fatty acids lower LDL-cholesterol to a similar extent. MUFA are contained in rape seed oil, olive oil and pea nut oil, but also in avocados and almonds. Omega-3-fatty acids are in fatty fish like salmon, tuna and herring and improve survival after myocardial infarction. They improve among others endothelial function (adhesion molecules). Eating 1-2 fish meals per week has a preventive effect on CAD and stroke. Dietary fiber decreases the risk for CAD up to 30% and favorably influences carbohydrate metabolism. Antioxidants have a favorable effect in their natural form (fruits and fresh vegetables). The secondary preventive effect of a mediterranean diet after myocardial infarction (probably by a combination of the above effects) has been validated. Body weight correlates with coronary risk, diabetes and use of health care resources. A reduction of body weight is best achieved by calory reduction plus an increase of physical activity. A calory-adjusted diet, low in total fat with a significant proportion of unsaturated fats and omega-3-fatty acids and rich in fiber is of great importance for primary and secondary prevention of cardiovascular diseases. Fruits, vegetables and whole grain products are important components of this diet, which lowers the coronary event rate, increases longevity and is associated with a low rate of malignancies and osteoporosis. PMID
Accurate orbit propagation with planetary close encounters
NASA Astrophysics Data System (ADS)
Baù, Giulio; Milani Comparetti, Andrea; Guerra, Francesca
2015-08-01
We tackle the problem of accurately propagating the motion of those small bodies that undergo close approaches with a planet. The literature is lacking on this topic and the reliability of the numerical results is not sufficiently discussed. The high-frequency components of the perturbation generated by a close encounter makes the propagation particularly challenging both from the point of view of the dynamical stability of the formulation and the numerical stability of the integrator. In our approach a fixed step-size and order multistep integrator is combined with a regularized formulation of the perturbed two-body problem. When the propagated object enters the region of influence of a celestial body, the latter becomes the new primary body of attraction. Moreover, the formulation and the step-size will also be changed if necessary. We present: 1) the restarter procedure applied to the multistep integrator whenever the primary body is changed; 2) new analytical formulae for setting the step-size (given the order of the multistep, formulation and initial osculating orbit) in order to control the accumulation of the local truncation error and guarantee the numerical stability during the propagation; 3) a new definition of the region of influence in the phase space. We test the propagator with some real asteroids subject to the gravitational attraction of the planets, the Yarkovsky and relativistic perturbations. Our goal is to show that the proposed approach improves the performance of both the propagator implemented in the OrbFit software package (which is currently used by the NEODyS service) and of the propagator represented by a variable step-size and order multistep method combined with Cowell's formulation (i.e. direct integration of position and velocity in either the physical or a fictitious time).
How flatbed scanners upset accurate film dosimetry.
van Battum, L J; Huizenga, H; Verdaasdonk, R M; Heukelom, S
2016-01-21
Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner's transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner's optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film. PMID:26689962
Accurate paleointensities - the multi-method approach
NASA Astrophysics Data System (ADS)
de Groot, Lennart
2016-04-01
The accuracy of models describing rapid changes in the geomagnetic field over the past millennia critically depends on the availability of reliable paleointensity estimates. Over the past decade methods to derive paleointensities from lavas (the only recorder of the geomagnetic field that is available all over the globe and through geologic times) have seen significant improvements and various alternative techniques were proposed. The 'classical' Thellier-style approach was optimized and selection criteria were defined in the 'Standard Paleointensity Definitions' (Paterson et al, 2014). The Multispecimen approach was validated and the importance of additional tests and criteria to assess Multispecimen results must be emphasized. Recently, a non-heating, relative paleointensity technique was proposed -the pseudo-Thellier protocol- which shows great potential in both accuracy and efficiency, but currently lacks a solid theoretical underpinning. Here I present work using all three of the aforementioned paleointensity methods on suites of young lavas taken from the volcanic islands of Hawaii, La Palma, Gran Canaria, Tenerife, and Terceira. Many of the sampled cooling units are <100 years old, the actual field strength at the time of cooling is therefore reasonably well known. Rather intuitively, flows that produce coherent results from two or more different paleointensity methods yield the most accurate estimates of the paleofield. Furthermore, the results for some flows pass the selection criteria for one method, but fail in other techniques. Scrutinizing and combing all acceptable results yielded reliable paleointensity estimates for 60-70% of all sampled cooling units - an exceptionally high success rate. This 'multi-method paleointensity approach' therefore has high potential to provide the much-needed paleointensities to improve geomagnetic field models for the Holocene.
Important Nearby Galaxies without Accurate Distances
NASA Astrophysics Data System (ADS)
McQuinn, Kristen
2014-10-01
The Spitzer Infrared Nearby Galaxies Survey (SINGS) and its offspring programs (e.g., THINGS, HERACLES, KINGFISH) have resulted in a fundamental change in our view of star formation and the ISM in galaxies, and together they represent the most complete multi-wavelength data set yet assembled for a large sample of nearby galaxies. These great investments of observing time have been dedicated to the goal of understanding the interstellar medium, the star formation process, and, more generally, galactic evolution at the present epoch. Nearby galaxies provide the basis for which we interpret the distant universe, and the SINGS sample represents the best studied nearby galaxies.Accurate distances are fundamental to interpreting observations of galaxies. Surprisingly, many of the SINGS spiral galaxies have numerous distance estimates resulting in confusion. We can rectify this situation for 8 of the SINGS spiral galaxies within 10 Mpc at a very low cost through measurements of the tip of the red giant branch. The proposed observations will provide an accuracy of better than 0.1 in distance modulus. Our sample includes such well known galaxies as M51 (the Whirlpool), M63 (the Sunflower), M104 (the Sombrero), and M74 (the archetypal grand design spiral).We are also proposing coordinated parallel WFC3 UV observations of the central regions of the galaxies, rich with high-mass UV-bright stars. As a secondary science goal we will compare the resolved UV stellar populations with integrated UV emission measurements used in calibrating star formation rates. Our observations will complement the growing HST UV atlas of high resolution images of nearby galaxies.
Towards Accurate Application Characterization for Exascale (APEX)
Hammond, Simon David
2015-09-01
Sandia National Laboratories has been engaged in hardware and software codesign activities for a number of years, indeed, it might be argued that prototyping of clusters as far back as the CPLANT machines and many large capability resources including ASCI Red and RedStorm were examples of codesigned solutions. As the research supporting our codesign activities has moved closer to investigating on-node runtime behavior a nature hunger has grown for detailed analysis of both hardware and algorithm performance from the perspective of low-level operations. The Application Characterization for Exascale (APEX) LDRD was a project concieved of addressing some of these concerns. Primarily the research was to intended to focus on generating accurate and reproducible low-level performance metrics using tools that could scale to production-class code bases. Along side this research was an advocacy and analysis role associated with evaluating tools for production use, working with leading industry vendors to develop and refine solutions required by our code teams and to directly engage with production code developers to form a context for the application analysis and a bridge to the research community within Sandia. On each of these accounts significant progress has been made, particularly, as this report will cover, in the low-level analysis of operations for important classes of algorithms. This report summarizes the development of a collection of tools under the APEX research program and leaves to other SAND and L2 milestone reports the description of codesign progress with Sandia’s production users/developers.
How flatbed scanners upset accurate film dosimetry
NASA Astrophysics Data System (ADS)
van Battum, L. J.; Huizenga, H.; Verdaasdonk, R. M.; Heukelom, S.
2016-01-01
Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner’s transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner’s optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film.
Human biology of weight maintenance after weight loss.
Mariman, Edwin C M
2012-01-01
One year after losing weight, most people have regained a significant part of the lost weight. As such, weight regain after weight loss has a negative impact on human health. The risk for weight regain is determined by psychosocial and behavioral factors as well as by various physiological and molecular parameters. Here, the latter intrinsic factors are reviewed and assembled into four functional modules, two related to the energy balance and two related to resistance against weight loss. Reported genetic factors do not reveal additional functional processes. The modules form nodes in a network describing the complex interactions of intrinsically determined weight maintenance. This network indicates that after an initial weight loss persons with a high baseline fat mass will most easily succeed in maintaining weight, because they can lose fat without raising stress in adipocytes and at the same time spare fat-free mass. However, continued weight loss and weight maintenance requires extra measures like increased physical activity, limited energy intake and a fat-free sparing composition of the diet. Eventually, this network may help to design novel therapeutic measures based on preventing the return effect of specific plasma factors or by preventing the accumulation of adipocyte cellular stress. PMID:22472972
The weight of mass or the mass of weight
NASA Astrophysics Data System (ADS)
Gat, U.
1987-06-01
This paper explores the cause of confusion associated with the words mass and weight, and offers suggestions to correct the problem. It is recommended that in technical and scientific use, weight shall be restricted to mean force of gravity. Technical standards, ASTM and others, and terminology shall clearly reflect and define weight to be force of gravity. Weight should be avoided in technical context because of its imprecision. Legal, formal, and official language shall use weight to mean force only. Under no circumstances should the SI units of mass, the kilogram, or its derivatives, be associated with weight. The term weight should be avoided in any language and wording that intends to convey a precise or important meaning. ASTM should revise all standards and terminology accordingly.
Successful habits of weight losers
Technology Transfer Automated Retrieval System (TEKTRAN)
Despite the availability of the US Dietary Guidelines for Americans, the prevalence of obesity in adults has increased by 200% since 1980. Although few people have lost weight and maintained weight loss long term, some have and are tracked by the National Weight Control Registry. Results from these ...
Fungible Weights in Multiple Regression
ERIC Educational Resources Information Center
Waller, Niels G.
2008-01-01
Every set of alternate weights (i.e., nonleast squares weights) in a multiple regression analysis with three or more predictors is associated with an infinite class of weights. All members of a given class can be deemed "fungible" because they yield identical "SSE" (sum of squared errors) and R[superscript 2] values. Equations for generating…
Correlation Weights in Multiple Regression
ERIC Educational Resources Information Center
Waller, Niels G.; Jones, Jeff A.
2010-01-01
A general theory on the use of correlation weights in linear prediction has yet to be proposed. In this paper we take initial steps in developing such a theory by describing the conditions under which correlation weights perform well in population regression models. Using OLS weights as a comparison, we define cases in which the two weighting…
Hypnotherapy in Weight Loss Treatment.
ERIC Educational Resources Information Center
Cochrane, Gordon; Friesen, John
1986-01-01
Investigated effects of hypnosis as a treatment for weight loss among women. The primary hypothesis that hypnosis is an effective treatment for weight loss was confirmed, but seven concomitant variables and the use of audiotapes were not significant contributors to weight loss. (Author/ABB)
Weight Training for Wheelchair Sports.
ERIC Educational Resources Information Center
Practical Pointers, 1978
1978-01-01
The article examines weight lifting training procedures for persons involved in wheelchair sports. Popular myths about weight training are countered, and guidelines for a safe and sound weight or resistance training program are given. Diagrams and descriptions follow for specific weightlifting activities: regular or standing press, military press,…
Physiological adaptations to weight loss and factors favouring weight regain
Greenway, F L
2015-01-01
Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an ‘obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their
Physiological adaptations to weight loss and factors favouring weight regain.
Greenway, F L
2015-08-01
Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an 'obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their efforts
Accurate theoretical chemistry with coupled pair models.
Neese, Frank; Hansen, Andreas; Wennmohs, Frank; Grimme, Stefan
2009-05-19
Quantum chemistry has found its way into the everyday work of many experimental chemists. Calculations can predict the outcome of chemical reactions, afford insight into reaction mechanisms, and be used to interpret structure and bonding in molecules. Thus, contemporary theory offers tremendous opportunities in experimental chemical research. However, even with present-day computers and algorithms, we cannot solve the many particle Schrodinger equation exactly; inevitably some error is introduced in approximating the solutions of this equation. Thus, the accuracy of quantum chemical calculations is of critical importance. The affordable accuracy depends on molecular size and particularly on the total number of atoms: for orientation, ethanol has 9 atoms, aspirin 21 atoms, morphine 40 atoms, sildenafil 63 atoms, paclitaxel 113 atoms, insulin nearly 800 atoms, and quaternary hemoglobin almost 12,000 atoms. Currently, molecules with up to approximately 10 atoms can be very accurately studied by coupled cluster (CC) theory, approximately 100 atoms with second-order Møller-Plesset perturbation theory (MP2), approximately 1000 atoms with density functional theory (DFT), and beyond that number with semiempirical quantum chemistry and force-field methods. The overwhelming majority of present-day calculations in the 100-atom range use DFT. Although these methods have been very successful in quantum chemistry, they do not offer a well-defined hierarchy of calculations that allows one to systematically converge to the correct answer. Recently a number of rather spectacular failures of DFT methods have been found-even for seemingly simple systems such as hydrocarbons, fueling renewed interest in wave function-based methods that incorporate the relevant physics of electron correlation in a more systematic way. Thus, it would be highly desirable to fill the gap between 10 and 100 atoms with highly correlated ab initio methods. We have found that one of the earliest (and now
Holiday Weight Management by Successful Weight Losers and Normal Weight Individuals
ERIC Educational Resources Information Center
Phelan, Suzanne; Wing, Rena R.; Raynor, Hollie A.; Dibello, Julia; Nedeau, Kim; Peng, Wanfeng
2008-01-01
This study compared weight control strategies during the winter holidays among successful weight losers (SWL) in the National Weight Control Registry and normal weight individuals (NW) with no history of obesity. SWL (n = 178) had lost a mean of 34.9 kg and had kept greater than or equal to 13.6 kg off for a mean of 5.9 years. NW (n = 101) had a…
Accuracy and consistency of weights provided by home bathroom scales
2013-01-01
Background Self-reported body weight is often used for calculation of Body Mass Index because it is easy to collect. Little is known about sources of error introduced by using bathroom scales to measure weight at home. The objective of this study was to evaluate the accuracy and consistency of digital versus dial-type bathroom scales commonly used for self-reported weight. Methods Participants brought functioning bathroom scales (n = 18 dial-type, n = 43 digital-type) to a central location. Trained researchers assessed accuracy and consistency using certified calibration weights at 10 kg, 25 kg, 50 kg, 75 kg, 100 kg, and 110 kg. Data also were collected on frequency of calibration, age and floor surface beneath the scale. Results All participants reported using their scale on hard surface flooring. Before calibration, all digital scales displayed 0, but dial scales displayed a mean absolute initial weight of 0.95 (1.9 SD) kg. Digital scales accurately weighed test loads whereas dial-type scale weights differed significantly (p < 0.05). Imprecision of dial scales was significantly greater than that of digital scales at all weights (p < 0.05). Accuracy and precision did not vary by scale age. Conclusions Digital home bathroom scales provide sufficiently accurate and consistent weights for public health research. Reminders to zero scales before each use may further improve accuracy of self-reported weight. PMID:24341761
Infrared target tracking via weighted correlation filter
NASA Astrophysics Data System (ADS)
He, Yu-Jie; Li, Min; Zhang, JinLi; Yao, Jun-Ping
2015-11-01
Design of an effective target tracker is an important and challenging task for many applications due to multiple factors which can cause disturbance in infrared video sequences. In this paper, an infrared target tracking method under tracking by detection framework based on a weighted correlation filter is presented. This method consists of two parts: detection and filtering. For the detection stage, we propose a sequential detection method for the infrared target based on low-rank representation. For the filtering stage, a new multi-feature weighted function which fuses different target features is proposed, which takes the importance of the different regions into consideration. The weighted function is then incorporated into a correlation filter to compute a confidence map more accurately, in order to indicate the best target location based on the detection results obtained from the first stage. Extensive experimental results on different video sequences demonstrate that the proposed method performs favorably for detection and tracking compared with baseline methods in terms of efficiency and accuracy.
Anthropometric approximation of body weight in unresponsive stroke patients
Lorenz, M W; Graf, M; Henke, C; Hermans, M; Ziemann, U; Sitzer, M; Foerch, C
2007-01-01
Background and purpose Thrombolysis of acute ischaemic stroke is based strictly on body weight to ensure efficacy and to prevent bleeding complications. Many candidate stroke patients are unable to communicate their body weight, and there is often neither the means nor the time to weigh the patient. Instead, weight is estimated visually by the attending physician, but this is known to be inaccurate. Methods Based on a large general population sample of nearly 7000 subjects, we constructed approximation formulae for estimating body weight from simple anthropometric measurements (body height, and waist and hip circumference). These formulae were validated in a sample of 178 consecutive inpatients admitted to our stroke unit, and their accuracy was compared with the best visual estimation of two experienced physicians. Results The simplest formula gave the most accurate approximation (mean absolute difference 3.1 (2.6) kg), which was considerably better than the best visual estimation (physician 1: 6.5 (5.2) kg; physician 2: 7.4 (5.7) kg). It reduced the proportion of weight approximations mismatched by >10% from 31.5% and 40.4% (physicians 1 and 2, respectively) to 6.2% (anthropometric approximation). Only the patient's own estimation was more accurate (mean absolute difference 2.7 (2.4) kg). Conclusions By using an approximation formula based on simple anthropometric measurements (body height, and waist and hip circumference), it is possible to obtain a quick and accurate approximation of body weight. In situations where the exact weight of unresponsive patients cannot be ascertained quickly, we recommend using this approximation method rather than visual estimation. PMID:17494978
NASA Technical Reports Server (NTRS)
Grissom, D. S.; Schneider, W. C.
1971-01-01
The determination of a base line (minimum weight) design for the primary structure of the living quarters modules in an earth-orbiting space base was investigated. Although the design is preliminary in nature, the supporting analysis is sufficiently thorough to provide a reasonably accurate weight estimate of the major components that are considered to comprise the structural weight of the space base.
Ness-Abramof, Rosane; Apovian, Caroline M
2005-01-01
Drug-induced weight gain is a serious side effect of many commonly used drugs leading to noncompliance with therapy and to exacerbation of comorbid conditions related to obesity. Improved glycemic control achieved by insulin, insulin secretagogues or thiazolidinedione therapy is generally accompanied by weight gain. It is a problematic side effect of therapy due to the known deleterious effect of weight gain on glucose control, increased blood pressure and worsening lipid profile. Weight gain may be lessened or prevented by adherence to diet and exercise or combination therapy with metformin. Weight gain is also common in psychotropic therapy. The atypical antipsychotic drugs (clozapine, olanzepine, risperidone and quetiapine) are known to cause marked weight gain. Antidepressants such as amitriptyline, mirtazapine and some serotonin reuptake inhibitors (SSRIs) also may promote appreciable weight gain that cannot be explained solely by improvement in depressive symptoms. The same phenomenon is observed with mood stabilizers such as lithium, valproic acid and carbamazepine. Antiepileptic drugs (AEDs) that promote weight gain include valproate, carbamazepine and gabapentin. Lamotrigine is an AED that is weight-neutral, while topiramate and zonisamide may induce weight loss. PMID:16341287
Ness-Abramof, Rosane; Apovian, Caroline M
2005-08-01
Drug-induced weight gain is a serious side effect of many commonly used drugs leading to noncompliance with therapy and to exacerbation of comorbid conditions related to obesity. Improved glycemic control achieved by insulin, insulin secretagogues or thiazolidinedione therapy is generally accompanied by weight gain. It is a problematic side effect of therapy due to the known deleterious effect of weight gain on glucose control, increased blood pressure and worsening lipid profile. Weight gain may be lessened or prevented by adherence to diet and exercise or combination therapy with metformin. Weight gain is also common in psychotropic therapy. The atypical antipsychotic drugs (clozapine, olanzepine, risperidone and quetiapine) are known to cause marked weight gain. Antidepressants such as amitriptyline, mirtazapine and some serotonin reuptake inhibitors (SSRIs) also may promote appreciable weight gain that cannot be explained solely by improvement in depressive symptoms. The same phenomenon is observed with mood stabilizers such as lithium, valproic acid and carbamazepine. Antiepileptic drugs (AEDs) that promote weight gain include valproate, carbamazepine and gabapentin. Lamotrigine is an AED that is weight-neutral, while topiramate and zonisamide may induce weight loss. PMID:16234878
Handling Dynamic Weights in Weighted Frequent Pattern Mining
NASA Astrophysics Data System (ADS)
Ahmed, Chowdhury Farhan; Tanbeer, Syed Khairuzzaman; Jeong, Byeong-Soo; Lee, Young-Koo
Even though weighted frequent pattern (WFP) mining is more effective than traditional frequent pattern mining because it can consider different semantic significances (weights) of items, existing WFP algorithms assume that each item has a fixed weight. But in real world scenarios, the weight (price or significance) of an item can vary with time. Reflecting these changes in item weight is necessary in several mining applications, such as retail market data analysis and web click stream analysis. In this paper, we introduce the concept of a dynamic weight for each item, and propose an algorithm, DWFPM (dynamic weighted frequent pattern mining), that makes use of this concept. Our algorithm can address situations where the weight (price or significance) of an item varies dynamically. It exploits a pattern growth mining technique to avoid the level-wise candidate set generation-and-test methodology. Furthermore, it requires only one database scan, so it is eligible for use in stream data mining. An extensive performance analysis shows that our algorithm is efficient and scalable for WFP mining using dynamic weights.
Mass spectrometry-based protein identification with accurate statistical significance assignment
Alves, Gelio; Yu, Yi-Kuo
2015-01-01
Motivation: Assigning statistical significance accurately has become increasingly important as metadata of many types, often assembled in hierarchies, are constructed and combined for further biological analyses. Statistical inaccuracy of metadata at any level may propagate to downstream analyses, undermining the validity of scientific conclusions thus drawn. From the perspective of mass spectrometry-based proteomics, even though accurate statistics for peptide identification can now be achieved, accurate protein level statistics remain challenging. Results: We have constructed a protein ID method that combines peptide evidences of a candidate protein based on a rigorous formula derived earlier; in this formula the database P-value of every peptide is weighted, prior to the final combination, according to the number of proteins it maps to. We have also shown that this protein ID method provides accurate protein level E-value, eliminating the need of using empirical post-processing methods for type-I error control. Using a known protein mixture, we find that this protein ID method, when combined with the Sorić formula, yields accurate values for the proportion of false discoveries. In terms of retrieval efficacy, the results from our method are comparable with other methods tested. Availability and implementation: The source code, implemented in C++ on a linux system, is available for download at ftp://ftp.ncbi.nlm.nih.gov/pub/qmbp/qmbp_ms/RAId/RAId_Linux_64Bit. Contact: yyu@ncbi.nlm.nih.gov Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25362092
Global cost and weight evaluation of fuselage keel design concepts
NASA Technical Reports Server (NTRS)
Flynn, B. W.; Morris, M. R.; Metschan, S. L.; Swanson, G. D.; Smith, P. J.; Griess, K. H.; Schramm, M. R.; Humphrey, R. J.
1993-01-01
The Boeing program entitled Advanced Technology Composite Aircraft Structure (ATCAS) is focused on the application of affordable composite technology to pressurized fuselage structure of future aircraft. As part of this effort, a design study was conducted on the keel section of the aft fuselage. A design build team (DBT) approach was used to identify and evaluate several design concepts which incorporated different material systems, fabrication processes, structural configurations, and subassembly details. The design concepts were developed in sufficient detail to accurately assess their potential for cost and weight savings as compared with a metal baseline representing current wide body technology. The cost and weight results, along with an appraisal of performance and producibility risks, are used to identify a globally optimized keel design; one which offers the most promising cost and weight advantages over metal construction. Lastly, an assessment is given of the potential for further cost and weight reductions of the selected keel design during local optimization.
Chen, Qiang; Yang, Bicheng
2016-01-01
By means of weight functions and Hermite-Hadamard's inequality, and introducing a discrete interval variable, a more accurate half-discrete Hardy-Hilbert-type inequality related to the kernel of arc tangent function and a best possible constant factor is given, which is an extension of a published result. The equivalent forms and the operator expressions are also considered. PMID:27563512
Weight reduction, fertility and contraception.
Van Der Spuy, Z M; Jacobs, H S
1983-10-01
The significance of weight and body composition with regard to the fertile menstrual cycle has excited much interest. There is global imbalance of resources and problems of widespread chronic malnutrition in many 3rd world countries. This emphasizes the great importance of the possible effects of diet, body weight, and body composition on fecundity (ability to reproduce), fertility (reproductive performance), and pregnancy outcome. Frisch and Revelle suggested that a critical body weight is required for a girl to progress through puberty, menstruate, and finally develop ovulatory cycles. They postulated a direct relationship between weight and menarche and suggested that before menarche will occur at least 17% of the body weight needs to be made up of fat. The Frisch hypothesis is not universally accepted, and it seems highly unlikely that a single age unrelated body weight is always the trigger for menarche. Many of the data used in Frische's original studies were derived rather than directly observed. It seems likely that both body weight and composition are important and that the peripheral conversion of androgens to estrogens in fat plays a role in pubertal development, but the actual signal whcih triggers the hypothalamic events leading eventually through puberty to menstruation and ovulation remains unkown. Acute malnutrition, as seen during famine, is assoicated with a dramatic decrease in fertility. It is usually secondary to amenorrhea and annovulation. In developing countries weight related amenorrhea and delayed menarche are largely the result of nutritonal deprivation and the demands of lactation on women of boderline body weight, but a different pattern is seen in Western countries. The outstanding example of weight reduction resulting in infertility is seen in patients with anorexia nervosa. These women have extreme self imposed weight loss, a distorted perception of their body image, and disturbance in their attitude towards their feelings of hunger
Accurate deterministic solutions for the classic Boltzmann shock profile
NASA Astrophysics Data System (ADS)
Yue, Yubei
The Boltzmann equation or Boltzmann transport equation is a classical kinetic equation devised by Ludwig Boltzmann in 1872. It is regarded as a fundamental law in rarefied gas dynamics. Rather than using macroscopic quantities such as density, temperature, and pressure to describe the underlying physics, the Boltzmann equation uses a distribution function in phase space to describe the physical system, and all the macroscopic quantities are weighted averages of the distribution function. The information contained in the Boltzmann equation is surprisingly rich, and the Euler and Navier-Stokes equations of fluid dynamics can be derived from it using series expansions. Moreover, the Boltzmann equation can reach regimes far from the capabilities of fluid dynamical equations, such as the realm of rarefied gases---the topic of this thesis. Although the Boltzmann equation is very powerful, it is extremely difficult to solve in most situations. Thus the only hope is to solve it numerically. But soon one finds that even a numerical simulation of the equation is extremely difficult, due to both the complex and high-dimensional integral in the collision operator, and the hyperbolic phase-space advection terms. For this reason, until few years ago most numerical simulations had to rely on Monte Carlo techniques. In this thesis I will present a new and robust numerical scheme to compute direct deterministic solutions of the Boltzmann equation, and I will use it to explore some classical gas-dynamical problems. In particular, I will study in detail one of the most famous and intrinsically nonlinear problems in rarefied gas dynamics, namely the accurate determination of the Boltzmann shock profile for a gas of hard spheres.
