Sample records for safe distances calculation

  1. Efficient distance calculation using the spherically-extended polytope (s-tope) model

    NASA Technical Reports Server (NTRS)

    Hamlin, Gregory J.; Kelley, Robert B.; Tornero, Josep

    1991-01-01

    An object representation scheme which allows for Euclidean distance calculation is presented. The object model extends the polytope model by representing objects as the convex hull of a finite set of spheres. An algorithm for calculating distances between objects is developed which is linear in the total number of spheres specifying the two objects.

  2. Safe distance car-following model including backward-looking and its stability analysis

    NASA Astrophysics Data System (ADS)

    Yang, Da; Jin, Peter Jing; Pu, Yun; Ran, Bin

    2013-03-01

    The focus of this paper is the car-following behavior including backward-looking, simply called the bi-directional looking car-following behavior. This study is motivated by the potential changes of the physical properties of traffic flow caused by the fast developing intelligent transportation system (ITS), especially the new connected vehicle technology. Existing studies on this topic focused on general motors (GM) models and optimal velocity (OV) models. The safe distance car-following model, Gipps' model, which is more widely used in practice have not drawn too much attention in the bi-directional looking context. This paper explores the property of the bi-directional looking extension of Gipps' safe distance model. The stability condition of the proposed model is derived using the linear stability theory and is verified using numerical simulations. The impacts of the driver and vehicle characteristics appeared in the proposed model on the traffic flow stability are also investigated. It is found that taking into account the backward-looking effect in car-following has three types of effect on traffic flow: stabilizing, destabilizing and producing non-physical phenomenon. This conclusion is more sophisticated than the study results based on the OV bi-directional looking car-following models. Moreover, the drivers who have the smaller reaction time or the larger additional delay and think the other vehicles have larger maximum decelerations can stabilize traffic flow.

  3. The neural substrates of driving at a safe distance: a functional MRI study.

    PubMed

    Uchiyama, Yuji; Ebe, Kazutoshi; Kozato, Akio; Okada, Tomohisa; Sadato, Norihiro

    2003-12-11

    An important driving skill is the ability to maintain a safe distance from a preceding car. To determine the neural substrates of this skill we performed functional magnetic resonance imaging of simulated driving in 21 subjects. Subjects used a joystick to adjust their own driving speed in order to maintain a constant distance from a preceding car traveling at varying speeds. The task activated multiple brain regions. Activation of the cerebellum may reflect visual feedback during smooth tracking of the preceding car. Co-activation of the basal ganglia, thalamus and premotor cortex is related to movement selection. Activation of a premotor-parietal network is related to visuo-motor co-ordination. Task performance was negatively correlated with anterior cingulate activity, consistent with the role of this region in error detection and response selection.

  4. Development of the table of initial isolation distances and protective action distances for the 2004 emergency response guidebook.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, D. F.; Freeman, W. A.; Carhart, R. A.

    2005-09-23

    This report provides technical documentation for values in the Table of Initial Isolation and Protective Action Distances (PADs) in the 2004 Emergency Response Guidebook (ERG2004). The objective for choosing the PADs specified in the ERG2004 is to balance the need to adequately protect the public from exposure to potentially harmful substances against the risks and expenses that could result from overreacting to a spill. To quantify this balance, a statistical approach is adopted, whereby the best available information is used to conduct an accident scenario analysis and develop a set of up to 1,000,000 hypothetical incidents. The set accounts formore » differences in containers types, incident types, accident severity (i.e., amounts released), locations, times of day, times of year, and meteorological conditions. Each scenario is analyzed using detailed emission rate and atmospheric dispersion models to calculate the downwind chemical concentrations from which a 'safe distance' is determined. The safe distance is defined as the distance downwind from the source at which the chemical concentration falls below health protection criteria. The American Industrial Hygiene Association's Emergency Response Planning Guideline Level 2 (ERPG-2) or equivalent is the health criteria used. The statistical sample of safe distance values for all incidents considered in the analysis are separated into four categories: small spill/daytime release, small spill/nighttime release, large spill/daytime release, and large spill/nighttime release. The 90th-percentile safe distance values for each of these groups became the PADs that appear in the ERG2004.« less

  5. Copernican Mathematics: Calculating Periods and Distances of the Planets

    ERIC Educational Resources Information Center

    Rosenkrantz, Kurt J.

    2004-01-01

    The heliocentric, or Sun-centered model, one of the most important revolutions in scientific thinking, allowed Nicholas Copernicus to calculate the periods, relative distances, and approximate orbital shapes of all the known planets, thereby paving the way for Kepler's laws and Newton's formation of gravitation. Recreating Copernicus's…

  6. The safe zone for avoiding suprascapular nerve injury during shoulder arthroscopy: an anatomical study on 500 dry scapulae.

    PubMed

    Gumina, Stefano; Albino, Paolo; Giaracuni, Marco; Vestri, Annarita; Ripani, Maurizio; Postacchini, Franco

    2011-12-01

    Suprascapular nerve injury may be a complication during shoulder arthroscopy. Our aim was to verify the reliability of the existing data, assess the differences between scapulae in the 2 genders and in the same subject, obtain a safe zone useful to avoid iatrogenic nerve lesions, and analyze the existing correlations between the scapular dimensions and the safe zone. We examined 500 dried scapulae, measuring 6 distances for each one, referring to the scapular body, glenoid, and the course of the suprascapular nerve, also catalogued according to gender and side. Differences due to gender were assessed comparing mean ± sd of each distance in males and females; paired t test was used to compare distances deriving from each couple. Successively, we calculated our safe zone and Pearson's correlation. We found nonsignificant differences between the right and left distances deriving from each couple; differences due to gender were stated. We defined 3 kinds of safe zones referring to: 500 scapulae; males (139 scapulae) and females (147 scapulae). The correlation indexes calculated between the axis of the scapular body and glenoid, and the posterosuperior distance (referring to the suprascapular nerve) were 0.624, 0.694, 0.675, 0.638; while those with the posterior distance were 0.230, 0.294, 0.232, 0.284. Knowledge of the safe zone, for avoiding suprascapular nerve injury, is important; gender and specific scapular dimensions should be evaluated, as they influence the dimensions of the safe zone. The linear predictors should be used to obtain specific values of the posterosuperior limit in each patient. Copyright © 2011 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  7. A Calculation Method of Electric Distance and Subarea Division Application Based on Transmission Impedance

    NASA Astrophysics Data System (ADS)

    Fang, G. J.; Bao, H.

    2017-12-01

    The widely used method of calculating electric distances is sensitivity method. The sensitivity matrix is the result of linearization and based on the hypothesis that the active power and reactive power are decoupled, so it is inaccurate. In addition, it calculates the ratio of two partial derivatives as the relationship of two dependent variables, so there is no physical meaning. This paper presents a new method for calculating electrical distance, namely transmission impedance method. It forms power supply paths based on power flow tracing, then establishes generalized branches to calculate transmission impedances. In this paper, the target of power flow tracing is S instead of Q. Q itself has no direction and the grid delivers complex power so that S contains more electrical information than Q. By describing the power transmission relationship of the branch and drawing block diagrams in both forward and reverse directions, it can be found that the numerators of feedback parts of two block diagrams are all the transmission impedances. To ensure the distance is scalar, the absolute value of transmission impedance is defined as electrical distance. Dividing network according to the electric distances and comparing with the results of sensitivity method, it proves that the transmission impedance method can adapt to the dynamic change of system better and reach a reasonable subarea division scheme.

  8. Be-safe travel, a web-based geographic application to explore safe-route in an area

    NASA Astrophysics Data System (ADS)

    Utamima, Amalia; Djunaidy, Arif

    2017-08-01

    In large cities in developing countries, the various forms of criminality are often found. For instance, the most prominent crimes in Surabaya, Indonesia is 3C, that is theft with violence (curas), theft by weighting (curat), and motor vehicle theft (curanmor). 3C case most often occurs on the highway and residential areas. Therefore, new entrants in an area should be aware of these kind of crimes. Route Planners System or route planning system such as Google Maps only consider the shortest distance in the calculation of the optimal route. The selection of the optimal path in this study not only consider the shortest distance, but also involves other factors, namely the security level. This research considers at the need for an application to recommend the safest road to be passed by the vehicle passengers while drive an area. This research propose Be-Safe Travel, a web-based application using Google API that can be accessed by people who like to drive in an area, but still lack of knowledge of the pathways which are safe from crime. Be-Safe Travel is not only useful for the new entrants, but also useful for delivery courier of valuables goods to go through the safest streets.

  9. Recommendations for Safe Separation Distances from the Kennedy Space Center (KSC) Vehicle Assembly Building (VAB) Using a Heat-Flux-Based Analytical Approach (Abridged)

    NASA Technical Reports Server (NTRS)

    Cragg, Clinton H.; Bowman, Howard; Wilson, John E.

    2011-01-01

    The NASA Engineering and Safety Center (NESC) was requested to provide computational modeling to support the establishment of a safe separation distance surrounding the Kennedy Space Center (KSC) Vehicle Assembly Building (VAB). The two major objectives of the study were 1) establish a methodology based on thermal flux to determine safe separation distances from the Kennedy Space Center's (KSC's) Vehicle Assembly Building (VAB) with large numbers of solid propellant boosters containing hazard division 1.3 classification propellants, in case of inadvertent ignition; and 2) apply this methodology to the consideration of housing eight 5-segment solid propellant boosters in the VAB. The results of the study are contained in this report.

  10. An algorithm for calculating minimum Euclidean distance between two geographic features

    NASA Astrophysics Data System (ADS)

    Peuquet, Donna J.

    1992-09-01

    An efficient algorithm is presented for determining the shortest Euclidean distance between two features of arbitrary shape that are represented in quadtree form. These features may be disjoint point sets, lines, or polygons. It is assumed that the features do not overlap. Features also may be intertwined and polygons may be complex (i.e. have holes). Utilizing a spatial divide-and-conquer approach inherent in the quadtree data model, the basic rationale is to narrow-in on portions of each feature quickly that are on a facing edge relative to the other feature, and to minimize the number of point-to-point Euclidean distance calculations that must be performed. Besides offering an efficient, grid-based alternative solution, another unique and useful aspect of the current algorithm is that is can be used for rapidly calculating distance approximations at coarser levels of resolution. The overall process can be viewed as a top-down parallel search. Using one list of leafcode addresses for each of the two features as input, the algorithm is implemented by successively dividing these lists into four sublists for each descendant quadrant. The algorithm consists of two primary phases. The first determines facing adjacent quadrant pairs where part or all of the two features are separated between the two quadrants, respectively. The second phase then determines the closest pixel-level subquadrant pairs within each facing quadrant pair at the lowest level. The key element of the second phase is a quick estimate distance heuristic for further elimination of locations that are not as near as neighboring locations.

  11. Radiological analysis of minimal safe distance and optimal screw angle to avoid facet violation in open-door laminoplasty using precontoured plate.

    PubMed

    Min, Woo-Kie; Seo, Il; Na, Sang-Bong; Choi, Young-Seo; Choi, Ji-Yeon

    2017-01-01

    This study aimed to present radiologic analysis of minimal safe distance (MSD) and optimal screw angle (OSA) that enables to fix screws in a lateral mass safely without facet joint violation in open-door laminoplasty using a plate. A retrospective analysis was made of 22 patients (male: 17; female: 5), average age 62 years. Seventy-nine lateral mass screws were fixed among a total of 158 screws. MSD that doesn't allow 5-mm screws to violate a facet joint was measured for C3-C7 and a comparative analysis was performed. If the MSD is not secured, the OSA to be given to the cephalad direction is calculated to avoid violation of the facet joint. The screws violating inferior facet joints accounted for 34.1% of the screws fixed in inferior lateral mass. Joint surface to distal mini-screw distances were 3.18 ± 1.46 mm and 4.75 ± 1.71 mm in groups of facet joint violation and non-facet violation (FV), respectively ( p = 0.001). When 5-mm screws were inserted into a lateral mass, MSD was 4.39 ± 0.83 mm. The average MSD of C3, C4, and C5 was 4.05 ± 0.78 mm, 4.10 ± 0.70 mm, and 4.26 ± 0.74 mm, respectively. There was no significant differences among levels ( p > 0.05). The average MSD of C6 and C7 was 4.92 ± 0.81 mm and 4.80 ± 0.96 mm, respectively, showing significant differences from those of C3, C4, and C5 ( p < 0.05). If 6 mm of the MSD isn't secured, OSA showed in the cephalad direction of 11.5° for 5 mm and 22° for 4 mm approximately. We suggest that mini-screw on lateral mass can be fixed safely without FV, if they are fixed at MSD of 6 mm from a joint surface. Facet joint violation doesn't occur if an OSA is given in the cephalad direction in case of not enough MSD for mini-screws.

  12. Calculated viscosity-distance dependence for some actively flowing lavas

    NASA Technical Reports Server (NTRS)

    Pieri, David

    1987-01-01

    The importance of viscosity as a gauge of the various energy and momentum dissipation regimes of lava flows has been realized for a long time. Nevertheless, despite its central role in lava dynamics and kinematics, it remains among the most difficult of flow physical properties to measure in situ during an eruption. Attempts at reconstructing the actual emplacement viscosities of lava flows from their solidified topographic form are difficult. Where data are available on the position of an advancing flow front as a function of time, it is possible to calculate the effective viscosity of the front as a function of distance from the vent, under the assumptions of a steady state regime. As an application and test of an equation given, relevant parameters from five recent flows on Mauna Loa and Kilauea were utilized to infer the dynamic structure of their aggregate flow front viscosity as they advanced, up to cessation. The observed form of the viscosity-distance relation for the five active Hawaiian flows examined appears to be exponential, with a rapid increase just before the flows stopped as one would expect.

  13. On the calculation of low-thrust fail-safe trajectories

    NASA Technical Reports Server (NTRS)

    Sauer, C. G., Jr.

    1975-01-01

    A guidance algorithm is developed for a low-thrust spacecraft such that target intercept is possible in spite of premature thrust termination along the trajectory. Such a trajectory is called a 'fail-safe' trajectory and the spacecraft thrust is utilized to minimize the relative target-spacecraft approach speed. The fail-safe guidance algorithm is solved using the concept of a critical thrust plane and a non-critical thrust direction. Several examples of fail-safe guidance are presented for a solar-electric propulsion flyby mission to the comet Encke.

  14. Calculating Reuse Distance from Source Code

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Narayanan, Sri Hari Krishna; Hovland, Paul

    The efficient use of a system is of paramount importance in high-performance computing. Applications need to be engineered for future systems even before the architecture of such a system is clearly known. Static performance analysis that generates performance bounds is one way to approach the task of understanding application behavior. Performance bounds provide an upper limit on the performance of an application on a given architecture. Predicting cache hierarchy behavior and accesses to main memory is a requirement for accurate performance bounds. This work presents our static reuse distance algorithm to generate reuse distance histograms. We then use these histogramsmore » to predict cache miss rates. Experimental results for kernels studied show that the approach is accurate.« less

  15. Elongated Asteroid Will Safely Pass Earth on Christmas Eve

    NASA Image and Video Library

    2015-12-23

    The elongated asteroid in this radar image, named 2003 SD220, will safely fly past Earth on Thursday, Dec. 24, 2015, at a distance of 6.8 million miles (11 million kilometers). The image was taken on Dec. 22 by scientists using NASA's 230-foot (70-meter) Deep Space Network antenna at Goldstone, California, when the asteroid was approaching its flyby distance. This asteroid is at least 3,600 feet (1,100 meters) long. In 2018, it will safely pass Earth at a distance of 1.8 million miles (2.8 million kilometers). http://photojournal.jpl.nasa.gov/catalog/PIA20280

  16. Recording and Calculating Gunshot Sound—Change of the Volume in Reference to the Distance

    NASA Astrophysics Data System (ADS)

    Nikolaos, Tsiatis E.

    2010-01-01

    An experiment was conducted in an open practice ground (shooting range) regarding the recording of the sound of gunshots. Shots were fired using various types of firearms (seven pistols, five revolvers, two submachine guns, one rifle, and one shotgun) in different calibers, from several various distances with reference to the recording sources. Both, a conventional sound level meter (device) and a measurement microphone were used, having been placed in a fixed point behind the shooting line. The sound of each shot was recorded (from the device). At the same time the signal received by the microphone was transferred to a connected computer through an appropriate audio interface with a pre-amplifier. Each sound wave was stored and depicted as a wave function. After the physic-mathematical analysis of these depictions, the volume was calculated in the accepted engineering units(Decibels or dB) of Sound Pressure Level (SPL). The distances from the recording sources were 9.60 meters, 14.40 m, 19.20 m, and 38.40 m. The experiment was carried out by using the following calibers: .22 LR, 6.35 mm(.25 AUTO), 7.62 mm Tokarev(7,62×25), 7.65 mm(.32 AUTO), 9 mm Parabellum(9×19), 9 mm Short(9×17), 9 mm Makarov(9×18), .45 AUTO, .32 S&W, .38 S&W, .38 SPECIAL, .357 Magnum, 7,62 mm Kalashnikov(7,62×39) and 12 GA. Tables are given for the environmental conditions (temperature, humidity, altitude & barometric pressure), the length of the barrel of each gun, technical characteristics of the used ammunition, as well as for the volume taken from the SLM. The data for the sound intensity were collected after 168 gunshots (158 single shot & 10 bursts). According to the results, a decreasing of the volume, equivalent to the increasing of the distance, was remarked, as it was expected. Values seem to follow the Inverse square Law. For every doubling of the distance from the sound source, the sound intensity diminishes by 5.9904±0.2325 decibels (on average). In addition, we have the

  17. [A New Distance Metric between Different Stellar Spectra: the Residual Distribution Distance].

    PubMed

    Liu, Jie; Pan, Jing-chang; Luo, A-li; Wei, Peng; Liu, Meng

    2015-12-01

    Distance metric is an important issue for the spectroscopic survey data processing, which defines a calculation method of the distance between two different spectra. Based on this, the classification, clustering, parameter measurement and outlier data mining of spectral data can be carried out. Therefore, the distance measurement method has some effect on the performance of the classification, clustering, parameter measurement and outlier data mining. With the development of large-scale stellar spectral sky surveys, how to define more efficient distance metric on stellar spectra has become a very important issue in the spectral data processing. Based on this problem and fully considering of the characteristics and data features of the stellar spectra, a new distance measurement method of stellar spectra named Residual Distribution Distance is proposed. While using this method to measure the distance, the two spectra are firstly scaled and then the standard deviation of the residual is used the distance. Different from the traditional distance metric calculation methods of stellar spectra, when used to calculate the distance between stellar spectra, this method normalize the two spectra to the same scale, and then calculate the residual corresponding to the same wavelength, and the standard error of the residual spectrum is used as the distance measure. The distance measurement method can be used for stellar classification, clustering and stellar atmospheric physical parameters measurement and so on. This paper takes stellar subcategory classification as an example to test the distance measure method. The results show that the distance defined by the proposed method is more effective to describe the gap between different types of spectra in the classification than other methods, which can be well applied in other related applications. At the same time, this paper also studies the effect of the signal to noise ratio (SNR) on the performance of the proposed method

  18. Calculating Galactic Distances Through Supernova Light Curve Analysis (Abstract)

    NASA Astrophysics Data System (ADS)

    Glanzer, J.

    2018-06-01

    (Abstract only) The purpose of this project is to experimentally determine the distance to the galaxy M101 by using data that were taken on the type Ia supernova SN 2011fe at the Paul P. Feder Observatory. Type Ia supernovae are useful for determining distances in astronomy because they all have roughly the same luminosity at the peak of their outburst. Comparing the apparent magnitude to the absolute magnitude allows a measurement of the distance. The absolute magnitude is estimated in two ways: using an empirical relationship from the literature between the rate of decline and the absolute magnitude, and using sncosmo, a PYTHON package used for supernova light curve analysis that fits model light curves to the photometric data.

  19. A generalized equation for the calculation of receptor noise limited colour distances in n-chromatic visual systems

    PubMed Central

    Clark, R. C.; Brebner, J. S.

    2017-01-01

    Researchers must assess similarities and differences in colour from an animal's eye view when investigating hypotheses in ecology, evolution and behaviour. Nervous systems generate colour perceptions by comparing the responses of different spectral classes of photoreceptor through colour opponent mechanisms, and the performance of these mechanisms is limited by photoreceptor noise. Accordingly, the receptor noise limited (RNL) colour distance model of Vorobyev and Osorio (Vorobyev & Osorio 1998 Proc. R. Soc. Lond. B 265, 351–358 (doi:10.1098/rspb.1998.0302)) generates predictions about the discriminability of colours that agree with behavioural data, and consequently it has found wide application in studies of animal colour vision. Vorobyev and Osorio (1998) provide equations to calculate RNL colour distances for animals with di-, tri- and tetrachromatic vision, which is adequate for many species. However, researchers may sometimes wish to compute RNL colour distances for potentially more complex colour visual systems. Thus, we derive a simple, single formula for the computation of RNL distance between two measurements of colour, equivalent to the published di-, tri- and tetrachromatic equations of Vorobyev and Osorio (1998), and valid for colour visual systems with any number of types of noisy photoreceptors. This formula will allow the easy application of this important colour visual model across the fields of ecology, evolution and behaviour. PMID:28989773

  20. The application of multilayer elastic beam in MEMS safe and arming system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Guozhong, E-mail: liguozhong-bit@bit.edu.cn; Shi, Gengchen; Sui, Li

    In this paper, a new approach for a multilayer elastic beam to provide a driving force and driving distance for a MEMS safe and arming system is presented. In particular this is applied where a monolayer elastic beam cannot provide adequate driving force and driving distance at the same time in limited space. Compared with thicker elastic beams, the bilayer elastic beam can provide twice the driving force of a monolayer beam to guarantee the MEMS safe and arming systems work reliably without decreasing the driving distance. In this paper, the theoretical analysis, numerical simulation and experimental verification of themore » multilayer elastic beam is presented. The numerical simulation and experimental results show that the bilayer elastic provides 1.8–2 times the driving force of a monolayer, and a method that improves driving force without reducing the driving distance.« less

  1. New method for distance-based close following safety indicator.

    PubMed

    Sharizli, A A; Rahizar, R; Karim, M R; Saifizul, A A

    2015-01-01

    The increase in the number of fatalities caused by road accidents involving heavy vehicles every year has raised the level of concern and awareness on road safety in developing countries like Malaysia. Changes in the vehicle dynamic characteristics such as gross vehicle weight, travel speed, and vehicle classification will affect a heavy vehicle's braking performance and its ability to stop safely in emergency situations. As such, the aim of this study is to establish a more realistic new distance-based safety indicator called the minimum safe distance gap (MSDG), which incorporates vehicle classification (VC), speed, and gross vehicle weight (GVW). Commercial multibody dynamics simulation software was used to generate braking distance data for various heavy vehicle classes under various loads and speeds. By applying nonlinear regression analysis to the simulation results, a mathematical expression of MSDG has been established. The results show that MSDG is dynamically changed according to GVW, VC, and speed. It is envisaged that this new distance-based safety indicator would provide a more realistic depiction of the real traffic situation for safety analysis.

  2. Approaching Suspicious Substances Safely

    NASA Technical Reports Server (NTRS)

    2004-01-01

    A mineral identification tool that was developed for NASA's Mars Rover Technology Development program is now serving as a powerful tool for U.S. law enforcement agencies and military personnel to identify suspicious liquid and solid substances. The tool can measure unknown substances through glass and plastic packaging materials with the RamanProbe(TradeMark) focused fiber-optic probe. The probe length can be extended up to 200 meters to enable users to analyze potentially dangerous substances at a safe distance. In many cases, the spectrometer and personnel are kept in a safe zone while the probe is positioned next to the sample being analyzed. Being able to identify chemicals in remote locations also saves users time and labor, since otherwise the samples would need to be collected, transported, and prepared prior to measurement in the laboratory.

  3. Standard operating procedure for calculating genome-to-genome distances based on high-scoring segment pairs.

    PubMed

    Auch, Alexander F; Klenk, Hans-Peter; Göker, Markus

    2010-01-28

    DNA-DNA hybridization (DDH) is a widely applied wet-lab technique to obtain an estimate of the overall similarity between the genomes of two organisms. To base the species concept for prokaryotes ultimately on DDH was chosen by microbiologists as a pragmatic approach for deciding about the recognition of novel species, but also allowed a relatively high degree of standardization compared to other areas of taxonomy. However, DDH is tedious and error-prone and first and foremost cannot be used to incrementally establish a comparative database. Recent studies have shown that in-silico methods for the comparison of genome sequences can be used to replace DDH. Considering the ongoing rapid technological progress of sequencing methods, genome-based prokaryote taxonomy is coming into reach. However, calculating distances between genomes is dependent on multiple choices for software and program settings. We here provide an overview over the modifications that can be applied to distance methods based in high-scoring segment pairs (HSPs) or maximally unique matches (MUMs) and that need to be documented. General recommendations on determining HSPs using BLAST or other algorithms are also provided. As a reference implementation, we introduce the GGDC web server (http://ggdc.gbdp.org).

  4. Distance Running and the Elementary-Age Child

    ERIC Educational Resources Information Center

    Jenny, Seth; Armstrong, Tess

    2013-01-01

    Distance running is often underutilized in elementary physical education due to three common misconceptions about using this activity with young children: (1) it is not enjoyable, (2) it is not safe, and (3) children will get mentally "burned out." Through reviewing the literature and offering guidelines, practical tips, instant…

  5. Simulation of Reversible Protein–Protein Binding and Calculation of Binding Free Energies Using Perturbed Distance Restraints

    PubMed Central

    2017-01-01

    Virtually all biological processes depend on the interaction between proteins at some point. The correct prediction of biomolecular binding free-energies has many interesting applications in both basic and applied pharmaceutical research. While recent advances in the field of molecular dynamics (MD) simulations have proven the feasibility of the calculation of protein–protein binding free energies, the large conformational freedom of proteins and complex free energy landscapes of binding processes make such calculations a difficult task. Moreover, convergence and reversibility of resulting free-energy values remain poorly described. In this work, an easy-to-use, yet robust approach for the calculation of standard-state protein–protein binding free energies using perturbed distance restraints is described. In the binding process the conformations of the proteins were restrained, as suggested earlier. Two approaches to avoid end-state problems upon release of the conformational restraints were compared. The method was evaluated by practical application to a small model complex of ubiquitin and the very flexible ubiquitin-binding domain of human DNA polymerase ι (UBM2). All computed free energy differences were closely monitored for convergence, and the calculated binding free energies had a mean unsigned deviation of only 1.4 or 2.5 kJ·mol–1 from experimental values. Statistical error estimates were in the order of thermal noise. We conclude that the presented method has promising potential for broad applicability to quantitatively describe protein–protein and various other kinds of complex formation. PMID:28898077

  6. Automobile Stopping Distances.

    ERIC Educational Resources Information Center

    Logue, L. J.

    1979-01-01

    Discusses the effect of vehicle mass on stopping distances. Analyzes an example of a sample vehicle and tire, and calculates the braking acceleration showing the effect of different factors on the stopping performance of the tires. (GA)

  7. Gauge-invariance and infrared divergences in the luminosity distance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biern, Sang Gyu; Yoo, Jaiyul, E-mail: sgbiern@physik.uzh.ch, E-mail: jyoo@physik.uzh.ch

    2017-04-01

    Measurements of the luminosity distance have played a key role in discovering the late-time cosmic acceleration. However, when accounting for inhomogeneities in the Universe, its interpretation has been plagued with infrared divergences in its theoretical predictions, which are in some cases used to explain the cosmic acceleration without dark energy. The infrared divergences in most calculations are artificially removed by imposing an infrared cut-off scale. We show that a gauge-invariant calculation of the luminosity distance is devoid of such divergences and consistent with the equivalence principle, eliminating the need to impose a cut-off scale. We present proper numerical calculations ofmore » the luminosity distance using the gauge-invariant expression and demonstrate that the numerical results with an ad hoc cut-off scale in previous calculations have negligible systematic errors as long as the cut-off scale is larger than the horizon scale. We discuss the origin of infrared divergences and their cancellation in the luminosity distance.« less

  8. Optical Distance Measurement Device And Method Thereof

    DOEpatents

    Bowers, Mark W.

    2004-06-15

    A system and method of efficiently obtaining distance measurements of a target by scanning the target. An optical beam is provided by a light source and modulated by a frequency source. The modulated optical beam is transmitted to an acousto-optical deflector capable of changing the angle of the optical beam in a predetermined manner to produce an output for scanning the target. In operation, reflected or diffused light from the target may be received by a detector and transmitted to a controller configured to calculate the distance to the target as well as the measurement uncertainty in calculating the distance to the target.

  9. The Safe Yield and Climatic Variability: Implications for Groundwater Management.

    PubMed

    Loáiciga, Hugo A

    2017-05-01

    Methods for calculating the safe yield are evaluated in this paper using a high-quality and long historical data set of groundwater recharge, discharge, extraction, and precipitation in a karst aquifer. Consideration is given to the role that climatic variability has on the determination of a climatically representative period with which to evaluate the safe yield. The methods employed to estimate the safe yield are consistent with its definition as a long-term average extraction rate that avoids adverse impacts on groundwater. The safe yield is a useful baseline for groundwater planning; yet, it is herein shown that it is not an operational rule that works well under all climatic conditions. This paper shows that due to the nature of dynamic groundwater processes it may be most appropriate to use an adaptive groundwater management strategy that links groundwater extraction rates to groundwater discharge rates, thus achieving a safe yield that represents an estimated long-term sustainable yield. An example of the calculation of the safe yield of the Edwards Aquifer (Texas) demonstrates that it is about one-half of the average annual recharge. © 2016, National Ground Water Association.

  10. Setback distances between small biological wastewater treatment systems and drinking water wells against virus contamination in alluvial aquifers.

    PubMed

    Blaschke, A P; Derx, J; Zessner, M; Kirnbauer, R; Kavka, G; Strelec, H; Farnleitner, A H; Pang, L

    2016-12-15

    Contamination of groundwater by pathogenic viruses from small biological wastewater treatment system discharges in remote areas is a major concern. To protect drinking water wells against virus contamination, safe setback distances are required between wastewater disposal fields and water supply wells. In this study, setback distances are calculated for alluvial sand and gravel aquifers for different vadose zone and aquifer thicknesses and horizontal groundwater gradients. This study applies to individual households and small settlements (1-20 persons) in decentralized locations without access to receiving surface waters but with the legal obligation of biological wastewater treatment. The calculations are based on Monte Carlo simulations using an analytical model that couples vertical unsaturated and horizontal saturated flow with virus transport. Hydraulic conductivities and water retention curves were selected from reported distribution functions depending on the type of subsurface media. The enteric virus concentration in effluent discharge was calculated based on reported ranges of enteric virus concentration in faeces, virus infectivity, suspension factor, and virus reduction by mechanical-biological wastewater treatment. To meet the risk target of <10 -4 infections/person/year, a 12 log 10 reduction was required, using a linear dose-response relationship for the total amount of enteric viruses, at very low exposure concentrations. The results of this study suggest that the horizontal setback distances vary widely ranging 39 to 144m in sand aquifers, 66-289m in gravel aquifers and 1-2.5km in coarse gravel aquifers. It also varies for the same aquifers, depending on the thickness of the vadose zones and the groundwater gradient. For vulnerable fast-flow alluvial aquifers like coarse gravels, the calculated setback distances were too large to achieve practically. Therefore, for this category of aquifer, a high level of treatment is recommended before the

  11. Non-LTE model calculations for SN 1987A and the extragalactic distance scale

    NASA Technical Reports Server (NTRS)

    Schmutz, W.; Abbott, D. C.; Russell, R. S.; Hamann, W.-R.; Wessolowski, U.

    1990-01-01

    This paper presents model atmospheres for the first week of SN 1987A, based on the luminosity and density/velocity structure from hydrodynamic models of Woosley (1988). The models account for line blanketing, expansion, sphericity, and departures from LTE in hydrogen and helium and differ from previously published efforts because they represent ab initio calculations, i.e., they contain essentially no free parameters. The formation of the UV spectrum is dominated by the effects of line blanketing. In the absorption troughs, the Balmer line profiles were fit well by these models, but the observed emissions are significantly stronger than predicted, perhaps due to clumping. The generally good agreement between the present synthetic spectra and observations provides independent support for the overall accuracy of the hydrodynamic models of Woosley. The question of the accuracy of the Baade-Wesselink method is addressed in a detailed discussion of its approximations. While the application of the standard method produces a distance within an uncertainty of 20 percent in the case of SN 1987A, systematic errors up to a factor of 2 are possible, particularly if the precursor was a red supergiant.

  12. The determination of pair-distance distribution by double electron-electron resonance: regularization by the length of distance discretization with Monte Carlo calculations

    NASA Astrophysics Data System (ADS)

    Dzuba, Sergei A.

    2016-08-01

    Pulsed double electron-electron resonance technique (DEER, or PELDOR) is applied to study conformations and aggregation of peptides, proteins, nucleic acids, and other macromolecules. For a pair of spin labels, experimental data allows for the determination of their distance distribution function, P(r). P(r) is derived as a solution of a first-kind Fredholm integral equation, which is an ill-posed problem. Here, we suggest regularization by increasing the distance discretization length to its upper limit where numerical integration still provides agreement with experiment. This upper limit is found to be well above the lower limit for which the solution instability appears because of the ill-posed nature of the problem. For solving the integral equation, Monte Carlo trials of P(r) functions are employed; this method has an obvious advantage of the fulfillment of the non-negativity constraint for P(r). The regularization by the increasing of distance discretization length for the case of overlapping broad and narrow distributions may be employed selectively, with this length being different for different distance ranges. The approach is checked for model distance distributions and for experimental data taken from literature for doubly spin-labeled DNA and peptide antibiotics.

  13. The ideal subject distance for passport pictures.

    PubMed

    Verhoff, Marcel A; Witzel, Carsten; Kreutz, Kerstin; Ramsthaler, Frank

    2008-07-04

    In an age of global combat against terrorism, the recognition and identification of people on document images is of increasing significance. Experiments and calculations have shown that the camera-to-subject distance - not the focal length of the lens - can have a significant effect on facial proportions. Modern passport pictures should be able to function as a reference image for automatic and manual picture comparisons. This requires a defined subject distance. It is completely unclear which subject distance, in the taking of passport photographs, is ideal for the recognition of the actual person. We show here that the camera-to-subject distance that is perceived as ideal is dependent on the face being photographed, even if the distance of 2m was most frequently preferred. So far the problem of the ideal camera-to-subject distance for faces has only been approached through technical calculations. We have, for the first time, answered this question experimentally with a double-blind experiment. Even if there is apparently no ideal camera-to-subject distance valid for every face, 2m can be proposed as ideal for the taking of passport pictures. The first step would actually be the determination of a camera-to-subject distance for the taking of passport pictures within the standards. From an anthropological point of view it would be interesting to find out which facial features allow the preference of a shorter camera-to-subject distance and which allow the preference of a longer camera-to-subject distance.

  14. Phase-space overlap measures. I. Fail-safe bias detection in free energies calculated by molecular simulation

    NASA Astrophysics Data System (ADS)

    Wu, Di; Kofke, David A.

    2005-08-01

    We consider ways to quantify the overlap of the parts of phase space important to two systems, labeled A and B. Of interest is how much of the A-important phase space lies in that important to B, and how much of B lies in A. Two measures are proposed. The first considers four total-energy distributions, formed from all combinations made by tabulating either the A-system or the B-system energy when sampling either the A or B system. Measures for A in B and B in A are given by two overlap integrals defined on pairs of these distributions. The second measure is based on information theory, and defines two relative entropies which are conveniently expressed in terms of the dissipated work for free-energy perturbation (FEP) calculations in the A →B and B →A directions, respectively. Phase-space overlap is an important consideration in the performance of free-energy calculations. To demonstrate this connection, we examine bias in FEP calculations applied to a system of independent particles in a harmonic potential. Systems are selected to represent a range of overlap situations, including extreme subset, subset, partial overlap, and nonoverlap. The magnitude and symmetry of the bias (A →B vs B →A) are shown to correlate well with the overlap, and consequently with the overlap measures. The relative entropies are used to scale the amount of sampling to obtain a universal bias curve. This result leads to develop a simple heuristic that can be applied to determine whether a work-based free-energy measurement is free of bias. The heuristic is based in part on the measured free energy, but we argue that it is fail-safe inasmuch as any bias in the measurement will not promote a false indication of accuracy.

  15. Measuring the Accuracy of Simple Evolving Connectionist System with Varying Distance Formulas

    NASA Astrophysics Data System (ADS)

    Al-Khowarizmi; Sitompul, O. S.; Suherman; Nababan, E. B.

    2017-12-01

    Simple Evolving Connectionist System (SECoS) is a minimal implementation of Evolving Connectionist Systems (ECoS) in artificial neural networks. The three-layer network architecture of the SECoS could be built based on the given input. In this study, the activation value for the SECoS learning process, which is commonly calculated using normalized Hamming distance, is also calculated using normalized Manhattan distance and normalized Euclidean distance in order to compare the smallest error value and best learning rate obtained. The accuracy of measurement resulted by the three distance formulas are calculated using mean absolute percentage error. In the training phase with several parameters, such as sensitivity threshold, error threshold, first learning rate, and second learning rate, it was found that normalized Euclidean distance is more accurate than both normalized Hamming distance and normalized Manhattan distance. In the case of beta fibrinogen gene -455 G/A polymorphism patients used as training data, the highest mean absolute percentage error value is obtained with normalized Manhattan distance compared to normalized Euclidean distance and normalized Hamming distance. However, the differences are very small that it can be concluded that the three distance formulas used in SECoS do not have a significant effect on the accuracy of the training results.

  16. SAFE Testing Nuclear Rockets Economically

    NASA Astrophysics Data System (ADS)

    Howe, Steven D.; Travis, Bryan; Zerkle, David K.

    2003-01-01

    Several studies over the past few decades have recognized the need for advanced propulsion to explore the solar system. As early as the 1960s, Werner Von Braun and others recognized the need for a nuclear rocket for sending humans to Mars. The great distances, the intense radiation levels, and the physiological response to zero-gravity all supported the concept of using a nuclear rocket to decrease mission time. These same needs have been recognized in later studies, especially in the Space Exploration Initiative in 1989. One of the key questions that has arisen in later studies, however, is the ability to test a nuclear rocket engine in the current societal environment. Unlike the Rover/NERVA programs in the 1960s, the rocket exhaust can no longer be vented to the open atmosphere. As a consequence, previous studies have examined the feasibility of building a large-scale version of the Nuclear Furnace Scrubber that was demonstrated in 1971. We have investigated an alternative that would deposit the rocket exhaust along with any entrained fission products directly into the ground. The Subsurface Active Filtering of Exhaust, or SAFE, concept would allow variable sized engines to be tested for long times at a modest expense. A system overview, results of preliminary calculations, and cost estimates of proof of concept demonstrations are presented. The results indicate that a nuclear rocket could be tested at the Nevada Test Site for under $20 M.

  17. A Wall-Distance-Free k-ω SST Turbulence Model

    NASA Astrophysics Data System (ADS)

    Gleize, Vincent; Burnley, Victor

    2001-11-01

    In the calculation of flows around aircraft and aerodynamic bodies, the Shear-Stress Transport (SST) model by Menter has been used extensively due to its good prediction of flows with adverse pressure gradients. One main drawback of this model is the need to calculate the distance from the wall. While this is not a serious drawback for steady state calculations on non-moving grids, this calculation can become very cumbersome and expensive for unsteady simulations, especially when using unstructured grids. In this case, the wall-distance needs to be determined after each iteration. To avoid this problem, a new model is proposed which provides the benefits of the SST correction and avoids the freestream dependency of the solution, while not requiring the wall-distance. The first results for a wide range of test cases show that this model produces very good agreement with experimental data for flows with adverse pressure gradients, separation zones and shock-boundary layer interactions, closely matching the results obtained with the original SST model. This model should be very useful for unsteady calculations, such as store separation, grid adaptation, and other practical flows.

  18. Safe sex

    MedlinePlus

    ... sex; Sexually transmitted - safe sex; GC - safe sex; Gonorrhea - safe sex; Herpes - safe sex; HIV - safe sex; ... contact. STIs include: Chlamydia Genital herpes Genital warts Gonorrhea Hepatitis HIV HPV Syphilis STIs are also called ...

  19. Safe Laser Beam Propagation for Interplanetary Links

    NASA Technical Reports Server (NTRS)

    Wilson, Keith E.

    2011-01-01

    Ground-to-space laser uplinks to Earth–orbiting satellites and deep space probes serve both as a beacon and an uplink command channel for deep space probes and Earth-orbiting satellites. An acquisition and tracking point design to support a high bandwidth downlink from a 20-cm optical terminal on an orbiting Mars spacecraft typically calls for 2.5 kW of 1030-nm uplink optical power in 40 micro-radians divergent beams.2 The NOHD (nominal ocular hazard distance) of the 1030nm uplink is in excess of 2E5 km, approximately half the distance to the moon. Recognizing the possible threat of high power laser uplinks to the flying public and to sensitive Earth-orbiting satellites, JPL developed a three-tiered system at its Optical Communications Telescope Laboratory (OCTL) to ensure safe laser beam propagation through navigational and near-Earth space.

  20. Ground-based remote sensing of volcanic CO2 and correlated SO2, HF, HCl, and BrO, in safe-distance from the crater

    NASA Astrophysics Data System (ADS)

    Butz, Andre; Solvejg Dinger, Anna; Bobrowski, Nicole; Kostinek, Julian; Fieber, Lukas; Fischerkeller, Constanze; Giuffrida, Giovanni Bruno; Hase, Frank; Klappenbach, Friedrich; Kuhn, Jonas; Lübcke, Peter; Tirpitz, Lukas; Tu, Qiansi

    2017-04-01

    Remote sensing of CO2 enhancements in volcanic plumes can be a tool to estimate volcanic CO2 emissions and thereby, to gain insight into the geological carbon cycle and into volcano interior processes. However, remote sensing of the volcanic CO2 is challenged by the large atmospheric background concentrations masking the minute volcanic signal. Here, we report on a demonstrator study conducted in September 2015 at Mt. Etna on Sicily, where we deployed an EM27/SUN Fourier Transform Spectrometer together with a UV spectrometer on a mobile remote sensing platform. The spectrometers were operated in direct-sun viewing geometry collecting cross-sectional scans of solar absorption spectra through the volcanic plume by operating the platform in stop-and-go patterns in 5 to 10 kilometers distance from the crater region. We successfully detected correlated intra-plume enhancements of CO2 and volcanic SO2, HF, HCl, and BrO. The path-integrated volcanic CO2 enhancements amounted to about 0.5 ppm (on top of the ˜400 ppm background). Key to successful detection of volcanic CO2 was A) the simultaneous observation of the O2 total column which allowed for correcting changes in the CO2 column caused by changes in observer altitude and B) the simultaneous measurement of volcanic species co-emitted with CO2 which allowed for discriminating intra-plume and extra-plume observations. The latter were used for subtracting the atmospheric CO2 background. The field study suggests that our remote sensing observatory is a candidate technique for volcano monitoring in safe distance from the crater region.

