#### Sample records for 85th percentile speeds

1. Quantile regression provides a fuller analysis of speed data.

PubMed

Hewson, Paul

2008-03-01

Considerable interest already exists in terms of assessing percentiles of speed distributions, for example monitoring the 85th percentile speed is a common feature of the investigation of many road safety interventions. However, unlike the mean, where t-tests and ANOVA can be used to provide evidence of a statistically significant change, inference on these percentiles is much less common. This paper examines the potential role of quantile regression for modelling the 85th percentile, or any other quantile. Given that crash risk may increase disproportionately with increasing relative speed, it may be argued these quantiles are of more interest than the conditional mean. In common with the more usual linear regression, quantile regression admits a simple test as to whether the 85th percentile speed has changed following an intervention in an analogous way to using the t-test to determine if the mean speed has changed by considering the significance of parameters fitted to a design matrix. Having briefly outlined the technique and briefly examined an application with a widely published dataset concerning speed measurements taken around the introduction of signs in Cambridgeshire, this paper will demonstrate the potential for quantile regression modelling by examining recent data from Northamptonshire collected in conjunction with a "community speed watch" programme. Freely available software is used to fit these models and it is hoped that the potential benefits of using quantile regression methods when examining and analysing speed data are demonstrated. PMID:18329400

2. Tutorial: Calculating Percentile Rank and Percentile Norms Using SPSS

ERIC Educational Resources Information Center

Baumgartner, Ted A.

2009-01-01

Practitioners can benefit from using norms, but they often have to develop their own percentile rank and percentile norms. This article is a tutorial on how to quickly and easily calculate percentile rank and percentile norms using SPSS, and this information is presented for a data set. Some issues in calculating percentile rank and percentile…

3. Managing speed at school and playground zones.

PubMed

Kattan, Lina; Tay, Richard; Acharjee, Shanti

2011-09-01

Since speeding is one of the major causes of frequent and severe traffic accidents around school and playground areas, many jurisdictions have reduced the speed limits in these areas to protect children who may be at risk. This paper investigated the speed compliance, mean speed and 85th percentile speed at selected school and playground zones in the City of Calgary in Alberta. Our results showed that the mean speed was lower and the rate of compliance was higher in the school zone compared to the playground zone, 2 lane roads relative to 4 lane roads, roads with fencing, traffic control devices and the presence of speed display device or children, and zones that were longer (> 200 m). Accordingly, this study provided recommendations to improve the effectiveness of school and playground zone speed limits. PMID:21658518

4. Pay as You Speed, ISA with incentive for not speeding: results and interpretation of speed data.

PubMed

Lahrmann, Harry; Agerholm, Niels; Tradisauskas, Nerius; Berthelsen, Kasper K; Harms, Lisbeth

2012-09-01

To simulate a market introduction of Intelligent Speed Adaptation (ISA) and to study the effect of a Pay as You Speed (PAYS) concept, a field trial with 153 drivers was conducted during 2007-2009. The participants drove under PAYS conditions for a shorter or a longer period. The PAYS concept consisted of informative ISA linked with economic incentive for not speeding, measured through automatic count of penalty points whenever the speed limit was exceeded. The full incentive was set to 30% of a participant's insurance premium. The participants were exposed to different treatments, with and without incentive crossed with informative ISA present or absent. The results showed that ISA is an efficient tool for reducing speeding particularly on rural roads. The analysis of speed data demonstrated that the proportion of distance driven above the speed where the ISA equipment responded (PDA) was a sensitive measure for reflecting the effect of ISA, whereas mean free flow speed and the 85th percentile speed, were less sensitive to ISA effects. The PDA increased a little over time but still remained at a low level; however, when ISA was turned off, the participants' speeding relapsed to the baseline level. Both informative ISA and incentive ISA reduced the PDA, but there was no statistically significant interaction. Informative reduced it more than the incentive. PMID:22664664

5. Effects on speed and safety of point-to-point speed enforcement systems: evaluation on the urban motorway A56 Tangenziale di Napoli.

PubMed

Montella, Alfonso; Imbriani, Lella Liana; Marzano, Vittorio; Mauriello, Filomena

2015-02-01

In this paper, we evaluated the effects on speed and safety of the point-to-point (P2P) speed enforcement system activated on the urban motorway A56 in Italy. The P2P speed enforcement is a relatively new approach to traffic law enforcement that involves the calculation of the average speed over a section. To evaluate the speed effects, we performed a before-after analysis of speed data investigating also effects on non-compliance to speed limits. To evaluate the safety effects, we carried out an empirical Bayes observational before-and-after study. The P2P system led to very positive effects on both speed and safety. As far as the effects on the section average travel speeds, the system yielded to a reduction in the mean speed, the 85th percentile speed, the standard deviation of speed, and the proportion of drivers exceeding the speed limits, exceeding the speed limits more than 10km/h, and exceeding the speed limits more than 20km/h. The best results were the decrease of the speed variability and the reduction of the excessive speeding behaviour. The decrease in the standard deviation of speed was 26% while the proportion of light and heavy vehicles exceeding the speed limits more than 20km/h was reduced respectively by 84 and 77%. As far as the safety effects, the P2P system yielded to a 32% reduction in the total crashes, with a lower 95% confidence limit of the estimate equal to 22%. The greatest crash reductions were in rainy weather (57%), on wet pavement (51%), on curves (49%), for single vehicle crashes (44%), and for injury crashes (37%). It is noteworthy that the system produced a statistically significant reduction of 21% in total crashes also in the part of the motorway where it was not activated, thus generating a significant spillover effect. The investigation of the effects of the P2P system on speed and safety over time allowed to develop crash modification functions where the relationship between crash modification factors and speed parameters

6. A Comparison of Three Conditional Growth Percentile Methods: Student Growth Percentiles, Percentile Rank Residuals, and a Matching Method

ERIC Educational Resources Information Center

Wyse, Adam E.; Seo, Dong Gi

2014-01-01

This article provides a brief overview and comparison of three conditional growth percentile methods; student growth percentiles, percentile rank residuals, and a nonparametric matching method. These approaches seek to describe student growth in terms of the relative percentile ranking of a student in relationship to students that had the same…

7. Waist Circumferences of Chilean Students: Comparison of the CDC-2012 Standard and Proposed Percentile Curves

PubMed Central

Gómez-Campos, Rossana; Lee Andruske, Cinthya; Hespanhol, Jefferson; Sulla Torres, Jose; Arruda, Miguel; Luarte-Rocha, Cristian; Cossio-Bolaños, Marco Antonio

2015-01-01

The measurement of waist circumference (WC) is considered to be an important means to control overweight and obesity in children and adolescents. The objectives of the study were to (a) compare the WC measurements of Chilean students with the international CDC-2012 standard and other international standards, and (b) propose a specific measurement value for the WC of Chilean students based on age and sex. A total of 3892 students (6 to 18 years old) were assessed. Weight, height, body mass index (BMI), and WC were measured. WC was compared with the CDC-2012 international standard. Percentiles were constructed based on the LMS method. Chilean males had a greater WC during infancy. Subsequently, in late adolescence, males showed values lower than those of the international standards. Chilean females demonstrated values similar to the standards until the age of 12. Subsequently, females showed lower values. The 85th and 95th percentiles were adopted as cutoff points for evaluating overweight and obesity based on age and sex. The WC of Chilean students differs from the CDC-2012 curves. The regional norms proposed are a means to identify children and adolescents with a high risk of suffering from overweight and obesity disorders. PMID:26184250

8. Waist Circumferences of Chilean Students: Comparison of the CDC-2012 Standard and Proposed Percentile Curves.

PubMed

Gómez-Campos, Rossana; Andruske, Cinthya Lee; Hespanhol, Jefferson; Torres, Jose Sulla; Arruda, Miguel; Luarte-Rocha, Cristian; Cossio-Bolaños, Marco Antonio

2015-07-01

The measurement of waist circumference (WC) is considered to be an important means to control overweight and obesity in children and adolescents. The objectives of the study were to (a) compare the WC measurements of Chilean students with the international CDC-2012 standard and other international standards, and (b) propose a specific measurement value for the WC of Chilean students based on age and sex. A total of 3892 students (6 to 18 years old) were assessed. Weight, height, body mass index (BMI), and WC were measured. WC was compared with the CDC-2012 international standard. Percentiles were constructed based on the LMS method. Chilean males had a greater WC during infancy. Subsequently, in late adolescence, males showed values lower than those of the international standards. Chilean females demonstrated values similar to the standards until the age of 12. Subsequently, females showed lower values. The 85th and 95th percentiles were adopted as cutoff points for evaluating overweight and obesity based on age and sex. The WC of Chilean students differs from the CDC-2012 curves. The regional norms proposed are a means to identify children and adolescents with a high risk of suffering from overweight and obesity disorders. PMID:26184250

9. An Activity for Learning to Find Percentiles

ERIC Educational Resources Information Center

Cox, Richard G.

2016-01-01

This classroom activity is designed to help students practice calculating percentiles. The approach of the activity involves physical sorting and full classroom participation in each calculation. The design encourages a more engaged approach than simply having students make a calculation with numbers on a paper.

10. Evaluating the safety impact of increased speed limits on rural highways in British Columbia.

PubMed

Sayed, Tarek; Sacchi, Emanuele

2016-10-01

Maximum speed limits are usually set to inform drivers of the highest speed that it is safe and appropriate for ideal traffic, road and weather conditions. Many previous studies were conducted to investigate the relationship between changed speed limits and safety. The results of these studies generally show that relaxing speed limits can negatively affect safety, especially with regard to fatal and injury crashes. Despite these results, several road jurisdictions in North America continue to raise the maximum speed limits. In 2013, the British Columbia Ministry of Transportation and Infrastructure initiated a speed limits review. The review found that the 85th percentile speed on many highway segments was 10km/h higher than corresponding posted speed limits and 1300km of rural provincial highway segments were recommended for higher speed limits. Most of the highway segments had 10km/h speed limit increase with a small section having 20km/h speed limit increase. As speed limit changes can have a substantial impact on safety, the main objective of this study is to estimate the effect of the increased speed limits on crash occurrence. A before-after evaluation was undertaken with the full Bayesian technique. Overall, the evaluation showed that changed speed limits led to a statistically significant increase in fatal-plus-injury (severe) crashes of 11.1%. A crash modification function that includes changes in the treatment effect over time showed that the initial increase of the first post-implementation period may slightly decrease over time. PMID:27447060

11. Empirical analysis of gross vehicle weight and free flow speed and consideration on its relation with differential speed limit.

PubMed

Saifizul, Ahmad Abdullah; Yamanaka, Hideo; Karim, Mohamed Rehan

2011-05-01

Most highly motorized countries in the world have implemented different speed limits for light weight and heavy weight vehicles. The heavy vehicle speed limit is usually chosen to be lower than that of passenger cars due to the difficulty for the drivers to safely maneuver the heavy vehicle at high speed and greater impact during a crash. However, in many cases, the speed limit for heavy vehicle is set by only considering the vehicle size or category, mostly due to simplicity in enforcement. In this study, traffic and vehicular data for all vehicle types were collected using a weigh-in-motion system installed at Federal Route 54 in Malaysia. The first finding from the data showed that the weight variation for each vehicle category is considerable. Therefore, the effect of gross vehicle weight (GVW) and category of heavy vehicle on free flow speed and their interaction were analyzed using statistical techniques. Empirical analysis results showed that statistically for each type of heavy vehicle, there was a significant relationship between free flow speed of a heavy vehicle and GVW. Specifically, the results suggest that the mean and variance of free flow speed decrease with an increase GVW by the amount unrelated to size and shape for all GVW range. Then, based on the 85th percentile principle, the study proposed a new concept for setting the speed limit for heavy vehicle by incorporating GVW where a different speed limit is imposed to the heavy vehicle, not only based on vehicle classification, but also according to its GVW. PMID:21376903

12. Evaluation of the effects of school zone signs and markings on speed reduction: a driving simulator study.

PubMed

Zhao, Xiaohua; Li, Jiahui; Ma, Jianming; Rong, Jian

2016-01-01

Traffic control devices are one of the most significant factors affecting driving behavior. In China, there is a lack of installation guidelines or standards for traffic control devices in school zones. In addition, little research has been done to examine the effects of traffic control devices on driving behavior. Few guidelines have been established for implementing traffic control devices in school zones in China. This research conducted a driving simulator experiment to assess the effects of school zone signs and markings for two different types of schools. The efficiency of these traffic control devices was evaluated using four variables derived from the driving simulation, including average speed, relative speed difference, standard deviation of acceleration, and 85th percentile speed. Results showed that traffic control devices such as the Flashing Beacon and School Crossing Ahead Warning Assembly, the Reduce Speed and School Crossing Warning Assembly, and the School Crossing Ahead Pavement Markings were recommended for school zones adjacent to a major multilane roadway, which is characterized by a median strip, high traffic volume, high-speed traffic and the presence of pedestrian crossing signals. The School Crossing Ahead Pavement Markings were recommended for school zones on a minor two-lane roadway, which is characterized by low traffic volume, low speed, and no pedestrian crossing signals. PMID:27390630

13. Alternative Statistical Frameworks for Student Growth Percentile Estimation

ERIC Educational Resources Information Center

Lockwood, J. R.; Castellano, Katherine E.

2015-01-01

This article suggests two alternative statistical approaches for estimating student growth percentiles (SGP). The first is to estimate percentile ranks of current test scores conditional on past test scores directly, by modeling the conditional cumulative distribution functions, rather than indirectly through quantile regressions. This would…

14. Percentile curves for skinfold thickness for Canadian children and youth

PubMed Central

Ashley-Martin, Jillian; Maguire, Bryan; Hamilton, David C.

2016-01-01

Background. Skinfold thickness (SFT) measurements are a reliable and feasible method for assessing body fat in children but their use and interpretation is hindered by the scarcity of reference values in representative populations of children. The objective of the present study was to develop age- and sex-specific percentile curves for five SFT measures (biceps, triceps, subscapular, suprailiac, medial calf) in a representative population of Canadian children and youth. Methods. We analyzed data from 3,938 children and adolescents between 6 and 19 years of age who participated in the Canadian Health Measures Survey cycles 1 (2007/2009) and 2 (2009/2011). Standardized procedures were used to measure SFT. Age- and sex-specific centiles for SFT were calculated using the GAMLSS method. Results. Percentile curves were materially different in absolute value and shape for boys and girls. Percentile girls in girls steadily increased with age whereas percentile curves in boys were characterized by a pubertal centered peak. Conclusions. The current study has presented for the first time percentile curves for five SFT measures in a representative sample of Canadian children and youth. PMID:27547554

15. Percentile curves for skinfold thickness for Canadian children and youth.

PubMed

Kuhle, Stefan; Ashley-Martin, Jillian; Maguire, Bryan; Hamilton, David C

2016-01-01

Background. Skinfold thickness (SFT) measurements are a reliable and feasible method for assessing body fat in children but their use and interpretation is hindered by the scarcity of reference values in representative populations of children. The objective of the present study was to develop age- and sex-specific percentile curves for five SFT measures (biceps, triceps, subscapular, suprailiac, medial calf) in a representative population of Canadian children and youth. Methods. We analyzed data from 3,938 children and adolescents between 6 and 19 years of age who participated in the Canadian Health Measures Survey cycles 1 (2007/2009) and 2 (2009/2011). Standardized procedures were used to measure SFT. Age- and sex-specific centiles for SFT were calculated using the GAMLSS method. Results. Percentile curves were materially different in absolute value and shape for boys and girls. Percentile girls in girls steadily increased with age whereas percentile curves in boys were characterized by a pubertal centered peak. Conclusions. The current study has presented for the first time percentile curves for five SFT measures in a representative sample of Canadian children and youth. PMID:27547554

16. Percentile Curves for Anthropometric Measures for Canadian Children and Youth

PubMed Central

Kuhle, Stefan; Maguire, Bryan; Ata, Nicole; Hamilton, David

2015-01-01

Body mass index (BMI) is commonly used to assess a child's weight status but it does not provide information about the distribution of body fat. Since the disease risks associated with obesity are related to the amount and distribution of body fat, measures that assess visceral or subcutaneous fat, such as waist circumference (WC), waist-to-height ratio (WHtR), or skinfolds thickness may be more suitable. The objective of this study was to develop percentile curves for BMI, WC, WHtR, and sum of 5 skinfolds (SF5) in a representative sample of Canadian children and youth. The analysis used data from 4115 children and adolescents between 6 and 19 years of age that participated in the Canadian Health Measures Survey Cycles 1 (2007/2009) and 2 (2009/2011). BMI, WC, WHtR, and SF5 were measured using standardized procedures. Age- and sex-specific centiles were calculated using the LMS method and the percentiles that intersect the adult cutpoints for BMI, WC, and WHtR at age 18 years were determined. Percentile curves for all measures showed an upward shift compared to curves from the pre-obesity epidemic era. The adult cutoffs for overweight and obesity corresponded to the 72nd and 91st percentile, respectively, for both sexes. The current study has presented for the first time percentile curves for BMI, WC, WHtR, and SF5 in a representative sample of Canadian children and youth. The percentile curves presented are meant to be descriptive rather than prescriptive as associations with cardiovascular disease markers or outcomes were not assessed. PMID:26176769

17. Examining the Reliability of Student Growth Percentiles Using Multidimensional IRT

ERIC Educational Resources Information Center

Monroe, Scott; Cai, Li

2015-01-01

Student growth percentiles (SGPs, Betebenner, 2009) are used to locate a student's current score in a conditional distribution based on the student's past scores. Currently, following Betebenner (2009), quantile regression (QR) is most often used operationally to estimate the SGPs. Alternatively, multidimensional item response theory (MIRT) may…

18. Urinary iodine percentile ranges in the United States

PubMed Central

Soldin, Offie Porat; Soldin, Steven J.; Pezzullo, John C.

2013-01-01

Background The status of iodine nutrition of a population can be determined by measurement of urinary iodine concentrations since it is thought to indicate dietary iodine intake. Normally, these results are compared to population-based criteria, since there are no reference ranges for urinary iodine. Objective To determine the percentile ranges for urinary iodide (UI) concentrations in normal individuals in the United States. Materials and methods The third National Health and Nutrition Examination Survey (NHANES III) (1988–1994) database of the civilian, non-institutionalized, iodine-sufficient US population was used. The 2.5th to 97.5th percentile ranges for urinary iodine and for urinary iodine per gram creatinine ratio (UI/Cr) (μg/g) were calculated for females and males, 6–89 years of age, each stratified by age groups. Results and conclusions We calculated the percentile ranges for urinary iodine. After exclusions of subjects with goiter or thyroid disease, the study sample included 21,530 subjects; 10,439 males and 11,091 females. For women of childbearing age (14–44 years), urinary iodine concentration 2.5th to 97.5th percentiles are 1.8–65 μg/dl or 36–539 μg/g creatinine. For pregnant women, the ranges are 4.2–55 μg/dl or 33–535 μg/g creatinine. PMID:12559616

19. Punching Wholes into Parts, or Beating the Percentile Averages.

ERIC Educational Resources Information Center

Carwile, Nancy R.

1990-01-01

Presents a facetious, ingenious resolution to the percentile dilemma concerning above- and below-average test scores. If schools enrolled the same number of pigs as students and tested both groups, the pigs would fill up the bottom half and all children would rank in the top 50 percent. However, some wrinkles need to be ironed out! (MLH)

20. Establishing percentiles for junior tennis players based on physical fitness testing results.

PubMed

Roetert, E P; Piorkowski, P A; Woods, R B; Brown, S W

1995-01-01

An important aspect of this study was the establishment of a data base. A broad data base allows for data on certain parameters to be greatly expanded and will also enhance the use and interpretation of statistical methods. A longitudinal study of these variables may also assist in monitoring the players' progress over a period of time, and can provide a useful supplement to subjective coaching appraisals. The means and standard deviation for each test were calculated according to the USTA age and gender groups, that is, 12s, 14s, and 16s for each separate gender. Additionally, the mean and standard deviations for the ages, heights, and weights of each grouping were also calculated. Once the means and standard deviations were calculated, percentile tables were developed for each of the USTA groupings (by age and gender). The percentiles for each USTA test are presented in Appendix 1. A percentile is defined as the point on the distribution below which a given percentage of the scores is found. Percentiles can provide a norm-referenced interpretation of an individual score within a distribution that often consists of scores from a comparable group of individuals. Using the USTA protocol, players and coaches now have a set of normative data by which individual player's fitness scores may be compared with participants of the USTA Area Training Centers (See appendix 1). From the test results, coaches and players can determine which fitness areas need to be improved for athletes on an individual basis. Specific training programs can then be designed based on an athlete's fitness testing results. Proper interpretation of the USTA fitness testing data base results can lead to an easy way to determine the relative position of a given fitness score in the distribution, recognizing weaker areas for the purpose of injury prevention and performance enhancement. Each player can be given a profile detailing their percentile rank relative to other area training center

1. Percentile growth charts for biomedical studies using a porcine model.

PubMed

Corson, A M; Laws, J; Laws, A; Litten, J C; Lean, I J; Clarke, L

2008-12-01

Increasing rates of obesity and heart disease are compromising quality of life for a growing number of people. There is much research linking adult disease with the growth and development both in utero and during the first year of life. The pig is an ideal model for studying the origins of developmental programming. The objective of this paper was to construct percentile growth curves for the pig for use in biomedical studies. The body weight (BW) of pigs was recorded from birth to 150 days of age and their crown-to-rump length was measured over the neonatal period to enable the ponderal index (PI; kg/m3) to be calculated. Data were normalised and percentile curves were constructed using Cole's lambda-mu-sigma (LMS) method for BW and PI. The construction of these percentile charts for use in biomedical research will allow a more detailed and precise tracking of growth and development of individual pigs under experimental conditions. PMID:22444086

2. Physical Fitness Percentiles of German Children Aged 9–12 Years: Findings from a Longitudinal Study

PubMed Central

Golle, Kathleen; Muehlbauer, Thomas; Wick, Ditmar; Granacher, Urs

2015-01-01

Background Generating percentile values is helpful for the identification of children with specific fitness characteristics (i.e., low or high fitness level) to set appropriate fitness goals (i.e., fitness/health promotion and/or long-term youth athlete development). Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9–12 years and to compute sex- and age-specific percentile values. Methods Two-hundred and forty children (88 girls, 152 boys) participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i.e., speed), the 1-kg ball push test, the triple hop test (i.e., upper- and lower- extremity muscular power), the stand-and-reach test (i.e., flexibility), the star run test (i.e., agility), and the 9-min run test (i.e., endurance). Age- and sex-specific percentile values (i.e., P10 to P90) were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance) age- and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen’s d). Results Significant main effects of Age were detected for all physical fitness tests (d = 0.40–1.34), whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55), flexibility (d = 0.81), agility (d = 0.44), and endurance (d = 0.32) only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36), flexibility (d = 0.61), and agility (d = 0.27) in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear) improvements were observed for upper-extremity muscular power (boys: 10–11 yrs; girls: 9–11 yrs), agility (boys: 9–10 yrs; girls: 9–11 yrs), and endurance (boys: 9–10 yrs; girls: 9–10 yrs). Tabulated percentiles for the 9-min run test

3. Binorm-a fortran subroutine to calculate the percentiles of a standardized binormal distribution

USGS Publications Warehouse

McCammon, R.B.

1977-01-01

BINORM is a FORTRAN subroutine for calculating the percentiles of a standardized binormal distribution. By using a linear transformation, the percentiles of a binormal distribution can be obtained. The percentiles of a binormal distribution are useful for plotting purposes, for establishing confidence intervals, and for sampling from a mixed population that consists of two normal distributions. ?? 1977.