LOTUS 1-2-3-BASED SYSTEM FOR RECORDING AND MAINTAINING BODY WEIGHT OF LABORATORY ANIMALS
Body weight maintenance is required in a variety of behavioral and physiological studies. C-based animal weighing system is described which features automated data collection and allows for accurate control of body weight in test animals via manipulation of food intake. ajor syst...
Dietary adherence during weight loss predicts weight regain.
Del Corral, Pedro; Bryan, David R; Garvey, W Timothy; Gower, Barbara A; Hunter, Gary R
2011-06-01
This study examined the relationship between previous dietary adherence during a low-calorie diet weight loss intervention and subsequent weight change during a 2-year follow-up for weight maintenance. One hundred and sixteen healthy, recently weight reduced (lost ~12 kg, BMI 22-25 kg/m2) premenopausal women were studied. Dietary adherence was assessed by doubly labeled water (DLW) and body composition change. Comparisons were made between the upper and lower tertiles for previous dietary adherence and subsequent weight change at 1- and 2-year follow-up. Percent weight regained was significantly lower (30.9 ± 6.7% vs. 66.7 ± 9.4%; P < 0.05) in the upper compared to the lower adherence tertile for previous weight loss dietary adherence (49.9 ± 8.8% vs. 96.8 ± 12.8% P < 0.05) at 1- and 2-year follow-up, respectively. This difference was partly explained by increases in daily activity-related energy expenditure (AEE) (+95 ± 45 kcal/day vs. -44 ± 42 kcal/day, P < 0.05) and lower daily energy intake (2,066 ± 71 kcal/day vs. 2,289 ± 62 kcal/day, P < 0.05) in the higher tertile for previous dietary adherence, compared to the lower. These findings suggest that higher adherence (i.e., higher tertile) to the previous low-calorie diet predicts lower weight regain over 2-year follow-up for weight maintenance, which is explained by lower energy intake and higher physical activity. Finally, how well an individual adheres to a low-calorie diet intervention during weight loss may be a useful tool for identifying individuals who are particularly vulnerable to subsequent weight regain. PMID:21164500
The weighted random graph model
NASA Astrophysics Data System (ADS)
Garlaschelli, Diego
2009-07-01
We introduce the weighted random graph (WRG) model, which represents the weighted counterpart of the Erdos-Renyi random graph and provides fundamental insights into more complicated weighted networks. We find analytically that the WRG is characterized by a geometric weight distribution, a binomial degree distribution and a negative binomial strength distribution. We also characterize exactly the percolation phase transitions associated with edge removal and with the appearance of weighted subgraphs of any order and intensity. We find that even this completely null model displays a percolation behaviour similar to what is observed in real weighted networks, implying that edge removal cannot be used to detect community structure empirically. By contrast, the analysis of clustering successfully reveals different patterns between the WRG and real networks.
Socioeconomic Disparities in Emerging Adult Weight and Weight Behaviors
ERIC Educational Resources Information Center
VanKim, Nicole A.; Laska, Melissa N.
2012-01-01
Objectives: To explore weight, weight behaviors, and tobacco and alcohol use among emerging adults by parental education and financial strain. Methods: Cross-sectional analyses of 2010 survey data from an urban Minnesota public 4-year university and 2-year community college (n=1201). Results: Low parental education was associated with lower…
Molecular Weight and Molecular Weight Distributions in Synthetic Polymers.
ERIC Educational Resources Information Center
Ward, Thomas Carl
1981-01-01
Focuses on molecular weight and molecular weight distributions (MWD) and models for predicting MWD in a pedagogical way. In addition, instrumental methods used to characterize MWD are reviewed with emphasis on physical chemistry of each, including end-group determination, osmometry, light scattering, solution viscosity, fractionation, and…
The Healthy Weight Collaborative: quality improvement methods promoting healthy weight.
McPherson, Marianne E; Vanderkruik, Rachel; Reims, Kathy; Coulouris, Natasha; Anand, Shikha; Linde-Feucht, Sarah; Homer, Charles J
2012-08-01
Promoting healthy weight requires innovative approaches and a concerted response across all sectors of society. This commentary features the framework guiding the Healthy Weight Collaborative, a two-phased quality improvement (QI) learning collaborative and key activity of the Collaborate for Healthy Weight initiative. Multi-sector teams from primary care, public health, and community-based organizations use QI to identify, test, and implement program and policy changes in their communities related to promoting healthy weight. We describe the Collaborative's overall design based on the Action Model to Achieve Healthy People 2020 Goals and our approach of applying QI methods to advance implementation of sustainable ways to promote healthy weight and healthy equity. We provide specifics on measurement and change strategies as well as examples of Plan-Do-Study-Act cycles from teams participating in Phase 1 of the Collaborative. These teams will serve as leaders for sustainable, positive change in their communities. PMID:22864485
Measurement of residual stresses using fracture mechanics weight functions
Fan, Y.
2000-10-01
A residual stress measurement method has been developed to quantify through-the-thickness residual stresses. Accurate measurement of residual stresses is crucial for many engineering structures. Fabrication processes such as welding and machining generate residual stresses that are difficult to predict. Residual stresses affect the integrity of structures through promoting failures due to brittle fracture, fatigue, stress corrosion cracking, and wear. In this work, the weight function theory of fracture mechanics is used to measure residual stresses. The weight function theory is an important development in computational fracture mechanics. Stress intensity factors for arbitrary stress distribution on the crack faces can be accurately and efficiently computed for predicting crack growth. This paper demonstrates that the weight functions are equally useful in measuring residual stresses. In this method, an artificial crack is created by a thin cut in a structure containing residual stresses. The cut relieves the residual stresses normal to the crack-face and allows the relieved residual stresses to deform the structure. Strain gages placed adjacent to the cut measure the relieved strains corresponding to incrementally increasing depths of the cut. The weight functions of the cracked body relate the measured strains to the residual stresses normal to the cut within the structure. The procedure details, such as numerical integration of the singular functions in applying the weight function method, will be discussed.
Weighted contrast metric for imaging system performance
NASA Astrophysics Data System (ADS)
Teaney, Brian P.
2012-06-01
There have been significant improvements in the image quality metrics used in the NVESD model suite in recent years. The introduction of the Targeting Task Performance (TTP) metric to replace the Johnson criteria yielded significantly more accurate predictions for under-sampled imaging systems in particular. However, there are certain cases which cause the TTP metric to predict optimistic performance. In this paper a new metric for predicting performance of imaging systems is described. This new weighted contrast metric is characterized as a hybrid of the TTP metric and Johnson criteria. Results from a number of historical perception studies are presented to compare the performance of the TTP metric and Johnson criteria to the newly proposed metric.
Validation of an Improved Pediatric Weight Estimation Strategy
Abdel-Rahman, Susan M.; Ahlers, Nichole; Holmes, Anne; Wright, Krista; Harris, Ann; Weigel, Jaylene; Hill, Talita; Baird, Kim; Michaels, Marla; Kearns, Gregory L.
2013-01-01
OBJECTIVES To validate the recently described Mercy method for weight estimation in an independent cohort of children living in the United States. METHODS Anthropometric data including weight, height, humeral length, and mid upper arm circumference were collected from 976 otherwise healthy children (2 months to 14 years old). The data were used to examine the predictive performances of the Mercy method and four other weight estimation strategies (the Advanced Pediatric Life Support [APLS] method, the Broselow tape, and the Luscombe and Owens and the Nelson methods). RESULTS The Mercy method demonstrated accuracy comparable to that observed in the original study (mean error: −0.3 kg; mean percentage error: −0.3%; root mean square error: 2.62 kg; 95% limits of agreement: 0.83–1.19). This method estimated weight within 20% of actual for 95% of children compared with 58.7% for APLS, 78% for Broselow, 54.4% for Luscombe and Owens, and 70.4% for Nelson. Furthermore, the Mercy method was the only weight estimation strategy which enabled prediction of weight in all of the children enrolled. CONCLUSIONS The Mercy method proved to be highly accurate and more robust than existing weight estimation strategies across a wider range of age and body mass index values, thereby making it superior to other existing approaches. PMID:23798905
Nutrition, Weight Control, and Exercise.
ERIC Educational Resources Information Center
Katch, Frank I.; McArdle, William D.
This book contains information on nutrition, weight control, and exercise. Some basic information from the biological sciences is included but a specialized background is not necessary to understand the text. The content is appropriate for nutrition, weight control, exercise, and physical fitness courses at the university level, for the various…
Predictors of successful weight loss
Technology Transfer Automated Retrieval System (TEKTRAN)
The identification of variables in the early stages of treatment that are related to successful weight loss provides practitioners with important information. These factors may be assessed to determine the likelihood of future success. Weight loss at the beginning of treatment, depressive symptomato...
Weight Perceptions, Misperceptions, and Dating Violence Victimization Among U.S. Adolescents
Farhat, Tilda; Haynie, Denise; Summersett-Ringgold, Faith; Brooks-Russell, Ashley; Iannotti, Ronald J.
2015-01-01
Dating violence is a major public health issue among youth. Overweight/obese adolescents experience peer victimization and discrimination and may be at increased risk of dating violence victimization. Furthermore, given the stigma associated with overweight/obesity, perceptions and misperceptions of overweight may be more important than actual weight status for dating violence victimization. This study examines the association of three weight indices (weight status, perceived weight, and weight perception accuracy) with psychological and physical dating violence victimization. The 2010 baseline survey of the 7-year NEXT Generation Health Study used a three-stage stratified clustered sampling design to select a nationally representative sample of U.S. 10th-grade students (n = 1,983). Participants who have had a boyfriend/girlfriend reported dating violence victimization and perceived weight. Weight status was computed from measured height/weight. Weight perception accuracy (accurate/underestimate/overestimate) was calculated by comparing weight status and perceived weight. Gender-stratified regressions examined the association of weight indices and dating violence victimization. Racial/ethnic differences were also examined. The association of weight indices with dating violence victimization significantly differed by gender. Overall, among boys, no associations were observed. Among girls, weight status was not associated with dating violence victimization, nor with number of dating violence victimization acts; however, perceived weight and weight perception accuracy were significantly associated with dating violence victimization, type of victimization, and number of victimization acts. Post hoc analyses revealed significant racial/ethnic differences. White girls who perceive themselves (accurately or not) to be overweight, and Hispanic girls who are overweight, may be at increased risk of dating violence victimization. These findings suggest a targeted approach to
Weight perceptions, misperceptions, and dating violence victimization among U.S. adolescents.
Farhat, Tilda; Haynie, Denise; Summersett-Ringgold, Faith; Brooks-Russell, Ashley; Iannotti, Ronald J
2015-05-01
Dating violence is a major public health issue among youth. Overweight/obese adolescents experience peer victimization and discrimination and may be at increased risk of dating violence victimization. Furthermore, given the stigma associated with overweight/obesity, perceptions and misperceptions of overweight may be more important than actual weight status for dating violence victimization. This study examines the association of three weight indices (weight status, perceived weight, and weight perception accuracy) with psychological and physical dating violence victimization. The 2010 baseline survey of the 7-year NEXT Generation Health Study used a three-stage stratified clustered sampling design to select a nationally representative sample of U.S. 10th-grade students (n = 1,983). Participants who have had a boyfriend/girlfriend reported dating violence victimization and perceived weight. Weight status was computed from measured height/weight. Weight perception accuracy (accurate/underestimate/overestimate) was calculated by comparing weight status and perceived weight. Gender-stratified regressions examined the association of weight indices and dating violence victimization. Racial/ethnic differences were also examined. The association of weight indices with dating violence victimization significantly differed by gender. Overall, among boys, no associations were observed. Among girls, weight status was not associated with dating violence victimization, nor with number of dating violence victimization acts; however, perceived weight and weight perception accuracy were significantly associated with dating violence victimization, type of victimization, and number of victimization acts. Post hoc analyses revealed significant racial/ethnic differences. White girls who perceive themselves (accurately or not) to be overweight, and Hispanic girls who are overweight, may be at increased risk of dating violence victimization. These findings suggest a targeted approach to
Fungible weights in logistic regression.
Jones, Jeff A; Waller, Niels G
2016-06-01
In this article we develop methods for assessing parameter sensitivity in logistic regression models. To set the stage for this work, we first review Waller's (2008) equations for computing fungible weights in linear regression. Next, we describe 2 methods for computing fungible weights in logistic regression. To demonstrate the utility of these methods, we compute fungible logistic regression weights using data from the Centers for Disease Control and Prevention's (2010) Youth Risk Behavior Surveillance Survey, and we illustrate how these alternate weights can be used to evaluate parameter sensitivity. To make our work accessible to the research community, we provide R code (R Core Team, 2015) that will generate both kinds of fungible logistic regression weights. (PsycINFO Database Record PMID:26651981
Perceived Weight Discrimination and Obesity
Sutin, Angelina R.; Terracciano, Antonio
2013-01-01
Weight discrimination is prevalent in American society. Although associated consistently with psychological and economic outcomes, less is known about whether weight discrimination is associated with longitudinal changes in obesity. The objectives of this research are (1) to test whether weight discrimination is associated with risk of becoming obese (Body Mass Index≥30; BMI) by follow-up among those not obese at baseline, and (2) to test whether weight discrimination is associated with risk of remaining obese at follow-up among those already obese at baseline. Participants were drawn from the Health and Retirement Study, a nationally representative longitudinal survey of community-dwelling US residents. A total of 6,157 participants (58.6% female) completed the discrimination measure and had weight and height available from the 2006 and 2010 assessments. Participants who experienced weight discrimination were approximately 2.5 times more likely to become obese by follow-up (OR = 2.54, 95% CI = 1.58–4.08) and participants who were obese at baseline were three times more likely to remain obese at follow up (OR = 3.20, 95% CI = 2.06–4.97) than those who had not experienced such discrimination. These effects held when controlling for demographic factors (age, sex, ethnicity, education) and when baseline BMI was included as a covariate. These effects were also specific to weight discrimination; other forms of discrimination (e.g., sex, race) were unrelated to risk of obesity at follow-up. The present research demonstrates that, in addition to poorer mental health outcomes, weight discrimination has implications for obesity. Rather than motivating individuals to lose weight, weight discrimination increases risk for obesity. PMID:23894586
Code of Federal Regulations, 2010 CFR
2010-07-01
... individual's baseline weight, sustained for three months or longer; and the term “minor weight loss” means a weight loss of 10 to 20 percent of the individual's baseline weight, sustained for three months or...
Selecting a Weight-Loss Program
... Weight Tip Choose weight-loss programs that encourage healthy behaviors that help you lose weight gradually and maintain your weight over time. Looking for easy-to-use information for eating healthy on the go? The Maintaining a Healthy ...
Weighting climate model projections using observational constraints
Gillett, Nathan P.
2015-01-01
Projected climate change integrates the net response to multiple climate feedbacks. Whereas existing long-term climate change projections are typically based on unweighted individual climate model simulations, as observed climate change intensifies it is increasingly becoming possible to constrain the net response to feedbacks and hence projected warming directly from observed climate change. One approach scales simulated future warming based on a fit to observations over the historical period, but this approach is only accurate for near-term projections and for scenarios of continuously increasing radiative forcing. For this reason, the recent Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5) included such observationally constrained projections in its assessment of warming to 2035, but used raw model projections of longer term warming to 2100. Here a simple approach to weighting model projections based on an observational constraint is proposed which does not assume a linear relationship between past and future changes. This approach is used to weight model projections of warming in 2081–2100 relative to 1986–2005 under the Representative Concentration Pathway 4.5 forcing scenario, based on an observationally constrained estimate of the Transient Climate Response derived from a detection and attribution analysis. The resulting observationally constrained 5–95% warming range of 0.8–2.5 K is somewhat lower than the unweighted range of 1.1–2.6 K reported in the IPCC AR5. PMID:26438283
Technology Transfer Automated Retrieval System (TEKTRAN)
The objective of our study was to determine the impact of grade of obesity on weight-loss outcomes of a community-based, intensive behavioral counseling program (Weight Watchers Points-Plus). Previous studies have shown that individuals with a higher body mass index (BMI) at the beginning of treatme...
Rapid Weight Loss in Sports with Weight Classes.
Khodaee, Morteza; Olewinski, Lucianne; Shadgan, Babak; Kiningham, Robert R
2015-01-01
Weight-sensitive sports are popular among elite and nonelite athletes. Rapid weight loss (RWL) practice has been an essential part of many of these sports for many decades. Due to the limited epidemiological studies on the prevalence of RWL, its true prevalence is unknown. It is estimated that more than half of athletes in weight-class sports have practiced RWL during the competitive periods. As RWL can have significant physical, physiological, and psychological negative effects on athletes, its practice has been discouraged for many years. It seems that appropriate rule changes have had the biggest impact on the practice of RWL in sports like wrestling. An individualized and well-planned gradual and safe weight loss program under the supervision of a team of coaching staff, athletic trainers, sports nutritionists, and sports physicians is recommended. PMID:26561763
Correlates of Low Birth Weight
Hazarika, Jayant; Dutta, Sudip
2014-01-01
Background. Low birth weight is the single most important factor that determines the chances of child survival. A recent annual estimation indicated that nearly 8 million infants are born with low birth weight in India. The infant mortality rate is about 20 times greater for all low birth weight babies. Methods. A matched case–control study was conducted on 130 low birth weight babies and 130 controls for 12 months (from August 1, 2007, to July 31, 2008) at the Central Referral Hospital, Tadong, East District of Sikkim, India. Data were analyzed using the Statistical Package for Social Sciences, version 10.0 for Windows. Chi-square test and multiple logistic regression were applied. A P value less than .05 was considered as significant. Results. In the first phase of this study, 711 newborn babies, borne by 680 mothers, were screened at the Central Referral Hospital of Sikkim during the 1-year study period, and the proportion of low birth weight babies was determined to be 130 (18.3%). Conclusion. Multiple logistic regression analysis, conducted in the second phase, revealed that low or middle socioeconomic status, maternal underweight, twin pregnancy, previous history of delivery of low birth weight babies, smoking and consumption of alcohol during pregnancy, and congenital anomalies had independent significant association with low birth weight in this study population.
Atomic weights in gas analysis
NASA Astrophysics Data System (ADS)
van der Veen, Adriaan M. H.; Hafner, Katarina
2014-02-01
The publication of the standard atomic weights of 2009 by IUPAC raised the question of to what extent these changes affect the calculated composition of reference and calibration gas mixtures and the associated measurement uncertainty. The smallest uncertainties are attainable in the gravimetric gas mixture preparation, so the assessment was made for this technique. For the first time, the uncertainty contributions to the overall budget due to weighing, molecular weights, and composition of the parent gases are reported separately. The calculations show that even with the standard atomic weights of 2007, the uncertainty contribution due to the molecular weights can be of the same order as that due to weighing. The standard atomic weights of 2009 and 2011, when used under the same assumptions, increase the uncertainties of the amount-of-substance fractions of the abundant components from high-purity parent gases sometimes appreciably. Based on these calculations and the fact that the atomic weight intervals include sources that are unlikely to be generally relevant for measurements supporting trade, commerce, health and safety, there is a need to make a more in-depth analysis of the atomic weights used in calculations, and to reflect the knowledge about the isotopic composition of relevant materials in the value assignment and uncertainty calculation.
Cook, Andrea J.; Elmore, Joann G.; Zhu, Weiwei; Jackson, Sara L.; Carney, Patricia A.; Flowers, Chris; Onega, Tracy; Geller, Berta; Rosenberg, Robert D.; Miglioretti, Diana L.
2013-01-01
Objective To determine if U.S. radiologists accurately estimate their own interpretive performance of screening mammography and how they compare their performance to their peers’. Materials and Methods 174 radiologists from six Breast Cancer Surveillance Consortium (BCSC) registries completed a mailed survey between 2005 and 2006. Radiologists’ estimated and actual recall, false positive, and cancer detection rates and positive predictive value of biopsy recommendation (PPV2) for screening mammography were compared. Radiologists’ ratings of their performance as lower, similar, or higher than their peers were compared to their actual performance. Associations with radiologist characteristics were estimated using weighted generalized linear models. The study was approved by the institutional review boards of the participating sites, informed consent was obtained from radiologists, and procedures were HIPAA compliant. Results While most radiologists accurately estimated their cancer detection and recall rates (74% and 78% of radiologists), fewer accurately estimated their false positive rate and PPV2 (19% and 26%). Radiologists reported having similar (43%) or lower (31%) recall rates and similar (52%) or lower (33%) false positive rates compared to their peers, and similar (72%) or higher (23%) cancer detection rates and similar (72%) or higher (38%) PPV2. Estimation accuracy did not differ by radiologists’ characteristics except radiologists who interpret ≤1,000 mammograms annually were less accurate at estimating their recall rates. Conclusion Radiologists perceive their performance to be better than it actually is and at least as good as their peers. Radiologists have particular difficulty estimating their false positive rates and PPV2. PMID:22915414
Supplier Selection Using Weighted Utility Additive Method
NASA Astrophysics Data System (ADS)
Karande, Prasad; Chakraborty, Shankar
2015-10-01
Supplier selection is a multi-criteria decision-making (MCDM) problem which mainly involves evaluating a number of available suppliers according to a set of common criteria for choosing the best one to meet the organizational needs. For any manufacturing or service organization, selecting the right upstream suppliers is a key success factor that will significantly reduce purchasing cost, increase downstream customer satisfaction and improve competitive ability. The past researchers have attempted to solve the supplier selection problem employing different MCDM techniques which involve active participation of the decision makers in the decision-making process. This paper deals with the application of weighted utility additive (WUTA) method for solving supplier selection problems. The WUTA method, an extension of utility additive approach, is based on ordinal regression and consists of building a piece-wise linear additive decision model from a preference structure using linear programming (LP). It adopts preference disaggregation principle and addresses the decision-making activities through operational models which need implicit preferences in the form of a preorder of reference alternatives or a subset of these alternatives present in the process. The preferential preorder provided by the decision maker is used as a restriction of a LP problem, which has its own objective function, minimization of the sum of the errors associated with the ranking of each alternative. Based on a given reference ranking of alternatives, one or more additive utility functions are derived. Using these utility functions, the weighted utilities for individual criterion values are combined into an overall weighted utility for a given alternative. It is observed that WUTA method, having a sound mathematical background, can provide accurate ranking to the candidate suppliers and choose the best one to fulfill the organizational requirements. Two real time examples are illustrated to prove
Efficient implementation of weighted ENO schemes
NASA Technical Reports Server (NTRS)
Jiang, Guang-Shan; Shu, Chi-Wang
1995-01-01
In this paper, we further analyze, test, modify and improve the high order WENO (weighted essentially non-oscillatory) finite difference schemes of Liu, Osher and Chan. It was shown by Liu et al. that WENO schemes constructed from the r-th order (in L1 norm) ENO schemes are (r+1)-th order accurate. We propose a new way of measuring the smoothness of a numerical solution, emulating the idea of minimizing the total variation of the approximation, which results in a 5-th order WENO scheme for the case r = 3, instead of the 4-th order with the original smoothness measurement by Liu et al. This 5-th order WENO scheme is as fast as the 4-th order WENO scheme of Liu et al., and both schemes are about twice as fast as the 4-th order ENO schemes on vector supercomputers and as fast on serial and parallel computers. For Euler systems of gas dynamics, we suggest computing the weights from pressure and entropy instead of the characteristic values to simplify the costly characteristic procedure. The resulting WENO schemes are about twice as fast as the WENO schemes using the characteristic decompositions to compute weights, and work well for problems which do not contain strong shocks or strong reflected waves. We also prove that, for conservation laws with smooth solutions, all WENO schemes are convergent. Many numerical tests, including the 1D steady state nozzle flow problem and 2D shock entropy wave interaction problem, are presented to demonstrate the remarkable capability of the WENO schemes, especially the WENO scheme using the new smoothness measurement, in resolving complicated shock and flow structures. We have also applied Yang's artificial compression method to the WENO schemes to sharpen contact discontinuities.
Judging body weight from faces: the height-weight illusion.
Schneider, Tobias M; Hecht, Heiko; Carbon, Claus-Christian
2012-01-01
Being able to exploit features of the human face to predict health and fitness can serve as an evolutionary advantage. Surface features such as facial symmetry, averageness, and skin colour are known to influence attractiveness. We sought to determine whether observers are able to extract more complex features, namely body weight. If possible, it could be used as a predictor for health and fitness. For instance, facial adiposity could be taken to indicate a cardiovascular challenge or proneness to infections. Observers seem to be able to glean body weight information from frontal views of a face. Is weight estimation robust across different viewing angles? We showed that participants strongly overestimated body weight for faces photographed from a lower vantage point while underestimating it for faces photographed from a higher vantage point. The perspective distortions of simple facial measures (e.g., width-to-height ratio) that accompany changes in vantage point do not suffice to predict body weight. Instead, more complex patterns must be involved in the height-weight illusion. PMID:22611670
Accurate bulk density determination of irregularly shaped translucent and opaque aerogels
NASA Astrophysics Data System (ADS)
Petkov, M. P.; Jones, S. M.
2016-05-01
We present a volumetric method for accurate determination of bulk density of aerogels, calculated from extrapolated weight of the dry pure solid and volume estimates based on the Archimedes' principle of volume displacement, using packed 100 μm-sized monodispersed glass spheres as a "quasi-fluid" media. Hard particle packing theory is invoked to demonstrate the reproducibility of the apparent density of the quasi-fluid. Accuracy rivaling that of the refractive index method is demonstrated for both translucent and opaque aerogels with different absorptive properties, as well as for aerogels with regular and irregular shapes.