  1. Optimization of the Multi-Spectral Euclidean Distance Calculation for FPGA-based Spaceborne Systems

    NASA Technical Reports Server (NTRS)

    Cristo, Alejandro; Fisher, Kevin; Perez, Rosa M.; Martinez, Pablo; Gualtieri, Anthony J.

    2012-01-01

    Due to the high quantity of operations that spaceborne processing systems must carry out in space, new methodologies and techniques are being presented as good alternatives in order to free the main processor from work and improve the overall performance. These include the development of ancillary dedicated hardware circuits that carry out the more redundant and computationally expensive operations in a faster way, leaving the main processor free to carry out other tasks while waiting for the result. One of these devices is SpaceCube, a FPGA-based system designed by NASA. The opportunity to use FPGA reconfigurable architectures in space allows not only the optimization of the mission operations with hardware-level solutions, but also the ability to create new and improved versions of the circuits, including error corrections, once the satellite is already in orbit. In this work, we propose the optimization of a common operation in remote sensing: the Multi-Spectral Euclidean Distance calculation. For that, two different hardware architectures have been designed and implemented in a Xilinx Virtex-5 FPGA, the same model of FPGAs used by SpaceCube. Previous results have shown that the communications between the embedded processor and the circuit create a bottleneck that affects the overall performance in a negative way. In order to avoid this, advanced methods including memory sharing, Native Port Interface (NPI) connections and Data Burst Transfers have been used.

  2. The Changeable Block Distance System Analysis

    NASA Astrophysics Data System (ADS)

    Lewiński, Andrzej; Toruń, Andrzej

    The paper treats about efficiency analysis in Changeable Block Distance (CBD) System connected with wireless positioning and control of train. The analysis is based on modeling of typical ERTMS line and comparison with actual and future traffic. The calculations are related to assumed parameters of railway traffic corresponding to real time - table of distance Psary - Góra Włodowska from CMK line equipped in classic, ETCS Level 1 and ETCS with CBD systems.

  3. Prediction of distance in hammer throwing.

    PubMed

    Dapena, Jesús; Gutiérrez-Dávila, Marcos; Soto, Víctor M; Rojas, Francisco J

    2003-01-01

    The aim of this study was to determine how much the predicted distance of a hammer throw is affected by (1) ignoring air resistance and (2) assuming that the centre of mass of the hammer coincides with the centre of the ball. Three-dimensional data from actual throws (men: 72.82 +/- 7.43 m; women: 67.78 +/- 4.02 m) were used to calculate the kinematic conditions of the hammer at release. A mathematical model of the hammer was then used to simulate the three-dimensional airborne motion of the hammer and to predict the distance of the throw. The distance predicted for vacuum conditions and using the ball centre to represent the hammer centre of mass was 4.30 +/- 2.64 m longer than the official distance of the throw for the men and 8.82 +/- 3.20 m longer for the women. Predictions using the true centre of mass of the hammer reduced the discrepancy to 2.39 +/- 2.58 m for the men and 5.28 +/- 2.88 m for the women. Predictions using air resistance and the true centre of mass of the hammer further reduced the discrepancy to -0.46 +/- 2.63 m for the men and 1.16 +/- 2.31 m for the women. Approximately half the loss of distance produced by air resistance was due to forces made on the ball and the remainder to forces made on the cable and handle. Equations were derived for calculation of the effects of air resistance and of the assumption that the centre of mass of the hammer coincides with the centre of the ball, on the distance of the throw.

  4. Design and Performance Analysis of an Intrinsically Safe Ultrasonic Ranging Sensor

    PubMed Central

    Zhang, Hongjuan; Wang, Yu; Zhang, Xu; Wang, Dong; Jin, Baoquan

    2016-01-01

    In flammable or explosive environments, an ultrasonic sensor for distance measurement poses an important engineering safety challenge, because the driving circuit uses an intermediate frequency transformer as an impedance transformation element, in which the produced heat or spark is available for ignition. In this paper, an intrinsically safe ultrasonic ranging sensor is designed and implemented. The waterproof piezoelectric transducer with integrated transceiver is chosen as an energy transducing element. Then a novel transducer driving circuit is designed based on an impedance matching method considering safety spark parameters to replace an intermediate frequency transformer. Then, an energy limiting circuit is developed to achieve dual levels of over-voltage and over-current protection. The detail calculation and evaluation are executed and the electrical characteristics are analyzed to verify the intrinsic safety of the driving circuit. Finally, an experimental platform of the ultrasonic ranging sensor system is constructed, which involves short-circuit protection. Experimental results show that the proposed ultrasonic ranging sensor is excellent in both ranging performance and intrinsic safety. PMID:27304958

  5. Design and Performance Analysis of an Intrinsically Safe Ultrasonic Ranging Sensor.

    PubMed

    Zhang, Hongjuan; Wang, Yu; Zhang, Xu; Wang, Dong; Jin, Baoquan

    2016-06-13

    In flammable or explosive environments, an ultrasonic sensor for distance measurement poses an important engineering safety challenge, because the driving circuit uses an intermediate frequency transformer as an impedance transformation element, in which the produced heat or spark is available for ignition. In this paper, an intrinsically safe ultrasonic ranging sensor is designed and implemented. The waterproof piezoelectric transducer with integrated transceiver is chosen as an energy transducing element. Then a novel transducer driving circuit is designed based on an impedance matching method considering safety spark parameters to replace an intermediate frequency transformer. Then, an energy limiting circuit is developed to achieve dual levels of over-voltage and over-current protection. The detail calculation and evaluation are executed and the electrical characteristics are analyzed to verify the intrinsic safety of the driving circuit. Finally, an experimental platform of the ultrasonic ranging sensor system is constructed, which involves short-circuit protection. Experimental results show that the proposed ultrasonic ranging sensor is excellent in both ranging performance and intrinsic safety.

  6. Calculations of safe collimator settings and β* at the CERN Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Bruce, R.; Assmann, R. W.; Redaelli, S.

    2015-06-01

    The first run of the Large Hadron Collider (LHC) at CERN was very successful and resulted in important physics discoveries. One way of increasing the luminosity in a collider, which gave a very significant contribution to the LHC performance in the first run and can be used even if the beam intensity cannot be increased, is to decrease the transverse beam size at the interaction points by reducing the optical function β*. However, when doing so, the beam becomes larger in the final focusing system, which could expose its aperture to beam losses. For the LHC, which is designed to store beams with a total energy of 362 MJ, this is critical, since the loss of even a small fraction of the beam could cause a magnet quench or even damage. Therefore, the machine aperture has to be protected by the collimation system. The settings of the collimators constrain the maximum beam size that can be tolerated and therefore impose a lower limit on β*. In this paper, we present calculations to determine safe collimator settings and the resulting limit on β*, based on available aperture and operational stability of the machine. Our model was used to determine the LHC configurations in 2011 and 2012 and it was found that β* could be decreased significantly compared to the conservative model used in 2010. The gain in luminosity resulting from the decreased margins between collimators was more than a factor 2, and a further contribution from the use of realistic aperture estimates based on measurements was almost as large. This has played an essential role in the rapid and successful accumulation of experimental data in the LHC.

  7. Safe Zone of Posterior Screw Insertion for Talar Neck Fractures on 3-Dimensional Reconstruction Model.

    PubMed

    Wu, Jian-Qun; Ma, Sheng-Hui; Liu, Song; Qin, Cheng-He; Jin, Dan; Yu, Bin

    2017-02-01

    To investigate the optimal posterior screw placement and the geometry of safe zones for screw insertion in the talar neck. Computed tomography data for 15 normal feet were imported into Mimics 10.01 software for 3-dimensional reconstruction; 4.0-mm-diameter screws were simulated from the lateral tubercle of the posterior process of the talus to the talar head. The range of screw paths trajectories and screw lengths at nine locations that did not breach the cortex of the talus were evaluated. In addition, the farthest (point a) and nearest point (point b) of the safe zone to the subtalar joint at each location, the anteversion angle (angle A), which is parallel to the sagittal plane, and the horizontal angle (angle B), which is perpendicular to the sagittal plane, were measured. The safe zone was mainly between the 30% location and the 60% location; the width of each safe zone was 13.6° ± 1.4°; the maximum height of each safe zone was 7.8° ± 1.2°. The height of the safe zone was lowest at the 30% location (4.5°) and highest at the 50% location (7.3°). The mixed safe zone of all tali was between the 50% location and the 60% location. When a screw was inserted at point a, the safe entry distance (screw length) ranged from 48.8 to 49.5 mm, and when inserted to point b, the distance ranged from 48.2 to 48.9 mm. And inserting a 48.7 mm screw, 5.6° laterally and 7.4° superiorly, from the lateral tubercle of the posterior process of the talus towards the talar head is safest. The safe zone of posterior screw fixation have been defined applying to most talus, assuming the fractures are well reduced, this may strengthen the stability, shorten the operation time and reduce the incidence of surgical complications. © 2017 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

  8. Black-hole evaporation and ultrashort distances

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jacobson, T.

    1991-09-15

    The role played by ultrahigh frequencies of ultrashort distances in the usual derivations of the Hawking effect is discussed and criticized. The question would a blackhole radiate if there were a Planck scale cutoff in the rest frame of the hole '' is posed. Guidance is sought from Unruh's fluid-flow analogue of black-hole radiation, by taking into account the atomic nature of the fluid. Two arguments for black-hole radiation are given which assume a Planck length cutoff. One involves the response of static accelerated detectors outside the horizon, and the other involves conservation of the expectation value of the stressmore » tensor. Neither argument is conclusive, but they do strongly suggest that, in spite of reasonable doubt about the usual derivations of black-hole radiation, a safe'' derivation which avoids our ignorance of ultrashort-distance physics can likely be formulated. Remaining open questions are discussed.« less

  9. Determination of safety distance limits for a human near a cellular base station antenna, adopting the IEEE standard or ICNIRP guidelines.

    PubMed

    Cooper, Justin; Marx, Bernd; Buhl, Johannes; Hombach, Volker

    2002-09-01

    This paper investigates the minimum distance for a human body in the near field of a cellular telephone base station antenna for which there is compliance with the IEEE or ICNIRP threshold values for radio frequency electromagnetic energy absorption in the human body. First, local maximum specific absorption rates (SARs), measured and averaged over volumes equivalent to 1 and to 10 g tissue within the trunk region of a physical, liquid filled shell phantom facing and irradiated by a typical GSM 900 base station antenna, were compared to corresponding calculated SAR values. The calculation used a homogeneous Visible Human body model in front of a simulated base station antenna of the same type. Both real and simulated base station antennas operated at 935 MHz. Antenna-body distances were between 1 and 65 cm. The agreement between measurements and calculations was excellent. This gave confidence in the subsequent calculated SAR values for the heterogeneous Visible Human model, for which each tissue was assigned the currently accepted values for permittivity and conductivity at 935 MHz. Calculated SAR values within the trunk of the body were found to be about double those for the homogeneous case. When the IEEE standard and the ICNIRP guidelines are both to be complied with, the local SAR averaged over 1 g tissue was found to be the determining parameter. Emitted power values from the antenna that produced the maximum SAR value over 1 g specified in the IEEE standard at the base station are less than those needed to reach the ICNIRP threshold specified for the local SAR averaged over 10 g. For the GSM base station antenna investigated here operating at 935 MHz with 40 W emitted power, the model indicates that the human body should not be closer to the antenna than 18 cm for controlled environment exposure, or about 95 cm for uncontrolled environment exposure. These safe distance limits are for SARs averaged over 1 g tissue. The corresponding safety distance limits

  10. A method of calculating the safe fatigue life of compact, highly-stressed components

    NASA Technical Reports Server (NTRS)

    Cardick, Arthur W.; Pike, Vera J.

    1994-01-01

    This paper describes a method which has been developed for estimating the safe fatigue life of compact, highly-stressed and inaccessible components for aeroplanes and helicopters of the Royal Air Force. It is explained why the Design Requirements for British Military Aircraft do not favor the use of a damage-tolerance approach in these circumstances.

  11. Stopping Distances: An Excellent Example of Empirical Modelling.

    ERIC Educational Resources Information Center

    Lawson, D. A.; Tabor, J. H.

    2001-01-01

    Explores the derivation of empirical models for the stopping distance of a car being driven at a range of speeds. Indicates that the calculation of stopping distances makes an excellent example of empirical modeling because it is a situation that is readily understood and particularly relevant to many first-year undergraduates who are learning or…

  12. Measuring genetic distances between breeds: use of some distances in various short term evolution models

    PubMed Central

    Laval, Guillaume; SanCristobal, Magali; Chevalet, Claude

    2002-01-01

    Many works demonstrate the benefits of using highly polymorphic markers such as microsatellites in order to measure the genetic diversity between closely related breeds. But it is sometimes difficult to decide which genetic distance should be used. In this paper we review the behaviour of the main distances encountered in the literature in various divergence models. In the first part, we consider that breeds are populations in which the assumption of equilibrium between drift and mutation is verified. In this case some interesting distances can be expressed as a function of divergence time, t, and therefore can be used to construct phylogenies. Distances based on allele size distribution (such as (δμ)2 and derived distances), taking a mutation model of microsatellites, the Stepwise Mutation Model, specifically into account, exhibit large variance and therefore should not be used to accurately infer phylogeny of closely related breeds. In the last section, we will consider that breeds are small populations and that the divergence times between them are too small to consider that the observed diversity is due to mutations: divergence is mainly due to genetic drift. Expectation and variance of distances were calculated as a function of the Wright-Malécot inbreeding coefficient, F. Computer simulations performed under this divergence model show that the Reynolds distance [57]is the best method for very closely related breeds. PMID:12270106

  13. Readability of Distance Education Course Material.

    ERIC Educational Resources Information Center

    Mouli, C. Raja; Ramakrishna, C. Pushpa

    1991-01-01

    Flesch Reading Ease scores were calculated for 48 books used in distance education courses at Andhra Pradesh Open University (India). Scores ranged from 32 (public administration) to 46 (geology). Scores correlated positively with pass percentages. (SK)

  14. Measuring Distance of Fuzzy Numbers by Trapezoidal Fuzzy Numbers

    NASA Astrophysics Data System (ADS)

    Hajjari, Tayebeh

    2010-11-01

    Fuzzy numbers and more generally linguistic values are approximate assessments, given by experts and accepted by decision-makers when obtaining value that is more accurate is impossible or unnecessary. Distance between two fuzzy numbers plays an important role in linguistic decision-making. It is reasonable to define a fuzzy distance between fuzzy objects. To achieve this aim, the researcher presents a new distance measure for fuzzy numbers by means of improved centroid distance method. The metric properties are also studied. The advantage is the calculation of the proposed method is far simple than previous approaches.

  15. Calculating distance by wireless ethernet signal strength for global positioning method

    NASA Astrophysics Data System (ADS)

    Kim, Seung-Yong; Kim, Jeehong; Lee, Chang-goo

    2005-12-01

    This paper investigated mobile robot localization by using wireless Ethernet for global localization and INS for relative localization. For relative localization, the low-cost INS features self-contained was adopted. Low-cost MEMS-based INS has a short-period response and acceptable performance. Generally, variety sensor was used for mobile robot localization. In spite of precise modeling of the sensor, it leads inevitably to the accumulation of errors. The IEEE802.11b wireless Ethernet standard has been deployed in office building, museums, hospitals, shopping centers and other indoor environments. Many mobile robots already make use of wireless networking for communication. So location sensing with wireless Ethernet might be very useful for a low-cost robot. This research used wireless Ethernet card for compensation the accumulation of errors. So the mobile robot can use that for global localization through the installed many IEEE802.11b wireless Ethernets in indoor environments. The chief difficulty in localization with wireless Ethernet is predicting signal strength. As a sensor, RF signal strength measured indoors is non-linear with distance. So, there made the profiles of signal strength for points and used that. We wrote using function between signal strength profile and distance from the wireless Ethernet point.

  16. DISTANCES TO DARK CLOUDS: COMPARING EXTINCTION DISTANCES TO MASER PARALLAX DISTANCES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Foster, Jonathan B.; Jackson, James M.; Stead, Joseph J.

    We test two different methods of using near-infrared extinction to estimate distances to dark clouds in the first quadrant of the Galaxy using large near-infrared (Two Micron All Sky Survey and UKIRT Infrared Deep Sky Survey) surveys. Very long baseline interferometry parallax measurements of masers around massive young stars provide the most direct and bias-free measurement of the distance to these dark clouds. We compare the extinction distance estimates to these maser parallax distances. We also compare these distances to kinematic distances, including recent re-calibrations of the Galactic rotation curve. The extinction distance methods agree with the maser parallax distancesmore » (within the errors) between 66% and 100% of the time (depending on method and input survey) and between 85% and 100% of the time outside of the crowded Galactic center. Although the sample size is small, extinction distance methods reproduce maser parallax distances better than kinematic distances; furthermore, extinction distance methods do not suffer from the kinematic distance ambiguity. This validation gives us confidence that these extinction methods may be extended to additional dark clouds where maser parallaxes are not available.« less

  17. Safe speed limits for a safe system: The relationship between speed limit and fatal crash rate for different crash types.

    PubMed

    Doecke, Sam D; Kloeden, Craig N; Dutschke, Jeffrey K; Baldock, Matthew R J

    2018-05-19

    The objective of this article is to provide empirical evidence for safe speed limits that will meet the objectives of the Safe System by examining the relationship between speed limit and injury severity for different crash types, using police-reported crash data. Police-reported crashes from 2 Australian jurisdictions were used to calculate a fatal crash rate by speed limit and crash type. Example safe speed limits were defined using threshold risk levels. A positive exponential relationship between speed limit and fatality rate was found. For an example fatality rate threshold of 1 in 100 crashes it was found that safe speed limits are 40 km/h for pedestrian crashes; 50 km/h for head-on crashes; 60 km/h for hit fixed object crashes; 80 km/h for right angle, right turn, and left road/rollover crashes; and 110 km/h or more for rear-end crashes. The positive exponential relationship between speed limit and fatal crash rate is consistent with prior research into speed and crash risk. The results indicate that speed zones of 100 km/h or more only meet the objectives of the Safe System, with regard to fatal crashes, where all crash types except rear-end crashes are exceedingly rare, such as on a high standard restricted access highway with a safe roadside design.

  18. Braking distance algorithm for autonomous cars using road surface recognition

    NASA Astrophysics Data System (ADS)

    Kavitha, C.; Ashok, B.; Nanthagopal, K.; Desai, Rohan; Rastogi, Nisha; Shetty, Siddhanth

    2017-11-01

    India is yet to accept semi/fully - autonomous cars and one of the reasons, was loss of control on bad roads. For a better handling on these roads we require advanced braking and that can be done by adapting electronics into the conventional type of braking. In Recent years, the automation in braking system led us to various benefits like traction control system, anti-lock braking system etc. This research work describes and experiments the method for recognizing road surface profile and calculating braking distance. An ultra-sonic surface recognition sensor, mounted underneath the car will send a high frequency wave on to the road surface, which is received by a receiver with in the sensor, it calculates the time taken for the wave to rebound and thus calculates the distance from the point where sensor is mounted. A displacement graph will be plotted based on the output of the sensor. A relationship can be derived between the displacement plot and roughness index through which the friction coefficient can be derived in Matlab for continuous calculation throughout the distance travelled. Since it is a non-contact type of profiling, it is non-destructive. The friction coefficient values received in real-time is used to calculate optimum braking distance. This system, when installed on normal cars can also be used to create a database of road surfaces, especially in cities, which can be shared with other cars. This will help in navigation as well as making the cars more efficient.

  19. Safety in numbers 3: Authenticity, Building knowledge & skills and Competency development & assessment: the ABC of safe medication dosage calculation problem-solving pedagogy.

    PubMed

    Weeks, Keith W; Meriel Hutton, B; Coben, Diana; Clochesy, John M; Pontin, David

    2013-03-01

    When designing learning and assessment environments it is essential to articulate the underpinning education philosophy, theory, model and learning style support mechanisms that inform their structure and content. We elaborate on original PhD research that articulates the design rationale of authentic medication dosage calculation problem-solving (MDC-PS) learning and diagnostic assessment environments. These environments embody the principles of authenticity, building knowledge and skills and competency assessment and are designed to support development of competence and bridging of the theory-practice gap. Authentic learning and diagnostic assessment environments capture the features and expert practices that are located in real world practice cultures and recreate them in authentic virtual clinical environments. We explore how this provides students with a safe virtual authentic environment to actively experience, practice and undertake MDC-PS learning and assessment activities. We argue that this is integral to the construction and diagnostic assessment of schemata validity (mental constructions and frameworks that are an individual's internal representation of their world), bridging of the theory-practice gap and cognitive and functional competence development. We illustrate these principles through the underpinning pedagogical design of two online virtual authentic learning and diagnostic assessment environments (safeMedicate and eDose™). Copyright © 2012. Published by Elsevier Ltd.

  20. Detecting duplicate biological entities using Shortest Path Edit Distance.

    PubMed

    Rudniy, Alex; Song, Min; Geller, James

    2010-01-01

    Duplicate entity detection in biological data is an important research task. In this paper, we propose a novel and context-sensitive Shortest Path Edit Distance (SPED) extending and supplementing our previous work on Markov Random Field-based Edit Distance (MRFED). SPED transforms the edit distance computational problem to the calculation of the shortest path among two selected vertices of a graph. We produce several modifications of SPED by applying Levenshtein, arithmetic mean, histogram difference and TFIDF techniques to solve subtasks. We compare SPED performance to other well-known distance algorithms for biological entity matching. The experimental results show that SPED produces competitive outcomes.

  1. Generalising Ward's Method for Use with Manhattan Distances.

    PubMed

    Strauss, Trudie; von Maltitz, Michael Johan

    2017-01-01

    The claim that Ward's linkage algorithm in hierarchical clustering is limited to use with Euclidean distances is investigated. In this paper, Ward's clustering algorithm is generalised to use with l1 norm or Manhattan distances. We argue that the generalisation of Ward's linkage method to incorporate Manhattan distances is theoretically sound and provide an example of where this method outperforms the method using Euclidean distances. As an application, we perform statistical analyses on languages using methods normally applied to biology and genetic classification. We aim to quantify differences in character traits between languages and use a statistical language signature based on relative bi-gram (sequence of two letters) frequencies to calculate a distance matrix between 32 Indo-European languages. We then use Ward's method of hierarchical clustering to classify the languages, using the Euclidean distance and the Manhattan distance. Results obtained from using the different distance metrics are compared to show that the Ward's algorithm characteristic of minimising intra-cluster variation and maximising inter-cluster variation is not violated when using the Manhattan metric.

  2. 47 CFR 73.6008 - Distance computations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Distance computations. 73.6008 Section 73.6008 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES... reference points must be calculated in accordance with § 73.208(c) of this part. ...

  3. A Critical Interpersonal Distance Switches between Two Coordination Modes in Kendo Matches

    PubMed Central

    Okumura, Motoki; Kijima, Akifumi; Kadota, Koji; Yokoyama, Keiko; Suzuki, Hiroo; Yamamoto, Yuji

    2012-01-01

    In many competitive sports, players need to quickly and continuously execute movements that co-adapt to various movements executed by their opponents and physical objects. In a martial art such as kendo, players must be able to skillfully change interpersonal distance in order to win. However, very little information about the task and expertise properties of the maneuvers affecting interpersonal distance is available. This study investigated behavioral dynamics underlying opponent tasks by analyzing changes in interpersonal distance made by expert players in kendo matches. Analysis of preferred interpersonal distances indicated that players tended to step toward and away from their opponents based on two distances. The most preferred distance enabled the players to execute both striking and defensive movements immediately. The relative phase analysis of the velocities at which players executed steps toward and away revealed that players developed anti-phase synchronizations at near distances to maintain safe distances from their opponents. Alternatively, players shifted to in-phase synchronization to approach their opponents from far distances. This abrupt phase-transition phenomenon constitutes a characteristic bifurcation dynamics that regularly and instantaneously occurs between in- and anti-phase synchronizations at a critical interpersonal distance. These dynamics are profoundly affected by the task constraints of kendo and the physical constraints of the players. Thus, the current study identifies the clear behavioral dynamics that emerge in a sport setting. PMID:23284799

  4. Time resolved small angle X-ray scattering experiments performed on detonating explosives at the advanced photon source: Calculation of the time and distance between the detonation front and the x-ray beam

    DOE PAGES

    Gustavsen, Richard L.; Dattelbaum, Dana Mcgraw; Watkins, Erik Benjamin; ...

    2017-03-10

    Time resolved Small Angle X-ray Scattering (SAXS) experiments on detonating explosives have been conducted at Argonne National Laboratory's Advanced Photon Source Dynamic Compression Sector. The purpose of the experiments is to measure the SAXS patterns at tens of ns to a few μs behind the detonation front. Corresponding positions behind the detonation front are of order 0.1–10 mm. From the scattering patterns, properties of the explosive products relative to the time behind the detonation front can be inferred. Lastly, this report describes how the time and distance from the x-ray probe location to the detonation front is calculated, as wellmore » as the uncertainties and sources of uncertainty associated with the calculated times and distances.« less

  5. Time resolved small angle X-ray scattering experiments performed on detonating explosives at the advanced photon source: Calculation of the time and distance between the detonation front and the x-ray beam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gustavsen, Richard L.; Dattelbaum, Dana Mcgraw; Watkins, Erik Benjamin

    Time resolved Small Angle X-ray Scattering (SAXS) experiments on detonating explosives have been conducted at Argonne National Laboratory's Advanced Photon Source Dynamic Compression Sector. The purpose of the experiments is to measure the SAXS patterns at tens of ns to a few μs behind the detonation front. Corresponding positions behind the detonation front are of order 0.1–10 mm. From the scattering patterns, properties of the explosive products relative to the time behind the detonation front can be inferred. Lastly, this report describes how the time and distance from the x-ray probe location to the detonation front is calculated, as wellmore » as the uncertainties and sources of uncertainty associated with the calculated times and distances.« less

  6. Measuring Distances Using Digital Cameras

    ERIC Educational Resources Information Center

    Kendal, Dave

    2007-01-01

    This paper presents a generic method of calculating accurate horizontal and vertical object distances from digital images taken with any digital camera and lens combination, where the object plane is parallel to the image plane or tilted in the vertical plane. This method was developed for a project investigating the size, density and spatial…

  7. Scalable parallel distance field construction for large-scale applications

    DOE PAGES

    Yu, Hongfeng; Xie, Jinrong; Ma, Kwan -Liu; ...

    2015-10-01

    Computing distance fields is fundamental to many scientific and engineering applications. Distance fields can be used to direct analysis and reduce data. In this paper, we present a highly scalable method for computing 3D distance fields on massively parallel distributed-memory machines. Anew distributed spatial data structure, named parallel distance tree, is introduced to manage the level sets of data and facilitate surface tracking overtime, resulting in significantly reduced computation and communication costs for calculating the distance to the surface of interest from any spatial locations. Our method supports several data types and distance metrics from real-world applications. We demonstrate itsmore » efficiency and scalability on state-of-the-art supercomputers using both large-scale volume datasets and surface models. We also demonstrate in-situ distance field computation on dynamic turbulent flame surfaces for a petascale combustion simulation. In conclusion, our work greatly extends the usability of distance fields for demanding applications.« less

  8. Scalable Parallel Distance Field Construction for Large-Scale Applications.

    PubMed

    Yu, Hongfeng; Xie, Jinrong; Ma, Kwan-Liu; Kolla, Hemanth; Chen, Jacqueline H

    2015-10-01

    Computing distance fields is fundamental to many scientific and engineering applications. Distance fields can be used to direct analysis and reduce data. In this paper, we present a highly scalable method for computing 3D distance fields on massively parallel distributed-memory machines. A new distributed spatial data structure, named parallel distance tree, is introduced to manage the level sets of data and facilitate surface tracking over time, resulting in significantly reduced computation and communication costs for calculating the distance to the surface of interest from any spatial locations. Our method supports several data types and distance metrics from real-world applications. We demonstrate its efficiency and scalability on state-of-the-art supercomputers using both large-scale volume datasets and surface models. We also demonstrate in-situ distance field computation on dynamic turbulent flame surfaces for a petascale combustion simulation. Our work greatly extends the usability of distance fields for demanding applications.

  9. Medication calculation and administration workshop and hurdle assessment increases student awareness towards the importance of safe practices to decrease medication errors in the future.

    PubMed

    Wallace, Darlene; Woolley, Torres; Martin, David; Rasalam, Roy; Bellei, Maria

    2016-01-01

    Medication errors are the second most frequently reported hospital incident in Australia and are a global concern. A "Medication Calculation and Administration" workshop followed by a "hurdle" assessment (compulsory task mandating a minimum level of performance as a condition of passing the course) was introduced into Year 2 of the James Cook University medical curriculum to decrease dosage calculation and administration errors among graduates. This study evaluates the effectiveness of this educational activity as a long-term strategy to teach medical students' essential skills in calculating and administering medications. This longitudinal study used a pre- and post-test design to determine whether medical students retained their calculation and administration skills over a period of 4 years. The ability to apply basic mathematical skills to medication dose calculation, principles of safe administration (Part 1), and ability to access reference materials to check indications, contraindications, and writing the medication order with correct abbreviations (Part 2) were compared between Year 2 and 6 assessments. Scores for Parts 1, 2 and total scores were nearly identical from Year 2 to Year 6 (P = 0.663, 0.408, and 0.472, respectively), indicating minimal loss of knowledge by students in this period. Most Year 6 students (86%) were able to recall at least 5 of the "6 Rights of Medication Administration" while 84% reported accessing reference material and 91% reported checking their medical calculations. The "Medication Calculation and Administration" workshop with a combined formative and summative assessment - a "hurdle" - promotes long-term retention of essential clinical skills for medical students. These skills and an awareness of the problem are strategies to assist medical graduates in preventing future medication-related adverse events.

  10. Use of a 3-D Dispersion Model for Calculation of Distribution of Horse Allergen and Odor around Horse Facilities

    PubMed Central

    Haeger-Eugensson, Marie; Ferm, Martin; Elfman, Lena

    2014-01-01

    The interest in equestrian sports has increased substantially during the last decades, resulting in increased number of horse facilities around urban areas. In Sweden, new guidelines for safe distance have been decided based on the size of the horse facility (e.g., number of horses) and local conditions, such as topography and meteorology. There is therefore an increasing need to estimate dispersion of horse allergens to be used, for example, in the planning processes for new residential areas in the vicinity of horse facilities. The aim of this study was to develop a method for calculating short- and long-term emissions and dispersion of horse allergen and odor around horse facilities. First, a method was developed to estimate horse allergen and odor emissions at hourly resolution based on field measurements. Secondly, these emission factors were used to calculate concentrations of horse allergen and odor by using 3-D dispersion modeling. Results from these calculations showed that horse allergens spread up to about 200 m, after which concentration levels were very low (<2 U/m3). Approximately 10% of a study-group detected the smell of manure at 60m, while the majority—80%–90%—detected smell at 60 m or shorter distance from the manure heap. Modeling enabled horse allergen exposure concentrations to be determined with good time resolution. PMID:24690946

  11. Distance between configurations in Markov chain Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Fukuma, Masafumi; Matsumoto, Nobuyuki; Umeda, Naoya

    2017-12-01

    For a given Markov chain Monte Carlo algorithm we introduce a distance between two configurations that quantifies the difficulty of transition from one configuration to the other configuration. We argue that the distance takes a universal form for the class of algorithms which generate local moves in the configuration space. We explicitly calculate the distance for the Langevin algorithm, and show that it certainly has desired and expected properties as distance. We further show that the distance for a multimodal distribution gets dramatically reduced from a large value by the introduction of a tempering method. We also argue that, when the original distribution is highly multimodal with large number of degenerate vacua, an anti-de Sitter-like geometry naturally emerges in the extended configuration space.

  12. Distance dependence in photoinduced intramolecular electron transfer. Additional remarks and calculations

    NASA Astrophysics Data System (ADS)

    Larsson, Sven; Volosov, Andrey

    1987-12-01

    Rate constants for photoinduced intramolecular electron transfer are calculated for four of the molecules studied by Hush et al. The electronic factor is obtained in quantum chemical calculations using the CNDO/S method. The results agree reasonably well with experiments for the forward reaction. Possible reasons for the disagreement for the charge recombination process are offered.

  13. Safe motherhood partners -- the International Children's Centre.

    PubMed

    1994-01-01

    The International Children's Centre (ICC) works worldwide to improve child health in the least developed countries. In its training and research projects the agency contributes to the Safe Motherhood Initiative to improve the health of mothers and infants. ICC is based in Paris, it was established in 1949, and the agency has cooperated with governments, nongovernmental organizations and international bodies like the World Health Organization (WHO) in child care. ICC's activities reflect concern for the health of women before and during pregnancy and the rest of their lives. The center's work comprises training, research, local projects, and information and documentation. Following the 1987 Nairobi conference on safe motherhood, ICC organized a seminar in Paris on maternal mortality in Sub-Saharan francophone Africa, which led to participation in the Safe Motherhood Initiative with a variety of training and research programs. ICC training is integrated, community-based, and multidisciplinary. Anthropology, psychology, economics and management have played a role in ICC training courses. The center runs an international course on maternal and child health from January to April each year and also organizes distance training courses on problem solving in health care. ICC training programs have taken place in Laos, Senegal, and Vietnam to strengthen the work of maternal and child health training centers there. A 4-week course on economic evaluation of health programs is held in Paris each July. In 1989 and 1990, ICC organized in collaboration with WHO safe motherhood workshops on research methodology in Benin and in Burkina Faso with participants from 6 francophone African countries. One research project in Benin is on risk factors for maternal and perinatal mortality and morbidity, and the other in Cameroon on improving surveillance of pregnancy, delivery, and the postnatal period. ICC focuses on long-term planning and action for the benefit of mothers and children.

  14. Precise Distances for Main-belt Asteroids in Only Two Nights

    NASA Astrophysics Data System (ADS)

    Heinze, Aren N.; Metchev, Stanimir

    2015-10-01

    We present a method for calculating precise distances to asteroids using only two nights of data from a single location—far too little for an orbit—by exploiting the angular reflex motion of the asteroids due to Earth’s axial rotation. We refer to this as the rotational reflex velocity method. While the concept is simple and well-known, it has not been previously exploited for surveys of main belt asteroids (MBAs). We offer a mathematical development, estimates of the errors of the approximation, and a demonstration using a sample of 197 asteroids observed for two nights with a small, 0.9-m telescope. This demonstration used digital tracking to enhance detection sensitivity for faint asteroids, but our distance determination works with any detection method. Forty-eight asteroids in our sample had known orbits prior to our observations, and for these we demonstrate a mean fractional error of only 1.6% between the distances we calculate and those given in ephemerides from the Minor Planet Center. In contrast to our two-night results, distance determination by fitting approximate orbits requires observations spanning 7-10 nights. Once an asteroid’s distance is known, its absolute magnitude and size (given a statistically estimated albedo) may immediately be calculated. Our method will therefore greatly enhance the efficiency with which 4m and larger telescopes can probe the size distribution of small (e.g., 100 m) MBAs. This distribution remains poorly known, yet encodes information about the collisional evolution of the asteroid belt—and hence the history of the Solar System.

  15. A New Distance Metric for Unsupervised Learning of Categorical Data.

    PubMed

    Jia, Hong; Cheung, Yiu-Ming; Liu, Jiming

    2016-05-01

    Distance metric is the basis of many learning algorithms, and its effectiveness usually has a significant influence on the learning results. In general, measuring distance for numerical data is a tractable task, but it could be a nontrivial problem for categorical data sets. This paper, therefore, presents a new distance metric for categorical data based on the characteristics of categorical values. In particular, the distance between two values from one attribute measured by this metric is determined by both the frequency probabilities of these two values and the values of other attributes that have high interdependence with the calculated one. Dynamic attribute weight is further designed to adjust the contribution of each attribute-distance to the distance between the whole data objects. Promising experimental results on different real data sets have shown the effectiveness of the proposed distance metric.

  16. Cool and Safe: Multiplicity in Safe Innovation at Unilever

    ERIC Educational Resources Information Center

    Penders, Bart

    2011-01-01

    This article presents the making of a safe innovation: the application of ice structuring protein (ISP) in edible ices. It argues that safety is not the absence of risk but is an active accomplishment; innovations are not "made safe afterward" but "safe innovations are made". Furthermore, there are multiple safeties to be accomplished in the…

  17. Anatomical consideration of the occipital cutaneous nerves and artery for the safe treatment of occipital neuralgia.

    PubMed

    Shin, Kang-Jae; Kim, Hong-San; O, Jehoon; Kwon, Hyun-Jin; Yang, Hun-Mu

    2018-05-12

    There is no standardized approach to the greater occipital nerve (GON) block technique for treating occipital neuralgia. The aim of the present study was to validate the previously-suggested guidelines for conventional injection techniques and to provide navigational guidelines for safe GON block. The GON, lesser occipital nerve (LON) and occipital artery (OA) were carefully dissected in the occipital region of embalmed cadavers. Using a 3D digitizer, the GON, LON, and OA were observed on the two reference lines. The distances between the landmarks were recorded and statistically analyzed. On the superior nuchal line, the mean distances between the external occipital protuberance (EOP) and the most medial branch of the GON was 33.5 mm. The mean distance between the EOP and the most medial branch of the OA was 37.4 mm. On the EOP-mastoid process (MP) line, the GON was on the medial third and the LON the lateral third of the EOP-MP line. The safe injection points on the EOP-MP line are about 3 cm from the EOP, 1 cm inferior parallel to the EOP-MP line, and about 3 cm away from the MP. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  18. Dosage calculations for nurses June L Olsen Dosage calculations for nurses et al Pearson Education £14.99 312pp 9780132068840 0132068842 [Formula: see text].

    PubMed

    2011-05-10

    A COMPREHENSIVE review of dosage calculation for nursing staff, this covers accurate calculation skills and interpretation of units of measurement in the context of safe medication-administration practice.

  19. Robotic long-distance telementoring in neurosurgery.

    PubMed

    Mendez, Ivar; Hill, Ron; Clarke, David; Kolyvas, George; Walling, Simon

    2005-03-01

    To test the feasibility of long-distance telementoring in neurosurgery by providing subspecialized expertise in real time to another neurosurgeon performing a surgical procedure in a remote location. A robotic telecollaboration system (Socrates; Computer Motion, Inc., Santa Barbara, CA) capable of controlling the movements of a robotic arm, of handling two-way video, and of audio communication as well as transmission of neuronavigational data from the remote operating room was used for the telementoring procedures. Four integrated services digital network lines with a total speed of transmission of 512 kilobytes per second provided telecommunications between a large academic center (Halifax, Nova Scotia) and a community-based center (Saint John, New Brunswick) located 400 km away. Long-distance telementoring was used in three craniotomies for brain tumors, a craniotomy for an arteriovenous malformation, a carotid endarterectomy, and a lumbar laminectomy. There were no surgical complications during the procedures, and all patients had uneventful outcomes. The neurosurgeons in the remote location believed that the input from the mentors was useful in all of the cases and was crucial in the removal of a mesial temporal lobe glioma and resection of an occipital arteriovenous malformation. Our initial experience with long-distance robotic-assisted telementoring in six cases indicates that telementoring is feasible, reliable, and safe. Although still in its infancy, telementoring has the potential to improve surgical care, to enhance neurosurgical training, and to have a major impact on the delivery of neurosurgical services throughout the world.

  20. [Safe school].

    PubMed

    Liberal, Edson Ferreira; Aires, Roberto Tschoepke; Aires, Mariana Tschoepke; Osório, Ana Carla de Albuquerque

    2005-11-01

    To review the strategies to make school a safe environment. The paper first addresses the social context of accidents and violence in the school environment, and makes recommendations, based on the literature data, for the implementation of safe schools. Articles published between 1993 and 2005 in the MEDLINE database. Brazilian epidemiological and literature data have also been searched. There is growing evidence that intervention has multiple components, focusing on health education practices, with the participation of the whole community. The aim of those interventions is to help students and community members to adopt healthy and safe behaviors. Schools are taking on an increasing role in health promotion, disease prevention, and injury prevention. In the context of prevention of external causes of morbidity and mortality, it is important to recognize a risky environment, places, and risk behaviors as favorable to injury and violence, as well as the concept of accident as something one can avoid. Implementation of safe schools represents a promising new direction for school-based preventive work. It is important to note that a safe school should intervene not only in its physical structure, but it should also make it as safe as possible by gathering the school community through health education, and mainly encouraging healthy behavior.

  1. Development of LIDAR sensor systems for autonomous safe landing on planetary bodies

    NASA Astrophysics Data System (ADS)

    Amzajerdian, F.; Pierrottet, D.; Petway, L.; Vanek, M.

    2017-11-01

    Future NASA exploratory missions to the Moon and Mars will require safe soft-landings at the designated sites with a high degree of precision. These sites may include areas of high scientific value with relatively rough terrain with little or no solar illumination and possibly areas near pre-deployed assets. The ability of lidar technology to provide three-dimensional elevation maps of the terrain, high precision distance to the ground, and approach velocity can enable safe landing of large robotic and manned vehicles with a high degree of precision. Currently, NASA-LaRC is developing novel lidar sensors aimed at meeting NASA's objectives for future planetary landing missions under the Autonomous Landing and Hazard Avoidance (ALHAT) project. These lidar sensors are 3-Dimensional Imaging Flash Lidar, Doppler Lidar, and Laser Altimeter. The Flash Lidar is capable of generating elevation maps of the terrain identifying hazardous features such as rocks, craters, and steep slopes. The elevation maps collected during the approach phase between 1000 m to 500 m above the ground can be used to determine the most suitable safe landing site. The Doppler Lidar provides highly accurate ground velocity and distance data allowing for precision navigation to the selected landing site. Prior to the approach phase at altitudes of over 15 km, the Laser Altimeter can provide sufficient data for updating the vehicle position and attitude data from the Inertial Measurement Unit. At these higher altitudes, either the Laser Altimeter or the Flash Lidar can be used for generating a contour map of the terrain below for identifying known surface features such as craters for further reducing the vehicle relative position error.

  2. Development of lidar sensor systems for autonomous safe landing on planetary bodies

    NASA Astrophysics Data System (ADS)

    Amzajerdian, F.; Pierrottet, D.; Petway, L.; Vanek, M.

    2017-11-01

    Future NASA exploratory missions to the Moon and Mars will require safe soft-landings at the designated sites with a high degree of precision. These sites may include areas of high scientific value with relatively rough terrain with little or no solar illumination and possibly areas near pre-deployed assets. The ability of lidar technology to provide three-dimensional elevation maps of the terrain, high precision distance to the ground, and approach velocity can enable safe landing of large robotic and manned vehicles with a high degree of precision. Currently, NASA-LaRC is developing novel lidar sensors aimed at meeting NASA's objectives for future planetary landing missions under the Autonomous Landing and Hazard Avoidance (ALHAT) project [1]. These lidar sensors are 3-Dimensional Imaging Flash Lidar, Doppler Lidar, and Laser Altimeter. The Flash Lidar is capable of generating elevation maps of the terrain identifying hazardous features such as rocks, craters, and steep slopes. The elevation maps collected during the approach phase between 1000 m to 500 m above the ground can be used to determine the most suitable safe landing site. The Doppler Lidar provides highly accurate ground velocity and distance data allowing for precision navigation to the selected landing site. Prior to the approach phase at altitudes of over 15 km, the Laser Altimeter can provide sufficient data for updating the vehicle position and attitude data from the Inertial Measurement Unit. At these higher altitudes, either the Laser Altimeter or the Flash Lidar can be used for generating a contour map of the terrain below for identifying known surface features such as craters for further reducing the vehicle relative position error.