4. Development of a Three-Dimensional Finite Element Chest Model for the 5(th) Percentile Female.

PubMed

Kimpara, Hideyuki; Lee, Jong B; Yang, King H; King, Albert I; Iwamoto, Masami; Watanabe, Isao; Miki, Kazuo

2005-11-01

Several three-dimensional (3D) finite element (FE) models of the human body have been developed to elucidate injury mechanisms due to automotive crashes. However, these models are mainly focused on 50(th) percentile male. As a first step towards a better understanding of injury biomechanics in the small female, a 3D FE model of a 5(th) percentile female human chest (FEM-5F) has been developed and validated against experimental data obtained from two sets of frontal impact, one set of lateral impact, two sets of oblique impact and a series of ballistic impacts. Two previous FE models, a small female Total HUman Model for Safety (THUMS-AF05) occupant version 1.0Beta (Kimpara et al. 2002) and the Wayne State University Human Thoracic Model (WSUHTM, Wang 1995 and Shah et al. 2001) were integrated and modified for this model development. The model incorporated not only geometrical gender differences, such as location of the internal organs and structure of the bony skeleton, but also the biomechanical differences of the ribs due to gender. It includes a detailed description of the sternum, ribs, costal cartilage, thoracic spine, skin, superficial muscles, intercostal muscles, heart, lung, diaphragm, major blood vessels and simplified abdominal internal organs and has been validated against a series of six cadaveric experiments on the small female reported by Nahum et al. (1970), Kroell et al. (1974), Viano (1989), Talantikite et al. (1998) and Wilhelm (2003). Results predicted by the model were well-matched to these experimental data for a range of impact speeds and impactor masses. More research is needed in order to increase the accuracy of predicting rib fractures so that the mechanisms responsible for small female injury can be more clearly defined. PMID:17096277

5. Colorado Growth Model--Brief Report: Student Growth Percentiles and FRL Status. Accountability & Data Analysis Unit

ERIC Educational Resources Information Center

2013-01-01

This report examines the relationship between socioeconomic status, as defined by a free-and-reduced lunch proxy variable, and student growth percentiles by elementary, middle, and high school grade levels for math, reading, and writing. Comparisons were made between median growth percentiles for each educational level by free and reduced lunch…

6. Development of a percentile based three-dimensional model of the buttocks in computer system

Wang, Lijing; He, Xueli; Li, Hongpeng

2016-04-01

There are diverse products related to human buttocks, which need to be designed, manufactured and evaluated with 3D buttock model. The 3D buttock model used in present research field is just simple approximate model similar to human buttocks. The 3D buttock percentile model is highly desired in the ergonomics design and evaluation for these products. So far, there is no research on the percentile sizing system of human 3D buttock model. So the purpose of this paper is to develop a new method for building three-dimensional buttock percentile model in computer system. After scanning the 3D shape of buttocks, the cloud data of 3D points is imported into the reverse engineering software (Geomagic) for the reconstructing of the buttock surface model. Five characteristic dimensions of the buttock are measured through mark-points after models being imported into engineering software CATIA. A series of space points are obtained by the intersecting of the cutting slices and 3D buttock surface model, and then are ordered based on the sequence number of the horizontal and vertical slices. The 1st, 5th, 50th, 95th, 99th percentile values of the five dimensions and the spatial coordinate values of the space points are obtained, and used to reconstruct percentile buttock models. This research proposes a establishing method of percentile sizing system of buttock 3D model based on the percentile values of the ischial tuberosities diameter, the distances from margin to ischial tuberosity and the space coordinates value of coordinate points, for establishing the Nth percentile 3D buttock model and every special buttock types model. The proposed method also serves as a useful guidance for the other 3D percentile models establishment for other part in human body with characteristic points.

7. Development of a percentile based three-dimensional model of the buttocks in computer system

Wang, Lijing; He, Xueli; Li, Hongpeng

2016-05-01

There are diverse products related to human buttocks, which need to be designed, manufactured and evaluated with 3D buttock model. The 3D buttock model used in present research field is just simple approximate model similar to human buttocks. The 3D buttock percentile model is highly desired in the ergonomics design and evaluation for these products. So far, there is no research on the percentile sizing system of human 3D buttock model. So the purpose of this paper is to develop a new method for building three-dimensional buttock percentile model in computer system. After scanning the 3D shape of buttocks, the cloud data of 3D points is imported into the reverse engineering software (Geomagic) for the reconstructing of the buttock surface model. Five characteristic dimensions of the buttock are measured through mark-points after models being imported into engineering software CATIA. A series of space points are obtained by the intersecting of the cutting slices and 3D buttock surface model, and then are ordered based on the sequence number of the horizontal and vertical slices. The 1st, 5th, 50th, 95th, 99th percentile values of the five dimensions and the spatial coordinate values of the space points are obtained, and used to reconstruct percentile buttock models. This research proposes a establishing method of percentile sizing system of buttock 3D model based on the percentile values of the ischial tuberosities diameter, the distances from margin to ischial tuberosity and the space coordinates value of coordinate points, for establishing the Nth percentile 3D buttock model and every special buttock types model. The proposed method also serves as a useful guidance for the other 3D percentile models establishment for other part in human body with characteristic points.

8. Hypothesis Testing of Population Percentiles via the Wald Test with Bootstrap Variance Estimates

PubMed Central

Johnson, William D.; Romer, Jacob E.

2016-01-01

Testing the equality of percentiles (quantiles) between populations is an effective method for robust, nonparametric comparison, especially when the distributions are asymmetric or irregularly shaped. Unlike global nonparametric tests for homogeneity such as the Kolmogorv-Smirnov test, testing the equality of a set of percentiles (i.e., a percentile profile) yields an estimate of the location and extent of the differences between the populations along the entire domain. The Wald test using bootstrap estimates of variance of the order statistics provides a unified method for hypothesis testing of functions of the population percentiles. Simulation studies are conducted to show performance of the method under various scenarios and to give suggestions on its use. Several examples are given to illustrate some useful applications to real data. PMID:27034909

9. Shaping in the 21st century: Moving percentile schedules into applied settings

PubMed Central

Galbicka, Gregory

1994-01-01

The present paper provides a primer on percentile reinforcement schedules, which have been used for two decades to study response differentiation and shaping in the laboratory. Arranged in applied settings, percentile procedures could be used to specify response criteria, standardizing treatment across subjects, trainers, and times to provide a more consistent training environment while maintaining the sensitivity to the individual's repertoire that is the hallmark of shaping. Percentile schedules are also valuable tools in analyzing the variables of which responding is a function, both inside and outside the laboratory. Finally, by formalizing the rules of shaping, percentile schedules provide a useful heuristic of the processes involved in shaping behavior, even for those situations that may not easily permit their implementation. As such, they may help further sensitize trainers and researchers alike to variables of critical importance in behavior change. ImagesFigure 6 PMID:16795849

10. Comparison of daily percentiles of streamflow and rainfall to investigate stream aquifer connectivity

Brodie, Ross S.; Hostetler, Stephen; Slatter, Emily

2008-01-01

SummaryA frequency analysis approach was used to investigate the hydraulic connectivity between streams and aquifers, by comparing daily percentiles of streamflow and rainfall. Three Australian streams were examined - a dominantly gaining stream (Wilsons River, NSW), a dominantly gaining stream modified by significant water extraction (Ovens River, Victoria) and a dominantly losing stream (Mooki River, NSW). For the gaining stream examples, a lag is observed between the seasonal peak in the low-flow percentile curves and the seasonal peak in the daily rainfall percentile curve. Cross-correlation was used to calculate the time-shift that provides the best fit between the streamflow and rainfall percentile curves. There is a good correlation ( r2 > 0.8) between the reference rainfall percentile curve and the shifted streamflow percentile curves for gaining streams. The lags evident between the rainfall and streamflow percentile curves represent the processes of first replenishing catchment storages (such as soil moisture and groundwater) and subsequent release to the stream. This is largely a function of catchment hydrogeology as well as climate, notably the magnitude and regularity of rainfall events. Catchment size is not a controlling factor. Analysis of these lags provides insights into the dynamics of groundwater recharge, storage and release. Changes in the lag times over the flow percentiles can reflect changes in the dominant catchment storage contributing to streamflow. For the Wilsons River, the contribution from a groundwater system with longer flow paths increases at lower flow percentiles. This can be critical when protecting minimum streamflows, as near-stream groundwater flow may not be the only determining factor. The impact of water extraction can be recognised in this analysis. For the Ovens River, streamflow deficits relative to the rainfall percentile curve correspond to the summer period of high irrigation demand. Such a deficit was also observed

11. Analysis of extreme top event frequency percentiles based on fast probability integration

SciTech Connect

1993-10-01

In risk assessments, a primary objective is to determine the frequency with which a collection of initiating and basic events, E{sub e} leads to some undesired top event, T. Uncertainties in the occurrence rates, x{sub t}, assigned to the initiating and basic events cause uncertainty in the top event frequency, z{sub T}. The quantification of the uncertainty in z{sub T} is an essential part of risk assessment called uncertainty analysis. In the past, it has been difficult to evaluate the extreme percentiles of output variables like z{sub T}. Analytic methods such as the method of moments do not provide estimates of output percentiles and the Monte Carlo (MC) method can be used to estimate extreme output percentiles only by resorting to large sample sizes. A promising altemative to these methods is the fast probability integration (FPI) methods. These methods approximate the integrals of multi-variate functions, representing percentiles of interest, without recourse to multi-dimensional numerical integration. FPI methods give precise results and have been demonstrated to be more efficient than MC methods for estimating extreme output percentiles. FPI allows the analyst to choose extreme percentiles of interest and perform sensitivity analyses in those regions. Such analyses can provide valuable insights as to the events driving the top event frequency response in extreme probability regions. In this paper, FPI methods are adapted a) to precisely estimate extreme top event frequency percentiles and b) to allow the quantification of sensitivity measures at these extreme percentiles. In addition, the relative precision and efficiency of alternative methods for treating lognormally distributed inputs is investigated. The methodology is applied to the top event frequency expression for the dominant accident sequence from a risk assessment of Grand Gulf nuclear power plant.

12. CONFERENCES AND SYMPOSIA Commemoration of the 85th birthday of S I Syrovatskii(Scientific session of the Physical Sciences Division of the Russian Academy of Sciences, 26 May 2010)

2010-12-01

A scientific session of the Physical Sciences Division, Russian Academy of Sciences (RAS), was held on 26 May 2010 at the conference hall of the Lebedev Physical Institute, RAS. The session was devoted to the 85th birthday of S I Syrovatskii. The program announced on the web page of the RAS Physical Sciences Division (www.gpad.ac.ru) contained the following reports: (1) Zelenyi L M (Space Research Institute, RAS, Moscow) "Current sheets and reconnection in the geomagnetic tail"; (2) Frank A G (Prokhorov General Physics Institute, RAS, Moscow) "Dynamics of current sheets as the cause of flare events in magnetized plasmas"; (3) Kuznetsov V D (Pushkov Institute of Terrestrial Magnetism, the Ionosphere, and Radio Wave Propagation, RAS, Troitsk, Moscow region) "Space research on the Sun"; (4) Somov B V (Shternberg Astronomical Institute, Lomonosov Moscow State University, Moscow) "Strong shock waves and extreme plasma states"; (5) Zybin K P (Lebedev Physical Institute, RAS, Moscow) "Structure functions for developed turbulence"; (6) Ptuskin V S (Pushkov Institute of Terrestrial Magnetism, the Ionosphere, and Radio Wave Propagation, RAS, Troitsk, Moscow region) "The origin of cosmic rays." Papers based on reports 1-4 and 6 are published in what follows. • Metastability of current sheets, L M Zelenyi, A V Artemyev, Kh V Malova, A A Petrukovich, R Nakamura Physics-Uspekhi, 2010, Volume 53, Number 9, Pages 933-941 • Dynamics of current sheets underlying flare-type events in magnetized plasmas, A G Frank Physics-Uspekhi, 2010, Volume 53, Number 9, Pages 941-947 • Space research of the Sun, V D Kuznetsov Physics-Uspekhi, 2010, Volume 53, Number 9, Pages 947-954 • Magnetic reconnection in solar flares, B V Somov Physics-Uspekhi, 2010, Volume 53, Number 9, Pages 954-958 • The origin of cosmic rays, V S Ptuskin Physics-Uspekhi, 2010, Volume 53, Number 9, Pages 958-961

13. NIH peer review percentile scores are poorly predictive of grant productivity

PubMed Central

Fang, Ferric C; Bowen, Anthony; Casadevall, Arturo

2016-01-01

Peer review is widely used to assess grant applications so that the highest ranked applications can be funded. A number of studies have questioned the ability of peer review panels to predict the productivity of applications, but a recent analysis of grants funded by the National Institutes of Health (NIH) in the US found that the percentile scores awarded by peer review panels correlated with productivity as measured by citations of grant-supported publications. Here, based on a re-analysis of these data for the 102,740 funded grants with percentile scores of 20 or better, we report that these percentile scores are a poor discriminator of productivity. This underscores the limitations of peer review as a means of assessing grant applications in an era when typical success rates are often as low as about 10%. DOI: http://dx.doi.org/10.7554/eLife.13323.001 PMID:26880623

14. Estimation of a monotone percentile residual life function under random censorship.

PubMed

Franco-Pereira, Alba M; de Uña-Álvarez, Jacobo

2013-01-01

In this paper, we introduce a new estimator of a percentile residual life function with censored data under a monotonicity constraint. Specifically, it is assumed that the percentile residual life is a decreasing function. This assumption is useful when estimating the percentile residual life of units, which degenerate with age. We establish a law of the iterated logarithm for the proposed estimator, and its n-equivalence to the unrestricted estimator. The asymptotic normal distribution of the estimator and its strong approximation to a Gaussian process are also established. We investigate the finite sample performance of the monotone estimator in an extensive simulation study. Finally, data from a clinical trial in primary biliary cirrhosis of the liver are analyzed with the proposed methods. One of the conclusions of our work is that the restricted estimator may be much more efficient than the unrestricted one. PMID:23225621

15. NIH peer review percentile scores are poorly predictive of grant productivity.

PubMed

Fang, Ferric C; Bowen, Anthony; Casadevall, Arturo

2016-01-01

Peer review is widely used to assess grant applications so that the highest ranked applications can be funded. A number of studies have questioned the ability of peer review panels to predict the productivity of applications, but a recent analysis of grants funded by the National Institutes of Health (NIH) in the US found that the percentile scores awarded by peer review panels correlated with productivity as measured by citations of grant-supported publications. Here, based on a re-analysis of these data for the 102,740 funded grants with percentile scores of 20 or better, we report that these percentile scores are a poor discriminator of productivity. This underscores the limitations of peer review as a means of assessing grant applications in an era when typical success rates are often as low as about 10%. PMID:26880623

16. Problems with Percentiles: Student Growth Scores in New York's Teacher Evaluation System

ERIC Educational Resources Information Center

Patrick, Drew

2016-01-01

New York State has used the Growth Model for Educator Evaluation ratings since the 2011-2012 school year. Since that time, student growth percentiles have been used as the basis for teacher and principal ratings. While a great deal has been written about the use of student test scores to measures educator effectiveness, less attention has been…

17. Percentile Norms for the AAHPER Cooperative Physical Education Tests. Research Report.

ERIC Educational Resources Information Center

Moodie, Allan G.

Percentile scores for Vancouver students in grades 9, 10, 11 and 12 on the AAHPER Cooperative Physical Education Tests are presented. Two of the six forms of the tests were used in these administrations. Every form consists of 60 multiple-choice questions to be completed in 40 minutes. A single score, based on the number of questions answered…

18. Can Percentiles Replace Raw Scores in the Statistical Analysis of Test Data?

ERIC Educational Resources Information Center

Zimmerman, Donald W.; Zumbo, Bruno D.

2005-01-01

Educational and psychological testing textbooks typically warn of the inappropriateness of performing arithmetic operations and statistical analysis on percentiles instead of raw scores. This seems inconsistent with the well-established finding that transforming scores to ranks and using nonparametric methods often improves the validity and power…

19. A Comparison of Growth Percentile and Value-Added Models of Teacher Performance. Working Paper #39

ERIC Educational Resources Information Center

Guarino, Cassandra M.; Reckase, Mark D.; Stacy, Brian W.; Wooldridge, Jeffrey M.

2014-01-01

School districts and state departments of education frequently must choose between a variety of methods to estimating teacher quality. This paper examines under what circumstances the decision between estimators of teacher quality is important. We examine estimates derived from student growth percentile measures and estimates derived from commonly…

20. Birthweight percentiles for twin birth neonates by gestational age in China.

PubMed

Zhang, Bin; Cao, Zhongqiang; Zhang, Yiming; Yao, Cong; Xiong, Chao; Zhang, Yaqi; Wang, Youjie; Zhou, Aifen

2016-01-01

Localized birthweight references for gestational ages serve as an essential tool in accurate evaluation of atypical birth outcomes. Such references for twin births are currently not available in China. The aim of this study was to construct up-to-data sex specific birth weight references by gestational ages for twin births in China. We conducted a population-based analysis on the data of 22,507 eligible living twin infants with births dated between 8/01/2006 and 8/31/2015 from all 95 hospitals within the Wuhan area. Gestational ages in complete weeks were determined using a combination of last-menstrual-period based (LMP) estimation and ultrasound examination. Smoothed percentile curves were created by the Lambda Mu Sigma (LMS) method. Reference of the 3(rd), 10(th), 25(th), 50(th), 75(th), 90(th), 97(th) percentiles birth weight by sex and gestational age were made using 11,861 male and 10,646 female twin newborns with gestational age 26-42 weeks. Separate birthweight percentiles curves for male and female twins were constructed. In summary, our study firstly presents percentile curves of birthweight by gestational age for Chinese twin neonates. Further research is required for the validation and implementation of twin birthweight curves into clinical practice. PMID:27506479

1. Age-specific percentile-based reference curve of serum procalcitonin concentrations in Japanese preterm infants.

PubMed

Fukuzumi, Noriko; Osawa, Kayo; Sato, Itsuko; Iwatani, Sota; Ishino, Ruri; Hayashi, Nobuhide; Iijima, Kazumoto; Saegusa, Jun; Morioka, Ichiro

2016-01-01

Procalcitonin (PCT) levels are elevated early after birth in newborn infants; however, the physiological features and reference of serum PCT concentrations have not been fully studied in preterm infants. The aims of the current study were to establish an age-specific percentile-based reference curve of serum PCT concentrations in preterm infants and determine the features. The PCT concentration peaked in infants at 1 day old and decreased thereafter. At 1 day old, serum PCT concentrations in preterm infants <34 weeks' gestational age were higher than those in late preterm infants between 34 and 36 weeks' gestational age or term infants ≥37 weeks' gestational age. Although the 50-percentile value in late preterm and term infants reached the adult normal level (0.1 ng/mL) at 5 days old, it did not in preterm infants. It took 9 weeks for preterm infants to reach it. Serum PCT concentrations at onset in late-onset infected preterm infants were over the 95-percentile value. We showed that the physiological feature in preterm infants was significantly different from that in late preterm infants, even in those <37 weeks' gestational age. To detect late-onset bacterial infection and sepsis, an age-specific percentile-based reference curve may be useful in preterm infants. PMID:27033746

2. Age-specific percentile-based reference curve of serum procalcitonin concentrations in Japanese preterm infants

PubMed Central

Fukuzumi, Noriko; Osawa, Kayo; Sato, Itsuko; Iwatani, Sota; Ishino, Ruri; Hayashi, Nobuhide; Iijima, Kazumoto; Saegusa, Jun; Morioka, Ichiro

2016-01-01

Procalcitonin (PCT) levels are elevated early after birth in newborn infants; however, the physiological features and reference of serum PCT concentrations have not been fully studied in preterm infants. The aims of the current study were to establish an age-specific percentile-based reference curve of serum PCT concentrations in preterm infants and determine the features. The PCT concentration peaked in infants at 1 day old and decreased thereafter. At 1 day old, serum PCT concentrations in preterm infants <34 weeks’ gestational age were higher than those in late preterm infants between 34 and 36 weeks’ gestational age or term infants ≥37 weeks’ gestational age. Although the 50-percentile value in late preterm and term infants reached the adult normal level (0.1 ng/mL) at 5 days old, it did not in preterm infants. It took 9 weeks for preterm infants to reach it. Serum PCT concentrations at onset in late-onset infected preterm infants were over the 95-percentile value. We showed that the physiological feature in preterm infants was significantly different from that in late preterm infants, even in those <37 weeks’ gestational age. To detect late-onset bacterial infection and sepsis, an age-specific percentile-based reference curve may be useful in preterm infants. PMID:27033746

3. AGE AND GENDER SPECIFIC BMI PERCENTILES ARE LIMITED FOR TRACKING THE CHILDHOOD OBESITY EPIDEMIC

Technology Transfer Automated Retrieval System (TEKTRAN)

Purpose: To evaluate pediatric nutrition and physical activity interventions a reliable and feasible way of tracking change in body status is needed. Historically, body mass index (BMI) has been used in adults. BMI percentiles or Z scores, which are theoretically age and gender adjusted, have been...

4. Student Growth Percentiles Based on MIRT: Implications of Calibrated Projection. CRESST Report 842

ERIC Educational Resources Information Center

Monroe, Scott; Cai, Li; Choi, Kilchan

2014-01-01

This research concerns a new proposal for calculating student growth percentiles (SGP, Betebenner, 2009). In Betebenner (2009), quantile regression (QR) is used to estimate the SGPs. However, measurement error in the score estimates, which always exists in practice, leads to bias in the QR-­based estimates (Shang, 2012). One way to address this…

5. Risk for nonalcoholic fatty liver disease in Hispanic Youth with BMI > or = 95th percentile

Technology Transfer Automated Retrieval System (TEKTRAN)

To characterize children at risk for nonalcoholic fatty liver disease (NAFLD) and to explore possible mechanisms underlying the development of NAFLD in Hispanic youth with a body mass index > or =95th percentile. Hispanic nonoverweight (n = 475) and overweight (n = 517) children, ages 4 to 19 y, wer...

6. User Guide for the 2014-15 Teacher Median Student Growth Percentile Report

ERIC Educational Resources Information Center

New Jersey Department of Education, 2016

2016-01-01

On March 22, 2016, the New Jersey Department of Education ("the Department") published a broadcast memo sharing secure district access to 2014-15 median Student Growth Percentile (mSGP) data for all qualifying teachers. These data describe student growth from the last school year, and comprise 10% of qualifying teachers' 2014-15…

7. Birthweight percentiles for twin birth neonates by gestational age in China

PubMed Central

Zhang, Bin; Cao, Zhongqiang; Zhang, Yiming; Yao, Cong; Xiong, Chao; Zhang, Yaqi; Wang, Youjie; Zhou, Aifen

2016-01-01

Localized birthweight references for gestational ages serve as an essential tool in accurate evaluation of atypical birth outcomes. Such references for twin births are currently not available in China. The aim of this study was to construct up-to-data sex specific birth weight references by gestational ages for twin births in China. We conducted a population-based analysis on the data of 22,507 eligible living twin infants with births dated between 8/01/2006 and 8/31/2015 from all 95 hospitals within the Wuhan area. Gestational ages in complete weeks were determined using a combination of last-menstrual-period based (LMP) estimation and ultrasound examination. Smoothed percentile curves were created by the Lambda Mu Sigma (LMS) method. Reference of the 3rd, 10th, 25th, 50th, 75th, 90th, 97th percentiles birth weight by sex and gestational age were made using 11,861 male and 10,646 female twin newborns with gestational age 26–42 weeks. Separate birthweight percentiles curves for male and female twins were constructed. In summary, our study firstly presents percentile curves of birthweight by gestational age for Chinese twin neonates. Further research is required for the validation and implementation of twin birthweight curves into clinical practice. PMID:27506479

8. Using Percentile Schedules to Increase Eye Contact in Children with Fragile X Syndrome

ERIC Educational Resources Information Center

Hall, Scott S.; Maynes, Natalee P.; Reiss, Allan L.

2009-01-01

Aversion to eye contact is a common behavior of individuals diagnosed with Fragile X syndrome (FXS); however, no studies to date have attempted to increase eye-contact duration in these individuals. In this study, we employed a percentile reinforcement schedule with and without overcorrection to shape eye-contact duration of 6 boys with FXS.…

9. Statewide Analysis of the Drainage-Area Ratio Method for 34 Streamflow Percentile Ranges in Texas

USGS Publications Warehouse

Asquith, William H.; Roussel, Meghan C.; Vrabel, Joseph

2006-01-01

The drainage-area ratio method commonly is used to estimate streamflow for sites where no streamflow data are available using data from one or more nearby streamflow-gaging stations. The method is intuitive and straightforward to implement and is in widespread use by analysts and managers of surface-water resources. The method equates the ratio of streamflow at two stream locations to the ratio of the respective drainage areas. In practice, unity often is assumed as the exponent on the drainage-area ratio, and unity also is assumed as a multiplicative bias correction. These two assumptions are evaluated in this investigation through statewide analysis of daily mean streamflow in Texas. The investigation was made by the U.S. Geological Survey in cooperation with the Texas Commission on Environmental Quality. More than 7.8 million values of daily mean streamflow for 712 U.S. Geological Survey streamflow-gaging stations in Texas were analyzed. To account for the influence of streamflow probability on the drainage-area ratio method, 34 percentile ranges were considered. The 34 ranges are the 4 quartiles (0-25, 25-50, 50-75, and 75-100 percent), the 5 intervals of the lower tail of the streamflow distribution (0-1, 1-2, 2-3, 3-4, and 4-5 percent), the 20 quintiles of the 4 quartiles (0-5, 5-10, 10-15, 15-20, 20-25, 25-30, 30-35, 35-40, 40-45, 45-50, 50-55, 55-60, 60-65, 65-70, 70-75, 75-80, 80-85, 85-90, 90-95, and 95-100 percent), and the 5 intervals of the upper tail of the streamflow distribution (95-96, 96-97, 97-98, 98-99 and 99-100 percent). For each of the 253,116 (712X711/2) unique pairings of stations and for each of the 34 percentile ranges, the concurrent daily mean streamflow values available for the two stations provided for station-pair application of the drainage-area ratio method. For each station pair, specific statistical summarization (median, mean, and standard deviation) of both the exponent and bias-correction components of the drainage-area ratio

10. Relationships between walking and percentiles of adiposity inolder and younger men

SciTech Connect

Williams, Paul T.