Accurate body composition measures from whole-body silhouettes
Xie, Bowen; Avila, Jesus I.; Ng, Bennett K.; Fan, Bo; Loo, Victoria; Gilsanz, Vicente; Hangartner, Thomas; Kalkwarf, Heidi J.; Lappe, Joan; Oberfield, Sharon; Winer, Karen; Zemel, Babette; Shepherd, John A.
2015-01-01
Purpose: Obesity and its consequences, such as diabetes, are global health issues that burden about 171 × 106 adult individuals worldwide. Fat mass index (FMI, kg/m2), fat-free mass index (FFMI, kg/m2), and percent fat mass may be useful to evaluate under- and overnutrition and muscle development in a clinical or research environment. This proof-of-concept study tested whether frontal whole-body silhouettes could be used to accurately measure body composition parameters using active shape modeling (ASM) techniques. Methods: Binary shape images (silhouettes) were generated from the skin outline of dual-energy x-ray absorptiometry (DXA) whole-body scans of 200 healthy children of ages from 6 to 16 yr. The silhouette shape variation from the average was described using an ASM, which computed principal components for unique modes of shape. Predictive models were derived from the modes for FMI, FFMI, and percent fat using stepwise linear regression. The models were compared to simple models using demographics alone [age, sex, height, weight, and body mass index z-scores (BMIZ)]. Results: The authors found that 95% of the shape variation of the sampled population could be explained using 26 modes. In most cases, the body composition variables could be predicted similarly between demographics-only and shape-only models. However, the combination of shape with demographics improved all estimates of boys and girls compared to the demographics-only model. The best prediction models for FMI, FFMI, and percent fat agreed with the actual measures with R2 adj. (the coefficient of determination adjusted for the number of parameters used in the model equation) values of 0.86, 0.95, and 0.75 for boys and 0.90, 0.89, and 0.69 for girls, respectively. Conclusions: Whole-body silhouettes in children may be useful to derive estimates of body composition including FMI, FFMI, and percent fat. These results support the feasibility of measuring body composition variables from simple
Weight Estimation Tool for Children Aged 6 to 59 Months in Limited-Resource Settings
2016-01-01
Importance A simple, reliable anthropometric tool for rapid estimation of weight in children would be useful in limited-resource settings where current weight estimation tools are not uniformly reliable, nearly all global under-five mortality occurs, severe acute malnutrition is a significant contributor in approximately one-third of under-five mortality, and a weight scale may not be immediately available in emergencies to first-response providers. Objective To determine the accuracy and precision of mid-upper arm circumference (MUAC) and height as weight estimation tools in children under five years of age in low-to-middle income countries. Design This was a retrospective observational study. Data were collected in 560 nutritional surveys during 1992–2006 using a modified Expanded Program of Immunization two-stage cluster sample design. Setting Locations with high prevalence of acute and chronic malnutrition. Participants A total of 453,990 children met inclusion criteria (age 6–59 months; weight ≤ 25 kg; MUAC 80–200 mm) and exclusion criteria (bilateral pitting edema; biologically implausible weight-for-height z-score (WHZ), weight-for-age z-score (WAZ), and height-for-age z-score (HAZ) values). Exposures Weight was estimated using Broselow Tape, Hong Kong formula, and database MUAC alone, height alone, and height and MUAC combined. Main Outcomes and Measures Mean percentage difference between true and estimated weight, proportion of estimates accurate to within ± 25% and ± 10% of true weight, weighted Kappa statistic, and Bland-Altman bias were reported as measures of tool accuracy. Standard deviation of mean percentage difference and Bland-Altman 95% limits of agreement were reported as measures of tool precision. Results Database height was a more accurate and precise predictor of weight compared to Broselow Tape 2007 [B], Broselow Tape 2011 [A], and MUAC. Mean percentage difference between true and estimated weight was +0.49% (SD = 10
... Smoking - Eating Well and Losing Weight • Tools & Resources Sodium & High Blood Pressure Popular Articles 1 Understanding Blood Pressure Readings 2 Sodium and Salt 3 All About Heart Rate (Pulse) ...
Apparatus for molecular weight separation
Smith, Richard D.; Liu, Chuanliang
2001-01-01
The present invention relates generally to an apparatus and method for separating high molecular weight molecules from low molecular weight molecules. More specifically, the invention relates to the use of microdialysis for removal of the salt (low molecular weight molecules) from a nucleotide sample (high molecular weight molecules) for ESI-MS analysis. The dialysis or separation performance of the present invention is improved by (1) increasing dialysis temperature thereby increasing desalting efficiency and improving spectrum quality; (2) adding piperidine and imidazole to the dialysis buffer solution and reducing charge states and further increasing detection sensitivity for DNA; (3) using low concentrations (0-2.5 mM NH4OAc) of dialysis buffer and shifting the DNA negative ions to higher charge states, producing a nearly 10-fold increase in detection sensitivity and a slightly decreased desalting efficiency, (4) conducting a two-stage separation or (5) any combination of (1), (2), (3) and (4).
78 FR 34604 - Submitting Complete and Accurate Information
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-10
... COMMISSION 10 CFR Part 50 Submitting Complete and Accurate Information AGENCY: Nuclear Regulatory Commission... accurate information as would a licensee or an applicant for a license.'' DATES: Submit comments by August... may submit comments by any of the following methods (unless this document describes a different...
Tube dimpling tool assures accurate dip-brazed joints
NASA Technical Reports Server (NTRS)
Beuyukian, C. S.; Heisman, R. M.
1968-01-01
Portable, hand-held dimpling tool assures accurate brazed joints between tubes of different diameters. Prior to brazing, the tool performs precise dimpling and nipple forming and also provides control and accurate measuring of the height of nipples and depth of dimples so formed.
31 CFR 205.24 - How are accurate estimates maintained?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false How are accurate estimates maintained... Treasury-State Agreement § 205.24 How are accurate estimates maintained? (a) If a State has knowledge that an estimate does not reasonably correspond to the State's cash needs for a Federal assistance...
Birth weight pattern in Karnataka.
Prasad, K N; Rao, R S; Sujatha, A
1994-07-01
The pattern of birth weight is described among births recorded in rural maternity homes in coastal areas of Udupi taluk in South Kanara district in Karnataka state, India. Literacy of the study area was 78.5%, and female literacy was 73.0%. The mean age at marriage was 21.4 years. Over 90% of mothers received some prenatal care. Contraceptive prevalence was 43%. The study area had six rural maternity homes that each served a population of about 10,000 people. The homes were well equipped with trained nurse-midwives, medical rooms, and equipment, and were connected by roads and telephones with Kasturba Hospital. High risk cases were transported by air to Kasturba Hospital. Birth weight was recorded with a UNICEF infant lever balance scale within one hour of delivery. Between July 1985 and June 1988, 4498 singleton live births were recorded: 2308 (51.3%) boys and 2190 (48.7%) girls. 80% weighed between 2500 and 3400 g. 13.3% were low birth weight of under 2500 g, and 0.4% were very low birth weight of under 1500 g. The mean birth weight was 2823 g: 2850 g for boys and 2765.4 for girls. The mean birth weight increased with maternal age; it also increased with increased parity and increased gestation age. The lowest birth weight of 2767.7 g occurred among first births; the highest of 2897.6 g was among births to women with multiple births. 91.3% were born between 37-40 weeks, and 7.5% were preterm. There were statistically significant differences in the mean birth weights by gender. 9.1% of births were to teenagers, and 69% of mothers were 20-29 years old. 30% of births were first births, and 51% were second and third births. The small family norm appeared to be accepted by this study population. PMID:7890348
Financial Incentives and Weight Control
Jeffery, Robert W.
2012-01-01
This paper reviews research studies evaluating the use of financial incentives to promote weight control conducted between 1972 and 2010. It provides an overview of behavioral theories pertaining to incentives and describes empirical studies evaluating specific aspects of incentives. Research on financial incentives and weight control has a history spanning more than 30 years. Early studies were guided by operant learning concepts from Psychology, while more recent studies have relied on economic theory. Both theoretical orientations argue that providing financial rewards for losing weight should motivate people to engage in behaviors that produce weight loss. Empirical research has strongly supported this idea. However, results vary widely due to differences in incentive size and schedule, as well as contextual factors. Thus, many important questions about the use of incentives have not yet been clearly answered. Weight-maintenance studies using financial incentives are particularly sparse, so that their long-term efficacy and thus, value in addressing the public health problem of obesity is unclear. Major obstacles to sustained applications of incentive in weight control are funding sources and acceptance by those who might benefit. PMID:22244800
Radioactive Elements in the Standard Atomic Weights Table.
Holden,N.E.
2007-08-04
In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition
Intention, perceived control, and weight loss: an application of the theory of planned behavior.
Schifter, D E; Ajzen, I
1985-09-01
Success at attempted weight reduction among college women was predicted on the basis of a theory of planned behavior. At the beginning of a 6-week period, participants expressed their attitudes, subjective norms, perceived control, and intentions with respect to losing weight. In addition, the extent to which they had made detailed weight reduction plans was assessed, as were a number of general attitudes and personality factors. In support of the theory, intentions to lose weight were accurately predicted on the basis of attitudes, subjective norms, and perceived control; perceived control and intentions were together moderately successful in predicting the amount of weight that participants actually lost over the 6-week period. Actual weight loss was also found to increase with development of a plan and with ego strength, factors that were assumed to increase control over goal attainment. Other factors, such as health locus of control, perceived competence, and action control, were found to be unrelated to weight reduction. PMID:4045706
Evaluation of node importance based on topological potential in weighted complex networks
NASA Astrophysics Data System (ADS)
Sun, Rui; Mu, A.-Li; Li, Lin; Zhong, Mi
2011-12-01
The unweighted networks only reflect the connection type between nodes and the network topology characteristics, by contrast, the weighted networks could describe the strength of interaction between nodes. For this reason, the weighted networks will give a better understanding of the characteristics of real-world networks and the complicated features of complex systems. The evaluation of node importance is a very meaningful research in weighted complex networks. This paper analyze the characteristics of weighted complex network and consider the effects of edge weights for the evaluation of node importance, introduces the idea of data field in theoretical physics and establishes the evaluation model of node importance in weighted complex network. Through the theoretical and experimental analysis, it is proved that this method can evaluate the importance of node in weighted complex network in a fast and accurate way, which is significant both to theory and practice.
Evaluation of node importance based on topological potential in weighted complex networks
NASA Astrophysics Data System (ADS)
Sun, Rui; Mu, A.-li; Li, Lin; Zhong, Mi
2012-01-01
The unweighted networks only reflect the connection type between nodes and the network topology characteristics, by contrast, the weighted networks could describe the strength of interaction between nodes. For this reason, the weighted networks will give a better understanding of the characteristics of real-world networks and the complicated features of complex systems. The evaluation of node importance is a very meaningful research in weighted complex networks. This paper analyze the characteristics of weighted complex network and consider the effects of edge weights for the evaluation of node importance, introduces the idea of data field in theoretical physics and establishes the evaluation model of node importance in weighted complex network. Through the theoretical and experimental analysis, it is proved that this method can evaluate the importance of node in weighted complex network in a fast and accurate way, which is significant both to theory and practice.
Epidemic spreading on complex networks with general degree and weight distributions
NASA Astrophysics Data System (ADS)
Wang, Wei; Tang, Ming; Zhang, Hai-Feng; Gao, Hui; Do, Younghae; Liu, Zong-Hua
2014-10-01
The spread of disease on complex networks has attracted wide attention in the physics community. Recent works have demonstrated that heterogeneous degree and weight distributions have a significant influence on the epidemic dynamics. In this study, a novel edge-weight-based compartmental approach is developed to estimate the epidemic threshold and epidemic size (final infected density) on networks with general degree and weight distributions, and a remarkable agreement with numerics is obtained. Even in complex networks with the strong heterogeneous degree and weight distributions, this approach is used. We then propose an edge-weight-based removal strategy with different biases and find that such a strategy can effectively control the spread of epidemic when the highly weighted edges are preferentially removed, especially when the weight distribution of a network is extremely heterogenous. The theoretical results from the suggested method can accurately predict the above removal effectiveness.
Application of 1H DOSY for Facile Measurement of Polymer Molecular Weights
Li, Weibin; Chung, Hoyong; Daeffler, Christopher; Johnson, Jeremiah A.; Grubbs, Robert H.
2012-01-01
To address the practical issues of polymer molecular weight determination, the first accurate polymer weight-average molecular weight determination method in diverse living/controlled polymerization via DOSY (diffusion-ordered NMR spectroscopy) is reported. Based on the linear correlation between the logarithm of diffusion coefficient (log D) and the molecular weights (log Mw), external calibration curves were created to give predictions of molecular weights of narrowly-dispersed polymers. This method was successfully applied to atom transfer radical polymerization (ATRP), reversible addition–fragmentation chain transfer (RAFT), and ring-opening metathesis polymerization (ROMP), with weight-average molecular weights given by this method closely correlated to those obtained from GPC measurement. PMID:23335819
Transport path optimization algorithm based on fuzzy integrated weights
NASA Astrophysics Data System (ADS)
Hou, Yuan-Da; Xu, Xiao-Hao
2014-11-01
Natural disasters cause significant damage to roads, making route selection a complicated logistical problem. To overcome this complexity, we present a method of using a trapezoidal fuzzy number to select the optimal transport path. Using the given trapezoidal fuzzy edge coefficients, we calculate a fuzzy integrated matrix, and incorporate the fuzzy multi-weights into fuzzy integrated weights. The optimal path is determined by taking two sets of vertices and transforming undiscovered vertices into discoverable ones. Our experimental results show that the model is highly accurate, and requires only a few measurement data to confirm the optimal path. The model provides an effective, feasible, and convenient method to obtain weights for different road sections, and can be applied to road planning in intelligent transportation systems.
The role of mass spectrometry in atomic weight determinations.
De Laeter, John R
2009-01-01
The 1914 Nobel Prize for Chemistry was awarded to Theodore Richards, whose work provided an insight into the history of the birth and evolution of matter as embedded in the atomic weights. However, the secret to unlocking the hieroglyphics contained in the atomic weights is revealed by a study of the relative abundances of the isotopes. A consistent set of internationally accepted atomic weights has been a goal of the scientific community for over a century. Atomic weights were originally determined by chemical stoichiometry--the so-called "Harvard Method," but this methodology has now been superseded by the "physical method," in which the isotopic composition and atomic masses of the isotopes comprising an element are used to calculate the atomic weight with far greater accuracy than before. The role of mass spectrometry in atomic weight determinations was initiated by the discovery of isotopes by Thomson, and established by the pioneering work of Aston, Dempster, and Nier using sophisticated mass spectrographs. The advent of the sector field mass spectrometer in 1947, revolutionized the application of mass spectrometry for both solids and gases to other fields of science including atomic weights. Subsequently, technological advances in mass spectrometry have enabled atomic masses to be determined with an accuracy better than one part in 10(7), whilst the absolute isotopic composition of many elements has been determined to produce accurate values of their atomic weights. Conversely, those same technological developments have revealed significant variations in the isotope abundances of many elements caused by a variety of physiochemical mechanisms in natural materials. Although these variations were initially seen as an impediment to the accuracy with which atomic weights could be determined, it was quickly realized that nature had provided a new tool to investigate physiochemical and biogeochemical mechanisms in nature, which could be exploited by precise and
Lenhart, Clare M; Daly, Brian P; Eichen, Dawn M
2011-12-01
Current evidence is equivocal as to whether adolescent's perception of weight status is linked to both healthy and risky behaviors. This study examined the association between accurate and inaccurate perception of weight and self-reported health and risk behaviors among a diverse sample of obese, urban adolescents. Data were analyzed from 1,180 participants in the 2009 Philadelphia Youth Risk Behavior Survey. Health behaviors of obese students self-identifying as very or slightly overweight were compared to obese students who underestimated their weight status. Accurate self-identifiers of weight status were significantly more likely to report trying to lose weight, bullying victimization, and suicide attempts as compared to obese students underestimating their weight status. Findings suggest that it is important for school nurses to understand that perceived weight status confers distinct risk profiles and differing needs for health-related services related to the physical, mental, and social health of adolescents. PMID:21976189
Factor weighting in DRASTIC modeling.
Pacheco, F A L; Pires, L M G R; Santos, R M B; Sanches Fernandes, L F
2015-02-01
Evaluation of aquifer vulnerability comprehends the integration of very diverse data, including soil characteristics (texture), hydrologic settings (recharge), aquifer properties (hydraulic conductivity), environmental parameters (relief), and ground water quality (nitrate contamination). It is therefore a multi-geosphere problem to be handled by a multidisciplinary team. The DRASTIC model remains the most popular technique in use for aquifer vulnerability assessments. The algorithm calculates an intrinsic vulnerability index based on a weighted addition of seven factors. In many studies, the method is subject to adjustments, especially in the factor weights, to meet the particularities of the studied regions. However, adjustments made by different techniques may lead to markedly different vulnerabilities and hence to insecurity in the selection of an appropriate technique. This paper reports the comparison of 5 weighting techniques, an enterprise not attempted before. The studied area comprises 26 aquifer systems located in Portugal. The tested approaches include: the Delphi consensus (original DRASTIC, used as reference), Sensitivity Analysis, Spearman correlations, Logistic Regression and Correspondence Analysis (used as adjustment techniques). In all cases but Sensitivity Analysis, adjustment techniques have privileged the factors representing soil characteristics, hydrologic settings, aquifer properties and environmental parameters, by leveling their weights to ≈4.4, and have subordinated the factors describing the aquifer media by downgrading their weights to ≈1.5. Logistic Regression predicts the highest and Sensitivity Analysis the lowest vulnerabilities. Overall, the vulnerability indices may be separated by a maximum value of 51 points. This represents an uncertainty of 2.5 vulnerability classes, because they are 20 points wide. Given this ambiguity, the selection of a weighting technique to integrate a vulnerability index may require additional
Weighted Watson-Crick automata
NASA Astrophysics Data System (ADS)
Tamrin, Mohd Izzuddin Mohd; Turaev, Sherzod; Sembok, Tengku Mohd Tengku
2014-07-01
There are tremendous works in biotechnology especially in area of DNA molecules. The computer society is attempting to develop smaller computing devices through computational models which are based on the operations performed on the DNA molecules. A Watson-Crick automaton, a theoretical model for DNA based computation, has two reading heads, and works on double-stranded sequences of the input related by a complementarity relation similar with the Watson-Crick complementarity of DNA nucleotides. Over the time, several variants of Watson-Crick automata have been introduced and investigated. However, they cannot be used as suitable DNA based computational models for molecular stochastic processes and fuzzy processes that are related to important practical problems such as molecular parsing, gene disease detection, and food authentication. In this paper we define new variants of Watson-Crick automata, called weighted Watson-Crick automata, developing theoretical models for molecular stochastic and fuzzy processes. We define weighted Watson-Crick automata adapting weight restriction mechanisms associated with formal grammars and automata. We also study the generative capacities of weighted Watson-Crick automata, including probabilistic and fuzzy variants. We show that weighted variants of Watson-Crick automata increase their generative power.
Weighted Watson-Crick automata
Tamrin, Mohd Izzuddin Mohd; Turaev, Sherzod; Sembok, Tengku Mohd Tengku
2014-07-10
There are tremendous works in biotechnology especially in area of DNA molecules. The computer society is attempting to develop smaller computing devices through computational models which are based on the operations performed on the DNA molecules. A Watson-Crick automaton, a theoretical model for DNA based computation, has two reading heads, and works on double-stranded sequences of the input related by a complementarity relation similar with the Watson-Crick complementarity of DNA nucleotides. Over the time, several variants of Watson-Crick automata have been introduced and investigated. However, they cannot be used as suitable DNA based computational models for molecular stochastic processes and fuzzy processes that are related to important practical problems such as molecular parsing, gene disease detection, and food authentication. In this paper we define new variants of Watson-Crick automata, called weighted Watson-Crick automata, developing theoretical models for molecular stochastic and fuzzy processes. We define weighted Watson-Crick automata adapting weight restriction mechanisms associated with formal grammars and automata. We also study the generative capacities of weighted Watson-Crick automata, including probabilistic and fuzzy variants. We show that weighted variants of Watson-Crick automata increase their generative power.
Accurate calculation of diffraction-limited encircled and ensquared energy.
Andersen, Torben B
2015-09-01
Mathematical properties of the encircled and ensquared energy functions for the diffraction-limited point-spread function (PSF) are presented. These include power series and a set of linear differential equations that facilitate the accurate calculation of these functions. Asymptotic expressions are derived that provide very accurate estimates for the relative amount of energy in the diffraction PSF that fall outside a square or rectangular large detector. Tables with accurate values of the encircled and ensquared energy functions are also presented. PMID:26368873
Fujita, Masahiro; Yajima, Tomonari; Iijima, Kazuaki; Sato, Kiyoshi
2012-05-01
The uncertainty in pesticide residue levels (UPRL) associated with sampling size was estimated using individual acetamiprid and cypermethrin residue data from preharvested apple, broccoli, cabbage, grape, and sweet pepper samples. The relative standard deviation from the mean of each sampling size (n = 2(x), where x = 1-6) of randomly selected samples was defined as the UPRL for each sampling size. The estimated UPRLs, which were calculated on the basis of the regulatory sampling size recommended by the OECD Guidelines on Crop Field Trials (weights from 1 to 5 kg, and commodity unit numbers from 12 to 24), ranged from 2.1% for cypermethrin in sweet peppers to 14.6% for cypermethrin in cabbage samples. The percentages of commodity exceeding the maximum residue limits (MRLs) specified by the Japanese Food Sanitation Law may be predicted from the equation derived from this study, which was based on samples of various size ranges with mean residue levels below the MRL. The estimated UPRLs have confirmed that sufficient sampling weight and numbers are required for analysis and/or re-examination of subsamples to provide accurate values of pesticide residue levels for the enforcement of MRLs. The equation derived from the present study would aid the estimation of more accurate residue levels even from small sampling sizes. PMID:22475588
Hsu, Ya-Wen; Liou, Tsan-Hon; Liou, Yiing Mei; Chen, Hsin-Jen; Chien, Li-Yin
2016-01-01
Children and adolescents tend to lose weight, which may be associated with misperceptions of weight. Previous studies have emphasized establishing correlations between eating disorders and an overestimated perception of body weight, but few studies have focused on an underestimated perception of body weight. The objective of this study was to explore the relationship between misperceptions of body weight and weight-related risk factors, such as eating disorders, inactivity, and unhealthy behaviors, among overweight children who underestimated their body weight. We conducted a cross-sectional, descriptive study between December 1, 2006 and February 15, 2007. A total of 29,313 children and adolescents studying in grades 4-12 were enrolled in this nationwide, cross-sectional survey, and they were asked to complete questionnaires. A multivariate logistic regression using maximum likelihood estimates was used. The prevalence of body weight misperception was 43.2% (26.4% overestimation and 16.8% underestimation). Factors associated with the underestimated perception of weight among overweight children were parental obesity, dietary control for weight loss, breakfast consumption, self-induced vomiting as a weight control strategy, fried food consumption, engaging in vigorous physical activities, and sleeping for >8 hours per day (odds ratios=0.86, 0.42, 0.88, 1.37, 1.13, 1.11, and 1.17, respectively). In conclusion, the early establishment of an accurate perception of body weight may mitigate unhealthy behaviors. PMID:26965769
Carels, Robert A; Konrad, Krista; Harper, Jessica
2007-09-01
People frequently place foods into "health" or "diet" categories. This study examined whether (1) evaluations of "healthiness/unhealthiness" influence "caloric" estimation accuracy, (2) people evaluate foods for "healthiness/unhealthiness" or "weight gain/loss" differently, and (3) food evaluations differ by gender, diet status, and weight. Also, undergraduate dieters attempting to lose weight on their own were compared to obese weight loss program participants. Undergraduate students (N=101) rated eight "healthy" and "unhealthy" foods on perceived "healthiness/unhealthiness," "weight loss/gain capacity" and "caloric" content. Open-ended questions inquiring why a food was "healthy/unhealthy" or would "contribute to weight gain/loss" were coded into independent food categories (e.g., high fat). Results indicate that calories were systematically underestimated in healthy/weight loss foods, while they were systematically overestimated in unhealthy/weight gain foods. Dieters were more accurate at estimating "calories" of healthy foods and more attentive to the foods' fat, "calorie", and sugar content than non-dieters. Overweight participants commented more on fat and sugar content than normal weight participants. Undergraduate dieters used fewer categories for evaluating foods than weight loss program participants. Individual difference characteristics, such as diet-status, weight, and gender, influence people's perceptions of foods' healthiness or capacity to influence weight, and in some instances systematically bias their estimates of the caloric content of foods. PMID:17428574
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Weight limits. 29.25 Section 29.25... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight General § 29.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Weight limits. 27.25 Section 27.25... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight General § 27.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part is...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Weight limits. 29.25 Section 29.25... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight General § 29.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight limits. 29.25 Section 29.25... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight General § 29.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Weight limits. 29.25 Section 29.25... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight General § 29.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Weight limits. 27.25 Section 27.25... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight General § 27.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part is...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Weight limits. 27.25 Section 27.25... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight General § 27.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part is...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight limits. 27.25 Section 27.25... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight General § 27.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part is...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Weight limits. 27.25 Section 27.25... STANDARDS: NORMAL CATEGORY ROTORCRAFT Flight General § 27.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part is...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Weight limits. 29.25 Section 29.25... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Flight General § 29.25 Weight limits. (a) Maximum weight. The maximum weight (the highest weight at which compliance with each applicable requirement of this part...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight limits. 31.14 Section 31.14... STANDARDS: MANNED FREE BALLOONS Flight Requirements § 31.14 Weight limits. (a) The range of weights over which the balloon may be safely operated must be established. (b) Maximum weight. The maximum weight...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Weight limits. 23.25 Section 23.25... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight General § 23.25 Weight limits. (a) Maximum weight. The maximum weight is the highest weight at which compliance with each...