  3. Exploring the Use of Electronic Mobile Technologies among Distance Learners in Rural Communities for Safe and Disruptive Learning

    ERIC Educational Resources Information Center

    Ntloedibe-Kuswani, Gomang Seratwa

    2013-01-01

    Several studies indicated the potential of electronic mobile technologies in reaching (safe learning) under-served communities and engaging (disruptive learning) disadvantaged peoples affording them learning experiences. However, the potential benefits of (electronic mobile learning) e-mobile learning have not been well understood from the…

  4. Adaptive density trajectory cluster based on time and space distance

    NASA Astrophysics Data System (ADS)

    Liu, Fagui; Zhang, Zhijie

    2017-10-01

    There are some hotspot problems remaining in trajectory cluster for discovering mobile behavior regularity, such as the computation of distance between sub trajectories, the setting of parameter values in cluster algorithm and the uncertainty/boundary problem of data set. As a result, based on the time and space, this paper tries to define the calculation method of distance between sub trajectories. The significance of distance calculation for sub trajectories is to clearly reveal the differences in moving trajectories and to promote the accuracy of cluster algorithm. Besides, a novel adaptive density trajectory cluster algorithm is proposed, in which cluster radius is computed through using the density of data distribution. In addition, cluster centers and number are selected by a certain strategy automatically, and uncertainty/boundary problem of data set is solved by designed weighted rough c-means. Experimental results demonstrate that the proposed algorithm can perform the fuzzy trajectory cluster effectively on the basis of the time and space distance, and obtain the optimal cluster centers and rich cluster results information adaptably for excavating the features of mobile behavior in mobile and sociology network.

  5. Numerical calculation of the Fresnel transform.

    PubMed

    Kelly, Damien P

    2014-04-01

    In this paper, we address the problem of calculating Fresnel diffraction integrals using a finite number of uniformly spaced samples. General and simple sampling rules of thumb are derived that allow the user to calculate the distribution for any propagation distance. It is shown how these rules can be extended to fast-Fourier-transform-based algorithms to increase calculation efficiency. A comparison with other theoretical approaches is made.

  6. Exact geodesic distances in FLRW spacetimes

    NASA Astrophysics Data System (ADS)

    Cunningham, William J.; Rideout, David; Halverson, James; Krioukov, Dmitri

    2017-11-01

    Geodesics are used in a wide array of applications in cosmology and astrophysics. However, it is not a trivial task to efficiently calculate exact geodesic distances in an arbitrary spacetime. We show that in spatially flat (3 +1 )-dimensional Friedmann-Lemaître-Robertson-Walker (FLRW) spacetimes, it is possible to integrate the second-order geodesic differential equations, and derive a general method for finding both timelike and spacelike distances given initial-value or boundary-value constraints. In flat spacetimes with either dark energy or matter, whether dust, radiation, or a stiff fluid, we find an exact closed-form solution for geodesic distances. In spacetimes with a mixture of dark energy and matter, including spacetimes used to model our physical universe, there exists no closed-form solution, but we provide a fast numerical method to compute geodesics. A general method is also described for determining the geodesic connectedness of an FLRW manifold, provided only its scale factor.

  7. Determination of safe margin in the surgical pathologic specimens of non-small cell carcinoma of the lung.

    PubMed

    Feizi, Iraj; Sokouti, Mohsen; Golzari, Samad E J; Gojazede, Morteza; Farahnak, Mohammad Reza; Hashemzadeh, Shahriar; Rahimi-Rad, Mohammad Hossein

    2013-01-01

    Local recurrences of the tumor at the surgical margin are serious problems in pulmonary resections for lung cancer. The aim of this study is to determine the involved margins and safe distances of the resection sites from tumor for prevention of local recurrences. In this prospective study, 66 patients operated for non-small cell lung carcinoma (NSCLC) from Jan 2006 to Sep 2008 were evaluated. After performing pulmonary resections, multiple biopsies were taken up from 5 mm (A), 10 mm (B), 15 mm (C), and 20 mm (D) distance from tumor. The specimens were studied histopathologically. From a total of66 patients with NSCLC admitted to our referral hospital, 25 (38%) had adenocarcinoma, 18 (27.3%) squamous cell carcinoma, 5 (7.5%) large cell carcinoma, 4 (6%) bronchoalveolar cell carcinoma, 4 (6%) adenoid cystic carcinoma, 3 (4.6%) malignant carcinoid tumor and 7 (10.6%) had metastasis. The most common symptoms were dyspnea and cough. Histopathologically tumor positive margins were found in 84.8% (A), 10.6% (B), 4.5% (C), and 0% (D). There was a significant statistically difference between tumor involvement at distances 5 mm (A) versus 10-20 mm (B-D) (P <0.001). A 20 mm distance from the gross tumor is considered as a safe surgical margin in any type of malignant pulmonary resections for prevention of local surgical recurrences if there was no pathologic examination before surgery.

  8. Investigation of safe-life fail-safe criteria for the space shuttle

    NASA Technical Reports Server (NTRS)

    1972-01-01

    An investigation was made to determine the effects of a safe-life design approach and a fail-safe design approach on the space shuttle booster vehicle structure, and to recommend any changes to the structural design criteria. Two configurations of the booster vehicle were considered, one incorporating a delta wing (B-9U configuration) and the other a swept wing (B-16B configuration). Several major structural components of the booster were studied to determine the fatigue life, safe-life, and fail-safe capabilities of the baseline design. Each component was investigated to determine the practicability of applying a safe-life or fail-safe design philosophy, the changes such design approaches might require, and the impact of these changes on weight, cost, development plans, and performance.

  9. Sequence specificity, statistical potentials, and three-dimensional structure prediction with self-correcting distance geometry calculations of beta-sheet formation in proteins.

    PubMed Central

    Zhu, H.; Braun, W.

    1999-01-01

    A statistical analysis of a representative data set of 169 known protein structures was used to analyze the specificity of residue interactions between spatial neighboring strands in beta-sheets. Pairwise potentials were derived from the frequency of residue pairs in nearest contact, second nearest and third nearest contacts across neighboring beta-strands compared to the expected frequency of residue pairs in a random model. A pseudo-energy function based on these statistical pairwise potentials recognized native beta-sheets among possible alternative pairings. The native pairing was found within the three lowest energies in 73% of the cases in the training data set and in 63% of beta-sheets in a test data set of 67 proteins, which were not part of the training set. The energy function was also used to detect tripeptides, which occur frequently in beta-sheets of native proteins. The majority of native partners of tripeptides were distributed in a low energy range. Self-correcting distance geometry (SECODG) calculations using distance constraints sets derived from possible low energy pairing of beta-strands uniquely identified the native pairing of the beta-sheet in pancreatic trypsin inhibitor (BPTI). These results will be useful for predicting the structure of proteins from their amino acid sequence as well as for the design of proteins containing beta-sheets. PMID:10048326

  10. Safe Zones: Creating LGBT Safe Space Ally Programs

    ERIC Educational Resources Information Center

    Poynter, Kerry John; Tubbs, Nancy Jean

    2008-01-01

    This article discusses model LGBT Safe Space Ally programs. These programs, often called "Safe Zones," include self selected students, faculty, and employees who publicly show support by displaying stickers, signs, and other identifiable items. Issues covered in the article include history, development, training, membership, assessment, and…

  11. Distance measurement using frequency scanning interferometry with mode-hoped laser

    NASA Astrophysics Data System (ADS)

    Medhat, M.; Sobee, M.; Hussein, H. M.; Terra, O.

    2016-06-01

    In this paper, frequency scanning interferometry is implemented to measure distances up to 5 m absolutely. The setup consists of a Michelson interferometer, an external cavity tunable diode laser, and an ultra-low expansion (ULE) Fabry-Pérot (FP) cavity to measure the frequency scanning range. The distance is measured by acquiring simultaneously the interference fringes from, the Michelson and the FP interferometers, while scanning the laser frequency. An online fringe processing technique is developed to calculate the distance from the fringe ratio while removing the parts result from the laser mode-hops without significantly affecting the measurement accuracy. This fringe processing method enables accurate distance measurements up to 5 m with measurements repeatability ±3.9×10-6 L. An accurate translation stage is used to find the FP cavity free-spectral-range and therefore allow accurate measurement. Finally, the setup is applied for the short distance calibration of a laser distance meter (LDM).

  12. Distance-Dependent Multimodal Image Registration for Agriculture Tasks

    PubMed Central

    Berenstein, Ron; Hočevar, Marko; Godeša, Tone; Edan, Yael; Ben-Shahar, Ohad

    2015-01-01

    Image registration is the process of aligning two or more images of the same scene taken at different times; from different viewpoints; and/or by different sensors. This research focuses on developing a practical method for automatic image registration for agricultural systems that use multimodal sensory systems and operate in natural environments. While not limited to any particular modalities; here we focus on systems with visual and thermal sensory inputs. Our approach is based on pre-calibrating a distance-dependent transformation matrix (DDTM) between the sensors; and representing it in a compact way by regressing the distance-dependent coefficients as distance-dependent functions. The DDTM is measured by calculating a projective transformation matrix for varying distances between the sensors and possible targets. To do so we designed a unique experimental setup including unique Artificial Control Points (ACPs) and their detection algorithms for the two sensors. We demonstrate the utility of our approach using different experiments and evaluation criteria. PMID:26308000

  13. Eye-Safe Lidar System for Pesticide Spray Drift Measurement

    PubMed Central

    Gregorio, Eduard; Rocadenbosch, Francesc; Sanz, Ricardo; Rosell-Polo, Joan R.

    2015-01-01

    Spray drift is one of the main sources of pesticide contamination. For this reason, an accurate understanding of this phenomenon is necessary in order to limit its effects. Nowadays, spray drift is usually studied by using in situ collectors which only allow time-integrated sampling of specific points of the pesticide clouds. Previous research has demonstrated that the light detection and ranging (lidar) technique can be an alternative for spray drift monitoring. This technique enables remote measurement of pesticide clouds with high temporal and distance resolution. Despite these advantages, the fact that no lidar instrument suitable for such an application is presently available has appreciably limited its practical use. This work presents the first eye-safe lidar system specifically designed for the monitoring of pesticide clouds. Parameter design of this system is carried out via signal-to-noise ratio simulations. The instrument is based on a 3-mJ pulse-energy erbium-doped glass laser, an 80-mm diameter telescope, an APD optoelectronic receiver and optomechanically adjustable components. In first test measurements, the lidar system has been able to measure a topographic target located over 2 km away. The instrument has also been used in spray drift studies, demonstrating its capability to monitor the temporal and distance evolution of several pesticide clouds emitted by air-assisted sprayers at distances between 50 and 100 m. PMID:25658395

  14. Correlation Between Cometary Gas/Dust Ratios and Heliocentric Distance

    NASA Astrophysics Data System (ADS)

    Harrington, Olga; Womack, Maria; Lastra, Nathan

    2017-10-01

    We compiled CO-based gas/dust ratios for several comets out to heliocentric distances, rh, of 8 au to probe whether there is a noticeable change in comet behavior over the range that water-ice sublimation starts. Previously, gas/dust ratios were calculated for an ensemble of comets using Q(CO2)/efp values derived from infrared measurements, which showed that the gas/dust ratio follows a rh-2 within 4 AU, but is flat at greater distances (Bauer et al. 2015). Our project focuses on gas/dust ratios for which CO is assumed to be the dominant gas, in order to test whether similar breaks in slope occur for CO. The gas/dust ratios were calculated from measurements of CO production rates (mostly from millimeter-wavelength spectroscopy) and reflected sunlight of comets (mostly via reported visual magnitudes of dusty comets). We present our new CO-based gas/dust ratios at different heliocentric distances, compare them to existing CO2-based gas/dust ratios, and discuss implications for CO-driven and CO2-driven activity. We discuss O.H. acknowledges support from the Hartmann Student Travel Grant program. M.W. acknowledges support from NSF grant AST-1615917.

  15. Safe Schools, Safe Communities.

    ERIC Educational Resources Information Center

    Lewis, Julie E.; Pickett, Dean; Pulliam, Janet L.; Schwartz, Richard A.; St. Germaine, Anne-Marie; Underwood, Julie; Worona, Jay

    Schools must work together with agencies, groups, and individuals to eliminate the forces leading children to violence. Chapter 1, "School Safety: Working Together to Keep Schools Safe," stresses the importance of community collaboration in violence prevention. Effective prevention requires sharing information about students, consistent…

  16. Programmable shunts and headphones: Are they safe together?

    PubMed

    Spader, Heather S; Ratanaprasatporn, Linda; Morrison, John F; Grossberg, Jonathan A; Cosgrove, G Rees

    2015-10-01

    Programmable shunts have a valuable role in the treatment of patients with hydrocephalus, but because a magnet is used to change valve settings, interactions with external magnets may reprogram these shunts. Previous studies have demonstrated the ability of magnetic toys and iPads to erroneously reprogram shunts. Headphones are even more ubiquitous, and they contain an electromagnet for sound projection that sits on the head very close to the shunt valve. This study is the first to look at the magnetic field emissions of headphones and their effect on reprogrammable shunt valves to ascertain whether headphones are safe for patients with these shunts to wear. In this in vitro study of the magnetic properties of headphones and their interactions with 3 different programmable shunts, the authors evaluated Apple earbuds, Beats by Dr. Dre, and Bose QuietComfort Acoustic Noise Cancelling headphones. Each headphone was tested for electromagnetic field emissions using a direct current gaussmeter. The following valves were evaluated: Codman Hakim programmable valve, Medtronic Strata II valve, and Aesculap proGAV. Each valve was tested at distances of 0 to 50 mm (in 5-mm increments) from each headphone. The exposure time at each distance was 1 minute, and 3 trials were performed to confirm results at each valve setting and distance. All 3 headphones generated magnetic fields greater than the respective shunt manufacturer's recommended strength of exposure, but these fields did not persist beyond 5 mm. By 2 cm, the fields levels were below 20 G, well below the Medtronic recommendation of 90 G and the Codman recommendation of 80 G. Because the mechanism for the proGAV is different, there is no recommended gauss level. There was no change in gauss-level emissions by the headphones with changes in frequency and amplitude. Both the Strata and Codman-Hakim valves were reprogrammed by direct contact (distance 0 mm) with the Bose headphones. When a rotation component was added, all

  17. High Performance Automatic Character Skinning Based on Projection Distance

    NASA Astrophysics Data System (ADS)

    Li, Jun; Lin, Feng; Liu, Xiuling; Wang, Hongrui

    2018-03-01

    Skeleton-driven-deformation methods have been commonly used in the character deformations. The process of painting skin weights for character deformation is a long-winded task requiring manual tweaking. We present a novel method to calculate skinning weights automatically from 3D human geometric model and corresponding skeleton. The method first, groups each mesh vertex of 3D human model to a skeleton bone by the minimum distance from a mesh vertex to each bone. Secondly, calculates each vertex's weights to the adjacent bones by the vertex's projection point distance to the bone joints. Our method's output can not only be applied to any kind of skeleton-driven deformation, but also to motion capture driven (mocap-driven) deformation. Experiments results show that our method not only has strong generality and robustness, but also has high performance.

  18. STScI-PRC96-21b DISTANCE MEASUREMENTS TO A TYPE-IA SUPERNOVA BEARING GALAXY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This Hubble Space Telescope image shows NGC 4639, a spiral galaxy located 78 million light-years away in the Virgo cluster of galaxies. The blue dots in the galaxy's outlying regions indicate the presence of young stars. Among them are young, bright stars called Cepheids, which are used as reliable milepost markers to obtain accurate distances to nearby galaxies. Astronomers measure the brightness of Cepheids to calculate the distance to a galaxy. Allan Sandage's team used Cepheids to measure the distance to NGC 4639, the farthest galaxy to which Cepheid distance has been calculated. After using Cepheids to calculate the distance to NGC 4639, the team compared the results to the peak brightness measurements of SN 1990N, a type Ia supernova located in the galaxy. Then they compared those numbers with the peak brightness of supernovae similarly calibrated in nearby galaxies. The team then determined that type Ia supernovae are reliable secondary distance markers, and can be used to determine distances to galaxies several hundred times farther away than Cepheids. An accurate value for the Hubble Constant depends on Cepheids and secondary distance methods. The color image was made from separate exposures taken in the visible and near-infrared regions of the spectrum with the Wide Field Planetary Camera 2. Credit: A. Sandage (Carnegie Observatories), A. Saha (Space Telescope Science Institute), G.A. Tammann, and L. Labhardt (Astronomical Institute, University Basel), F.D. Macchetto and N. Panagia (Space Telescope Science Institute/ European Space Agency), and NASA Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo.

  19. Anaerobic work calculated in cycling time trials of different length.

    PubMed

    Mulder, Roy C; Noordhof, Dionne A; Malterer, Katherine R; Foster, Carl; de Koning, Jos J

    2015-03-01

    Previous research showed that gross efficiency (GE) declines during exercise and therefore influences the expenditure of anaerobic and aerobic resources. To calculate the anaerobic work produced during cycling time trials of different length, with and without a GE correction. Anaerobic work was calculated in 18 trained competitive cyclists during 4 time trials (500, 1000, 2000, and 4000-m). Two additional time trials (1000 and 4000 m) that were stopped at 50% of the corresponding "full" time trial were performed to study the rate of the decline in GE. Correcting for a declining GE during time-trial exercise resulted in a significant (P<.001) increase in anaerobically attributable work of 30%, with a 95% confidence interval of [25%, 36%]. A significant interaction effect between calculation method (constant GE, declining GE) and distance (500, 1000, 2000, 4000 m) was found (P<.001). Further analysis revealed that the constant-GE calculation method was different from the declining method for all distances and that anaerobic work calculated assuming a constant GE did not result in equal values for anaerobic work calculated over different time-trial distances (P<.001). However, correcting for a declining GE resulted in a constant value for anaerobically attributable work (P=.18). Anaerobic work calculated during short time trials (<4000 m) with a correction for a declining GE is increased by 30% [25%, 36%] and may represent anaerobic energy contributions during high-intensity exercise better than calculating anaerobic work assuming a constant GE.

  20. An improved approach to the analysis of drug-protein binding by distance geometry

    NASA Technical Reports Server (NTRS)

    Goldblum, A.; Kieber-Emmons, T.; Rein, R.

    1986-01-01

    The calculation of side chain centers of coordinates and the subsequent generation of side chain-side chain and side chain-backbone distance matrices is suggested as an improved method for viewing interactions inside proteins and for the comparison of protein structures. The use of side chain distance matrices is demonstrated with free PTI, and the use of difference distance matrices for side chains is shown for free and trypsin-bound PTI as well as for the X-ray structures of trypsin complexes with PTI and with benzamidine. It is found that conformational variations are reflected in the side chain distance matrices much more than in the standard C-C distance representations.

  1. The Araucaria project. The distance to the small Magellanic Cloud from late-type eclipsing binaries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graczyk, Dariusz; Pietrzyński, Grzegorz; Gieren, Wolfgang

    2014-01-01

    We present a distance determination to the Small Magellanic Cloud (SMC) based on an analysis of four detached, long-period, late-type eclipsing binaries discovered by the Optical Gravitational Lensing Experiment (OGLE) survey. The components of the binaries show negligible intrinsic variability. A consistent set of stellar parameters was derived with low statistical and systematic uncertainty. The absolute dimensions of the stars are calculated with a precision of better than 3%. The surface brightness-infrared color relation was used to derive the distance to each binary. The four systems clump around a distance modulus of (m – M) = 18.99 with a dispersionmore » of only 0.05 mag. Combining these results with the distance published by Graczyk et al. for the eclipsing binary OGLE SMC113.3 4007, we obtain a mean distance modulus to the SMC of 18.965 ± 0.025 (stat.) ± 0.048 (syst.) mag. This corresponds to a distance of 62.1 ± 1.9 kpc, where the error includes both uncertainties. Taking into account other recent published determinations of the SMC distance we calculated the distance modulus difference between the SMC and the Large Magellanic Cloud equal to 0.458 ± 0.068 mag. Finally, we advocate μ{sub SMC} = 18.95 ± 0.07 as a new 'canonical' value of the distance modulus to this galaxy.« less

  2. Image integration into 3-dimensional-electro-anatomical mapping system facilitates safe ablation of ventricular arrhythmias originating from the aortic root and its vicinity.

    PubMed

    Jularic, Mario; Akbulak, Ruken Özge; Schäffer, Benjamin; Moser, Julia; Nuehrich, Jana; Meyer, Christian; Eickholt, Christian; Willems, Stephan; Hoffmann, Boris A

    2018-03-01

    During ablation in the vicinity of the coronary arteries establishing a safe distance from the catheter tip to the relevant vessels is mandatory and usually assessed by fluoroscopy alone. The aim of the study was to investigate the feasibility of an image integration module (IIM) for continuous monitoring of the distance of the ablation catheter tip to the main coronary arteries during ablation of ventricular arrhythmias (VA) originating in the sinus of valsalva (SOV) and the left ventricular summit part of which can be reached via the great cardiac vein (GCV). Of 129 patients undergoing mapping for outflow tract arrhythmias from June 2014 till October 2015, a total of 39 patients (52.4 ± 18.1 years, 17 female) had a source of origin in the SOV or the left ventricular summit. Radiofrequency (RF) ablation was performed when a distance of at least 5 mm could be demonstrated with IIM. A safe distance in at least one angiographic plane could be demonstrated in all patients with a source of origin in the SOV, whereas this was not possible in 50% of patients with earliest activation in the summit area. However, using the IIM a safe position at an adjacent site within the GCV could be obtained in three of these cases and successful RF ablation performed safely without any complications. Ablation was successful in 100% of patients with an origin in the SOV, whereas VAs originating from the left ventricular summit could be abolished completely in only 60% of cases. Image integration combining electroanatomical mapping and fluoroscopy allows assessment of the safety of a potential ablation site by continuous real-time monitoring of the spatial relations of the catheter tip to the coronary vessels prior to RF application. It aids ablation in anatomically complex regions like the SOV or the ventricular summit providing biplane angiograms merged into the three-dimensional electroanatomical map. Published on behalf of the European Society of Cardiology. All rights reserved.

  3. Estimating plant distance in maize using Unmanned Aerial Vehicle (UAV).

    PubMed

    Zhang, Jinshui; Basso, Bruno; Price, Richard F; Putman, Gregory; Shuai, Guanyuan

    2018-01-01

    Distance between rows and plants are essential parameters that affect the final grain yield in row crops. This paper presents the results of research intended to develop a novel method to quantify the distance between maize plants at field scale using an Unmanned Aerial Vehicle (UAV). Using this method, we can recognize maize plants as objects and calculate the distance between plants. We initially developed our method by training an algorithm in an indoor facility with plastic corn plants. Then, the method was scaled up and tested in a farmer's field with maize plant spacing that exhibited natural variation. The results of this study demonstrate that it is possible to precisely quantify the distance between maize plants. We found that accuracy of the measurement of the distance between maize plants depended on the height above ground level at which UAV imagery was taken. This study provides an innovative approach to quantify plant-to-plant variability and, thereby final crop yield estimates.

  4. Heterogeneity Measurement Based on Distance Measure for Polarimetric SAR Data

    NASA Astrophysics Data System (ADS)

    Xing, Xiaoli; Chen, Qihao; Liu, Xiuguo

    2018-04-01

    To effectively test the scene heterogeneity for polarimetric synthetic aperture radar (PolSAR) data, in this paper, the distance measure is introduced by utilizing the similarity between the sample and pixels. Moreover, given the influence of the distribution and modeling texture, the K distance measure is deduced according to the Wishart distance measure. Specifically, the average of the pixels in the local window replaces the class center coherency or covariance matrix. The Wishart and K distance measure are calculated between the average matrix and the pixels. Then, the ratio of the standard deviation to the mean is established for the Wishart and K distance measure, and the two features are defined and applied to reflect the complexity of the scene. The proposed heterogeneity measure is proceeded by integrating the two features using the Pauli basis. The experiments conducted on the single-look and multilook PolSAR data demonstrate the effectiveness of the proposed method for the detection of the scene heterogeneity.

  5. Nonlinear differential equations for the wavefront surface at arbitrary Hartmann-plane distances.

    PubMed

    Téllez-Quiñones, Alejandro; Malacara-Doblado, Daniel; Flores-Hernández, Ricardo; Gutiérrez-Hernández, David A; León-Rodríguez, Miguel

    2016-03-20

    In the Hartmann test, a wave aberration function W is estimated from the information of the spot diagram drawn in an observation plane. The distance from a reference plane to the observation plane, the Hartmann-plane distance, is typically chosen as z=f, where f is the radius of a reference sphere. The function W and the transversal aberrations {X,Y} calculated at the plane z=f are related by two well-known linear differential equations. Here, we propose two nonlinear differential equations to denote a more general relation between W and the transversal aberrations {U,V} calculated at any arbitrary Hartmann-plane distance z=r. We also show how to directly estimate the wavefront surface w from the information of {U,V}. The use of arbitrary r values could improve the reliability of the measurements of W, or w, when finding difficulties in adequate ray identification at z=f.

  6. Psychological Distance between Categories in the Likert Scale: Comparing Different Numbers of Options

    ERIC Educational Resources Information Center

    Wakita, Takafumi; Ueshima, Natsumi; Noguchi, Hiroyuki

    2012-01-01

    This study examined whether the number of options in the Likert scale influences the psychological distance between categories. The most important assumption when using the Likert scale is that the psychological distance between options is equal. The authors proposed a new algorithm for calculating the scale values of options by applying item…

  7. Celebrating Distance Teaching Innovations: The Certificate in Distance Teaching.

    ERIC Educational Resources Information Center

    Boylan, Colin; Tuovinen, Juhani

    Charles Sturt University (Riverina, Australia) has initiated the Certificate in Distance Teaching course for rural teachers working in a distance education setting to extend their understandings about rural and distance education topics. Two semester-long subjects constitute the course: pedagogy of distance teaching and organization of distance…

  8. Distance Training as Part of a Distance Consulting Solution.

    ERIC Educational Resources Information Center

    Fulantelli, Giovanni; Chiazzese, Giuseppe; Allegra, Mario

    "Distance Training" models, when integrated in a more complex framework, such as a "Distance Consulting" model, present specific features and impose a revision of the strategies commonly adopted in distance training experiences. This paper reports on the distance training strategies adopted in a European funded project aimed at…

  9. Application of Multifunctional Doppler LIDAR for Noncontact Track Speed, Distance, and Curvature Assessment

    NASA Astrophysics Data System (ADS)

    Munoz, Joshua

    The primary focus of this research is evaluation of feasibility, applicability, and accuracy of Doppler Light Detection And Ranging (LIDAR) sensors as non-contact means for measuring track speed, distance traveled, and curvature. Speed histories, currently measured with a rotary, wheelmounted encoder, serve a number of useful purposes, one significant use involving derailment investigations. Distance calculation provides a spatial reference system for operators to locate track sections of interest. Railroad curves, using an IMU to measure curvature, are monitored to maintain track infrastructure within regulations. Speed measured with high accuracy leads to highfidelity distance and curvature data through utilization of processor clock rate and left-and rightrail speed differentials during curve navigation, respectively. Wheel-mounted encoders, or tachometers, provide a relatively low-resolution speed profile, exhibit increased noise with increasing speed, and are subject to the inertial behavior of the rail car which affects output data. The IMU used to measure curvature is dependent on acceleration and yaw rate sensitivity and experiences difficulty in low-speed conditions. Preliminary system tests onboard a "Hy-Rail" utility vehicle capable of traveling on rail show speed capture is possible using the rails as the reference moving target and furthermore, obtaining speed profiles from both rails allows for the calculation of speed differentials in curves to estimate degrees curvature. Ground truth distance calibration and curve measurement were also carried out. Distance calibration involved placement of spatial landmarks detected by a sensor to synchronize distance measurements as a pre-processing procedure. Curvature ground truth measurements provided a reference system to confirm measurement results and observe alignment variation throughout a curve. Primary testing occurred onboard a track geometry rail car, measuring rail speed over substantial mileage in

  10. Manifold learning-based subspace distance for machinery damage assessment

    NASA Astrophysics Data System (ADS)

    Sun, Chuang; Zhang, Zhousuo; He, Zhengjia; Shen, Zhongjie; Chen, Binqiang

    2016-03-01

    Damage assessment is very meaningful to keep safety and reliability of machinery components, and vibration analysis is an effective way to carry out the damage assessment. In this paper, a damage index is designed by performing manifold distance analysis on vibration signal. To calculate the index, vibration signal is collected firstly, and feature extraction is carried out to obtain statistical features that can capture signal characteristics comprehensively. Then, manifold learning algorithm is utilized to decompose feature matrix to be a subspace, that is, manifold subspace. The manifold learning algorithm seeks to keep local relationship of the feature matrix, which is more meaningful for damage assessment. Finally, Grassmann distance between manifold subspaces is defined as a damage index. The Grassmann distance reflecting manifold structure is a suitable metric to measure distance between subspaces in the manifold. The defined damage index is applied to damage assessment of a rotor and the bearing, and the result validates its effectiveness for damage assessment of machinery component.

  11. Safe sex self-efficacy and safe sex practice in a Southern United States College

    PubMed Central

    Addoh, Ovuokerie; Sng, Eveleen; Loprinzi, Paul D.

    2017-01-01

    Background: The purpose of this study was to assess the association between safe sex self-efficacy and safe-sex practice in a Southern college setting. Methods: Multivariable logistic regression models were used to examine the association between safe sex self-efficacy in four domains (mechanics, partner disapproval, assertiveness, intoxicants) and safe sex practice (outcome variable). Results: For every 1-unit increase in the composite condom use self-efficacy score, there was an 8% increase in the odds of being beyond the median safe-sex practice score (odds ration [OR]: 1.08, 95% CI: 1.02-1.15). Additionally, for every 1-unit increase in intoxicants self-efficacy score, there was a 31% increase in the odds of being beyond the median safe-sex practice score (OR: 1.31, 95% CI: 1.08-1.58). Conclusion: A greater degree of safe-sex self-efficacy is associated with increased odds of safe-sex practice. These findings are informative for the development of targeted approaches to foster safe-sex behavior in Southern US colleges. PMID:28326287

  12. [A Study of the Relationship Among Genetic Distances, NIR Spectra Distances, and NIR-Based Identification Model Performance of the Seeds of Maize Iinbred Lines].

    PubMed

    Liu, Xu; Jia, Shi-qiang; Wang, Chun-ying; Liu, Zhe; Gu, Jian-cheng; Zhai, Wei; Li, Shao-ming; Zhang, Xiao-dong; Zhu, De-hai; Huang, Hua-jun; An, Dong

    2015-09-01

    This paper explored the relationship among genetic distances, NIR spectra distances and NIR-based identification model performance of the seeds of maize inbred lines. Using 3 groups (total 15 pairs) of maize inbred lines whose genetic distaches are different as experimental materials, we calculates the genetic distance between these seeds with SSR markers and uses Euclidean distance between distributed center points of maize NIR spectrum in the PCA space as the distances of NIR spectrum. BPR method is used to build identification model of inbred lines and the identification accuracy is used as a measure of model identification performance. The results showed that, the correlation of genetic distance and spectra distancesis 0.9868, and it has a correlation of 0.9110 with the identification accuracy, which is highly correlated. This means near-Infrared spectrum of seedscan reflect genetic relationship of maize inbred lines. The smaller the genetic distance, the smaller the distance of spectrum, the poorer ability of model to identify. In practical application, near infrared spectrum analysis technology has the potential to be used to analyze maize inbred genetic relations, contributing much to genetic breeding, identification of species, purity sorting and so on. What's more, when creating a NIR-based identification model, the impact of the maize inbred lines which have closer genetic relationship should be fully considered.

  13. Dependency distance minimization in understanding of ambiguous structure. Comment on "Dependency distance: A new perspective on syntactic patterns in natural languages" by Haitao Liu et al.

    NASA Astrophysics Data System (ADS)

    Zhao, Yiyi

    2017-07-01

    Dependency Distance, proposed by Hudson [1], calculated by Liu [2,3], is an important concept in Dependency Theory. It can be used as a measure of the syntactic difficulty, and lots of research [2,4] have testified the universal of Dependency Distance in various languages. Human languages seem to present a preference for short dependency distance, which may be explained in terms of general cognitive constraint of limited working memory [5]. Psychological experiments in English, German, Russian and Chinese support the hypothesis that Dependency Distance minimization (DDM) make languages to evolve into some syntactic patterns to reduce memory burden [6-9]. The study of psychology focuses on the process and mechanism of syntactic structure selection in speech comprehension. In many speech comprehension experiments [10], ambiguous structure is an important experimental material.

  14. DroidSafe

    DTIC Science & Technology

    2016-12-01

    branches of our work . 3.1 Understanding Sensitive API Call and API Information Usage Android applications are written in a type- safe language (Java...directly invoke resolved targets. Because DroidSafe works with a comprehensive model of the Android environment , it supports precise resolution of...STATEMENT. FOR THE CHIEF ENGINEER: / S / / S / MARK K. WILLIAMS WARREN H. DEBANY, JR. Work Unit Manager

  15. A Safe Ride to School; A Safe Ride Home.

    ERIC Educational Resources Information Center

    Illinois State Board of Education, Springfield.

    Text and illustrations are used to teach safe school bus riding practices. The guide begins with instructions to parents or guardians to set a good example of safe behavior, and to help children learn safety rules and be on time. Instructions to children concern obeying the bus driver, boarding the bus, riding the bus, crossing the road, and using…

  16. The effect of inhomogeneities on the distance to the last scattering surface and the accuracy of the CMB analysis

    NASA Astrophysics Data System (ADS)

    Bolejko, Krzysztof

    2011-02-01

    The standard analysis of the CMB data assumes that the distance to the last scattering surface can be calculated using the distance-redshift relation as in the Friedmann model. However, in the inhomogeneous universe, even if langδρrang = 0, the distance relation is not the same as in the unperturbed universe. This can be of serious consequences as a change of distance affects the mapping of CMB temperature fluctuations into the angular power spectrum Cl. In addition, if the change of distance is relatively uniform no new temperature fluctuations are generated. It is therefore a different effect than the lensing or ISW effects which introduce additional CMB anisotropies. This paper shows that the accuracy of the CMB analysis can be impaired by the accuracy of calculation of the distance within the cosmological models. Since this effect has not been fully explored before, to test how the inhomogeneities affect the distance-redshift relation, several methods are examined: the Dyer-Roeder relation, lensing approximation, and non-linear Swiss-Cheese model. In all cases, the distance to the last scattering surface is different than when homogeneity is assumed. The difference can be as low as 1% and as high as 80%. An usual change of the distance is around 20-30%. Since the distance to the last scattering surface is set by the position of the CMB peaks, in order to have a good fit, the distance needs to be adjusted. After correcting the distance, the cosmological parameters change. Therefore, a not properly estimated distance to the last scattering surface can be a major source of systematics. This paper shows that if inhomogeneities are taken into account when calculating the distance then models with positive spatial curvature and with ΩΛ ~ 0.8-0.9 are preferred.

  17. Optimizing distance-based methods for large data sets

    NASA Astrophysics Data System (ADS)

    Scholl, Tobias; Brenner, Thomas

    2015-10-01

    Distance-based methods for measuring spatial concentration of industries have received an increasing popularity in the spatial econometrics community. However, a limiting factor for using these methods is their computational complexity since both their memory requirements and running times are in {{O}}(n^2). In this paper, we present an algorithm with constant memory requirements and shorter running time, enabling distance-based methods to deal with large data sets. We discuss three recent distance-based methods in spatial econometrics: the D&O-Index by Duranton and Overman (Rev Econ Stud 72(4):1077-1106, 2005), the M-function by Marcon and Puech (J Econ Geogr 10(5):745-762, 2010) and the Cluster-Index by Scholl and Brenner (Reg Stud (ahead-of-print):1-15, 2014). Finally, we present an alternative calculation for the latter index that allows the use of data sets with millions of firms.

  18. [Onyx embolization for treatment of dural arteriovenous fistula: comparison of long- distance versus routine injection method].

    PubMed

    He, Xiao-Yan; Zhang, Guo-Zhong; Li, Ming-Zhou; Wang, Gang; Liu, Dan; Qi, Song-Tao; Li, Wei-Guang; Feng, Wen-Feng

    2016-03-01

    To compare the efficacy, clinical characteristics, safety, injection time and radiation exposure of Onyx embolization using a long-distance injection method and routine injection method for management of dural arteriovenous fistula (DAVF). The clinical data were retrospectively analyzed in 59 patients with DAVF treated with Onyx embolization using long-distance injection method (28 patients) and routine injection method (31 patients). The efficacy, safety, injection time and radiation exposure during Onyx embolization were compared between the two injections methods. The average radiation dose exposure to the surgeon per procedure was significantly lower in the long-distance injection group than in the routine group. The injection time (P=0.53), injection volume (P=0.78), number of supply arteries (P=0.80), Cognard types (P=0.67), and effect of embolization (P=0.88) were all similar between the two groups. Endovaseular treatment of intracranial DAVF with Onyx embolization using the long-distance injection method is feasible, safe and effective and can reduce the radiation exposure to the surgeon.

  19. Time Variation of the Distance Separating Bomb and Dive Bomber Subsequent to Bomb Release

    NASA Technical Reports Server (NTRS)

    Mathews, Charles W.

    1952-01-01

    A study has been made of the variation of the distance separating bomb and aircraft with time after release as applied to dive-bombing operations, Separation distances determined from this study are presented in terms of two variables only, dive angle and maximum airplane accelerometer reading; the values of separation distance include the effects of delay in initiation of the pull-out and lag in attainment of the maximum normal acceleration.Contains analysis and calculations of the separation distances between bomb and dive bomber following bomb release, Separation distances as determined by the dive angle and the maximum airplane accelerometer reading are presented in a single chart.

  20. Increasing distance from California bay laurel reduces the risk and severity of Phytophthora ramorum canker in coast live oak

    Treesearch

    Tedmund J. Swiecki; Elizabeth A. Bernhardt

    2008-01-01

    Foliar infections in California bay (Umbellularia californica) are the most important known source of inoculum contributing to Phytophthora ramorum canker in coast live oak (Quercus agrifolia). This research addressed the question whether there is a ?safe? distance between California bay and coast live oak beyond...

  1. The extraction of drug-disease correlations based on module distance in incomplete human interactome.

    PubMed

    Yu, Liang; Wang, Bingbo; Ma, Xiaoke; Gao, Lin

    2016-12-23

    Extracting drug-disease correlations is crucial in unveiling disease mechanisms, as well as discovering new indications of available drugs, or drug repositioning. Both the interactome and the knowledge of disease-associated and drug-associated genes remain incomplete. We present a new method to predict the associations between drugs and diseases. Our method is based on a module distance, which is originally proposed to calculate distances between modules in incomplete human interactome. We first map all the disease genes and drug genes to a combined protein interaction network. Then based on the module distance, we calculate the distances between drug gene sets and disease gene sets, and take the distances as the relationships of drug-disease pairs. We also filter possible false positive drug-disease correlations by p-value. Finally, we validate the top-100 drug-disease associations related to six drugs in the predicted results. The overlapping between our predicted correlations with those reported in Comparative Toxicogenomics Database (CTD) and literatures, and their enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways demonstrate our approach can not only effectively identify new drug indications, but also provide new insight into drug-disease discovery.

  2. Use Medicines Safely

    MedlinePlus

    ... Medicines Safely Print This Topic En español Use Medicines Safely Browse Sections The Basics Overview Prescription Medicines ... Medicines 1 of 7 sections The Basics: Prescription Medicines There are different types of medicine. The 2 ...

  3. Picture Me Safe

    ERIC Educational Resources Information Center

    Irvin, Daniel W.

    1977-01-01

    The validity of well-written articles can be destroyed by poor illustration, especially when the pictures show unsafe practices. The responsibility lies with the author to provide clear printable pictures showing safe working environments and safe practices. (Editor)

  4. Safe use of cellular telephones in hospitals: fundamental principles and case studies.

    PubMed

    Cohen, Ted; Ellis, Willard S; Morrissey, Joseph J; Bakuzonis, Craig; David, Yadin; Paperman, W David

    2005-01-01

    Many industries and individuals have embraced cellular telephones. They provide mobile, synchronous communication, which could hypothetically increase the efficiency and safety of inpatient healthcare. However, reports of early analog cellular telephones interfering with critical life-support machines had led many hospitals to strictly prohibit cellular telephones. A literature search revealed that individual hospitals now are allowing cellular telephone use with various policies to prevent electromagnetic interference with medical devices. The fundamental principles underlying electromagnetic interference are immunity, frequency, modulation technology, distance, and power Electromagnetic interference risk mitigation methods based on these principles have been successfully implemented. In one case study, a minimum distance between cellular telephones and medical devices is maintained, with restrictions in critical areas. In another case study, cellular telephone coverage is augmented to automatically control the power of the cellular telephone. While no uniform safety standard yet exists, cellular telephones can be safely used in hospitals when their use is managed carefully.

  5. Keeping you at arm's length: modifying peripersonal space influences interpersonal distance.

    PubMed

    Quesque, F; Ruggiero, G; Mouta, S; Santos, J; Iachini, T; Coello, Y

    2017-07-01

    Peripersonal space represents the area around the body where objects are coded in motor terms for the purpose of voluntary goal-directed actions. Previous studies have suggested that peripersonal space is also a safe space linked with our private area, influencing interpersonal space in social contexts. However, whether these two spaces rely on similar embodied processes remains an open issue. In the present study, participants observed a point-light walker (PLW) approaching them from different directions and passing near them at different distances from their right or left shoulder. While approaching, the PLW disappeared at a distance of 2 m and the task for the participants was to estimate if the interpersonal distance, at the time the PLW would have reached their level, was comfortable or not. Between two sessions of comfort judgments, the participants manipulated a 70 cm tool entailing an extension of peripersonal space, or a 10 cm tool entailing no extension of peripersonal space. The results revealed that the comfortable interpersonal distance was larger when the PLW crossed the mid-sagittal plane of the participants than when it approached them laterally, with a concomitant increase of response time. After participants manipulated the long tool, comfortable interpersonal distance increased, but predominantly when the PLW trajectory implied crossing the participants' mid-sagittal plane. This effect was not observed when participants manipulated the short tool. Two control tasks showed that using the long tool modified the reachability (control 1), but not the time to passage (control 2) estimates of PLW stimuli, suggesting that tool use extended peripersonal space without changing perceived visual distances. Overall, the data show that comfortable interpersonal distance is linked to the representation of peripersonal space. As a consequence, increasing peripersonal space through tool use has the immediate consequence that comfortable interpersonal distance

  6. Spatial generalised linear mixed models based on distances.

    PubMed

    Melo, Oscar O; Mateu, Jorge; Melo, Carlos E

    2016-10-01

    Risk models derived from environmental data have been widely shown to be effective in delineating geographical areas of risk because they are intuitively easy to understand. We present a new method based on distances, which allows the modelling of continuous and non-continuous random variables through distance-based spatial generalised linear mixed models. The parameters are estimated using Markov chain Monte Carlo maximum likelihood, which is a feasible and a useful technique. The proposed method depends on a detrending step built from continuous or categorical explanatory variables, or a mixture among them, by using an appropriate Euclidean distance. The method is illustrated through the analysis of the variation in the prevalence of Loa loa among a sample of village residents in Cameroon, where the explanatory variables included elevation, together with maximum normalised-difference vegetation index and the standard deviation of normalised-difference vegetation index calculated from repeated satellite scans over time. © The Author(s) 2013.