2005-06-01

To assess the relationship of weekly walking distance to percentiles of adiposity in elders (age {ge} 75 years), seniors (55 {le} age <75 years), middle-age men (35 {le} age <55 years), and younger men (18 {le} age <35 years old). Cross-sectional analyses of baseline questionnaires from 7,082 male participants of the National Walkers Health Study. The walkers BMIs were inversely and significantly associated with walking distance (kg/m{sup 2} per km/wk) in elders (slope {+-} SE: -0.032 {+-} 0.008), seniors (-0.045 {+-} 0.005), and middle-aged men (-0.037 {+-} 0.007), as were their waist circumferences (-0.091 {+-} 0.025, -0.045 {+-} 0.005, and -0.091 {+-} 0.015 cm per km/wk, respectively), and these slopes remained significant when adjusted statistically for reported weekly servings of meat, fish, fruit, and alcohol. The declines in BMI associated with walking distance were greater at the higher than lower percentiles of the BMI distribution. Specifically, compared to the decline at the 10th BMI percentile, the decline in BMI at the 90th percentile was 5.1-fold greater in elders, 5.9-fold greater in seniors, and 6.7-fold greater in middle-age men. The declines in waist circumference associated with walking distance were also greater among men with broader waistlines. Exercise-induced weight loss (or self-selection) causes an inverse relationship between adiposity and walking distance in men 35 and older that is substantially greater among fatter men.

11. Trend estimates of AERONET-observed and model-simulated AOT percentiles between 1993 and 2013

Yoon, Jongmin; Pozzer, Andrea; Chang, Dong Yeong; Lelieveld, Jos

2016-04-01

Recent Aerosol Optical thickness (AOT) trend studies used monthly or annual arithmetic means that discard details of the generally right-skewed AOT distributions. Potentially, such results can be biased by extreme values (including outliers). This study additionally uses percentiles (i.e., the lowest 5%, 25%, 50%, 75% and 95% of the monthly cumulative distributions fitted to Aerosol Robotic Network (AERONET)-observed and ECHAM/MESSy Atmospheric Chemistry (EMAC)-model simulated AOTs) that are less affected by outliers caused by measurement error, cloud contamination and occasional extreme aerosol events. Since the limited statistical representativeness of monthly percentiles and means can lead to bias, this study adopts the number of observations as a weighting factor, which improves the statistical robustness of trend estimates. By analyzing the aerosol composition of AERONET-observed and EMAC-simulated AOTs in selected regions of interest, we distinguish the dominant aerosol types and investigate the causes of regional AOT trends. The simulated and observed trends are generally consistent with a high correlation coefficient (R = 0.89) and small bias (slope±2σ = 0.75 ± 0.19). A significant decrease in EMAC-decomposed AOTs by water-soluble compounds and black carbon is found over the USA and the EU due to environmental regulation. In particular, a clear reversal in the AERONET AOT trend percentiles is found over the USA, probably related to the AOT diurnal cycle and the frequency of wildfires.

12. Estimated monthly percentile discharges at ungaged sites in the Upper Yellowstone River Basin in Montana

USGS Publications Warehouse

Parrett, Charles; Hull, J.A.

1986-01-01

Once-monthly streamflow measurements were used to estimate selected percentile discharges on flow-duration curves of monthly mean discharge for 40 ungaged stream sites in the upper Yellowstone River basin in Montana. The estimation technique was a modification of the concurrent-discharge method previously described and used by H.C. Riggs to estimate annual mean discharge. The modified technique is based on the relationship of various mean seasonal discharges to the required discharges on the flow-duration curves. The mean seasonal discharges are estimated from the monthly streamflow measurements, and the percentile discharges are calculated from regression equations. The regression equations, developed from streamflow record at nine gaging stations, indicated a significant log-linear relationship between mean seasonal discharge and various percentile discharges. The technique was tested at two discontinued streamflow-gaging stations; the differences between estimated monthly discharges and those determined from the discharge record ranged from -31 to +27 percent at one site and from -14 to +85 percent at the other. The estimates at one site were unbiased, and the estimates at the other site were consistently larger than the recorded values. Based on the test results, the probable average error of the technique was + or - 30 percent for the 21 sites measured during the first year of the program and + or - 50 percent for the 19 sites measured during the second year. (USGS)

13. Percentile Distributions of Birth Weight according to Gestational Ages in Korea (2010-2012)

PubMed Central

2016-01-01

The Pediatric Growth Chart (2007) is used as a standard reference to evaluate weight and height percentiles of Korean children and adolescents. Although several previous studies provided a useful reference range of newborn birth weight (BW) by gestational age (GA), the BW reference analyzed by sex and plurality is not currently available. Therefore, we aimed to establish a national reference range of neonatal BW percentiles considering GA, sex, and plurality of newborns in Korea. The raw data of all newborns (470,171 in 2010, 471,265 in 2011, and 484,550 in 2012) were analyzed. Using the Korean Statistical Information Service data (2010–2012), smoothed percentile curves (3rd–97th) by GA were created using the lambda-mu-sigma method after exclusion and the data were distinguished by all live births, singleton births, and multiple births. In the entire cohort, male newborns were heavier than female newborns and singletons were heavier than twins. As GA increased, the difference in BW between singleton and multiples increased. Compared to the previous data published 10 years ago in Korea, the BW of newborns 22–23 gestational weeks old was increased, whereas that of others was smaller. Other countries' data were also compared and showed differences in BW of both singleton and multiple newborns. We expect this updated data to be utilized as a reference to improve clinical assessments of newborn growth. PMID:27247504

14. Percentile Distributions of Birth Weight according to Gestational Ages in Korea (2010-2012).

PubMed

Lee, Jin Kyoung; Jang, Hye Lim; Kang, Byung Ho; Lee, Kyung-Suk; Choi, Yong-Sung; Shim, Kye Shik; Lim, Jae Woo; Bae, Chong-Woo; Chung, Sung-Hoon

2016-06-01

The Pediatric Growth Chart (2007) is used as a standard reference to evaluate weight and height percentiles of Korean children and adolescents. Although several previous studies provided a useful reference range of newborn birth weight (BW) by gestational age (GA), the BW reference analyzed by sex and plurality is not currently available. Therefore, we aimed to establish a national reference range of neonatal BW percentiles considering GA, sex, and plurality of newborns in Korea. The raw data of all newborns (470,171 in 2010, 471,265 in 2011, and 484,550 in 2012) were analyzed. Using the Korean Statistical Information Service data (2010-2012), smoothed percentile curves (3(rd)-97(th)) by GA were created using the lambda-mu-sigma method after exclusion and the data were distinguished by all live births, singleton births, and multiple births. In the entire cohort, male newborns were heavier than female newborns and singletons were heavier than twins. As GA increased, the difference in BW between singleton and multiples increased. Compared to the previous data published 10 years ago in Korea, the BW of newborns 22-23 gestational weeks old was increased, whereas that of others was smaller. Other countries' data were also compared and showed differences in BW of both singleton and multiple newborns. We expect this updated data to be utilized as a reference to improve clinical assessments of newborn growth. PMID:27247504

15. A COMPARISON OF STUDENTS SCORING ABOVE THE EIGHTIETH PERCENTILE OR BELOW THE TWENTIETH PERCENTILE ON EITHER THE SCHOOL AND COLLEGE ABILITY TEST OR THE WATSON-GLASER TEST OF CRITICAL THINKING.

ERIC Educational Resources Information Center

CURRY, JOHN

IN ORDER TO ESTABLISH THE FEASIBILITY OF A CUT-OFF SCORE FOR ENTRANCE INTO TEACHER EDUCATION PROGRAMS AT NORTH TEXAS STATE UNIVERSITY, SCORES OF 1,346 STUDENTS WHO EITHER PLACED ABOVE THE 80TH PERCENTILE (N-672) OR BELOW THE 20TH PERCENTILE (N-674) ON EITHER THE SCHOOL AND COLLEGE ABILITY TEST OR THE WATSON-GLASER TEST OF CRITICAL THINKING WERE…

16. Percentile-based Empirical Distribution Function Estimates for Performance Evaluation of Healthcare Providers

PubMed Central

Paddock, Susan M.; Louis, Thomas A.

2010-01-01

Summary Hierarchical models are widely-used to characterize the performance of individual healthcare providers. However, little attention has been devoted to system-wide performance evaluations, the goals of which include identifying extreme (e.g., top 10%) provider performance and developing statistical benchmarks to define high-quality care. Obtaining optimal estimates of these quantities requires estimating the empirical distribution function (EDF) of provider-specific parameters that generate the dataset under consideration. However, the difficulty of obtaining uncertainty bounds for a square-error loss minimizing EDF estimate has hindered its use in system-wide performance evaluations. We therefore develop and study a percentile-based EDF estimate for univariate provider-specific parameters. We compute order statistics of samples drawn from the posterior distribution of provider-specific parameters to obtain relevant uncertainty assessments of an EDF estimate and its features, such as thresholds and percentiles. We apply our method to data from the Medicare End Stage Renal Disease (ESRD) Program, a health insurance program for people with irreversible kidney failure. We highlight the risk of misclassifying providers as exceptionally good or poor performers when uncertainty in statistical benchmark estimates is ignored. Given the high stakes of performance evaluations, statistical benchmarks should be accompanied by precision estimates. PMID:21918583

17. Ensemble hydrological prediction of streamflow percentile at ungauged basins in Pakistan

2015-06-01

Streamflow records with sufficient spatial and temporal coverage at the site of interest are usually scarce in Pakistan. As an alternative, various regional methods have been frequently adopted to derive hydrological information, which in essence attempt to transfer hydrological information from gauged to ungauged catchments. In this study, a new concept of ensemble hydrological prediction (EHP) was introduced which is an improved regional method for hydrological prediction at ungauged sites. It was mainly based on the performance weights (triple-connection weights (TCW)) derived from Nash Sutcliffe efficiency (NSE) and hydrological variable (here percentiles) calculated from three traditional regional transfer methods (RTMs) with suitable modification (i.e., three-step drainage area ratio (DAR) method, inverse distance weighting (IDW) method, and three-step regional regression analysis (RRA)). The overall results indicated that the proposed EHP method was robust for estimating hydrological percentiles at ungauged sites as compared to traditional individual RTMs. The comparative study based on NSE, percent bias (PBIAS) and the relative error (RE) as performance criteria resulted that the EHP is a constructive alternative for hydrological prediction of ungauged basins.

18. State disparities in time trends of adolescent body mass index percentile and weight-related behaviors in the United States.

PubMed

Taber, Daniel R; Stevens, June; Poole, Charles; Maciejewski, Matthew L; Evenson, Kelly R; Ward, Dianne S

2012-02-01

Evidence is conflicting as to whether youth obesity prevalence has reached a plateau in the United States overall. Trends vary by state, and experts recommend exploring whether trends in weight-related behaviors are associated with changes in weight status trends. Thus, our objective was to estimate between-state variation in time trends of adolescent body mass index (BMI) percentile and weight-related behaviors from 2001 to 2007. A time series design combined cross-sectional Youth Risk Behavior Survey data from 272,044 adolescents in 29 states from 2001 to 2007. Self-reported height, weight, sports participation, physical education, television viewing, and daily consumption of 100% fruit juice, milk, and fruits and vegetables were collected. Linear mixed models estimated state variance in time trends of behaviors and BMI percentile. Across states, BMI percentile trends were consistent despite differences in behavioral trends. Boys experienced a modest linear increase in BMI percentile (ß = 0.18, 95% CI: 0.07, 0.30); girls experienced a non-linear increase, as the rate of increase declined over time from 1.02 units in 2001-2002 (95% CI: 0.68, 1.36) to 0.23 units in 2006-2007 (95% CI: -0.09, 0.56). States in which BMI percentile decreased experienced a greater decrease in TV viewing than states where BMI percentile increased. Otherwise, states with disparate BMI percentile trends did not differ with respect to behaviors. Future research should explore the role of other behaviors (e.g., soda consumption), measurement units (e.g., portion size), and societal trends (e.g., urban sprawl) on state and national adiposity trends. PMID:21773818