7 CFR 51.1863 - Standard weight.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Standard weight. 51.1863 Section 51.1863 Agriculture... Standards for Fresh Tomatoes 1 Standard Weight § 51.1863 Standard weight. (a) When packages are marked to a net weight of 15 pounds (6.80 kg) or more, the net weight of the contents shall not be less than...
7 CFR 51.1863 - Standard weight.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 2 2011-01-01 2011-01-01 false Standard weight. 51.1863 Section 51.1863 Agriculture... Standards for Fresh Tomatoes 1 Standard Weight § 51.1863 Standard weight. (a) When packages are marked to a net weight of 15 pounds (6.80 kg) or more, the net weight of the contents shall not be less than...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight limits. 23.25 Section 23.25... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Flight General § 23.25 Weight limits. (a) Maximum weight. The maximum weight is the highest weight at which compliance with each...
The Cognitive Behavioral Approach to Weight Maintenance.
ERIC Educational Resources Information Center
Girdano, Dorothy Dusek
The cognitive behavioral approach to weight maintenance assumes that obese people should be concerned with weight control rather than weight loss, and it embraces both the behavioral approach and a maintenance program which examines risks, value priorities, and the basic principles of weight loss/weight gain. The University of Maryland offers a…
NASA Astrophysics Data System (ADS)
Afonina, I. A.; Kleptsyna, E. S.; Petukhov, V. L.; Patrashkov, S. A.
2003-05-01
Copper plays an important part in living being bodies. But, both high and low Cu levels may cause human and animal diseases. Some East Siberia areas are characterized by Cu pollution [1]. 5 group of hens were formed: 1 - control, 2-5 - experimental. For a month the hens from experimental groups were drunk with water where Cu content was 5, 10, 20 and 30 times higher than the upper limits (UL). Group 1 - 3 hens' weight was almost the same during the experiment. Weight decrease (from 2020 to 1656 g) was detected in group 4 (20 UL) for the first half a month. All the hens of group 4 except for 3 hens were died for the last 2 weeks. In group 5 (30 UL) all the hens died after 2 ... 14 days. Thus, high Cu concentrations (20 ... 30 UL) cause hens' weight reduction of and their death.
Accurate Alignment of Plasma Channels Based on Laser Centroid Oscillations
Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Osterhoff, Jens; Shiraishi, Satomi; Schroeder, Carl; Geddes, Cameron; Toth, Csaba; Esarey, Eric; Leemans, Wim
2011-03-23
A technique has been developed to accurately align a laser beam through a plasma channel by minimizing the shift in laser centroid and angle at the channel outptut. If only the shift in centroid or angle is measured, then accurate alignment is provided by minimizing laser centroid motion at the channel exit as the channel properties are scanned. The improvement in alignment accuracy provided by this technique is important for minimizing electron beam pointing errors in laser plasma accelerators.
Accurate wavelength calibration method for flat-field grating spectrometers.
Du, Xuewei; Li, Chaoyang; Xu, Zhe; Wang, Qiuping
2011-09-01
A portable spectrometer prototype is built to study wavelength calibration for flat-field grating spectrometers. An accurate calibration method called parameter fitting is presented. Both optical and structural parameters of the spectrometer are included in the wavelength calibration model, which accurately describes the relationship between wavelength and pixel position. Along with higher calibration accuracy, the proposed calibration method can provide information about errors in the installation of the optical components, which will be helpful for spectrometer alignment. PMID:21929865
Hwang, Beomsoo; Jeon, Doyoung
2015-01-01
In exoskeletal robots, the quantification of the user's muscular effort is important to recognize the user's motion intentions and evaluate motor abilities. In this paper, we attempt to estimate users' muscular efforts accurately using joint torque sensor which contains the measurements of dynamic effect of human body such as the inertial, Coriolis, and gravitational torques as well as torque by active muscular effort. It is important to extract the dynamic effects of the user's limb accurately from the measured torque. The user's limb dynamics are formulated and a convenient method of identifying user-specific parameters is suggested for estimating the user's muscular torque in robotic exoskeletons. Experiments were carried out on a wheelchair-integrated lower limb exoskeleton, EXOwheel, which was equipped with torque sensors in the hip and knee joints. The proposed methods were evaluated by 10 healthy participants during body weight-supported gait training. The experimental results show that the torque sensors are to estimate the muscular torque accurately in cases of relaxed and activated muscle conditions. PMID:25860074
Weight Loss Might Reduce Cancer Risk
... evidence in the jigsaw of the benefits of losing weight, and how important weight loss is to ... Hutchinson Cancer Research Center in Seattle. In general, losing weight reduces the risk of breast, colon and ...
Supporting your child with weight loss
... health care provider can set healthy goals for weight-loss and help with monitoring and support. Getting support ... to get the whole family to join a weight-loss plan, even if weight loss is not the ...
FDA Approves New Weight-Loss Device
... gov/news/fullstory_159362.html FDA Approves New Weight-Loss Device Surgically implanted port allows obese patients to ... have been unable to lose weight and maintain weight loss using nonsurgical treatments. The FDA approval is for ...
Weighted Means through the Looking Glass
ERIC Educational Resources Information Center
Falk, Ruma; Lann, Avital Lavie
2013-01-01
Each weighted mean of two values has a counterpart, equidistant from the arithmetic mean, obtained by exchanging roles between the weights or by inversing each weight. These elementary relations are apt for introductory courses.
Healthy Weight: You Can Do It, Too
... Issues Healthy Weight Healthy Weight: You Can Do It, Too Past Issues / Summer 2009 Table of Contents ... with NIH MedlinePlus magazine about how he did it, and what he does to maintain his weight. ...
Prediction of shelled shrimp weight by machine vision.
Pan, Peng-min; Li, Jian-ping; Lv, Gu-lai; Yang, Hui; Zhu, Song-ming; Lou, Jian-zhong
2009-08-01
The weight of shelled shrimp is an important parameter for grading process. The weight prediction of shelled shrimp by contour area is not accurate enough because of the ignorance of the shrimp thickness. In this paper, a multivariate prediction model containing area, perimeter, length, and width was established. A new calibration algorithm for extracting length of shelled shrimp was proposed, which contains binary image thinning, branch recognition and elimination, and length reconstruction, while its width was calculated during the process of length extracting. The model was further validated with another set of images from 30 shelled shrimps. For a comparison purpose, artificial neural network (ANN) was used for the shrimp weight predication. The ANN model resulted in a better prediction accuracy (with the average relative error at 2.67%), but took a tenfold increase in calculation time compared with the weight-area-perimeter (WAP) model (with the average relative error at 3.02%). We thus conclude that the WAP model is a better method for the prediction of the weight of shelled red shrimp. PMID:19650197
Prediction of shelled shrimp weight by machine vision
Pan, Peng-min; Li, Jian-ping; Lv, Gu-lai; Yang, Hui; Zhu, Song-ming; Lou, Jian-zhong
2009-01-01
The weight of shelled shrimp is an important parameter for grading process. The weight prediction of shelled shrimp by contour area is not accurate enough because of the ignorance of the shrimp thickness. In this paper, a multivariate prediction model containing area, perimeter, length, and width was established. A new calibration algorithm for extracting length of shelled shrimp was proposed, which contains binary image thinning, branch recognition and elimination, and length reconstruction, while its width was calculated during the process of length extracting. The model was further validated with another set of images from 30 shelled shrimps. For a comparison purpose, artificial neural network (ANN) was used for the shrimp weight predication. The ANN model resulted in a better prediction accuracy (with the average relative error at 2.67%), but took a tenfold increase in calculation time compared with the weight-area-perimeter (WAP) model (with the average relative error at 3.02%). We thus conclude that the WAP model is a better method for the prediction of the weight of shelled red shrimp. PMID:19650197
Robust fusion with reliabilities weights
NASA Astrophysics Data System (ADS)
Grandin, Jean-Francois; Marques, Miguel
2002-03-01
The reliability is a value of the degree of trust in a given measurement. We analyze and compare: ML (Classical Maximum Likelihood), MLE (Maximum Likelihood weighted by Entropy), MLR (Maximum Likelihood weighted by Reliability), MLRE (Maximum Likelihood weighted by Reliability and Entropy), DS (Credibility Plausibility), DSR (DS weighted by reliabilities). The analysis is based on a model of a dynamical fusion process. It is composed of three sensors, which have each it's own discriminatory capacity, reliability rate, unknown bias and measurement noise. The knowledge of uncertainties is also severely corrupted, in order to analyze the robustness of the different fusion operators. Two sensor models are used: the first type of sensor is able to estimate the probability of each elementary hypothesis (probabilistic masses), the second type of sensor delivers masses on union of elementary hypotheses (DS masses). In the second case probabilistic reasoning leads to sharing the mass abusively between elementary hypotheses. Compared to the classical ML or DS which achieves just 50% of correct classification in some experiments, DSR, MLE, MLR and MLRE reveals very good performances on all experiments (more than 80% of correct classification rate). The experiment was performed with large variations of the reliability coefficients for each sensor (from 0 to 1), and with large variations on the knowledge of these coefficients (from 0 0.8). All four operators reveal good robustness, but the MLR reveals to be uniformly dominant on all the experiments in the Bayesian case and achieves the best mean performance under incomplete a priori information.
Dietary Supplements for Weight Loss
... supplements, they won’t be listed on the product label and they could harm you. Weight-loss supplements can be sold without being tested or approved by the U.S. Food and Drug ... can recall that product. Visit this website to view the FDA’s public ...
Generating Constant Weight Binary Codes
ERIC Educational Resources Information Center
Knight, D.G.
2008-01-01
The determination of bounds for A(n, d, w), the maximum possible number of binary vectors of length n, weight w, and pairwise Hamming distance no less than d, is a classic problem in coding theory. Such sets of vectors have many applications. A description is given of how the problem can be used in a first-year undergraduate computational…
Psychosocial Consequences of Weight Cycling.
ERIC Educational Resources Information Center
Bartlett, Susan J.; And Others
1996-01-01
Participants were 130 obese women who reported undertaking a mean lifetime total of 4.7 major diets on which they had lost a mean of 45.9 kilograms. Participants with a severe history of weight cycling had a significantly younger age of onset of obesity than mild cyclers and reported initiating dieting at a significantly younger age and lower…
ERIC Educational Resources Information Center
Jacobsen, Tim; Jenkins, Jayne
2006-01-01
Physical educators continually investigate purposeful, meaningful, and authentic means to assess student learning in relationship to the national standards. Here, the authors describe a means of assessing several of the national standards for physical education in a high school weight training class. Adopting the North Dakota Standards for…
ALCOHOL CONSUMPTION AND BODY WEIGHT
FRENCH, MICHAEL T.; NORTON, EDWARD C.; FANG, HAI; MACLEAN, JOHANNA CATHERINE
2011-01-01
SUMMARY The number of Americans who are overweight or obese has reached epidemic proportions. Elevated weight is associated with health problems and increased medical expenditures. This paper analyzes Waves 1 and 2 of the National Epidemiological Survey of Alcohol and Related Conditions (NESARC) to investigate the role of alcohol consumption in weight gain. Alcohol is not only an addictive substance but also a high-calorie beverage that can interfere with metabolic function and cognitive processes. Because men and women differ in the type and amount of alcohol they consume, in the biological effects they experience as a result of alcohol consumption, and in the consequences they face as a result of obesity, we expect our results to differ by gender. We use first-difference models of body mass index (BMI) and alcohol consumption (frequency and intensity) to control for time-invariant unobservable factors that may influence changes in both alcohol use and weight status. Increasing frequency and intensity of alcohol use is associated with statistically significant yet quantitatively small weight gain for men but not for women. Moreover, the first-difference results are much smaller in magnitude and sometimes different in sign compared to the benchmark pooled cross-sectional estimates. PMID:19548203
ERIC Educational Resources Information Center
Lenhart, Clare M.; Daly, Brian P.; Eichen, Dawn M.
2011-01-01
Current evidence is equivocal as to whether adolescent's perception of weight status is linked to both healthy and risky behaviors. This study examined the association between accurate and inaccurate perception of weight and self-reported health and risk behaviors among a diverse sample of obese, urban adolescents. Data were analyzed from 1,180…
Lemon, Stephenie C.; Pagoto, Sherry L.; Barton, Bruce A.; Lapane, Kate L.; Goldberg, Robert J.
2014-01-01
Introduction The objective of our study was to describe perceptions of child weight status among US children, adolescents, and their parents and to examine the extent to which accurate personal and parental perception of weight status is associated with self-reported attempted weight loss. Methods Our study sample comprised 2,613 participants aged 8 to 15 years in the National Health and Nutrition Examination Survey from the 2 most recent consecutive cycles (2007–2008 and 2009–2010). Categories of weight perception were developed by comparing measured to perceived weight status. Multivariable logistic regression analyses were used to examine the association between weight misperception and self-reported attempted weight loss. Results Among children and adolescents, 27.3% underestimated and 2.8% overestimated their weight status. Among parents, 25.2% underestimated and 1.1% overestimated their child’s weight status. Logistic regression analyses showed that the odds of self-reported attempted weight loss was 9.5 times as high (95% confidence interval [CI]: 3.8–23.6) among healthy-weight children and adolescents who overestimated their weight status as among those who perceived their weight status accurately; the odds of self-reported attempted weight loss were 3.9 (95% CI, 2.4–6.4) and 2.9 (95% CI, 1.8–4.6) times as high among overweight and obese children and adolescents, respectively, who accurately perceived their weight status than among those who underestimated their weight status. Parental misperception of weight was not significantly associated with self-reported attempted weight loss among children and adolescents who were overweight or obese. Conclusion Efforts to prevent childhood obesity should incorporate education for both children and parents regarding the proper identification and interpretation of actual weight status. Interventions for appropriate weight loss can target children directly because one of the major driving forces to lose
Mir, N; Sohaib, S A; Collins, D; Koh, D M
2010-08-01
Accurate identification of lymph nodes facilitates nodal assessment by size, morphological or MR lymphographic criteria. We compared the MR detection of lymph nodes in patients with pelvic cancers using T2-weighted imaging, and fusion of diffusion-weighted imaging (DWI) and T2-weighted imaging. Twenty patients with pelvic tumours underwent 5-mm axial T2-weighted and DWI (b-values 0-750 s/mm(2)) on a 1.5T system. Fusion images of b = 750 s/mm(2) diffusion-weighted MR and T2-weighted images were created. Two radiologists evaluated in consensus the T2-weighted images and fusion images independently. For each image set, the location and diameter of pelvic nodes were recorded, and nodal visibility was scored using a 4-point scale (0-3). Nodal visualisation was compared using Relative to an Identified Distribution (RIDIT) analysis. The mean RIDIT score describes the probability that a randomly selected node will be better visualised relative to the other image set. One hundred fourteen pelvic nodes (mean 5.9 mm; 2-10 mm) were identified on T2-weighted images and 161 nodes (mean 4.3 mm; 2-10 mm) on fusion images. Using fusion images, 47 additional nodes were detected compared with T2-weighted images alone (eight external iliac, 24 inguinal, 12 obturator, two peri-rectal, one presacral). Nodes detected only on fusion images were 2-9 mm (mean 3.7 mm). Nodal visualisation was better using fusion images compared with T2-weighted images (mean RIDIT score 0.689 vs 0.302). Fusion of diffusion-weighted MR with T2-weighted images improves identification of pelvic lymph nodes compared with T2-weighted images alone. The improved nodal identification may aid treatment planning and further nodal characterisation. PMID:20718916
Cerebral microbleed segmentation from susceptibility weighted images
NASA Astrophysics Data System (ADS)
Roy, Snehashis; Jog, Amod; Magrath, Elizabeth; Butman, John A.; Pham, Dzung L.
2015-03-01
Cerebral microbleeds (CMB) are a common marker of traumatic brain injury. Accurate detection and quantification of the CMBs are important for better understanding the progression and prognosis of the injury. Previous microbleed detection methods have suffered from a high rate of false positives, which is time consuming to manually correct. In this paper, we propose a fully automatic, example-based method to segment CMBs from susceptibility-weighted (SWI) scans, where examples from an already segmented template SWI image are used to detect CMBs in a new image. First, multiple radial symmetry transforms (RST) are performed on the template SWI to detect small ellipsoidal structures, which serve as potential microbleed candidates. Then 3D patches from the SWI and its RSTs are combined to form a feature vector at each voxel of the image. A random forest regression is trained using the feature vectors, where the dependent variable is the binary segmentation voxel of the template. Once the regression is learnt, it is applied to a new SWI scan, whose feature vectors contain patches from SWI and its RSTs. Experiments on 26 subjects with mild to severe brain injury show a CMB detection sensitivity of 85:7%, specificity 99:5%, and a false positive to true positive ratio of 1:73, which is competitive with published methods while providing a significant reduction in computation time.
Diffusion-weighted imaging of pancreatic cancer.
De Robertis, Riccardo; Tinazzi Martini, Paolo; Demozzi, Emanuele; Dal Corso, Flavia; Bassi, Claudio; Pederzoli, Paolo; D'Onofrio, Mirko
2015-10-28
Magnetic resonance imaging (MRI) is a reliable and accurate imaging method for the evaluation of patients with pancreatic ductal adenocarcinoma (PDAC). Diffusion-weighted imaging (DWI) is a relatively recent technological improvement that expanded MRI capabilities, having brought functional aspects into conventional morphologic MRI evaluation. DWI can depict the random diffusion of water molecules within tissues (the so-called Brownian motions). Modifications of water diffusion induced by different factors acting on the extracellular and intracellular spaces, as increased cell density, edema, fibrosis, or altered functionality of cell membranes, can be detected using this MR sequence. The intravoxel incoherent motion (IVIM) model is an advanced DWI technique that consent a separate quantitative evaluation of all the microscopic random motions that contribute to DWI, which are essentially represented by molecular diffusion and blood microcirculation (perfusion). Technological improvements have made possible the routine use of DWI during abdominal MRI study. Several authors have reported that the addition of DWI sequence can be of value for the evaluation of patients with PDAC, especially improving the staging; nevertheless, it is still unclear whether and how DWI could be helpful for identification, characterization, prognostic stratification and follow-up during treatment. The aim of this paper is to review up-to-date literature data regarding the applications of DWI and IVIM to PDACs. PMID:26516428
Diffusion-weighted imaging of pancreatic cancer
De Robertis, Riccardo; Tinazzi Martini, Paolo; Demozzi, Emanuele; Dal Corso, Flavia; Bassi, Claudio; Pederzoli, Paolo; D’Onofrio, Mirko
2015-01-01
Magnetic resonance imaging (MRI) is a reliable and accurate imaging method for the evaluation of patients with pancreatic ductal adenocarcinoma (PDAC). Diffusion-weighted imaging (DWI) is a relatively recent technological improvement that expanded MRI capabilities, having brought functional aspects into conventional morphologic MRI evaluation. DWI can depict the random diffusion of water molecules within tissues (the so-called Brownian motions). Modifications of water diffusion induced by different factors acting on the extracellular and intracellular spaces, as increased cell density, edema, fibrosis, or altered functionality of cell membranes, can be detected using this MR sequence. The intravoxel incoherent motion (IVIM) model is an advanced DWI technique that consent a separate quantitative evaluation of all the microscopic random motions that contribute to DWI, which are essentially represented by molecular diffusion and blood microcirculation (perfusion). Technological improvements have made possible the routine use of DWI during abdominal MRI study. Several authors have reported that the addition of DWI sequence can be of value for the evaluation of patients with PDAC, especially improving the staging; nevertheless, it is still unclear whether and how DWI could be helpful for identification, characterization, prognostic stratification and follow-up during treatment. The aim of this paper is to review up-to-date literature data regarding the applications of DWI and IVIM to PDACs. PMID:26516428
Nonexposure accurate location K-anonymity algorithm in LBS.
Jia, Jinying; Zhang, Fengli
2014-01-01
This paper tackles location privacy protection in current location-based services (LBS) where mobile users have to report their exact location information to an LBS provider in order to obtain their desired services. Location cloaking has been proposed and well studied to protect user privacy. It blurs the user's accurate coordinate and replaces it with a well-shaped cloaked region. However, to obtain such an anonymous spatial region (ASR), nearly all existent cloaking algorithms require knowing the accurate locations of all users. Therefore, location cloaking without exposing the user's accurate location to any party is urgently needed. In this paper, we present such two nonexposure accurate location cloaking algorithms. They are designed for K-anonymity, and cloaking is performed based on the identifications (IDs) of the grid areas which were reported by all the users, instead of directly on their accurate coordinates. Experimental results show that our algorithms are more secure than the existent cloaking algorithms, need not have all the users reporting their locations all the time, and can generate smaller ASR. PMID:24605060
Nonexposure Accurate Location K-Anonymity Algorithm in LBS
2014-01-01
This paper tackles location privacy protection in current location-based services (LBS) where mobile users have to report their exact location information to an LBS provider in order to obtain their desired services. Location cloaking has been proposed and well studied to protect user privacy. It blurs the user's accurate coordinate and replaces it with a well-shaped cloaked region. However, to obtain such an anonymous spatial region (ASR), nearly all existent cloaking algorithms require knowing the accurate locations of all users. Therefore, location cloaking without exposing the user's accurate location to any party is urgently needed. In this paper, we present such two nonexposure accurate location cloaking algorithms. They are designed for K-anonymity, and cloaking is performed based on the identifications (IDs) of the grid areas which were reported by all the users, instead of directly on their accurate coordinates. Experimental results show that our algorithms are more secure than the existent cloaking algorithms, need not have all the users reporting their locations all the time, and can generate smaller ASR. PMID:24605060
14 CFR 25.1519 - Weight, center of gravity, and weight distribution.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Weight, center of gravity, and weight... Information Operating Limitations § 25.1519 Weight, center of gravity, and weight distribution. The airplane weight, center of gravity, and weight distribution limitations determined under §§ 25.23 through...
14 CFR 25.1519 - Weight, center of gravity, and weight distribution.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Weight, center of gravity, and weight... Information Operating Limitations § 25.1519 Weight, center of gravity, and weight distribution. The airplane weight, center of gravity, and weight distribution limitations determined under §§ 25.23 through...
14 CFR 25.1519 - Weight, center of gravity, and weight distribution.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Weight, center of gravity, and weight... Information Operating Limitations § 25.1519 Weight, center of gravity, and weight distribution. The airplane weight, center of gravity, and weight distribution limitations determined under §§ 25.23 through...
14 CFR 25.1519 - Weight, center of gravity, and weight distribution.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight, center of gravity, and weight... Information Operating Limitations § 25.1519 Weight, center of gravity, and weight distribution. The airplane weight, center of gravity, and weight distribution limitations determined under §§ 25.23 through...
14 CFR 25.1519 - Weight, center of gravity, and weight distribution.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Weight, center of gravity, and weight... Information Operating Limitations § 25.1519 Weight, center of gravity, and weight distribution. The airplane weight, center of gravity, and weight distribution limitations determined under §§ 25.23 through...
Maternal nutrition and birth weight.
Martorell, R; Gonzalez-cossio, T
1987-01-01
Low birth weight (LBW) babies (2500 gm or less at birth) are more likely to die and suffer sequelae. Intrauterine growth retardation (IUGR) babies also weight the same, but they are born at 37 weeks or over. Small for gestational age (SGA) is a related term used for babies weighing less than expected. 20.6 million LBW babies were born in 1979, most of then in developing countries. In the US, 12.1% of nonwhites vs. 6% of whites had LBW babies in 1980 (50% of infant deaths were attributed to LBWs). A study in Guatemala showed that LBWs accounted for 88% of neonatal deaths. 15-21% of the US decline in neonatal mortality since the 1960s was due to birth weight distribution. 50% of the decline in Alabama was attributable to improved obstetrical care from 1970 to 1980. 12,000 Finnish children were followed up for 14 years, and those born with weights below the mean had significantly higher mortality than normal weight children. The saving of very LBW babies by medical technology has raised ethical questions, as many have mental and physical retardation and the expenses are enormous. SGAs have smaller stature IUGR/low ponderal index infants had 2.9-5.7 times the mortality of full-term normal infants, and they also had poorer academic progress, but IUGR/adequate ponderal index babies fared even worse. Such afflictions carry across generations, as evidenced by a Seattle study on 748 white women indicating impaired reproductive performance of female infants. Some of the components producing LBW are: maternal genetic, social, cultural, and nutritional factors, smoking, and dieting during pregnancy, wars and famines (e.g., Leningrad and Wuppertal during and after World War II). Anthropometric studies indicate that mothers with greater body size have larger babies, but genetics also play a role here. Intervention studies confirmed the importance of nutrition: in a Mexican study and increase of 180 gm of birth weight and 29.6% reduction of LBW was produced by supplementation
ERIC Educational Resources Information Center
Verstraelen, C. J. F.; Maaskant, M. A.; van Knijff-Raeven, A. G. M.; Curfs, L. M. G.; van Schrojenstein Lantman-de Valk, H. M. J.
2009-01-01
Background: The aims of this study were (1) to determine to what extent body mass index (BMI), waist circumference, fat free mass index (FFMI) and skinfold thickness are feasible measurement options in people with intellectual disabilities (ID) to measure their weight status, and (2) to assess the level of agreement among these methods. Methods:…
Accurate Fiber Length Measurement Using Time-of-Flight Technique
NASA Astrophysics Data System (ADS)
Terra, Osama; Hussein, Hatem
2016-06-01
Fiber artifacts of very well-measured length are required for the calibration of optical time domain reflectometers (OTDR). In this paper accurate length measurement of different fiber lengths using the time-of-flight technique is performed. A setup is proposed to measure accurately lengths from 1 to 40 km at 1,550 and 1,310 nm using high-speed electro-optic modulator and photodetector. This setup offers traceability to the SI unit of time, the second (and hence to meter by definition), by locking the time interval counter to the Global Positioning System (GPS)-disciplined quartz oscillator. Additionally, the length of a recirculating loop artifact is measured and compared with the measurement made for the same fiber by the National Physical Laboratory of United Kingdom (NPL). Finally, a method is proposed to relatively correct the fiber refractive index to allow accurate fiber length measurement.