  7. Effect of Geographic Distance on Distance Education: An Empirical Study

    ERIC Educational Resources Information Center

    Luo, Heng; Robinson, Anthony C.; Detwiler, Jim

    2014-01-01

    This study investigates the effect of geographic distance on students' distance learning experience with the aim to provide tentative answers to a fundamental question--does geographic distance matter in distance education? Using educational outcome data collected from an online master's program in Geographic Information Systems, this study…

  8. Safe Schools/Safe Communities: A Directory of Resources for Pennsylvania.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg.

    This document contains a directory of resources available in Pennsylvania to help achieve the goal of safe schools. Following a copy of the Safe Schools Act of 1993, nine sections list agencies that provide services and products under the headings of: conflict resolution/mediation, gangs, suicide, crisis response, family violence, diversity,…

  9. Lessons Learned from Safe Kids/Safe Streets. Juvenile Justice Bulletin

    ERIC Educational Resources Information Center

    Cronin, Roberta; Gragg, Frances; Schultz, Dana; Eisen, Karla

    2006-01-01

    This bulletin reports results from an evaluation of six sites of the Safe Kids/Safe Streets (SK/SS) program, which applies a comprehensive, collaborative approach to the child maltreatment field. The bulletin provides insights into collaboration building, systems reform, service options, and other strategies. Among the findings were that the SK/SS…

  10. Distance Learning.

    ERIC Educational Resources Information Center

    Orey, Michael; Koenecke, Lynne; Snider, Richard C.; Perkins, Ross A.; Holmes, Glen A.; Lockee, Barbara B.; Moller, Leslie A.; Harvey, Douglas; Downs, Margaret; Godshalk, Veronica M.

    2003-01-01

    Contains four articles covering trends and issues on distance learning including: the experience of two learners learning via the Internet; a systematic approach to determining the scalability of a distance education program; identifying factors that affect learning community development and performance in asynchronous distance education; and…

  11. Structure of aqueous cesium metaborate solutions by X-ray scattering and DFT calculation

    NASA Astrophysics Data System (ADS)

    Zhang, W. Q.; Fang, C. H.; Fang, Y.; Zhu, F. Y.; Zhou, Y. Q.; Liu, H. Y.; Li, W.

    2018-05-01

    In the present work, precise radial distribution function (RDF) of cesium metaborate solutions with salt-water molar ratio of 1:25, 1:30 and 1:35 in large scattering vector range (3.91-214.26 nm-1) were obtained by X-ray scattering. Polyborate species were given using Newton iteration method with measured pH and literature equilibrium constants. In model calculation, structural parameters such as the coordination number, interatomic distance and Debye-Waller factor were given through model calculation. The B-O(H2O) distance was determined to be ∼0.37 nm with the hydration number of ∼7.8 for B(OH)4-. The Cs-B distance of the contact ions CsB(OH)40 was measured to be ∼0.46 nm with interaction number of ∼0.77. The interaction distances and coordination number for the first shell and the second shell of Cs-O(W) are ∼0.325 nm, ∼0.517 nm and ∼8.0, ∼11, respectively. Five low-energy configurations of [Cs(H2O)8]+ were given with DFT calculation, including the first and the second hydration shell, and the most stable eight-coordinated one is close to the model calculation. Furthermore, the effect of concentration is discussed in the X-ray scattering analysis part, showing that hydration degree changes with the concentration. For the coordination number and distance of Cs-O(H2O) and H-bonding decrease with the increasing concentration. The coordination number of Cs-O(H2O) keep stable, and the coordination distance changes from 3.25 nm to 3.30 nm. For H-bonding, which the coordination number varies from 2.20 to 2.24, and the coordination distance varies from 2.76 nm to 2.78 nm with the decreasing concentration.

  12. Distance Education.

    ERIC Educational Resources Information Center

    ASPBAE Courier, 1984

    1984-01-01

    This publication is devoted to distance education. "The Future of Distance Teaching Universities in a Worldwide Perspectives" (John S. Daniel) examines challenges likely to face the various countries and regions of the world in the next decade. "An Australian University's Approach to Distance Education--Formal and Non-Formal"…

  13. 76 FR 12719 - Safe Schools/Healthy Students Program; Office of Safe and Drug-Free Schools; Safe Schools/Healthy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-08

    ... official version of this document is the document published in the Federal Register. Free Internet access... DEPARTMENT OF EDUCATION Safe Schools/Healthy Students Program; Office of Safe and Drug- Free... telecommunications device for the deaf (TDD), call the Federal Relay Service (FRS), toll free, at 1-800-877-8339...

  14. Safe syringe disposal is related to safe syringe access among HIV-positive injection drug users.

    PubMed

    Coffin, Phillip O; Latka, Mary H; Latkin, Carl; Wu, Yingfeng; Purcell, David W; Metsch, Lisa; Gomez, Cynthia; Gourevitch, Marc N

    2007-09-01

    We evaluated the effect of syringe acquisition on syringe disposal among HIV-positive injection drug users (IDUs) in Baltimore, New York City, and San Francisco (N = 680; mean age 42 years, 62% male, 59% African-American, 21% Hispanic, 12% White). Independent predictors of safe disposal were acquiring syringes through a safe source and ever visiting a syringe exchange program. Weaker predictors included living in San Francisco, living in the area longer, less frequent binge drinking, injecting with an HIV+ partner, peer norms supporting safe injection, and self-empowerment. Independent predictors of safe "handling"-both acquiring and disposing of syringes safely-also included being from New York and being older. HIV-positive IDUs who obtain syringes from a safe source are more likely to safely dispose; peer norms contribute to both acquisition and disposal. Interventions to improve disposal should include expanding sites of safe syringe acquisition while enhancing disposal messages, alternatives, and convenience.

  15. Dose Calculation For Accidental Release Of Radioactive Cloud Passing Over Jeddah

    NASA Astrophysics Data System (ADS)

    Alharbi, N. D.; Mayhoub, A. B.

    2011-12-01

    For the evaluation of doses after the reactor accident, in particular for the inhalation dose, a thorough knowledge of the concentration of the various radionuclide in air during the passage of the plume is required. In this paper we present an application of the Gaussian Plume Model (GPM) to calculate the atmospheric dispersion and airborne radionuclide concentration resulting from radioactive cloud over the city of Jeddah (KSA). The radioactive cloud is assumed to be emitted from a reactor of 10 MW power in postulated accidental release. Committed effective doses (CEDs) to the public at different distance from the source to the receptor are calculated. The calculations were based on meteorological condition and data of the Jeddah site. These data are: pasquill atmospheric stability is the class B and the wind speed is 2.4m/s at 10m height in the N direction. The residence time of some radionuclides considered in this study were calculated. The results indicate that, the values of doses first increase with distance, reach a maximum value and then gradually decrease. The total dose received by human is estimated by using the estimated values of residence time of each radioactive pollutant at different distances.

  16. Supertrees Based on the Subtree Prune-and-Regraft Distance

    PubMed Central

    Whidden, Christopher; Zeh, Norbert; Beiko, Robert G.

    2014-01-01

    Supertree methods reconcile a set of phylogenetic trees into a single structure that is often interpreted as a branching history of species. A key challenge is combining conflicting evolutionary histories that are due to artifacts of phylogenetic reconstruction and phenomena such as lateral gene transfer (LGT). Many supertree approaches use optimality criteria that do not reflect underlying processes, have known biases, and may be unduly influenced by LGT. We present the first method to construct supertrees by using the subtree prune-and-regraft (SPR) distance as an optimality criterion. Although calculating the rooted SPR distance between a pair of trees is NP-hard, our new maximum agreement forest-based methods can reconcile trees with hundreds of taxa and > 50 transfers in fractions of a second, which enables repeated calculations during the course of an iterative search. Our approach can accommodate trees in which uncertain relationships have been collapsed to multifurcating nodes. Using a series of benchmark datasets simulated under plausible rates of LGT, we show that SPR supertrees are more similar to correct species histories than supertrees based on parsimony or Robinson–Foulds distance criteria. We successfully constructed an SPR supertree from a phylogenomic dataset of 40,631 gene trees that covered 244 genomes representing several major bacterial phyla. Our SPR-based approach also allowed direct inference of highways of gene transfer between bacterial classes and genera. A Small number of these highways connect genera in different phyla and can highlight specific genes implicated in long-distance LGT. [Lateral gene transfer; matrix representation with parsimony; phylogenomics; prokaryotic phylogeny; Robinson–Foulds; subtree prune-and-regraft; supertrees.] PMID:24695589

  17. Safe Use of Acoustic Vestibular-Evoked Myogenic Potential Stimuli: Protocol and Patient-Specific Considerations.

    PubMed

    Portnuff, Cory D F; Kleindienst, Samantha; Bogle, Jamie M

    2017-09-01

    Vestibular-evoked myogenic potentials (VEMPs) are commonly used clinical assessments for patients with complaints of dizziness. However, relatively high air-conducted stimuli are required to elicit the VEMP, and ultimately may compromise safe noise exposure limits. Recently, research has reported the potential for noise-induced hearing loss (NIHL) from VEMP stimulus exposure through studies of reduced otoacoustic emission levels after VEMP testing, as well as a recent case study showing permanent sensorineural hearing loss associated with VEMP exposure. The purpose of this report is to review the potential for hazardous noise exposure from VEMP stimuli and to suggest clinical parameters for safe VEMP testing. Literature review with presentation of clinical guidelines and a clinical tool for estimating noise exposure. The literature surrounding VEMP stimulus-induced hearing loss is reviewed, including several cases of overexposure. The article then presents a clinical calculation tool for the estimation of a patient's safe noise exposure from VEMP stimuli, considering stimulus parameters, and includes a discussion of how varying stimulus parameters affect a patient's noise exposure. Finally, recommendations are provided for recognizing and managing specific patient populations who may be at higher risk for NIHL from VEMP stimulus exposure. A sample protocol is provided that allows for safe noise exposure. VEMP stimuli have the potential to cause NIHL due to high sound exposure levels. However, with proper safety protocols in place, clinicians may reduce or eliminate this risk to their patients. Use of the tools provided, including the noise exposure calculation tool and sample protocols, may help clinicians to understand and ensure safe use of VEMP stimuli. American Academy of Audiology

  18. Detection of periodicity based on independence tests - III. Phase distance correlation periodogram

    NASA Astrophysics Data System (ADS)

    Zucker, Shay

    2018-02-01

    I present the Phase Distance Correlation (PDC) periodogram - a new periodicity metric, based on the Distance Correlation concept of Gábor Székely. For each trial period, PDC calculates the distance correlation between the data samples and their phases. PDC requires adaptation of the Székely's distance correlation to circular variables (phases). The resulting periodicity metric is best suited to sparse data sets, and it performs better than other methods for sawtooth-like periodicities. These include Cepheid and RR-Lyrae light curves, as well as radial velocity curves of eccentric spectroscopic binaries. The performance of the PDC periodogram in other contexts is almost as good as that of the Generalized Lomb-Scargle periodogram. The concept of phase distance correlation can be adapted also to astrometric data, and it has the potential to be suitable also for large evenly spaced data sets, after some algorithmic perfection.

  19. Estimation of Infiltration Parameters and the Irrigation Coefficients with the Surface Irrigation Advance Distance

    PubMed Central

    Beibei, Zhou; Quanjiu, Wang; Shuai, Tan

    2014-01-01

    A theory based on Manning roughness equation, Philip equation and water balance equation was developed which only employed the advance distance in the calculation of the infiltration parameters and irrigation coefficients in both the border irrigation and the surge irrigation. The improved procedure was validated with both the border irrigation and surge irrigation experiments. The main results are shown as follows. Infiltration parameters of the Philip equation could be calculated accurately only using water advance distance in the irrigation process comparing to the experimental data. With the calculated parameters and the water balance equation, the irrigation coefficients were also estimated. The water advance velocity should be measured at about 0.5 m to 1.0 m far from the water advance in the experimental corn fields. PMID:25061664

  20. Calculating lunar retreat rates using tidal rhythmites

    USGS Publications Warehouse

    Kvale, E.P.; Johnson, H.W.; Sonett, C.P.; Archer, A.W.; Zawistoski, A.N.N.

    1999-01-01

    Tidal rhythmites are small-scale sedimenta??r}- structures that can preserve a hierarchy of astronomically induced tidal periods. They can also preserve a record of periodic nontidal sedimentation. If properly interpreted and understood, tidal rhjthmites can be an important component of paleoastronomy and can be used to extract information on ancient lunar orbital dynamics including changes in Earth-Moon distance through geologic time. Herein we present techniques that can be used to calculate ancient Earth-Moon distances. Each of these techniques, when used on a modern high-tide data set, results in calculated estimates of lunar orbital periods and an EarthMoon distance that fall well within 1 percent of the actual values. Comparisons to results from modern tidal data indicate that ancient tidal rhythmite data as short as 4 months can provide suitable estimates of lunar orbital periods if these tidal records are complete. An understanding of basic tidal theory allows for the evaluation of completeness of the ancient tidal record as derived from an analysis of tidal rhythmites. Utilizing the techniques presented herein, it appears from the rock record that lunar orbital retreat slowed sometime during the midPaleozoic. Copyright ??1999, SEPM (Society for Sedimentary Geology).

  1. Safely Intake Number of Macridiscus sp. (Kerang Ceplos) from Tambak Lorok Waters, Semarang, Central Java, Indonesia

    NASA Astrophysics Data System (ADS)

    Meirenno Tielman, Eduard; Suprijanto, Jusup; Widowati, Ita

    2018-02-01

    The dynamics pollution that supposed to be derived from industrial activities around Tambak Lorok waters will affect the quality of waters, and also biota such as Macridiscus sp. mussels (Kerang Ceplos) that live and accumulate pollutants such as heavy metals (Pb, Cu, Al, Mn and Fe). However, Macridiscus sp. mussels which have been contaminated by heavy metals is usually sold for consumption by the people and if they consume it in excess, it will be toxic in the people’s body. So that, this study was to analyze Safely Intake Number of Macridiscus sp. from Tambak Lorok waters. This study used AAS (Atomic Absorption Spectrophotometry) method to analyze the accumulation number of the pollutant (Pb, Cu, Al, Mn and Fe). Safely Intake Number calculation is used MWI (Maximal Weekly Intake) and MTI (Maximal Tolerable Intake) calculation method. The results of AAS showed that the highest numbers of pollutant was Al (reached 534,51 mg/kg in the body of Macridiscus sp. that taken in February, 2016) and has exceeded the safely intake number (MWI Al = 1 mg/kg, based on WHO/FAO) so that it’s MTI values was low (0,08 kg/week/person). It means that Macridiscus sp. was not safe to be consumed excessively at that time.

  2. Dissolution comparisons using a Multivariate Statistical Distance (MSD) test and a comparison of various approaches for calculating the measurements of dissolution profile comparison.

    PubMed

    Cardot, J-M; Roudier, B; Schütz, H

    2017-07-01

    The f 2 test is generally used for comparing dissolution profiles. In cases of high variability, the f 2 test is not applicable, and the Multivariate Statistical Distance (MSD) test is frequently proposed as an alternative by the FDA and EMA. The guidelines provide only general recommendations. MSD tests can be performed either on raw data with or without time as a variable or on parameters of models. In addition, data can be limited-as in the case of the f 2 test-to dissolutions of up to 85% or to all available data. In the context of the present paper, the recommended calculation included all raw dissolution data up to the first point greater than 85% as a variable-without the various times as parameters. The proposed MSD overcomes several drawbacks found in other methods.

  3. Evaluation of laser-induced breakdown spectroscopy analysis potential for addressing radiological threats from a distance

    NASA Astrophysics Data System (ADS)

    Gaona, I.; Serrano, J.; Moros, J.; Laserna, J. J.

    2014-06-01

    Although radioactive materials are nowadays valuable tools in nearly all fields of modern science and technology, the dangers stemming from the uncontrolled use of ionizing radiation are more than evident. Since preparedness is a key issue to face the risks of a radiation dispersal event, development of rapid and efficient monitoring technologies to control the contamination caused by radioactive materials is of crucial interest. Laser-induced breakdown spectroscopy (LIBS) exhibits appealing features for this application. This research focuses on the assessment of LIBS potential for the in-situ fingerprinting and identification of radioactive material surrogates from a safe distance. LIBS selectivity and sensitivity to detect a variety of radioactive surrogates, namely 59Co, 88Sr, 130Ba, 133Cs, 193Ir and 238U, on the surface of common urban materials at a distance of 30 m have been evaluated. The performance of the technique for nuclear forensics has been also studied on different model scenarios. Findings have revealed the difficulties to detect and to identify the analytes depending on the surface being interrogated. However, as demonstrated, LIBS shows potential enough for prompt and accurate gathering of essential evidence at a number of sites after the release, either accidental or intentional, of radioactive material. The capability of standoff analysis confers to LIBS unique advantages in terms of fast and safe inspection of forensic scenarios. The identity of the radioactive surrogates is easily assigned from a distance and the sensitivity to their detection is in the range of a few hundreds of ng per square centimeter.

  4. Monte Carlo dose calculations of beta-emitting sources for intravascular brachytherapy: a comparison between EGS4, EGSnrc, and MCNP.

    PubMed

    Wang, R; Li, X A

    2001-02-01

    The dose parameters for the beta-particle emitting 90Sr/90Y source for intravascular brachytherapy (IVBT) have been calculated by different investigators. At a distant distance from the source, noticeable differences are seen in these parameters calculated using different Monte Carlo codes. The purpose of this work is to quantify as well as to understand these differences. We have compared a series of calculations using an EGS4, an EGSnrc, and the MCNP Monte Carlo codes. Data calculated and compared include the depth dose curve for a broad parallel beam of electrons, and radial dose distributions for point electron sources (monoenergetic or polyenergetic) and for a real 90Sr/90Y source. For the 90Sr/90Y source, the doses at the reference position (2 mm radial distance) calculated by the three code agree within 2%. However, the differences between the dose calculated by the three codes can be over 20% in the radial distance range interested in IVBT. The difference increases with radial distance from source, and reaches 30% at the tail of dose curve. These differences may be partially attributed to the different multiple scattering theories and Monte Carlo models for electron transport adopted in these three codes. Doses calculated by the EGSnrc code are more accurate than those by the EGS4. The two calculations agree within 5% for radial distance <6 mm.

  5. Distance Courses in Mechanics and in Distance Instructor Training

    ERIC Educational Resources Information Center

    Karlsson, Goran

    2004-01-01

    This paper describes two related distance courses for instructor and leadership training and a distance undergraduate course in mechanics. Flexible and distance learning are becoming more and more important, so it is important to train instructors for such changes. KTH (Royal Institute of Technology, Stockholm) has the course "5C4502 Distance…

  6. Spatial interpolation of river channel topography using the shortest temporal distance

    NASA Astrophysics Data System (ADS)

    Zhang, Yanjun; Xian, Cuiling; Chen, Huajin; Grieneisen, Michael L.; Liu, Jiaming; Zhang, Minghua

    2016-11-01

    It is difficult to interpolate river channel topography due to complex anisotropy. As the anisotropy is often caused by river flow, especially the hydrodynamic and transport mechanisms, it is reasonable to incorporate flow velocity into topography interpolator for decreasing the effect of anisotropy. In this study, two new distance metrics defined as the time taken by water flow to travel between two locations are developed, and replace the spatial distance metric or Euclidean distance that is currently used to interpolate topography. One is a shortest temporal distance (STD) metric. The temporal distance (TD) of a path between two nodes is calculated by spatial distance divided by the tangent component of flow velocity along the path, and the STD is searched using the Dijkstra algorithm in all possible paths between two nodes. The other is a modified shortest temporal distance (MSTD) metric in which both the tangent and normal components of flow velocity were combined. They are used to construct the methods for the interpolation of river channel topography. The proposed methods are used to generate the topography of Wuhan Section of Changjiang River and compared with Universal Kriging (UK) and Inverse Distance Weighting (IDW). The results clearly showed that the STD and MSTD based on flow velocity were reliable spatial interpolators. The MSTD, followed by the STD, presents improvement in prediction accuracy relative to both UK and IDW.

  7. Probing sunspots with two-skip time-distance helioseismology

    NASA Astrophysics Data System (ADS)

    Duvall, Thomas L., Jr.; Cally, Paul S.; Przybylski, Damien; Nagashima, Kaori; Gizon, Laurent

    2018-06-01

    Context. Previous helioseismology of sunspots has been sensitive to both the structural and magnetic aspects of sunspot structure. Aims: We aim to develop a technique that is insensitive to the magnetic component so the two aspects can be more readily separated. Methods: We study waves reflected almost vertically from the underside of a sunspot. Time-distance helioseismology was used to measure travel times for the waves. Ray theory and a detailed sunspot model were used to calculate travel times for comparison. Results: It is shown that these large distance waves are insensitive to the magnetic field in the sunspot. The largest travel time differences for any solar phenomena are observed. Conclusions: With sufficient modeling effort, these should lead to better understanding of sunspot structure.

  8. Safe Grid

    NASA Technical Reports Server (NTRS)

    Chow, Edward T.; Stewart, Helen; Korsmeyer, David (Technical Monitor)

    2003-01-01

    The biggest users of GRID technologies came from the science and technology communities. These consist of government, industry and academia (national and international). The NASA GRID is moving into a higher technology readiness level (TRL) today; and as a joint effort among these leaders within government, academia, and industry, the NASA GRID plans to extend availability to enable scientists and engineers across these geographical boundaries collaborate to solve important problems facing the world in the 21 st century. In order to enable NASA programs and missions to use IPG resources for program and mission design, the IPG capabilities needs to be accessible from inside the NASA center networks. However, because different NASA centers maintain different security domains, the GRID penetration across different firewalls is a concern for center security people. This is the reason why some IPG resources are been separated from the NASA center network. Also, because of the center network security and ITAR concerns, the NASA IPG resource owner may not have full control over who can access remotely from outside the NASA center. In order to obtain organizational approval for secured remote access, the IPG infrastructure needs to be adapted to work with the NASA business process. Improvements need to be made before the IPG can be used for NASA program and mission development. The Secured Advanced Federated Environment (SAFE) technology is designed to provide federated security across NASA center and NASA partner's security domains. Instead of one giant center firewall which can be difficult to modify for different GRID applications, the SAFE "micro security domain" provide large number of professionally managed "micro firewalls" that can allow NASA centers to accept remote IPG access without the worry of damaging other center resources. The SAFE policy-driven capability-based federated security mechanism can enable joint organizational and resource owner approved remote

  9. Recent skyshine calculations at Jefferson Lab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Degtyarenko, P.

    1997-12-01

    New calculations of the skyshine dose distribution of neutrons and secondary photons have been performed at Jefferson Lab using the Monte Carlo method. The dose dependence on neutron energy, distance to the neutron source, polar angle of a source neutron, and azimuthal angle between the observation point and the momentum direction of a source neutron have been studied. The azimuthally asymmetric term in the skyshine dose distribution is shown to be important in the dose calculations around high-energy accelerator facilities. A parameterization formula and corresponding computer code have been developed which can be used for detailed calculations of the skyshinemore » dose maps.« less

  10. Facilitating Distance Education.

    ERIC Educational Resources Information Center

    Rossman, Mark H., Ed.; Rossman, Maxine E., Ed.

    1995-01-01

    This collection of articles on distance learning reflects the perspectives and concerns of the learner and the facilitator of learning in distance education setting. Eight chapters are included: (1) "The Evolution and Advantages of Distance Education" (John E. Cantelon) traces the history of distance education and demonstrates how it transcends…

  11. Censoring distances based on labeled cortical distance maps in cortical morphometry.

    PubMed

    Ceyhan, Elvan; Nishino, Tomoyuki; Alexopolous, Dimitrios; Todd, Richard D; Botteron, Kelly N; Miller, Michael I; Ratnanather, J Tilak

    2013-01-01

    It has been demonstrated that shape differences in cortical structures may be manifested in neuropsychiatric disorders. Such morphometric differences can be measured by labeled cortical distance mapping (LCDM) which characterizes the morphometry of the laminar cortical mantle of cortical structures. LCDM data consist of signed/labeled distances of gray matter (GM) voxels with respect to GM/white matter (WM) surface. Volumes and other summary measures for each subject and the pooled distances can help determine the morphometric differences between diagnostic groups, however they do not reveal all the morphometric information contained in LCDM distances. To extract more information from LCDM data, censoring of the pooled distances is introduced for each diagnostic group where the range of LCDM distances is partitioned at a fixed increment size; and at each censoring step, the distances not exceeding the censoring distance are kept. Censored LCDM distances inherit the advantages of the pooled distances but also provide information about the location of morphometric differences which cannot be obtained from the pooled distances. However, at each step, the censored distances aggregate, which might confound the results. The influence of data aggregation is investigated with an extensive Monte Carlo simulation analysis and it is demonstrated that this influence is negligible. As an illustrative example, GM of ventral medial prefrontal cortices (VMPFCs) of subjects with major depressive disorder (MDD), subjects at high risk (HR) of MDD, and healthy control (Ctrl) subjects are used. A significant reduction in laminar thickness of the VMPFC in MDD and HR subjects is observed compared to Ctrl subjects. Moreover, the GM LCDM distances (i.e., locations with respect to the GM/WM surface) for which these differences start to occur are determined. The methodology is also applicable to LCDM-based morphometric measures of other cortical structures affected by disease.

  12. Training for Distance Teaching through Distance Learning.

    ERIC Educational Resources Information Center

    Cadorath, Jill; Harris, Simon; Encinas, Fatima

    2002-01-01

    Describes a mixed-mode bachelor degree course in English language teaching at the Universidad Autonoma de Puebla (Mexico) that was designed to help practicing teachers write appropriate distance education materials by giving them the experience of being distance students. Includes a course outline and results of a course evaluation. (Author/LRW)

  13. Safe Manual Jettison

    NASA Technical Reports Server (NTRS)

    Barton, Jay

    2008-01-01

    In space, the controlled release of certain cargoes is no less useful than the maritime jettisons from which they take their name but is also much more dangerous. Experience has shown that jettisons can be performed safely, but the process is complicated with the path to performing a jettison taking months or even years. In the background, time is also required to write procedures, train the crew, configure the vehicle, and many other activities. This paper outlines the current process used by the National Aeronautics and Space Administration (NASA) for manual jettisons, detailing the methods used to assure that the jettisons and the jettisoned objects are as safe as achievable and that the crew is adequately trained to be able to affect the safe jettison. The goal of this paper is not only to capture what it takes to perform safe jettisons in the near Earth environment but to extrapolate this knowledge to future space exploration scenarios that will likely have Extravehicular Activity (EVA) and International Partner (IP) interfaces.

  14. Analytic processing of distance.

    PubMed

    Dopkins, Stephen; Galyer, Darin

    2018-01-01

    How does a human observer extract from the distance between two frontal points the component corresponding to an axis of a rectangular reference frame? To find out we had participants classify pairs of small circles, varying on the horizontal and vertical axes of a computer screen, in terms of the horizontal distance between them. A response signal controlled response time. The error rate depended on the irrelevant vertical as well as the relevant horizontal distance between the test circles with the relevant distance effect being larger than the irrelevant distance effect. The results implied that the horizontal distance between the test circles was imperfectly extracted from the overall distance between them. The results supported an account, derived from the Exemplar Based Random Walk model (Nosofsky & Palmieri, 1997), under which distance classification is based on the overall distance between the test circles, with relevant distance being extracted from overall distance to the extent that the relevant and irrelevant axes are differentially weighted so as to reduce the contribution of irrelevant distance to overall distance. The results did not support an account, derived from the General Recognition Theory (Ashby & Maddox, 1994), under which distance classification is based on the relevant distance between the test circles, with the irrelevant distance effect arising because a test circle's perceived location on the relevant axis depends on its location on the irrelevant axis, and with relevant distance being extracted from overall distance to the extent that this dependency is absent. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Distancing, not embracing, the Distancing-Embracing model of art reception.

    PubMed

    Davies, Stephen

    2017-01-01

    Despite denials in the target article, the Distancing-Embracing model appeals to compensatory ideas in explaining the appeal of artworks that elicit negative affect. The model also appeals to the deflationary effects of psychological distancing. Having pointed to the famous rejection in the 1960s of the view that aesthetic experience involves psychological distancing, I suggest that "distance" functions here as a weak metaphor that cannot sustain the explanatory burden the theory demands of it.

  16. Foundations of Distance Education. Third Edition. Routledge Studies in Distance Education.

    ERIC Educational Resources Information Center

    Keegan, Desmond

    This text gives an overview of distance education for students, administrators, and practitioners in distance education. Chapter 1 discusses the study of distance education. Chapter 2 analyzes forms of nonconventional education (open, nontraditional) that may have similarities to distance education but are not to be identified with it. Chapter 3…

  17. Phylo_dCor: distance correlation as a novel metric for phylogenetic profiling.

    PubMed

    Sferra, Gabriella; Fratini, Federica; Ponzi, Marta; Pizzi, Elisabetta

    2017-09-05

    Elaboration of powerful methods to predict functional and/or physical protein-protein interactions from genome sequence is one of the main tasks in the post-genomic era. Phylogenetic profiling allows the prediction of protein-protein interactions at a whole genome level in both Prokaryotes and Eukaryotes. For this reason it is considered one of the most promising methods. Here, we propose an improvement of phylogenetic profiling that enables handling of large genomic datasets and infer global protein-protein interactions. This method uses the distance correlation as a new measure of phylogenetic profile similarity. We constructed robust reference sets and developed Phylo-dCor, a parallelized version of the algorithm for calculating the distance correlation that makes it applicable to large genomic data. Using Saccharomyces cerevisiae and Escherichia coli genome datasets, we showed that Phylo-dCor outperforms phylogenetic profiling methods previously described based on the mutual information and Pearson's correlation as measures of profile similarity. In this work, we constructed and assessed robust reference sets and propose the distance correlation as a measure for comparing phylogenetic profiles. To make it applicable to large genomic data, we developed Phylo-dCor, a parallelized version of the algorithm for calculating the distance correlation. Two R scripts that can be run on a wide range of machines are available upon request.

  18. Lidar Systems for Precision Navigation and Safe Landing on Planetary Bodies

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin; Pierrottet, Diego F.; Petway, Larry B.; Hines, Glenn D.; Roback, Vincent E.

    2011-01-01

    The ability of lidar technology to provide three-dimensional elevation maps of the terrain, high precision distance to the ground, and approach velocity can enable safe landing of robotic and manned vehicles with a high degree of precision. Currently, NASA is developing novel lidar sensors aimed at needs of future planetary landing missions. These lidar sensors are a 3-Dimensional Imaging Flash Lidar, a Doppler Lidar, and a Laser Altimeter. The Flash Lidar is capable of generating elevation maps of the terrain that indicate hazardous features such as rocks, craters, and steep slopes. The elevation maps collected during the approach phase of a landing vehicle, at about 1 km above the ground, can be used to determine the most suitable safe landing site. The Doppler Lidar provides highly accurate ground relative velocity and distance data allowing for precision navigation to the landing site. Our Doppler lidar utilizes three laser beams pointed to different directions to measure line of sight velocities and ranges to the ground from altitudes of over 2 km. Throughout the landing trajectory starting at altitudes of about 20 km, the Laser Altimeter can provide very accurate ground relative altitude measurements that are used to improve the vehicle position knowledge obtained from the vehicle navigation system. At altitudes from approximately 15 km to 10 km, either the Laser Altimeter or the Flash Lidar can be used to generate contour maps of the terrain, identifying known surface features such as craters, to perform Terrain relative Navigation thus further reducing the vehicle s relative position error. This paper describes the operational capabilities of each lidar sensor and provides a status of their development. Keywords: Laser Remote Sensing, Laser Radar, Doppler Lidar, Flash Lidar, 3-D Imaging, Laser Altimeter, Precession Landing, Hazard Detection

  19. Estimating the Distance to the Moon--Its Relevance to Mathematics. Core-Plus Mathematics Project.

    ERIC Educational Resources Information Center

    Stern, David P.

    This document features an activity for estimating the distance from the earth to the moon during a solar eclipse based on calculations performed by the ancient Greek astronomer Hipparchus. Historical, mathematical, and scientific details about the calculation are provided. Internet resources for teachers to obtain more information on the subject…

  20. A mathematical simulation of the tip-apex distance and the calcar-referenced tip-apex distance for intertrochanteric fractures reduced with lag screws.

    PubMed

    Li, Shuang; Chang, Shi-Min; Jin, Yan-Min; Zhang, Ying-Qi; Niu, Wen-Xin; Du, Shou-Chao; Zhang, Li-Zhi; Ma, Hui

    2016-06-01

    As a predictor of the risk of lag screw cutout, it was recommended that keeping tip-apex distance (TAD)<25mm and placing the screw centrally or inferiorly, but positioning the lag screw too inferiorly in the head would produce TAD>25mm. We aim to simulate various positions of the lag screw in the femoral head and identify whether 25mm is a suitable cut-off value that favours all sizes of femoral heads with intertrochanteric fractures of the hip. Using a general mathematical software, the positions of the screw tip points were simulated. The virtual anterior-posterior and lateral views were then visualised, and the locus of the screw tips was projected into a Cartesian coordinate system according to the TAD and calcar-referenced tip-apex distance (CalTAD) formulas. Each original virtual anterior-posterior and lateral image was zoomed and compiled to match a calculated average image. The screw tip points were recorded, traced and compiled into volumes which could be used to visualise the screw's movements and positioning within the femoral head. The extracted volumes were calculated when 10mmcalculated. Suitable positions for the screw tip were then assessed. For the TAD calculation, the shape of the traced screw tip points had a pancake-like appearance, while the CalTAD plot produced a teardrop-shaped region. The volume ratios of TAD, CalTAD and overlapping region relative to the femoral head volume were respectively 3.51±1.30%, 5.19±1.62% and 2.64±1.32%. The volumes of the traced TAD, CalTAD and overlapping regions increased slower than the volume of an idealised sphere. Positioning the lag screw should address geometrical effects of both tip-apex distance and femoral head size, with an emphasis on measuring the position of the screw tip for the suitable zone by volume ratio. The previous 25mm TAD cut-off value should be adjusted according to the individual femoral head

  1. Normative Values for Near and Distance Clinical Tests of Stereoacuity.

    PubMed

    Piano, Marianne E F; Tidbury, Laurence P; O'Connor, Anna R

    2016-12-01

    Extensive literature exists on normative stereoacuity values for younger children, but there is less information about normative stereoacuity in older children/adults. Individual stereotests cannot be used interchangeably-knowing the upper limit of normality for each test is important. This report details normative stereoacuity values for 5 near/distance stereotests drawn from a large sample of participants aged 16-40 years, across 3 studies. Participants (n=206, mean age 22.18±5.31 years) were administered the following stereotests: TNO, Preschool Randot, Frisby, Distance Randot, and Frisby-Davis 2. Medians and upper limits were calculated for each test. Upper limits for each stereotest were as follows: TNO (n=127, upper limit=120" arc), Preschool Randot (PSR, n=206, upper limit=70" arc), Frisby (n=206, upper limit=40" arc), Distance Randot (n=127, upper limit=160" arc), and Frisby-Davis 2 (n=109, upper limit=25" arc). Normative values for each stereotest are identified and discussed with respect to other studies. Potential sources of variation between tests, within testing distances, are also discussed.

  2. The Development of Teaching Efficacy for Drug-Dosage Calculation Instruction: A Nursing Faculty Perspective

    ERIC Educational Resources Information Center

    Vitale, Gail A.

    2011-01-01

    The purpose of this study was to examine how nursing efficacy for drug-dosage calculation instruction is determined. Medication administration is a critical function of nurses in healthcare settings. An essential component of safe medication administration is accurate drug-dosage calculation, but instruction in drug-dosage calculation methods…

  3. An empirical formula to calculate the full energy peak efficiency of scintillation detectors.

    PubMed

    Badawi, Mohamed S; Abd-Elzaher, Mohamed; Thabet, Abouzeid A; El-khatib, Ahmed M

    2013-04-01

    This work provides an empirical formula to calculate the FEPE for different detectors using the effective solid angle ratio derived from experimental measurements. The full energy peak efficiency (FEPE) curves of the (2″(*)2″) NaI(Tl) detector at different seven axial distances from the detector were depicted in a wide energy range from 59.53 to 1408keV using standard point sources. The distinction was based on the effects of the source energy and the source-to-detector distance. A good agreement was noticed between the measured and calculated efficiency values for the source-to-detector distances at 20, 25, 30, 35, 40, 45 and 50cm. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Distance to Dark Bodies

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Using the unique orbit of NASA's Spitzer Space Telescope and a depth-perceiving trick called parallax, astronomers have determined the distance to an invisible Milky Way object called OGLE-2005-SMC-001. This artist's concept illustrates how this trick works: different views from both Spitzer and telescopes on Earth are combined to give depth perception.

    Our Milky Way galaxy is heavier than it looks, and scientists use the term 'dark matter' to describe all the 'heavy stuff' in the universe that seems to be present but invisible to our telescopes. While much of this dark matter is likely made up of exotic materials, different from the ordinary particles that make up the world around us, some may consist of dark celestial bodies -- like planets, black holes, or failed stars -- that do not produce light or are too faint to detect from Earth. OGLE-2005-SMC-001 is one of these dark celestial bodies.

    Although astronomers cannot see a dark body, they can sense its presence from the way light acts around it. When a dark body like OGLE-2005-SMC-001 passes in front of a bright star, its gravity causes the background starlight to bend and brighten, a process called gravitational microlensing. When the observing telescope, dark body, and star system are closely aligned, the microlensing event reaches maximum, or peak, brightness.

    A team of astronomers first sensed OGLE-2005-SMC-001's presence when it passed in front of a star in a neighboring satellite galaxy called the Small Magellanic Cloud. In this artist's rendering, the satellite galaxy is depicted as the fuzzy structure sitting to the left of Earth. Once they detected this microlensing event, the scientists used Spitzer and the principle of parallax to figure out its distance. Humans naturally use parallax to determine distance. Each eye sees the distance of an object differently. The brain takes each eye's perspective and instantaneously calculates how far away the object is.

    To determine OGLE

  5. SLOPE STABILITY EVALUATION AND EQUIPMENT SETBACK DISTANCES FOR BURIAL GROUND EXCAVATIONS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    MCSHANE DS

    2010-03-25

    After 1970 Transuranic (TRU) and suspect TRU waste was buried in the ground with the intention that at some later date the waste would be retrieved and processed into a configuration for long term storage. To retrieve this waste the soil must be removed (excavated). Sloping the bank of the excavation is the method used to keep the excavation from collapsing and to provide protection for workers retrieving the waste. The purpose of this paper is to document the minimum distance (setback) that equipment must stay from the edge of the excavation to maintain a stable slope. This evaluation examinesmore » the equipment setback distance by dividing the equipment into two categories, (1) equipment used for excavation and (2) equipment used for retrieval. The section on excavation equipment will also discuss techniques used for excavation including the process of benching. Calculations 122633-C-004, 'Slope Stability Analysis' (Attachment A), and 300013-C-001, 'Crane Stability Analysis' (Attachment B), have been prepared to support this evaluation. As shown in the calculations the soil has the following properties: Unit weight 110 pounds per cubic foot; and Friction Angle (natural angle of repose) 38{sup o} or 1.28 horizontal to 1 vertical. Setback distances are measured from the top edge of the slope to the wheels/tracks of the vehicles and heavy equipment being utilized. The computer program utilized in the calculation uses the center of the wheel or track load for the analysis and this difference is accounted for in this evaluation.« less

  6. Traversing psychological distance.

    PubMed

    Liberman, Nira; Trope, Yaacov

    2014-07-01

    Traversing psychological distance involves going beyond direct experience, and includes planning, perspective taking, and contemplating counterfactuals. Consistent with this view, temporal, spatial, and social distances as well as hypotheticality are associated, affect each other, and are inferred from one another. Moreover, traversing all distances involves the use of abstraction, which we define as forming a belief about the substitutability for a specific purpose of subjectively distinct objects. Indeed, across many instances of both abstraction and psychological distancing, more abstract constructs are used for more distal objects. Here, we describe the implications of this relation for prediction, choice, communication, negotiation, and self-control. We ask whether traversing distance is a general mental ability and whether distance should replace expectancy in expected-utility theories. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. VegeSafe: A community science program measuring soil-metal contamination, evaluating risk and providing advice for safe gardening.

    PubMed

    Rouillon, Marek; Harvey, Paul J; Kristensen, Louise J; George, Steven G; Taylor, Mark P

    2017-03-01

    The extent of metal contamination in Sydney residential garden soils was evaluated using data collected during a three-year Macquarie University community science program called VegeSafe. Despite knowledge of industrial and urban contamination amongst scientists, the general public remains under-informed about the potential risks of exposure from legacy contaminants in their home garden environment. The community was offered free soil metal screening, allowing access to soil samples for research purposes. Participants followed specific soil sampling instructions and posted samples to the University for analysis with a field portable X-ray Fluorescence (pXRF) spectrometer. Over the three-year study period, >5200 soil samples, primarily from vegetable gardens, were collected from >1200 Australian homes. As anticipated, the primary soil metal of concern was lead; mean concentrations were 413 mg/kg (front yard), 707 mg/kg (drip line), 226 mg/kg (back yard) and 301 mg/kg (vegetable garden). The Australian soil lead guideline of 300 mg/kg for residential gardens was exceeded at 40% of Sydney homes, while concentrations >1000 mg/kg were identified at 15% of homes. The incidence of highest soil lead contamination was greatest in the inner city area with concentrations declining towards background values of 20-30 mg/kg at 30-40 km distance from the city. Community engagement with VegeSafe participants has resulted in useful outcomes: dissemination of knowledge related to contamination legacies and health risks; owners building raised beds containing uncontaminated soil and in numerous cases, owners replacing all of their contaminated soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Calculated dipole moment and energy in collision of a hydrogen molecule and a hydrogen atom

    NASA Technical Reports Server (NTRS)

    Patch, R. W.

    1973-01-01

    Calculations were carried out using three Slater-type 1s orbitals in the orthogonalized valencebond theory of McWeeny. Each orbital exponent was optimized, the H2 internuclear distance was varied from 7.416 x 10 to the -11th power to 7.673 x 10 to the -11th power m (1.401 to 1.450 bohrs). The intermolecular distance was varied from 1 to 4 bohrs (0.5292 to 2.117 x 10 to the 10th power). Linear, scalene, and isosceles configurations were used. A weighted average of the interaction energies was taken for each intermolecular distance. Although energies are tabulated, the principal purpose was to calculate the electric dipole moment and its derivative with respect to H2 internuclear distance.