19. Percentile Ranking and Citation Impact of a Large Cohort of NHLBI-funded Cardiovascular R01 Grants

PubMed Central

Danthi, Narasimhan; Wu, Colin O.; Shi, Peibei; Lauer, Michael

2014-01-01

Rationale Funding decisions for cardiovascular R01 grant applications at NHLBI largely hinge on percentile rankings. It is not known whether this approach enables the highest impact science. Objective To conduct an observational analysis of percentile rankings and bibliometric outcomes for a contemporary set of funded NHLBI cardiovascular R01 grants. Methods and results We identified 1492 investigator-initiated de novo R01 grant applications that were funded between 2001 and 2008, and followed their progress for linked publications and citations to those publications. Our co-primary endpoints were citations received per million dollars of funding, citations obtained within 2-years of publication, and 2-year citations for each grant’s maximally cited paper. In 7654 grant-years of funding that generated $3004 million of total NIH awards, the portfolio yielded 16,793 publications that appeared between 2001 and 2012 (median per grant 8, 25th and 75th percentiles 4 and 14, range 0 – 123), which received 2,224,255 citations (median per grant 1048, 25th and 75th percentiles 492 and 1,932, range 0 – 16,295). We found no association between percentile ranking and citation metrics; the absence of association persisted even after accounting for calendar time, grant duration, number of grants acknowledged per paper, number of authors per paper, early investigator status, human versus non-human focus, and institutional funding. An exploratory machine-learning analysis suggested that grants with the very best percentile rankings did yield more maximally cited papers. Conclusions In a large cohort of NHLBI-funded cardiovascular R01 grants, we were unable to find a monotonic association between better percentile ranking and higher scientific impact as assessed by citation metrics. PMID:24406983 20. Dynamic Contrast-Enhanced MRI of Cervical Cancers: Temporal Percentile Screening of Contrast Enhancement Identifies Parameters for Prediction of Chemoradioresistance SciTech Connect Andersen, Erlend K.F.; Hole, Knut Hakon; Lund, Kjersti V.; Sundfor, Kolbein; Kristensen, Gunnar B.; Lyng, Heidi; Malinen, Eirik 2012-03-01 Purpose: To systematically screen the tumor contrast enhancement of locally advanced cervical cancers to assess the prognostic value of two descriptive parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Methods and Materials: This study included a prospectively collected cohort of 81 patients who underwent DCE-MRI with gadopentetate dimeglumine before chemoradiotherapy. The following descriptive DCE-MRI parameters were extracted voxel by voxel and presented as histograms for each time point in the dynamic series: normalized relative signal increase (nRSI) and normalized area under the curve (nAUC). The first to 100th percentiles of the histograms were included in a log-rank survival test, resulting in p value and relative risk maps of all percentile-time intervals for each DCE-MRI parameter. The maps were used to evaluate the robustness of the individual percentile-time pairs and to construct prognostic parameters. Clinical endpoints were locoregional control and progression-free survival. The study was approved by the institutional ethics committee. Results: The p value maps of nRSI and nAUC showed a large continuous region of percentile-time pairs that were significantly associated with locoregional control (p < 0.05). These parameters had prognostic impact independent of tumor stage, volume, and lymph node status on multivariate analysis. Only a small percentile-time interval of nRSI was associated with progression-free survival. Conclusions: The percentile-time screening identified DCE-MRI parameters that predict long-term locoregional control after chemoradiotherapy of cervical cancer. 1. Analysis of the Stability of Teacher-Level Growth Scores from the Student Growth Percentile Model. REL 2016-104 ERIC Educational Resources Information Center Lash, Andrea; Makkonen, Reino; Tran, Loan; Huang, Min 2016-01-01 This study, undertaken at the request of the Nevada Department of Education, examined the stability over years of teacher-level growth scores from the Student Growth Percentile (SGP) model, which many states and districts have selected as a measure of effectiveness in their teacher evaluation systems. The authors conducted a generalizability study… 2. Standard Errors of Equating for the Percentile Rank-Based Equipercentile Equating with Log-Linear Presmoothing ERIC Educational Resources Information Center Wang, Tianyou 2009-01-01 Holland and colleagues derived a formula for analytical standard error of equating using the delta-method for the kernel equating method. Extending their derivation, this article derives an analytical standard error of equating procedure for the conventional percentile rank-based equipercentile equating with log-linear smoothing. This procedure is… 3. Validation of the 5th and 95th Percentile Hybrid III Anthropomorphic Test Device Finite Element Model NASA Technical Reports Server (NTRS) Lawrence, C.; Somers, J. T.; Baldwin, M. A.; Wells, J. A.; Newby, N.; Currie, N. J. 2014-01-01 NASA spacecraft design requirements for occupant protection are a combination of the Brinkley criteria and injury metrics extracted from anthropomorphic test devices (ATD's). For the ATD injury metrics, the requirements specify the use of the 5th percentile female Hybrid III and the 95th percentile male Hybrid III. Furthermore, each of these ATD's is required to be fitted with an articulating pelvis and a straight spine. The articulating pelvis is necessary for the ATD to fit into spacecraft seats, while the straight spine is required as injury metrics for vertical accelerations are better defined for this configuration. The requirements require that physical testing be performed with both ATD's to demonstrate compliance. Before compliance testing can be conducted, extensive modeling and simulation are required to determine appropriate test conditions, simulate conditions not feasible for testing, and assess design features to better ensure compliance testing is successful. While finite element (FE) models are currently available for many of the physical ATD's, currently there are no complete models for either the 5th percentile female or the 95th percentile male Hybrid III with a straight spine and articulating pelvis. The purpose of this work is to assess the accuracy of the existing Livermore Software Technology Corporation's FE models of the 5th and 95th percentile ATD's. To perform this assessment, a series of tests will be performed at Wright Patterson Air Force Research Lab using their horizontal impact accelerator sled test facility. The ATD's will be placed in the Orion seat with a modified-advanced-crew-escape-system (MACES) pressure suit and helmet, and driven with loadings similar to what is expected for the actual Orion vehicle during landing, launch abort, and chute deployment. Test data will be compared to analytical predictions and modelling uncertainty factors will be determined for each injury metric. Additionally, the test data will be used to 4. The Association of Weight Percentile and Motor Vehicle Crash Injury Among 3 to 8 Year Old Children PubMed Central Zonfrillo, Mark R.; Nelson, Kyle A.; Durbin, Dennis R.; Kallan, Michael J. 2010-01-01 The use of age-appropriate child restraint systems significantly reduces injury and death associated with motor vehicle crashes (MVCs). Pediatric obesity has become a global epidemic. Although recent evidence suggests a possible association between pediatric obesity and MVC-related injury, there are potential misclassifications of body mass index from under-estimated height in younger children. Given this limitation, age- and sex-specific weight percentiles can be used as a proxy of weight status. The specific aim of this study was to determine the association between weight percentile and the risk of significant injury for children 3–8 years in MVCs. This was a cross-sectional study of children aged 3–8 years in MVCs in 16 US states, with data collected via insurance claims records and a telephone survey from 12/1/98–11/30/07. Parent-reported injuries with an abbreviated Injury Scale (AIS) score of 2+ indicated a clinically significant injury. Age- and sex-specific weight percentiles were calculated using pediatric norms. The study sample included 9,327 children aged 3–8 years (weighted to represent 157,878 children), of which 0.96% sustained clinically significant injuries. There was no association between weight percentiles and overall injury when adjusting for restraint type (p=0.71). However, increasing weight percentiles were associated with lower extremity injuries at a level that approached significance (p=0.053). Further research is necessary to describe mechanisms for weight-related differences in injury risk. Parents should continue to properly restrain their children in accordance with published guidelines. PMID:21050602 5. Percentile Values for Running Sprint Field Tests in Children Ages 6-17 Years: Influence of Weight Status ERIC Educational Resources Information Center Castro-Pinero, Jose; Gonzalez-Montesinos, Jose Luis; Keating, Xiaofen D.; Mora, Jesus; Sjostrom, Michael; Ruiz, Jonatan R. 2010-01-01 The aim of this study was to provide percentile values for six different sprint tests in 2,708 Spanish children (1,234 girls) ages 6-17.9 years. We also examined the influence of weight status on sprint performance across age groups, with a focus on underweight and obese groups. We used the 20-m, 30-m, and 50-m running sprint standing start and… 6. Application of Radial Basis Function Methods in the Development of a 95th Percentile Male Seated FEA Model. PubMed Vavalle, Nicholas A; Schoell, Samantha L; Weaver, Ashley A; Stitzel, Joel D; Gayzik, F Scott 2014-11-01 Human body finite element models (FEMs) are a valuable tool in the study of injury biomechanics. However, the traditional model development process can be time-consuming. Scaling and morphing an existing FEM is an attractive alternative for generating morphologically distinct models for further study. The objective of this work is to use a radial basis function to morph the Global Human Body Models Consortium (GHBMC) average male model (M50) to the body habitus of a 95th percentile male (M95) and to perform validation tests on the resulting model. The GHBMC M50 model (v. 4.3) was created using anthropometric and imaging data from a living subject representing a 50th percentile male. A similar dataset was collected from a 95th percentile male (22,067 total images) and was used in the morphing process. Homologous landmarks on the reference (M50) and target (M95) geometries, with the existing FE node locations (M50 model), were inputs to the morphing algorithm. The radial basis function was applied to morph the FE model. The model represented a mass of 103.3 kg and contained 2.2 million elements with 1.3 million nodes. Simulations of the M95 in seven loading scenarios were presented ranging from a chest pendulum impact to a lateral sled test. The morphed model matched anthropometric data to within a rootmean square difference of 4.4% while maintaining element quality commensurate to the M50 model and matching other anatomical ranges and targets. The simulation validation data matched experimental data well in most cases. PMID:26192960 7. Seasonal to decadal forcing of high water level percentiles in the German Bight throughout the last century NASA Astrophysics Data System (ADS) Dangendorf, Sönke; Mudersbach, Christoph; Jensen, Jürgen; Anette, Ganske; Heinrich, Hartmut 2013-05-01 For the purpose of coastal planning and management, especially under changing climatic conditions, enhanced knowledge about the evolution of extreme sea levels in the past, present, and future is required. This paper presents statistical analyses of high seasonal water level percentiles of 13 tide gauges in the German Bight, spanning over a period of up to 109 years throughout the twentieth and twenty-first centuries. Seasonal and annual high percentile time series of water levels were investigated in comparison to the mean sea level (MSL) for changes on seasonal, inter-annual, and decadal timescales. While throughout the first half of the twentieth century extreme water levels generally followed changes in MSL, during the second half of the century, linear extreme sea level trends exceeded those in MSL in the order of 9-64 cm per century. The largest, although insignificant, contribution to the magnitude of these trends occurs in the winter season (January to March), while smaller but, due to the generally lower atmospheric variability, significant changes are observed during spring (April to June). The observed multi-decadal trends are generally in good agreement with multi-decadal trends in the corresponding percentiles of local zonal surface winds. Only small parts of the trends remain unexplained. It is suggested that these remaining trends result from modifications in the local tidal regime. For the aspects of coastal planning, the findings clarify that in the German Bight, in addition to changes in MSL, potential changes in storminess and in the tidal regime significantly contribute to the development of extreme water levels. Since these factors have influenced the characteristic of extremes throughout the recent past, they also have to be taken into account when estimating design water levels for, e.g., dikes (in a warming climate) under changing greenhouse gas emissions. 8. Birth Weight Ratio as an Alternative to Birth Weight Percentile to Express Infant Weight in Research and Clinical Practice: A Nationwide Cohort Study PubMed Central Kazemier, Brenda M.; Schuit, Ewoud; Mol, Ben Willem J.; Pajkrt, Eva; Ganzevoort, Wessel 2014-01-01 Objective. To compare birth weight ratio and birth weight percentile to express infant weight when assessing pregnancy outcome. Study Design. We performed a national cohort study. Birth weight ratio was calculated as the observed birth weight divided by the median birth weight for gestational age. The discriminative ability of birth weight ratio and birth weight percentile to identify infants at risk of perinatal death (fetal death and neonatal death) or adverse pregnancy outcome (perinatal death + severe neonatal morbidity) was compared using the area under the curve. Outcomes were expressed stratified by gestational age at delivery separate for birth weight ratio and birth weight percentile. Results. We studied 1,299,244 pregnant women, with an overall perinatal death rate of 0.62%. Birth weight ratio and birth weight percentile have equivalent overall discriminative performance for perinatal death and adverse perinatal outcome. In late preterm infants (33+0–36+6 weeks), birth weight ratio has better discriminative ability than birth weight percentile for perinatal death (0.68 versus 0.63, P 0.01) or adverse pregnancy outcome (0.67 versus 0.60, P < 0.001). Conclusion. Birth weight ratio is a potentially valuable instrument to identify infants at risk of perinatal death and adverse pregnancy outcome and provides several advantages for use in research and clinical practice. Moreover, it allows comparison of groups with different average birth weights. PMID:25197283 9. Speed Calculator NASA Technical Reports Server (NTRS) Burch, John L.; Billions, James C. 1976-01-01 An apparatus for measuring the velocity of a vehicle traveling between first and second measured points. The apparatus includes a cylindrical housing having an open top for receiving a transparent disk. Indicia representing speed calibrations is circumferentially spaced adjacent an outer perimeter of the disk. A stopwatch is carried in the housing below said disk and has a rotatable hand which rotates at a predetermined rate under the indicia. A lamp is carried below the stopwatch for illuminating the indicia carried on the transparent disk. The stopwatch is started when the vehicle passes a first reference point and stopped when the vehicle passes the second reference point. Thus, when the hand is stopped, such points to the calibrated indicia on said disk indicating the velocity of a vehicle. 10. A storm severity index based on return levels of wind speeds NASA Astrophysics Data System (ADS) Becker, Nico; Nissen, Katrin M.; Ulbrich, Uwe 2015-04-01 European windstorms related to extra-tropical cyclones cause considerable damages to infrastructure during the winter season. Leckebusch et al. (2008) introduced a storm severity index (SSI) based on the exceedances of the local 98th percentile of wind speeds. The SSI is based on the assumption that (insured) damage usually occurs within the upper 2%-quantile of the local wind speed distribution (i.e. if the 98th percentile is exceeded). However, critical infrastructure, for example related to the power network or the transportation system, is usually designed to withstand wind speeds reaching the local 50-year return level, which is much higher than the 98th percentile. The aim of this work is to use the 50-year return level to develop a modified SSI, which takes into account only extreme wind speeds relevant to critical infrastructure. As a first step we use the block maxima approach to estimate the spatial distribution of return levels by fitting the generalized extreme value (GEV) distribution to the wind speeds retrieved from different reanalysis products. We show that the spatial distributions of the 50-year return levels derived from different reanalyses agree well within large parts of Europe. The differences between the reanalyses are largely within the range of the uncertainty intervals of the estimated return levels. As a second step the exceedances of the 50-year return level are evaluated and compared to the exceedances of the 98th percentiles for different extreme European windstorms. The areas where the wind speeds exceed the 50-year return level in the reanalysis data do largely agree with the areas where the largest damages were reported, e.g. France in the case of "Lothar" and "Martin" and Central Europe in the case of "Kyrill". Leckebusch, G. C., Renggli, D., & Ulbrich, U. (2008). Development and application of an objective storm severity measure for the Northeast Atlantic region. Meteorologische Zeitschrift, 17(5), 575-587. 11. Dosimetric impacts of microgravity: an analysis of 5th, 50th and 95th percentile male and female astronauts NASA Astrophysics Data System (ADS) Bahadori, Amir A.; Van Baalen, Mary; Shavers, Mark R.; Semones, Edward J.; Bolch, Wesley E. 2012-02-01 Computational phantoms serve an important role in organ dosimetry and risk assessment performed at the National Aeronautics and Space Administration (NASA). A previous study investigated the impact on organ dose equivalents and effective doses from the use of the University of Florida hybrid adult male (UFHADM) and adult female (UFHADF) phantoms at differing height and weight percentiles versus those given by the two existing NASA phantoms, the computerized anatomical man (CAM) and female (CAF) (Bahadori et al 2011 Phys. Med. Biol. 56 1671-94). In the present study, the UFHADM and UFHADF phantoms of different body sizes were further altered to incorporate the effects of microgravity. Body self-shielding distributions are generated using the voxel-based ray tracer (VoBRaT), and the results are combined with depth dose data from the NASA codes BRYNTRN and HZETRN to yield organ dose equivalents and their rates for a variety of space radiation environments. It is found that while organ dose equivalents are indeed altered by the physiological effects of microgravity, the magnitude of the change in overall risk (indicated by the effective dose) is minimal for the spectra and simplified shielding configurations considered. The results also indicate, however, that UFHADM and UFHADF could be useful in designing dose reduction strategies through optimized positioning of an astronaut during encounters with solar particle events. 12. Using a Spreadsheet to Compute the Maximum Wind Sector 99.5th Percentile X/Q Value in Accordance with DOE-STD-3009-2014. PubMed Vickers, Linda 2016-05-01 The U.S. Department of Energy Standard 3009-2014 requires one of two methods to determine the simple Gaussian relative concentration (X/Q) of pollutant at plume centerline downwind to a receptor for a 2-h exposure duration from a ground-level release (i.e., less than 10 m height) which are (1) the 99.5th percentile X/Q for the directionally-dependent method and (2) the 95th percentile X/Q for the directionally-independent method. This paper describes how to determine the simple Gaussian 99.5th percentile X/Q for the directionally-dependent method using an electronic spreadsheet. Refer to a previous paper to determine the simple Gaussian 95th percentile X/Q for the directionally-independent method using an electronic spreadsheet (Vickers 2015). The method described herein is simple, quick, accurate, and transparent because all of the data, calculations, and results are visible for validation and verification. PMID:27023153 13. Percentile Distributions of Median Nitrite Plus Nitrate as Nitrogen, Total Nitrogen, and Total Phosphorus Concentrations in Oklahoma Streams, 1973-2001 USGS Publications Warehouse Haggard, Brian E.; Masoner, Jason R.; Becker, Carol J. 2003-01-01 Nutrients are one of the primary causes of water-quality impairments in streams, lakes, reservoirs, and estuaries in the United States. The U.S. Environmental Protection Agency has developed regional-based nutrient criteria using ecoregions to protect streams in the United States from impairment. However, nutrient criteria were based on nutrient concentrations measured in large aggregated nutrient ecoregions with little relevance to local environmental conditions in states. The Oklahoma Water Resources Board is using a dichotomous process known as Use Support Assessment Protocols to define nutrient criteria in Oklahoma streams. The Oklahoma Water Resources Board is modifying the Use Support Assessment Protocols to reflect nutrient informa-tion and environmental characteristics relevant to Oklahoma streams, while considering nutrient information grouped by geographic regions based on level III ecoregions and state boundaries. Percentile distributions of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorous concentrations were calculated from 563 sites in Oklahoma and 4 sites in Arkansas near the Oklahoma and Arkansas border to facilitate development of nutrient criteria for Oklahoma streams. Sites were grouped into four geographic regions and were categorized into eight stream categories by stream slope and stream order. The 50th percentiles of median nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus concentrations were greater in the Ozark Highland ecoregion and were less in the Ouachita Mountains ecoregion when compared to other geographic areas used to group sites. The 50th percentiles of median concentrations of nitrite plus nitrate as nitrogen, total nitrogen, and total phosphorus were least in first, second, and third order streams. The 50th percentiles of median nitrite plus nitrate as nitrogen, total nitrogen and total phosphorus concentrations in the Ozark Highland and Ouachita Mountains ecoregions were least in 14. An inflatable belt system in the rear seat occupant environment: investigating feasibility and benefit in frontal impact sled tests with a 50th percentile male ATD PubMed Central Forman, Jason L.; Lopez-Valdes, Francisco J.; Dennis, Nate; Kent, Richard W.; Tanji, Hiromasa; Higuchi, Kazuo 2010-01-01 Frontal-impact airbag systems have the potential to provide a benefit to rear seat occupants by distributing restraining forces over the body in a manner not possible using belts alone. This study sought to investigate the effects of incorporating a belt-integrated airbag (“airbelt”) into a rear seat occupant restraint system. Frontal impact sled tests were performed with a Hybrid III 50th percentile male anthropomorphic test device (ATD) seated in the right-rear passenger position of a 2004 mid-sized sedan buck. Tests were performed at 48 km/h (20 g, 100 ms acceleration pulse) and 29 km/h (11 g, 100 ms). The restraints consisted of a 3-point belt system with a cylindrical airbag integrated into the upper portion of the shoulder belt. The airbag was tapered in shape, with a maximum diameter of 16 cm (at the shoulder) that decreased to 4 cm at the mid-chest. A 2.5 kN force-limiter was integrated into the shoulder-belt retractor, and a 2.3 kN pretensioner was present in the out-board anchor of the lap belt. Six ATD tests (three 48 km/h and three 29 km/h) were performed with the airbelt system. These were compared to previous frontal-impact, rear seat ATD tests with a standard (not-force-limited, not-pretensioned) 3-point belt system and a progressive force-limiting (peak 4.4 kN), pretensioning (FL+PT) 3-point belt system. In the 48 km/h tests, the airbelt resulted in significantly less (p<0.05, two-tailed Student’s t-test) posterior displacement of the sternum towards the spine (chest deflection) than both the standard and FL+PT belt systems (airbelt: average 13±1.1 mm standard deviation; standard belt: 33±2.3 mm; FL+PT belt: 23±2.6 mm). This was consistent with a significant reduction in the peak upper shoulder belt force (airbelt: 2.7±0.1 kN; standard belt: 8.7±0.3 kN; FL+PT belt: 4.4±0.1 kN), and was accompanied by a small increase in forward motion of the head (airbelt: 54±0.4 cm; standard belt: 45±1.3 cm; FL+PT belt: 47±1.1 cm) The airbelt system 15. Aircraft Speed Instruments NASA Technical Reports Server (NTRS) Beij, K Hilding 1933-01-01 This report presents a concise survey of the measurement of air speed and ground speed on board aircraft. Special attention is paid to the pitot-static air-speed meter which is the standard in the United States for airplanes. Air-speed meters of the rotating vane type are also discussed in considerable detail on account of their value as flight test instruments and as service instruments for airships. Methods of ground-speed measurement are treated briefly, with reference to the more important instruments. A bibliography on air-speed measurement concludes the report. 16. Speeds of coronal mass ejections: SMM observations from 1980 and 1984-1989 NASA Technical Reports Server (NTRS) Hundhausen, A. J.; Burkepile, J. T.; St. Cyr, O. C. 1994-01-01 The speeds of 936 features in 673 coronal mass ejections have been determined from trajectories observed with the Solar Maximum Mission (SMM) coronagraph in 1980 and 1984 to 1989. The distribution of observed speeds has a range (from 5th to 95th percentile) of 35 to 911 km/s; the average and median speeds are 349 and 285 km/s. The speed distributions of some selected classes of mass ejections are significantly different. For example, the speeds of 331 'outer loops' range from 80 to 1042 km/s; the average and median speeds for this class of ejections are 445 and 372 km/s. The speed distributions from each year of SMM observations show significant changes, with the annual average speeds varying from 157 (1984) to 458 km/s (1985). These variations are not simply related to the solar activity cycle; the annual averages from years near the sunspot maxima and minimum are not significantly different. The widths, latitudes, and speeds of mass ejections determined from the SMM observations are only weakly correlated. In particular, mass ejection speeds vary only slightly with the heliographic latitudes of the ejection. High-latitude ejections, which occur well poleward of the active latitudes, have speeds similar to active latitude ejections. 17. Vehicle speed control device SciTech Connect Thornton-Trump, W.E. 1987-03-10 An apparatus is described for automatically limiting the speed of a vehicle powered by an internal combustion engine having a spark ignition system with an ignition coil, comprising: sensor means for generating a speed signal directly representative of the speed of the vehicle comprising a series of speed signal pulses having a pulse repetition frequency proportional to the speed of the vehicle; control means for converting speed signal pulses into a DC voltage proportional to the vehicle speed; means for comparing the DC voltage to a predetermined DC voltage having substantially zero AC components representative of a predetermined maximum speed and for generating a difference signal in response thereto; and means for generating a pulse-width modulated control signal responsive to the difference signal; power means responsive to the control signal for intermittently interrupting the ignition system. 18. Small portable speed calculator NASA Technical Reports Server (NTRS) Burch, J. L.; Billions, J. C. 1973-01-01 Calculator is adapted stopwatch calibrated for fast accurate measurement of speeds. Single assembled unit is rugged, self-contained, and relatively inexpensive to manufacture. Potential market includes automobile-speed enforcement, railroads, and field-test facilities. 19. Is the 90th Percentile Adequate? The Optimal Waist Circumference Cutoff Points for Predicting Cardiovascular Risks in 124,643 15-Year-Old Taiwanese Adolescents PubMed Central Ho, ChinYu; Chen, Hsin-Jen; Huang, Nicole; Yeh, Jade Chienyu; deFerranti, Sarah 2016-01-01 Adolescent obesity has increased to alarming proportions globally. However, few studies have investigated the optimal waist circumference (WC) of Asian adolescents. This study sought to establish the optimal WC cutoff points that identify a cluster of cardiovascular risk factors (CVRFs) among 15-year-old ethnically Chinese adolescents. This study was a regional population-based study on the CVRFs among adolescents who enrolled in all the senior high schools in Taipei City, Taiwan, between 2011 and 2014. Four cross-sectional health examinations of first-year senior high school (grade 10) students were conducted from September to December of each year. A total of 124,643 adolescents aged 15 (boys: 63,654; girls: 60,989) were recruited. Participants who had at least three of five CVRFs were classified as the high-risk group. We used receiver-operating characteristic curves and the area under the curve (AUC) to determine the optimal WC cutoff points and the accuracy of WC in predicting high cardiovascular risk. WC was a good predictor for high cardiovascular risk for both boys (AUC: 0.845, 95% confidence interval [CI]: 0.833–0.857) and girls (AUC: 0.763, 95% CI: 0.731–0.795). The optimal WC cutoff points were ≥78.9 cm for boys (77th percentile) and ≥70.7 cm for girls (77th percentile). Adolescents with normal weight and an abnormal WC were more likely to be in the high cardiovascular risk group (odds ratio: 3.70, 95% CI: 2.65–5.17) compared to their peers with normal weight and normal WC. The optimal WC cutoff point of 15-year-old Taiwanese adolescents for identifying CVRFs should be the 77th percentile; the 90th percentile of the WC might be inadequate. The high WC criteria can help health professionals identify higher proportion of the adolescents with cardiovascular risks and refer them for further evaluations and interventions. Adolescents’ height, weight and WC should be measured as a standard practice in routine health checkups. PMID:27389572 20. Is the 90th Percentile Adequate? The Optimal Waist Circumference Cutoff Points for Predicting Cardiovascular Risks in 124,643 15-Year-Old Taiwanese Adolescents. PubMed Lee, Jason Jiunshiou; Ho, ChinYu; Chen, Hsin-Jen; Huang, Nicole; Yeh, Jade Chienyu; deFerranti, Sarah 2016-01-01 Adolescent obesity has increased to alarming proportions globally. However, few studies have investigated the optimal waist circumference (WC) of Asian adolescents. This study sought to establish the optimal WC cutoff points that identify a cluster of cardiovascular risk factors (CVRFs) among 15-year-old ethnically Chinese adolescents. This study was a regional population-based study on the CVRFs among adolescents who enrolled in all the senior high schools in Taipei City, Taiwan, between 2011 and 2014. Four cross-sectional health examinations of first-year senior high school (grade 10) students were conducted from September to December of each year. A total of 124,643 adolescents aged 15 (boys: 63,654; girls: 60,989) were recruited. Participants who had at least three of five CVRFs were classified as the high-risk group. We used receiver-operating characteristic curves and the area under the curve (AUC) to determine the optimal WC cutoff points and the accuracy of WC in predicting high cardiovascular risk. WC was a good predictor for high cardiovascular risk for both boys (AUC: 0.845, 95% confidence interval [CI]: 0.833-0.857) and girls (AUC: 0.763, 95% CI: 0.731-0.795). The optimal WC cutoff points were ≥78.9 cm for boys (77th percentile) and ≥70.7 cm for girls (77th percentile). Adolescents with normal weight and an abnormal WC were more likely to be in the high cardiovascular risk group (odds ratio: 3.70, 95% CI: 2.65-5.17) compared to their peers with normal weight and normal WC. The optimal WC cutoff point of 15-year-old Taiwanese adolescents for identifying CVRFs should be the 77th percentile; the 90th percentile of the WC might be inadequate. The high WC criteria can help health professionals identify higher proportion of the adolescents with cardiovascular risks and refer them for further evaluations and interventions. Adolescents' height, weight and WC should be measured as a standard practice in routine health checkups. PMID:27389572 1. Rain-aerosol relationships influenced by wind speed NASA Astrophysics Data System (ADS) Yang, Yang; Russell, Lynn M.; Lou, Sijia; Liu, Ying; Singh, Balwinder; Ghan, Steven J. 2016-03-01 Aerosol optical depth (AOD) has been shown to correlate with precipitation rate (R) in recent studies. The R-AOD relationships over oceans are examined in this study using 150 year simulations with the Community Earth System Model. Through partial correlation analysis, with the influence of 10 m wind speed removed, R-AOD relationships exert a change from positive to negative over the midlatitude oceans, indicating that wind speed makes a large contribution to the relationships by changing the sea-salt emissions. A simulation with prescribed sea-salt emissions shows that wind speed leads to increasing R by +0.99 mm d-1 averaged globally, offsetting 64% of the wet scavenging-induced decrease between polluted and clean conditions, defined according to percentiles of AOD. These demonstrate that wind speed is one of the major drivers of R-AOD relationships. Relative humidity at 915 hPa can also result in the positive relationships; however, its role is smaller than that of wind speed. 2. Vehicle speed control system SciTech Connect Yoshida, D.; Tanno, T.; Fukunaga, T. 1987-06-16 This patent describes a vehicle speed control system for performing vehicle speed control by controlling the displacement of at least one of a hydraulic pump and a hydraulic motor of a hydraulic transmission through an electric servo device, comprising: vehicle speed setting means for generating a voltage signal corresponding to a vehicle speed to be set; compensating means interposed between the vehicle speed setting means and the electric servo device, the compensating means comprising a first delay element; and second delay element having a response characteristic slower than that of the first delay element. A selecting means for judging as to whether a voltage signal changed by the operation of the vehicle speed setting means represents an acceleration command or a deceleration command and for selecting the first delay element when the voltage signal represents an acceleration command and for selecting the second delay element when the voltage signal represents a deceleration command. 3. High speed handpieces PubMed Central Bhandary, Nayan; Desai, Asavari; Shetty, Y Bharath 2014-01-01 High speed instruments are versatile instruments used by clinicians of all specialties of dentistry. It is important for clinicians to understand the types of high speed handpieces available and the mechanism of working. The centers for disease control and prevention have issued guidelines time and again for disinfection and sterilization of high speed handpieces. This article presents the recent developments in the design of the high speed handpieces. With a view to prevent hospital associated infections significant importance has been given to disinfection, sterilization & maintenance of high speed handpieces. How to cite the article: Bhandary N, Desai A, Shetty YB. High speed handpieces. J Int Oral Health 2014;6(1):130-2. PMID:24653618 4. 46 CFR 154.1864 - Vessel speed within speed reduction. Code of Federal Regulations, 2013 CFR 2013-10-01 ... 46 Shipping 5 2013-10-01 2013-10-01 false Vessel speed within speed reduction. 154.1864 Section... Vessel speed within speed reduction. The master shall ensure that the speed of the vessel is not greater than the posted speed reduction.... 5. 46 CFR 154.1864 - Vessel speed within speed reduction. Code of Federal Regulations, 2012 CFR 2012-10-01 ... 46 Shipping 5 2012-10-01 2012-10-01 false Vessel speed within speed reduction. 154.1864 Section... Vessel speed within speed reduction. The master shall ensure that the speed of the vessel is not greater than the posted speed reduction.... 6. 46 CFR 154.1864 - Vessel speed within speed reduction. Code of Federal Regulations, 2014 CFR 2014-10-01 ... 46 Shipping 5 2014-10-01 2014-10-01 false Vessel speed within speed reduction. 154.1864 Section... Vessel speed within speed reduction. The master shall ensure that the speed of the vessel is not greater than the posted speed reduction.... 7. 46 CFR 154.1864 - Vessel speed within speed reduction. Code of Federal Regulations, 2011 CFR 2011-10-01 ... 46 Shipping 5 2011-10-01 2011-10-01 false Vessel speed within speed reduction. 154.1864 Section... Vessel speed within speed reduction. The master shall ensure that the speed of the vessel is not greater than the posted speed reduction.... 8. 46 CFR 154.1864 - Vessel speed within speed reduction. Code of Federal Regulations, 2010 CFR 2010-10-01 ... 46 Shipping 5 2010-10-01 2010-10-01 false Vessel speed within speed reduction. 154.1864 Section... Vessel speed within speed reduction. The master shall ensure that the speed of the vessel is not greater than the posted speed reduction.... 9. Computer ray tracing speeds. PubMed Robb, P; Pawlowski, B 1990-05-01 The results of measuring the ray trace speed and compilation speed of thirty-nine computers in fifty-seven configurations, ranging from personal computers to super computers, are described. A correlation of ray trace speed has been made with the LINPACK benchmark which allows the ray trace speed to be estimated using LINPACK performance data. The results indicate that the latest generation of workstations, using CPUs based on RISC (Reduced Instruction Set Computer) technology, are as fast or faster than mainframe computers in compute-bound situations. PMID:20563112 10. Nonintrusive shaft speed sensor NASA Technical Reports Server (NTRS) Barkhoudarian, S.; Wyett, L.; Maram, J. 1985-01-01 Reusable rocket engines such as the Space Shuttle Main Engines (SSME), the Orbital Transfer Vehicles (OTV), etc., have throttling capabilities that require real-time, closed-loop control systems of engine propellant flows, combustion temperatures and pressures, and turbopump rotary speeds. In the case of the SSME, there are four turbopumps that require real-time measurement and control of their rotary speeds. Variable-reluctance magnetic speed sensors were designed, fabricated, and tested for all four turbopumps, resulting in the successful implementation and operation of three of these speed sensors during each of the 12 Shuttle flights. 