Differential equation based method for accurate approximations in optimization
NASA Technical Reports Server (NTRS)
Pritchard, Jocelyn I.; Adelman, Howard M.
1990-01-01
A method to efficiently and accurately approximate the effect of design changes on structural response is described. The key to this method is to interpret sensitivity equations as differential equations that may be solved explicitly for closed form approximations, hence, the method is denoted the Differential Equation Based (DEB) method. Approximations were developed for vibration frequencies, mode shapes and static displacements. The DEB approximation method was applied to a cantilever beam and results compared with the commonly-used linear Taylor series approximations and exact solutions. The test calculations involved perturbing the height, width, cross-sectional area, tip mass, and bending inertia of the beam. The DEB method proved to be very accurate, and in most cases, was more accurate than the linear Taylor series approximation. The method is applicable to simultaneous perturbation of several design variables. Also, the approximations may be used to calculate other system response quantities. For example, the approximations for displacements are used to approximate bending stresses.
Respiratory weight losses during exercise.
NASA Technical Reports Server (NTRS)
Mitchell, J. W.; Nadel, E. R.; Stolwijk, J. A. J.
1972-01-01
Evaporative water loss from the respiratory tract was determined over a wide range of exercise. The absolute humidity of the expired air was the same at all levels of exercise and equal to that measured at rest. The rate of respiratory water loss during exercise was found to be 0.019 of the oxygen uptake times (44 minus water vapor pressure). The rate of weight loss during exercise due to CO2-O2 exchange was calculated. For exercise at oxygen consumption rates exceeding 1.5 L/min in a dry environment with a water vapor pressure of 10 mm Hg, the total rate of weight loss via the respiratory tract is on the order of 2-5 g/min.
Temporal weighting in sound localizationa
Stecker, G. Christopher; Hafter, Ervin R.
2010-01-01
The dynamics of sound localization were studied using a free-field direct localization task (pointing to sound sources) and an observer-weighting analysis that assessed the relative influence of each click in a click-train stimulus. In agreement with previous studies of the precedence effect and binaural adaptation, weighting functions showed increased influence of the onset click when the interclick interval (ICI) was short (<5 ms). For longer ICIs, all clicks in a train contributed roughly the same amount to listeners’ localization responses. Finally, when a short gap was introduced in the middle of a train, the influence of the click immediately following the gap increased, in agreement with the “restarting” results obtained by Hafter and Buell PMID:12243153
Multilayer weighted social network model
NASA Astrophysics Data System (ADS)
Murase, Yohsuke; Török, János; Jo, Hang-Hyun; Kaski, Kimmo; Kertész, János
2014-11-01
Recent empirical studies using large-scale data sets have validated the Granovetter hypothesis on the structure of the society in that there are strongly wired communities connected by weak ties. However, as interaction between individuals takes place in diverse contexts, these communities turn out to be overlapping. This implies that the society has a multilayered structure, where the layers represent the different contexts. To model this structure we begin with a single-layer weighted social network (WSN) model showing the Granovetterian structure. We find that when merging such WSN models, a sufficient amount of interlayer correlation is needed to maintain the relationship between topology and link weights, while these correlations destroy the enhancement in the community overlap due to multiple layers. To resolve this, we devise a geographic multilayer WSN model, where the indirect interlayer correlations due to the geographic constraints of individuals enhance the overlaps between the communities and, at the same time, the Granovetterian structure is preserved.
Sénéchal, Martin; Slaght, Jana; Bouchard, Danielle R.
2015-01-01
Objectives. To evaluate if cumulative weight exposure is associated with weight loss strategy choices and weight loss success. Methods. Data from the National Health and Nutrition Examination Survey were used; a total of 4,562 people age 50 years or older who reported trying to lose weight in the last year were studied. Cumulative weight exposure (CWE) score was defined as the sum of body mass index points above 25 kg/m2 at the age of 25, 10 years ago, 1 year ago, and now. Weight loss strategies were self-reported and weight loss success was defined as reaching a 5% weight loss in the last year. Results. Chosen strategies for weight loss vary across tertiles of CWE. Participants in the highest CWE tertile were about 4 to 20 times more likely to lose at least 5% of body weight in the past year compared to those in the lowest CWE tertile (P < 0.05). Discussion. Strategies used to lose weight and weight loss success using different weight loss strategies vary considerably across cumulative weight exposure. Thus, cumulative weight exposure might be a variable worth considering when intervening with this population. PMID:26161269
Elfhag, K; Rössner, S
2005-02-01
Weight loss is difficult to achieve and maintaining the weight loss is an even greater challenge. The identification of factors associated with weight loss maintenance can enhance our understanding for the behaviours and prerequisites that are crucial in sustaining a lowered body weight. In this paper we have reviewed the literature on factors associated with weight loss maintenance and weight regain. We have used a definition of weight maintenance implying intentional weight loss that has subsequently been maintained for at least 6 months. According to our review, successful weight maintenance is associated with more initial weight loss, reaching a self-determined goal weight, having a physically active lifestyle, a regular meal rhythm including breakfast and healthier eating, control of over-eating and self-monitoring of behaviours. Weight maintenance is further associated with an internal motivation to lose weight, social support, better coping strategies and ability to handle life stress, self-efficacy, autonomy, assuming responsibility in life, and overall more psychological strength and stability. Factors that may pose a risk for weight regain include a history of weight cycling, disinhibited eating, binge eating, more hunger, eating in response to negative emotions and stress, and more passive reactions to problems. PMID:15655039
Weight, gravitation, inertia, and tides
NASA Astrophysics Data System (ADS)
Pujol, Olivier; Lagoute, Christophe; Pérez, José-Philippe
2015-11-01
This paper deals with the factors that influence the weight of an object near the Earth's surface. They are: (1) the Earth's gravitational force, (2) the centrifugal force due to the Earth's diurnal rotation, and (3) tidal forces due to the gravitational field of the Moon and Sun, and other solar system bodies to a lesser extent. Each of these three contributions is discussed and expressions are derived. The relationship between weight and gravitation is thus established in a direct and pedagogical manner readily understandable by undergraduate students. The analysis applies to the Newtonian limit of gravitation. The derivation is based on an experimental (or operational) definition of weight, and it is shown that it coincides with the Earth’s gravitational force modified by diurnal rotation around a polar axis and non-uniformity of external gravitational bodies (tidal term). Two examples illustrate and quantify these modifications, respectively the Eötvös effect and the oceanic tides; tidal forces due to differential gravitation on a spacecraft and an asteroid are also proposed as examples. Considerations about inertia are also given and some comments are made about a widespread, yet confusing, explanation of tides based on a centrifugal force. Finally, the expression of the potential energy of the tide-generating force is established rigorously in the appendix.
Peroneal neuropathy after weight loss.
Cruz-Martinez, A; Arpa, J; Palau, F
2000-06-01
The objectives of this study were to evaluate the clinical and electrophysiological findings in peroneal mononeuropathies following a weight-reduction diet. Thirty patients with acute peroneal palsy and weight loss were studied. Complete nerve conduction studies (NCS) were performed in upper and lower limbs. NCS showed conduction block (CB) of the peroneal nerve at the fibular head that recovered in 29 patients within 3 weeks to 3 months. Severity of CB was correlated with clinical weakness. Three patients had abnormalities consistent with polyneuropathy (PNP). NCS in asymptomatic relatives confirmed familial neuropathy. Nerve biopsy and molecular study were consistent with hereditary neuropathy with liability to pressure palsies (HNPP). One of these peroneal palsies (6 months) recovered after neurolysis. Weight loss might be a risk factor in peroneal mononeuropathies. NCS is a tool in the diagnosis of the site and severity of the nerve injury. Testing should be considered for relatives of patients with PNP because peroneal mononeuropathies may be the first expression of HNPP. PMID:10905469
Accurate upwind-monotone (nonoscillatory) methods for conservation laws
NASA Technical Reports Server (NTRS)
Huynh, Hung T.
1992-01-01
The well known MUSCL scheme of Van Leer is constructed using a piecewise linear approximation. The MUSCL scheme is second order accurate at the smooth part of the solution except at extrema where the accuracy degenerates to first order due to the monotonicity constraint. To construct accurate schemes which are free from oscillations, the author introduces the concept of upwind monotonicity. Several classes of schemes, which are upwind monotone and of uniform second or third order accuracy are then presented. Results for advection with constant speed are shown. It is also shown that the new scheme compares favorably with state of the art methods.
Accurate stress resultants equations for laminated composite deep thick shells
Qatu, M.S.
1995-11-01
This paper derives accurate equations for the normal and shear force as well as bending and twisting moment resultants for laminated composite deep, thick shells. The stress resultant equations for laminated composite thick shells are shown to be different from those of plates. This is due to the fact the stresses over the thickness of the shell have to be integrated on a trapezoidal-like shell element to obtain the stress resultants. Numerical results are obtained and showed that accurate stress resultants are needed for laminated composite deep thick shells, especially if the curvature is not spherical.
Must Kohn-Sham oscillator strengths be accurate at threshold?
Yang Zenghui; Burke, Kieron; Faassen, Meta van
2009-09-21
The exact ground-state Kohn-Sham (KS) potential for the helium atom is known from accurate wave function calculations of the ground-state density. The threshold for photoabsorption from this potential matches the physical system exactly. By carefully studying its absorption spectrum, we show the answer to the title question is no. To address this problem in detail, we generate a highly accurate simple fit of a two-electron spectrum near the threshold, and apply the method to both the experimental spectrum and that of the exact ground-state Kohn-Sham potential.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Weight limits. 25.25 Section 25.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.25 Weight limits. (a) Maximum weights. Maximum weights corresponding to the...
Weight Training for Strength and Power.
ERIC Educational Resources Information Center
President's Council on Physical Fitness and Sports, Washington, DC.
This paper begins by defining the terms "weight training,""weight lifting,""strength,""power," and "muscular endurance.""Weight training" is differentiated from "weight lifting" and defined as a systematic series of resistance exercises designed to promote physical development and conditioning or to rehabilitate persons who have suffered injury or…
Parents: Stay Mum on Daughter's Weight
... parents commented on their weight when they were girls were less satisfied with their weight as adults. This suggests that weight-related comments from parents caused harm to the women's body image, regardless of their current weight, the researchers said. ...
Weight Status of Persons with Intellectual Disabilities
ERIC Educational Resources Information Center
Maaskant, Marian A.; van Knijff-Raeven, Ankie G. M.; van Schrojenstein Lantman-de Valk, Henny M. J.; Veenstra, Marja Y.
2009-01-01
Background: The aim was to study the weight and weight status of the study group in 2002 and 2007, and to study the differences in weight and weight status between 2002 and 2007 and the risk groups for (becoming) overweight/obese. Materials and Methods: The Body Mass Index (BMI) of 336 clients of a Dutch service provider for persons with…
7 CFR 983.6 - Assessed weight.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Assessed weight. 983.6 Section 983.6 Agriculture..., ARIZONA, AND NEW MEXICO Definitions § 983.6 Assessed weight. Assessed weight means pounds of inshell pistachios, with the weight computed at 5 percent moisture, received for processing by a handler within...
7 CFR 983.6 - Assessed weight.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Assessed weight. 983.6 Section 983.6 Agriculture..., ARIZONA, AND NEW MEXICO Definitions § 983.6 Assessed weight. Assessed weight means pounds of inshell pistachios, with the weight computed at 5 percent moisture, received for processing by a handler within...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Kernel weight. 981.9 Section 981.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 981.9 Kernel weight. Kernel weight means the weight of kernels,...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Kernel weight. 981.9 Section 981.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 981.9 Kernel weight. Kernel weight means the weight of kernels,...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Weight limits. 25.25 Section 25.25... STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.25 Weight limits. (a) Maximum weights. Maximum weights corresponding to the airplane operating conditions (such as ramp, ground or water taxi,...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Weight limits. 25.25 Section 25.25... STANDARDS: TRANSPORT CATEGORY AIRPLANES Flight General § 25.25 Weight limits. (a) Maximum weights. Maximum weights corresponding to the airplane operating conditions (such as ramp, ground or water taxi,...
Obesity Prevention and Weight Maintenance After Loss.
German, Alexander James
2016-09-01
Obesity is one of the most prevalent medical diseases in pets. Outcomes are often disappointing; many animals either fail to reach target weight or regain weight. This article discusses managing obesity, focusing on prevention. It gives guidance on establishing monitoring programs that use regular body weight and condition assessments to identify animals at risk of inappropriate weight gain, enabling early intervention. Weight management in obese animals is a lifelong process. Regular weight and body condition monitoring are key to identifying animals that rebound early, while continuing to feed a therapeutic weight loss diet can help prevent it from happening. PMID:27255281
Random Weighted Sobolev Inequalities and Application to Quantum Ergodicity
NASA Astrophysics Data System (ADS)
Robert, Didier; Thomann, Laurent
2015-05-01
This paper is a continuation of Poiret et al. (Ann Henri Poincaré 16:651-689, 2015), where we studied a randomisation method based on the Laplacian with harmonic potential. Here we extend our previous results to the case of any polynomial and confining potential V on . We construct measures, under concentration type assumptions, on the support of which we prove optimal weighted Sobolev estimates on . This construction relies on accurate estimates on the spectral function in a non-compact configuration space. Then we prove random quantum ergodicity results without specific assumption on the classical dynamics. Finally, we prove that almost all bases of Hermite functions are quantum uniquely ergodic.
Williams, L. A.; Evans, S. F.; Newnham, J. P.
1997-01-01
OBJECTIVES: To determine the demographic, environmental, and medical factors that influence the relative weights of the newborn infant and the placenta and compare this ratio with other factors known to predispose to adult ill health. DESIGN: Prospective cohort study. SETTING: The tertiary referral centre for perinatal care in Perth, Western Australia. SUBJECTS: 2507 pregnant women who delivered a single live infant at term. MAIN OUTCOME MEASURES: Placental weight, birth weight, and the ratio of placental weight to birth weight. RESULTS: By multiple regression analysis the placental weight to birthweight ratio was significantly and positively associated with gestational age, female sex, Asian parentage, increasing maternal body mass index, increased maternal weight at booking, lower socioeconomic status, maternal anaemia, and increasing number of cigarettes smoked daily. There were no consistent relations between the placental weight to birthweight ratio and measures of newborn size. CONCLUSIONS: The ratio of placental weight to birth weight is not an accurate marker of fetal growth. In its role as a predictor of adult disease the ratio may be acting as a surrogate for other factors which are already known to influence health and may act before or after birth. Determining the role that relative growth rates of the fetus and placenta have in predisposing to adult disease requires prospective study to account for the many confounding variables which complicate this hypothesis. PMID:9224128
Monitoring circuit accurately measures movement of solenoid valve
NASA Technical Reports Server (NTRS)
Gillett, J. D.
1966-01-01
Solenoid operated valve in a control system powered by direct current issued to accurately measure the valve travel. This system is currently in operation with a 28-vdc power system used for control of fluids in liquid rocket motor test facilities.
A Self-Instructional Device for Conditioning Accurate Prosody.
ERIC Educational Resources Information Center
Buiten, Roger; Lane, Harlan
1965-01-01
A self-instructional device for conditioning accurate prosody in second-language learning is described in this article. The Speech Auto-Instructional Device (SAID) is electro-mechanical and performs three functions: SAID (1) presents to the student tape-recorded pattern sentences that are considered standards in prosodic performance; (2) processes…
Second-order accurate nonoscillatory schemes for scalar conservation laws
NASA Technical Reports Server (NTRS)
Huynh, Hung T.
1989-01-01
Explicit finite difference schemes for the computation of weak solutions of nonlinear scalar conservation laws is presented and analyzed. These schemes are uniformly second-order accurate and nonoscillatory in the sense that the number of extrema of the discrete solution is not increasing in time.
Bioaccessibility tests accurately estimate bioavailability of lead to quail
Technology Transfer Automated Retrieval System (TEKTRAN)
Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb, we incorporated Pb-contaminated soils or Pb acetate into diets for Japanese quail (Coturnix japonica), fed the quail for 15 days, and ...
Accurately Detecting Students' Lies regarding Relational Aggression by Correctional Instructions
ERIC Educational Resources Information Center
Dickhauser, Oliver; Reinhard, Marc-Andre; Marksteiner, Tamara
2012-01-01
This study investigates the effect of correctional instructions when detecting lies about relational aggression. Based on models from the field of social psychology, we predict that correctional instruction will lead to a less pronounced lie bias and to more accurate lie detection. Seventy-five teachers received videotapes of students' true denial…
Accurate Measurements of the Local Deuterium Abundance from HST Spectra
NASA Technical Reports Server (NTRS)
Linsky, Jeffrey L.
1996-01-01
An accurate measurement of the primordial value of D/H would provide a critical test of nucleosynthesis models for the early universe and the baryon density. I briefly summarize the ongoing HST observations of the interstellar H and D Lyman-alpha absorption for lines of sight to nearby stars and comment on recent reports of extragalactic D/H measurements.
Quantifying Accurate Calorie Estimation Using the "Think Aloud" Method
ERIC Educational Resources Information Center
Holmstrup, Michael E.; Stearns-Bruening, Kay; Rozelle, Jeffrey
2013-01-01
Objective: Clients often have limited time in a nutrition education setting. An improved understanding of the strategies used to accurately estimate calories may help to identify areas of focused instruction to improve nutrition knowledge. Methods: A "Think Aloud" exercise was recorded during the estimation of calories in a standard dinner meal…
Benchmarking accurate spectral phase retrieval of single attosecond pulses
NASA Astrophysics Data System (ADS)
Wei, Hui; Le, Anh-Thu; Morishita, Toru; Yu, Chao; Lin, C. D.
2015-02-01
A single extreme-ultraviolet (XUV) attosecond pulse or pulse train in the time domain is fully characterized if its spectral amplitude and phase are both determined. The spectral amplitude can be easily obtained from photoionization of simple atoms where accurate photoionization cross sections have been measured from, e.g., synchrotron radiations. To determine the spectral phase, at present the standard method is to carry out XUV photoionization in the presence of a dressing infrared (IR) laser. In this work, we examine the accuracy of current phase retrieval methods (PROOF and iPROOF) where the dressing IR is relatively weak such that photoelectron spectra can be accurately calculated by second-order perturbation theory. We suggest a modified method named swPROOF (scattering wave phase retrieval by omega oscillation filtering) which utilizes accurate one-photon and two-photon dipole transition matrix elements and removes the approximations made in PROOF and iPROOF. We show that the swPROOF method can in general retrieve accurate spectral phase compared to other simpler models that have been suggested. We benchmark the accuracy of these phase retrieval methods through simulating the spectrogram by solving the time-dependent Schrödinger equation numerically using several known single attosecond pulses with a fixed spectral amplitude but different spectral phases.
BIOACCESSIBILITY TESTS ACCURATELY ESTIMATE BIOAVAILABILITY OF LEAD TO QUAIL
Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contami...
Device accurately measures and records low gas-flow rates
NASA Technical Reports Server (NTRS)
Branum, L. W.
1966-01-01
Free-floating piston in a vertical column accurately measures and records low gas-flow rates. The system may be calibrated, using an adjustable flow-rate gas supply, a low pressure gage, and a sequence recorder. From the calibration rates, a nomograph may be made for easy reduction. Temperature correction may be added for further accuracy.
A Simple and Accurate Method for Measuring Enzyme Activity.
ERIC Educational Resources Information Center
Yip, Din-Yan
1997-01-01
Presents methods commonly used for investigating enzyme activity using catalase and presents a new method for measuring catalase activity that is more reliable and accurate. Provides results that are readily reproduced and quantified. Can also be used for investigations of enzyme properties such as the effects of temperature, pH, inhibitors,…
Is a Writing Sample Necessary for "Accurate Placement"?
ERIC Educational Resources Information Center
Sullivan, Patrick; Nielsen, David
2009-01-01
The scholarship about assessment for placement is extensive and notoriously ambiguous. Foremost among the questions that continue to be unresolved in this scholarship is this one: Is a writing sample necessary for "accurate placement"? Using a robust data sample of student assessment essays and ACCUPLACER test scores, we put this question to the…
Efficient and accurate sound propagation using adaptive rectangular decomposition.
Raghuvanshi, Nikunj; Narain, Rahul; Lin, Ming C
2009-01-01
Accurate sound rendering can add significant realism to complement visual display in interactive applications, as well as facilitate acoustic predictions for many engineering applications, like accurate acoustic analysis for architectural design. Numerical simulation can provide this realism most naturally by modeling the underlying physics of wave propagation. However, wave simulation has traditionally posed a tough computational challenge. In this paper, we present a technique which relies on an adaptive rectangular decomposition of 3D scenes to enable efficient and accurate simulation of sound propagation in complex virtual environments. It exploits the known analytical solution of the Wave Equation in rectangular domains, and utilizes an efficient implementation of the Discrete Cosine Transform on Graphics Processors (GPU) to achieve at least a 100-fold performance gain compared to a standard Finite-Difference Time-Domain (FDTD) implementation with comparable accuracy, while also being 10-fold more memory efficient. Consequently, we are able to perform accurate numerical acoustic simulation on large, complex scenes in the kilohertz range. To the best of our knowledge, it was not previously possible to perform such simulations on a desktop computer. Our work thus enables acoustic analysis on large scenes and auditory display for complex virtual environments on commodity hardware. PMID:19590105
Accurate momentum transfer cross section for the attractive Yukawa potential
Khrapak, S. A.
2014-04-15
Accurate expression for the momentum transfer cross section for the attractive Yukawa potential is proposed. This simple analytic expression agrees with the numerical results better than to within ±2% in the regime relevant for ion-particle collisions in complex (dusty) plasmas.
Instrument accurately measures small temperature changes on test surface
NASA Technical Reports Server (NTRS)
Harvey, W. D.; Miller, H. B.
1966-01-01
Calorimeter apparatus accurately measures very small temperature rises on a test surface subjected to aerodynamic heating. A continuous thin sheet of a sensing material is attached to a base support plate through which a series of holes of known diameter have been drilled for attaching thermocouples to the material.
Uniform positive-weight quadratures for discrete ordinate transport calculations
Carew, J.F.; Zamonsky, G.
1999-02-01
Mechanical quadratures that allow systematic improvement and solution convergence are derived for application of the discrete ordinates method to the Boltzmann transport equation. the quadrature directions are arranged on n latitudinal levels, are uniformly distributed over the unit sphere, and have positive weights. Both a uniform and equal-weight quadrature set UE{sub n} and a uniform and Gauss-weight quadrature set UG{sub n} are derived. These quadratures have the advantage over the standard level-symmetric LQ{sub n} quadrature sets in that the weights are positive for all orders, and the solution may be systematically converged by increasing the order of the quadrature set. As the order of the quadrature is increased the points approach a uniform continuous distribution on the unit sphere and the quadrature is invariant with respect to spatial rotations. The numerical integrals converge for continuous functions as the order of the quadrature is increased. Numerical calculations were performed to evaluate the application of the UE{sub n} quadrature set. Comparisons of the exact moments and those calculated using the UE{sub n} quadrature set demonstrate that the moment integrals are performed accurately except for distributions that are very sharply peaked along the direction of the polar axis. A series of DORT transport calculations of the >1-Mev neutron flux for a typical reactor core/pressure vessel geometry were also carried out. These calculations employed the UE{sub n} (n = 6, 10, 12, 18, and 24) quadratures and indicate that the UE{sub n} solutions have converged to within {approximately}0.5%. The UE{sub 24} solutions were also found to be more accurate than the calculations performed with the S{sub 16} level-symmetric quadratures.
Inverse sparse tracker with a locally weighted distance metric.
Wang, Dong; Lu, Huchuan; Xiao, Ziyang; Yang, Ming-Hsuan
2015-09-01
Sparse representation has been recently extensively studied for visual tracking and generally facilitates more accurate tracking results than classic methods. In this paper, we propose a sparsity-based tracking algorithm that is featured with two components: 1) an inverse sparse representation formulation and 2) a locally weighted distance metric. In the inverse sparse representation formulation, the target template is reconstructed with particles, which enables the tracker to compute the weights of all particles by solving only one l1 optimization problem and thereby provides a quite efficient model. This is in direct contrast to most previous sparse trackers that entail solving one optimization problem for each particle. However, we notice that this formulation with normal Euclidean distance metric is sensitive to partial noise like occlusion and illumination changes. To this end, we design a locally weighted distance metric to replace the Euclidean one. Similar ideas of using local features appear in other works, but only being supported by popular assumptions like local models could handle partial noise better than holistic models, without any solid theoretical analysis. In this paper, we attempt to explicitly explain it from a mathematical view. On that basis, we further propose a method to assign local weights by exploiting the temporal and spatial continuity. In the proposed method, appearance changes caused by partial occlusion and shape deformation are carefully considered, thereby facilitating accurate similarity measurement and model update. The experimental validation is conducted from two aspects: 1) self validation on key components and 2) comparison with other state-of-the-art algorithms. Results over 15 challenging sequences show that the proposed tracking algorithm performs favorably against the existing sparsity-based trackers and the other state-of-the-art methods. PMID:25935033
The bid to lose weight: impact of social media on weight perceptions, weight control and diabetes.
Das, Leah; Mohan, Ranjini; Makaya, Tafadzwa
2014-01-01
Over the last decade the internet has come to permeate every aspect of our lives. With huge leaps in accessibility of the internet via mobile personal devices such as smart cellular phones and tablets, individuals are connected to the internet virtually all the time. It is no surprise therefore that social media now dominates the lives of many people within society. The authors take a look at how social media is influencing diabetes with particular focus on weight perception, weight management and eating behaviours. The authors explore the concept of how the advertising of Size 0 models and photo-shopping of images which are easily available on line and via social media is causing an increase in the number of young people with distorted body images. This has led to an increased number of people resorting to sometimes drastic weight loss programmes. We focus on the bid for 'low-fat' consumption and highlight how this could actually be leading to an increased risk for developing diabetes or worsening the complications of diabetes. We also discuss the increase of eating disorder in diabetes related to this distorted body image. PMID:25311196
NASA Technical Reports Server (NTRS)
Sensmeier, Mark D.; Samareh, Jamshid A.