  9. How Safe Is High-Speed Burring in Spine Surgery? An In Vitro Study on the Effect of Rotational Speed and Heat Generation in the Bovine Spine.

    PubMed

    Singh, Taran Singh Pall; Yusoff, Abdul Halim; Chian, Yap Keat

    2015-08-01

    In vitro animal cadaveric study. To identify the appropriate rotational speed and safe bone distance from neural tissue during bone burring in spinal surgery. Bone burring is a common step in spinal surgery. Unwanted frictional heat produced during bone burring may result in thermal injury to the bone and adjacent neural structure. One of the important parameters influencing the bone temperature rise during bone burring is rotational speed. This laboratory-based animal study used bovine spine bones, and the tests were conducted using a steel round burr. The bone temperature was measured simultaneously with thermocouple at the distances of 1 mm, 3 mm, and 5 mm from the burring site during the burring process. The bone burring was done with 4 different rotational speeds of 35,000 revolutions per minute (rpm), 45,000 rpm, 65,000 rpm, and 75,000 rpm. This study showed that increasing the rotational speed significantly elevated bone temperature. The threshold temperature of 47°C was reached when bone was burred for 10 seconds, with a rotational speed of 45,000 rpm. The mean bone temperature measured at a distance 1 mm from the burring site for all 4 rotational speeds was always higher than that measured at a distance of 3 mm and 5 mm and this difference was statistically significant (P < 0.001). There was no significant difference between the mean bone temperature measured at a distance of 3 mm and 5 mm (P > 0.05). Taking 47°C as the threshold temperature for causing significant impairment to the regenerative capacity of bone, a rotational speed of lower than 45,000 rpm is preferable so as to minimize thermal injury to bone tissue. We also concluded that a 3-mm distance between the site of burring and the neural tissue is a safe distance. N/A.

  10. Buying & Using Medicine Safely

    MedlinePlus

    ... Generic Drugs - Patient Education Resources Patient and Prescriber materials: Videos, PSAs, factsheets and more. Spotlight Drugs@FDA Index to Drug-Specific Information Protecting Yourself Safe Disposal of Medicines Generic Medicines – safe, effective and ...

  11. The relationship of travel distance with cystectomy access and outcomes.

    PubMed

    Smith, Angela B; Meyer, Anne-Marie; Meng, Ke; Nielsen, Matthew E; Pruthi, Raj; Wallen, Eric; Woods, Michael; Tan, Hung-Jui

    2018-06-01

    Regionalization of care and travel distance may result in unintended consequences for complex surgery such as cystectomy. Our objective was to evaluate effect of differential distance on cystectomy receipt among patients with muscle-invasive bladder cancer (MIBC) and investigate the association between travel distance and cystectomy outcomes such as readmission. Using a linked data resource combining the NC Central Cancer Registry with claims data from Medicare, Medicaid, and private insurance plans, we included 736 patients with MIBC and 1,082 who underwent cystectomy. To evaluate access, differential distance was calculated as the difference between the nearest urologist and nearest cystectomy provider. To assess outcomes, logistic regression was used to evaluate rehospitalization and major complications, and Cox proportional hazards model for survival analysis. To evaluate access and outcomes, 736 patients with MIBC and 1,082 patients undergoing cystectomy were evaluated, respectively. Overall, 29% (211 of 736) with MIBC underwent cystectomy. Differential distance was not a predictor of cystectomy receipt (odds ratio = 1.0; 95% CI: 1.00, 1.01). Among patients undergoing cystectomy, travel distance from cystectomy provider was not a significant predictor of 30- or 31 to 90day readmissions (odds ratio = 1.0; 95% CI: 1.00, 1.00) although patients who lived further from their cystectomy provider were more likely to be readmitted to a nonindex hospital (P<0.001) when controlling for other factors. Although travel distance did not have a significant effect on overall survival, patients readmitted between 31 to 90days had worse overall survival (P<0.0001). The additional distance needed to reach a cystectomy provider did not predict receipt of surgery for MIBC. Furthermore, travel distance from cystectomy provider was not a significant predictor for subsequent readmission after cystectomy and did not affect overall survival. Copyright © 2018 Elsevier Inc. All rights

  12. Using multiple travel paths to estimate daily travel distance in arboreal, group-living primates.

    PubMed

    Steel, Ruth Irene

    2015-01-01

    Primate field studies often estimate daily travel distance (DTD) in order to estimate energy expenditure and/or test foraging hypotheses. In group-living species, the center of mass (CM) method is traditionally used to measure DTD; a point is marked at the group's perceived center of mass at a set time interval or upon each move, and the distance between consecutive points is measured and summed. However, for groups using multiple travel paths, the CM method potentially creates a central path that is shorter than the individual paths and/or traverses unused areas. These problems may compromise tests of foraging hypotheses, since distance and energy expenditure could be underestimated. To better understand the magnitude of these potential biases, I designed and tested the multiple travel paths (MTP) method, in which DTD was calculated by recording all travel paths taken by the group's members, weighting each path's distance based on its proportional use by the group, and summing the weighted distances. To compare the MTP and CM methods, DTD was calculated using both methods in three groups of Udzungwa red colobus monkeys (Procolobus gordonorum; group size 30-43) for a random sample of 30 days between May 2009 and March 2010. Compared to the CM method, the MTP method provided significantly longer estimates of DTD that were more representative of the actual distance traveled and the areas used by a group. The MTP method is more time-intensive and requires multiple observers compared to the CM method. However, it provides greater accuracy for testing ecological and foraging models.

  13. CORSEN, a new software dedicated to microscope-based 3D distance measurements: mRNA-mitochondria distance, from single-cell to population analyses.

    PubMed

    Jourdren, Laurent; Delaveau, Thierry; Marquenet, Emelie; Jacq, Claude; Garcia, Mathilde

    2010-07-01

    Recent improvements in microscopy technology allow detection of single molecules of RNA, but tools for large-scale automatic analyses of particle distributions are lacking. An increasing number of imaging studies emphasize the importance of mRNA localization in the definition of cell territory or the biogenesis of cell compartments. CORSEN is a new tool dedicated to three-dimensional (3D) distance measurements from imaging experiments especially developed to access the minimal distance between RNA molecules and cellular compartment markers. CORSEN includes a 3D segmentation algorithm allowing the extraction and the characterization of the cellular objects to be processed--surface determination, aggregate decomposition--for minimal distance calculations. CORSEN's main contribution lies in exploratory statistical analysis, cell population characterization, and high-throughput assays that are made possible by the implementation of a batch process analysis. We highlighted CORSEN's utility for the study of relative positions of mRNA molecules and mitochondria: CORSEN clearly discriminates mRNA localized to the vicinity of mitochondria from those that are translated on free cytoplasmic polysomes. Moreover, it quantifies the cell-to-cell variations of mRNA localization and emphasizes the necessity for statistical approaches. This method can be extended to assess the evolution of the distance between specific mRNAs and other cellular structures in different cellular contexts. CORSEN was designed for the biologist community with the concern to provide an easy-to-use and highly flexible tool that can be applied for diverse distance quantification issues.

  14. Distance Education and Distance Learning: Some Psychological Considerations.

    ERIC Educational Resources Information Center

    Cropley, Arthur J.; Kahl, Thomas N.

    1983-01-01

    Compares and contrasts distance education and face-to-face education in terms of selected psychological dimensions, i.e., organization and learning, motivation, learning and communication processes, didactic activities and materials, and evaluation and feedback. Psychological aspects of distance education that may be favorable to learning are also…

  15. The effect of plyometric training on power and kicking distance in female adolescent soccer players.

    PubMed

    Rubley, Mack D; Haase, Amaris C; Holcomb, William R; Girouard, Tedd J; Tandy, Richard D

    2011-01-01

    The purpose of this study was to measure the effects of low-frequency, low-impact plyometric training on vertical jump (VJ) and kicking distance in female adolescent soccer players. Sixteen adolescent soccer players were studied (age 13.4 ± 0.5 years) across 14 weeks. The control group (general soccer training only) had 6 subjects, and the plyometric training (general soccer training plus plyometric exercise) group had 10 subjects. All subjects were tested for VJ and kicking distance on 3 occasions: pre-test, 7 weeks, and 14 weeks. Data were analyzed using a 2 (Training) × 3 (Test) analysis of variance (ANOVA) with repeated measures on the factor test. No significant difference in kicking distance was found between groups at pre-test (p = 0.688) or 7 weeks (p = 0.117). The plyometric group had significantly greater kicking distance after 14 weeks (p < 0.001). No significant difference in VJ height was found between groups at pre-test (p = 0.837) or 7 weeks (p = 0.108). The plyometric group had a significantly higher VJ after 14 weeks (p = 0.014). These results provide strength coaches with a safe and effective alternative to high-intensity plyometric training. Based on these findings, to increase lower-body power resulting in increased VJ and kicking distance, strength coaches should implement once-weekly, low-impact plyometric training programs with their adolescent athletes.

  16. Enhancing multi-view autostereoscopic displays by viewing distance control (VDC)

    NASA Astrophysics Data System (ADS)

    Jurk, Silvio; Duckstein, Bernd; Renault, Sylvain; Kuhlmey, Mathias; de la Barré, René; Ebner, Thomas

    2014-03-01

    Conventional multi-view displays spatially interlace various views of a 3D scene and form appropriate viewing channels. However, they only support sufficient stereo quality within a limited range around the nominal viewing distance (NVD). If this distance is maintained, two slightly divergent views are projected to the person's eyes, both covering the entire screen. With increasing deviations from the NVD the stereo image quality decreases. As a major drawback in usability, the manufacturer so far assigns this distance. We propose a software-based solution that corrects false view assignments depending on the distance of the viewer. Our novel approach enables continuous view adaptation based on the calculation of intermediate views and a column-bycolumn rendering method. The algorithm controls each individual subpixel and generates a new interleaving pattern from selected views. In addition, we use color-coded test content to verify its efficacy. This novel technology helps shifting the physically determined NVD to a user-defined distance thereby supporting stereopsis. The recent viewing positions can fall in front or behind the NVD of the original setup. Our algorithm can be applied to all multi-view autostereoscopic displays — independent of the ascent or the periodicity of the optical element. In general, the viewing distance can be corrected with a factor of more than 2.5. By creating a continuous viewing area the visualized 3D content is suitable even for persons with largely divergent intraocular distance — adults and children alike — without any deficiency in spatial perception.

  17. Calculation of the vibrational spectra of betaine hydrochloride

    NASA Astrophysics Data System (ADS)

    Szafran, Miroslaw; Koput, Jacek

    1997-02-01

    The molecular geometries of betaine hydrochloride, BET·HCl, and free protonated betaine, BET·H +, were calculated with the 6-31G(d,p) basis set at the SCF, MP2 and DFT levels of theory. At the SCF level, the minimum energy corresponds to the ionic pair, B +Htctdot;A -, however, the equilibrium Otctdot;Cl distance is 0.14 Å shorter than the X-ray value. Inclusion of the correlation effects, both at the MP2 and DFT levels, predicts a minimum energy for the molecular complex, Btctdot;H-A, with the equilibrium Otctdot;Cl distance close to the experimental value. The frequencies and intensities of the vibrational bands of BET·HCl, BET·DCl and BET·H + were calculated at the SCF and DFT levels and compared with the solid IR spectra. All measured IR bands were interpreted in term of the calculated vibrational modes. The rms deviations between the experimental and calculated SCF frequencies were 21 and 29 cm -1 for BET·HCl and BET·DCl, respectively. The computed band intensities agree qualitatively with the experimental data. The coupling of the CO stretching and OH bending modes are discussed. The summation bands are probably enhanced in intensity by Fermi resonance with the fundamentals responsible for the main ν(OH) (ν(OD) absorption region.

  18. Cultivating the Art of Safe Space

    ERIC Educational Resources Information Center

    Hunter, Mary Ann

    2008-01-01

    Performance-making and peace-building are processes predicated on the production of safe space. But what is "safe space"? In performance-making, what is it that makes space safe without losing the creative potential of tension? What role is there for risk? And, once achieved, how does safe space become meaningful beyond its immediate…

  19. Open and Distance Learning Today. Routledge Studies in Distance Education Series.

    ERIC Educational Resources Information Center

    Lockwood, Fred, Ed.

    This book contains the following papers on open and distance learning today: "Preface" (Daniel); "Big Bang Theory in Distance Education" (Hawkridge); "Practical Agenda for Theorists of Distance Education" (Perraton); "Trends, Directions and Needs: A View from Developing Countries" (Koul); "American…

  20. Safe Affordable Fission Engine-(SAFE-) 100a Heat Exchanger Thermal and Structural Analysis

    NASA Technical Reports Server (NTRS)

    Steeve, B. E.

    2005-01-01

    A potential fission power system for in-space missions is a heat pipe-cooled reactor coupled to a Brayton cycle. In this system, a heat exchanger (HX) transfers the heat of the reactor core to the Brayton gas. The Safe Affordable Fission Engine- (SAFE-) 100a is a test program designed to thermally and hydraulically simulate a 95 Btu/s prototypic heat pipe-cooled reactor using electrical resistance heaters on the ground. This Technical Memorandum documents the thermal and structural assessment of the HX used in the SAFE-100a program.

  1. Theme: Distance Education.

    ERIC Educational Resources Information Center

    Whittington, M. Susie, Ed.; And Others

    1994-01-01

    Includes "Next Best Thing to Being There" (Whittington); "Taking the Distance out of Distance Education" (Miller, King); "Preparing a Course for Distance Delivery" (Newcomb); "Team Teaching via Two-Way Interactive Video" (Nichols, Trout); "Using the Ag Ed Network" (Peal); "Student's Perspective" (Schoellhorn); "Need for Instruction in Agriculture…

  2. The importance of including local correlation times in the calculation of inter-proton distances from NMR measurements: ignoring local correlation times leads to significant errors in the conformational analysis of the Glc alpha1-2Glc alpha linkage by NMR spectroscopy.

    PubMed

    Mackeen, Mukram; Almond, Andrew; Cumpstey, Ian; Enis, Seth C; Kupce, Eriks; Butters, Terry D; Fairbanks, Antony J; Dwek, Raymond A; Wormald, Mark R

    2006-06-07

    The experimental determination of oligosaccharide conformations has traditionally used cross-linkage 1H-1H NOE/ROEs. As relatively few NOEs are observed, to provide sufficient conformational constraints this method relies on: accurate quantification of NOE intensities (positive constraints); analysis of absent NOEs (negative constraints); and hence calculation of inter-proton distances using the two-spin approximation. We have compared the results obtained by using 1H 2D NOESY, ROESY and T-ROESY experiments at 500 and 700 MHz to determine the conformation of the terminal Glc alpha1-2Glc alpha linkage in a dodecasaccharide and a related tetrasaccharide. For the tetrasaccharide, the NOESY and ROESY spectra produced the same qualitative pattern of linkage cross-peaks but the quantitative pattern, the relative peak intensities, was different. For the dodecasaccharide, the NOESY and ROESY spectra at 500 MHz produced a different qualitative pattern of linkage cross-peaks, with fewer peaks in the NOESY spectrum. At 700 MHz, the NOESY and ROESY spectra of the dodecasaccharide produced the same qualitative pattern of peaks, but again the relative peak intensities were different. These differences are due to very significant differences in the local correlation times for different proton pairs across this glycosidic linkage. The local correlation time for each proton pair was measured using the ratio of the NOESY and T-ROESY cross-relaxation rates, leaving the NOESY and ROESY as independent data sets for calculating the inter-proton distances. The inter-proton distances calculated including the effects of differences in local correlation times give much more consistent results.

  3. Breastfeeding FAQs: Safely Storing Breast Milk

    MedlinePlus

    ... Staying Safe Videos for Educators Search English Español Breastfeeding FAQs: Safely Storing Breast Milk KidsHealth / For Parents / Breastfeeding FAQs: Safely Storing Breast Milk What's in this ...

  4. From a distance: implications of spontaneous self-distancing for adaptive self-reflection.

    PubMed

    Ayduk, Ozlem; Kross, Ethan

    2010-05-01

    Although recent experimental work indicates that self-distancing facilitates adaptive self-reflection, it remains unclear (a) whether spontaneous self-distancing leads to similar adaptive outcomes, (b) how spontaneous self-distancing relates to avoidance, and (c) how this strategy impacts interpersonal behavior. Three studies examined these issues demonstrating that the more participants spontaneously self-distanced while reflecting on negative memories, the less emotional (Studies 1-3) and cardiovascular (Study 2) reactivity they displayed in the short term. Spontaneous self-distancing was also associated with lower emotional reactivity and intrusive ideation over time (Study 1). The negative association between spontaneous self-distancing and emotional reactivity was mediated by how participants construed their experience (i.e., less recounting relative to reconstruing) rather than avoidance (Studies 1-2). In addition, spontaneous self-distancing was associated with more problem-solving behavior and less reciprocation of negativity during conflicts among couples in ongoing relationships (Study 3). Although spontaneous self-distancing was empirically related to trait rumination, it explained unique variance in predicting key outcomes. 2010 APA, all rights reserved

  5. From a distance: Implications of spontaneous self-distancing for adaptive self-reflection

    PubMed Central

    Ayduk, Özlem; Kross, Ethan

    2010-01-01

    Although recent work experimental work indicates that self-distancing facilitates adaptive self-reflection, it remains unclear (a) whether spontaneously self-distancing leads to similar adaptive outcomes, (b) how spontaneous self-distancing relates to avoidance, and (c) how this strategy impacts interpersonal behavior. Three studies examined these issues demonstrating that the more participants spontaneously self-distanced while reflecting on negative memories, the less emotional (Studies 1–3) and cardiovascular (Study 2) reactivity they displayed in the short-term. Spontaneous self-distancing was also associated with lower emotional reactivity and intrusive ideation over time (Study 1). The negative association between spontaneous self-distancing and emotional reactivity was mediated by how participants construed their experience (i.e., less recounting relative to reconstruing) rather than avoidance (Studies 1–2). In addition, spontaneous self-distancing was associated with more problem-solving behavior and less reciprocation of negativity during conflicts among couples in ongoing relationships (Study 3). Although spontaneous self-distancing was empirically related to trait rumination, it explained unique variance in predicting key outcomes. PMID:20438226

  6. Connes distance function on fuzzy sphere and the connection between geometry and statistics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Devi, Yendrembam Chaoba, E-mail: chaoba@bose.res.in; Chakraborty, Biswajit, E-mail: biswajit@bose.res.in; Prajapat, Shivraj, E-mail: shraprajapat@gmail.com

    An algorithm to compute Connes spectral distance, adaptable to the Hilbert-Schmidt operatorial formulation of non-commutative quantum mechanics, was developed earlier by introducing the appropriate spectral triple and used to compute infinitesimal distances in the Moyal plane, revealing a deep connection between geometry and statistics. In this paper, using the same algorithm, the Connes spectral distance has been calculated in the Hilbert-Schmidt operatorial formulation for the fuzzy sphere whose spatial coordinates satisfy the su(2) algebra. This has been computed for both the discrete and the Perelemov’s SU(2) coherent state. Here also, we get a connection between geometry and statistics which ismore » shown by computing the infinitesimal distance between mixed states on the quantum Hilbert space of a particular fuzzy sphere, indexed by n ∈ ℤ/2.« less

  7. Glenoid morphology and the safe zone for protecting the suprascapular nerve during baseplate fixation in reverse shoulder arthroplasty.

    PubMed

    Yang, Yuhui; Zuo, Jianlin; Liu, Tong; Shao, Pu; Wu, Haihe; Gao, Zhongli; Xiao, Jianlin

    2018-03-01

    The purpose of this study was to investigate glenoid morphology and define the safe zone for protecting the suprascapular nerve baseplate screw during baseplate fixation in reverse shoulder arthroplasty (RSA) in a Chinese population. Shoulder computed tomography (CT) scans from 56 subjects were retrospectively reviewed. Three-dimensional (3D) reconstruction was performed using Mimics software, and corresponding bony references were used to evaluate glenoid morphology. To standardize evaluation, the coronal scapular plane was defined. Safe fixation distances and screw placements were investigated by constructing a simulated cutting plane of the baseplate during RSA. Mean glenoid height was 35.83 ± 2.95 mm, and width was 27.32 ± 2.78 mm, with significant sexual dimorphism (p < 0.01). According to the cutting plane morphology, the average baseplate radius was 13.84 ± 1.34 mm. The distances from the suprascapular notch and from two bony reference points at the base of the scapular spine to the cutting plane were 30.27 ± 2.77 mm, 18.39 ± 1.67 mm and 16.52 ± 1.52 mm, respectively, with a gender-related difference. Based on the clock face indication system, the danger zone caused by the suprascapular nerve projection was oriented between the two o'clock and eight o'clock positions in reference to the right shoulder. Glenoid size and the safe zone for screw fixation during RSA were characterized in a Chinese population. Careful consideration of baseplate fixation and avoidance of suprascapular nerve injury are important for improved clinical outcome.

  8. How to calculate H3 better.

    PubMed

    Pavanello, Michele; Tung, Wei-Cheng; Adamowicz, Ludwik

    2009-11-14

    Efficient optimization of the basis set is key to achieving a very high accuracy in variational calculations of molecular systems employing basis functions that are explicitly dependent on the interelectron distances. In this work we present a method for a systematic enlargement of basis sets of explicitly correlated functions based on the iterative-complement-interaction approach developed by Nakatsuji [Phys. Rev. Lett. 93, 030403 (2004)]. We illustrate the performance of the method in the variational calculations of H(3) where we use explicitly correlated Gaussian functions with shifted centers. The total variational energy (-1.674 547 421 Hartree) and the binding energy (-15.74 cm(-1)) obtained in the calculation with 1000 Gaussians are the most accurate results to date.

  9. Smartphone viewing distance and sleep: an experimental study utilizing motion capture technology

    PubMed Central

    Yoshimura, Michitaka; Kitazawa, Momoko; Maeda, Yasuhiro; Mimura, Masaru; Tsubota, Kazuo; Kishimoto, Taishiro

    2017-01-01

    There are studies reporting the negative impact of smartphone utilization on sleep. It is considered that reduction of melatonin secretion under the blue light exposure from smart-phone displays is one of the causes. The viewing distance may cause sleep disturbance, because the viewing distance determines the screen illuminance and/or asthenopia. However, to date, there has been no study closely investigating the impact of viewing distance on sleep; therefore, we sought to determine the relationship between smartphone viewing distance and subjective sleep status. Twenty-three nursing students (mean age ± standard deviation of 19.7±3.1 years) participated in the study. Subjective sleep status was assessed using the Pittsburgh Sleep Quality Index, morningness–eveningness questionnaire, and the Epworth sleepiness scale. We used the distance between the head and the hand while holding a smartphone to measure the viewing distance while using smartphones in sitting and lying positions. The distance was calculated using the three-dimensional coordinates obtained by a noncontact motion-sensing device. The viewing distance of smartphones in the sitting position ranged from 13.3 to 32.9 cm among participants. In the lying position, it ranged from 9.9 to 21.3cm. The viewing distance was longer in the sitting position than in the lying position (mean ± standard deviation: 20.3±4.7 vs 16.4±2.7, respectively, P<0.01). We found that the short viewing distance in the lying position had a positive correlation to a poorer sleep state (R2=0.27, P<0.05), lower sleep efficiency (R2=0.35, P<0.05), and longer sleep latency (R2=0.38, P<0.05). Moreover, smartphone viewing distances in lying position correlated negatively with subjective sleep status. Therefore, when recommending ideal smartphone use in lying position, one should take into account the viewing distances. PMID:28331379

  10. Smartphone viewing distance and sleep: an experimental study utilizing motion capture technology.

    PubMed

    Yoshimura, Michitaka; Kitazawa, Momoko; Maeda, Yasuhiro; Mimura, Masaru; Tsubota, Kazuo; Kishimoto, Taishiro

    2017-01-01

    There are studies reporting the negative impact of smartphone utilization on sleep. It is considered that reduction of melatonin secretion under the blue light exposure from smart-phone displays is one of the causes. The viewing distance may cause sleep disturbance, because the viewing distance determines the screen illuminance and/or asthenopia. However, to date, there has been no study closely investigating the impact of viewing distance on sleep; therefore, we sought to determine the relationship between smartphone viewing distance and subjective sleep status. Twenty-three nursing students (mean age ± standard deviation of 19.7±3.1 years) participated in the study. Subjective sleep status was assessed using the Pittsburgh Sleep Quality Index, morningness-eveningness questionnaire, and the Epworth sleepiness scale. We used the distance between the head and the hand while holding a smartphone to measure the viewing distance while using smartphones in sitting and lying positions. The distance was calculated using the three-dimensional coordinates obtained by a noncontact motion-sensing device. The viewing distance of smartphones in the sitting position ranged from 13.3 to 32.9 cm among participants. In the lying position, it ranged from 9.9 to 21.3cm. The viewing distance was longer in the sitting position than in the lying position (mean ± standard deviation: 20.3±4.7 vs 16.4±2.7, respectively, P <0.01). We found that the short viewing distance in the lying position had a positive correlation to a poorer sleep state ( R 2 =0.27, P <0.05), lower sleep efficiency ( R 2 =0.35, P <0.05), and longer sleep latency ( R 2 =0.38, P <0.05). Moreover, smartphone viewing distances in lying position correlated negatively with subjective sleep status. Therefore, when recommending ideal smartphone use in lying position, one should take into account the viewing distances.

  11. Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances.

    PubMed

    Fort, Florian; Jouany, Claire; Cruz, Pablo

    2015-01-01

    Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance.

  12. Hierarchical traits distances explain grassland Fabaceae species' ecological niches distances

    PubMed Central

    Fort, Florian; Jouany, Claire; Cruz, Pablo

    2015-01-01

    Fabaceae species play a key role in ecosystem functioning through their capacity to fix atmospheric nitrogen via their symbiosis with Rhizobium bacteria. To increase benefits of using Fabaceae in agricultural systems, it is necessary to find ways to evaluate species or genotypes having potential adaptations to sub-optimal growth conditions. We evaluated the relevance of phylogenetic distance, absolute trait distance and hierarchical trait distance for comparing the adaptation of 13 grassland Fabaceae species to different habitats, i.e., ecological niches. We measured a wide range of functional traits (root traits, leaf traits, and whole plant traits) in these species. Species phylogenetic and ecological distances were assessed from a species-level phylogenetic tree and species' ecological indicator values, respectively. We demonstrated that differences in ecological niches between grassland Fabaceae species were related more to their hierarchical trait distances than to their phylogenetic distances. We showed that grassland Fabaceae functional traits tend to converge among species with the same ecological requirements. Species with acquisitive root strategies (thin roots, shallow root systems) are competitive species adapted to non-stressful meadows, while conservative ones (coarse roots, deep root systems) are able to tolerate stressful continental climates. In contrast, acquisitive species appeared to be able to tolerate low soil-P availability, while conservative ones need high P availability. Finally we highlight that traits converge along the ecological gradient, providing the assumption that species with similar root-trait values are better able to coexist, regardless of their phylogenetic distance. PMID:25741353

  13. Distance Education: A Consumer's Guide. What Distance Learners Need To Know.

    ERIC Educational Resources Information Center

    Western Interstate Commission for Higher Education, Boulder, CO. Western Cooperative for Educational Communications.

    This pamphlet is intended to assist the consumer in making informed decisions when choosing between distance learning programs. Distance education and distance learners are defined. Included is advice on beginning a program search; choosing a school; accreditation; evaluating quality of electronically offered programs; evaluate non-accredited…

  14. Time delay and distance measurement

    NASA Technical Reports Server (NTRS)

    Abshire, James B. (Inventor); Sun, Xiaoli (Inventor)

    2011-01-01

    A method for measuring time delay and distance may include providing an electromagnetic radiation carrier frequency and modulating one or more of amplitude, phase, frequency, polarization, and pointing angle of the carrier frequency with a return to zero (RZ) pseudo random noise (PN) code. The RZ PN code may have a constant bit period and a pulse duration that is less than the bit period. A receiver may detect the electromagnetic radiation and calculate the scattering profile versus time (or range) by computing a cross correlation function between the recorded received signal and a three-state RZ PN code kernel in the receiver. The method also may be used for pulse delay time (i.e., PPM) communications.

  15. Do breeding phase and detection distance influence the effective area surveyed for northern goshawks?

    USGS Publications Warehouse

    Roberson, A.M.; Andersen, D.E.; Kennedy, P.L.

    2005-01-01

    Broadcast surveys using conspecific calls are currently the most effective method for detecting northern goshawks (Accipiter gentilis) during the breeding season. These surveys typically use alarm calls during the nestling phase and juvenile food-begging calls during the fledgling-dependency phase. Because goshawks are most vocal during the courtship phase, we hypothesized that this phase would be an effective time to detect goshawks. Our objective was to improve current survey methodology by evaluating the probability of detecting goshawks at active nests in northern Minnesota in 3 breeding phases and at 4 broadcast distances and to determine the effective area surveyed per broadcast station. Unlike previous studies, we broadcast calls at only 1 distance per trial. This approach better quantifies (1) the relationship between distance and probability of detection, and (2) the effective area surveyed (EAS) per broadcast station. We conducted 99 broadcast trials at 14 active breeding areas. When pooled over all distances, detection rates were highest during the courtship (70%) and fledgling-dependency phases (68%). Detection rates were lowest during the nestling phase (28%), when there appeared to be higher variation in likelihood of detecting individuals. EAS per broadcast station was 39.8 ha during courtship and 24.8 ha during fledgling-dependency. Consequently, in northern Minnesota, broadcast stations may be spaced 712m and 562 m apart when conducting systematic surveys during courtship and fledgling-dependency, respectively. We could not calculate EAS for the nestling phase because probability of detection was not a simple function of distance from nest. Calculation of EAS could be applied to other areas where the probability of detection is a known function of distance.

  16. The safe home project.

    PubMed

    Arphorn, Sara; Jiraniratisai, Sopaphan; Rungtakul, Rungsri; Phutta, Nikom

    2011-12-01

    The Thai Health Promotion Foundation supported the Improvement of Quality of Life of Informal Workers project in Ban Luang District, Amphur Photaram, Ratchaburi Province. There were many informal workers in Ban Luang District. Sweet-crispy fish producers in Ban Luang were the largest group among the sweet-crispy fish producers in Thailand. This project was aimed at improving living and working conditions of informal workers, with a focus on the sweet-crispy fish group. Good practices of improved living and working conditions were used to help informal workers build safe, healthy and productive work environments. These informal workers often worked in substandard conditions and were exposed to various hazards in the working area. These hazards included risk of exposure to hot work environment, ergonomics-related injuries, chemical hazards, electrical hazards etc. Ergonomics problems were commonly in the sweet-crispy fish group. Unnatural postures such as prolonged sitting were performed dominantly. One hundred and fifty informal workers participated in this project. Occupational health volunteers were selected to encourage occupational health and safety in four groups of informal workers in 2009. The occupational health volunteers trained in 2008 were farmers, beauty salon workers and doll makers. The occupational health and safety knowledge is extended to a new informal worker group: sweet-crispy fish producer, in 2009. The occupational health and safety training for sweet-crispy fish group is conducted by occupational health volunteers. The occupational health volunteers increased their skills and knowledge assist in to make safe home and safe community through participatory oriented training. The improvement of living and working condition is conducted by using a modified WISH, Work Improvement for Safe Home, checklist. The plans of improvement were recorded. The informal workers showed improvement mostly on material handling and storage. The safe uses and safe

  17. Weak form implementation of the semi-analytical finite element (SAFE) method for a variety of elastodynamic waveguides

    NASA Astrophysics Data System (ADS)

    Hakoda, Christopher; Lissenden, Clifford; Rose, Joseph L.

    2018-04-01

    Dispersion curves are essential to any guided wave NDE project. The Semi-Analytical Finite Element (SAFE) method has significantly increased the ease by which these curves can be calculated. However, due to misconceptions regarding theory and fragmentation based on different finite-element software, the theory has stagnated, and adoption by researchers who are new to the field has been slow. This paper focuses on the relationship between the SAFE formulation and finite element theory, and the implementation of the SAFE method in a weak form for plates, pipes, layered waveguides/composites, curved waveguides, and arbitrary cross-sections is shown. The benefits of the weak form are briefly described, as is implementation in open-source and commercial finite element software.

  18. Investigation on relationship between epicentral distance and growth curve of initial P-wave propagating in local heterogeneous media for earthquake early warning system

    NASA Astrophysics Data System (ADS)

    Okamoto, Kyosuke; Tsuno, Seiji

    2015-10-01

    In the earthquake early warning (EEW) system, the epicenter location and magnitude of earthquakes are estimated using the amplitude growth rate of initial P-waves. It has been empirically pointed out that the growth rate becomes smaller as epicentral distance becomes far regardless of the magnitude of earthquakes. So, the epicentral distance can be estimated from the growth rate using this empirical relationship. However, the growth rates calculated from different earthquakes at the same epicentral distance mark considerably different values from each other. Sometimes the growth rates of earthquakes having the same epicentral distance vary by 104 times. Qualitatively, it has been considered that the gap in the growth rates is due to differences in the local heterogeneities that the P-waves propagate through. In this study, we demonstrate theoretically how local heterogeneities in the subsurface disturb the relationship between the growth rate and the epicentral distance. Firstly, we calculate seismic scattered waves in a heterogeneous medium. First-ordered PP, PS, SP, and SS scatterings are considered. The correlation distance of the heterogeneities and fractional fluctuation of elastic parameters control the heterogeneous conditions for the calculation. From the synthesized waves, the growth rate of the initial P-wave is obtained. As a result, we find that a parameter (in this study, correlation distance) controlling heterogeneities plays a key role in the magnitude of the fluctuation of the growth rate. Then, we calculate the regional correlation distances in Japan that can account for the fluctuation of the growth rate of real earthquakes from 1997 to 2011 observed by K-NET and KiK-net. As a result, the spatial distribution of the correlation distance shows locality. So, it is revealed that the growth rates fluctuate according to the locality. When this local fluctuation is taken into account, the accuracy of the estimation of epicentral distances from initial P

  19. Evaluation of students' knowledge about paediatric dosage calculations.

    PubMed

    Özyazıcıoğlu, Nurcan; Aydın, Ayla İrem; Sürenler, Semra; Çinar, Hava Gökdere; Yılmaz, Dilek; Arkan, Burcu; Tunç, Gülseren Çıtak

    2018-01-01

    Medication errors are common and may jeopardize the patient safety. As paediatric dosages are calculated based on the child's age and weight, risk of error in dosage calculations is increasing. In paediatric patients, overdose drug prescribed regardless of the child's weight, age and clinical picture may lead to excessive toxicity and mortalities while low doses may delay the treatment. This study was carried out to evaluate the knowledge of nursing students about paediatric dosage calculations. This research, which is of retrospective type, covers a population consisting of all the 3rd grade students at the bachelor's degree in May, 2015 (148 students). Drug dose calculation questions in exam papers including 3 open ended questions on dosage calculation problems, addressing 5 variables were distributed to the students and their responses were evaluated by the researchers. In the evaluation of the data, figures and percentage distribution were calculated and Spearman correlation analysis was applied. Exam question on the dosage calculation based on child's age, which is the most common method in paediatrics, and which ensures right dosages and drug dilution was answered correctly by 87.1% of the students while 9.5% answered it wrong and 3.4% left it blank. 69.6% of the students was successful in finding the safe dose range, and 79.1% in finding the right ratio/proportion. 65.5% of the answers with regard to Ml/dzy calculation were correct. Moreover, student's four operation skills were assessed and 68.2% of the students were determined to have found the correct answer. When the relation among the questions on medication was examined, a significant relation (correlation) was determined between them. It is seen that in dosage calculations, the students failed mostly in calculating ml/dzy (decimal). This result means that as dosage calculations are based on decimal values, calculations may be ten times erroneous when the decimal point is placed wrongly. Moreover, it

  20. Research on Signature Verification Method Based on Discrete Fréchet Distance

    NASA Astrophysics Data System (ADS)

    Fang, J. L.; Wu, W.

    2018-05-01

    This paper proposes a multi-feature signature template based on discrete Fréchet distance, which breaks through the limitation of traditional signature authentication using a single signature feature. It solves the online handwritten signature authentication signature global feature template extraction calculation workload, signature feature selection unreasonable problem. In this experiment, the false recognition rate (FAR) and false rejection rate (FRR) of the statistical signature are calculated and the average equal error rate (AEER) is calculated. The feasibility of the combined template scheme is verified by comparing the average equal error rate of the combination template and the original template.

  1. Evidence that convergence rather than accommodation controls intermittent distance exotropia

    PubMed Central

    Horwood, Anna M; Riddell, Patricia M

    2015-01-01

    Purpose This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Methods 19 distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2m and 33cm. Stimulus and response AC/A and CA/C ratios were calculated. Results Accommodation responses for near targets (p=0.017) response gains (p=0.026) were greater in the exotropes than the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p=0.02), but significantly higher CA/C ratios (p=0.02). All the exotropes, whether the angle changed most with lenses (“controlled by accommodation”) or on occlusion (“controlled by fusion”), used binocular disparity not blur as their main cue to target distance. Conclusions Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting over-accommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. PMID:22280437

  2. Issues in access to safe drinking water and basic hygiene for persons with physical disabilities in rural Cambodia.

    PubMed

    MacLeod, Marin; Pann, Mala; Cantwell, Ray; Moore, Spencer

    2014-12-01

    An estimated 1.6 million people die from diarrheal diseases each year due to lack of access to safe water and sanitation, and persons with physical disabilities face additional barriers. In Cambodia, approximately 5% of the population is disabled, presenting substantial obstacles in accessing these basic services. The purpose of this study was twofold: first, to identify the challenges facing persons with physical disabilities in accessing safe household water and basic hygiene in rural Cambodia; and, second, to use these results to generate policy and practice recommendations for the water and sanitation hygiene sector implementing water treatment system interventions in rural settings. Fifteen field interviews were conducted with persons with physical disabilities. Thematic analysis was used to identify six main themes. The results indicated that environmental barriers to access were greater in the workplace than household settings and those persons with disabilities had greater awareness about safe drinking water compared to basic hygiene. Additionally, lack of physical strength, distance to water, and lack of financial means were noted as common access barriers. The findings support ongoing research and offer insight into the particular challenges facing persons with physical disabilities in rural areas in accessing safe drinking water and basic hygiene.

  3. Study of a fail-safe abort system for an actively cooled hypersonic aircraft: Computer program documentation

    NASA Technical Reports Server (NTRS)

    Haas, L. A., Sr.

    1976-01-01

    The Fail-Safe Abort System TEMPerature Analysis Program, (FASTEMP), user's manual is presented. This program was used to analyze fail-safe abort systems for an actively cooled hypersonic aircraft. FASTEMP analyzes the steady state or transient temperature response of a thermal model defined in rectangular, cylindrical, conical and/or spherical coordinate system. FASTEMP provides the user with a large selection of subroutines for heat transfer calculations. The various modes of heat transfer available from these subroutines are: heat storage, conduction, radiation, heat addition or generation, convection, and fluid flow.

  4. Biasing anisotropic scattering kernels for deep-penetration Monte Carlo calculations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carter, L.L.; Hendricks, J.S.

    1983-01-01

    The exponential transform is often used to improve the efficiency of deep-penetration Monte Carlo calculations. This technique is usually implemented by biasing the distance-to-collision kernel of the transport equation, but leaving the scattering kernel unchanged. Dwivedi obtained significant improvements in efficiency by biasing an isotropic scattering kernel as well as the distance-to-collision kernel. This idea is extended to anisotropic scattering, particularly the highly forward Klein-Nishina scattering of gamma rays.

  5. Average luminosity distance in inhomogeneous universes

    NASA Astrophysics Data System (ADS)

    Kostov, Valentin Angelov

    Using numerical ray tracing, the paper studies how the average distance modulus in an inhomogeneous universe differs from its homogeneous counterpart. The averaging is over all directions from a fixed observer not over all possible observers (cosmic), thus it is more directly applicable to our observations. Unlike previous studies, the averaging is exact, non-perturbative, an includes all possible non-linear effects. The inhomogeneous universes are represented by Sweese-cheese models containing random and simple cubic lattices of mass- compensated voids. The Earth observer is in the homogeneous cheese which has an Einstein - de Sitter metric. For the first time, the averaging is widened to include the supernovas inside the voids by assuming the probability for supernova emission from any comoving volume is proportional to the rest mass in it. For voids aligned in a certain direction, there is a cumulative gravitational lensing correction to the distance modulus that increases with redshift. That correction is present even for small voids and depends on the density contrast of the voids, not on their radius. Averaging over all directions destroys the cumulative correction even in a non-randomized simple cubic lattice of voids. Despite the well known argument for photon flux conservation, the average distance modulus correction at low redshifts is not zero due to the peculiar velocities. A formula for the maximum possible average correction as a function of redshift is derived and shown to be in excellent agreement with the numerical results. The formula applies to voids of any size that: (1) have approximately constant densities in their interior and walls, (2) are not in a deep nonlinear regime. The actual average correction calculated in random and simple cubic void lattices is severely damped below the predicted maximum. That is traced to cancelations between the corrections coming from the fronts and backs of different voids at the same redshift from the

  6. Measurement of distances between anatomical structures using a translating stage with mounted endoscope

    NASA Astrophysics Data System (ADS)

    Kahrs, Lueder A.; Blachon, Gregoire S.; Balachandran, Ramya; Fitzpatrick, J. Michael; Labadie, Robert F.

    2012-02-01

    During endoscopic procedures it is often desirable to determine the distance between anatomical features. One such clinical application is percutaneous cochlear implantation (PCI), which is a minimally invasive approach to the cochlea via a single, straight drill path and can be achieved accurately using bone-implanted markers and customized microstereotactic frame. During clinical studies to validate PCI, traditional open-field cochlear implant surgery was performed and prior to completion of the surgery, a customized microstereotactic frame designed to achieve the desired PCI trajectory was attached to the bone-implanted markers. To determine whether this trajectory would have safely achieved the target, a sham drill bit is passed through the frame to ensure that the drill bit would reach the cochlea without damaging vital structures. Because of limited access within the facial recess, the distances from the bit to anatomical features could not be measured with calipers. We hypothesized that an endoscope mounted on a sliding stage that translates only along the trajectory, would provide sufficient triangulation to accurately measure these distances. In this paper, the design, fabrication, and testing of such a system is described. The endoscope is mounted so that its optical axis is approximately aligned with the trajectory. Several images are acquired as the stage is moved, and threedimensional reconstruction of selected points allows determination of distances. This concept also has applicability in a large variety of rigid endoscopic interventions including bronchoscopy, laparoscopy, and sinus endoscopy.

  7. Comparison of calculation and simulation of evacuation in real buildings

    NASA Astrophysics Data System (ADS)

    Szénay, Martin; Lopušniak, Martin

    2018-03-01

    Each building must meet requirements for safe evacuation in order to prevent casualties. Therefore methods for evaluation of evacuation are used when designing buildings. In the paper, calculation methods were tested on three real buildings. The testing used methods of evacuation time calculation pursuant to Slovak standards and evacuation time calculation using the buildingExodus simulation software. If calculation methods have been suitably selected taking into account the nature of evacuation and at the same time if correct values of parameters were entered, we will be able to obtain almost identical times of evacuation in comparison with real results obtained from simulation. The difference can range from 1% to 27%.