11. Association of percentile ranking with citation impact and productivity in a large cohort of de novo NIMH-funded R01 grants. PubMed Doyle, J M; Quinn, K; Bodenstein, Y A; Wu, C O; Danthi, N; Lauer, M S 2015-09-01 Previous reports from National Institutes of Health and National Science Foundation have suggested that peer review scores of funded grants bear no association with grant citation impact and productivity. This lack of association, if true, may be particularly concerning during times of increasing competition for increasingly limited funds. We analyzed the citation impact and productivity for 1755 de novo investigator-initiated R01 grants funded for at least 2 years by National Institute of Mental Health between 2000 and 2009. Consistent with previous reports, we found no association between grant percentile ranking and subsequent productivity and citation impact, even after accounting for subject categories, years of publication, duration and amounts of funding, as well as a number of investigator-specific measures. Prior investigator funding and academic productivity were moderately strong predictors of grant citation impact. PMID:26033238 12. Thoracic response targets for a computational model: a hierarchical approach to assess the biofidelity of a 50th-percentile occupant male finite element model. PubMed Poulard, David; Kent, Richard W; Kindig, Matthew; Li, Zuoping; Subit, Damien 2015-05-01 Current finite element human thoracic models are typically evaluated against a limited set of loading conditions; this is believed to limit their capability to predict accurate responses. In this study, a 50th-percentile male finite element model (GHBMC v4.1) was assessed under various loading environments (antero-posterior rib bending, point loading of the denuded ribcage, omnidirectional pendulum impact and table top) through a correlation metric tool (CORA) based on linearly independent signals. The load cases were simulated with the GHBMC model and response corridors were developed from published experimental data. The model was found to be in close agreement with the experimental data both qualitatively and quantitatively (CORA ratings above 0.75) and the response of the thorax was overall deemed biofidelic. This study also provides relevant corridors and an objective rating framework that can be used for future evaluation of thoracic models. PMID:25681717 13. Perceptual countermeasures to speeding. PubMed Fildes, Brian; Corben, Bruce; Newstead, Stuart; Macaulay, Jemima; Gunatillake, Thanuja; Tziotis, Michael 2005-01-01 An on-road evaluation of two perceptual countermeasure treatments (an enhanced curve post treatment and peripheral transverse edgelines on the approach to an intersection) was conducted over one year to indicate potential for reducing travel speed. Measures included speed and deceleration profiles, braking, and lateral placement observations taken from video recordings at each site. Data were collected before treatment, immediately after treatment, and 12 months after treatment. The results obtained were quite variable across sites and treatments. At curves, speed effects were mixed with both speed reductions and increases observed immediately after and 12-months later. Braking results tended to support travel speed findings and some improvement in lateral placement were also observed at these locations. At intersections, the results were more stable where speed reductions were more common both immediately after treatment as well as longer-term. There were no differences in braking and lateral placement at these straight-road locations. The findings seem to have been unduly influenced to some degree by misadventure and wear and tear at these sites. It is argued that while the effectiveness of these treatments may be site specific to some degree, they do offer a low-cost solution to reducing travel speed at hazardous locations. PMID:16179136 14. High Speed Civil Transport NASA Technical Reports Server (NTRS) 1997-01-01 This computer generated animation depicts a conceptual simulation of the flight of a High Speed Civil Transport (HSCT). As envisioned, the HSCT is a next-generation supersonic (faster than the speed of sound) passenger jet that would fly 300 passengers at more than 1,500 miles per hour -- more than twice the speed of sound. It will cross the Pacific or Atlantic in less than half the time of modern subsonic jets, and at a ticket price less than 20 percent above comparable, slower flights. 15. Engine speed control apparatus SciTech Connect Ishii, M.; Miyazaki, M.; Nakamura, N.; Kakinuma, H. 1986-11-04 This patent describes an engine speed control apparatus. The system comprises an actuator for adjusting an engine speed, a first unit for computing a desired engine speed, a second unit for detecting the actual engine speed, and a third unit for detecting the difference between the outputs of the first and second units. The system also includes a fourth unit for computing a control pulse width for the actuator in accordance with the output of the third unit, a fifth unit for generating a control signal, a sixth unit for driving the actuator in response to the output of the fifth unit, and a seventh unit for computing an optimal halt time to interrupt the driving of the actuator. The actuator is driven intermittently in conformity in the control pulse width and the halt time. 16. High Speed data acquisition SciTech Connect Cooper, Peter S. 1998-02-01 A general introduction to high Speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E781) high statistics charmed baryon production and decay experiment now taking data at Fermilab. 17. Speeding earthquake disaster relief USGS Publications Warehouse Mortensen, Carl; Donlin, Carolyn; Page, Robert A.; Ward, Peter 1995-01-01 In coping with recent multibillion-dollar earthquake disasters, scientists and emergency managers have found new ways to speed and improve relief efforts. This progress is founded on the rapid availability of earthquake information from seismograph networks. 18. High Speed Research Program NASA Technical Reports Server (NTRS) Anderson, Robert E.; Corsiglia, Victor R.; Schmitz, Frederic H. (Technical Monitor) 1994-01-01 An overview of the NASA High Speed Research Program will be presented from a NASA Headquarters perspective. The presentation will include the objectives of the program and an outline of major programmatic issues. 19. The use of the percentile method for searching empirical relationships between compression strength (UCS), Point Load (Is50) and Schmidt Hammer (RL) Indices NASA Astrophysics Data System (ADS) Bruno, Giovanni; Bobbo, Luigi; Vessia, Giovanna 2014-05-01 Is50 and RL indices are commonly used to indirectly estimate the compression strength of a rocky deposit by in situ and in laboratory devices. The widespread use of Point load and Schmidt hammer tests is due to the simplicity and the speediness of the execution of these tests. Their indices can be related to the UCS by means of the ordinary least square regression analyses. Several researchers suggest to take into account the lithology to build high correlated empirical expressions (R2 >0.8) to draw UCS from Is50 or RL values. Nevertheless, the lower and upper bounds of the UCS ranges of values that can be estimated by means of the two indirect indices are not clearly defined yet. Aydin (2009) stated that the Schmidt hammer test shall be used to assess the compression resistance of rocks characterized by UCS>12-20 MPa. On the other hand, the Point load measures can be performed on weak rocks but upper bound values for UCS are not suggested. In this paper, the empirical relationships between UCS, RL and Is50 are searched by means of the percentile method (Bruno et al. 2013). This method is based on looking for the best regression function, between measured data of UCS and one of the indirect indices, drawn from a subset sample of the couples of measures that are the percentile values. These values are taken from the original dataset of both measures by calculating the cumulative function. No hypothesis on the probability distribution of the sample is needed and the procedure shows to be robust with respect to odd values or outliers. In this study, the carbonate sedimentary rocks are investigated. According to the rock mass classification of Dobereiner and De Freitas (1986), the UCS values for the studied rocks range between 'extremely weak' to 'strong'. For the analyzed data, UCS varies between 1,18-270,70 MPa. Thus, through the percentile method the best empirical relationships UCS-Is50 and UCS-RL are plotted. Relationships between Is50 and RL are drawn, too 20. Increased Physical Activity and Fitness above the 50(th) Percentile Avoid the Threat of Older Adults Becoming Institutionalized: A Cross-sectional Pilot Study. PubMed Pereira, Catarina; Fernandes, Jorge; Raimundo, Armando; Biehl-Printes, Clarissa; Marmeleira, José; Tomas-Carus, Pablo 2016-02-01 The objective of this study was to analyze the impact of physical fitness and physical activity on the threat of older adults without cognitive impairment becoming institutionalized. This cross-sectional study involved 195 non-institutionalized (80.1 ± 4.4 years) and 186 institutionalized (83.8 ± 5.2years) participants. Cognitive impairment was assessed using Mini-Mental State Examination, measures of physical fitness were determined by the Senior Fitness Test, and physical activity was assessed using the International Physical Activity Questionnaire. Multivariate binary logistic analysis selected four main determinants of institutionalization in both genders: The likelihood of becoming institutionalized increased by +18.6% for each additional year of age, whereas it decreased by -24.8% by each fewer kg/m(2) in body mass index (BMI), by -0.9% for each additional meter performed in the aerobic endurance test, and by -2.0% for each additional 100 metabolic equivalent of task (MET)-min/week of physical activity expenditure (p < 0.05). Values ≤50(th) percentile (age ≥81 years, BMI ≥26.7 kg/m(2), aerobic endurance ≤367.6 meters, and physical activity ≤693 MET-min/week) were computed using receiver operating characteristics analysis as cutoffs discriminating institutionalized from non-institutionalized older adults. The performance of physical activity, allied to an improvement in physical fitness (mainly BMI and aerobic endurance), may avoid the threat of institutionalization of older adults without cognitive impairment only if they are above the 50(th) percentile. The following parameters are highly recommended: Expending ≥693 MET-min/week on physical activity, having a BMI ≤26.7 kg/m(2), and being able to walk ≥367.6 meters in the aerobic endurance test, especially above the age of 80 years. The discovery of this trigger justifies the development of physical activity programs targeting the pointed cutoffs in old and very old adults 1. Standing adult human phantoms based on 10th, 50th and 90th mass and height percentiles of male and female Caucasian populations NASA Astrophysics Data System (ADS) Cassola, V. F.; Milian, F. M.; Kramer, R.; de Oliveira Lira, C. A. B.; Khoury, H. J. 2011-07-01 Computational anthropomorphic human phantoms are useful tools developed for the calculation of absorbed or equivalent dose to radiosensitive organs and tissues of the human body. The problem is, however, that, strictly speaking, the results can be applied only to a person who has the same anatomy as the phantom, while for a person with different body mass and/or standing height the data could be wrong. In order to improve this situation for many areas in radiological protection, this study developed 18 anthropometric standing adult human phantoms, nine models per gender, as a function of the 10th, 50th and 90th mass and height percentiles of Caucasian populations. The anthropometric target parameters for body mass, standing height and other body measures were extracted from PeopleSize, a well-known software package used in the area of ergonomics. The phantoms were developed based on the assumption of a constant body-mass index for a given mass percentile and for different heights. For a given height, increase or decrease of body mass was considered to reflect mainly the change of subcutaneous adipose tissue mass, i.e. that organ masses were not changed. Organ mass scaling as a function of height was based on information extracted from autopsy data. The methods used here were compared with those used in other studies, anatomically as well as dosimetrically. For external exposure, the results show that equivalent dose decreases with increasing body mass for organs and tissues located below the subcutaneous adipose tissue layer, such as liver, colon, stomach, etc, while for organs located at the surface, such as breasts, testes and skin, the equivalent dose increases or remains constant with increasing body mass due to weak attenuation and more scatter radiation caused by the increasing adipose tissue mass. Changes of standing height have little influence on the equivalent dose to organs and tissues from external exposure. Specific absorbed fractions (SAFs) have also 2. Speed Reading: Remember the Tortoise ERIC Educational Resources Information Center Graf, Richard G. 1973-01-01 After speed-reading partisans questioned the criticisms in a Psychology Today article, another psychologist conducted a controlled study of speed readers. As we said before, "Speed Readers Don't Read; They Skim". (Editor) 3. Everyone Deserves a Speeding Ticket. ERIC Educational Resources Information Center Burris, Harold 1993-01-01 Presents a first day physics activity having students determine the fine for a speeding ticket if the speeds considered include the earth's rotation and revolution speed, and the movement through the galaxy. (MDH) 4. Dosimetry of infant exposure to power-frequency magnetic fields: variation of 99th percentile induced electric field value by posture and skin-to-skin contact. PubMed Li, Congsheng; Wu, Tongning 2015-04-01 Infant exposure to 50 Hz magnetic fields from power lines was numerically analyzed in this study. Dosimetric variability due to posture and skin-to-skin contact was evaluated using human anatomical models including a recently developed model of a 12-months-old infant. As proposed by the International Commission on Non-Ionizing Radiation Protection, the induced E-field strength (99th percentile value, E99 ) for the central nerve systems (E99_CNS ) and peripheral nerve system (E99_PNS ), were used as metrics. Results showed that the single (free of contact with others) infant model has lower E99 (E99_CNS and E99_PNS inclusive) compared with single adult and child models when exposed to the same power-frequency magnetic field. Also, studied postures of sitting, standing, or arm-up, would not change E99 _PNS . However, skin-to-skin contact with other models could significantly raise induced E-field strength in the infant (e.g., contact on 0.93% of the infant's total surface increased E99_PNS by 213%). Simulations with canonical models were conducted to assess different factors contributing to the E99 enhancement. Results indicated the importance of thoroughly investigating the conservativeness of current safety guidelines in the case of skin-to-skin contact, especially with infants. PMID:25708724 5. Effect of Anatomical Modeling on Space Radiation Dose Estimates: A Comparison of Doses for NASA Phantoms and 5th, 50th, and 95th Percentile UF Hybrid Phantoms NASA Technical Reports Server (NTRS) Bahadori, A.; VanBaalen, M.; Shavers, M.; Semones, E.; Dodge, C.; Bolch, W. 2010-01-01 The estimate of absorbed dose to individual organs of a space crewmember is affected by the geometry of the anatomical model of the astronaut used in the radiation transport calculation. For astronaut dosimetry, NASA currently uses the computerized anatomical male (CAM) and computerized anatomical female (CAF) stylized phantoms to represent astronauts in its operational radiation dose analyses. These phantoms are available in one size and in two body positions. In contrast, the UF Hybrid Adult Male and Female (UFHADM and UFHADF) phantoms have organ shapes based on actual CT data. The surfaces of these phantoms are defined by non-uniform rational B-spline surfaces, and are thus flexible in terms of body morphometry and extremity positioning. In this study, UFHADM and UFHADF are scaled to dimensions corresponding to 5th, 50th, and 95th percentile (PCTL) male and female astronauts. A ray-tracing program is written in Visual Basic 2008, which is then used to create areal density maps for dose points corresponding to various organs within the phantoms. The areal density maps, along with appropriate space radiation spectra, are input into the NASA program couplet HZETRN/BRYNTRN, and organ doses are calculated. The areal density maps selected tissues and organs of the 5th, 50th, and 95th PCTL male and female phantoms are presented and compared. In addition, the organ doses for the 5th, 50th, and 95th PCTL male and female phantoms are presented and compared to organ doses for CAM and CAF. 6. SPEEDE Made Easy. ERIC Educational Resources Information Center Palmer, Barbara H.; Wei, P. Betty 1993-01-01 A nontechnical overview of electronic data interchange (EDI) and of the SPEEDE/ExPRESS Project, which uses EDI to transmit transcripts between schools and colleges, is presented. It explores the fundamental value of the technology, specific costs and benefits, and its potential to transform the delivery of academic support services. (Author/MSE) 7. Transition at hypersonic speeds NASA Technical Reports Server (NTRS) Morkovin, Mark V. 1987-01-01 Certain conjectures on the physics of instabilities in high-speed flows are discussed and the state of knowledge of hypersonic transition summarized. The case is made for an unpressured systematic research program in this area consisting of controlled microscopic experiments, theory, and numerical simulations. 8. High Speed data acquisition SciTech Connect Cooper, P.S. 1998-02-01 A general introduction to high Speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E781) high statistics charmed baryon production and decay experiment now taking data at Fermilab. {copyright} {ital 1998 American Institute of Physics.} 9. High speed civil transport NASA Technical Reports Server (NTRS) Mcknight, R. L. 1992-01-01 The design requirements of the High Speed Civil Transport (HSCT) are discussed. The following design concerns are presented: (1) environmental impact (emissions and noise); (2) critical components (the high temperature combustor and the lightweight exhaust nozzle); and (3) advanced materials (high temperature ceramic matrix composites (CMC's)/intermetallic matrix composites (IMC's)/metal matrix composites (MMC's)). 10. Cloud shadow speed sensor NASA Astrophysics Data System (ADS) Fung, V.; Bosch, J. L.; Roberts, S. W.; Kleissl, J. 2014-06-01 Changing cloud cover is a major source of solar radiation variability and poses challenges for the integration of solar energy. A compact and economical system is presented that measures cloud shadow motion vectors to estimate power plant ramp rates and provide short-term solar irradiance forecasts. The cloud shadow speed sensor (CSS) is constructed using an array of luminance sensors and a high-speed data acquisition system to resolve the progression of cloud passages across the sensor footprint. An embedded microcontroller acquires the sensor data and uses a cross-correlation algorithm to determine cloud shadow motion vectors. The CSS was validated against an artificial shading test apparatus, an alternative method of cloud motion detection from ground-measured irradiance (linear cloud edge, LCE), and a UC San Diego sky imager (USI). The CSS detected artificial shadow directions and speeds to within 15° and 6% accuracy, respectively. The CSS detected (real) cloud shadow directions and speeds with average weighted root-mean-square difference of 22° and 1.9 m s-1 when compared to USI and 33° and 1.5 m s-1 when compared to LCE results. 11. Cloud speed sensor NASA Astrophysics Data System (ADS) Fung, V.; Bosch, J. L.; Roberts, S. W.; Kleissl, J. 2013-10-01 Changing cloud cover is a major source of solar radiation variability and poses challenges for the integration of solar energy. A compact and economical system that measures cloud motion vectors to estimate power plant ramp rates and provide short term solar irradiance forecasts is presented. The Cloud Speed Sensor (CSS) is constructed using an array of luminance sensors and high-speed data acquisition to resolve the progression of cloud passages across the sensor footprint. An embedded microcontroller acquires the sensor data and uses a cross-correlation algorithm to determine cloud motion vectors. The CSS was validated against an artificial shading test apparatus, an alternative method of cloud motion detection from ground measured irradiance (Linear Cloud Edge, LCE), and a UC San Diego Sky Imager (USI). The CSS detected artificial shadow directions and speeds to within 15 and 6% accuracy, respectively. The CSS detected (real) cloud directions and speeds without average bias and with average weighted root mean square difference of 22° and 1.9 m s-1 when compared to USI and 33° and 1.5 m s-1 when compared to LCE results. 12. High speed door assembly DOEpatents Shapiro, Carolyn 1993-01-01 A high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture. 13. High speed door assembly DOEpatents Shapiro, C. 1993-04-27 A high speed door assembly is described, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture. 14. Spindle picker harvest speed effects Technology Transfer Automated Retrieval System (TEKTRAN) The gear drive of a modern John Deere Pro 16 picker unit was modified so that spindle speed was reduced without changing the drum speed. Three 1-row picking units were used in the study, one with the standard drive speeds, one with 25% reduction in spindle drive speed, and one with 50% reduction in... 15. High Speed Vortex Flows NASA Technical Reports Server (NTRS) Wood, Richard M.; Wilcox, Floyd J., Jr.; Bauer, Steven X. S.; Allen, Jerry M. 2000-01-01 A review of the research conducted at the National Aeronautics and Space Administration (NASA), Langley Research Center (LaRC) into high-speed vortex flows during the 1970s, 1980s, and 1990s is presented. The data reviewed is for flat plates, cavities, bodies, missiles, wings, and aircraft. These data are presented and discussed relative to the design of future vehicles. Also presented is a brief historical review of the extensive body of high-speed vortex flow research from the 1940s to the present in order to provide perspective of the NASA LaRC's high-speed research results. Data are presented which show the types of vortex structures which occur at supersonic speeds and the impact of these flow structures to vehicle performance and control is discussed. The data presented shows the presence of both small- and large scale vortex structures for a variety of vehicles, from missiles to transports. For cavities, the data show very complex multiple vortex structures exist at all combinations of cavity depth to length ratios and Mach number. The data for missiles show the existence of very strong interference effects between body and/or fin vortices and the downstream fins. It was shown that these vortex flow interference effects could be both positive and negative. Data are shown which highlights the effect that leading-edge sweep, leading-edge bluntness, wing thickness, location of maximum thickness, and camber has on the aerodynamics of and flow over delta wings. The observed flow fields for delta wings (i.e. separation bubble, classical vortex, vortex with shock, etc.) are discussed in the context of' aircraft design. And data have been shown that indicate that aerodynamic performance improvements are available by considering vortex flows as a primary design feature. Finally a discussing of a design approach for wings which utilize vortex flows for improved aerodynamic performance at supersonic speed is presented. 16. Variable speed drive NASA Technical Reports Server (NTRS) Obler, H. D. (Inventor) 1983-01-01 A variable speed drive wherein a first embodiment is comprised of a pivotally mounted prime mover coupled to a rotary fluid output device, such as a fan or pump, through a variable and fixed pulley drive arrangement is described. The pivotal position of the prime mover and accordingly the pitch diameter of variable pulley means is controlled in accordance with fluid motor means coupled to the prime mover. This is actuated in response to a fluid feedback control signal derived from a sensed output of the rotary fluid output device. The pivotal motion of the prime mover imparts an arcuate motion to the variable pulley means which effects a speed variation of the rotary fluid output device in accordance with the variation of the pitch diameter ratio of opposing variable and fixed pulley means. 17. High speed civil transport NASA Technical Reports Server (NTRS) Bogardus, Scott; Loper, Brent; Nauman, Chris; Page, Jeff; Parris, Rusty; Steinbach, Greg 1990-01-01 The design process of the High Speed Civil Transport (HSCT) combines existing technology with the expectation of future technology to create a Mach 3.0 transport. The HSCT was designed to have a range in excess of 6000 nautical miles and carry up to 300 passengers. This range will allow the HSCT to service the economically expanding Pacific Basin region. Effort was made in the design to enable the aircraft to use conventional airports with standard 12,000 foot runways. With a takeoff thrust of 250,000 pounds, the four supersonic through-flow engines will accelerate the HSCT to a cruise speed of Mach 3.0. The 679,000 pound (at takeoff) HSCT is designed to cruise at an altitude of 70,000 feet, flying above most atmospheric disturbances. 18. Variable speed controller NASA Technical Reports Server (NTRS) Estes, Christa; Spiggle, Charles; Swift, Shannon; Vangeffen, Stephen; Younger, Frank 1992-01-01 This report details a new design for a variable speed controller which can be used to operate lunar machinery without the astronaut using his or her upper body. In order to demonstrate the design, a treadle for an industrial sewing machine was redesigned to be used by a standing operator. Since the invention of an electrically powered sewing machine, the operator has been seated. Today, companies are switching from sit down to stand up operation involving modular stations. The old treadle worked well with a sitting operator, but problems have been found when trying to use the same treadle with a standing operator. Emphasis is placed on the ease of use by the operator along with the ergonomics involved. Included with the design analysis are suggestions for possible uses for the speed controller in other applications. 19. High speed door assembly SciTech Connect Shapiro, C. 1991-12-31 This invention is comprised of a high speed door assembly, comprising an actuator cylinder and piston rods, a pressure supply cylinder and fittings, an electrically detonated explosive bolt, a honeycomb structured door, a honeycomb structured decelerator, and a structural steel frame encasing the assembly to close over a 3 foot diameter opening within 50 milliseconds of actuation, to contain hazardous materials and vapors within a test fixture. 20. Two-speed transaxle DOEpatents Kalns, Ilmars 1981-01-01 Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle. 1. Do speed cameras reduce speeding in urban areas? PubMed Oliveira, Daniele Falci de; Friche, Amélia Augusta de Lima; Costa, Dário Alves da Silva; Mingoti, Sueli Aparecida; Caiaffa, Waleska Teixeira 2015-11-01 This observational study aimed to estimate the prevalence of speeding on urban roadways and to analyze associated factors. The sample consisted of 8,565 vehicles circulating in areas with and without fixed speed cameras in operation. We found that 40% of vehicles 200 meters after the fixed cameras and 33.6% of vehicles observed on roadways without speed cameras were moving over the speed limit (p < 0.001). Motorcycles showed the highest recorded speed (126km/h). Most drivers were men (87.6%), 3.3% of all drivers were using their cell phones, and 74.6% of drivers (not counting motorcyclists) were wearing their seatbelts. On roadway stretches without fixed speed cameras, more women drivers were talking on their cell phones and wearing seatbelts when compared to men (p < 0.05 for both comparisons), independently of speed limits. The results suggest that compliance with speed limits requires more than structural interventions. PMID:26648375 2. The Relation of Speeded and Unspeeded Reasoning with Mental Speed. ERIC Educational Resources Information Center Wilhelm, Oliver; Schulze, Ralf 2002-01-01 Studied the contribution of mental speed to task performance on reasoning tasks under timed and untimed conditions for 227 participants and for 90 participants working under time conditions. Results suggest that the use of speeded reasoning tests is likely to lead to overestimates of the relation between mental speed and reasoning ability. (SLD) 3. High speed flywheel DOEpatents McGrath, Stephen V. 1991-01-01 A flywheel for operation at high speeds utilizes two or more ringlike coments arranged in a spaced concentric relationship for rotation about an axis and an expansion device interposed between the components for accommodating radial growth of the components resulting from flywheel operation. The expansion device engages both of the ringlike components, and the structure of the expansion device ensures that it maintains its engagement with the components. In addition to its expansion-accommodating capacity, the expansion device also maintains flywheel stiffness during flywheel operation. 4. Using Microsoft Excel to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI). PubMed Vickers, Linda D 2010-05-01 This paper describes the method using Microsoft Excel (Microsoft Corporation One Microsoft Way Redmond, WA 98052-6399) to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI) in accordance with guidance from DOE-STD-3009-1994 and U.S. NRC Regulatory Guide 1.145-1982. The accurate determination of the 5% overall site X/Q value is the most important factor in the computation of the 95th percentile of the distribution of doses to the nearest MEOI. This method should be used to validate software codes that compute the X/Q. The 95th percentile of the distribution of doses to the nearest MEOI must be compared to the U.S. DOE Evaluation Guide of 25 rem to determine the relative severity of hazard to the public from a postulated, unmitigated design basis accident that involves an offsite release of radioactive material. PMID:20386192 5. A Model of Cognitive Speed. ERIC Educational Resources Information Center Fulford, Catherine P. 2001-01-01 Introduces a model of cognitive speed and considers its relevance to research and practice. Topics include information processing; semantic cognitive flow; compressed speech; speed-reading; cognitive speed and interaction; and implications for distance education, video multimedia, computer-assisted instruction, hypermedia, interactive multimedia,… 6. High speed transient sampler DOEpatents McEwan, Thomas E. 1995-01-01 A high speed sampler comprises a meandered sample transmission line for transmitting an input signal, a straight strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates along the transmission lines. The sampling gates comprise a four terminal diode bridge having a first strobe resistor connected from a first terminal of the bridge to the positive strobe line, a second strobe resistor coupled from the third terminal of the bridge to the negative strobe line, a tap connected to the second terminal of the bridge and to the sample transmission line, and a sample holding capacitor connected to the fourth terminal of the bridge. The resistance of the first and second strobe resistors is much higher than the signal transmission line impedance in the preferred system. This results in a sampling gate which applies a very small load on the sample transmission line and on the strobe generator. The sample holding capacitor is implemented using a smaller capacitor and a larger capacitor isolated from the smaller capacitor by resistance. The high speed sampler of the present invention is also characterized by other optimizations, including transmission line tap compensation, stepped impedance strobe line, a multi-layer physical layout, and unique strobe generator design. A plurality of banks of such samplers are controlled for concatenated or interleaved sample intervals to achieve long sample lengths or short sample spacing. 7. High speed transient sampler DOEpatents McEwan, T.E. 1995-11-28 A high speed sampler comprises a meandered sample transmission line for transmitting an input signal, a straight strobe transmission line for transmitting a strobe signal, and a plurality of sampling gates along the transmission lines. The sampling gates comprise a four terminal diode bridge having a first strobe resistor connected from a first terminal of the bridge to the positive strobe line, a second strobe resistor coupled from the third terminal of the bridge to the negative strobe line, a tap connected to the second terminal of the bridge and to the sample transmission line, and a sample holding capacitor connected to the fourth terminal of the bridge. The resistance of the first and second strobe resistors is much higher than the signal transmission line impedance in the preferred system. This results in a sampling gate which applies a very small load on the sample transmission line and on the strobe generator. The sample holding capacitor is implemented using a smaller capacitor and a larger capacitor isolated from the smaller capacitor by resistance. The high speed sampler of the present invention is also characterized by other optimizations, including transmission line tap compensation, stepped impedance strobe line, a multi-layer physical layout, and unique strobe generator design. A plurality of banks of such samplers are controlled for concatenated or interleaved sample intervals to achieve long sample lengths or short sample spacing. 17 figs. 8. High speed packet switching NASA Technical Reports Server (NTRS) 1991-01-01 This document constitutes the final report prepared by Proteon, Inc. of Westborough, Massachusetts under contract NAS 5-30629 entitled High-Speed Packet Switching (SBIR 87-1, Phase 2) prepared for NASA-Greenbelt, Maryland. The primary goal of this research project is to use the results of the SBIR Phase 1 effort to develop a sound, expandable hardware and software router architecture capable of forwarding 25,000 packets per second through the router and passing 300 megabits per second on the router's internal busses. The work being delivered under this contract received its funding from three different sources: the SNIPE/RIG contract (Contract Number F30602-89-C-0014, CDRL Sequence Number A002), the SBIR contract, and Proteon. The SNIPE/RIG and SBIR contracts had many overlapping requirements, which allowed the research done under SNIPE/RIG to be applied to SBIR. Proteon funded all of the work to develop new router interfaces other than FDDI, in addition to funding the productization of the router itself. The router being delivered under SBIR will be a fully product-quality machine. The work done during this contract produced many significant findings and results, summarized here and explained in detail in later sections of this report. The SNIPE/RIG contract was completed. That contract had many overlapping requirements with the SBIR contract, and resulted in the successful demonstration and delivery of a high speed router. The development that took place during the SNIPE/RIG contract produced findings that included the choice of processor and an understanding of the issues surrounding inter processor communications in a multiprocessor environment. Many significant speed enhancements to the router software were made during that time. Under the SBIR contract (and with help from Proteon-funded work), it was found that a single processor router achieved a throughput significantly higher than originally anticipated. For this reason, a single processor router was 9. BMI is not a good indicator for metabolic risk in adolescent girls Technology Transfer Automated Retrieval System (TEKTRAN) BMI (kg/m2) does not provide information about body fat percentile.Adolescents with BMI <85th percentile for age are considered lean and at low risk for metabolic complications. Adolescent girls with low BMI can have high body fat percentile. We hypothesized that these girls are already insulin resi... 10. Computer workstation speeds SciTech Connect Grcar, J.F. 1996-06-01 This report compares the performance of several computers. Some of the machines are discontinued, and some are anticipated, but most are currently installed at Sandia Laboratories. All the computers are personal workstations or departmental servers, except for comparison, one is a Cray C90 mainframe supercomputer (not owned by the Laboratories). A few of the computers have multiple processors, but parallelism is not tested. The time to run three programs is reported for every computer. Unlike many benchmarks, these are complete application programs. They were written and are used at Sandia Laboratories. Also SPECmarks are reported for many computers. These are industry standard performance ratings. They are in general agreement with the speeds of running the Sandia programs. This report concludes with some background material and notes about specific manufacturers. 11. TWO-SPEED DEVICE DOEpatents Brunson, G.S. Jr. 1961-04-01 A two-speed device is described comprising a two-part stop engageable with a follower. The two-pant stop comprises first and second members in threaded engagement with each other. The first member is restrained against rotation but is free to move longitudinally, and the second member is free to move arially and rotatively. Means are provided to impart rotation to the second member. The follower is engageable first with an end of one member and then with the corresponding end of the other member after some relative longitudinal movement of the members with respect to one another due to the rotation of the second member and the holding of the first member against rotation. 12. High speed nozzles task NASA Technical Reports Server (NTRS) Hamed, Awatef 1995-01-01 Supersonic cruise exhaust nozzles for advanced applications are optimized for a high nozzle pressure ratio (NPR) at design supersonic cruise Mach number and altitude. The performance of these nozzles with large expansion ratios are severely degraded for operations at subsonic speeds near sea level for NPR significantly less than the design values. The prediction of over-expanded 2DCD nozzles performance is critical to evaluating the internal losses and to the optimization of the integrated vehicle and propulsion system performance. The reported research work was aimed at validating and assessing existing computational methods and turbulence models for predicting the flow characteristics and nozzle performance at over-expanded conditions. Flow simulations in 2DCD nozzles were performed using five different turbulence models. The results are compared with the experimental data for the wall pressure distribution and thrust and flow coefficients at over-expanded static conditions. 