2005-01-01
An approach is proposed for the application of rapid generation of moderate-fidelity structural finite element models of air vehicle structures to allow more accurate weight estimation earlier in the vehicle design process. This should help to rapidly assess many structural layouts before the start of the preliminary design phase and eliminate weight penalties imposed when actual structure weights exceed those estimated during conceptual design. By defining the structural topology in a fully parametric manner, the structure can be mapped to arbitrary vehicle configurations being considered during conceptual design optimization. A demonstration of this process is shown for two sample aircraft wing designs.
On the importance of having accurate data for astrophysical modelling
NASA Astrophysics Data System (ADS)
Lique, Francois
2016-06-01
The Herschel telescope and the ALMA and NOEMA interferometers have opened new windows of observation for wavelengths ranging from far infrared to sub-millimeter with spatial and spectral resolutions previously unmatched. To make the most of these observations, an accurate knowledge of the physical and chemical processes occurring in the interstellar and circumstellar media is essential.In this presentation, I will discuss what are the current needs of astrophysics in terms of molecular data and I will show that accurate molecular data are crucial for the proper determination of the physical conditions in molecular clouds.First, I will focus on collisional excitation studies that are needed for molecular lines modelling beyond the Local Thermodynamic Equilibrium (LTE) approach. In particular, I will show how new collisional data for the HCN and HNC isomers, two tracers of star forming conditions, have allowed solving the problem of their respective abundance in cold molecular clouds. I will also present the last collisional data that have been computed in order to analyse new highly resolved observations provided by the ALMA interferometer.Then, I will present the calculation of accurate rate constants for the F+H2 → HF+H and Cl+H2 ↔ HCl+H reactions, which have allowed a more accurate determination of the physical conditions in diffuse molecular clouds. I will also present the recent work on the ortho-para-H2 conversion due to hydrogen exchange that allow more accurate determination of the ortho-to-para-H2 ratio in the universe and that imply a significant revision of the cooling mechanism in astrophysical media.
Accurate modeling of switched reluctance machine based on hybrid trained WNN
Song, Shoujun Ge, Lefei; Ma, Shaojie; Zhang, Man
2014-04-15
According to the strong nonlinear electromagnetic characteristics of switched reluctance machine (SRM), a novel accurate modeling method is proposed based on hybrid trained wavelet neural network (WNN) which combines improved genetic algorithm (GA) with gradient descent (GD) method to train the network. In the novel method, WNN is trained by GD method based on the initial weights obtained per improved GA optimization, and the global parallel searching capability of stochastic algorithm and local convergence speed of deterministic algorithm are combined to enhance the training accuracy, stability and speed. Based on the measured electromagnetic characteristics of a 3-phase 12/8-pole SRM, the nonlinear simulation model is built by hybrid trained WNN in Matlab. The phase current and mechanical characteristics from simulation under different working conditions meet well with those from experiments, which indicates the accuracy of the model for dynamic and static performance evaluation of SRM and verifies the effectiveness of the proposed modeling method.
[Fast food promotes weight gain].
Stender, Steen; Dyerberg, Jørn; Astrup, Arne V
2007-05-01
The total amounts of fat in a fast food menu consisting of French fries and fried Chicken Nuggets from McDonald's and KFC, respectively, bought in 35 different countries vary from 41 to 71 gram. In most countries the menu contained unacceptably high amounts of industrially-produced trans fat which contributes to an increased risk of ischaemic heart disease, weight gain, abdominal fat accumulation and type 2 diabetes. The quality of the ingredients in fast food ought to be better and the size of the portions smaller and less energy-dense so that frequent fast food meals do not increase the risk of obesity and diseases among customers. PMID:17537359
NASA Astrophysics Data System (ADS)
Bruschi, David Edward
2016-03-01
We investigate a scenario where quantum correlations affect the gravitational field. We show that quantum correlations between particles occupying different positions have an effect on the gravitational field. We find that the small perturbations induced by the entanglement depend on the amount of entanglement and vanish for vanishing quantum correlations. Our results suggest that there is a form of entanglement that has a weight, since it affects the gravitational field. This conclusion may lead towards a new understanding of the role of quantum correlations within the overlap of relativistic and quantum theories.
DR-TAMAS: Diffeomorphic Registration for Tensor Accurate Alignment of Anatomical Structures.
Irfanoglu, M Okan; Nayak, Amritha; Jenkins, Jeffrey; Hutchinson, Elizabeth B; Sadeghi, Neda; Thomas, Cibu P; Pierpaoli, Carlo
2016-05-15
In this work, we propose DR-TAMAS (Diffeomorphic Registration for Tensor Accurate alignMent of Anatomical Structures), a novel framework for intersubject registration of Diffusion Tensor Imaging (DTI) data sets. This framework is optimized for brain data and its main goal is to achieve an accurate alignment of all brain structures, including white matter (WM), gray matter (GM), and spaces containing cerebrospinal fluid (CSF). Currently most DTI-based spatial normalization algorithms emphasize alignment of anisotropic structures. While some diffusion-derived metrics, such as diffusion anisotropy and tensor eigenvector orientation, are highly informative for proper alignment of WM, other tensor metrics such as the trace or mean diffusivity (MD) are fundamental for a proper alignment of GM and CSF boundaries. Moreover, it is desirable to include information from structural MRI data, e.g., T1-weighted or T2-weighted images, which are usually available together with the diffusion data. The fundamental property of DR-TAMAS is to achieve global anatomical accuracy by incorporating in its cost function the most informative metrics locally. Another important feature of DR-TAMAS is a symmetric time-varying velocity-based transformation model, which enables it to account for potentially large anatomical variability in healthy subjects and patients. The performance of DR-TAMAS is evaluated with several data sets and compared with other widely-used diffeomorphic image registration techniques employing both full tensor information and/or DTI-derived scalar maps. Our results show that the proposed method has excellent overall performance in the entire brain, while being equivalent to the best existing methods in WM. PMID:26931817
Dryer, Rachel; Ware, Nicole
2014-01-01
Purpose: To identify beliefs held by the general public regarding causes of weight gain, weight prevention strategies, and barriers to weight management; and to examine whether such beliefs predict the actual body mass of participants. Methods: A questionnaire-based survey was administered to participants recruited from regional and metropolitan areas of Australia. This questionnaire obtained demographic information, height, weight; as well as beliefs about causes of weight gain, weight prevention strategies, and barriers to weight management. Results: The sample consisted of 376 participants (94 males, 282 females) between the ages of 18 years and 88 years (mean age = 43.25, SD = 13.64). The range and nature of the belief dimensions identified suggest that the Australian public have an understanding of the interaction between internal and external factors that impact on weight gain but also prevent successful weight management. Beliefs about prevention strategies and barriers to effective weight management were found to predict the participants’ actual body mass, even after controlling for demographic characteristics. Conclusions: The general public have a good understanding of the multiple contributing factors to weight gain and successful weight management. However, this understanding may not necessarily lead to individuals adopting the required lifestyle changes that result in achievement or maintenance of healthy weight levels. PMID:25750768
Dietary restraint and gestational weight gain
Mumford, Sunni L.; Siega-Riz, Anna Maria; Herring, Amy; Evenson, Kelly R.
2008-01-01
Objective To determine whether a history of preconceptional dieting and restrained eating was related to higher weight gains in pregnancy. Design Dieting practices were assessed among a prospective cohort of pregnant women using the Revised Restraint Scale. Women were classified on three separate subscales as restrained eaters, dieters, and weight cyclers. Subjects Participants included 1,223 women in the Pregnancy, Infection and Nutrition Study. Main outcome measures Total gestational weight gain and adequacy of weight gain (ratio of observed/expected weight gain based on Institute of Medicine (IOM) recommendations). Statistical analyses performed Multiple linear regression was used to model the two weight gain outcomes, while controlling for potential confounders including physical activity and weight gain attitudes. Results There was a positive association between each subscale and total weight gain, as well as adequacy of weight gain. Women classified as cyclers gained an average of 2 kg more than non-cyclers, and showed higher observed/expected ratios by 0.2 units. Among restrained eaters and dieters, there was a differential effect by BMI. With the exception of underweight women, all other weight status women with a history of dieting or restrained eating gained more weight during pregnancy and had higher adequacy of weight gain ratios. In contrast, underweight women with a history of restrained eating behaviors gained less weight compared to underweight women without those behaviors. Conclusions Restrained eating behaviors were associated with weight gains above the IOM recommendations for normal, overweight, and obese women, and weight gains below the recommendations for underweight women. Excessive gestational weight gain is of concern given its association with postpartum weight retention. The dietary restraint tool is useful for identifying women who would benefit from nutritional counseling prior to or during pregnancy in regards to achieving targeted
DNA barcode data accurately assign higher spider taxa.
Coddington, Jonathan A; Agnarsson, Ingi; Cheng, Ren-Chung; Čandek, Klemen; Driskell, Amy; Frick, Holger; Gregorič, Matjaž; Kostanjšek, Rok; Kropf, Christian; Kweskin, Matthew; Lokovšek, Tjaša; Pipan, Miha; Vidergar, Nina; Kuntner, Matjaž
2016-01-01
The use of unique DNA sequences as a method for taxonomic identification is no longer fundamentally controversial, even though debate continues on the best markers, methods, and technology to use. Although both existing databanks such as GenBank and BOLD, as well as reference taxonomies, are imperfect, in best case scenarios "barcodes" (whether single or multiple, organelle or nuclear, loci) clearly are an increasingly fast and inexpensive method of identification, especially as compared to manual identification of unknowns by increasingly rare expert taxonomists. Because most species on Earth are undescribed, a complete reference database at the species level is impractical in the near term. The question therefore arises whether unidentified species can, using DNA barcodes, be accurately assigned to more inclusive groups such as genera and families-taxonomic ranks of putatively monophyletic groups for which the global inventory is more complete and stable. We used a carefully chosen test library of CO1 sequences from 49 families, 313 genera, and 816 species of spiders to assess the accuracy of genus and family-level assignment. We used BLAST queries of each sequence against the entire library and got the top ten hits. The percent sequence identity was reported from these hits (PIdent, range 75-100%). Accurate assignment of higher taxa (PIdent above which errors totaled less than 5%) occurred for genera at PIdent values >95 and families at PIdent values ≥ 91, suggesting these as heuristic thresholds for accurate generic and familial identifications in spiders. Accuracy of identification increases with numbers of species/genus and genera/family in the library; above five genera per family and fifteen species per genus all higher taxon assignments were correct. We propose that using percent sequence identity between conventional barcode sequences may be a feasible and reasonably accurate method to identify animals to family/genus. However, the quality of the
DNA barcode data accurately assign higher spider taxa
Coddington, Jonathan A.; Agnarsson, Ingi; Cheng, Ren-Chung; Čandek, Klemen; Driskell, Amy; Frick, Holger; Gregorič, Matjaž; Kostanjšek, Rok; Kropf, Christian; Kweskin, Matthew; Lokovšek, Tjaša; Pipan, Miha; Vidergar, Nina
2016-01-01
The use of unique DNA sequences as a method for taxonomic identification is no longer fundamentally controversial, even though debate continues on the best markers, methods, and technology to use. Although both existing databanks such as GenBank and BOLD, as well as reference taxonomies, are imperfect, in best case scenarios “barcodes” (whether single or multiple, organelle or nuclear, loci) clearly are an increasingly fast and inexpensive method of identification, especially as compared to manual identification of unknowns by increasingly rare expert taxonomists. Because most species on Earth are undescribed, a complete reference database at the species level is impractical in the near term. The question therefore arises whether unidentified species can, using DNA barcodes, be accurately assigned to more inclusive groups such as genera and families—taxonomic ranks of putatively monophyletic groups for which the global inventory is more complete and stable. We used a carefully chosen test library of CO1 sequences from 49 families, 313 genera, and 816 species of spiders to assess the accuracy of genus and family-level assignment. We used BLAST queries of each sequence against the entire library and got the top ten hits. The percent sequence identity was reported from these hits (PIdent, range 75–100%). Accurate assignment of higher taxa (PIdent above which errors totaled less than 5%) occurred for genera at PIdent values >95 and families at PIdent values ≥ 91, suggesting these as heuristic thresholds for accurate generic and familial identifications in spiders. Accuracy of identification increases with numbers of species/genus and genera/family in the library; above five genera per family and fifteen species per genus all higher taxon assignments were correct. We propose that using percent sequence identity between conventional barcode sequences may be a feasible and reasonably accurate method to identify animals to family/genus. However, the quality of
SIMPLE AND WEIGHTED AVERAGING APPROACHES TO SCALING: WHEN CAN SPATIAL CONTEXT BE IGNORED?
Technology Transfer Automated Retrieval System (TEKTRAN)
Scaling from plots to landscapes, landscapes to regions, and regions to the globe based on simple or weighted averaging techniques can be accurate when applied to the appropriate problems. Simple averaging approaches work well when conditions are homogeneous spatially and temporally. For example, ...
ERIC Educational Resources Information Center
Davis, Shala E.; Dwyer, Gregory B.; Reed, Kristy; Bopp, Christopher; Stosic, Jelena; Shepanski, Melissa
2002-01-01
Examined the impact of the National Collegiate Athletic Association's Wrestling Weight Certification Program on weight cutting. Results indicated that during one season, team members attempted to lose significant amounts of weight. However, after the first week of competition, many regained weight. The next season, weight loss was not as dramatic,…
A More Accurate Characterization of UH-60A Pitch Link Loads Using Neural Networks
NASA Technical Reports Server (NTRS)
Kottapalli, Sesi; Aiken, Ed (Technical Monitor)
1998-01-01
A more accurate, neural-network-based characterization of the full-scale UH-60A maximum, vibratory pitch link loads (MXVPLL) was obtained. The MXVPLL data were taken from the NASA/Army UH-60A Airloads Program flight test database. This database includes data from level flights, and both simple and "complex" maneuvers. In the present context, a complex maneuver was defined as one which involved simultaneous, non-zero aircraft angle-of-bank (associated with turns) and aircraft pitch-rate (associated with a pull-up or a push-over). The present approach combines physical insight followed by the neural networks application. Since existing load factors do not represent the above-defined complex maneuver, a new, combined load factor ('p resent-load-factor') was introduced. A back-propagation type of neural network with five inputs and one output was used to characterize the UH-60A MXVPLL. The neural network inputs were as follows: rotor advance ratio, aircraft gross weight, rotor RPM, air density ratio, and the present-load-factor. The neural network output was the maximum, vibratory pitch link load (MXVPLL). It was shown that a more accurate characterization of the full-scale flight test pitch link loads can be obtained by combining physical insight with a neural-network-based approach.
Curvelet-based sampling for accurate and efficient multimodal image registration
NASA Astrophysics Data System (ADS)
Safran, M. N.; Freiman, M.; Werman, M.; Joskowicz, L.
2009-02-01
We present a new non-uniform adaptive sampling method for the estimation of mutual information in multi-modal image registration. The method uses the Fast Discrete Curvelet Transform to identify regions along anatomical curves on which the mutual information is computed. Its main advantages of over other non-uniform sampling schemes are that it captures the most informative regions, that it is invariant to feature shapes, orientations, and sizes, that it is efficient, and that it yields accurate results. Extensive evaluation on 20 validated clinical brain CT images to Proton Density (PD) and T1 and T2-weighted MRI images from the public RIRE database show the effectiveness of our method. Rigid registration accuracy measured at 10 clinical targets and compared to ground truth measurements yield a mean target registration error of 0.68mm(std=0.4mm) for CT-PD and 0.82mm(std=0.43mm) for CT-T2. This is 0.3mm (1mm) more accurate in the average (worst) case than five existing sampling methods. Our method has the lowest registration errors recorded to date for the registration of CT-PD and CT-T2 images in the RIRE website when compared to methods that were tested on at least three patient datasets.
Fast and accurate dating of nuclear events using La-140/Ba-140 isotopic activity ratio.
Yamba, Kassoum; Sanogo, Oumar; Kalinowski, Martin B; Nikkinen, Mika; Koulidiati, Jean
2016-06-01
This study reports on a fast and accurate assessment of zero time of certain nuclear events using La-140/Ba-140 isotopic activity ratio. For a non-steady nuclear fission reaction, the dating is not possible. For the hypothesis of a nuclear explosion and for a release from a steady state nuclear fission reaction the zero-times will differ. This assessment is fast, because we propose some constants that can be used directly for the calculation of zero time and its upper and lower age limits. The assessment is accurate because of the calculation of zero time using a mathematical method, namely the weighted least-squares method, to evaluate an average value of the age of a nuclear event. This was done using two databases that exhibit differences between the values of some nuclear parameters. As an example, the calculation method is applied for the detection of radionuclides La-140 and Ba-140 in May 2010 at the radionuclides station JPP37 (Okinawa Island, Japan). PMID:27058322
Gayes, Laurie A; Steele, Ric G
2015-03-01
The objective of this study was to examine the degree to which 2 measures of weight criticism, the Weight Criticism During Physical Activity (WCA) scale and the Perceptions of Teasing Scale (POTS), represent distinct constructs and in what circumstances each is most appropriately used. A community sample of 307 fourth and fifth graders completed these measures, as well as measures of health-related quality of life, physical activity engagement, and attitudes toward physical activity. Body mass index was also calculated. Results of confirmatory factor analysis indicated that the WCA scale and the POTS represented correlated but distinct constructs and related differently to measures of physical activity and weight status. Findings suggested that the WCA scale may be representing criticism regarding athletic competency, not criticism of weight status as described in the literature. The POTS subscales appear to be accurately described and used in the literature. PMID:25281194
SUMOylation in Control of Accurate Chromosome Segregation during Mitosis
Wan, Jun; Subramonian, Divya; Zhang, Xiang-Dong
2012-01-01
Posttranslational protein modification by small ubiquitin-related modifier (SUMO) has emerged as an important regulatory mechanism for chromosome segregation during mitosis. This review focuses on how SUMOylation regulates the centromere and kinetochore activities to achieve accurate chromosome segregation during mitosis. Kinetochores are assembled on the specialized chromatin domains called centromeres and serve as the sites for attaching spindle microtubule to segregate sister chromatids to daughter cells. Many proteins associated with mitotic centromeres and kinetochores have been recently found to be modified by SUMO. Although we are still at the early stage of elucidating how SUMOylation controls chromosome segregation during mitosis, a substantial progress has been achieved over the past decade. Furthermore, a major theme that has emerged from the recent studies of SUMOylation in mitosis is that both SUMO conjugation and deconjugation are critical for kinetochore assembly and disassembly. Lastly, we propose a model that SUMOylation coordinates multiple centromere and kinetochore activities to ensure accurate chromosome segregation. PMID:22812528
Accurate and robust estimation of camera parameters using RANSAC
NASA Astrophysics Data System (ADS)
Zhou, Fuqiang; Cui, Yi; Wang, Yexin; Liu, Liu; Gao, He
2013-03-01
Camera calibration plays an important role in the field of machine vision applications. The popularly used calibration approach based on 2D planar target sometimes fails to give reliable and accurate results due to the inaccurate or incorrect localization of feature points. To solve this problem, an accurate and robust estimation method for camera parameters based on RANSAC algorithm is proposed to detect the unreliability and provide the corresponding solutions. Through this method, most of the outliers are removed and the calibration errors that are the main factors influencing measurement accuracy are reduced. Both simulative and real experiments have been carried out to evaluate the performance of the proposed method and the results show that the proposed method is robust under large noise condition and quite efficient to improve the calibration accuracy compared with the original state.
Accurate Development of Thermal Neutron Scattering Cross Section Libraries
Hawari, Ayman; Dunn, Michael
2014-06-10
The objective of this project is to develop a holistic (fundamental and accurate) approach for generating thermal neutron scattering cross section libraries for a collection of important enutron moderators and reflectors. The primary components of this approach are the physcial accuracy and completeness of the generated data libraries. Consequently, for the first time, thermal neutron scattering cross section data libraries will be generated that are based on accurate theoretical models, that are carefully benchmarked against experimental and computational data, and that contain complete covariance information that can be used in propagating the data uncertainties through the various components of the nuclear design and execution process. To achieve this objective, computational and experimental investigations will be performed on a carefully selected subset of materials that play a key role in all stages of the nuclear fuel cycle.
Accurate adjoint design sensitivities for nano metal optics.
Hansen, Paul; Hesselink, Lambertus
2015-09-01
We present a method for obtaining accurate numerical design sensitivities for metal-optical nanostructures. Adjoint design sensitivity analysis, long used in fluid mechanics and mechanical engineering for both optimization and structural analysis, is beginning to be used for nano-optics design, but it fails for sharp-cornered metal structures because the numerical error in electromagnetic simulations of metal structures is highest at sharp corners. These locations feature strong field enhancement and contribute strongly to design sensitivities. By using high-accuracy FEM calculations and rounding sharp features to a finite radius of curvature we obtain highly-accurate design sensitivities for 3D metal devices. To provide a bridge to the existing literature on adjoint methods in other fields, we derive the sensitivity equations for Maxwell's equations in the PDE framework widely used in fluid mechanics. PMID:26368483
An Accurate Link Correlation Estimator for Improving Wireless Protocol Performance
Zhao, Zhiwei; Xu, Xianghua; Dong, Wei; Bu, Jiajun
2015-01-01
Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE) approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1) achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2) greatly improves the performance of protocols exploiting link correlation. PMID:25686314
Light Field Imaging Based Accurate Image Specular Highlight Removal
Wang, Haoqian; Xu, Chenxue; Wang, Xingzheng; Zhang, Yongbing; Peng, Bo
2016-01-01
Specular reflection removal is indispensable to many computer vision tasks. However, most existing methods fail or degrade in complex real scenarios for their individual drawbacks. Benefiting from the light field imaging technology, this paper proposes a novel and accurate approach to remove specularity and improve image quality. We first capture images with specularity by the light field camera (Lytro ILLUM). After accurately estimating the image depth, a simple and concise threshold strategy is adopted to cluster the specular pixels into “unsaturated” and “saturated” category. Finally, a color variance analysis of multiple views and a local color refinement are individually conducted on the two categories to recover diffuse color information. Experimental evaluation by comparison with existed methods based on our light field dataset together with Stanford light field archive verifies the effectiveness of our proposed algorithm. PMID:27253083
Local Debonding and Fiber Breakage in Composite Materials Modeled Accurately
NASA Technical Reports Server (NTRS)
Bednarcyk, Brett A.; Arnold, Steven M.
2001-01-01
A prerequisite for full utilization of composite materials in aerospace components is accurate design and life prediction tools that enable the assessment of component performance and reliability. Such tools assist both structural analysts, who design and optimize structures composed of composite materials, and materials scientists who design and optimize the composite materials themselves. NASA Glenn Research Center's Micromechanics Analysis Code with Generalized Method of Cells (MAC/GMC) software package (http://www.grc.nasa.gov/WWW/LPB/mac) addresses this need for composite design and life prediction tools by providing a widely applicable and accurate approach to modeling composite materials. Furthermore, MAC/GMC serves as a platform for incorporating new local models and capabilities that are under development at NASA, thus enabling these new capabilities to progress rapidly to a stage in which they can be employed by the code's end users.
Fixed-Wing Micro Aerial Vehicle for Accurate Corridor Mapping
NASA Astrophysics Data System (ADS)
Rehak, M.; Skaloud, J.
2015-08-01
In this study we present a Micro Aerial Vehicle (MAV) equipped with precise position and attitude sensors that together with a pre-calibrated camera enables accurate corridor mapping. The design of the platform is based on widely available model components to which we integrate an open-source autopilot, customized mass-market camera and navigation sensors. We adapt the concepts of system calibration from larger mapping platforms to MAV and evaluate them practically for their achievable accuracy. We present case studies for accurate mapping without ground control points: first for a block configuration, later for a narrow corridor. We evaluate the mapping accuracy with respect to checkpoints and digital terrain model. We show that while it is possible to achieve pixel (3-5 cm) mapping accuracy in both cases, precise aerial position control is sufficient for block configuration, the precise position and attitude control is required for corridor mapping.
Multimodal Spatial Calibration for Accurately Registering EEG Sensor Positions
Chen, Shengyong; Xiao, Gang; Li, Xiaoli
2014-01-01
This paper proposes a fast and accurate calibration method to calibrate multiple multimodal sensors using a novel photogrammetry system for fast localization of EEG sensors. The EEG sensors are placed on human head and multimodal sensors are installed around the head to simultaneously obtain all EEG sensor positions. A multiple views' calibration process is implemented to obtain the transformations of multiple views. We first develop an efficient local repair algorithm to improve the depth map, and then a special calibration body is designed. Based on them, accurate and robust calibration results can be achieved. We evaluate the proposed method by corners of a chessboard calibration plate. Experimental results demonstrate that the proposed method can achieve good performance, which can be further applied to EEG source localization applications on human brain. PMID:24803954
Accurate nuclear radii and binding energies from a chiral interaction
Ekstrom, Jan A.; Jansen, G. R.; Wendt, Kyle A.; Hagen, Gaute; Papenbrock, Thomas F.; Carlsson, Boris; Forssen, Christian; Hjorth-Jensen, M.; Navratil, Petr; Nazarewicz, Witold
2015-05-01
With the goal of developing predictive ab initio capability for light and medium-mass nuclei, two-nucleon and three-nucleon forces from chiral effective field theory are optimized simultaneously to low-energy nucleon-nucleon scattering data, as well as binding energies and radii of few-nucleon systems and selected isotopes of carbon and oxygen. Coupled-cluster calculations based on this interaction, named NNLOsat, yield accurate binding energies and radii of nuclei up to 40Ca, and are consistent with the empirical saturation point of symmetric nuclear matter. In addition, the low-lying collective Jπ=3- states in 16O and 40Ca are described accurately, while spectra for selected p- and sd-shellmore » nuclei are in reasonable agreement with experiment.« less
Method for Accurately Calibrating a Spectrometer Using Broadband Light
NASA Technical Reports Server (NTRS)
Simmons, Stephen; Youngquist, Robert
2011-01-01
A novel method has been developed for performing very fine calibration of a spectrometer. This process is particularly useful for modern miniature charge-coupled device (CCD) spectrometers where a typical factory wavelength calibration has been performed and a finer, more accurate calibration is desired. Typically, the factory calibration is done with a spectral line source that generates light at known wavelengths, allowing specific pixels in the CCD array to be assigned wavelength values. This method is good to about 1 nm across the spectrometer s wavelength range. This new method appears to be accurate to about 0.1 nm, a factor of ten improvement. White light is passed through an unbalanced Michelson interferometer, producing an optical signal with significant spectral variation. A simple theory can be developed to describe this spectral pattern, so by comparing the actual spectrometer output against this predicted pattern, errors in the wavelength assignment made by the spectrometer can be determined.