  8. Possible linkage between neuronal recruitment and flight distance in migratory birds

    PubMed Central

    Barkan, Shay; Roll, Uri; Yom-Tov, Yoram; Wassenaar, Leonard I.; Barnea, Anat

    2016-01-01

    New neuronal recruitment in an adult animal’s brain is presumed to contribute to brain plasticity and increase the animal’s ability to contend with new and changing environments. During long-distance migration, birds migrating greater distances are exposed to more diverse spatial information. Thus, we hypothesized that greater migration distance in birds would correlate with the recruitment of new neurons into the brain regions involved with migratory navigation. We tested this hypothesis on two Palearctic migrants - reed warblers (Acrocephalus scirpaceus) and turtle doves (Streptopelia turtur), caught in Israel while returning from Africa in spring and summer. Birds were injected with a neuronal birth marker and later inspected for new neurons in brain regions known to play a role in navigation - the hippocampus and nidopallium caudolateral. We calculated the migration distance of each individual by matching feather isotopic values (δ2H and δ13C) to winter base-maps of these isotopes in Africa. Our findings suggest a positive correlation between migration distance and new neuronal recruitment in two brain regions - the hippocampus in reed warblers and nidopallium caudolateral in turtle doves. This multidisciplinary approach provides new insights into the ability of the avian brain to adapt to different migration challenges. PMID:26905978

  9. Measurement of Transcranial Distance During Head-Down Tilt Using Ultrasound

    NASA Technical Reports Server (NTRS)

    Torikoshi, Shigeyo; Ballard, R. E.; Watenpaugh, D. E.; Murthy, G.; Bowley, S.; Yost, W. T.; Hargens, Alan R.

    1995-01-01

    Exposure to microgravity probably elevates blood pressure and flow in the head which may increase intracranial volume (ICV) and pressure (ICP). Due to the slightly compliant nature of the cranium, any increase of ICP will increase ICV and transcranial distance. We used a noninvasive ultrasound technique to measure transcranial distance (frontal to occipital) during head-down tilt. Seven subjects (ages 26-53) underwent the following tilt angles: 90 deg. upright, 30 deg., 0 deg., -6 deg., -10 deg., -6 deg., 0 deg., 30 deg., and 90 deg. Each angle was maintained for 1 min. Ultrasound wave frequency was collected continuously and transcranial distance was calculated (Delta(x) = x(Delta)f/f, where x is path length and f is frequency of the wave) for each tilt angle. Frequency decreased from 503.687 kHz (90 deg. upright) to 502.619 kHz (-10 deg.). These frequencies translated to an increased transcranial distance of 0.403 mm. Although our data suggest a significant increase in transcranial distance during head-down tilt, this apparent increase may result, in part, from head-down tilt-induced subcutaneous edema or cutaneous blood volume elevation. In three subjects, when the above protocol was repeated with an ace bandage wrapped around the head to minimize such edema, the increased transcranial distance from 90 deg. to -10 deg. was reduced by 0.174 mm. Further development of the technique to quantify bone-to-bone expansion unconfounded by cutaneous fluid is necessary. Therefore, this ultrasound technique may provide measurements of changes in cranial dimensions during microgravity.

  10. The effect of uncertainties in distance-based ranking methods for multi-criteria decision making

    NASA Astrophysics Data System (ADS)

    Jaini, Nor I.; Utyuzhnikov, Sergei V.

    2017-08-01

    Data in the multi-criteria decision making are often imprecise and changeable. Therefore, it is important to carry out sensitivity analysis test for the multi-criteria decision making problem. The paper aims to present a sensitivity analysis for some ranking techniques based on the distance measures in multi-criteria decision making. Two types of uncertainties are considered for the sensitivity analysis test. The first uncertainty is related to the input data, while the second uncertainty is towards the Decision Maker preferences (weights). The ranking techniques considered in this study are TOPSIS, the relative distance and trade-off ranking methods. TOPSIS and the relative distance method measure a distance from an alternative to the ideal and antiideal solutions. In turn, the trade-off ranking calculates a distance of an alternative to the extreme solutions and other alternatives. Several test cases are considered to study the performance of each ranking technique in both types of uncertainties.

  11. Safe Local Navigation for Visually Impaired Users With a Time-of-Flight and Haptic Feedback Device.

    PubMed

    Katzschmann, Robert K; Araki, Brandon; Rus, Daniela

    2018-03-01

    This paper presents ALVU (Array of Lidars and Vibrotactile Units), a contactless, intuitive, hands-free, and discreet wearable device that allows visually impaired users to detect low- and high-hanging obstacles, as well as physical boundaries in their immediate environment. The solution allows for safe local navigation in both confined and open spaces by enabling the user to distinguish free space from obstacles. The device presented is composed of two parts: a sensor belt and a haptic strap. The sensor belt is an array of time-of-flight distance sensors worn around the front of a user's waist, and the pulses of infrared light provide reliable and accurate measurements of the distances between the user and surrounding obstacles or surfaces. The haptic strap communicates the measured distances through an array of vibratory motors worn around the user's upper abdomen, providing haptic feedback. The linear vibration motors are combined with a point-loaded pretensioned applicator to transmit isolated vibrations to the user. We validated the device's capability in an extensive user study entailing 162 trials with 12 blind users. Users wearing the device successfully walked through hallways, avoided obstacles, and detected staircases.

  12. How Safe Are Kid-Safe Search Engines?

    ERIC Educational Resources Information Center

    Masterson-Krum, Hope

    2001-01-01

    Examines search tools available to elementary and secondary school students, both human-compiled and crawler-based, to help direct them to age-appropriate Web sites; analyzes the procedures of search engines labeled family-friendly or kid safe that use filters; and tests the effectiveness of these services to students in school libraries. (LRW)

  13. Safe zones and a technical guide for cerclage wiring of the femur: a computed topographic angiogram (CTA) study.

    PubMed

    Apivatthakakul, Theerachai; Siripipattanamongkol, P; Oh, Chang-Wug; Sananpanich, K; Phornphutkul, C

    2018-01-01

    Cerclage wiring for reduction of complex femoral shaft fractures can create iatrogenic vascular injury. To describe the anatomical relation of blood vessels to the femur and develop a technical guide for safe passage of cerclage wire. CT lower-limb angiographs (CTA) of 80 patients were reviewed and analysed to identify the superficial femoral artery (SFA) and the deep femoral artery (DFA) as well as the relation of those arteries to the femoral cortex. The total length of the femur was measured and divided into eight equal segments (seven levels). At each level, the medial half of the femur was divided into eight sectors labelled A through H and the position of the SFA and DFA was recorded. The shortest distance between the femoral cortex and the SFA and DFA at each level was measured. The data was analysed using STATA version 10.0. The average total femoral length from the tip of greater trochanter to lateral joint line was 402.98 ± 26.16 cm. The average distances from the SFA to the femur (d1) for levels 1 through 7 were 37.20 ± 5.0, 32.09 ± 4.74, 27.13 ± 4.19, 27.71 ± 5.46, 23.71 ± 4.40, 13.63 ± 3.59 and 10.08 ± 3.09 mm, respectively. The average distances between the DFA and the femur (d2) for levels 1 through 3 were 26.70 ± 4.13, 14.76 ± 3.27 and 9.58 ± 3.79 mm, respectively. The position of the SFA is located in sectors B through E at levels 1-3 and in sectors E through H at levels 4-7 and the position of the DFA located in sectors B through F at levels 1-3. Cerclage wiring should be started from the posterior intermuscular septum at the linea aspera. The safe area is the proximal half (midshaft) of the femur where the SFA and DFA lie at a safe distance from the femur. Between the midshaft and the distal 1/4, insertion of the passer must be done meticulously with the tip kept close to posteromedial cortex. Below the distal 1/4, the tip of the passer should be kept close to the posterior cortex to avoid injury to the SFA and

  14. Distance Determination by Gated Viewing Systems Taking into Account the Illuminating Pulse Shape

    NASA Astrophysics Data System (ADS)

    Gorobets, V. A.; Kuntsevich, B. F.; Shabrov, D. V.

    2017-11-01

    For gated viewing systems with triangular and trapezoidal illuminating pulses, we have obtained the range-intensity profiles (RIPs) of the signal as the time delay was varied between the leading edges of the gate pulse and the illuminating pulse. We have established that if the duration of the illuminating pulse Δtlas is less than or equal to the duration of the gate pulse ΔtIC, then the expressions for the characteristic distances are the same as for rectangular pulses and they can be used to determine the distance to objects. When Δtlas > ΔtIC, in the case of triangular illuminating pulses the RIP is bell-shaped. For trapezoidal pulses, the RIP is bell-shaped with or without a plateau section. We propose an empirical method for determining the characteristic distances to the RIP maximum and the boundary points for the plateau section, which we then use to calculate the distance to the object. Using calibration constants, we propose a method for determining the distance to an object and we have experimentally confirmed the feasibility of this method.

  15. SOME PROBLEMS OF "SAFE DOSE" ESTIMATION

    EPA Science Inventory

    In environmental carcinogenic risk assessment, the usually defined "safe doses" appear subjective in some sense. n this paper a method of standardizing "safe doses" based on some objective parameters is introduced and a procedure of estimating safe doses under the competing risks...

  16. Benchmarking Distance Control and Virtual Drilling for Lateral Skull Base Surgery.

    PubMed

    Voormolen, Eduard H J; Diederen, Sander; van Stralen, Marijn; Woerdeman, Peter A; Noordmans, Herke Jan; Viergever, Max A; Regli, Luca; Robe, Pierre A; Berkelbach van der Sprenkel, Jan Willem

    2018-01-01

    Novel audiovisual feedback methods were developed to improve image guidance during skull base surgery by providing audiovisual warnings when the drill tip enters a protective perimeter set at a distance around anatomic structures ("distance control") and visualizing bone drilling ("virtual drilling"). To benchmark the drill damage risk reduction provided by distance control, to quantify the accuracy of virtual drilling, and to investigate whether the proposed feedback methods are clinically feasible. In a simulated surgical scenario using human cadavers, 12 unexperienced users (medical students) drilled 12 mastoidectomies. Users were divided into a control group using standard image guidance and 3 groups using distance control with protective perimeters of 1, 2, or 3 mm. Damage to critical structures (sigmoid sinus, semicircular canals, facial nerve) was assessed. Neurosurgeons performed another 6 mastoidectomy/trans-labyrinthine and retro-labyrinthine approaches. Virtual errors as compared with real postoperative drill cavities were calculated. In a clinical setting, 3 patients received lateral skull base surgery with the proposed feedback methods. Users drilling with distance control protective perimeters of 3 mm did not damage structures, whereas the groups using smaller protective perimeters and the control group injured structures. Virtual drilling maximum cavity underestimations and overestimations were 2.8 ± 0.1 and 3.3 ± 0.4 mm, respectively. Feedback methods functioned properly in the clinical setting. Distance control reduced the risks of drill damage proportional to the protective perimeter distance. Errors in virtual drilling reflect spatial errors of the image guidance system. These feedback methods are clinically feasible. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Understanding the tissue interaction of new treatment modalities in laparoscopic surgery in view of safe and effective application (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Grimbergen, Matthijs C. M.; Klaessens, John H.; van der Veen, Albert J.; Verdaasdonk, Rudolf M.

    2016-03-01

    During laparoscopic surgery, devices are require to either cut, ablate or coagulate tissue and veins with high precision and controlled lateral damage preferably in an one-for-all modality. The tissue interactions of 3 new treatment modalities were studied using special imaging techniques to obtain a better understanding the working mechanism in view of effective and safe application. The Plasmajet produces a high temperature ionized gas 'flame' directed to the tissue surface at the tip of a 4 mm diameter rigid hand piece. The Lumenis DUO CO2 laser enables endoscopic laser energy delivery through a 1 mm outer diameter flexible hollow waveguide. The 2 µm 'Thulium' laser is delivered by (standard) 400 µm diameter optical fiber. Thermal imaging and Schlieren techniques were used to assess the superficial ablative and coagulation effects these surgical instruments scanning at preset velocities and distances from the surface of biological tissues and phantoms . The CO2 was very effective in tissue ablation even at a distance up to 10 mm due to a very small diverging beam from the hollow waveguide. In contrast, the Thulium laser showed less ablation and increasing coagulation at larger distance to the tissue. The gas 'flame' of the Plasmajet spread the thermal energy over the surface for effective superficial ablation and coagulation. However, the pressure of the gas flow is substantial on the tissue surface creating turbulence and even indirect cooling. The specific ablation and coagulation effects of the three treatment modalities have to be appreciate and the effective and safe application will depend on the preference and skills of the surgeon

  18. Potential, velocity, and density fields from sparse and noisy redshift-distance samples - Method

    NASA Technical Reports Server (NTRS)

    Dekel, Avishai; Bertschinger, Edmund; Faber, Sandra M.

    1990-01-01

    A method for recovering the three-dimensional potential, velocity, and density fields from large-scale redshift-distance samples is described. Galaxies are taken as tracers of the velocity field, not of the mass. The density field and the initial conditions are calculated using an iterative procedure that applies the no-vorticity assumption at an initial time and uses the Zel'dovich approximation to relate initial and final positions of particles on a grid. The method is tested using a cosmological N-body simulation 'observed' at the positions of real galaxies in a redshift-distance sample, taking into account their distance measurement errors. Malmquist bias and other systematic and statistical errors are extensively explored using both analytical techniques and Monte Carlo simulations.

  19. Progress in calculating the potential energy surface of H3+.

    PubMed

    Adamowicz, Ludwik; Pavanello, Michele

    2012-11-13

    The most accurate electronic structure calculations are performed using wave function expansions in terms of basis functions explicitly dependent on the inter-electron distances. In our recent work, we use such basis functions to calculate a highly accurate potential energy surface (PES) for the H(3)(+) ion. The functions are explicitly correlated Gaussians, which include inter-electron distances in the exponent. Key to obtaining the high accuracy in the calculations has been the use of the analytical energy gradient determined with respect to the Gaussian exponential parameters in the minimization of the Rayleigh-Ritz variational energy functional. The effective elimination of linear dependences between the basis functions and the automatic adjustment of the positions of the Gaussian centres to the changing molecular geometry of the system are the keys to the success of the computational procedure. After adiabatic and relativistic corrections are added to the PES and with an effective accounting of the non-adiabatic effects in the calculation of the rotational/vibrational states, the experimental H(3)(+) rovibrational spectrum is reproduced at the 0.1 cm(-1) accuracy level up to 16,600 cm(-1) above the ground state.

  20. Evidence that convergence rather than accommodation controls intermittent distance exotropia.

    PubMed

    Horwood, Anna M; Riddell, Patricia M

    2012-03-01

    This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Nineteen distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2 m and 33 cm. Stimulus and response AC/A and CA/C ratios were calculated. Accommodation responses for near targets (p = 0.017) and response gains (p = 0.026) were greater in the exotropes than in the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p = 0.02), but significantly higher CA/C ratios (p = 0.02). All the exotropes, whether the angle changed most with lenses ('controlled by accommodation') or on occlusion ('controlled by fusion'), used binocular disparity not blur as their main cue to target distance. Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting overaccommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

  1. Using Opioids Safely After Surgery

    MedlinePlus

    ... Adult , Geriatric Using Opioids Safely After Surgery Using Opioids Safely After Surgery Stick to the lowest dose ... need opioid pain medicine. If your doctor says opioids aren’t necessary. If your doctor thinks you ...

  2. How Safe Is Safe Enough for Self-Driving Vehicles?

    PubMed

    Liu, Peng; Yang, Run; Xu, Zhigang

    2018-05-21

    Self-driving vehicles (SDVs) promise to considerably reduce traffic crashes. One pressing concern facing the public, automakers, and governments is "How safe is safe enough for SDVs?" To answer this question, a new expressed-preference approach was proposed for the first time to determine the socially acceptable risk of SDVs. In our between-subject survey (N = 499), we determined the respondents' risk-acceptance rate of scenarios with varying traffic-risk frequencies to examine the logarithmic relationships between the traffic-risk frequency and risk-acceptance rate. Logarithmic regression models of SDVs were compared to those of human-driven vehicles (HDVs); the results showed that SDVs were required to be safer than HDVs. Given the same traffic-risk-acceptance rates for SDVs and HDVs, their associated acceptable risk frequencies of SDVs and HDVs were predicted and compared. Two risk-acceptance criteria emerged: the tolerable risk criterion, which indicates that SDVs should be four to five times as safe as HDVs, and the broadly acceptable risk criterion, which suggests that half of the respondents hoped that the traffic risk of SDVs would be two orders of magnitude lower than the current estimated traffic risk. The approach and these results could provide insights for government regulatory authorities for establishing clear safety requirements for SDVs. © 2018 Society for Risk Analysis.

  3. Point kernel calculations of skyshine exposure rates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roseberry, M.L.; Shultis, J.K.

    1982-02-01

    A simple point kernel model is presented for the calculation of skyshine exposure rates arising from the atmospheric reflection of gamma radiation produced by a vertically collimated or a shielded point source. This model is shown to be in good agreement with benchmark experimental data from a /sup 60/Co source for distances out to 700 m.

  4. Genome-wide gene order distances support clustering the gram-positive bacteria

    PubMed Central

    House, Christopher H.; Pellegrini, Matteo; Fitz-Gibbon, Sorel T.

    2015-01-01

    Initially using 143 genomes, we developed a method for calculating the pair-wise distance between prokaryotic genomes using a Monte Carlo method to estimate the conservation of gene order. The method was based on repeatedly selecting five or six non-adjacent random orthologs from each of two genomes and determining if the chosen orthologs were in the same order. The raw distances were then corrected for gene order convergence using an adaptation of the Jukes-Cantor model, as well as using the common distance correction D′ = −ln(1-D). First, we compared the distances found via the order of six orthologs to distances found based on ortholog gene content and small subunit rRNA sequences. The Jukes-Cantor gene order distances are reasonably well correlated with the divergence of rRNA (R2 = 0.24), especially at rRNA Jukes-Cantor distances of less than 0.2 (R2 = 0.52). Gene content is only weakly correlated with rRNA divergence (R2 = 0.04) over all distances, however, it is especially strongly correlated at rRNA Jukes-Cantor distances of less than 0.1 (R2 = 0.67). This initial work suggests that gene order may be useful in conjunction with other methods to help understand the relatedness of genomes. Using the gene order distances in 143 genomes, the relations of prokaryotes were studied using neighbor joining and agreement subtrees. We then repeated our study of the relations of prokaryotes using gene order in 172 complete genomes better representing a wider-diversity of prokaryotes. Consistently, our trees show the Actinobacteria as a sister group to the bulk of the Firmicutes. In fact, the robustness of gene order support was found to be considerably greater for uniting these two phyla than for uniting any of the proteobacterial classes together. The results are supportive of the idea that Actinobacteria and Firmicutes are closely related, which in turn implies a single origin for the gram-positive cell. PMID:25653643

  5. Effect of oxygen impurities on properties of the ternary superconductor SnMo/sub 6/S/sub 8/: Extended x-ray-absorption fine-structure determination of bond distances and local-density cluster calculations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guenzburger, D.; Ellis, D.E.; Montano, P.A.

    1985-10-01

    Electronic structure calculations were performed for clusters representing the Chevrel-phase SnMo/sub 6/S/sub 8/, with and without oxygen doping. In order to obtain the local structure around the Sn atom, extended x-ray-absorption fine-structure (EXAFS) measurements were made with synchro- tron radiation. The interatomic distances obtained experimentally were used in the calculations. The effect of oxygen doping on the Moessbauer isomer shift and quadrupole splitting values of /sup 119/Sn was investigated theoretically and compared with reported experimental values. The effect of oxygen substitution on the density of states at the Fermi energy of the (Mo/sub 6/S/sub 8/)/sup 2 -/ cluster was alsomore » studied. The results suggest that oxygen doping does not alter significantly the electronic structure of SnMo/sub 6/S/sub 8/.« less

  6. Lifelong Learning & Distance Higher Education. Perspectives on Distance Education

    ERIC Educational Resources Information Center

    McIntosh, Christopher, Ed.

    2005-01-01

    Reflecting a common objective of ensuring quality Education for All, this book is a joint initiative of UNESCO and COL and jointly published. Lifelong Learning in Distance Higher Education brings together a diverse group of experts from many countries. The book provides a clear picture of the challenges, problems and potential of distance higher…

  7. Double quantum coherence ESR spectroscopy and quantum chemical calculations on a BDPA biradical.

    PubMed

    Haeri, Haleh Hashemi; Spindler, Philipp; Plackmeyer, Jörn; Prisner, Thomas

    2016-10-26

    Carbon-centered radicals are interesting alternatives to otherwise commonly used nitroxide spin labels for dipolar spectroscopy techniques because of their narrow ESR linewidth. Herein, we present a novel BDPA biradical, where two BDPA (α,α,γ,γ-bisdiphenylene-β-phenylallyl) radicals are covalently tethered by a saturated biphenyl acetylene linker. The inter-spin distance between the two spin carrier fragments was measured using double quantum coherence (DQC) ESR methodology. The DQC experiment revealed a mean distance of only 1.8 nm between the two unpaired electron spins. This distance is shorter than the predictions based on a simple modelling of the biradical geometry with the electron spins located at the central carbon atoms. Therefore, DFT (density functional theory) calculations were performed to obtain a picture of the spin delocalization, which may give rise to a modified dipolar interaction tensor, and to find those conformations that correspond best to the experimentally observed inter-spin distance. Quantum chemical calculations showed that the attachment of the biphenyl acetylene linker at the second position of the fluorenyl ring of BDPA did not affect the spin population or geometry of the BDPA radical. Therefore, spin delocalization and geometry optimization of each BDPA moiety could be performed on the monomeric unit alone. The allylic dihedral angle θ 1 between the fluorenyl rings in the monomer subunit was determined to be 30° or 150° using quantum chemical calculations. The proton hyperfine coupling constant calculated from both energy minima was in very good agreement with literature values. Based on the optimal monomer geometries and spin density distributions, the dipolar coupling interaction between both BDPA units could be calculated for several dimer geometries. It was shown that the rotation of the BDPA units around the linker axis (θ 2 ) does not significantly influence the dipolar coupling strength when compared to the allylic

  8. Topological Distances Between Brain Networks

    PubMed Central

    Lee, Hyekyoung; Solo, Victor; Davidson, Richard J.; Pollak, Seth D.

    2018-01-01

    Many existing brain network distances are based on matrix norms. The element-wise differences may fail to capture underlying topological differences. Further, matrix norms are sensitive to outliers. A few extreme edge weights may severely affect the distance. Thus it is necessary to develop network distances that recognize topology. In this paper, we introduce Gromov-Hausdorff (GH) and Kolmogorov-Smirnov (KS) distances. GH-distance is often used in persistent homology based brain network models. The superior performance of KS-distance is contrasted against matrix norms and GH-distance in random network simulations with the ground truths. The KS-distance is then applied in characterizing the multimodal MRI and DTI study of maltreated children.

  9. Semantic distance as a critical factor in icon design for in-car infotainment systems.

    PubMed

    Silvennoinen, Johanna M; Kujala, Tuomo; Jokinen, Jussi P P

    2017-11-01

    In-car infotainment systems require icons that enable fluent cognitive information processing and safe interaction while driving. An important issue is how to find an optimised set of icons for different functions in terms of semantic distance. In an optimised icon set, every icon needs to be semantically as close as possible to the function it visually represents and semantically as far as possible from the other functions represented concurrently. In three experiments (N = 21 each), semantic distances of 19 icons to four menu functions were studied with preference rankings, verbal protocols, and the primed product comparisons method. The results show that the primed product comparisons method can be efficiently utilised for finding an optimised set of icons for time-critical applications out of a larger set of icons. The findings indicate the benefits of the novel methodological perspective into the icon design for safety-critical contexts in general. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. The Cost of Distance Education. IEC Broadsheets on Distance Learning No. 17.

    ERIC Educational Resources Information Center

    Perraton, Hilary

    One of a series offering practical advice and information on distance teaching, this broadsheet first looks at the reasons for trying to measure distance teaching costs and the methodological and economic difficulties involved in such measurements. Broadcasting and print costs in distance teaching are discussed, and evidence about the costs of…

  11. How to Safely Give Acetaminophen

    MedlinePlus

    ... Educators Search English Español How to Safely Give Acetaminophen KidsHealth / For Parents / How to Safely Give Acetaminophen ... without getting a doctor's OK first. What Is Acetaminophen Also Called? Acetaminophen is the generic name of ...

  12. Distancing from experienced self: how global-versus-local perception affects estimation of psychological distance.

    PubMed

    Liberman, Nira; Förster, Jens

    2009-08-01

    In 4 studies, the authors examined the prediction derived from construal level theory (CLT) that higher level of perceptual construal would enhance estimated egocentric psychological distance. The authors primed participants with global perception, local perception, or both (the control condition). Relative to the control condition, global processing made participants estimate larger psychological distances in time (Study 1), space (Study 2), social distance (Study 3), and hypotheticality (Study 4). Local processing had the opposite effect. Consistent with CLT, all studies show that the effect of global-versus-local processing did emerge when participants estimated egocentric distances, which are distances from the experienced self in the here and now, but did not emerge with temporal distances not from now (Study 1), spatial distances not from here (Study 2), social distances not from the self (Study 3), or hypothetical events that did not involve altering an experienced reality (Study 4).

  13. Distance learning perspectives.

    PubMed

    Pandza, Haris; Masic, Izet

    2013-01-01

    The development of modern technology and the Internet has enabled the explosive growth of distance learning. distance learning is a process that is increasingly present in the world. This is the field of education focused on educating students who are not physically present in the traditional classrooms or student's campus. described as a process where the source of information is separated from the students in space and time. If there are situations that require the physical presence of students, such as when a student is required to physically attend the exam, this is called a hybrid form of distance learning. This technology is increasingly used worldwide. The Internet has become the main communication channel for the development of distance learning.

  14. Backscattering measurement of 6He on 209Bi: Critical interaction distance

    NASA Astrophysics Data System (ADS)

    Guimarães, V.; Kolata, J. J.; Aguilera, E. F.; Howard, A.; Roberts, A.; Becchetti, F. D.; Torres-Isea, R. O.; Riggins, A.; Febrarro, M.; Scarduelli, V.; de Faria, P. N.; Monteiro, D. S.; Huiza, J. F. P.; Arazi, A.; Hinnefeld, J.; Moro, A. M.; Rossi, E. S.; Morcelle, V.; Barioni, A.

    2016-06-01

    An elastic backscattering experiment has been performed at energies below the Coulomb barrier to investigate static and dynamic effects in the interaction of 6He with 209Bi. The measured cross sections are presented in terms of the d σ /d σR u t h ratio, as a function of the distance of closest approach on a Rutherford trajectory. The data are compared with a three-body CDCC calculation and good agreement is observed. In addition, the critical distance of interaction was extracted. A larger value was obtained for the exotic 6He nucleus as compared with the weakly bound 6Li and 9Be nuclei and the tightly bound 4He12C, and 16O nuclei.

  15. Dispersion Distance and the Matter Distribution of the Universe in Dispersion Space.

    PubMed

    Masui, Kiyoshi Wesley; Sigurdson, Kris

    2015-09-18

    We propose that "standard pings," brief broadband radio impulses, can be used to study the three-dimensional clustering of matter in the Universe even in the absence of redshift information. The dispersion of radio waves as they travel through the intervening plasma can, like redshift, be used as a cosmological distance measure. Because of inhomogeneities in the electron density along the line of sight, dispersion is an imperfect proxy for radial distance and we show that this leads to calculable dispersion-space distortions in the apparent clustering of sources. Fast radio bursts (FRBs) are a new class of radio transients that are the prototypical standard ping and, due to their high observed dispersion, have been interpreted as originating at cosmological distances. The rate of fast radio bursts has been estimated to be several thousand over the whole sky per day and, if cosmological, the sources of these events should trace the large-scale structure of the Universe. We calculate the dispersion-space power spectra for a simple model where electrons and FRBs are biased tracers of the large-scale structure of the Universe, and we show that the clustering signal could be measured using as few as 10 000 events. Such a survey is in line with what may be achieved with upcoming wide-field radio telescopes.

  16. Dispersion Distance and the Matter Distribution of the Universe in Dispersion Space

    NASA Astrophysics Data System (ADS)

    Masui, Kiyoshi Wesley; Sigurdson, Kris

    2015-09-01

    We propose that "standard pings," brief broadband radio impulses, can be used to study the three-dimensional clustering of matter in the Universe even in the absence of redshift information. The dispersion of radio waves as they travel through the intervening plasma can, like redshift, be used as a cosmological distance measure. Because of inhomogeneities in the electron density along the line of sight, dispersion is an imperfect proxy for radial distance and we show that this leads to calculable dispersion-space distortions in the apparent clustering of sources. Fast radio bursts (FRBs) are a new class of radio transients that are the prototypical standard ping and, due to their high observed dispersion, have been interpreted as originating at cosmological distances. The rate of fast radio bursts has been estimated to be several thousand over the whole sky per day and, if cosmological, the sources of these events should trace the large-scale structure of the Universe. We calculate the dispersion-space power spectra for a simple model where electrons and FRBs are biased tracers of the large-scale structure of the Universe, and we show that the clustering signal could be measured using as few as 10 000 events. Such a survey is in line with what may be achieved with upcoming wide-field radio telescopes.

  17. Web-Based Communications, the Internet, and Distance Education. Readings in Distance Education, Number 7.

    ERIC Educational Resources Information Center

    Moore, Michael G., Ed.; Cozine, Geoffrey T., Ed.

    This book brings together a selection of articles published in "The American Journal of Distance Education" that are related to Web-based delivery of distance education. Articles include: "Performance and Perceptions of Distance Learners in Cyberspace" (Peter Navarro and Judy Shoemaker); "Distance Education for Dentists: Improving the Quality of…

  18. Has Distance Learning Become More Flexible? Reflections of a Distance Learning Student

    ERIC Educational Resources Information Center

    Thomas, Theda

    2012-01-01

    This paper provides insight into the way in which distance learning had changed over the past 30 years from the perspective of the author as a distance learning student. The question is then asked as to whether current practice is reducing flexibility for distance learning students? The paper starts with a discussion of flexible learning and the…

  19. InaSAFE applications in disaster preparedness

    NASA Astrophysics Data System (ADS)

    Pranantyo, Ignatius Ryan; Fadmastuti, Mahardika; Chandra, Fredy

    2015-04-01

    Disaster preparedness activities aim to reduce the impact of disasters by being better prepared to respond when a disaster occurs. In order to better anticipate requirements during a disaster, contingency planning activities can be undertaken prior to a disaster based on a realistic disaster scenario. InaSAFE is a tool that can inform this process. InaSAFE is a free and open source software that estimates the impact to people and infrastructure from potential hazard scenarios. By using InaSAFE, disaster managers can develop scenarios of disaster impacts (people and infrastructures affected) to inform their contingency plan and emergency response operation plan. While InaSAFE provides the software framework exposure data and hazard data are needed as inputs to run this software. Then InaSAFE can be used to forecast the impact of the hazard scenario to the exposure data. InaSAFE outputs include estimates of the number of people, buildings and roads are affected, list of minimum needs (rice and clean water), and response checklist. InaSAFE is developed by Indonesia's National Disaster Management Agency (BNPB) and the Australian Government, through the Australia-Indonesia Facility for Disaster Reduction (AIFDR), in partnership with the World Bank - Global Facility for Disaster Reduction and Recovery (GFDRR). This software has been used in many parts of Indonesia, including Padang, Maumere, Jakarta, and Slamet Mountain for emergency response and contingency planning.

  20. Oscillation properties of active and sterile neutrinos and neutrino anomalies at short distances

    NASA Astrophysics Data System (ADS)

    Khruschov, V. V.; Fomichev, S. V.; Titov, O. A.

    2016-09-01

    A generalized phenomenological (3 + 2 + 1) model featuring three active and three sterile neutrinos that is intended for calculating oscillation properties of neutrinos for the case of a normal activeneutrino mass hierarchy and a large splitting between the mass of one sterile neutrino and the masses of the other two sterile neutrinos is considered. A new parametrization and a specific form of the general mixing matrix are proposed for active and sterile neutrinos with allowance for possible CP violation in the lepton sector, and test values are chosen for the neutrino masses and mixing parameters. The probabilities for the transitions between different neutrino flavors are calculated, and graphs representing the probabilities for the disappearance of muon neutrinos/antineutrinos and the appearance of electron neutrinos/antineutrinos in a beam of muon neutrinos/antineutrinos versus the distance from the neutrino source for various values of admissible model parameters at neutrino energies not higher than 50 MeV, as well as versus the ratio of this distance to the neutrino energy, are plotted. It is shown that the short-distance accelerator anomaly in neutrino data (LNSD anomaly) can be explained in the case of a specific mixing matrix for active and sterile neutrinos (which belongs to the a 2 type) at the chosen parameter values. The same applies to the short-distance reactor and gallium anomalies. The theoretical results obtained in the present study can be used to interpret and predict the results of ground-based neutrino experiments aimed at searches for sterile neutrinos, as well as to analyze some astrophysical observational data.

  1. A revised moving cluster distance to the Pleiades open cluster

    NASA Astrophysics Data System (ADS)

    Galli, P. A. B.; Moraux, E.; Bouy, H.; Bouvier, J.; Olivares, J.; Teixeira, R.

    2017-02-01

    Context. The distance to the Pleiades open cluster has been extensively debated in the literature over several decades. Although different methods point to a discrepancy in the trigonometric parallaxes produced by the Hipparcos mission, the number of individual stars with known distances is still small compared to the number of cluster members to help solve this problem. Aims: We provide a new distance estimate for the Pleiades based on the moving cluster method, which will be useful to further discuss the so-called Pleiades distance controversy and compare it with the very precise parallaxes from the Gaia space mission. Methods: We apply a refurbished implementation of the convergent point search method to an updated census of Pleiades stars to calculate the convergent point position of the cluster from stellar proper motions. Then, we derive individual parallaxes for 64 cluster members using radial velocities compiled from the literature, and approximate parallaxes for another 1146 stars based on the spatial velocity of the cluster. This represents the largest sample of Pleiades stars with individual distances to date. Results: The parallaxes derived in this work are in good agreement with previous results obtained in different studies (excluding Hipparcos) for individual stars in the cluster. We report a mean parallax of 7.44 ± 0.08 mas and distance of pc that is consistent with the weighted mean of 135.0 ± 0.6 pc obtained from the non-Hipparcos results in the literature. Conclusions: Our result for the distance to the Pleiades open cluster is not consistent with the Hipparcos catalog, but favors the recent and more precise distance determination of 136.2 ± 1.2 pc obtained from Very Long Baseline Interferometry observations. It is also in good agreement with the mean distance of 133 ± 5 pc obtained from the first trigonometric parallaxes delivered by the Gaia satellite for the brightest cluster members in common with our sample. Full Table B.2 is only

  2. Misinterpretation of statistical distance in security of quantum key distribution shown by simulation

    NASA Astrophysics Data System (ADS)

    Iwakoshi, Takehisa; Hirota, Osamu

    2014-10-01

    This study will test an interpretation in quantum key distribution (QKD) that trace distance between the distributed quantum state and the ideal mixed state is a maximum failure probability of the protocol. Around 2004, this interpretation was proposed and standardized to satisfy both of the key uniformity in the context of universal composability and operational meaning of the failure probability of the key extraction. However, this proposal has not been verified concretely yet for many years while H. P. Yuen and O. Hirota have thrown doubt on this interpretation since 2009. To ascertain this interpretation, a physical random number generator was employed to evaluate key uniformity in QKD. In this way, we calculated statistical distance which correspond to trace distance in quantum theory after a quantum measurement is done, then we compared it with the failure probability whether universal composability was obtained. As a result, the degree of statistical distance of the probability distribution of the physical random numbers and the ideal uniformity was very large. It is also explained why trace distance is not suitable to guarantee the security in QKD from the view point of quantum binary decision theory.

  3. Strategies for Countering Terrorist Safe Havens

    DTIC Science & Technology

    2014-02-20

    within safe havens, tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case studies to...leadership targeting within safe havens, tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case ...surrogate forces and pseudo operations—provide viable potential options for USSOF to counter the complex problem of safe havens. Overall, the case

  4. Location of the Common Peroneal Nerve in Valgus Knees-Is the Reported Safe Zone for Well-Aligned Knees Applicable?

    PubMed

    Yang, Dejin; Shao, Hongyi; Zhou, Yixin; Tang, Hao; Guo, Shengjie

    2017-11-01

    Lateral soft-tissue release can jeopardize the common peroneal nerve (CPN) in total knee arthroplasty for valgus knees. Previous studies reporting safe zones to protect the CPN were based on well-aligned knees. We conducted this study to compare the localization of the CPN in well-aligned knees and in valgus knees. We conducted a consecutive 3-dimensional radiographic study on magnetic resonance images of 58 well-aligned knees and 39 valgus knees. We measured the distance between the CPN and the tibia, as well as the mediolateral, anteroposterior, and angular location of the CPN. We compared the results between well-aligned knees and valgus knees. We found that there is an increased distance between the CPN and the tibia at the level of the tibial cut, but not at the joint line in valgus knees. It is safer to release the posterolateral capsule at the tibial side than at the level above this. The angular location and the mediolateral or anteroposterior location of the CPN in valgus knees are similar to those of well-aligned knees. The location of the CPN in valgus knees is similar to that in well-aligned knees. The previously reported safe zone in well-aligned knees is applicable in valgus knees to protect the CPN. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Distance M-Me: A novel parameter having significant potential as a predictor of mandibular growth.

    PubMed

    Jain, Parul; Kaul, Rahul; Mukhopadhyay, Santanu; Saha, Subrata; Sarkar, Subir

    2017-01-01

    The purpose of the present study was to investigate the relationship of the measured distance between two mandibular points (distance M-Me) to chronological age and to find out whether the absolute values of distance M-Me could be classified age-wise into a unique range, which could be directly read for predicting the stage of mandibular growth. The study sample consists of lateral cephalometric records of 65 patients (34 females and 31 males; age range: 6-21 years). Chronological age was calculated in decimal years. Lateral cephalograms were assessed by two independent examiners. Points M and Me were located on the lateral cephalograms, and linear distance between them was measured. Pearson product-moment correlation coefficients showed a high correlation between chronological age and distance M-Me (0.746 for females and 0.869 for males, p < 0.01). When the values of distance M-Me were compared with chronological age, it was possible to make four age groups (for females and males separately), where each group showed a unique range of value for distance M-Me. The values increased with increasing age. Increase in value of distance M-Me with age, showing reduced individual variation, depicts a well-conserved linear dimension. Values of distance M-Me can be directly read for predicting the stage of mandibular growth and can be used as a valuable adjunct or substitute to chronological age.

  6. Estimation of safe exposure time from an ophthalmic operating microscope with regard to ultraviolet radiation and blue-light hazards to the eye

    NASA Astrophysics Data System (ADS)

    Michael, Ralph; Wegener, Alfred

    2004-08-01

    Hazards from the optical radiation of an operating microscope that cause damage at the corneal, lenticular, and retinal levels were investigated; we considered, in particular, ultraviolet radiation (UVR) and blue light. The spectral irradiance from a Zeiss operation microscope OPMI VISU 200 was measured in the corneal plane between 300 and 1100 nm. Effective irradiance and radiance were calculated with relative spectral effectiveness data from the American Conference for Governmental and Industrial Hygienists. Safe exposure time to avoid UVR injury to the lens and cornea was found to be 2 h without a filter, 4 h with a UVR filter, 200 h with a yellow filter, and 400 h with a filter combination. Safe exposure time to avoid retinal photochemical injury was found to be 3 min without a filter and with a UVR filter, 10 min with a yellow filter, and 49 min with a filter combination. The effective radiance limit for retinal thermal injury was not exceeded. The hazard due to the UVR component from the operating microscope is not critical, and operation time can be safely prolonged with the use of appropriate filters. The retinal photochemical hazard appears critical without appropriate filters, permitting only some minutes of safe exposure time. The calculated safe exposure times are for worst-case conditions and maximal light output and include a safety factor.

  7. Estimation of safe exposure time from an ophthalmic operating microscope with regard to ultraviolet radiation and blue-light hazards to the eye.

    PubMed

    Michael, Ralph; Wegener, Alfred

    2004-08-01

    Hazards from the optical radiation of an operating microscope that cause damage at the corneal, lenticular, and retinal levels were investigated; we considered, in particular, ultraviolet radiation (UVR) and blue light. The spectral irradiance from a Zeiss operation microscope OPMI VISU 200 was measured in the corneal plane between 300 and 1100 nm. Effective irradiance and radiance were calculated with relative spectral effectiveness data from the American Conference for Governmental and Industrial Hygienists. Safe exposure time to avoid UVR injury to the lens and cornea was found to be 2 h without a filter, 4 h with a UVR filter, 200 a yellow filter, and 400 h with a filter combination. Safe exposure time to avoid retinal photochemical injury was found to be 3 min without a filter and with a UVR filter, 10 min with a yellow filter, and 49 min with a filter combination. The effective radiance limit for retinal thermal injury was not exceeded. The hazard due to the UVR component from the operating microscope is not critical, and operation time can be safely prolonged with the use of appropriate filters. The retinal photochemical hazard appears critical without appropriate filters, permitting only some minutes of safe exposure time. The calculated safe exposure times are for worst-case conditions and maximal light output and include a safety factor.

  8. Optimum Projection Angle for Attaining Maximum Distance in a Soccer Punt Kick

    PubMed Central

    Linthorne, Nicholas P.; Patel, Dipesh S.

    2011-01-01

    To produce the greatest horizontal distance in a punt kick the ball must be projected at an appropriate angle. Here, we investigated the optimum projection angle that maximises the distance attained in a punt kick by a soccer goalkeeper. Two male players performed many maximum-effort kicks using projection angles of between 10° and 90°. The kicks were recorded by a video camera at 100 Hz and a 2 D biomechanical analysis was conducted to obtain measures of the projection velocity, projection angle, projection height, ball spin rate, and foot velocity at impact. The player’s optimum projection angle was calculated by substituting mathematical equations for the relationships between the projection variables into the equations for the aerodynamic flight of a soccer ball. The calculated optimum projection angles were in agreement with the player’s preferred projection angles (40° and 44°). In projectile sports even a small dependence of projection velocity on projection angle is sufficient to produce a substantial shift in the optimum projection angle away from 45°. In the punt kicks studied here, the optimum projection angle was close to 45° because the projection velocity of the ball remained almost constant across all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the projection velocity the athlete is able to achieve decreases substantially with increasing projection angle and so the optimum projection angle is well below 45°. Key points The optimum projection angle that maximizes the distance of a punt kick by a soccer goalkeeper is about 45°. The optimum projection angle is close to 45° because the projection velocity of the ball is almost the same at all projection angles. This result is in contrast to throwing and jumping for maximum distance, where the optimum projection angle is well below 45° because the projection velocity the athlete is able to achieve decreases substantially with increasing

  9. Distance dependence in photo-induced intramolecular electron transfer

    NASA Astrophysics Data System (ADS)

    Larsson, Sven; Volosov, Andrey

    1986-09-01

    The distance dependence of the rate of photo-induced electron transfer reactions is studied. A quantum mechanical method CNDO/S is applied to a series of molecules recently investigated by Hush et al. experimentally. The calculations show a large interaction through the saturated bridge which connects the two chromophores. The electronic matrix element HAB decreases a factor 10 in about 4 Å. There is also a decrease of the rate due to less exothermicity for the longer molecule. The results are in fair agreement with the experimental results.