13. HIGH SPEED CAMERA DOEpatents Rogers, B.T. Jr.; Davis, W.C. 1957-12-17 This patent relates to high speed cameras having resolution times of less than one-tenth microseconds suitable for filming distinct sequences of a very fast event such as an explosion. This camera consists of a rotating mirror with reflecting surfaces on both sides, a narrow mirror acting as a slit in a focal plane shutter, various other mirror and lens systems as well as an innage recording surface. The combination of the rotating mirrors and the slit mirror causes discrete, narrow, separate pictures to fall upon the film plane, thereby forming a moving image increment of the photographed event. Placing a reflecting surface on each side of the rotating mirror cancels the image velocity that one side of the rotating mirror would impart, so as a camera having this short a resolution time is thereby possible. 14. Non-intrusive speed sensor NASA Technical Reports Server (NTRS) Wyett, L. 1986-01-01 In Phase I of the Non-Intrusive Speed Sensor program, a computerized literature search was performed to identify candidate technologies for remote, non-intrusive speed sensing applications in Space Shuttle Main Engine (SSME) turbopumps. The three most promising technologies were subjected to experimental evaluation to quantify their performance characteristics under the harsh environmental requirements within the turbopumps. Although the infrared and microwave approaches demonstrated excellent cavitation immunity in laboratory tests, the variable-source magnetic speed sensor emerged as the most viable approach. Preliminary design of this speed sensor encountered no technical obstacles and resulted in viable and feasible speed nut, sensor housing, and sensor coil designs. Phase II of this program developed the variable-source magnetic speed sensor through the detailed design task and guided the design into breadboard fabrication. The speed sensor and its integral speed nut were evaluated at both unit and system level testing. The final room-temperature and cryogenic spin testing of the hardware demonstrated that the sensor was capable of generating sufficient output signal to enable remote speed sensing from 1500 to 40000 rpm over a speed nut/sensor separation of 3.5 inches. 15. Variable speed transmission SciTech Connect Wiens, W.S. 1987-08-11 This patent describes a variable speed transmission for transmitting rotational forces between a first shaft and a second shaft wherein a sprocket is mounted on the first shaft and a variable effective diameter pulley, having opposed inclined chain-belt engaging surfaces, is mounted on the second shaft, an endless chain-belt assembly for transmitting rotational forces. The assembly has side edges thereon, comprising: a first portion defining the edges of the chain-belt assembly and having a plurality of links defining a surface corresponding to the opposed inclined chain-belt engaging surfaces on the pulley; and a second portion intermediate of the first portion having a plurality of links for engaging the teeth on the sprocket, the links being joined by a plurality of pins extending transverse to the links; and a flexible shield mounted over the links and retained relative thereto by the pins wherein the flexible shield surrounds the links of the second portion of the chain-belt assembly and retains lubrication for the second portion and to prevent same for communicating to the first portion of the chain-belt assembly. 16. High speed civil transport NASA Technical Reports Server (NTRS) 1991-01-01 This report discusses the design and marketability of a next generation supersonic transport. Apogee Aeronautics Corporation has designated its High Speed Civil Transport (HSCT): Supercruiser HS-8. Since the beginning of the Concorde era, the general consensus has been that the proper time for the introduction of a next generation Supersonic Transport (SST) would depend upon the technical advances made in the areas of propulsion (reduction in emissions) and material composites (stronger, lighter materials). It is believed by many in the aerospace industry that these beforementioned technical advances lie on the horizon. With this being the case, this is the proper time to begin the design phase for the next generation HSCT. The design objective for a HSCT was to develop an aircraft that would be capable of transporting at least 250 passengers with baggage at a distance of 5500 nmi. The supersonic Mach number is currently unspecified. In addition, the design had to be marketable, cost effective, and certifiable. To achieve this goal, technical advances in the current SST's must be made, especially in the areas of aerodynamics and propulsion. As a result of these required aerodynamic advances, several different supersonic design concepts were reviewed. 17. Wind Speed Perception and Risk PubMed Central Agdas, Duzgun; Webster, Gregory D.; Masters, Forrest J. 2012-01-01 Background How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human–wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. Method We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Results Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual–perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. Conclusion These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters. PMID:23226230 18. High-Speed Schlieren Movies of Decelerators at Supersonic Speeds NASA Technical Reports Server (NTRS) 1960-01-01 High-Speed Schlieren Movies of Decelerators at Supersonic Speeds. Tests were conducted on several types of porous parachutes, a paraglider, and a simulated retrorocket. Mach numbers ranged from 1.8-3.0, porosity from 20-80 percent, and camera speeds from 1680-3000 feet per second (fps) in trials with porous parachutes. Trials of reefed parachutes were conducted at Mach number 2.0 and reefing of 12-33 percent at camera speeds of 600 fps. A flexible parachute with an inflatable ring in the periphery of the canopy was tested at Reynolds number 750,000 per foot, Mach number 2.85, porosity of 28 percent, and camera speed of 36oo fps. A vortex-ring parachute was tested at Mach number 2.2 and camera speed of 3000 fps. The paraglider, with a sweepback of 45 degrees at an angle of attack of 45 degrees was tested at Mach number 2.65, drag coefficient of 0.200, and lift coefficient of 0.278 at a camera speed of 600 fps. A cold air jet exhausting upstream from the center of a bluff body was used to simulate a retrorocket. The free-stream Mach number was 2.0, free-stream dynamic pressure was 620 lb/sq ft, jet-exit static pressure ratio was 10.9, and camera speed was 600 fps. [Entire movie available on DVD from CASI as Doc ID 20070030973. Contact help@sti.nasa.gov 19. Models of Speed Discrimination NASA Technical Reports Server (NTRS) 1997-01-01 visual search for the detection of speed deviation. 2. Perception of moving objects. 3. Exploring the role of eye movements in various visual tasks. 20. Speed control for synchronous motors NASA Technical Reports Server (NTRS) Packard, H.; Schott, J. 1981-01-01 Feedback circuit controls fluctuations in speed of synchronous ac motor. Voltage proportional to phase angle is developed by phase detector, rectified, amplified, compared to threshold, and reapplied positively or negatively to motor excitation circuit. Speed control reduces wow and flutter of audio turntables and tape recorders, and enhances hunting in gyroscope motors. 1. Propeller speed and phase sensor NASA Technical Reports Server (NTRS) Collopy, Paul D. (Inventor); Bennett, George W. (Inventor) 1992-01-01 A speed and phase sensor counterrotates aircraft propellers. A toothed wheel is attached to each propeller, and the teeth trigger a sensor as they pass, producing a sequence of signals. From the sequence of signals, rotational speed of each propeller is computer based on time intervals between successive signals. The speed can be computed several times during one revolution, thus giving speed information which is highly up-to-date. Given that spacing between teeth may not be uniform, the signals produced may be nonuniform in time. Error coefficients are derived to correct for nonuniformities in the resulting signals, thus allowing accurate speed to be computed despite the spacing nonuniformities. Phase can be viewed as the relative rotational position of one propeller with respect to the other, but measured at a fixed time. Phase is computed from the signals. 2. The need for speed: global optic flow speed influences steering. PubMed Kountouriotis, Georgios K; Mole, Callum D; Merat, Natasha; Wilkie, Richard M 2016-05-01 How do animals follow demarcated paths? Different species are sensitive to optic flow and one control solution is to maintain the balance of flow symmetry across visual fields; however, it is unclear whether animals are sensitive to changes in asymmetries when steering along curved paths. Flow asymmetries can alter the global properties of flow (i.e. flow speed) which may also influence steering control. We tested humans steering curved paths in a virtual environment. The scene was manipulated so that the ground plane to either side of the demarcated path produced larger or smaller asymmetries in optic flow. Independent of asymmetries and the locomotor speed, the scene properties were altered to produce either faster or slower globally averaged flow speeds. Results showed that rather than being influenced by changes in flow asymmetry, steering responded to global flow speed. We conclude that the human brain performs global averaging of flow speed from across the scene and uses this signal as an input for steering control. This finding is surprising since the demarcated path provided sufficient information to steer, whereas global flow speed (by itself) did not. To explain these findings, existing models of steering must be modified to include a new perceptual variable: namely global optic flow speed. PMID:27293789 3. The need for speed: global optic flow speed influences steering PubMed Central Kountouriotis, Georgios K.; Mole, Callum D.; Merat, Natasha 2016-01-01 How do animals follow demarcated paths? Different species are sensitive to optic flow and one control solution is to maintain the balance of flow symmetry across visual fields; however, it is unclear whether animals are sensitive to changes in asymmetries when steering along curved paths. Flow asymmetries can alter the global properties of flow (i.e. flow speed) which may also influence steering control. We tested humans steering curved paths in a virtual environment. The scene was manipulated so that the ground plane to either side of the demarcated path produced larger or smaller asymmetries in optic flow. Independent of asymmetries and the locomotor speed, the scene properties were altered to produce either faster or slower globally averaged flow speeds. Results showed that rather than being influenced by changes in flow asymmetry, steering responded to global flow speed. We conclude that the human brain performs global averaging of flow speed from across the scene and uses this signal as an input for steering control. This finding is surprising since the demarcated path provided sufficient information to steer, whereas global flow speed (by itself) did not. To explain these findings, existing models of steering must be modified to include a new perceptual variable: namely global optic flow speed. PMID:27293789 4. Dynamic modeling of speed skiing NASA Astrophysics Data System (ADS) Catalfamo, R. S. 1997-12-01 The equations of motion that describe a skier descending a speed-skiing hill are solved both analytically and numerically. The model is shown to agree well with actual official results but only when the hill profile is considered. A sensitivity analysis reveals which parameters most affect the skier's exit speed. Other factors, such as scaling effects and wind gusts, are included to determine whether these need to be considered in official results. One surprising result is that, under certain conditions and hill profiles, maximum skier speed is attained prior to entry into the timing zone—thus bringing into question the optimum placement of the timing gates. 5. SEAL FOR HIGH SPEED CENTRIFUGE DOEpatents Skarstrom, C.W. 1957-12-17 A seal is described for a high speed centrifuge wherein the centrifugal force of rotation acts on the gasket to form a tight seal. The cylindrical rotating bowl of the centrifuge contains a closure member resting on a shoulder in the bowl wall having a lower surface containing bands of gasket material, parallel and adjacent to the cylinder wall. As the centrifuge speed increases, centrifugal force acts on the bands of gasket material forcing them in to a sealing contact against the cylinder wall. This arrangememt forms a simple and effective seal for high speed centrifuges, replacing more costly methods such as welding a closure in place. 6. Numerical wind speed simulation model SciTech Connect Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y. 1981-09-01 A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared. 7. Development of Air Speed Nozzles NASA Technical Reports Server (NTRS) Zahm, A F 1920-01-01 Report describes the development of a suitable speed nozzle for the first few thousand airplanes made by the United States during the recent war in Europe, and to furnish a basis for more mature instruments in the future. Requirements for the project were to provide a suitable pressure collector for aircraft speed meters and to develop a speed nozzle which would be waterproof, powerful, unaffected by slight pitch and yaw, rugged and easy to manufacture, and uniform in structure and reading, so as not to require individual calibration. 8. Maxometers (peak wind speed anemometers) NASA Technical Reports Server (NTRS) Kaufman, J. W.; Camp, D. W.; Turner, R. E. (Inventor) 1973-01-01 An instrument for measuring peak wind speeds under severe environmental conditions is described, comprising an elongated cylinder housed in an outer casing. The cylinder contains a piston attached to a longitudinally movable guided rod having a pressure disk mounted on one projecting end. Wind pressure against the pressure disk depresses the movable rod. When the wind reaches its maximum speed, the rod is locked by a ball clutch mechanism in the position of maximum inward movement. Thereafter maximum wind speed or pressure readings may be taken from calibrated indexing means. 9. Superplane! High Speed Civil Transport NASA Technical Reports Server (NTRS) 1998-01-01 The High Speed Civil Transport (HSCT). This light-hearted promotional piece explains what the HSCT 'Superplane' is and what advantages it will have over current aircraft. As envisioned, the HSCT is a next-generation supersonic (faster than the speed of sound) passenger jet that would fly 300 passengers at more than 1,500 miles per hour -- more than twice the speed of sound. It will cross the Pacific or Atlantic in less than half the time of modern subsonic jets, and at a ticket price less than 20 percent above comparable, slower flights 10. High-Speed Schlieren Movies of Decelerators at Supersonic Speeds NASA Technical Reports Server (NTRS) 1960-01-01 Tests were conducted on several types of porous parachutes, a paraglider, and a simulated retrorocket. Mach numbers ranged from 1.8-3.0, porosity from 20-80 percent, and camera speeds from 1680-3000 feet per second (fps) in trials with porous parachutes. Trials of reefed parachutes were conducted at Mach number 2.0 and reefing of 12-33 percent at camera speeds of 600 fps. A flexible parachute with an inflatable ring in the periphery of the canopy was tested at Reynolds number 750,000 per foot, Mach number 2.85, porosity of 28 percent, and camera speed of 36oo fps. A vortex-ring parachute was tested at Mach number 2.2 and camera speed of 3000 fps. The paraglider, with a sweepback of 45 degrees at an angle of attack of 45 degrees was tested at Mach number 2.65, drag coefficient of 0.200, and lift coefficient of 0.278 at a camera speed of 600 fps. A cold air jet exhausting upstream from the center of a bluff body was used to simulate a retrorocket. The free-stream Mach number was 2.0, free-stream dynamic pressure was 620 lb/sq ft, jet-exit static pressure ratio was 10.9, and camera speed was 600 fps. 11. Speed, road injury, and public health. PubMed Richter, Elihu D; Berman, Tamar; Friedman, Lee; Ben-David, Gerald 2006-01-01 We review milestones in the history of increases in speed limits and travel speeds ("speed creep") and risks for road deaths and injury. Reduced speed limits, speed-camera networks, and speed calming substantially reduce these tolls in absolute numbers-a trend that is apparent in the United Kingdom, Australia, France, and other countries, but not in the United States, which has raised speed limits and does not have speed-camera networks. Newtonian relationships between the fourth power of small increases or reductions in speed and large increases or reductions in deaths state the case for speed control. Speed adaptation and the interaction between speed and other determinants of injury risks, including congestion and countermeasures, enter into these relationships. Speed-camera networks and speed calming lead to large, sustainable, and highly cost-effective drops in road deaths and injuries and should target entire populations, not merely high-risk subgroups or situations. Yet, there are major barriers to preventive strategies based on the discovery that speed kills. Modal shifts from speed on roads to speed on rail, lower maximum vehicle speeds, and speed-camera networks are required for progress toward Vision Zero-the goal of no road deaths-through Killing Speed. The human cost of the delay in killing speed in the United States may be as high as 20,000 lives lost per year. PMID:16533112 12. Driving Speed vs Fuel Efficiency. ERIC Educational Resources Information Center Vest, Floyd 1980-01-01 A mathematical treatment of the relationship between driving speed and fuel efficiency is presented. The material involves applications of exponentials, logarithms, and elementary calculus, and is intended to be enrichment material for secondary and lower college mathematics classes. (MP) 13. High-speed Wind Tunnels NASA Technical Reports Server (NTRS) Ackeret, J 1936-01-01 Wind tunnel construction and design is discussed especially in relation to subsonic and supersonic speeds. Reynolds Numbers and the theory of compressible flows are also taken into consideration in designing new tunnels. 14. Animal evolution: trilobites on speed. PubMed Budd, Graham E 2013-10-01 A new study quantifies rates of morphological and molecular evolution for arthropods during the critical Cambrian explosion. Both morphological and molecular evolution are accelerated--but not so much to break any speed limits. PMID:24112983 15. High-Speed Electrochemical Imaging. PubMed Momotenko, Dmitry; Byers, Joshua C; McKelvey, Kim; Kang, Minkyung; Unwin, Patrick R 2015-09-22 The design, development, and application of high-speed scanning electrochemical probe microscopy is reported. The approach allows the acquisition of a series of high-resolution images (typically 1000 pixels μm(-2)) at rates approaching 4 seconds per frame, while collecting up to 8000 image pixels per second, about 1000 times faster than typical imaging speeds used up to now. The focus is on scanning electrochemical cell microscopy (SECCM), but the principles and practicalities are applicable to many electrochemical imaging methods. The versatility of the high-speed scan concept is demonstrated at a variety of substrates, including imaging the electroactivity of a patterned self-assembled monolayer on gold, visualization of chemical reactions occurring at single wall carbon nanotubes, and probing nanoscale electrocatalysts for water splitting. These studies provide movies of spatial variations of electrochemical fluxes as a function of potential and a platform for the further development of high speed scanning with other electrochemical imaging techniques. PMID:26267455 16. Dynamic Dazzle Distorts Speed Perception PubMed Central Hall, Joanna R.; Cuthill, Innes C.; Baddeley, Roland; Attwood, Angela S.; Munafò, Marcus R.; Scott-Samuel, Nicholas E. 2016-01-01 Static high contrast (‘dazzle’) patterns, such as zigzags, have been shown to reduce the perceived speed of an object. It has not escaped our notice that this effect has possible military applications and here we report a series of experiments on humans, designed to establish whether dynamic dazzle patterns can cause distortions of perceived speed sufficient to provide effective defence in the field, and the extent to which these effects are robust to a battery of manipulations. Dynamic stripe patterns moving in the same direction as the target are found to increase the perceived speed of that target, whilst dynamic stripes moving in the opposite direction to the target reduce the perceived speed. We establish the optimum position for such dazzle patches; confirm that reduced contrast and the addition of colour do not affect the performance of the dynamic dazzle, and finally, using the CO2 challenge, show that the effect is robust to stressful conditions. PMID:27196098 17. Gated high speed optical detector NASA Technical Reports Server (NTRS) Green, S. I.; Carson, L. M.; Neal, G. W. 1973-01-01 The design, fabrication, and test of two gated, high speed optical detectors for use in high speed digital laser communication links are discussed. The optical detectors used a dynamic crossed field photomultiplier and electronics including dc bias and RF drive circuits, automatic remote synchronization circuits, automatic gain control circuits, and threshold detection circuits. The equipment is used to detect binary encoded signals from a mode locked neodynium laser. 18. Speed Variance and Its Influence on Accidents. ERIC Educational Resources Information Center Garber, Nicholas J.; Gadirau, Ravi A study was conducted to investigate the traffic engineering factors that influence speed variance and to determine to what extent speed variance affects accident rates. Detailed analyses were carried out to relate speed variance with posted speed limit, design speeds, and other traffic variables. The major factor identified was the difference… 19. 36 CFR 4.21 - Speed limits. Code of Federal Regulations, 2014 CFR 2014-07-01 ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Speed limits. 4.21 Section 4... TRAFFIC SAFETY § 4.21 Speed limits. (a) Park area speed limits are as follows: (1) 15 miles per hour... superintendent may designate a different speed limit upon any park road when a speed limit set forth in... 20. 36 CFR 4.21 - Speed limits. Code of Federal Regulations, 2013 CFR 2013-07-01 ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Speed limits. 4.21 Section 4... TRAFFIC SAFETY § 4.21 Speed limits. (a) Park area speed limits are as follows: (1) 15 miles per hour... superintendent may designate a different speed limit upon any park road when a speed limit set forth in... 1. 36 CFR 4.21 - Speed limits. Code of Federal Regulations, 2012 CFR 2012-07-01 ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Speed limits. 4.21 Section 4... TRAFFIC SAFETY § 4.21 Speed limits. (a) Park area speed limits are as follows: (1) 15 miles per hour... superintendent may designate a different speed limit upon any park road when a speed limit set forth in... 2. 36 CFR 4.21 - Speed limits. Code of Federal Regulations, 2010 CFR 2010-07-01 ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Speed limits. 4.21 Section 4... TRAFFIC SAFETY § 4.21 Speed limits. (a) Park area speed limits are as follows: (1) 15 miles per hour... superintendent may designate a different speed limit upon any park road when a speed limit set forth in... 3. 36 CFR 4.21 - Speed limits. Code of Federal Regulations, 2011 CFR 2011-07-01 ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Speed limits. 4.21 Section 4... TRAFFIC SAFETY § 4.21 Speed limits. (a) Park area speed limits are as follows: (1) 15 miles per hour... superintendent may designate a different speed limit upon any park road when a speed limit set forth in... 4. 14 CFR 23.51 - Takeoff speeds. Code of Federal Regulations, 2010 CFR 2010-01-01 ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Takeoff speeds. 23.51 Section 23.51... speeds. (a) For normal, utility, and acrobatic category airplanes, rotation speed, VR, is the speed at... seaplanes and amphibians taking off from water, VR, may be any speed that is shown to be safe under... 5. 14 CFR 23.51 - Takeoff speeds. Code of Federal Regulations, 2011 CFR 2011-01-01 ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Takeoff speeds. 23.51 Section 23.51... speeds. (a) For normal, utility, and acrobatic category airplanes, rotation speed, VR, is the speed at... seaplanes and amphibians taking off from water, VR, may be any speed that is shown to be safe under... 6. Speed analyses of stimulus equivalence. PubMed Central Spencer, T J; Chase, P N 1996-01-01 The functional substitutability of stimuli in equivalence classes was examined through analyses of the speed of college students' accurate responding. After training subjects to respond to 18 conditional relations, subjects' accuracy and speed of accurate responding were compared across trial types (baseline, symmetry, transitivity, and combined transitivity and symmetry) and nodal distance (one- through five-node transitive and combined transitive and symmetric relations). Differences in accuracy across nodal distance and trial type were significant only on the first tests of equivalence, whereas differences in speed were significant even after extended testing. Response speed was inversely related to the number of nodes on which the tested relations were based. Significant differences in response speed were also found across trial types, except between transitivity and combined trials. To determine the generality of these comparisons, three groups of subjects were included: An instructed group was given an instruction that specified the interchangeability of stimuli related through training; a queried group was queried about the basis for test-trial responding: and a standard group was neither instructed nor queried. There were no significant differences among groups. These results suggest the use of response speed and response accuracy to measure the strength of matching relations. PMID:8636663 7. Combining Speed Information Across Space NASA Technical Reports Server (NTRS) Verghese, Preeti; Stone, Leland S. 1995-01-01 We used speed discrimination tasks to measure the ability of observers to combine speed information from multiple stimuli distributed across space. We compared speed discrimination thresholds in a classical discrimination paradigm to those in an uncertainty/search paradigm. Thresholds were measured using a temporal two-interval forced-choice design. In the discrimination paradigm, the n gratings in each interval all moved at the same speed and observers were asked to choose the interval with the faster gratings. Discrimination thresholds for this paradigm decreased as the number of gratings increased. This decrease was not due to increasing the effective stimulus area as a control experiment that increased the area of a single grating did not show a similar improvement in thresholds. Adding independent speed noise to each of the n gratings caused thresholds to decrease at a rate similar to the original no-noise case, consistent with observers combining an independent sample of speed from each grating in both the added- and no-noise cases. In the search paradigm, observers were asked to choose the interval in which one of the n gratings moved faster. Thresholds in this case increased with the number of gratings, behavior traditionally attributed to an input bottleneck. However, results from the discrimination paradigm showed that the increase was not due to observers' inability to process these gratings. We have also shown that the opposite trends of the data in the two paradigms can be predicted by a decision theory model that combines independent samples of speed information across space. This demonstrates that models typically used in classical detection and discrimination paradigms are also applicable to search paradigms. As our model does not distinguish between samples in space and time, it predicts that discrimination performance should be the same regardless of whether the gratings are presented in two spatial intervals or two temporal intervals. Our last 8. 49 CFR 230.68 - Speed indicators. Code of Federal Regulations, 2014 CFR 2014-10-01 ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Speed Indicators § 230.68 Speed indicators. Steam locomotives that operate at speeds in excess... 9. 49 CFR 230.68 - Speed indicators. Code of Federal Regulations, 2012 CFR 2012-10-01 ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Speed Indicators § 230.68 Speed indicators. Steam locomotives that operate at speeds in excess... 10. 49 CFR 230.68 - Speed indicators. Code of Federal Regulations, 2013 CFR 2013-10-01 ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Speed Indicators § 230.68 Speed indicators. Steam locomotives that operate at speeds in excess... 11. 36 CFR 1004.21 - Speed limits. Code of Federal Regulations, 2013 CFR 2013-07-01 ... traffic control devices. (c) Operating a vehicle at a speed in excess of the speed limit is prohibited. (d... of a vehicle on a Presidio Trust road. Signs indicating that vehicle speed is determined by the... 12. 36 CFR 1004.21 - Speed limits. Code of Federal Regulations, 2014 CFR 2014-07-01 ... traffic control devices. (c) Operating a vehicle at a speed in excess of the speed limit is prohibited. (d... of a vehicle on a Presidio Trust road. Signs indicating that vehicle speed is determined by the... 13. Low speed phaselock speed control system. [for brushless dc motor NASA Technical Reports Server (NTRS) Fulcher, R. W.; Sudey, J. (Inventor) 1975-01-01 A motor speed control system for an electronically commutated brushless dc motor is provided which includes a phaselock loop with bidirectional torque control for locking the frequency output of a high density encoder, responsive to actual speed conditions, to a reference frequency signal, corresponding to the desired speed. The system includes a phase comparator, which produces an output in accordance with the difference in phase between the reference and encoder frequency signals, and an integrator-digital-to-analog converter unit, which converts the comparator output into an analog error signal voltage. Compensation circuitry, including a biasing means, is provided to convert the analog error signal voltage to a bidirectional error signal voltage which is utilized by an absolute value amplifier, rotational decoder, power amplifier-commutators, and an arrangement of commutation circuitry. 14. Clinical Diagnoses before Age 75 and Men's Survival to Their 85th Birthday: The Manitoba Follow-Up Study ERIC Educational Resources Information Center Tate, Robert B.; Michaels, Leon; Cuddy, T. Edward; Bayomi, Dennis J. 2013-01-01 Purpose: Of all Canadian and American men who live to age 75 years, about half can expect to live to age 85. Our objective is to examine how clinical diagnoses made before age 75 relate to a man's survival to age 85 years. Design and Methods: Since 1948, a cohort of 3,983 young men (mean age of 31 years at entry) has been followed with routine… 15. Generalized Geometric Quantum Speed Limits NASA Astrophysics Data System (ADS) Pires, Diego Paiva; Cianciaruso, Marco; Céleri, Lucas C.; Adesso, Gerardo; Soares-Pinto, Diogo O. 2016-04-01 The attempt to gain a theoretical understanding of the concept of time in quantum mechanics has triggered significant progress towards the search for faster and more efficient quantum technologies. One of such advances consists in the interpretation of the time-energy uncertainty relations as lower bounds for the minimal evolution time between two distinguishable states of a quantum system, also known as quantum speed limits. We investigate how the nonuniqueness of a bona fide measure of distinguishability defined on the quantum-state space affects the quantum speed limits and can be exploited in order to derive improved bounds. Specifically, we establish an infinite family of quantum speed limits valid for unitary and nonunitary evolutions, based on an elegant information geometric formalism. Our work unifies and generalizes existing results on quantum speed limits and provides instances of novel bounds that are tighter than any established one based on the conventional quantum Fisher information. We illustrate our findings with relevant examples, demonstrating the importance of choosing different information metrics for open system dynamics, as well as clarifying the roles of classical populations versus quantum coherences, in the determination and saturation of the speed limits. Our results can find applications in the optimization and control of quantum technologies such as quantum computation and metrology, and might provide new insights in fundamental investigations of quantum thermodynamics. 16. Measuring Speeds with Microwave Interferometry NASA Astrophysics Data System (ADS) Hillberry, Logan 2014-03-01 The speed of an approximately frictionless cart is simultaneously measured in two ways. A 10.5 GHz microwave source is used in the familiar Michelson interferometry setup with one of the arms being the mobile cart and the other being a stationary microwave receiver. As the cart travels, the changing interference pattern is captured on an oscilloscope which, when combined with the source frequency, can be used to determine the cart's speed. The second speed measurement is achieved by sending a laser beam across the cart's path into a photo detector which is connected a second channel on the oscilloscope. The cart breaks the beam and travels a distance equal to its length before allowing the beam to reach the photo detector again. Using the oscilloscope's timing measurement and the known cart length, one can readily calculate the cart's speed. Comparison of the two methods conveys agreement within error, confirming the path length difference model used to calculate the speed of the cart in the microwave interferometry method. 17. Spatial layout affects speed discrimination NASA Technical Reports Server (NTRS) Verghese, P.; Stone, L. S. 1997-01-01 We address a surprising result in a previous study of speed discrimination with multiple moving gratings: discrimination thresholds decreased when the number of stimuli was increased, but remained unchanged when the area of a single stimulus was increased [Verghese & Stone (1995). Vision Research, 35, 2811-2823]. In this study, we manipulated the spatial- and phase relationship between multiple grating patches to determine their effect on speed discrimination thresholds. In a fusion experiment, we merged multiple stimulus patches, in stages, into a single patch. Thresholds increased as the patches were brought closer and their phase relationship was adjusted to be consistent with a single patch. Thresholds increased further still as these patches were fused into a single patch. In a fission experiment, we divided a single large patch into multiple patches by superimposing a cross with luminance equal to that of the background. Thresholds decreased as the large patch was divided into quadrants and decreased further as the quadrants were maximally separated. However, when the cross luminance was darker than the background, it was perceived as an occluder and thresholds, on average, were unchanged from that for the single large patch. A control experiment shows that the observed trend in discrimination thresholds is not due to the differences in perceived speed of the stimuli. These results suggest that the parsing of the visual image into entities affects the combination of speed information across space, and that each discrete entity effectively provides a single independent estimate of speed. 18. High speed laser tomography system. PubMed Samsonov, D; Elsaesser, A; Edwards, A; Thomas, H M; Morfill, G E 2008-03-01 A high speed laser tomography system was developed capable of acquiring three-dimensional (3D) images of optically thin clouds of moving micron-sized particles. It operates by parallel-shifting an illuminating laser sheet with a pair of galvanometer-driven mirrors and synchronously recording two-dimensional (2D) images of thin slices of the imaged volume. The maximum scanning speed achieved was 120,000 slices/s, sequences of 24 volume scans (up to 256 slices each) have been obtained. The 2D slices were stacked to form 3D images of the volume, then the positions of the particles were identified and followed in the consecutive scans. The system was used to image a complex plasma with particles moving at speeds up to cm/s. PMID:18377040 19. Speeding chemical reactions by focusing NASA Astrophysics Data System (ADS) Lacasta, A. M.; Ramírez-Piscina, L.; Sancho, J. M.; Lindenberg, K. 2013-04-01 We present numerical results for a chemical reaction of colloidal particles which are transported by a laminar fluid and are focused by periodic obstacles in such a way that the two components are well mixed and consequently the chemical reaction is speeded up. The roles of the various system parameters (diffusion coefficients, reaction rate, and obstacles sizes) are studied. We show that focusing speeds up the reaction from the diffusion limited rate ˜t-1/2 to very close to the perfect mixing rate, ˜t-1. 20. The speed of Galileon gravity NASA Astrophysics Data System (ADS) Brax, Philippe; Burrage, Clare; Davis, Anne-Christine 2016-03-01 We analyse the speed of gravitational waves in coupled Galileon models with an equation of state ωphi=-1 now and a ghost-free Minkowski limit. We find that the gravitational waves propagate much faster than the speed of light unless these models are small perturbations of cubic Galileons and the Galileon energy density is sub-dominant to a dominant cosmological constant. In this case, the binary pulsar bounds on the speed of gravitational waves can be satisfied and the equation of state can be close to -1 when the coupling to matter and the coefficient of the cubic term of the Galileon Lagrangian are related. This severely restricts the allowed cosmological behaviour of Galileon models and we are forced to conclude that Galileons with a stable Minkowski limit cannot account for the observed acceleration of the expansion of the universe on their own. Moreover any sub-dominant Galileon component of our universe must be dominated by the cubic term. For such models with gravitons propagating faster than the speed of light, the gravitons become potentially unstable and could decay into photon pairs. They could also emit photons by Cerenkov radiation. We show that the decay rate of such speedy gravitons into photons and the Cerenkov radiation are in fact negligible. Moreover the time delay between the gravitational signal and light emitted by explosive astrophysical events could serve as a confirmation that a modification of gravity acts on the largest scales of the Universe. 1. An inexpensive vehicle speed detector NASA Technical Reports Server (NTRS) Broussard, P., Jr. 1973-01-01 Low-power minicomputer can plug into automobile cigarette lighter. It measures time it takes observed car to travel premeasured distance and provides immediate readout of speed. Potentially, detector could be manufactured for less than$200 per unit and would have very low maintenance cost.