Accurate parameter estimation for unbalanced three-phase system.
Chen, Yuan; So, Hing Cheung
2014-01-01
Smart grid is an intelligent power generation and control console in modern electricity networks, where the unbalanced three-phase power system is the commonly used model. Here, parameter estimation for this system is addressed. After converting the three-phase waveforms into a pair of orthogonal signals via the α β-transformation, the nonlinear least squares (NLS) estimator is developed for accurately finding the frequency, phase, and voltage parameters. The estimator is realized by the Newton-Raphson scheme, whose global convergence is studied in this paper. Computer simulations show that the mean square error performance of NLS method can attain the Cramér-Rao lower bound. Moreover, our proposal provides more accurate frequency estimation when compared with the complex least mean square (CLMS) and augmented CLMS. PMID:25162056
Accurate nuclear radii and binding energies from a chiral interaction
Ekstrom, Jan A.; Jansen, G. R.; Wendt, Kyle A.; Hagen, Gaute; Papenbrock, Thomas F.; Carlsson, Boris; Forssen, Christian; Hjorth-Jensen, M.; Navratil, Petr; Nazarewicz, Witold
2015-05-01
With the goal of developing predictive ab initio capability for light and medium-mass nuclei, two-nucleon and three-nucleon forces from chiral effective field theory are optimized simultaneously to low-energy nucleon-nucleon scattering data, as well as binding energies and radii of few-nucleon systems and selected isotopes of carbon and oxygen. Coupled-cluster calculations based on this interaction, named NNLO_{sat}, yield accurate binding energies and radii of nuclei up to ^{40}Ca, and are consistent with the empirical saturation point of symmetric nuclear matter. In addition, the low-lying collective J^{π}=3^{-} states in ^{16}O and ^{40}Ca are described accurately, while spectra for selected p- and sd-shell nuclei are in reasonable agreement with experiment.
An accurate link correlation estimator for improving wireless protocol performance.
Zhao, Zhiwei; Xu, Xianghua; Dong, Wei; Bu, Jiajun
2015-01-01
Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE) approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1) achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2) greatly improves the performance of protocols exploiting link correlation. PMID:25686314
Groundtruth approach to accurate quantitation of fluorescence microarrays
Mascio-Kegelmeyer, L; Tomascik-Cheeseman, L; Burnett, M S; van Hummelen, P; Wyrobek, A J
2000-12-01
To more accurately measure fluorescent signals from microarrays, we calibrated our acquisition and analysis systems by using groundtruth samples comprised of known quantities of red and green gene-specific DNA probes hybridized to cDNA targets. We imaged the slides with a full-field, white light CCD imager and analyzed them with our custom analysis software. Here we compare, for multiple genes, results obtained with and without preprocessing (alignment, color crosstalk compensation, dark field subtraction, and integration time). We also evaluate the accuracy of various image processing and analysis techniques (background subtraction, segmentation, quantitation and normalization). This methodology calibrates and validates our system for accurate quantitative measurement of microarrays. Specifically, we show that preprocessing the images produces results significantly closer to the known ground-truth for these samples.
Multimodal spatial calibration for accurately registering EEG sensor positions.
Zhang, Jianhua; Chen, Jian; Chen, Shengyong; Xiao, Gang; Li, Xiaoli
2014-01-01
This paper proposes a fast and accurate calibration method to calibrate multiple multimodal sensors using a novel photogrammetry system for fast localization of EEG sensors. The EEG sensors are placed on human head and multimodal sensors are installed around the head to simultaneously obtain all EEG sensor positions. A multiple views' calibration process is implemented to obtain the transformations of multiple views. We first develop an efficient local repair algorithm to improve the depth map, and then a special calibration body is designed. Based on them, accurate and robust calibration results can be achieved. We evaluate the proposed method by corners of a chessboard calibration plate. Experimental results demonstrate that the proposed method can achieve good performance, which can be further applied to EEG source localization applications on human brain. PMID:24803954
Note-accurate audio segmentation based on MPEG-7
NASA Astrophysics Data System (ADS)
Wellhausen, Jens
2003-12-01
Segmenting audio data into the smallest musical components is the basis for many further meta data extraction algorithms. For example, an automatic music transcription system needs to know where the exact boundaries of each tone are. In this paper a note accurate audio segmentation algorithm based on MPEG-7 low level descriptors is introduced. For a reliable detection of different notes, both features in the time and the frequency domain are used. Because of this, polyphonic instrument mixes and even melodies characterized by human voices can be examined with this alogrithm. For testing and verification of the note accurate segmentation, a simple music transcription system was implemented. The dominant frequency within each segment is used to build a MIDI file representing the processed audio data.
Ordaz-Ortiz, José Juan; Foukaraki, Sofia; Terry, Leon Alexander
2015-01-01
Plant hormones are important molecules which at low concentration can regulate various physiological processes. Mass spectrometry has become a powerful technique for the quantification of multiple classes of plant hormones because of its high sensitivity and selectivity. We developed a new ultrahigh pressure liquid chromatography–full-scan high-definition accurate mass spectrometry method, for simultaneous determination of abscisic acid and four metabolites phaseic acid, dihydrophaseic acid, 7′-hydroxy-abscisic acid and abscisic acid glucose ester, cytokinins zeatin, zeatin riboside, gibberellins (GA1, GA3, GA4 and GA7) and indole-3-acetyl-L-aspartic acid. We measured the amount of plant hormones in the flesh and skin of two processing potato cvs. Sylvana and Russet Burbank stored for up to 30 weeks at 6 °C under ambient air conditions. Herein, we report for the first time that abscisic acid glucose ester seems to accumulate in the skin of potato tubers throughout storage time. The method achieved a lowest limit of detection of 0.22 ng g−1 of dry weight and a limit of quantification of 0.74 ng g−1 dry weight (zeatin riboside), and was able to recover, detect and quantify a total of 12 plant hormones spiked on flesh and skin of potato tubers. In addition, the mass accuracy for all compounds (<5 ppm) was evaluated. PMID:26504563
NASA Astrophysics Data System (ADS)
Little, James L.; Cleven, Curtis D.; Brown, Stacy D.
2011-02-01
In many cases, an unknown to an investigator is actually known in the chemical literature. We refer to these types of compounds as "known unknowns." Chemical Abstracts Service (CAS) Registry is a particularly good source of these substances as it contains over 54 million entries. Accurate mass measurements can be used to query the CAS Registry by either molecular formulae or average molecular weights. Searching the database by the web-based version of SciFinder is the preferred approach when molecular formulae are available. However, if a definitive molecular formula cannot be ascertained, searching the database with STN Express by average molecular weights is a viable alternative. The results from either approach are refined by employing the number of associated references or minimal sample history as orthogonal filters. These approaches were shown to be successful in identifying "known unknowns" noted in LC-MS and even GC-MS analyses in our laboratory. In addition, they were demonstrated in the identification of a variety of compounds of interest to others.
Accurate Method for Determining Adhesion of Cantilever Beams
Michalske, T.A.; de Boer, M.P.
1999-01-08
Using surface micromachined samples, we demonstrate the accurate measurement of cantilever beam adhesion by using test structures which are adhered over long attachment lengths. We show that this configuration has a deep energy well, such that a fracture equilibrium is easily reached. When compared to the commonly used method of determining the shortest attached beam, the present method is much less sensitive to variations in surface topography or to details of capillary drying.
Multigrid time-accurate integration of Navier-Stokes equations
NASA Technical Reports Server (NTRS)
Arnone, Andrea; Liou, Meng-Sing; Povinelli, Louis A.
1993-01-01
Efficient acceleration techniques typical of explicit steady-state solvers are extended to time-accurate calculations. Stability restrictions are greatly reduced by means of a fully implicit time discretization. A four-stage Runge-Kutta scheme with local time stepping, residual smoothing, and multigridding is used instead of traditional time-expensive factorizations. Some applications to natural and forced unsteady viscous flows show the capability of the procedure.
Shock Emergence in Supernovae: Limiting Cases and Accurate Approximations
NASA Astrophysics Data System (ADS)
Ro, Stephen; Matzner, Christopher D.
2013-08-01
We examine the dynamics of accelerating normal shocks in stratified planar atmospheres, providing accurate fitting formulae for the scaling index relating shock velocity to the initial density and for the post-shock acceleration factor as functions of the polytropic and adiabatic indices which parameterize the problem. In the limit of a uniform initial atmosphere, there are analytical formulae for these quantities. In the opposite limit of a very steep density gradient, the solutions match the outcome of shock acceleration in exponential atmospheres.
SHOCK EMERGENCE IN SUPERNOVAE: LIMITING CASES AND ACCURATE APPROXIMATIONS
Ro, Stephen; Matzner, Christopher D.
2013-08-10
We examine the dynamics of accelerating normal shocks in stratified planar atmospheres, providing accurate fitting formulae for the scaling index relating shock velocity to the initial density and for the post-shock acceleration factor as functions of the polytropic and adiabatic indices which parameterize the problem. In the limit of a uniform initial atmosphere, there are analytical formulae for these quantities. In the opposite limit of a very steep density gradient, the solutions match the outcome of shock acceleration in exponential atmospheres.
A method for producing large, accurate, economical female molds
Guenter, A.; Guenter, B.
1996-11-01
A process in which lightweight, highly accurate, economical molds can be produced for prototype and low production runs of large parts for use in composites molding has been developed. This has been achieved by developing existing milling technology, using new materials and innovative material applications to CNC mill large female molds directly. Any step that can be eliminated in the mold building process translates into savings in tooling costs through reduced labor and material requirements.
Accurate far-infrared rotational frequencies of carbon monoxide
NASA Technical Reports Server (NTRS)
Varberg, Thomas D.; Evenson, Kenneth M.
1992-01-01
This study presents high-resolution measurements of the pure rotational absorption spectrum of CO in its ground state for the range J arcsec - 5-37. A least-squares fit to this data set, augmented by previous microwave measurements of the J arcsec = 0-4 rotational transitions in the literature, determined accurate values for the molecular constants. A table of calculated CO rotational frequencies is provided for the range J arcsec = 0-45.
A robust and accurate formulation of molecular and colloidal electrostatics.
Sun, Qiang; Klaseboer, Evert; Chan, Derek Y C
2016-08-01
This paper presents a re-formulation of the boundary integral method for the Debye-Hückel model of molecular and colloidal electrostatics that removes the mathematical singularities that have to date been accepted as an intrinsic part of the conventional boundary integral equation method. The essence of the present boundary regularized integral equation formulation consists of subtracting a known solution from the conventional boundary integral method in such a way as to cancel out the singularities associated with the Green's function. This approach better reflects the non-singular physical behavior of the systems on boundaries with the benefits of the following: (i) the surface integrals can be evaluated accurately using quadrature without any need to devise special numerical integration procedures, (ii) being able to use quadratic or spline function surface elements to represent the surface more accurately and the variation of the functions within each element is represented to a consistent level of precision by appropriate interpolation functions, (iii) being able to calculate electric fields, even at boundaries, accurately and directly from the potential without having to solve hypersingular integral equations and this imparts high precision in calculating the Maxwell stress tensor and consequently, intermolecular or colloidal forces, (iv) a reliable way to handle geometric configurations in which different parts of the boundary can be very close together without being affected by numerical instabilities, therefore potentials, fields, and forces between surfaces can be found accurately at surface separations down to near contact, and (v) having the simplicity of a formulation that does not require complex algorithms to handle singularities will result in significant savings in coding effort and in the reduction of opportunities for coding errors. These advantages are illustrated using examples drawn from molecular and colloidal electrostatics. PMID:27497538
Strategy Guideline. Accurate Heating and Cooling Load Calculations
Burdick, Arlan
2011-06-01
This guide presents the key criteria required to create accurate heating and cooling load calculations and offers examples of the implications when inaccurate adjustments are applied to the HVAC design process. The guide shows, through realistic examples, how various defaults and arbitrary safety factors can lead to significant increases in the load estimate. Emphasis is placed on the risks incurred from inaccurate adjustments or ignoring critical inputs of the load calculation.
A time-accurate multiple-grid algorithm
NASA Technical Reports Server (NTRS)
Jespersen, D. C.
1985-01-01
A time-accurate multiple-grid algorithm is described. The algorithm allows one to take much larger time steps with an explicit time-marching scheme than would otherwise be the case. Sample calculations of a scalar advection equation and the Euler equations for an oscillating airfoil are shown. For the oscillating airfoil, time steps an order of magnitude larger than the single-grid algorithm are possible.
Accurate equilibrium structures of fluoro- and chloroderivatives of methane
NASA Astrophysics Data System (ADS)
Vogt, Natalja; Demaison, Jean; Rudolph, Heinz Dieter
2014-11-01
This work is a systematic study of molecular structure of fluoro-, chloro-, and fluorochloromethanes. For the first time, the accurate ab initio structure is computed for 10 molecules (CF4, CClF3, CCl2F2, CCl3F, CHClF2, CHCl2F, CH2F2, CH2ClF, CH2Cl2, and CCl4) at the coupled cluster level of electronic structure theory including single and double excitations augmented by a perturbational estimate of the effects of connected triple excitations [CCSD(T)] with all electrons being correlated and Gaussian basis sets of at least quadruple-ζ quality. Furthermore, when possible, namely for the molecules CH2F2, CH2Cl2, CH2ClF, CHClF2, and CCl2F2, accurate semi-experimental equilibrium (rSEe) structure has also been determined. This is achieved through a least-squares structural refinement procedure based on the equilibrium rotational constants of all available isotopomers, determined by correcting the experimental ground-state rotational constants with computed ab initio vibration-rotation interaction constants and electronic g-factors. The computed and semi-experimental equilibrium structures are in excellent agreement with each other, but the rSEe structure is generally more accurate, in particular for the CF and CCl bond lengths. The carbon-halogen bond length is discussed within the framework of the ligand close-packing model as a function of the atomic charges. For this purpose, the accurate equilibrium structures of some other molecules with alternative ligands, such as CH3Li, CF3CCH, and CF3CN, are also computed.
Accurate Insertion Loss Measurements of the Juno Patch Array Antennas
NASA Technical Reports Server (NTRS)
Chamberlain, Neil; Chen, Jacqueline; Hodges, Richard; Demas, John
2010-01-01
This paper describes two independent methods for estimating the insertion loss of patch array antennas that were developed for the Juno Microwave Radiometer instrument. One method is based principally on pattern measurements while the other method is based solely on network analyzer measurements. The methods are accurate to within 0.1 dB for the measured antennas and show good agreement (to within 0.1dB) of separate radiometric measurements.
Accurate method for determining adhesion of cantilever beams
de Boer, M.P.; Michalske, T.A.
1999-07-01
Using surface micromachined samples, we demonstrate the accurate measurement of cantilever beam adhesion by using test structures which are adhered over long attachment lengths. We show that this configuration has a deep energy well, such that a fracture equilibrium is easily reached. When compared to the commonly used method of determining the shortest attached beam, the present method is much less sensitive to variations in surface topography or to details of capillary drying. {copyright} {ital 1999 American Institute of Physics.}
A robust and accurate formulation of molecular and colloidal electrostatics
NASA Astrophysics Data System (ADS)
Sun, Qiang; Klaseboer, Evert; Chan, Derek Y. C.
2016-08-01
This paper presents a re-formulation of the boundary integral method for the Debye-Hückel model of molecular and colloidal electrostatics that removes the mathematical singularities that have to date been accepted as an intrinsic part of the conventional boundary integral equation method. The essence of the present boundary regularized integral equation formulation consists of subtracting a known solution from the conventional boundary integral method in such a way as to cancel out the singularities associated with the Green's function. This approach better reflects the non-singular physical behavior of the systems on boundaries with the benefits of the following: (i) the surface integrals can be evaluated accurately using quadrature without any need to devise special numerical integration procedures, (ii) being able to use quadratic or spline function surface elements to represent the surface more accurately and the variation of the functions within each element is represented to a consistent level of precision by appropriate interpolation functions, (iii) being able to calculate electric fields, even at boundaries, accurately and directly from the potential without having to solve hypersingular integral equations and this imparts high precision in calculating the Maxwell stress tensor and consequently, intermolecular or colloidal forces, (iv) a reliable way to handle geometric configurations in which different parts of the boundary can be very close together without being affected by numerical instabilities, therefore potentials, fields, and forces between surfaces can be found accurately at surface separations down to near contact, and (v) having the simplicity of a formulation that does not require complex algorithms to handle singularities will result in significant savings in coding effort and in the reduction of opportunities for coding errors. These advantages are illustrated using examples drawn from molecular and colloidal electrostatics.
Water wave model with accurate dispersion and vertical vorticity
NASA Astrophysics Data System (ADS)
Bokhove, Onno
2010-05-01
Cotter and Bokhove (Journal of Engineering Mathematics 2010) derived a variational water wave model with accurate dispersion and vertical vorticity. In one limit, it leads to Luke's variational principle for potential flow water waves. In the another limit it leads to the depth-averaged shallow water equations including vertical vorticity. Presently, focus will be put on the Hamiltonian formulation of the variational model and its boundary conditions.
Strategy Guideline: Accurate Heating and Cooling Load Calculations
Burdick, A.
2011-06-01
This guide presents the key criteria required to create accurate heating and cooling load calculations and offers examples of the implications when inaccurate adjustments are applied to the HVAC design process. The guide shows, through realistic examples, how various defaults and arbitrary safety factors can lead to significant increases in the load estimate. Emphasis is placed on the risks incurred from inaccurate adjustments or ignoring critical inputs of the load calculation.
Byeon, Haewon
2015-01-01
Purpose Although distortion of weight perceptions has been known as a risk factor for adolescent depression, little has been known about the relationship between weight misperception patterns and depressive symptoms. This study explored the relationship between distortion of weight misperception patterns and depressive symptoms in Korean adolescents. Methods The subjects of this study were 109,373 middle school students who participated in the Korea Youth Risk Behavior Web-based Survey (KYRBWS) from 2011 to 2013. By comparing the difference between Body Mass Index (BMI) and subjective perceptions of body weight, misperceptions of weight were classified into two categories: misperception of underweight and misperception of overweight. Results When confounding variables were adjusted, the results of the logistic regression analysis revealed that male students who perceived themselves as underweight despite their normal weight were 110% more likely to have depressive symptoms (OR = 1.10, 95% CI: 1.03–1.18) than male students with accurate weight perceptions. On the contrary, for female students, misperceptions of underweight had no significant relationship with depression symptoms. Regarding misperceptions of overweight, female students who perceived themselves as overweight despite their normal weight were 107% (OR = 1.07, 95% CI: 1.02–1.11) more likely to have depressive symptoms than female students with accurate weight perceptions. Moreover, female students who perceived themselves as overweight when they were underweight were 137% (OR = 1.37, 95% CI: 1.18–1.58) more likely to have depressive symptoms. Conclusion Male students who underestimate their body weight and female students who overestimate their body weight were at a greater risk of depression emotions than students with accurate weight perceptions. PMID:26313680
Lim, Hyunjung; Wang, Youfa
2013-01-01
Objective Examine body weight misperception and its association with health-related factors among South Korean adolescents. Design and Methods The 2009 Korea Youth Risk Behavior Web-based Survey data from 72,399 adolescents aged 12–18 years were used. Based on agreements between weight status assessed according to self-reported BMI and self-perceived weight status, adolescents were classified as weight underestimate, accurate, and overestimate. Logistic regression models examined the associations controlling for covariates. Results Over 50% adolescents misclassified their own weight status: underestimation(23.4%) and overestimation(26.8%). Boys had a higher underestimation rate than girls(30.3% vs. 15.6%) and a lower overestimation rate(21.3% vs. 33.0%). In girls, overestimation was higher in high-income families and well-educated parents(41.0%). Compared to those with accurate weight perception, participants who underestimated their weight were more likely to have an unhealthy diet as indicated by higher daily consumption(≥ once/day) of fast food[OR=1.18(1.00,1.39)] and unhealthy snacks[OR=1.11(1.03,1.19)]. Girls who overestimated their weight had more screen time[≥2 hours/day, OR=1.12(1.03,1.22)]. Participants who overestimated their weight were more likely to be stressed[OR=1.24(1.18,1.31)] and depressed[OR=1.18(1.21,1.25)]. Conclusions Over half of Korean adolescents had misperception on own weight status, the rates varied by gender and socio-economic status. Weight misperception is associated with health-related outcomes compared to peers with accurate perceptions about own weight status. PMID:23512737
Accurate thermoelastic tensor and acoustic velocities of NaCl
NASA Astrophysics Data System (ADS)
Marcondes, Michel L.; Shukla, Gaurav; da Silveira, Pedro; Wentzcovitch, Renata M.
2015-12-01
Despite the importance of thermoelastic properties of minerals in geology and geophysics, their measurement at high pressures and temperatures are still challenging. Thus, ab initio calculations are an essential tool for predicting these properties at extreme conditions. Owing to the approximate description of the exchange-correlation energy, approximations used in calculations of vibrational effects, and numerical/methodological approximations, these methods produce systematic deviations. Hybrid schemes combining experimental data and theoretical results have emerged as a way to reconcile available information and offer more reliable predictions at experimentally inaccessible thermodynamics conditions. Here we introduce a method to improve the calculated thermoelastic tensor by using highly accurate thermal equation of state (EoS). The corrective scheme is general, applicable to crystalline solids with any symmetry, and can produce accurate results at conditions where experimental data may not exist. We apply it to rock-salt-type NaCl, a material whose structural properties have been challenging to describe accurately by standard ab initio methods and whose acoustic/seismic properties are important for the gas and oil industry.
Accurate and occlusion-robust multi-view stereo
NASA Astrophysics Data System (ADS)
Zhu, Zhaokun; Stamatopoulos, Christos; Fraser, Clive S.
2015-11-01
This paper proposes an accurate multi-view stereo method for image-based 3D reconstruction that features robustness in the presence of occlusions. The new method offers improvements in dealing with two fundamental image matching problems. The first concerns the selection of the support window model, while the second centers upon accurate visibility estimation for each pixel. The support window model is based on an approximate 3D support plane described by a depth and two per-pixel depth offsets. For the visibility estimation, the multi-view constraint is initially relaxed by generating separate support plane maps for each support image using a modified PatchMatch algorithm. Then the most likely visible support image, which represents the minimum visibility of each pixel, is extracted via a discrete Markov Random Field model and it is further augmented by parameter clustering. Once the visibility is estimated, multi-view optimization taking into account all redundant observations is conducted to achieve optimal accuracy in the 3D surface generation for both depth and surface normal estimates. Finally, multi-view consistency is utilized to eliminate any remaining observational outliers. The proposed method is experimentally evaluated using well-known Middlebury datasets, and results obtained demonstrate that it is amongst the most accurate of the methods thus far reported via the Middlebury MVS website. Moreover, the new method exhibits a high completeness rate.
Method and apparatus for accurately manipulating an object during microelectrophoresis
Parvin, Bahram A.; Maestre, Marcos F.; Fish, Richard H.; Johnston, William E.
1997-01-01
An apparatus using electrophoresis provides accurate manipulation of an object on a microscope stage for further manipulations add reactions. The present invention also provides an inexpensive and easily accessible means to move an object without damage to the object. A plurality of electrodes are coupled to the stage in an array whereby the electrode array allows for distinct manipulations of the electric field for accurate manipulations of the object. There is an electrode array control coupled to the plurality of electrodes for manipulating the electric field. In an alternative embodiment, a chamber is provided on the stage to hold the object. The plurality of electrodes are positioned in the chamber, and the chamber is filled with fluid. The system can be automated using visual servoing, which manipulates the control parameters, i.e., x, y stage, applying the field, etc., after extracting the significant features directly from image data. Visual servoing includes an imaging device and computer system to determine the location of the object. A second stage having a plurality of tubes positioned on top of the second stage, can be accurately positioned by visual servoing so that one end of one of the plurality of tubes surrounds at least part of the object on the first stage.
Method and apparatus for accurately manipulating an object during microelectrophoresis
Parvin, B.A.; Maestre, M.F.; Fish, R.H.; Johnston, W.E.
1997-09-23
An apparatus using electrophoresis provides accurate manipulation of an object on a microscope stage for further manipulations and reactions. The present invention also provides an inexpensive and easily accessible means to move an object without damage to the object. A plurality of electrodes are coupled to the stage in an array whereby the electrode array allows for distinct manipulations of the electric field for accurate manipulations of the object. There is an electrode array control coupled to the plurality of electrodes for manipulating the electric field. In an alternative embodiment, a chamber is provided on the stage to hold the object. The plurality of electrodes are positioned in the chamber, and the chamber is filled with fluid. The system can be automated using visual servoing, which manipulates the control parameters, i.e., x, y stage, applying the field, etc., after extracting the significant features directly from image data. Visual servoing includes an imaging device and computer system to determine the location of the object. A second stage having a plurality of tubes positioned on top of the second stage, can be accurately positioned by visual servoing so that one end of one of the plurality of tubes surrounds at least part of the object on the first stage. 11 figs.
Accurate pose estimation using single marker single camera calibration system
NASA Astrophysics Data System (ADS)
Pati, Sarthak; Erat, Okan; Wang, Lejing; Weidert, Simon; Euler, Ekkehard; Navab, Nassir; Fallavollita, Pascal
2013-03-01
Visual marker based tracking is one of the most widely used tracking techniques in Augmented Reality (AR) applications. Generally, multiple square markers are needed to perform robust and accurate tracking. Various marker based methods for calibrating relative marker poses have already been proposed. However, the calibration accuracy of these methods relies on the order of the image sequence and pre-evaluation of pose-estimation errors, making the method offline. Several studies have shown that the accuracy of pose estimation for an individual square marker depends on camera distance and viewing angle. We propose a method to accurately model the error in the estimated pose and translation of a camera using a single marker via an online method based on the Scaled Unscented Transform (SUT). Thus, the pose estimation for each marker can be estimated with highly accurate calibration results independent of the order of image sequences compared to cases when this knowledge is not used. This removes the need for having multiple markers and an offline estimation system to calculate camera pose in an AR application.