  10. Vergence analysis reveals the influence of axial distances on accommodation with age and axial ametropia.

    PubMed

    Davies, Leon N; Dunne, Mark C M; Gibson, George A; Wolffsohn, James S

    2010-07-01

    Despite numerous investigations, the aetiology and mechanism of accommodation and presbyopia remains equivocal. Using Gaussian first-order ray tracing calculations, we examine the contribution that ocular axial distances make to the accommodation response. Further, the influence of age and ametropia are also considered. The data show that all changes in axial distances during accommodation reduce the accommodation response, with the reduction in anterior chamber depth contributing most to this overall attenuation. Although the total power loss due to the changes in axial distances remained constant with increasing age, hyperopes exhibited less accommodation than myopes. The study, therefore, enhances our understanding of biometric accommodative changes and demonstrates the utility of vergence analysis in the assessment of accommodation.

  11. Going the Distance.

    ERIC Educational Resources Information Center

    Leno, Arthur J.

    2003-01-01

    Describes the development and implementation of the distance education program at Peirce College. This Internet-mediated distance learning program focuses on practical fields of study, drawing on the college's strengths in business administration, information technology, and paralegal studies. (SLD)

  12. Safe Schools, Safe Students. Proceedings of the National Education Goals Panel/National Alliance of Pupil Services Organizations Conference on "Safe Schools, Safe Students: A Collaborative Approach to Achieving Safe, Disciplined, and Drug-free Schools Conducive to Learning" (Washington, D.C., October 28-29, 1994).

    ERIC Educational Resources Information Center

    Talley, Ronda C., Ed.; Walz, Garry R., Ed.

    The "Safe Schools, Safe Students" conference brought together leading researchers and practitioners in order to share knowledge about innovative safety strategies being used in America's schools. The papers here represent the thinking of scientific experts and school-based pupil service providers who are implementing programs to prevent…

  13. Making Distance Education Borderless.

    ERIC Educational Resources Information Center

    Srisa-An, Wichit

    1997-01-01

    Begins with a tribute to Professor G. Ram Reddy (founder of Indira Gandhi National Open University), then focuses on enhancing the role of open universities in providing borderless distance education. Highlights include the need for open distance-education; philosophy and vision; the distance teaching system; the role of information technology;…

  14. Keeping one's distance: the influence of spatial distance cues on affect and evaluation.

    PubMed

    Williams, Lawrence E; Bargh, John A

    2008-03-01

    Current conceptualizations of psychological distance (e.g., construal-level theory) refer to the degree of overlap between the self and some other person, place, or point in time. We propose a complementary view in which perceptual and motor representations of physical distance influence people's thoughts and feelings without reference to the self, extending research and theory on the effects of distance into domains where construal-level theory is silent. Across four experiments, participants were primed with either spatial closeness or spatial distance by plotting an assigned set of points on a Cartesian coordinate plane. Compared with the closeness prime, the distance prime produced greater enjoyment of media depicting embarrassment (Study 1), less emotional distress from violent media (Study 2), lower estimates of the number of calories in unhealthy food (Study 3), and weaker reports of emotional attachments to family members and hometowns (Study 4). These results support a broader conceptualization of distance-mediated effects on judgment and affect.

  15. SU-F-T-125: Radial Dose Distributions From Carbon Ions of Therapeutic Energies Calculated with Geant4-DNA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vassiliev, O

    Purpose: Radial dose distribution D(r) is the dose as a function of lateral distance from the path of a heavy charged particle. Its main application is in modelling of biological effects of heavy ions, including applications to hadron therapy. It is the main physical parameter of a broad group of radiobiological models known as the amorphous track models. Our purpose was to calculate D(r) with Monte Carlo for carbon ions of therapeutic energies, find a simple formula for D(r) and fit it to the Monte Carlo data. Methods: All calculations were performed with Geant4-DNA code, for carbon ion energies frommore » 10 to 400 MeV/u (ranges in water: ∼ 0.4 mm to 27 cm). The spatial resolution of dose distribution in the lateral direction was 1 nm. Electron tracking cut off energy was 11 eV (ionization threshold). The maximum lateral distance considered was 10 µm. Over this distance, D(r) decreases with distance by eight orders of magnitude. Results: All calculated radial dose distributions had a similar shape dominated by the well-known inverse square dependence on the distance. Deviations from the inverse square law were observed close to the beam path (r<10 nm) and at large distances (r >1 µm). At small and large distances D(r) decreased, respectively, slower and faster than the inverse square of distance. A formula for D(r) consistent with this behavior was found and fitted to the Monte Carlo data. The accuracy of the fit was better than 10% for all distances considered. Conclusion: We have generated a set of radial dose distributions for carbon ions that covers the entire range of therapeutic energies, for distances from the ion path of up to 10 µm. The latter distance is sufficient for most applications because dose beyond 10 µm is extremely low.« less

  16. Lack of recruitment in Lavandula stoechas subsp. pedunculata: a case of safe-site limitation

    NASA Astrophysics Data System (ADS)

    Sánchez, Ana M.; Peco, Begoña

    2007-01-01

    Lavandula stoechas subsp. pedunculata regeneration depends exclusively on the establishment of new individuals. Seed availability and seedling emergence and survival are therefore critical life stages and processes for species regeneration. In this study, seedling emergence and survival was monitored for two years in the scrub, both in clearings and adjacent to adult plants, and the surrounding perennial grassland, at 1, 3 and 5 m from the scrub. Soil seed bank spatial distribution was also studied for one year in the same two habitats, using the same sampling design. Soil seed availability in the scrub is high regardless of the distance from the adult individuals. On the contrary, the adjacent grassland shows a drastic fall in seed density, and almost no seedlings were observed there. In the scrub, seedling density was negatively related to distance from the three nearest adult plants in the clearings, and positively related to adult plant size beneath the adult Lavandula plants. There was also a negative relationship between seedling density and the percentage of bare soil. Only one seedling survived the first drought period, with no detection of effects of either position with respect to adult individuals or seedling density. We hypothesized that the study populations suffer a lack of appropriate safe sites within the scrubland while in the adjacent perennial grassland, observed low seed availability was added to safe-site limitation. That results in a lack of successful seedling establishments and a poor expansion potential of Lavandula scrublands, whose edges remain static in the short and medium term. As found in other Mediterranean scrubland, recruitment may only occur in years with particularly favourable weather, under disturbance regimes that increase seedling survival probability or when external dispersal agents increased seed availability in adequate places for Lavandula establishment.

  17. Source-receptor matrix calculation with a Source-receptor matrix calculation with a backward mode

    NASA Astrophysics Data System (ADS)

    Seibert, P.; Frank, A.

    2003-08-01

    The possibility to calculate linear-source receptor relationships for the transport of atmospheric trace substances with a Lagrangian particle dispersion model (LPDM) running in backward mode is shown and presented with many tests and examples. The derivation includes the action of sources and of any first-order processes (transformation with prescribed rates, dry and wet deposition, radioactive decay, ...). The backward mode is computationally advantageous if the number of receptors is less than the number of sources considered. The combination of an LPDM with the backward (adjoint) methodology is especially attractive for the application to point measurements, which can be handled without artificial numerical diffusion. Practical hints are provided for source-receptor calculations with different settings, both in forward and backward mode. The equivalence of forward and backward calculations is shown in simple tests for release and sampling of particles, pure wet deposition, pure convective redistribution and realistic transport over a short distance. Furthermore, an application example explaining measurements of Cs-137 in Stockholm as transport from areas contaminated heavily in the Chernobyl disaster is included.

  18. Steering teens safe: a randomized trial of a parent-based intervention to improve safe teen driving.

    PubMed

    Peek-Asa, Corinne; Cavanaugh, Joseph E; Yang, Jingzhen; Chande, Vidya; Young, Tracy; Ramirez, Marizen

    2014-07-31

    Crashes are the leading cause of death for teens, and parent-based interventions are a promising approach. We assess the effectiveness of Steering Teens Safe, a parent-focused program to increase safe teen driving. Steering Teens Safe aimed to improve parental communication with teens about safe driving using motivational interviewing techniques in conjunction with 19 safe driving lessons. A randomized controlled trial involved 145 parent-teen dyads (70 intervention and 75 control). Intervention parents received a 45-minute session to learn the program with four follow-up phone sessions, a DVD, and a workbook. Control parents received a standard brochure about safe driving. Scores were developed to measure teen-reported quantity and quality of parental communication about safe driving. The main outcome measure was a previously validated Risky Driving Score reported by teens. Because the Score was highly skewed, a generalized linear model based on a gamma distribution was used for analysis. Intervention teens ranked their parent's success in talking about driving safety higher than control teens (p = 0.035) and reported that their parents talked about more topics (non-significant difference). The Risky Driving Score was 21% lower in intervention compared to control teens (85% CI = 0.60, 1.00). Interaction between communication quantity and the intervention was examined. Intervention teens who reported more successful communication had a 42% lower Risky Driving Score (95% CI = 0.37, 0.94) than control parents with less successful communication. This program had a positive although not strong effect, and it may hold the most promise in partnership with other programs, such as Driver's Education or Graduated Driver's License policies. ClinicalTrials.gov NCT01014923. Registered Nov. 16, 2009.

  19. Kinematic Distances: A Monte Carlo Method

    NASA Astrophysics Data System (ADS)

    Wenger, Trey V.; Balser, Dana S.; Anderson, L. D.; Bania, T. M.

    2018-03-01

    Distances to high-mass star-forming regions (HMSFRs) in the Milky Way are a crucial constraint on the structure of the Galaxy. Only kinematic distances are available for a majority of the HMSFRs in the Milky Way. Here, we compare the kinematic and parallax distances of 75 Galactic HMSFRs to assess the accuracy of kinematic distances. We derive the kinematic distances using three different methods: the traditional method using the Brand & Blitz rotation curve (Method A), the traditional method using the Reid et al. rotation curve and updated solar motion parameters (Method B), and a Monte Carlo technique (Method C). Methods B and C produce kinematic distances closest to the parallax distances, with median differences of 13% (0.43 {kpc}) and 17% (0.42 {kpc}), respectively. Except in the vicinity of the tangent point, the kinematic distance uncertainties derived by Method C are smaller than those of Methods A and B. In a large region of the Galaxy, the Method C kinematic distances constrain both the distances and the Galactocentric positions of HMSFRs more accurately than parallax distances. Beyond the tangent point along ℓ = 30°, for example, the Method C kinematic distance uncertainties reach a minimum of 10% of the parallax distance uncertainty at a distance of 14 {kpc}. We develop a prescription for deriving and applying the Method C kinematic distances and distance uncertainties. The code to generate the Method C kinematic distances is publicly available and may be utilized through an online tool.

  20. Research on numerical simulation and protection of transient process in long-distance slurry transportation pipelines

    NASA Astrophysics Data System (ADS)

    Lan, G.; Jiang, J.; Li, D. D.; Yi, W. S.; Zhao, Z.; Nie, L. N.

    2013-12-01

    The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system.

  1. Safe biodegradable fluorescent particles

    DOEpatents

    Martin, Sue I [Berkeley, CA; Fergenson, David P [Alamo, CA; Srivastava, Abneesh [Santa Clara, CA; Bogan, Michael J [Dublin, CA; Riot, Vincent J [Oakland, CA; Frank, Matthias [Oakland, CA

    2010-08-24

    A human-safe fluorescence particle that can be used for fluorescence detection instruments or act as a safe simulant for mimicking the fluorescence properties of microorganisms. The particle comprises a non-biological carrier and natural fluorophores encapsulated in the non-biological carrier. By doping biodegradable-polymer drug delivery microspheres with natural or synthetic fluorophores, the desired fluorescence can be attained or biological organisms can be simulated without the associated risks and logistical difficulties of live microorganisms.

  2. Safe landing area determination for a Moon lander by reachability analysis

    NASA Astrophysics Data System (ADS)

    Arslantaş, Yunus Emre; Oehlschlägel, Thimo; Sagliano, Marco

    2016-11-01

    In the last decades developments in space technology paved the way to more challenging missions like asteroid mining, space tourism and human expansion into the Solar System. These missions result in difficult tasks such as guidance schemes for re-entry, landing on celestial bodies and implementation of large angle maneuvers for spacecraft. There is a need for a safety system to increase the robustness and success of these missions. Reachability analysis meets this requirement by obtaining the set of all achievable states for a dynamical system starting from an initial condition with given admissible control inputs of the system. This paper proposes an algorithm for the approximation of nonconvex reachable sets (RS) by using optimal control. Therefore subset of the state space is discretized by equidistant points and for each grid point a distance function is defined. This distance function acts as an objective function for a related optimal control problem (OCP). Each infinite dimensional OCP is transcribed into a finite dimensional Nonlinear Programming Problem (NLP) by using Pseudospectral Methods (PSM). Finally, the NLPs are solved using available tools resulting in approximated reachable sets with information about the states of the dynamical system at these grid points. The algorithm is applied on a generic Moon landing mission. The proposed method computes approximated reachable sets and the attainable safe landing region with information about propellant consumption and time.

  3. Safe Haven.

    ERIC Educational Resources Information Center

    Bush, Gail

    2003-01-01

    Discusses school libraries as safe havens for teenagers and considers elements that foster that atmosphere, including the physical environment, lack of judgments, familiarity, leisure, and a welcoming nature. Focuses on the importance of relationships, and taking the time to listen to teens and encourage them. (LRW)

  4. The statistical fluctuation study of quantum key distribution in means of uncertainty principle

    NASA Astrophysics Data System (ADS)

    Liu, Dunwei; An, Huiyao; Zhang, Xiaoyu; Shi, Xuemei

    2018-03-01

    Laser defects in emitting single photon, photon signal attenuation and propagation of error cause our serious headaches in practical long-distance quantum key distribution (QKD) experiment for a long time. In this paper, we study the uncertainty principle in metrology and use this tool to analyze the statistical fluctuation of the number of received single photons, the yield of single photons and quantum bit error rate (QBER). After that we calculate the error between measured value and real value of every parameter, and concern the propagation error among all the measure values. We paraphrase the Gottesman-Lo-Lutkenhaus-Preskill (GLLP) formula in consideration of those parameters and generate the QKD simulation result. In this study, with the increase in coding photon length, the safe distribution distance is longer and longer. When the coding photon's length is N = 10^{11}, the safe distribution distance can be almost 118 km. It gives a lower bound of safe transmission distance than without uncertainty principle's 127 km. So our study is in line with established theory, but we make it more realistic.

  5. Radio Astronomers Set New Standard for Accurate Cosmic Distance Measurement

    NASA Astrophysics Data System (ADS)

    1999-06-01

    wavelength of the radio waves caused by the Doppler effect. The gas is orbiting at a speed of more than two million miles per hour. The orbiting disk of gas is almost edge-on as viewed from Earth. The astronomers obtained the orbital speeds and the positions of the masers in the disk by measuring the Doppler Shift of the masers at the disk's sides, where the gas is moving almost directly away from the Earth on one side and toward the Earth on the other. Measurements of the different orbital speeds at different distances from the black hole, made in 1994, allowed them to determine the mass of the black hole. These measurements required the great resolving power, or ability to see fine detail, of the VLBA. This picture of an orbiting disk was confirmed by measurement of centrifugal acceleration, according to the scientists. The newest observations were focused on maser "spots" on the near edge of the disk, where orbital motion shifts their position in the sky, though by an extremely small amount. The VLBA, however, was able to detect this extremely small movement, called "proper motion" by astronomers. This motion was detected by observing the galaxy at 4- to 8-month intervals over more than three years. "By knowing the speed at which the gas is orbiting and then measuring its motion across the sky, we can use plain old trigonometry to calculate the distance," Greenhill said. He added, however, that "you need a bit of luck to be able to do this. So far, we know of only 22 galaxies with water masers in their nuclear regions that also are relatively nearby. Then, the geometry of the disk, relative to Earth, has to be right to allow us to make such a measurement" The VLBA measurement of NGC 4258's distance differs significantly from the distance to that galaxy determined through HST observations of Cepheid variable stars. Using such stars, a team of astronomers led by University of California-Berkeley scientist Eyal Maoz has made preliminary and as-yet unpublished estimates of

  6. Braking Distance of Hoist Conveyances Required for Safe Stopping Under the Conditions of Emergency Braking

    NASA Astrophysics Data System (ADS)

    Wolny, Stanisław

    2017-06-01

    This study investigates selected aspects of the dynamic behaviour of mine hoists during the emergency braking in an event of overtravel. Characteristics of the braking force that needs to be applied in the headgear and in the pit bottom to arrest the conveyance in the event of an overtravel are derived from laboratory and industrial test data and recalling the results reported in literature. The real hoist installation is replaced by a model whereby the equations of motion of rope elements are written as for elastic strings, taking into account the variable length of the hoisting rope section between the Koepe pulley and the conveyance being arrested in the head tower. Analytical formulas are provided whereby the displacement of the top conveyance with the payload for the constant elasticity coefficient of the hoisting rope section between the conveyance being arrested in the head tower and the Koepe pulley is expressed as the function of the braking force and of the operational parameters of the hoist gear. The hoist operation is investigated in the event of emergency braking, taking into account the two aspects of the cycle: - the time required for the conveyance to be stopped, - the distance travelled by the conveyance until it is stopped. The results of the dynamic analysis of the hoist installation in the conditions of emergency braking may be utilised in selection of the effective and adequate braking system guaranteeing the safety of the system operation.

  7. Suppression of Systematic Errors of Electronic Distance Meters for Measurement of Short Distances

    PubMed Central

    Braun, Jaroslav; Štroner, Martin; Urban, Rudolf; Dvořáček, Filip

    2015-01-01

    In modern industrial geodesy, high demands are placed on the final accuracy, with expectations currently falling below 1 mm. The measurement methodology and surveying instruments used have to be adjusted to meet these stringent requirements, especially the total stations as the most often used instruments. A standard deviation of the measured distance is the accuracy parameter, commonly between 1 and 2 mm. This parameter is often discussed in conjunction with the determination of the real accuracy of measurements at very short distances (5–50 m) because it is generally known that this accuracy cannot be increased by simply repeating the measurement because a considerable part of the error is systematic. This article describes the detailed testing of electronic distance meters to determine the absolute size of their systematic errors, their stability over time, their repeatability and the real accuracy of their distance measurement. Twenty instruments (total stations) have been tested, and more than 60,000 distances in total were measured to determine the accuracy and precision parameters of the distance meters. Based on the experiments’ results, calibration procedures were designed, including a special correction function for each instrument, whose usage reduces the standard deviation of the measurement of distance by at least 50%. PMID:26258777

  8. Suppression of Systematic Errors of Electronic Distance Meters for Measurement of Short Distances.

    PubMed

    Braun, Jaroslav; Štroner, Martin; Urban, Rudolf; Dvoček, Filip

    2015-08-06

    In modern industrial geodesy, high demands are placed on the final accuracy, with expectations currently falling below 1 mm. The measurement methodology and surveying instruments used have to be adjusted to meet these stringent requirements, especially the total stations as the most often used instruments. A standard deviation of the measured distance is the accuracy parameter, commonly between 1 and 2 mm. This parameter is often discussed in conjunction with the determination of the real accuracy of measurements at very short distances (5-50 m) because it is generally known that this accuracy cannot be increased by simply repeating the measurement because a considerable part of the error is systematic. This article describes the detailed testing of electronic distance meters to determine the absolute size of their systematic errors, their stability over time, their repeatability and the real accuracy of their distance measurement. Twenty instruments (total stations) have been tested, and more than 60,000 distances in total were measured to determine the accuracy and precision parameters of the distance meters. Based on the experiments' results, calibration procedures were designed, including a special correction function for each instrument, whose usage reduces the standard deviation of the measurement of distance by at least 50%.

  9. Distance Education in Southern Africa Conference, 1987. Papers 2: Issues in Education and Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Eighteen papers from the University of South Africa's Conference on Distance Education are presented on issues in education and distance education. They include: "Distance Education in Africa's Educational Development: The Case of Ghana" (Joe K. Ansere); "Distance Education: A Solution to the Economic Problems of Education in…

  10. Distance matrix-based approach to protein structure prediction.

    PubMed

    Kloczkowski, Andrzej; Jernigan, Robert L; Wu, Zhijun; Song, Guang; Yang, Lei; Kolinski, Andrzej; Pokarowski, Piotr

    2009-03-01

    dynamics. After structure matching, we apply principal component analysis (PCA) to obtain the important apparent motions for both bound and unbound structures. There are significant similarities between the first few key motions and the first few low-frequency normal modes calculated from a static representative structure with an elastic network model (ENM) that is based on the contact matrix C (related to D), strongly suggesting that the variations among the observed structures and the corresponding conformational changes are facilitated by the low-frequency, global motions intrinsic to the structure. Similarities are also found when the approach is applied to an NMR ensemble, as well as to atomic molecular dynamics (MD) trajectories. Thus, a sufficiently large number of experimental structures can directly provide important information about protein dynamics, but ENM can also provide a similar sampling of conformations. Finally, we use distance constraints from databases of known protein structures for structure refinement. We use the distributions of distances of various types in known protein structures to obtain the most probable ranges or the mean-force potentials for the distances. We then impose these constraints on structures to be refined or include the mean-force potentials directly in the energy minimization so that more plausible structural models can be built. This approach has been successfully used by us in 2006 in the CASPR structure refinement (http://predictioncenter.org/caspR).

  11. More than a Safe Space

    ERIC Educational Resources Information Center

    Sadowski, Michael

    2016-01-01

    Over the past three decades, much of the conversation about LGBTQ students in schools has centered on safety--anti-bullying policies, the "safe space" of gay-straight alliances, and "safe zones" marked by rainbow-colored stickers on classroom doors. In this article, Michael Sadowski argues that it's time to move beyond safety…

  12. The semantic distance task: Quantifying semantic distance with semantic network path length.

    PubMed

    Kenett, Yoed N; Levi, Effi; Anaki, David; Faust, Miriam

    2017-09-01

    Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We propose a novel approach to computing semantic distance, based on network science methodology. Path length in a semantic network represents the amount of steps needed to traverse from 1 word in the network to the other. We examine whether path length can be used as a measure of semantic distance, by investigating how path length affect performance in a semantic relatedness judgment task and recall from memory. Our results show a differential effect on performance: Up to 4 steps separating between word-pairs, participants exhibit an increase in reaction time (RT) and decrease in the percentage of word-pairs judged as related. From 4 steps onward, participants exhibit a significant decrease in RT and the word-pairs are dominantly judged as unrelated. Furthermore, we show that as path length between word-pairs increases, success in free- and cued-recall decreases. Finally, we demonstrate how our measure outperforms computational methods measuring semantic distance (LSA and positive pointwise mutual information) in predicting participants RT and subjective judgments of semantic strength. Thus, we provide a computational alternative to computing semantic distance. Furthermore, this approach addresses key issues in cognitive theory, namely the breadth of the spreading activation process and the effect of semantic distance on memory retrieval. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Reducing the distance: equity issues in distance learning in public education

    NASA Astrophysics Data System (ADS)

    Campbell, Patricia B.; Storo, Jennifer

    1996-12-01

    Distance learning and educational equity both began with an emphasis on access, on providing underserved students with an increased access to education. Today definitions of equity have gone beyond simple access to include equal or equivalent treatment and outcomes while definitions of underserved students have expanded to include girls, children of color, children with limited English proficiency and children with disabilities. At the same time the definition of distance learning has expanded to include new technologies, new audiences and new roles. Based on these new definitions and roles, the article raises a number of equity challenges for distance learning educators centering around who is taught, what is taught and how the teaching is done. To answer these challenges, a series of recommendations are suggested that educators can implement to make distance learning a leader in increasing educational equity for all students. The time to act is now.

  14. Development of an in-fiber white-light interferometric distance sensor for absolute measurement of arbitrary small distances.

    PubMed

    Majumdar, Ayan; Huang, Haiying

    2008-05-20

    The fabrication, implementation, and evaluation of an in-fiber white-light interferometric distance sensor that is capable of measuring the absolute value of an arbitrary small distance are presented. Taking advantage of the mode-coupling effect of a long-period fiber grating, an additional cavity distance is added to the optical path difference of the distance sensor; therefore, it can generate a sufficient number of fringes for distance demodulation even if the free-space cavity distance is very small. It is experimentally verified that the distance sensor is capable of measuring small distances that are beyond the capability of a Fabry-Perot interferometric distance sensor.

  15. Oscillation properties of active and sterile neutrinos and neutrino anomalies at short distances

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khruschov, V. V., E-mail: khruschov-vv@nrcki.ru; Fomichev, S. V., E-mail: fomichev-sv@nrcki.ru; Titov, O. A., E-mail: titov-oa@nrcki.ru

    2016-09-15

    A generalized phenomenological (3 + 2 + 1) model featuring three active and three sterile neutrinos that is intended for calculating oscillation properties of neutrinos for the case of a normal active neutrino mass hierarchy and a large splitting between the mass of one sterile neutrino and the masses of the other two sterile neutrinos is considered. A new parametrization and a specific form of the general mixing matrix are proposed for active and sterile neutrinos with allowance for possible CP violation in the lepton sector, and test values are chosen for the neutrino masses and mixing parameters. The probabilitiesmore » for the transitions between different neutrino flavors are calculated, and graphs representing the probabilities for the disappearance of muon neutrinos/antineutrinos and the appearance of electron neutrinos/antineutrinos in a beam of muon neutrinos/antineutrinos versus the distance from the neutrino source for various values of admissible model parameters at neutrino energies not higher than 50 MeV, as well as versus the ratio of this distance to the neutrino energy, are plotted. It is shown that the short-distance accelerator anomaly in neutrino data (LNSD anomaly) can be explained in the case of a specific mixing matrix for active and sterile neutrinos (which belongs to the a{sub 2} type) at the chosen parameter values. The same applies to the short-distance reactor and gallium anomalies. The theoretical results obtained in the present study can be used to interpret and predict the results of ground-based neutrino experiments aimed at searches for sterile neutrinos, as well as to analyze some astrophysical observational data.« less

  16. Evolution of the Hubble Space Telescope Safing Systems

    NASA Technical Reports Server (NTRS)

    Pepe, Joyce; Myslinski, Michael

    2006-01-01

    The Hubble Space Telescope (HST) was launched on April 24 1990, with an expected lifespan of 15 years. Central to the spacecraft design was the concept of a series of on-orbit shuttle servicing missions permitting astronauts to replace failed equipment, update the scientific instruments and keep the HST at the forefront of astronomical discoveries. One key to the success of the Hubble mission has been the robust Safing systems designed to monitor the performance of the observatory and to react to keep the spacecraft safe in the event of equipment anomaly. The spacecraft Safing System consists of a range of software tests in the primary flight computer that evaluate the performance of mission critical hardware, safe modes that are activated when the primary control mode is deemed inadequate for protecting the vehicle, and special actions that the computer can take to autonomously reconfigure critical hardware. The HST Safing System was structured to autonomously detect electrical power system, data management system, and pointing control system malfunctions and to configure the vehicle to ensure safe operation without ground intervention for up to 72 hours. There is also a dedicated safe mode computer that constantly monitors a keep-alive signal from the primary computer. If this signal stops, the safe mode computer shuts down the primary computer and takes over control of the vehicle, putting it into a safe, low-power configuration. The HST Safing system has continued to evolve as equipment has aged, as new hardware has been installed on the vehicle, and as the operation modes have matured during the mission. Along with the continual refinement of the limits used in the safing tests, several new tests have been added to the monitoring system, and new safe modes have been added to the flight software. This paper will focus on the evolution of the HST Safing System and Safing tests, and the importance of this evolution to prolonging the science operations of the

  17. Distance Magic-Type and Distance Antimagic-Type Labelings of Graphs

    NASA Astrophysics Data System (ADS)

    Freyberg, Bryan J.

    Generally speaking, a distance magic-type labeling of a graph G of order n is a bijection l from the vertex set of the graph to the first n natural numbers or to the elements of a group of order n, with the property that the weight of each vertex is the same. The weight of a vertex x is defined as the sum (or appropriate group operation) of all the labels of vertices adjacent to x. If instead we require that all weights differ, then we refer to the labeling as a distance antimagic-type labeling. This idea can be generalized for directed graphs; the weight will take into consideration the direction of the arcs. In this manuscript, we provide new results for d-handicap labeling, a distance antimagic-type labeling, and introduce a new distance magic-type labeling called orientable Gamma-distance magic labeling. A d-handicap distance antimagic labeling (or just d-handicap labeling for short) of a graph G = ( V,E) of order n is a bijection l from V to the set {1,2,...,n} with induced weight function [special characters omitted]. such that l(xi) = i and the sequence of weights w(x 1),w(x2),...,w (xn) forms an arithmetic sequence with constant difference d at least 1. If a graph G admits a d-handicap labeling, we say G is a d-handicap graph. A d-handicap incomplete tournament, H(n,k,d ) is an incomplete tournament of n teams ranked with the first n natural numbers such that each team plays exactly k games and the strength of schedule of the ith ranked team is d more than the i + 1st ranked team. That is, strength of schedule increases arithmetically with strength of team. Constructing an H(n,k,d) is equivalent to finding a d-handicap labeling of a k-regular graph of order n.. In Chapter 2 we provide general constructions for every d for large classes of both n and k, providing breadfth and depth to the catalog of known H(n,k,d)'s. In Chapters 3 - 6, we introduce a new type of labeling called orientable Gamma-distance magic labeling. Let Gamma be an abelian group of order

  18. Managing Cassini Safe Mode Attitude at Saturn

    NASA Technical Reports Server (NTRS)

    Burk, Thomas A.

    2010-01-01

    The Cassini spacecraft was launched on October 15, 1997 and arrived at Saturn on June 30, 2004. It has performed detailed observations and remote sensing of Saturn, its rings, and its satellites since that time. In the event safe mode interrupts normal orbital operations, Cassini has flight software fault protection algorithms to detect, isolate, and recover to a thermally safe and commandable attitude and then wait for further instructions from the ground. But the Saturn environment is complex, and safety hazards change depending on where Cassini is in its orbital trajectory around Saturn. Selecting an appropriate safe mode attitude that insures safe operation in the Saturn environment, including keeping the star tracker field of view clear of bright bodies, while maintaining a quiescent, commandable attitude, is a significant challenge. This paper discusses the Cassini safe table management strategy and the key criteria that must be considered, especially during low altitude flybys of Titan, in deciding what spacecraft attitude should be used in the event of safe mode.

  19. Experiential Teaching Increases Medication Calculation Accuracy Among Baccalaureate Nursing Students.

    PubMed

    Hurley, Teresa V

    Safe medication administration is an international goal. Calculation errors cause patient harm despite education. The research purpose was to evaluate the effectiveness of an experiential teaching strategy to reduce errors in a sample of 78 baccalaureate nursing students at a Northeastern college. A pretest-posttest design with random assignment into equal-sized groups was used. The experiential strategy was more effective than the traditional method (t = -0.312, df = 37, p = .004, 95% CI) with a reduction in calculation errors. Evaluations of error type and teaching strategies are indicated to facilitate course and program changes.

  20. "Safe Schools within Safe Communities: A Regional Summit in the Heartland." Policy Briefs Special Report.

    ERIC Educational Resources Information Center

    Huertas, Aurelio, Jr.; Sullivan, Carol

    This report documents the proceedings of a regional policy seminar hosted by the Iowa Department of Education with support from the North Central Regional Educational Laboratory (NCREL) and the Midwest Regional Center for Drug-Free Schools and Communities (MRC). The seminar, "Safe Schools Within Safe Communities," was held on September 19-20,…

  1. Edit distance for marked point processes revisited: An implementation by binary integer programming

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hirata, Yoshito; Aihara, Kazuyuki

    2015-12-15

    We implement the edit distance for marked point processes [Suzuki et al., Int. J. Bifurcation Chaos 20, 3699–3708 (2010)] as a binary integer program. Compared with the previous implementation using minimum cost perfect matching, the proposed implementation has two advantages: first, by using the proposed implementation, we can apply a wide variety of software and hardware, even spin glasses and coherent ising machines, to calculate the edit distance for marked point processes; second, the proposed implementation runs faster than the previous implementation when the difference between the numbers of events in two time windows for a marked point process ismore » large.« less

  2. Testing the Distance Scale of the Gaia TGAS Catalogue by the Kinematic Method

    NASA Astrophysics Data System (ADS)

    Bobylev, V. V.; Bajkova, A. T.

    2018-03-01

    We have studied the simultaneous and separate solutions of the basic kinematic equations obtained using the stellar velocities calculated on the basis of data from the Gaia TGAS and RAVE5 catalogues. By comparing the values of Ω'0 found by separately analyzing only the line-of-sight velocities of stars and only their proper motions, we have determined the distance scale correction factor p to be close to unity, 0.97 ± 0.04. Based on the proper motions of stars from the Gaia TGAS catalogue with relative trigonometric parallax errors less than 10% (they are at a mean distance of 226 pc), we have found the components of the group velocity vector for the sample stars relative to the Sun ( U, V, W)⊙ = (9.28, 20.35, 7.36) ± (0.05, 0.07, 0.05) km s-1, the angular velocity of Galactic rotation Ω0 = 27.24 ± 0.30 km s-1 kpc-1, and its first derivative Ω'0 = -3.77 ± 0.06 km s-1 kpc-2; here, the circular rotation velocity of the Sun around the Galactic center is V 0 = 218 ± 6 km s-1 kpc (for the adopted distance R 0 = 8.0 ± 0.2 kpc), while the Oort constants are A = 15.07 ± 0.25 km s-1 kpc-1 and B = -12.17 ± 0.39 km s-1 kpc-1, p = 0.98 ± 0.08. The kinematics of Gaia TGAS stars with parallax errors more than 10% has been studied by invoking the distances from a paper by Astraatmadja and Bailer-Jones that were corrected for the Lutz-Kelker bias. We show that the second derivative of the angular velocity of Galactic rotation Ω'0 = 0.864 ± 0.021 km s-1 kpc-3 is well determined from stars at a mean distance of 537 pc. On the whole, we have found that the distances of stars from the Gaia TGAS catalogue calculated using their trigonometric parallaxes do not require any additional correction factor.

  3. Safe Use Practices for Pesticides

    Science.gov Websites

    ; Environment Human Health Animal Health Safe Use Practices Food Safety Environment Air Water Soil Wildlife Ingredients Low-Risk Pesticides Organic Pesticide Ingredients Pesticide Incidents Human Exposure Pet Exposure Home Page Pesticide Health and Safety Information Safe Use Practices for Pesticides Related Topics

  4. Is Prevent a Safe Space?

    ERIC Educational Resources Information Center

    Ramsay, Peter

    2017-01-01

    In this article, I test the claims of the UK government and universities that the Prevent programme aims to create a safe space for the discussion of "extremist" ideas in universities. I do this by comparing the main elements of the Prevent duty that has been imposed on universities with those of safe spaces as imagined by student…

  5. 75 FR 29391 - National Safe Boating Week, 2010

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... Safe Boating Week, 2010 By the President of the United States of America A Proclamation Our Nation's... National Safe Boating Week to practicing safe techniques so boaters of all ages can enjoy this pastime... annually the 7-day period prior to Memorial Day weekend as ``National Safe Boating Week.'' NOW, THEREFORE...

  6. Anatomical recommendations for safe botulinum toxin injection into temporalis muscle: a simplified reproducible approach.

    PubMed

    Lee, Won-Kang; Bae, Jung-Hee; Hu, Kyung-Seok; Kato, Takafumi; Kim, Seong-Taek

    2017-03-01

    The objective of this study was to simplify the anatomically safe and reproducible approach for BoNT injection and to generate a detailed topographic map of the important anatomical structures of the temporal region by dividing the temporalis into nine equally sized compartments. Nineteen sides of temporalis muscle were used. The topographies of the superficial temporal artery, middle temporal vein, temporalis tendon, and the temporalis muscle were evaluated. Also evaluated was the postural relations among the foregoing anatomical structures in the temporalis muscle, pivoted upon a total of nine compartments. The temporalis above the zygomatic arch exhibited an oblique quadrangular shape with rounded upper right and left corners. The distance between the anterior and posterior margins of the temporalis muscle was equal to the width of the temporalis rectangle, and the distance between the reference line and the superior temporalis margin was equal to its height. The mean ratio of width to height was 5:4. We recommend compartments Am, Mu, and Pm (coordinates of the rectangular outline) as areas in the temporal region for BoNT injection, because using these sites will avoid large blood vessels and tendons, thus improving the safety and reproducibility of the injection.

  7. Microbial risk assessment in heterogeneous aquifers: 2. Infection risk sensitivity

    NASA Astrophysics Data System (ADS)

    Molin, S.; Cvetkovic, V.; StenströM, T. A.

    2010-05-01

    The entire chain of events of human disease transmitted through contaminated water, from pathogen introduction into the source (E. coli, rotavirus, and Hepatitis A), pathogen migration through the aquifer pathway, to ingestion via a supply well, and finally, the potential infection in the human host, is investigated. The health risk calculations are based on a relevant hazardous event with safe setback distances estimated by considering the infection risk from peak exposure in compliance with an acceptable level defined by a regulatory agency. A site-specific hypothetical scenario is illustrated for an aquifer with similar characteristics as the Cape Cod site, Massachusetts (United States). Relatively large variation of safe distances for the three index pathogens is found; individually, none of the index pathogens could predict the safe distance under the wide range of conditions investigated. It is shown that colloid filtration theory (CFT) with spatially variable attachment-detachment rates yields significantly different results from the effective CFT model (i.e., assuming spatially constant parameters).

  8. The perceptions of nurses towards barriers to the safe administration of medicines in mental health settings.

    PubMed

    Hemingway, Steve; McCann, Terence; Baxter, Hazel; Smith, George; Burgess-Dawson, Rebecca; Dewhirst, Kate

    2015-12-01

    The purpose of this study was to investigate perceptions of barriers to safe administration of medicines in mental health settings. A cross-sectional survey was used, and 70 mental health nurses and 41 students were recruited from a mental health trust and a university in Yorkshire, UK. Respondents completed a questionnaire comprising closed- and open-response questions. One item, which contained seven sub-items, addressed barriers to safe administration of medication. Seven themes--five nurse- and prescriber-focused and two service user-focused--were abstracted from the data, depicting a range of barriers to safe administration of medicines. Nurse- and prescriber-focused themes included environmental distractions, insufficient pharmacological knowledge, poorly written and incomplete medication documentation, inability to calculate medication dosage correctly, and work-related pressure. Service user-focused themes comprised poor adherence to medication regimens, and cultural and linguistic communication barriers with service users. Tackling medication administration error is predominantly an organizational rather than individual practitioner responsibility. © 2014 Wiley Publishing Asia Pty Ltd.

  9. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  10. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  11. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  12. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  13. 30 CFR 77.312 - Fail safe monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe monitoring systems. 77.312 Section 77... Thermal Dryers § 77.312 Fail safe monitoring systems. Thermal dryer systems and controls shall be protected by a fail safe monitoring system which will safely shut down the system and any related equipment...

  14. 29 CFR 1915.15 - Maintenance of safe conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment § 1915.15 Maintenance of safe... into spaces that have been certified “Safe for Workers” or “Safe for Hot Work” shall be disconnected... certificates. A competent person shall visually inspect and test each space certified as “Safe for Workers” or...

  15. 29 CFR 1915.15 - Maintenance of safe conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Enclosed Spaces and Other Dangerous Atmospheres in Shipyard Employment § 1915.15 Maintenance of safe... into spaces that have been certified “Safe for Workers” or “Safe for Hot Work” shall be disconnected... certificates. A competent person shall visually inspect and test each space certified as “Safe for Workers” or...

  16. Staying Healthy and Safe at Work

    MedlinePlus

    ... The Prematurity Campaign About us Annual report Our work Community impact Global programs Research Need help? Frequently ... safe at work Staying healthy and safe at work E-mail to a friend Please fill in ...

  17. Characteristic overpressure-impulse-distance curves for vapour cloud explosions using the TNO Multi-Energy model.

    PubMed

    Díaz Alonso, Fernando; González Ferradás, Enrique; Sánchez Pérez, Juan Francisco; Miñana Aznar, Agustín; Ruiz Gimeno, José; Martínez Alonso, Jesús

    2006-09-21

    A number of models have been proposed to calculate overpressure and impulse from accidental industrial explosions. When the blast is produced by ignition of a vapour cloud, the TNO Multi-Energy model is widely used. From the curves given by this model, data are fitted to obtain equations showing the relationship between overpressure, impulse and distance. These equations, referred herein as characteristic curves, can be fitted by means of power equations, which depend on explosion energy and charge strength. Characteristic curves allow the determination of overpressure and impulse at each distance.

  18. 33 CFR 83.06 - Safe speed (Rule 6).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Safe speed (Rule 6). 83.06... Safe speed (Rule 6). Every vessel shall at all times proceed at a safe speed so that she can take... prevailing circumstances and conditions. In determining a safe speed the following factors shall be among...

  19. 33 CFR 83.06 - Safe speed (Rule 6).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Safe speed (Rule 6). 83.06... Safe speed (Rule 6). Every vessel shall at all times proceed at a safe speed so that she can take... prevailing circumstances and conditions. In determining a safe speed the following factors shall be among...

  20. Subalpine bumble bee foraging distances and densities in relation to flower availability.

    PubMed

    Elliott, Susan E

    2009-06-01

    Bees feed almost exclusively on nectar and pollen from flowers. However, little is known about how food availability limits bee populations, especially in high elevation areas. Foraging distances and relationships between forager densities and resource availability can provide insights into the potential for food limitation in mobile consumer populations. For example, if floral resources are limited, bee consumers should fly farther to forage, and they should be more abundant in areas with more flowers. I estimated subalpine bumble bee foraging distances by calculating forager recapture probabilities at increasing distances from eight marking locations. I measured forager and flower densities over the flowering season in six half-hectare plots. Because subalpine bumble bees have little time to build their colonies, they may forage over short distances and forager density may not be constrained by flower density. However, late in the season, when floral resources dwindle, foraging distances may increase, and there may be stronger relationships between forager and flower densities. Throughout the flowering season, marked bees were primarily found within 100 m (and never >1,000 m) from their original marking location, suggesting that they typically did not fly far to forage. Although the density of early season foraging queens increased with early-season flower density, the density of mid- and late-season workers and males did not vary with flower density. Short foraging distances and no relationships between mid- and late-season forager and flower densities suggest that high elevation bumble bees may have ample floral resources for colony growth reproduction.