2. The Speeding Car Design Challenge

ERIC Educational Resources Information Center

Roman, Harry T.

2009-01-01

All too often, one reads about high-speed police chases in pursuit of stolen cars that result in death and injury to people and innocent bystanders. Isn't there another way to accomplish the apprehension of the thieves that does not put people at such great risk? This article presents a classroom challenge to use technology to remotely shutdown…

3. NASA low speed centrifugal compressor

NASA Technical Reports Server (NTRS)

Hathaway, Michael D.

1990-01-01

The flow characteristics of a low speed centrifugal compressor were examined at NASA Lewis Research Center to improve understanding of the flow in centrifugal compressors, to provide models of various flow phenomena, and to acquire benchmark data for three dimensional viscous flow code validation. The paper describes the objectives, test facilities' instrumentation, and experiment preliminary comparisons.

4. High speed multiwire photon camera

NASA Technical Reports Server (NTRS)

Lacy, Jeffrey L. (Inventor)

1991-01-01

An improved multiwire proportional counter camera having particular utility in the field of clinical nuclear medicine imaging. The detector utilizes direct coupled, low impedance, high speed delay lines, the segments of which are capacitor-inductor networks. A pile-up rejection test is provided to reject confused events otherwise caused by multiple ionization events occuring during the readout window.

5. High speed multiwire photon camera

NASA Technical Reports Server (NTRS)

Lacy, Jeffrey L. (Inventor)

1989-01-01

An improved multiwire proportional counter camera having particular utility in the field of clinical nuclear medicine imaging. The detector utilizes direct coupled, low impedance, high speed delay lines, the segments of which are capacitor-inductor networks. A pile-up rejection test is provided to reject confused events otherwise caused by multiple ionization events occurring during the readout window.

6. Cloud shadow Speed Sensor (CSS)

Fung, Victor

Changing cloud cover is a major source of solar radiation variability and poses challenges for the integration of solar energy. A compact and economical system that measures cloud shadow motion vectors to estimate power plant ramp rates and provide short-term forecasting is presented. The Cloud shadow Speed Sensor (CSS) is constructed using an array of luminance sensors and a high-speed data acquisition system to resolve the progression of cloud passages across the sensor footprint. An embedded microcontroller acquires the sensor data and uses a cross-correlation algorithm to determine cloud shadow motion vectors. The CSS was validated against an artificial shading test apparatus, an alternative method of cloud motion detection from ground-measured irradiance (linear cloud edge, LCE), and a UC San Diego sky imager (USI). The CSS detected artificial shadow directions and speeds to within 15° and 6 % accuracy, respectively. The CSS detected (real) cloud shadow directions and speeds with average weighted root-mean-square difference of 22° and 1.9 m s-1 when compared to USI and 33° and 1.5 m s -1 when compared to LCE results.

7. Algebra 1's Speed Trap

ERIC Educational Resources Information Center

Gupta, Neil Kenneth

2004-01-01

Students often look for real-life situations where they can apply the concepts they learn. A project of measuring the speed of moving cars demonstrates that they learn communication skills, teamwork skills, and develop patience specially when work in a group with a common purpose.

8. The Art Speed of Light

Wojcik, Jan

2006-03-01

The Roman poet Horace predicted correctly his phrase aere perennius, would last longer than bronze'' because the Ode he wrote travels to the eye at nearly the speed of light regardless of the rate of the decay of the paper it's written on. John Keats's 19th century Ode predicted correctly the youthful figures he saw on a bronze age Grecian Urn moved in slow time'' aging little from the time of painting to the time of his viewing in the British museum-and to ours today of the same urn. The youthful images of the Keystone Kops have aged slower than their twins-- their mortal actors. Discoveries about light's speed occurred synchronously with the engineering of telegraph and radio transmissions in the 19th century-which allowed anyone an experience of what Physics had discovered. Einstein's privotal papers appeared in the same year as the first feature film shot and transmitted at the speed of light regardless of the aging of the film stock. Experiencing the light-like speed of art in Keat's ode, Cubism, Bob and Ray's radio, the Keystone Kops provides an aesthetic, visceral understanding of Einstein's Twin's Paradox about the dilation of time.

9. Speed Judgements of Transparent Stimuli

NASA Technical Reports Server (NTRS)

Mulligan, Jeffrey B.; Null, Cynthia H. (Technical Monitor)

1996-01-01

10. Low Speed Control for Automatic Welding

NASA Technical Reports Server (NTRS)

Iceland, W. E.

1982-01-01

Amplifier module allows rotating positioner of automatic welding machine to operate at speeds below normal range. Low speeds are precisely regulated by a servomechanism as are normal-range speeds. Addition of module to standard welding machine makes it unnecessary to purchase new equipment for low-speed welding.

11. 14 CFR 27.1509 - Rotor speed.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor speed. 27.1509 Section 27.1509... Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

12. 14 CFR 25.1507 - Maneuvering speed.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

13. 14 CFR 25.1507 - Maneuvering speed.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

14. 14 CFR 29.1509 - Rotor speed.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor speed. 29.1509 Section 29.1509....1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

15. 14 CFR 27.1509 - Rotor speed.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Rotor speed. 27.1509 Section 27.1509... Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

16. 14 CFR 27.1509 - Rotor speed.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor speed. 27.1509 Section 27.1509... Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

17. 14 CFR 91.117 - Aircraft speed.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Aircraft speed. 91.117 Section 91.117... speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10... than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed....

18. 14 CFR 23.49 - Stalling speed.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Stalling speed. 23.49 Section 23.49... speed. (a) VSO (maximum landing flap configuration) and VS1 are the stalling speeds or the minimum steady flight speeds, in knots (CAS), at which the airplane is controllable with— (1) For...

19. 14 CFR 91.117 - Aircraft speed.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Aircraft speed. 91.117 Section 91.117... speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10... than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed....

20. 14 CFR 23.49 - Stalling speed.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Stalling speed. 23.49 Section 23.49... speed. (a) VSO (maximum landing flap configuration) and VS1 are the stalling speeds or the minimum steady flight speeds, in knots (CAS), at which the airplane is controllable with— (1) For...

1. 14 CFR 29.1509 - Rotor speed.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Rotor speed. 29.1509 Section 29.1509....1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

2. 14 CFR 25.1507 - Maneuvering speed.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

3. 14 CFR 29.1509 - Rotor speed.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Rotor speed. 29.1509 Section 29.1509....1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

4. 14 CFR 91.117 - Aircraft speed.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Aircraft speed. 91.117 Section 91.117... speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10... than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed....

5. Faster Is Better: High-Speed Modems.

ERIC Educational Resources Information Center

Roth, Cliff

1995-01-01

Discusses using high-speed modems to access the Internet. Examines internal and external modems, data speeds, compression and error reduction, faxing and voice capabilities, and software features. Considers ISDN (Integrated Services Digital Network) as the future replacement of high-speed modems. Sidebars present high-speed modem product…

6. 14 CFR 27.1509 - Rotor speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor speed. 27.1509 Section 27.1509... Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

7. 49 CFR 230.68 - Speed indicators.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Speed indicators. 230.68 Section 230.68... Tenders Speed Indicators § 230.68 Speed indicators. Steam locomotives that operate at speeds in excess of 20 miles per hour over the general system of railroad transportation shall be equipped with...

8. 14 CFR 91.117 - Aircraft speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Aircraft speed. 91.117 Section 91.117... speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10... than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed....

9. 14 CFR 29.1509 - Rotor speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Rotor speed. 29.1509 Section 29.1509....1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

10. 49 CFR 229.117 - Speed indicators.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Speed indicators. 229.117 Section 229.117... § 229.117 Speed indicators. (a) After December 31, 1980, each locomotive used as a controlling locomotive at speeds in excess of 20 miles per hour shall be equipped with a speed indicator which is—...

11. 14 CFR 91.117 - Aircraft speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Aircraft speed. 91.117 Section 91.117... speed. (a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10... than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed....

12. 14 CFR 25.1507 - Maneuvering speed.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

13. 49 CFR 230.68 - Speed indicators.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Speed indicators. 230.68 Section 230.68... Tenders Speed Indicators § 230.68 Speed indicators. Steam locomotives that operate at speeds in excess of 20 miles per hour over the general system of railroad transportation shall be equipped with...

14. 14 CFR 27.1509 - Rotor speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor speed. 27.1509 Section 27.1509... Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be established... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

15. 14 CFR 25.1507 - Maneuvering speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Maneuvering speed. 25.1507 Section 25.1507....1507 Maneuvering speed. The maneuvering speed must be established so that it does not exceed the design maneuvering speed V A determined under § 25.335(c)....

16. 49 CFR 229.117 - Speed indicators.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Speed indicators. 229.117 Section 229.117... § 229.117 Speed indicators. (a) After December 31, 1980, each locomotive used as a controlling locomotive at speeds in excess of 20 miles per hour shall be equipped with a speed indicator which is—...

17. 14 CFR 29.1509 - Rotor speed.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Rotor speed. 29.1509 Section 29.1509....1509 Rotor speed. (a) Maximum power-off (autorotation). The maximum power-off rotor speed must be... minimum power-off rotor speed must be established so that it is not less than 105 percent of the...

18. Driver views on speed and enforcement.

PubMed

Schechtman, Edna; Bar-Gera, Hillel; Musicant, Oren

2016-04-01

This paper reports on the results of a drivers' survey regarding the effects of speed cameras for speed enforcement in Israel. The survey was part of a larger study that accompanied the introduction of digital speed cameras. Speed camera deployment started in 2011, and till the end of 2013 twenty-one cameras were deployed in interurban road sections. Yearly surveys were taken between 2010 and 2013 in 9 gas stations near speed camera installation sites in order to capture drivers' opinions about speed and enforcement. Overall, 1993 drivers were interviewed. In terms of admitted speed behavior, 38% of the drivers in 2010, 21% in 2011, 13% in 2012 and 11% in 2013 reported that their driving speed was above the perceived posted speed limit. The proportion of drivers indicating some speed camera influence on driving decreased over the years. In addition, the majority of drivers (61%) predicted positive impact of speed cameras on safety. This result did not change significantly over the years. The main stated explanation for speed limit violations was time pressure, while the main stated explanation for respecting the posted speed was enforcement, rather than safety concerns. Linear regression and sigmoidal models were applied to describe the linkage between the reported driving speed (dependent) and the perceived posted speed (independent). The sigmoidal model fitted the data better, especially at high levels of the perceived posted speeds. That is, although the perceived posted speed increased, at some point the actual driving speed levels off (asymptote) and did not increase. Moreover, we found that the upper asymptote of the sigmoidal model decreased over the years: from 113.22 (SE=18.84)km/h in 2010 to 88.92 (SE=1.55)km/h in 2013. A wide variance in perceived speed limits suggest that drivers may not know what the speed limits really are. PMID:26773696

19. Circuit Regulates Speed Of dc Motor

NASA Technical Reports Server (NTRS)

Weaver, Charles; Padden, Robin; Brown, Floyd A., Jr.

1990-01-01

Driving circuit regulates speed of small dc permanent-magnet motor in tape recorder. Two nested feedback loops maintain speed within 1 percent of constant value. Inner loop provides coarse regulation, while outer loop removes most of variation in speed that remains in the presence of regulation by the inner loop. Compares speed of motor with commanded speed and adjusts current supplied to motor accordingly.

20. Closed-Loop Motor-Speed Control

NASA Technical Reports Server (NTRS)

Smith, Matthew A.; Delcher, Ray C.; Huston, Steven W.

1989-01-01

Electronic motor-speed control circuit designed to operate in electrically noisy environment. Includes optoelectronic pick-up device, placed inside motor housing to provide speed feedback signal. Automatically maintains speed motor at commanded value. Measures speed of motor in terms of frequency of pulses of infrared light chopped by fan blades of motor. Difference between measured and commanded speeds serves as control signal for external amplifier driving motor. Major advantage of circuit is low cost.

1. The effects of fructose-containing sugars on weight, body composition and cardiometabolic risk factors when consumed at up to the 90th percentile population consumption level for fructose.