Accurate projector calibration method by using an optical coaxial camera.
Huang, Shujun; Xie, Lili; Wang, Zhangying; Zhang, Zonghua; Gao, Feng; Jiang, Xiangqian
2015-02-01
Digital light processing (DLP) projectors have been widely utilized to project digital structured-light patterns in 3D imaging systems. In order to obtain accurate 3D shape data, it is important to calibrate DLP projectors to obtain the internal parameters. The existing projector calibration methods have complicated procedures or low accuracy of the obtained parameters. This paper presents a novel method to accurately calibrate a DLP projector by using an optical coaxial camera. The optical coaxial geometry is realized by a plate beam splitter, so the DLP projector can be treated as a true inverse camera. A plate having discrete markers on the surface is used to calibrate the projector. The corresponding projector pixel coordinate of each marker on the plate is determined by projecting vertical and horizontal sinusoidal fringe patterns on the plate surface and calculating the absolute phase. The internal parameters of the DLP projector are obtained by the corresponding point pair between the projector pixel coordinate and the world coordinate of discrete markers. Experimental results show that the proposed method can accurately calibrate the internal parameters of a DLP projector. PMID:25967789
Can blind persons accurately assess body size from the voice?
Pisanski, Katarzyna; Oleszkiewicz, Anna; Sorokowska, Agnieszka
2016-04-01
Vocal tract resonances provide reliable information about a speaker's body size that human listeners use for biosocial judgements as well as speech recognition. Although humans can accurately assess men's relative body size from the voice alone, how this ability is acquired remains unknown. In this study, we test the prediction that accurate voice-based size estimation is possible without prior audiovisual experience linking low frequencies to large bodies. Ninety-one healthy congenitally or early blind, late blind and sighted adults (aged 20-65) participated in the study. On the basis of vowel sounds alone, participants assessed the relative body sizes of male pairs of varying heights. Accuracy of voice-based body size assessments significantly exceeded chance and did not differ among participants who were sighted, or congenitally blind or who had lost their sight later in life. Accuracy increased significantly with relative differences in physical height between men, suggesting that both blind and sighted participants used reliable vocal cues to size (i.e. vocal tract resonances). Our findings demonstrate that prior visual experience is not necessary for accurate body size estimation. This capacity, integral to both nonverbal communication and speech perception, may be present at birth or may generalize from broader cross-modal correspondences. PMID:27095264
Accurate forced-choice recognition without awareness of memory retrieval.
Voss, Joel L; Baym, Carol L; Paller, Ken A
2008-06-01
Recognition confidence and the explicit awareness of memory retrieval commonly accompany accurate responding in recognition tests. Memory performance in recognition tests is widely assumed to measure explicit memory, but the generality of this assumption is questionable. Indeed, whether recognition in nonhumans is always supported by explicit memory is highly controversial. Here we identified circumstances wherein highly accurate recognition was unaccompanied by hallmark features of explicit memory. When memory for kaleidoscopes was tested using a two-alternative forced-choice recognition test with similar foils, recognition was enhanced by an attentional manipulation at encoding known to degrade explicit memory. Moreover, explicit recognition was most accurate when the awareness of retrieval was absent. These dissociations between accuracy and phenomenological features of explicit memory are consistent with the notion that correct responding resulted from experience-dependent enhancements of perceptual fluency with specific stimuli--the putative mechanism for perceptual priming effects in implicit memory tests. This mechanism may contribute to recognition performance in a variety of frequently-employed testing circumstances. Our results thus argue for a novel view of recognition, in that analyses of its neurocognitive foundations must take into account the potential for both (1) recognition mechanisms allied with implicit memory and (2) recognition mechanisms allied with explicit memory. PMID:18519546
Differential equation based method for accurate approximations in optimization
NASA Technical Reports Server (NTRS)
Pritchard, Jocelyn I.; Adelman, Howard M.
1990-01-01
This paper describes a method to efficiently and accurately approximate the effect of design changes on structural response. The key to this new method is to interpret sensitivity equations as differential equations that may be solved explicitly for closed form approximations, hence, the method is denoted the Differential Equation Based (DEB) method. Approximations were developed for vibration frequencies, mode shapes and static displacements. The DEB approximation method was applied to a cantilever beam and results compared with the commonly-used linear Taylor series approximations and exact solutions. The test calculations involved perturbing the height, width, cross-sectional area, tip mass, and bending inertia of the beam. The DEB method proved to be very accurate, and in msot cases, was more accurate than the linear Taylor series approximation. The method is applicable to simultaneous perturbation of several design variables. Also, the approximations may be used to calculate other system response quantities. For example, the approximations for displacement are used to approximate bending stresses.
Accurate thermochemistry for medium-sized and large molecules
Raghavachari, K.; Stefanov, B.B.; Curtiss, L.A.
1997-12-31
Accurate techniques such as Gaussian-2 (G2) theory have been proposed in recent years to evaluate the thermochemistry of small molecules from first-principles. However, as the molecules get larger, the errors in G2 theory and similar approaches tend to accumulate. For example, the computed heats of formation of benzene and naphthalene with G2 and G2(MP2) theories, respectively, have errors of 3.9 and 7.2 kcal/mol. In this work, we explore strategies for computing accurate heats of formation for medium-sized and large molecules. In our first scheme, G2 theory is combined with isodesmic bond separation reaction energies to yield accurate thermochemistry for larger molecules. For a test set of 40 molecules composed of H, C, O, and N, our method yields enthalpies of formation, {Delta}H{sub f}{sup 0}(298 K), with a mean absolute deviation from experiment of only 0.5 kcal/mol. This is an improvement of a factor of three over the deviation of 1.5 kcal/mol seen in standard G2 theory.
Accurately measuring volcanic plume velocity with multiple UV spectrometers
Williams-Jones, G.; Horton, K.A.; Elias, T.; Garbeil, H.; Mouginis-Mark, P. J.; Sutton, A.J.; Harris, A.J.L.
2006-01-01
A fundamental problem with all ground-based remotely sensed measurements of volcanic gas flux is the difficulty in accurately measuring the velocity of the gas plume. Since a representative wind speed and direction are used as proxies for the actual plume velocity, there can be considerable uncertainty in reported gas flux values. Here we present a method that uses at least two time-synchronized simultaneously recording UV spectrometers (FLYSPECs) placed a known distance apart. By analyzing the time varying structure of SO2 concentration signals at each instrument, the plume velocity can accurately be determined. Experiments were conducted on Ki??lauea (USA) and Masaya (Nicaragua) volcanoes in March and August 2003 at plume velocities between 1 and 10 m s-1. Concurrent ground-based anemometer measurements differed from FLYSPEC-measured plume speeds by up to 320%. This multi-spectrometer method allows for the accurate remote measurement of plume velocity and can therefore greatly improve the precision of volcanic or industrial gas flux measurements. ?? Springer-Verlag 2006.
Can clinicians accurately assess esophageal dilation without fluoroscopy?
Bailey, A D; Goldner, F
1990-01-01
This study questioned whether clinicians could determine the success of esophageal dilation accurately without the aid of fluoroscopy. Twenty patients were enrolled with the diagnosis of distal esophageal stenosis, including benign peptic stricture (17), Schatski's ring (2), and squamous cell carcinoma of the esophagus (1). Dilation attempts using only Maloney dilators were monitored fluoroscopically by the principle investigator, the physician and patient being unaware of the findings. Physicians then predicted whether or not their dilations were successful, and they examined various features to determine their usefulness in predicting successful dilation. They were able to predict successful dilation accurately in 97% of the cases studied; however, their predictions of unsuccessful dilation were correct only 60% of the time. Features helpful in predicting passage included easy passage of the dilator (98%) and the patient feeling the dilator in the stomach (95%). Excessive resistance suggesting unsuccessful passage was an unreliable feature and was often due to the dilator curling in the stomach. When Maloney dilators are used to dilate simple distal strictures, if the physician predicts successful passage, he is reliably accurate without the use of fluoroscopy; however, if unsuccessful passage is suspected, fluoroscopy must be used for confirmation. PMID:2210278
Efficient and accurate computation of generalized singular-value decompositions
NASA Astrophysics Data System (ADS)
Drmac, Zlatko
2001-11-01
We present a new family of algorithms for accurate floating--point computation of the singular value decomposition (SVD) of various forms of products (quotients) of two or three matrices. The main goal of such an algorithm is to compute all singular values to high relative accuracy. This means that we are seeking guaranteed number of accurate digits even in the smallest singular values. We also want to achieve computational efficiency, while maintaining high accuracy. To illustrate, consider the SVD of the product A=BTSC. The new algorithm uses certain preconditioning (based on diagonal scalings, the LU and QR factorizations) to replace A with A'=(B')TS'C', where A and A' have the same singular values and the matrix A' is computed explicitly. Theoretical analysis and numerical evidence show that, in the case of full rank B, C, S, the accuracy of the new algorithm is unaffected by replacing B, S, C with, respectively, D1B, D2SD3, D4C, where Di, i=1,...,4 are arbitrary diagonal matrices. As an application, the paper proposes new accurate algorithms for computing the (H,K)-SVD and (H1,K)-SVD of S.
Accurate thermoelastic tensor and acoustic velocities of NaCl
Marcondes, Michel L.; Shukla, Gaurav; Silveira, Pedro da; Wentzcovitch, Renata M.
2015-12-15
Despite the importance of thermoelastic properties of minerals in geology and geophysics, their measurement at high pressures and temperatures are still challenging. Thus, ab initio calculations are an essential tool for predicting these properties at extreme conditions. Owing to the approximate description of the exchange-correlation energy, approximations used in calculations of vibrational effects, and numerical/methodological approximations, these methods produce systematic deviations. Hybrid schemes combining experimental data and theoretical results have emerged as a way to reconcile available information and offer more reliable predictions at experimentally inaccessible thermodynamics conditions. Here we introduce a method to improve the calculated thermoelastic tensor by using highly accurate thermal equation of state (EoS). The corrective scheme is general, applicable to crystalline solids with any symmetry, and can produce accurate results at conditions where experimental data may not exist. We apply it to rock-salt-type NaCl, a material whose structural properties have been challenging to describe accurately by standard ab initio methods and whose acoustic/seismic properties are important for the gas and oil industry.
A unique approach to accurately measure thickness in thick multilayers.
Shi, Bing; Hiller, Jon M; Liu, Yuzi; Liu, Chian; Qian, Jun; Gades, Lisa; Wieczorek, Michael J; Marander, Albert T; Maser, Jorg; Assoufid, Lahsen
2012-05-01
X-ray optics called multilayer Laue lenses (MLLs) provide a promising path to focusing hard X-rays with high focusing efficiency at a resolution between 5 nm and 20 nm. MLLs consist of thousands of depth-graded thin layers. The thickness of each layer obeys the linear zone plate law. X-ray beamline tests have been performed on magnetron sputter-deposited WSi(2)/Si MLLs at the Advanced Photon Source/Center for Nanoscale Materials 26-ID nanoprobe beamline. However, it is still very challenging to accurately grow each layer at the designed thickness during deposition; errors introduced during thickness measurements of thousands of layers lead to inaccurate MLL structures. Here, a new metrology approach that can accurately measure thickness by introducing regular marks on the cross section of thousands of layers using a focused ion beam is reported. This new measurement method is compared with a previous method. More accurate results are obtained using the new measurement approach. PMID:22514179
Soluble high molecular weight polyimide resins
NASA Technical Reports Server (NTRS)
Jones, R. J.; Lubowitz, H. R.
1970-01-01
High molecular weight polyimide resins have greater than 20 percent /by weight/ solubility in polar organic solvents. They permit fabrication into films, fibers, coatings, reinforced composite, and adhesive product forms. Characterization properties for one typical polyimide resin are given.
Ultrahigh molecular weight aromatic siloxane polymers
NASA Technical Reports Server (NTRS)
Ludwick, L. M.
1982-01-01
The condensation of a diol with a silane in toluene yields a silphenylene-siloxane polymer. The reaction of stiochiometric amounts of the diol and silane produced products with molecular weights in the range 2.0 - 6.0 x 10 to the 5th power. The molecular weight of the product was greatly increased by a multistep technique. The methodology for synthesis of high molecular weight polymers using a two step procedure was refined. Polymers with weight average molecular weights in excess of 1.0 x 10 to the 6th power produced by this method. Two more reactive silanes, bis(pyrrolidinyl)dimethylsilane and bis(gamma butyrolactam)dimethylsilane, are compared with the dimethyleminodimethylsilane in ability to advance the molecular weight of the prepolymer. The polymers produced are characterized by intrinsic viscosity in tetrahydrofuran. Weight and number average molecular weights and polydispersity are determined by gel permeation chromatography.
Weight-Control Information Network (WIN)
... Feature: Reducing Childhood Obesity The Weight-control Information Network (WIN) Past Issues / Spring - Summer 2010 Table of ... here are tips from the Weight-control Information Network (WIN), an information service of the National Institute ...
Weight-loss surgery and children
... and blood pressure Fewer sleep problems In the United States, weight loss operations have been used with success ... is not yet approved for teenagers in the United States. All weight loss operations can be performed through ...
Parents: Stay Mum on Daughter's Weight
... news/fullstory_159269.html Parents: Stay Mum on Daughter's Weight Girls who hear comments on size more ... be cautious about what they say to their daughters about their weight, new research says. The study ...
Nagging Your Kids about Weight Might Backfire
... medlineplus.gov/news/fullstory_158443.html Nagging Your Kids About Weight Might Backfire Children added pounds if ... regardless of whether they are or not -- those kids are likely to gain weight, a new study ...
Physical Activity for a Healthy Weight
... Physical Activity Overweight & Obesity Healthy Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Physical Activity for a ... Physical Activity Overweight & Obesity Healthy Weight Breastfeeding Micronutrient Malnutrition State and Local Programs Language: English Español (Spanish) ...
The Molecular Weight Distribution of Polymer Samples
ERIC Educational Resources Information Center
Horta, Arturo; Pastoriza, M. Alejandra
2007-01-01
Various methods for the determination of the molecular weight distribution (MWD) of different polymer samples are presented. The study shows that the molecular weight averages and distribution of a polymerization completely depend on the characteristics of the reaction itself.
Energy Expenditure During Walking with Hand Weights.
ERIC Educational Resources Information Center
Makalous, Susan L.; And Others
1988-01-01
A study of 11 obese adults who exercised with hand weights concludes that using the weights increases the energy demands of walking but only slightly. Research and results are presented and analyzed. (JL)
Code of Federal Regulations, 2010 CFR
2010-04-01
... must be able to prove: (i) By written certification, the weight of the APU; and (ii) By demonstration...) Certification of the weight of the APU must be available to law enforcement officers if the vehicle is found...
Weight, gender, and snack appeal.
Havermans, Remco C; Giesen, Janneke C A H; Houben, Katrijn; Jansen, Anita
2011-04-01
In this study, we hypothesized that overweight/obese persons have an exaggerated approach tendency toward high calorie foods. Testing this hypothesis, a stimulus response compatibility (SRC) task was used to assess approach-avoidance tendencies toward food in both overweight/obese participants (n=42), and normal weight controls (n=46). The SRC task is a reaction time task measuring how fast one approaches and avoids pictures of food and non-foods according to given instructions. It was found that overweight/obese men are slower at avoiding particularly high calorie snack foods. But this does not appear to be the case for overweight/obese women who showed nearly as fast avoidance as approach toward the high calorie food cues. It is concluded that overweight/obese women, rather than men, are ambivalent toward high calorie foods, which is the likely result of high dietary restraint. PMID:21385642
Light-weight ceramic insulation
NASA Technical Reports Server (NTRS)
Hsu, Ming-Ta S. (Inventor); Chen, Timothy S. (Inventor)
2002-01-01
Ultra-high temperature, light-weight, ceramic insulation such as ceramic tile is obtained by pyrolyzing a siloxane gel derived from the reaction of at least one organo dialkoxy silane and at least one tetralkoxy silane in an acid or base liquid medium. The reaction mixture of the tetra- and dialkoxy silanes may contain also an effective amount of a mono- or trialkoxy silane to obtain the siloxane gel. The siloxane gel is dried at ambient pressures to form a siloxane ceramic precursor without significant shrinkage. The siloxane ceramic precursor is subsequently pyrolyzed, in an inert atmosphere, to form the black ceramic insulation comprising atoms of silicon, carbon and oxygen. The ceramic insulation, can be characterized as a porous, uniform ceramic tile resistant to oxidation at temperatures ranging as high as 1700.degree. C. and is particularly useful as lightweight tiles for spacecraft and other high-temperature insulation applications.
Multipliers in weighted Sobolev spaces
NASA Astrophysics Data System (ADS)
Kusainova, L. K.
2005-08-01
Let X_1 and X_2 be a pair of Banach spaces of functions in \\Omega\\subset{\\mathbb R}^n. A multiplier from X_1 into X_2 is a function \\gamma on \\Omega such that \\gamma X_1=\\{\\gamma f,\\ f\\in X_1\\}\\subset X_2. By the norm \\Vert\\gamma\\Vert=\\Vert\\gamma\\Vert _{M(X_1\\to X_2)} one means the norm of the operator T(u)=\\gamma u, u\\in X_1. Conditions ensuring that a function \\gamma belongs to the multiplier classes M(W_1\\to W_2) and M(W\\to L) are found, where W and L are Sobolev and Lebesgue weighted spaces, respectively. Estimates of the norms of multipliers free from capacity characteristics are found. Special local maximal operators are introduced and significantly used.
'Doctor, how can I lose weight?'.
Bright-See, E
1983-11-01
Millions of Canadians are trying to lose weight. According to the Metropolitan Life Insurance Company's recently released height and weight tables, some of them don't need to lose weight from a health standpoint. For those who would benefit from weight loss, a good program includes a balanced, low fat, high fiber diet; exercise; behavior modification and moral support. Few of the popular books and self-help groups offer all these essential components. PMID:21283478
Gestational weight gain among Hispanic women.
Sangi-Haghpeykar, Haleh; Lam, Kim; Raine, Susan P
2014-01-01
To describe gestational weight gain among Hispanic women and to examine psychological, social, and cultural contexts affecting weight gain. A total of 282 Hispanic women were surveyed post-partum before leaving the hospital. Women were queried about their prepregnancy weight and weight gained during pregnancy. Adequacy of gestational weight gain was based on guidelines set by the Institute of Medicine in 2009. Independent risk factors for excessive or insufficient weight gain were examined by logistic regression. Most women were unmarried (59 %), with a mean age of 28.4 ± 6.6 years and an average weight gain of 27.9 ± 13.3 lbs. Approximately 45 % of women had gained too much, 32 % too little, and only 24 % had an adequate amount of weight gain. The mean birth weight was 7.3, 7.9, and 6.8 lbs among the adequate, excessive, and insufficient weight gain groups. Among women who exercised before pregnancy, two-thirds continued to do so during pregnancy; the mean gestational weight gain of those who continued was lower than those who stopped (26.8 vs. 31.4 lbs, p = 0.04). Independent risk factors for excessive weight gain were being unmarried, U.S. born, higher prepregnancy body mass index, and having indifferent or negative views about weight gain. Independent risk factors for insufficient weight gain were low levels of support and late initiation of prenatal care. Depression, stress, and a woman's or her partner's happiness regarding pregnancy were unrelated to weight gain. The results of this study can be used by prenatal programs to identify Hispanic women at risk for excessive or insufficient gestational weight gain. PMID:23456347
Choosing Small Weights For Multiple Error Detection
NASA Astrophysics Data System (ADS)
Brent, Richard P.; Luk, Franklin T.; Anfinson, Cynthia J.
1989-05-01
The weighted checksum technique has been demonstrated to be effective in multiple error detection. It has been shown that, in order to guarantee error detection, the chosen weight vectors must satisfy some very specific properties about linear independence. Previous weight generating methods that fulfill the independence criteria have problems with numerical overflow. We present a new scheme that generates weight vectors to meet the requirements about independence and to avoid the difficulties with overflow.
Prediction of the weight of Alaskan pollock using image analysis.
Balaban, Murat O; Chombeau, Melanie; Cırban, Dilşat; Gümüş, Bahar
2010-10-01
Determining the size and quality attributes of fish by machine vision is gaining acceptance and increasing use in the seafood industry. Objectivity, speed, and record keeping are advantages in using this method. The objective of this work was to develop the mathematical correlations to predict the weight of whole Alaskan Pollock (Theragra chalcogramma) based on its view area from a camera. One hundred and sixty whole Pollock were obtained fresh, within 2 d after catch from a Kodiak, Alaska, processing plant. The fish were first weighed, then placed in a light box equipped with a Nikon D200 digital camera. A reference square of known surface area was placed by the fish. The obtained image was analyzed to calculate the view area of each fish. The following equations were used to fit the view area (X) compared with weight (Y) data: linear, power, and 2nd-order polynomial. The power fit (Y = A · X(B)) gave the highest R(2) for the fit (0.99). The effect of fins and tail on the accuracy of the weight prediction using view area were evaluated. Removing fins and tails did not improve prediction accuracy. Machine vision can accurately predict the weight of whole Pollock. Practical Application: The weight of Alaskan Pollock can be predicted automatically by taking the image of the fish and using it in one of the correlations developed in this study. The removal of the fins or the fins and the tail did not increase the prediction accuracy of the method. Therefore, intact fish images should be used. PMID:21535495
Hybrid weighted essentially non-oscillatory schemes with different indicators
NASA Astrophysics Data System (ADS)
Li, Gang; Qiu, Jianxian
2010-10-01
A key idea in finite difference weighted essentially non-oscillatory (WENO) schemes is a combination of lower order fluxes to obtain a higher order approximation. The choice of the weight to each candidate stencil, which is a nonlinear function of the grid values, is crucial to the success of WENO schemes. For the system case, WENO schemes are based on local characteristic decompositions and flux splitting to avoid spurious oscillation. But the cost of computation of nonlinear weights and local characteristic decompositions is very high. In this paper, we investigate hybrid schemes of WENO schemes with high order up-wind linear schemes using different discontinuity indicators and explore the possibility in avoiding the local characteristic decompositions and the nonlinear weights for part of the procedure, hence reducing the cost but still maintaining non-oscillatory properties for problems with strong shocks. The idea is to identify discontinuity by an discontinuity indicator, then reconstruct numerical flux by WENO approximation in discontinuous regions and up-wind linear approximation in smooth regions. These indicators are mainly based on the troubled-cell indicators for discontinuous Galerkin (DG) method which are listed in the paper by Qiu and Shu (J. Qiu, C.-W. Shu, A comparison of troubled-cell indicators for Runge-Kutta discontinuous Galerkin methods using weighted essentially non-oscillatory limiters, SIAM Journal of Scientific Computing 27 (2005) 995-1013). The emphasis of the paper is on comparison of the performance of hybrid scheme using different indicators, with an objective of obtaining efficient and reliable indicators to obtain better performance of hybrid scheme to save computational cost. Detail numerical studies in one- and two-dimensional cases are performed, addressing the issues of efficiency (less CPU time and more accurate numerical solution), non-oscillatory property.
Exercise and activity for weight loss
An active lifestyle and exercise routine, along with eating healthy foods, is the best way to lose weight. ... Calories used in exercise > calories eaten = weight loss. This means that to lose weight, the number of calories you burn by exercising needs ...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Weight loss. 4.112... DISABILITIES Disability Ratings The Digestive System § 4.112 Weight loss. For purposes of evaluating conditions in § 4.114, the term “substantial weight loss” means a loss of greater than 20 percent of...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Weight loss. 4.112... DISABILITIES Disability Ratings The Digestive System § 4.112 Weight loss. For purposes of evaluating conditions in § 4.114, the term “substantial weight loss” means a loss of greater than 20 percent of...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Weight loss. 4.112... DISABILITIES Disability Ratings The Digestive System § 4.112 Weight loss. For purposes of evaluating conditions in § 4.114, the term “substantial weight loss” means a loss of greater than 20 percent of...
Measuring Bearing Wear Via Weight Loss
NASA Technical Reports Server (NTRS)
Keba, John E.; Moore, Richard S.
1989-01-01
Wear in critical parts of bearings measured via amounts of weight lost during use. Technique applicable in general to bearings made of nonporous materials. Weight-loss measurements easier, faster, more precise, and less likely to damage measured parts. Weight-loss measurements performed in clean rooms and under constraint of extreme cleanliness for compatability with liquid oxygen.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Weight loss. 4.112... DISABILITIES Disability Ratings The Digestive System § 4.112 Weight loss. For purposes of evaluating conditions in § 4.114, the term “substantial weight loss” means a loss of greater than 20 percent of...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Empty weight. 31.16 Section 31.16... STANDARDS: MANNED FREE BALLOONS Flight Requirements § 31.16 Empty weight. The empty weight must be determined by weighing the balloon with installed equipment but without lifting gas or heater fuel....
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Empty weight. 31.16 Section 31.16... STANDARDS: MANNED FREE BALLOONS Flight Requirements § 31.16 Empty weight. The empty weight must be determined by weighing the balloon with installed equipment but without lifting gas or heater fuel....
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Empty weight. 31.16 Section 31.16... STANDARDS: MANNED FREE BALLOONS Flight Requirements § 31.16 Empty weight. The empty weight must be determined by weighing the balloon with installed equipment but without lifting gas or heater fuel....
Is Weight Training Safe during Pregnancy?
ERIC Educational Resources Information Center
Work, Janis A.
1989-01-01
Examines the opinions of several experts on the safety of weight training during pregnancy, noting that no definitive research on weight training alone has been done. Experts agree that low-intensity weight training probably poses no harm for mother or fetus; exercise programs should be individualized. (SM)