PubMed

Lowndes, Joshua; Sinnett, Stephanie; Yu, Zhiping; Rippe, James

2014-08-01

The American Heart Association (AHA) and World Health Organization (WHO) have recommended restricting calories from added sugars at lower levels than the Institute of Medicine (IOM) recommendations, which are incorporated in the Dietary Guidelines for Americans 2010 (DGAs 2010). Sucrose (SUC) and high fructose corn syrup (HFCS) have been singled out for particular concern, because of their fructose content, which has been specifically implicated for its atherogenic potential and possible role in elevating blood pressure through uric acid-mediated endothelial dysfunction. This study explored the effects when these sugars are consumed at typical population levels up to the 90th percentile population consumption level for fructose. Three hundred fifty five overweight or obese individuals aged 20-60 years old were placed on a eucaloric diet for 10 weeks, which incorporated SUC- or HFCS-sweetened, low-fat milk at 8%, 18% or 30% of calories. There was a slight change in body weight in the entire cohort (169.1 ± 30.6 vs. 171.6 ± 31.8 lbs, p < 0.01), a decrease in HDL (52.9 ± 12.2 vs. 52.0 ± 13.9 mg/dL, p < 0.05) and an increase in triglycerides (104.1 ± 51.8 vs. 114.1 ± 64.7 mg/dL, p < 0.001). However, total cholesterol (183.5 ± 42.8 vs. 184.4 mg/dL, p > 0.05), LDL (110.3 ± 32.0 vs. 110.5 ± 38.9 mg/dL, p > 0.05), SBP (109.4 ± 10.9 vs. 108.3 ± 10.9 mmHg, p > 0.05) and DBP (72.1 ± 8.0 vs. 71.3 ± 8.0 mmHg, p > 0.05) were all unchanged. In no instance did the amount or type of sugar consumed affect the response to the intervention (interaction p > 0.05). These data suggest that: (1) when consumed as part of a normal diet, common fructose-containing sugars do not raise blood pressure, even when consumed at the 90th percentile population consumption level for fructose (five times the upper level recommended by the AHA and three times the upper level recommended by WHO); (2) changes in the lipid profile are mixed, but modest. PMID:25111121

2. HIPPI-6400 -- Designing for speed

SciTech Connect

Tolmie, D.E.

1998-03-01

The emerging High Performance Parallel Interface 6400 Mbit/s interface (HIPPI-6400), is targeted as a local area network (LAN), or system area network (SAN), supporting data rates of 6400 Mbit/s (800 Mbyte/s). This is eight times the speed of Gigabit Ethernet. The features used, and the design choices made, for the data link and physical layers of HIPPI-6400, to achieve this unprecedented speed are the subject of this paper. HIPPI-6400 borrowed freely from other successful technologies such as ATM, Ethernet and the original HIPPI -- taking the best features of each and melding them with some new features. HIPPI-6400 is a cost effective reliable interconnect for distances up to 1 km; it intermixes large and small messages efficiently.

3. Slow-Slip Propagation Speeds

Rubin, A. M.; Ampuero, J.

2007-12-01

Combined seismic and geodetic data from subduction zones and the Salton Trough have revealed slow slip events with reasonably well-defined propagation speeds. This in turn is suggestive of a more-or-less well- defined front separating nearly locked regions outside the slipping zone from interior regions that slide much more rapidly. Such crack-like nucleation fronts arise naturally in models of rate-and-state friction for lab-like values of a/b, where a and b are the coefficients of the velocity- and state-dependence of the frictional strength (with the surface being velocity-neutral for a/b=1). If the propagating front has a quasi-steady shape, the propagation and slip speeds are kinematically tied via the local slip gradient. Given a sufficiently sharp front, the slip gradient is given dimensionally by Δτp- r/μ', where Δτp-r is the peak-to-residual stress drop at the front and μ' the effective elastic shear modulus. Rate-and-state simulations indicate that Δτp-r is given reasonably accurately by bσ\\ln(Vmaxθi/Dc), where σ is the effective normal stress, Vmax is the maximum slip speed behind the propagating front, θi is the the value of "state" ahead of the propagating front, and Dc is the characteristic slip distance for state evolution. Except for a coefficient of order unity, Δτp-r is independent of the evolution law. This leads to Vprop/Vmax ~μ'/[bσ\\ln(Vmaxθi/Dc)]. For slip speeds a few orders of magnitude above background, \\ln(Vmaxθi/Dc) can with reasonable accuracy be assigned some representative value (~4-5, for example). Subduction zone transients propagate on the order of 10 km/day or 10-1 m/s. Geodetic data constrain the average slip speed to be a few times smaller than 1 cm/day or 10-7 m/s. However, numerical models indicate that the maximum slip speed at the front may be several times larger than the average, over a length scale that is probably too small to resolve geodetically, so a representative value of Vprop/Vmax may be ~106

4. Experiments on high speed ejectors

NASA Technical Reports Server (NTRS)

Wu, J. J.

1986-01-01

Experimental studies were conducted to investigate the flow and the performance of thrust augmenting ejectors for flight Mach numbers in the range of 0.5 to 0.8, primary air stagnation pressures up to 107 psig (738 kPa), and primary air stagnation temperatures up to 1250 F (677 C). The experiment verified the existence of the second solution ejector flow, where the flow after complete mixing is supersonic. Thrust augmentation in excess of 1.2 was demonstrated for both hot and cold primary jets. The experimental ejector performed better than the corresponding theoretical optimal first solution ejector, where the mixed flow is subsonic. Further studies are required to realize the full potential of the second solution ejector. The research program was started by the Flight Dynamics Research Corporation (FDRC) to investigate the characteristic of a high speed ejector which augments thrust of a jet at high flight speeds.

5. Small Scale High Speed Turbomachinery

NASA Technical Reports Server (NTRS)

London, Adam P. (Inventor); Droppers, Lloyd J. (Inventor); Lehman, Matthew K. (Inventor); Mehra, Amitav (Inventor)

2015-01-01

A small scale, high speed turbomachine is described, as well as a process for manufacturing the turbomachine. The turbomachine is manufactured by diffusion bonding stacked sheets of metal foil, each of which has been pre-formed to correspond to a cross section of the turbomachine structure. The turbomachines include rotating elements as well as static structures. Using this process, turbomachines may be manufactured with rotating elements that have outer diameters of less than four inches in size, and/or blading heights of less than 0.1 inches. The rotating elements of the turbomachines are capable of rotating at speeds in excess of 150 feet per second. In addition, cooling features may be added internally to blading to facilitate cooling in high temperature operations.

6. Variable-Speed Instrumented Centrifuges

NASA Technical Reports Server (NTRS)

Chapman, David K.; Brown, Allan H.

1991-01-01

Report describes conceptual pair of centrifuges, speed of which varied to produce range of artificial gravities in zero-gravity environment. Image and data recording and controlled temperature and gravity provided for 12 experiments. Microprocessor-controlled centrifuges include video cameras to record stop-motion images of experiments. Potential applications include studies of effect of gravity on growth and on production of hormones in corn seedlings, experiments with magnetic flotation to separate cells, and electrophoresis to separate large fragments of deoxyribonucleic acid.

7. Vortex Flows at Supersonic Speeds

NASA Technical Reports Server (NTRS)

Wood, Richard M.; Wilcox, Floyd J., Jr.; Bauer, Steven X. S.; Allen, Jerry M.

2003-01-01

A review of research conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) into high-speed vortex flows during the 1970s, 1980s, and 1990s is presented. The data are for flat plates, cavities, bodies, missiles, wings, and aircraft with Mach numbers of 1.5 to 4.6. Data are presented to show the types of vortex structures that occur at supersonic speeds and the impact of these flow structures on vehicle performance and control. The data show the presence of both small- and large-scale vortex structures for a variety of vehicles, from missiles to transports. For cavities, the data show very complex multiple vortex structures exist at all combinations of cavity depth to length ratios and Mach number. The data for missiles show the existence of very strong interference effects between body and/or fin vortices. Data are shown that highlight the effect of leading-edge sweep, leading-edge bluntness, wing thickness, location of maximum thickness, and camber on the aerodynamics of and flow over delta wings. Finally, a discussion of a design approach for wings that use vortex flows for improved aerodynamic performance at supersonic speeds is presented.

8. High speed nano-metrology

SciTech Connect

Humphris, Andrew D. L.; Zhao Bin; Catto, David; Kohli, Priyanka; Howard-Knight, Jeremy P.; Hobbs, Jamie K.

2011-04-15

For manufacturing at the nanometre scale a method for rapid and accurate measurement of the resultant functional devices is required. Although atomic force microscopy (AFM) has the requisite spatial resolution, it is severely limited in scan speed, the resolution and repeatability of vertical and lateral measurements being degraded when speed is increased. Here we present a new approach to AFM that makes a direct and feedback-independent measurement of surface height using a laser interferometer focused onto the back of the AFM tip. Combining this direct height measurement with a passive, feedback-free method for maintaining tip-sample contact removes the constraint on scan speed that comes from the bandwidth of the z-feedback loop. Conventional laser reflection detection is used for feedback control, which now plays the role of minimising tip-sample forces, rather than producing the sample topography. Using the system in conjunction with a rapid scanner, true height images are obtained with areas up to (36 x 36) {mu}m{sup 2} at 1 image/second, suitable for in-line applications.

9. Quiet High-Speed Fan

NASA Technical Reports Server (NTRS)

Lieber, Lysbeth; Repp, Russ; Weir, Donald S.

1996-01-01

A calibration of the acoustic and aerodynamic prediction methods was performed and a baseline fan definition was established and evaluated to support the quiet high speed fan program. A computational fluid dynamic analysis of the NASA QF-12 Fan rotor, using the DAWES flow simulation program was performed to demonstrate and verify the causes of the relatively poor aerodynamic performance observed during the fan test. In addition, the rotor flowfield characteristics were qualitatively compared to the acoustic measurements to identify the key acoustic characteristics of the flow. The V072 turbofan source noise prediction code was used to generate noise predictions for the TFE731-60 fan at three operating conditions and compared to experimental data. V072 results were also used in the Acoustic Radiation Code to generate far field noise for the TFE731-60 nacelle at three speed points for the blade passage tone. A full 3-D viscous flow simulation of the current production TFE731-60 fan rotor was performed with the DAWES flow analysis program. The DAWES analysis was used to estimate the onset of multiple pure tone noise, based on predictions of inlet shock position as a function of the rotor tip speed. Finally, the TFE731-60 fan rotor wake structure predicted by the DAWES program was used to define a redesigned stator with the leading edge configured to minimize the acoustic effects of rotor wake / stator interaction, without appreciably degrading performance.

10. Healthy Eating in Out-of-School Time: The Promise and the Challenge

ERIC Educational Resources Information Center

Wiecha, Jean L.; Hall, Georgia; Gannett, Ellen; Roth, Barbara

2012-01-01

More than 30 percent of American children are either overweight or obese, with a body mass index (BMI) in the 85th percentile or above. Although prevalence varies by age, sex, and ethnicity, all groups are affected. Risk of serious health problems increases with increasing BMI. Childhood obesity, characterized by BMI in the 95th percentile or…

11. Percentage of Children with a Healthy Weight

MedlinePlus

... e. not age-adjusted) of civilian, non-institutionalized population are provided. Healthy BMI for children: A BMI greater than or equal to the 5th percentile and less than the 85th percentile of sex specific CDC growth charts. BMI: Body mass index, which is equal ...

12. The President's Challenge Physical Fitness Program Packet, 1997-98.

ERIC Educational Resources Information Center

President's Council on Physical Fitness and Sports, Washington, DC.

The President's Challenge Physical Fitness Awards Program makes four awards: The Presidential Physical Fitness Award recognizes those students who score at or about the 85th percentile on all five tests; the National Physical Fitness Award for those in the 50th to 84th percentile; the Participant Award for those who fall below the 50th percentile…

13. Dual-speed wind turbine generation

SciTech Connect

Muljadi, E.; Butterfield, C.P.; Handman, D.

1996-10-01

Induction generator has been used since the early development of utility-scale wind turbine generation. An induction generator is the generator of choice because of its ruggedness and low cost. With an induction generator, the operating speed of the wind turbine is limited to a narrow range (almost constant speed). Dual- speed operation can be accomplished by using an induction generator with two different sets of winding configurations or by using a dual output drive train to drive two induction generators with two different rated speeds. With single-speed operation, the wind turbine operates at different power coefficients (Cp) as the wind speed varies. Operation at maximum Cp can occur only at a single wind speed. However, if the wind speed.varies across a wider range, the operating Cp will vary significantly. Dual-speed operation has the advantage of enabling the wind turbine to operate at near maximum Cp over a wider range of wind speeds. Thus, annual energy production can be increased. The dual-speed mode may generate less energy than a variable-speed mode; nevertheless, it offers an alternative which captures more energy than single-speed operation. In this paper, dual-speed operation of a wind turbine is investigated. Annual energy production is compared between single-speed and dual-speed operation. One type of control algorithm for dual-speed operation is proposed. Some results from a dynamic simulation will be presented to show how the control algorithm works as the wind turbine is exposed to varying wind speeds.

14. Systems and methods for vehicle speed management

DOEpatents

Sujan, Vivek Anand; Vajapeyazula, Phani; Follen, Kenneth; Wu, An; Forst, Howard Robert

2016-03-01

Controlling a speed of a vehicle based on at least a portion of a route grade and a route distance divided into a plurality of route sections, each including at least one of a section grade and section length. Controlling the speed of the vehicle is further based on determining a cruise control speed mode for the vehicle for each of the plurality of route sections and determining a speed reference command of the vehicle based on at least one of the cruise control speed mode, the section length, the section grade, and a current speed.

15. Speed control with end cushion for high speed air cylinder

DOEpatents

Stevens, Wayne W.; Solbrig, Charles W.

1991-01-01

A high speed air cylinder in which the longitudinal movement of the piston within the air cylinder tube is controlled by pressurizing the air cylinder tube on the accelerating side of the piston and releasing pressure at a controlled rate on the decelerating side of the piston. The invention also includes a method for determining the pressure required on both the accelerating and decelerating sides of the piston to move the piston with a given load through a predetermined distance at the desired velocity, bringing the piston to rest safely without piston bounce at the end of its complete stroke.

16. Early life cognitive abilities and body weight: cross-sectional study of the association of inhibitory control, cognitive flexibility, and sustained attention with BMI percentiles in primary school children.

PubMed

Wirt, Tamara; Schreiber, Anja; Kesztyüs, Dorothea; Steinacker, Jürgen M

2015-01-01

The objective of this study was to investigate the association of different cognitive abilities with children's body weight adjusted for further weight influencing sociodemographic, family, and lifestyle factors. Cross-sectional data of 498 primary school children (7.0 ± 0.6 years; 49.8% boys) participating in a health promotion programme in southwest Germany were used. Children performed a computer-based test battery (KiTAP) including an inhibitory control task (Go-Nogo paradigm), a cognitive flexibility task, and a sustained attention task. Height and weight were measured in a standardized manner and converted to BMI percentiles based on national standards. Sociodemographic features (migration background and parental education), family characteristics (parental body weight), and children's lifestyle (TV consumption, physical activity, consumption of sugar-sweetened beverages and breakfast habits) were assessed via parental questionnaire. A hierarchical regression analysis revealed inhibitory control and cognitive flexibility to be significant cognitive predictors for children's body weight. There was no association concerning sustained attention. The findings suggest that especially cognitive abilities known as executive functions (inhibitory control and cognitive flexibility) are associated with children's body weight. Future longitudinal and intervention studies are necessary to investigate the directionality of the association and the potential of integrating cognitive training in obesity prevention strategies. This trial is registered with ClinicalTrials.gov DRKS00000494. PMID:25874122

17. Early Life Cognitive Abilities and Body Weight: Cross-Sectional Study of the Association of Inhibitory Control, Cognitive Flexibility, and Sustained Attention with BMI Percentiles in Primary School Children

PubMed Central

Wirt, Tamara; Schreiber, Anja; Kesztyüs, Dorothea; Steinacker, Jürgen M.

2015-01-01

The objective of this study was to investigate the association of different cognitive abilities with children's body weight adjusted for further weight influencing sociodemographic, family, and lifestyle factors. Cross-sectional data of 498 primary school children (7.0 ± 0.6 years; 49.8% boys) participating in a health promotion programme in southwest Germany were used. Children performed a computer-based test battery (KiTAP) including an inhibitory control task (Go-Nogo paradigm), a cognitive flexibility task, and a sustained attention task. Height and weight were measured in a standardized manner and converted to BMI percentiles based on national standards. Sociodemographic features (migration background and parental education), family characteristics (parental body weight), and children's lifestyle (TV consumption, physical activity, consumption of sugar-sweetened beverages and breakfast habits) were assessed via parental questionnaire. A hierarchical regression analysis revealed inhibitory control and cognitive flexibility to be significant cognitive predictors for children's body weight. There was no association concerning sustained attention. The findings suggest that especially cognitive abilities known as executive functions (inhibitory control and cognitive flexibility) are associated with children's body weight. Future longitudinal and intervention studies are necessary to investigate the directionality of the association and the potential of integrating cognitive training in obesity prevention strategies. This trial is registered with ClinicalTrials.gov DRKS00000494. PMID:25874122

18. Abdominal Organ Location, Morphology, and Rib Coverage for the 5th, 50th, and 95th Percentile Males and Females in the Supine and Seated Posture using Multi-Modality Imaging

PubMed Central

Hayes, Ashley R.; Gayzik, F. Scott; Moreno, Daniel P.; Martin, R. Shayn; Stitzel, Joel D.

2013-01-01

The purpose of this study was to use data from a multi-modality image set of males and females representing the 5th, 50th, and 95th percentile (n=6) to examine abdominal organ location, morphology, and rib coverage variations between supine and seated postures. Medical images were acquired from volunteers in three image modalities including Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and upright MRI (uMRI). A manual and semi-automated segmentation method was used to acquire data and a registration technique was employed to conduct a comparative analysis between abdominal organs (liver, spleen, and kidneys) in both postures. Location of abdominal organs, defined by center of gravity movement, varied between postures and was found to be significant (p=0.002 to p=0.04) in multiple directions for each organ. In addition, morphology changes, including compression and expansion, were seen in each organ as a result of postural changes. Rib coverage, defined as the projected area of the ribs onto the abdominal organs, was measured in frontal, lateral, and posterior projections, and also varied between postures. A significant change in rib coverage between postures was measured for the spleen and right kidney (p=0.03 and p=0.02). The results indicate that posture affects the location, morphology and rib coverage area of abdominal organs and these implications should be noted in computational modeling efforts focused on a seated posture. PMID:24406951

19. Speed limits, enforcement, and health consequences.

PubMed

Elvik, Rune

2012-04-01

This review summarizes current knowledge regarding the effects of speed limit enforcement on public health. Speed limits are commonly used around the world to regulate the maximum speed at which motor vehicles can be operated on public roads. Speed limits are statutory, and violations of them are normally sanctioned by means of fixed penalties (traffic tickets) or, in the event of serious violations, suspension of the driver's license and imposition of prison sentences. Speed limit violations are widespread in all countries for which statistics can be found. Speeding contributes more to the risk of traffic injury than do other risk factors for which estimates of population-attributable risk are available. Traffic speed strongly influences impact speed in crashes and therefore has major implications for public health. PMID:22224882

20. Flexible high-speed CODEC

NASA Technical Reports Server (NTRS)

Segallis, Greg P.; Wernlund, Jim V.; Corry, Glen

1993-01-01

This report is prepared by Harris Government Communication Systems Division for NASA Lewis Research Center under contract NAS3-25087. It is written in accordance with SOW section 4.0 (d) as detailed in section 2.6. The purpose of this document is to provide a summary of the program, performance results and analysis, and a technical assessment. The purpose of this program was to develop a flexible, high-speed CODEC that provides substantial coding gain while maintaining bandwidth efficiency for use in both continuous and bursted data environments for a variety of applications.

1. Speeding up local correlation methods

Kats, Daniel

2014-12-01

We present two techniques that can substantially speed up the local correlation methods. The first one allows one to avoid the expensive transformation of the electron-repulsion integrals from atomic orbitals to virtual space. The second one introduces an algorithm for the residual equations in the local perturbative treatment that, in contrast to the standard scheme, does not require holding the amplitudes or residuals in memory. It is shown that even an interpreter-based implementation of the proposed algorithm in the context of local MP2 method is faster and requires less memory than the highly optimized variants of conventional algorithms.

2. Speeding up local correlation methods

SciTech Connect

Kats, Daniel

2014-12-28

We present two techniques that can substantially speed up the local correlation methods. The first one allows one to avoid the expensive transformation of the electron-repulsion integrals from atomic orbitals to virtual space. The second one introduces an algorithm for the residual equations in the local perturbative treatment that, in contrast to the standard scheme, does not require holding the amplitudes or residuals in memory. It is shown that even an interpreter-based implementation of the proposed algorithm in the context of local MP2 method is faster and requires less memory than the highly optimized variants of conventional algorithms.

3. High speed quantitative digital microscopy

NASA Technical Reports Server (NTRS)

Castleman, K. R.; Price, K. H.; Eskenazi, R.; Ovadya, M. M.; Navon, M. A.

1984-01-01

Modern digital image processing hardware makes possible quantitative analysis of microscope images at high speed. This paper describes an application to automatic screening for cervical cancer. The system uses twelve MC6809 microprocessors arranged in a pipeline multiprocessor configuration. Each processor executes one part of the algorithm on each cell image as it passes through the pipeline. Each processor communicates with its upstream and downstream neighbors via shared two-port memory. Thus no time is devoted to input-output operations as such. This configuration is expected to be at least ten times faster than previous systems.

4. High-Speed TCP Testing

NASA Technical Reports Server (NTRS)

Brooks, David E.; Gassman, Holly; Beering, Dave R.; Welch, Arun; Hoder, Douglas J.; Ivancic, William D.

1999-01-01

Transmission Control Protocol (TCP) is the underlying protocol used within the Internet for reliable information transfer. As such, there is great interest to have all implementations of TCP efficiently interoperate. This is particularly important for links exhibiting long bandwidth-delay products. The tools exist to perform TCP analysis at low rates and low delays. However, for extremely high-rate and lone-delay links such as 622 Mbps over geosynchronous satellites, new tools and testing techniques are required. This paper describes the tools and techniques used to analyze and debug various TCP implementations over high-speed, long-delay links.

5. A high speed sequential decoder

NASA Technical Reports Server (NTRS)

Lum, H., Jr.

1972-01-01

The performance and theory of operation for the High Speed Hard Decision Sequential Decoder are delineated. The decoder is a forward error correction system which is capable of accepting data from binary-phase-shift-keyed and quadriphase-shift-keyed modems at input data rates up to 30 megabits per second. Test results show that the decoder is capable of maintaining a composite error rate of 0.00001 at an input E sub b/N sub o of 5.6 db. This performance has been obtained with minimum circuit complexity.

6. Displacement speeds in turbulent premixed flame simulations

SciTech Connect

Day, Marcus S.; Shepherd, Ian G.; Bell, J.; Grcar, Joseph F.; Lijewski, Michael J.

2007-07-01

The theory of turbulent premixed flames is based on acharacterization of the flame as a discontinuous surface propagatingthrough the fluid. The displacement speed, defined as the local speed ofthe flame front normal to itself, relative to the unburned fluid,provides one characterization of the burning velocity. In this paper, weintroduce a geometric approach to computing displacement speed anddiscuss the efficacy of the displacement speed for characterizing aturbulent flame.

7. Factors Affecting the Speed of Free Writing

ERIC Educational Resources Information Center

Ferrier, Jonathan; Horne, Joanna; Singleton, Chris

2013-01-01

Factors affecting the free writing speed of 11-year-old students were investigated using the Group and Individual Assessment of Handwriting Speed. Intelligence, gender, legibility and whether the student has special educational needs or speaks English as an additional language were all found to impact on writing speed to a significant extent. In…

8. Reading Speed of Contracted French Braille

ERIC Educational Resources Information Center

Laroche, Louise; Boule, Jacinthe; Wittich, Walter

2012-01-01

This study was designed to address three hypotheses: (1) The reading speed of both readers of French braille and readers of French print will be faster in the silent condition; however, this gain in speed will be larger for print readers; (2) Individuals who acquired braille before age 10 will display faster reading speeds at lower error rates…

9. Basic principles of variable speed drives

NASA Technical Reports Server (NTRS)

Loewenthal, S. H.

1973-01-01

An understanding of the principles which govern variable speed drive operation is discussed for successful drive application. The fundamental factors of torque, speed ratio, and power as they relate to drive selection are discussed. The basic types of variable speed drives, their operating characteristics and their applications are also presented.

10. 45 CFR 3.26 - Speed limit.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 1 2013-10-01 2013-10-01 false Speed limit. 3.26 Section 3.26 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.26 Speed limit. The speed limit is 25 miles...