  1. Avoidance of singularities in asymptotically safe Quantum Einstein Gravity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kofinas, Georgios; Zarikas, Vasilios; Department of Physics, Aristotle University of Thessaloniki,54124 Thessaloniki

    2015-10-30

    New general spherically symmetric solutions have been derived with a cosmological “constant” Λ as a source. This Λ term is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed point. The importance of these solutions comes from the fact that they may describe the near to the centre region of black hole spacetimes as this is modified by the Renormalization Group scaling behaviour of the fields. The consistent set of field equations which respect the Bianchi identities is derived and solved. One of the solutions (with conventional sign of temporal-radial metric components) ismore » timelike geodesically complete, and although there is still a curvature divergent origin, this is never approachable by an infalling massive particle which is reflected at a finite distance due to the repulsive origin. Another family of solutions (of both signatures) range from a finite radius outwards, they cannot be extended to the centre of spherical symmetry, and the curvature invariants are finite at the minimum radius.« less

  2. Avoidance of singularities in asymptotically safe Quantum Einstein Gravity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kofinas, Georgios; Zarikas, Vasilios, E-mail: gkofinas@aegean.gr, E-mail: vzarikas@teilam.gr

    2015-10-01

    New general spherically symmetric solutions have been derived with a cosmological ''constant'' Λ as a source. This Λ term is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed point. The importance of these solutions comes from the fact that they may describe the near to the centre region of black hole spacetimes as this is modified by the Renormalization Group scaling behaviour of the fields. The consistent set of field equations which respect the Bianchi identities is derived and solved. One of the solutions (with conventional sign of temporal-radial metric components) ismore » timelike geodesically complete, and although there is still a curvature divergent origin, this is never approachable by an infalling massive particle which is reflected at a finite distance due to the repulsive origin. Another family of solutions (of both signatures) range from a finite radius outwards, they cannot be extended to the centre of spherical symmetry, and the curvature invariants are finite at the minimum radius.« less

  3. On Calculating the Zero-Gravity Surface Figure of a Mirror

    NASA Technical Reports Server (NTRS)

    Bloemhof, Eric E.

    2010-01-01

    An analysis of the classical method of calculating the zero-gravity surface figure of a mirror from surface-figure measurements in the presence of gravity has led to improved understanding of conditions under which the calculations are valid. In this method, one measures the surface figure in two or more gravity- reversed configurations, then calculates the zero-gravity surface figure as the average of the surface figures determined from these measurements. It is now understood that gravity reversal is not, by itself, sufficient to ensure validity of the calculations: It is also necessary to reverse mounting forces, for which purpose one must ensure that mountingfixture/ mirror contacts are located either at the same places or else sufficiently close to the same places in both gravity-reversed configurations. It is usually not practical to locate the contacts at the same places, raising the question of how close is sufficiently close. The criterion for sufficient closeness is embodied in the St. Venant principle, which, in the present context, translates to a requirement that the distance between corresponding gravity-reversed mounting positions be small in comparison to their distances to the optical surface of the mirror. The necessity of reversing mount forces is apparent in the behavior of the equations familiar from finite element analysis (FEA) that govern deformation of the mirror.

  4. Conceptual Design of the Chornobyl New Safe Confinement - an Overview

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kulishenko, Valery N.; Hogg, Charles; Schmieman, Eric A.

    2006-05-01

    The Object Shelter, constructed over the Chornobyl nuclear power plant that was destroyed by a 1986 accident, is at risk of collapse. The Consortium of Bechtel, Electricité De France, and Battelle, in cooperation with subcontractor КСК, recently completed the conceptual design for a New Safe Confinement (NSC) building to reduce Shelter corrosion, to mitigate the consequences of potential collapse, and to enable the safe deconstruction of unstable structures. The arch-shaped NSC will be constructed at a distance from the Shelter to minimize radiation exposure to construction workers, and then slid into place over the Shelter. After sliding, cranes and othermore » tools inside the NSC will be remotely operated for deconstruction of the Shelter. The NSC is designed for a 100-year life. Bechtel designed the arch structure and was responsible for project management functions. Electricité De France designed the foundations and designed deconstruction of the Object Shelter unstable elements. Battelle performed safety analyses and environmental impact assessment. КСК (a consortium of КIЕЛ [KIEP], НДIБК [NIISK], and МНТЦ [ISTC]), as a working partner in all aspects of the design and analysis processes, was the Ukrainian licensed engineer for conceptual design. The design is currently being reviewed by Ukrainian regulatory authorities. An open international tender for detailed design and construction is anticipated to be announced by the European Bank for Reconstruction and Development in December, 2003, with two-stage bid evaluation beginning in April, 2004.« less

  5. Safe medication management in specialized home healthcare - an observational study.

    PubMed

    Lindblad, Marléne; Flink, Maria; Ekstedt, Mirjam

    2017-08-24

    Medication management is a complex, error-prone process. The aim of this study was to explore what constitutes the complexity of the medication management process (MMP) in specialized home healthcare and how healthcare professionals handle this complexity. The study is theoretically based in resilience engineering. Data were collected during the MMP at three specialized home healthcare units in Sweden using two strategies: observation of workplaces and shadowing RNs in everyday work, including interviews. Transcribed material was analysed using grounded theory. The MMP in home healthcare was dynamic and complex with unclear boundaries of responsibilities, inadequate information systems and fluctuating work conditions. Healthcare professionals adapted their everyday clinical work by sharing responsibility and simultaneously being authoritative and preserving patients' active participation, autonomy and integrity. To promote a safe MMP, healthcare professionals constantly re-prioritized goals, handled gaps in communication and information transmission at a distance by creating new bridging solutions. Trade-offs and workarounds were necessary elements, but also posed a threat to patient safety, as these interim solutions were not systematically evaluated or devised learning strategies. To manage a safe medication process in home healthcare, healthcare professionals need to adapt to fluctuating conditions and create bridging strategies through multiple parallel activities distributed over time, space and actors. The healthcare professionals' strategies could be integrated in continuous learning, while preserving boundaries of safety, instead of being more or less interim solutions. Patients' and family caregivers' as active partners in the MMP may be an underestimated resource for a resilient home healthcare.

  6. Why GPS makes distances bigger than they are

    PubMed Central

    Ranacher, Peter; Brunauer, Richard; Trutschnig, Wolfgang; Van der Spek, Stefan; Reich, Siegfried

    2016-01-01

    ABSTRACT Global navigation satellite systems such as the Global Positioning System (GPS) is one of the most important sensors for movement analysis. GPS is widely used to record the trajectories of vehicles, animals and human beings. However, all GPS movement data are affected by both measurement and interpolation errors. In this article we show that measurement error causes a systematic bias in distances recorded with a GPS; the distance between two points recorded with a GPS is – on average – bigger than the true distance between these points. This systematic ‘overestimation of distance’ becomes relevant if the influence of interpolation error can be neglected, which in practice is the case for movement sampled at high frequencies. We provide a mathematical explanation of this phenomenon and illustrate that it functionally depends on the autocorrelation of GPS measurement error (C). We argue that C can be interpreted as a quality measure for movement data recorded with a GPS. If there is a strong autocorrelation between any two consecutive position estimates, they have very similar error. This error cancels out when average speed, distance or direction is calculated along the trajectory. Based on our theoretical findings we introduce a novel approach to determine C in real-world GPS movement data sampled at high frequencies. We apply our approach to pedestrian trajectories and car trajectories. We found that the measurement error in the data was strongly spatially and temporally autocorrelated and give a quality estimate of the data. Most importantly, our findings are not limited to GPS alone. The systematic bias and its implications are bound to occur in any movement data collected with absolute positioning if interpolation error can be neglected. PMID:27019610

  7. Realistic Testing of the Safe Affordable Fission Engine (SAFE-100) Thermal Simulator Using Fiber Bragg Gratings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stinson-Bagby, Kelly L.; Fielder, Robert S.; Van Dyke, Melissa K.

    2004-02-04

    The motivation for the reported research was to support NASA space nuclear power initiatives through the development of advanced fiber optic sensors for space-based nuclear power applications. Distributed high temperature measurements were made with 20 FBG temperature sensors installed in the SAFE-100 thermal simulator at the NASA Marshal Space Flight Center. Experiments were performed at temperatures approaching 800 deg. C and 1150 deg. C for characterization studies of the SAFE-100 core. Temperature profiles were successfully generated for the core during temperature increases and decreases. Related tests in the SAFE-100 successfully provided strain measurement data.

  8. Calculators, Graphs, Gestures and the Production of Meaning

    ERIC Educational Resources Information Center

    Radford, Luis; Demers, Serge; Guzman, Jose; Cerulli, Michele

    2003-01-01

    In this paper we report an analysis of a teaching sequence in which Grade 11 students were asked to produce some graphs corresponding to the relationship between time and distance of a cylinder moving up and down an inclined plane. The students were also asked to carry out the experience using a TI 83+ graphic calculator equipped with a sensor,…

  9. Does improved access to water supply by rural households enhance the concept of safe water at the point of use? A case study from deep rural South Africa.

    PubMed

    Jagals, P

    2006-01-01

    The concept of safe water is defined by three principles: the health-related quality must be suitable, the supply/source must be accessible and the water must constantly be available in quantities sufficient for the intended use. If any one (or more) of these three elements is missing from a water services improvement programme, providing safe water is not successfully achieved. A study in a deep rural area in South Africa showed that providing small communities, using untreated river water as their only water source, with good quality water through a piped distribution system and accessible at communal taps did not fall within our parameters of safe water. The parameters for measuring the three principles were: absence of Escherichia coli in drinking water samples; accessibility by improving tap distances to within 200 m from each household; availability by assessing whether households have at least 25 L per person per day. Results show that although E. coli levels were reduced significantly, households were still consuming water with E. coli numbers at non-compliant levels. Access (distance) was improved from an average of 750 m from households to river source to an average of 120 m to new on-tap source points. This did not result in significant increases in household quantities, which on average remained around 18 L per person per day.

  10. Making Distance Visible: Assembling Nearness in an Online Distance Learning Programme

    ERIC Educational Resources Information Center

    Ross, Jen; Gallagher, Michael Sean; Macleod, Hamish

    2013-01-01

    Online distance learners are in a particularly complex relationship with the educational institutions they belong to (Bayne, Gallagher, & Lamb, 2012). For part-time distance students, arrivals and departures can be multiple and invisible as students take courses, take breaks, move into independent study phases of a programme, find work or…

  11. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe...

  12. 75 FR 1734 - Children’s Online Privacy Protection Rule Safe Harbor Proposed Self-Regulatory Guidelines; i-SAFE...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ...The Federal Trade Commission publishes this notice and request for public comment concerning proposed self-regulatory guidelines submitted by i-SAFE, Inc. under the safe harbor provision of the Children's Online Privacy Protection Rule.

  13. Spatial Interpolation of Fine Particulate Matter Concentrations Using the Shortest Wind-Field Path Distance

    PubMed Central

    Li, Longxiang; Gong, Jianhua; Zhou, Jieping

    2014-01-01

    Effective assessments of air-pollution exposure depend on the ability to accurately predict pollutant concentrations at unmonitored locations, which can be achieved through spatial interpolation. However, most interpolation approaches currently in use are based on the Euclidean distance, which cannot account for the complex nonlinear features displayed by air-pollution distributions in the wind-field. In this study, an interpolation method based on the shortest path distance is developed to characterize the impact of complex urban wind-field on the distribution of the particulate matter concentration. In this method, the wind-field is incorporated by first interpolating the observed wind-field from a meteorological-station network, then using this continuous wind-field to construct a cost surface based on Gaussian dispersion model and calculating the shortest wind-field path distances between locations, and finally replacing the Euclidean distances typically used in Inverse Distance Weighting (IDW) with the shortest wind-field path distances. This proposed methodology is used to generate daily and hourly estimation surfaces for the particulate matter concentration in the urban area of Beijing in May 2013. This study demonstrates that wind-fields can be incorporated into an interpolation framework using the shortest wind-field path distance, which leads to a remarkable improvement in both the prediction accuracy and the visual reproduction of the wind-flow effect, both of which are of great importance for the assessment of the effects of pollutants on human health. PMID:24798197

  14. Spatial interpolation of fine particulate matter concentrations using the shortest wind-field path distance.

    PubMed

    Li, Longxiang; Gong, Jianhua; Zhou, Jieping

    2014-01-01

    Effective assessments of air-pollution exposure depend on the ability to accurately predict pollutant concentrations at unmonitored locations, which can be achieved through spatial interpolation. However, most interpolation approaches currently in use are based on the Euclidean distance, which cannot account for the complex nonlinear features displayed by air-pollution distributions in the wind-field. In this study, an interpolation method based on the shortest path distance is developed to characterize the impact of complex urban wind-field on the distribution of the particulate matter concentration. In this method, the wind-field is incorporated by first interpolating the observed wind-field from a meteorological-station network, then using this continuous wind-field to construct a cost surface based on Gaussian dispersion model and calculating the shortest wind-field path distances between locations, and finally replacing the Euclidean distances typically used in Inverse Distance Weighting (IDW) with the shortest wind-field path distances. This proposed methodology is used to generate daily and hourly estimation surfaces for the particulate matter concentration in the urban area of Beijing in May 2013. This study demonstrates that wind-fields can be incorporated into an interpolation framework using the shortest wind-field path distance, which leads to a remarkable improvement in both the prediction accuracy and the visual reproduction of the wind-flow effect, both of which are of great importance for the assessment of the effects of pollutants on human health.

  15. A new single-particle basis for nuclear many-body calculations

    NASA Astrophysics Data System (ADS)

    Puddu, G.

    2017-10-01

    Predominantly, harmonic oscillator single-particle wave functions are the preferred choice for a basis in ab initio nuclear many-body calculations. These wave-functions, although very convenient in order to evaluate the matrix elements of the interaction in the laboratory frame, have too fast a fall-off at large distances. In the past, as an alternative to the harmonic oscillator, other single-particle wave functions have been proposed. In this work, we propose a new single-particle basis, directly linked to nucleon-nucleon interaction. This new basis is orthonormal and complete, has the proper asymptotic behavior at large distances and does not contain the continuum which would pose severe convergence problems in nuclear many body calculations. We consider the newly proposed NNLO-opt nucleon-nucleon interaction, without any renormalization. We show that, unlike other bases, this single-particle representation has a computational cost similar to the harmonic oscillator basis with the same space truncation and it gives lower energies for 6He and 6Li.

  16. Curiosity's Autonomous Surface Safing Behavior Design

    NASA Technical Reports Server (NTRS)

    Neilson, Tracy A.; Manning, Robert M.

    2013-01-01

    The safing routines on all robotic deep-space vehicles are designed to put the vehicle in a power and thermally safe configuration, enabling communication with the mission operators on Earth. Achieving this goal is made a little more difficult on Curiosity because the power requirements for the core avionics and the telecommunication equipment exceed the capability of the single power source, the Multi-Mission Radioisotope Thermoelectric Generator. This drove the system design to create an operational mode, called "sleep mode", where the vehicle turns off most of the loads in order to charge the two Li-ion batteries. The system must keep the vehicle safe from over-heat and under-heat conditions, battery cell failures, under-voltage conditions, and clock failures, both while the computer is running and while the system is sleeping. The other goal of a safing routine is to communicate. On most spacecraft, this simply involves turning on the receiver and transmitter continuously. For Curiosity, Earth is above the horizon only a part of the day for direct communication to the Earth, and the orbiter overpass opportunities only occur a few times a day. The design must robustly place the Rover in a communicable condition at the correct time. This paper discusses Curiosity's autonomous safing behavior and describes how the vehicle remains power and thermally safe while sleeping, as well as a description of how the Rover communicates with the orbiters and Earth at specific times.

  17. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  18. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  19. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Safe water marks. 62.27 Section... UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is navigable water all around the mark. They are often used to indicate...

  20. Acceleration of intensity-modulated radiotherapy dose calculation by importance sampling of the calculation matrices.

    PubMed

    Thieke, Christian; Nill, Simeon; Oelfke, Uwe; Bortfeld, Thomas

    2002-05-01

    In inverse planning for intensity-modulated radiotherapy, the dose calculation is a crucial element limiting both the maximum achievable plan quality and the speed of the optimization process. One way to integrate accurate dose calculation algorithms into inverse planning is to precalculate the dose contribution of each beam element to each voxel for unit fluence. These precalculated values are stored in a big dose calculation matrix. Then the dose calculation during the iterative optimization process consists merely of matrix look-up and multiplication with the actual fluence values. However, because the dose calculation matrix can become very large, this ansatz requires a lot of computer memory and is still very time consuming, making it not practical for clinical routine without further modifications. In this work we present a new method to significantly reduce the number of entries in the dose calculation matrix. The method utilizes the fact that a photon pencil beam has a rapid radial dose falloff, and has very small dose values for the most part. In this low-dose part of the pencil beam, the dose contribution to a voxel is only integrated into the dose calculation matrix with a certain probability. Normalization with the reciprocal of this probability preserves the total energy, even though many matrix elements are omitted. Three probability distributions were tested to find the most accurate one for a given memory size. The sampling method is compared with the use of a fully filled matrix and with the well-known method of just cutting off the pencil beam at a certain lateral distance. A clinical example of a head and neck case is presented. It turns out that a sampled dose calculation matrix with only 1/3 of the entries of the fully filled matrix does not sacrifice the quality of the resulting plans, whereby the cutoff method results in a suboptimal treatment plan.

  1. [Study of the effect of heat source separation distance on plasma physical properties in laser-pulsed GMAW hybrid welding based on spectral diagnosis technique].

    PubMed

    Liao, Wei; Hua, Xue-Ming; Zhang, Wang; Li, Fang

    2014-05-01

    In the present paper, the authors calculated the plasma's peak electron temperatures under different heat source separation distance in laser- pulse GMAW hybrid welding based on Boltzmann spectrometry. Plasma's peak electron densities under the corresponding conditions were also calculated by using the Stark width of the plasma spectrum. Combined with high-speed photography, the effect of heat source separation distance on electron temperature and electron density was studied. The results show that with the increase in heat source separation distance, the electron temperatures and electron densities of laser plasma did not changed significantly. However, the electron temperatures of are plasma decreased, and the electron densities of are plasma first increased and then decreased.

  2. Theoretical Principles of Distance Education.

    ERIC Educational Resources Information Center

    Keegan, Desmond, Ed.

    This book contains the following papers examining the didactic, academic, analytic, philosophical, and technological underpinnings of distance education: "Introduction"; "Quality and Access in Distance Education: Theoretical Considerations" (D. Randy Garrison); "Theory of Transactional Distance" (Michael G. Moore);…

  3. The Distance to M51

    NASA Astrophysics Data System (ADS)

    McQuinn, Kristen. B. W.; Skillman, Evan D.; Dolphin, Andrew E.; Berg, Danielle; Kennicutt, Robert

    2016-07-01

    Great investments of observing time have been dedicated to the study of nearby spiral galaxies with diverse goals ranging from understanding the star formation process to characterizing their dark matter distributions. Accurate distances are fundamental to interpreting observations of these galaxies, yet many of the best studied nearby galaxies have distances based on methods with relatively large uncertainties. We have started a program to derive accurate distances to these galaxies. Here we measure the distance to M51—the Whirlpool galaxy—from newly obtained Hubble Space Telescope optical imaging using the tip of the red giant branch method. We measure the distance modulus to be 8.58 ± 0.10 Mpc (statistical), corresponding to a distance modulus of 29.67 ± 0.02 mag. Our distance is an improvement over previous results as we use a well-calibrated, stable distance indicator, precision photometry in a optimally selected field of view, and a Bayesian Maximum Likelihood technique that reduces measurement uncertainties. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  4. Removing Hair Safely

    MedlinePlus

    ... For Consumers Home For Consumers Consumer Updates Removing Hair Safely Share Tweet Linkedin Pin it More sharing ... related to common methods of hair removal. Laser Hair Removal In this method, a laser destroys hair ...

  5. Distance learning in academic health education.

    PubMed

    Mattheos, N; Schittek, M; Attström, R; Lyon, H C

    2001-05-01

    Distance learning is an apparent alternative to traditional methods in education of health care professionals. Non-interactive distance learning, interactive courses and virtual learning environments exist as three different generations in distance learning, each with unique methodologies, strengths and potential. Different methodologies have been recommended for distance learning, varying from a didactic approach to a problem-based learning procedure. Accreditation, teamwork and personal contact between the tutors and the students during a course provided by distance learning are recommended as motivating factors in order to enhance the effectiveness of the learning. Numerous assessment methods for distance learning courses have been proposed. However, few studies report adequate tests for the effectiveness of the distance-learning environment. Available information indicates that distance learning may significantly decrease the cost of academic health education at all levels. Furthermore, such courses can provide education to students and professionals not accessible by traditional methods. Distance learning applications still lack the support of a solid theoretical framework and are only evaluated to a limited extent. Cases reported so far tend to present enthusiastic results, while more carefully-controlled studies suggest a cautious attitude towards distance learning. There is a vital need for research evidence to identify the factors of importance and variables involved in distance learning. The effectiveness of distance learning courses, especially in relation to traditional teaching methods, must therefore be further investigated.

  6. A fail-safe CMOS logic gate

    NASA Technical Reports Server (NTRS)

    Bobin, V.; Whitaker, S.

    1990-01-01

    This paper reports a design technique to make Complex CMOS Gates fail-safe for a class of faults. Two classes of faults are defined. The fail-safe design presented has limited fault-tolerance capability. Multiple faults are also covered.

  7. Safe mobility for older people notebook

    DOT National Transportation Integrated Search

    1999-04-01

    The Safe Mobility for Older People Notebook is a research product of the "Model Driver Screening and Evaluation Program" project sponsored by NHTSA, and is intended as a resource to support program initiatives promoting the safe mobility of older per...

  8. Learning a Mahalanobis Distance-Based Dynamic Time Warping Measure for Multivariate Time Series Classification.

    PubMed

    Mei, Jiangyuan; Liu, Meizhu; Wang, Yuan-Fang; Gao, Huijun

    2016-06-01

    Multivariate time series (MTS) datasets broadly exist in numerous fields, including health care, multimedia, finance, and biometrics. How to classify MTS accurately has become a hot research topic since it is an important element in many computer vision and pattern recognition applications. In this paper, we propose a Mahalanobis distance-based dynamic time warping (DTW) measure for MTS classification. The Mahalanobis distance builds an accurate relationship between each variable and its corresponding category. It is utilized to calculate the local distance between vectors in MTS. Then we use DTW to align those MTS which are out of synchronization or with different lengths. After that, how to learn an accurate Mahalanobis distance function becomes another key problem. This paper establishes a LogDet divergence-based metric learning with triplet constraint model which can learn Mahalanobis matrix with high precision and robustness. Furthermore, the proposed method is applied on nine MTS datasets selected from the University of California, Irvine machine learning repository and Robert T. Olszewski's homepage, and the results demonstrate the improved performance of the proposed approach.

  9. Estimating rupture distances without a rupture

    USGS Publications Warehouse

    Thompson, Eric M.; Worden, Charles

    2017-01-01

    Most ground motion prediction equations (GMPEs) require distances that are defined relative to a rupture model, such as the distance to the surface projection of the rupture (RJB) or the closest distance to the rupture plane (RRUP). There are a number of situations in which GMPEs are used where it is either necessary or advantageous to derive rupture distances from point-source distance metrics, such as hypocentral (RHYP) or epicentral (REPI) distance. For ShakeMap, it is necessary to provide an estimate of the shaking levels for events without rupture models, and before rupture models are available for events that eventually do have rupture models. In probabilistic seismic hazard analysis, it is often convenient to use point-source distances for gridded seismicity sources, particularly if a preferred orientation is unknown. This avoids the computationally cumbersome task of computing rupture-based distances for virtual rupture planes across all strikes and dips for each source. We derive average rupture distances conditioned on REPI, magnitude, and (optionally) back azimuth, for a variety of assumed seismological constraints. Additionally, we derive adjustment factors for GMPE standard deviations that reflect the added uncertainty in the ground motion estimation when point-source distances are used to estimate rupture distances.

  10. Heat Pipe Reactor Dynamic Response Tests: SAFE-100 Reactor Core Prototype

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.

    2005-01-01

    The SAFE-I00a test article at the NASA Marshall Space Flight Center was used to simulate a variety of potential reactor transients; the SAFEl00a is a resistively heated, stainless-steel heat-pipe (HP)-reactor core segment, coupled to a gas-flow heat exchanger (HX). For these transients the core power was controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. This type of non-nuclear test is expected to provide reasonable approximation of reactor transient behavior because reactivity feedback is very simple in a compact fast reactor (simple, negative, and relatively monotonic temperature feedback, caused mostly by thermal expansion) and calculations show there are no significant reactivity effects associated with fluid in the HP (the worth of the entire inventory of Na in the core is .SAFE-100 tests, the point kinetics model was based on core thermal expansion via deflection measurements. It was found that core deflection was a strung function of how the SAFE-100 modules were fabricated and assembled (in terms of straightness, gaps, and other tolerances). To remove the added variable of how this particular core expands as compared to a different concept, it was decided to use a temperature based feedback model (based on several thermocouples placed throughout the core).

  11. Distance geometry protocol to generate conformations of natural products to structurally interpret ion mobility-mass spectrometry collision cross sections.

    PubMed

    Stow, Sarah M; Goodwin, Cody R; Kliman, Michal; Bachmann, Brian O; McLean, John A; Lybrand, Terry P

    2014-12-04

    Ion mobility-mass spectrometry (IM-MS) allows the separation of ionized molecules based on their charge-to-surface area (IM) and mass-to-charge ratio (MS), respectively. The IM drift time data that is obtained is used to calculate the ion-neutral collision cross section (CCS) of the ionized molecule with the neutral drift gas, which is directly related to the ion conformation and hence molecular size and shape. Studying the conformational landscape of these ionized molecules computationally provides interpretation to delineate the potential structures that these CCS values could represent, or conversely, structural motifs not consistent with the IM data. A challenge in the IM-MS community is the ability to rapidly compute conformations to interpret natural product data, a class of molecules exhibiting a broad range of biological activity. The diversity of biological activity is, in part, related to the unique structural characteristics often observed for natural products. Contemporary approaches to structurally interpret IM-MS data for peptides and proteins typically utilize molecular dynamics (MD) simulations to sample conformational space. However, MD calculations are computationally expensive, they require a force field that accurately describes the molecule of interest, and there is no simple metric that indicates when sufficient conformational sampling has been achieved. Distance geometry is a computationally inexpensive approach that creates conformations based on sampling different pairwise distances between the atoms within the molecule and therefore does not require a force field. Progressively larger distance bounds can be used in distance geometry calculations, providing in principle a strategy to assess when all plausible conformations have been sampled. Our results suggest that distance geometry is a computationally efficient and potentially superior strategy for conformational analysis of natural products to interpret gas-phase CCS data.

  12. Distance Geometry Protocol to Generate Conformations of Natural Products to Structurally Interpret Ion Mobility-Mass Spectrometry Collision Cross Sections

    PubMed Central

    2015-01-01

    Ion mobility-mass spectrometry (IM-MS) allows the separation of ionized molecules based on their charge-to-surface area (IM) and mass-to-charge ratio (MS), respectively. The IM drift time data that is obtained is used to calculate the ion-neutral collision cross section (CCS) of the ionized molecule with the neutral drift gas, which is directly related to the ion conformation and hence molecular size and shape. Studying the conformational landscape of these ionized molecules computationally provides interpretation to delineate the potential structures that these CCS values could represent, or conversely, structural motifs not consistent with the IM data. A challenge in the IM-MS community is the ability to rapidly compute conformations to interpret natural product data, a class of molecules exhibiting a broad range of biological activity. The diversity of biological activity is, in part, related to the unique structural characteristics often observed for natural products. Contemporary approaches to structurally interpret IM-MS data for peptides and proteins typically utilize molecular dynamics (MD) simulations to sample conformational space. However, MD calculations are computationally expensive, they require a force field that accurately describes the molecule of interest, and there is no simple metric that indicates when sufficient conformational sampling has been achieved. Distance geometry is a computationally inexpensive approach that creates conformations based on sampling different pairwise distances between the atoms within the molecule and therefore does not require a force field. Progressively larger distance bounds can be used in distance geometry calculations, providing in principle a strategy to assess when all plausible conformations have been sampled. Our results suggest that distance geometry is a computationally efficient and potentially superior strategy for conformational analysis of natural products to interpret gas-phase CCS data. PMID:25360896

  13. Influence des interactions entre écrans de soutènement sur le calcul de la butée

    NASA Astrophysics Data System (ADS)

    Magnan, Jean-Pierre; Meyer, Grégory

    2018-05-01

    La mobilisation de la butée devant un écran implique un volume de sol important, sur une distance plus grande que la fiche et qui dépend des paramètres du calcul. L'article passe en revue les méthodes de calcul utilisées pour évaluer la butée, en insistant sur la distance nécessaire au libre développement du mécanisme de butée. Il évalue ensuite de différentes façons l'effet de l'interaction entre deux écrans placés face à face de part et d'autre d'une excavation. La méthode recommandée pour calculer la butée mobilisable consiste à faire un calcul en éléments finis avec des valeurs réduites des paramètres de résistance au cisaillement dans la zone où se développera la butée. Cette démarche permet de déterminer des facteurs correctifs à appliquer au calcul de la butée d'un écran isolé en fonction du rapport de la distance entre écrans à leur fiche.

  14. 33 CFR 62.27 - Safe water marks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Safe water marks. 62.27 Section 62.27 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION UNITED STATES AIDS TO NAVIGATION SYSTEM The U.S. Aids to Navigation System § 62.27 Safe water marks. Safe water marks indicate that there is...

  15. Developing Safe Schools Partnerships with Law Enforcement

    ERIC Educational Resources Information Center

    Rosiak, John

    2009-01-01

    Safe schools are the concern of communities throughout the world. If a school is safe, and if children feel safe, students "are better able to learn. But what are the steps to make" this happen? First, it is important to understand the problem: What are the threats to school safety? These include crime-related behaviors that find their way to…

  16. General practice cooperatives: long waiting times for home visits due to long distances?

    PubMed Central

    Giesen, Paul; van Lin, Nieke; Mokkink, Henk; van den Bosch, Wil; Grol, Richard

    2007-01-01

    Background The introduction of large-scale out-of-hours GP cooperatives has led to questions about increased distances between the GP cooperatives and the homes of patients and the increasing waiting times for home visits in urgent cases. We studied the relationship between the patient's waiting time for a home visit and the distance to the GP cooperative. Further, we investigated if other factors (traffic intensity, home visit intensity, time of day, and degree of urgency) influenced waiting times. Methods Cross-sectional study at four GP cooperatives. We used variance analysis to calculate waiting times for various categories of traffic intensity, home visit intensity, time of day, and degree of urgency. We used multiple logistic regression analysis to calculate to what degree these factors affected the ability to meet targets in urgent cases. Results The average waiting time for 5827 consultations was 30.5 min. Traffic intensity, home visit intensity, time of day and urgency of the complaint all seemed to affect waiting times significantly. A total of 88.7% of all patients were seen within 1 hour. In the case of life-threatening complaints (U1), 68.8% of the patients were seen within 15 min, and 95.6% of those with acute complaints (U2) were seen within 1 hour. For patients with life-threatening complaints (U1) the percentage of visits that met the time target of 15 minuts decreased from 86.5% (less than 2.5 km) to 16.7% (equals or more than 20 km). Discussion and conclusion Although home visits waiting times increase with increasing distance from the GP cooperative, it appears that traffic intensity, home visit intensity, and urgency also influence waiting times. For patients with life-threatening complaints waiting times increase sharply with the distance. PMID:17295925

  17. General practice cooperatives: long waiting times for home visits due to long distances?

    PubMed

    Giesen, Paul; van Lin, Nieke; Mokkink, Henk; van den Bosch, Wil; Grol, Richard

    2007-02-12

    The introduction of large-scale out-of-hours GP cooperatives has led to questions about increased distances between the GP cooperatives and the homes of patients and the increasing waiting times for home visits in urgent cases. We studied the relationship between the patient's waiting time for a home visit and the distance to the GP cooperative. Further, we investigated if other factors (traffic intensity, home visit intensity, time of day, and degree of urgency) influenced waiting times. Cross-sectional study at four GP cooperatives. We used variance analysis to calculate waiting times for various categories of traffic intensity, home visit intensity, time of day, and degree of urgency. We used multiple logistic regression analysis to calculate to what degree these factors affected the ability to meet targets in urgent cases. The average waiting time for 5827 consultations was 30.5 min. Traffic intensity, home visit intensity, time of day and urgency of the complaint all seemed to affect waiting times significantly. A total of 88.7% of all patients were seen within 1 hour. In the case of life-threatening complaints (U1), 68.8% of the patients were seen within 15 min, and 95.6% of those with acute complaints (U2) were seen within 1 hour. For patients with life-threatening complaints (U1) the percentage of visits that met the time target of 15 minutes decreased from 86.5% (less than 2.5 km) to 16.7% (equals or more than 20 km). Although home visits waiting times increase with increasing distance from the GP cooperative, it appears that traffic intensity, home visit intensity, and urgency also influence waiting times. For patients with life-threatening complaints waiting times increase sharply with the distance.

  18. GIS modelling of seismic vulnerability of residential fabrics considering geotechnical, structural, social and physical distance indicators in Tehran city using multi-criteria decision-making (MCDM) techniques

    NASA Astrophysics Data System (ADS)

    Rezaie, F.; Panahi, M.

    2014-09-01

    The main issue in determining the seismic vulnerability is having a comprehensive view to all probable damages related to earthquake occurrence. Therefore, taking factors such as peak ground acceleration (PGA) in the time of earthquake occurrence, the type of structures, population distribution among different age groups, level of education, the physical distance to a hospitals (or medical care centers), etc. into account and categorized under four indicators of geotechnical, structural, social and physical distance to needed facilities and distance from dangerous ones will provide us with a better and more exact outcome. To this end in this paper using analytic hierarchy process (AHP), the amount of importance of criteria or alternatives are determined and using geographical information system (GIS), the vulnerability of Tehran metropolitan as a result of an earthquake, is studied. This study focuses on the fact that Tehran is surrounded by three active and major faults of the Mosha, North Tehran and Rey. In order to comprehensively determine the vulnerability, three scenarios are developed. In each scenario, seismic vulnerability of different areas in Tehran city is analysed and classified into four levels including high, medium, low and safe. The results show that regarding seismic vulnerability, the faults of Mosha, North Tehran and Rey respectively make 6, 16 and 10% of Tehran area highly vulnerable and also 34, 14 and 27% are safe.

  19. Absolute Ages and Distances of 22 GCs Using Monte Carlo Main-sequence Fitting

    NASA Astrophysics Data System (ADS)

    O'Malley, Erin M.; Gilligan, Christina; Chaboyer, Brian

    2017-04-01

    The recent Gaia Data Release 1 of stellar parallaxes provides ample opportunity to find metal-poor main-sequence stars with precise parallaxes. We select 21 such stars with parallax uncertainties better than σ π /π ≤ 0.10 and accurate abundance determinations suitable for testing metal-poor stellar evolution models and determining the distance to Galactic globular clusters (GCs). A Monte Carlo analysis was used, taking into account uncertainties in the model construction parameters, to generate stellar models and isochrones to fit to the calibration stars. The isochrones that fit the calibration stars best were then used to determine the distances and ages of 22 GCs with metallicities ranging from -2.4 dex to -0.7 dex. We find distances with an average uncertainty of 0.15 mag and absolute ages ranging from 10.8 to 13.6 Gyr with an average uncertainty of 1.6 Gyr. Using literature proper motion data, we calculate orbits for the clusters, finding six that reside within the Galactic disk/bulge, while the rest are considered halo clusters. We find no strong evidence for a relationship between age and Galactocentric distance, but we do find a decreasing age-[Fe/H] relation.

  20. Assessing the influence of geographic distance in parasite communities of an exotic lizard.

    PubMed

    Bezerra, Castiele Holanda; Pinheiro, Luan Tavares; de Melo, Gabriela Cavalcante; Zanchi-Silva, Djan; Queiroz, Murilo de Souza; dos Anjos, Luciano Alves; Harris, David James; Borges-Nojosa, Diva Maria

    2016-01-01

    The decay of similarity between biological communities with increasing geographical distance is a well-established pattern in ecology, but there are more complex factors acting on host population connections that influence this association for parasite communities, such as parasites' colonization ability and degree of connectivity between host populations. Here we aim to determine the helminth communities associated with different populations of the host lizard Hemidactylus mabouia, testing if the similarity of parasite communities decreases as the distance between them increases. For this, we collected samples of lizard populations in seven sites from Northeastern coast of Brazil and identified parasite species of helminths and pentastomids in each host, calculated the Sørensen indices of presence/absence and abundance of each pair of communities and related them to the geographical distance. We did not find a relationship of decaying similarity with increasing distance between the parasite communities of the host populations. This can be explained by factors such as the characteristics of the contact between the host populations, and by modes of transmission of most parasite species. Furthermore, it may be related to the exotic nature of the host in Brazil so that parasite communities have not reached equilibrium.

  1. Euclidean commute time distance embedding and its application to spectral anomaly detection

    NASA Astrophysics Data System (ADS)

    Albano, James A.; Messinger, David W.

    2012-06-01

    Spectral image analysis problems often begin by performing a preprocessing step composed of applying a transformation that generates an alternative representation of the spectral data. In this paper, a transformation based on a Markov-chain model of a random walk on a graph is introduced. More precisely, we quantify the random walk using a quantity known as the average commute time distance and find a nonlinear transformation that embeds the nodes of a graph in a Euclidean space where the separation between them is equal to the square root of this quantity. This has been referred to as the Commute Time Distance (CTD) transformation and it has the important characteristic of increasing when the number of paths between two nodes decreases and/or the lengths of those paths increase. Remarkably, a closed form solution exists for computing the average commute time distance that avoids running an iterative process and is found by simply performing an eigendecomposition on the graph Laplacian matrix. Contained in this paper is a discussion of the particular graph constructed on the spectral data for which the commute time distance is then calculated from, an introduction of some important properties of the graph Laplacian matrix, and a subspace projection that approximately preserves the maximal variance of the square root commute time distance. Finally, RX anomaly detection and Topological Anomaly Detection (TAD) algorithms will be applied to the CTD subspace followed by a discussion of their results.

  2. Safe haven laws as crime control theater.

    PubMed

    Hammond, Michelle; Miller, Monica K; Griffin, Timothy

    2010-07-01

    This article examines safe haven laws, which allow parents to legally abandon their infants. The main objective is to determine whether safe haven laws fit the criteria of crime control theater, a term used to describe public policies that produce the appearance, but not the effect, of crime control, and as such are essentially socially constructed "solutions" to socially constructed crime "problems." The analysis will apply the principles of crime control theater to safe haven laws. Specifically, the term crime control theater applies to laws that are reactionary responses to perceived criminal threats and are often widely supported as a way to address the crime in question. Such laws are attractive because they appeal to mythic narratives (i.e., saving an innocent child from a predator); however they are likely ineffective due to the complexity of the crime. These laws can have deleterious effects when policymakers make false claims of success and stunt public discourse (e.g., drawing attention away from more frequent and preventable crimes). This analysis applies these criteria to safe haven laws to determine whether such laws can be classified as crime control theater. Many qualities inherent to crime control theater are present in safe haven laws. For example, the laws are highly publicized, their intentions lack moral ambiguity, rare cases of success legitimize law enforcement and other agencies, and they appeal to the public sense of responsibility in preventing crime. Yet the goal of saving infant lives may be unattainable. These qualities make the effectiveness of the laws questionable and suggest they may be counterproductive. This analysis determined that safe haven laws are socially constructed solutions to the socially constructed problem of child abandonment. Safe haven laws are appropriately classified as crime control theater. It is imperative that further research be conducted to examine the effectiveness and collateral effects of safe haven laws

  3. Designing mark-recapture studies to reduce effects of distance weighting on movement distance distributions of stream fishes

    USGS Publications Warehouse

    Albanese, B.; Angermeier, P.L.; Gowan, C.

    2003-01-01

    Mark-recapture studies generate biased, or distance-weighted, movement data because short distances are sampled more frequently than long distances. Using models and field data, we determined how study design affects distance weighting and the movement distributions of stream fishes. We first modeled distance weighting as a function of recapture section length in an unbranching stream. The addition of an unsampled tributary to one of these models substantially increased distance weighting by decreasing the percentage of upstream distances that were sampled. Similarly, the presence of multiple tributaries in the field study resulted in severe bias. However, increasing recapture section length strongly affected distance weighting in both the model and the field study, producing a zone where the number of fish moving could be estimated with little bias. Subsampled data from the field study indicated that longer median (three of three species) and maximum distances (two of three species) can be detected by increasing the length of the recapture section. The effect was extreme for bluehead chub Nocomis leptocephalus, a highly mobile species, which exhibited a longer median distance (133 m versus 60 m), a longer maximum distance (1,144 m versus 708 m), and a distance distribution that differed in shape when the full (4,123-m recapture section) and subsampled (1,978-m recapture section) data sets were compared. Correction factors that adjust the observed number of movements to undersampled distances upwards and those to oversampled distances downwards could not mitigate the distance weighting imposed by the shorter recapture section. Future studies should identify the spatial scale over which movements can be accurately measured before data are collected. Increasing recapture section length a priori is far superior to using post hoc correction factors to reduce the influence of distance weighting on observed distributions. Implementing these strategies will be especially

  4. Safe Sleep Practices of Kansas Birthing Hospitals

    PubMed Central

    Ahlers-Schmidt, Carolyn R.; Schunn, Christy; Sage, Cherie; Engel, Matthew; Benton, Mary

    2018-01-01

    Background Sleep-related death is tied with congenital anomalies as the leading cause of infant mortality in Kansas, and external risk factors are present in 83% of these deaths. Hospitals can impact caregiver intentions to follow risk-reduction strategies. This project assessed the current practices and policies of Kansas hospitals with regard to safe sleep. Methods A cross-sectional survey of existing safe sleep practices and policies in Kansas hospitals was performed. Hospitals were categorized based on reported delivery volume and data were compared across hospital sizes. Results Thirty-one of 73 (42%) contacted hospitals responded. Individual survey respondents represented various hospital departments including newborn/well-baby (68%), neonatal intensive care unit (3%) and other non-nursery departments or administration (29%). Fifty-eight percent of respondents reported staff were trained on infant safe sleep; 44% of these held trainings annually. High volume hospitals tended to have more annual training than low or mid volume birth hospitals. Thirty-nine percent reported a safe sleep policy, though most of these (67%) reported never auditing compliance. The top barrier to safe sleep education, regardless of delivery volume, was conflicting patient and family member beliefs. Conclusions Hospital promotion of infant safe sleep is being conducted in Kansas to varying degrees. High and mid volume birth hospitals may need to work more on formal auditing of safe sleep practices, while low volume hospitals may need more staff training. Low volume hospitals also may benefit from access to additional caregiver education materials. Finally, it is important to note hospitals should not be solely responsible for safe sleep education. PMID:29844848

  5. Using Medications Safely

    MedlinePlus

    ... health systems play an important role in preventing medication errors. To make sure you use medicines safely and effectively, ASHP recommends that you: Keep a list of all medications that you take (prescribed drugs, nonprescription medicines, herbal ...

  6. Managing Time, Workload and Costs in Distance Education: Findings from a Literature Review of "Distances et Médiations des Savoirs" (Formerly "Distances et Savoirs")

    ERIC Educational Resources Information Center

    Moeglin, Pierre; Vidal, Martine

    2015-01-01

    The purpose of this review, spanning over 12 years of publication of "Distances et Médiations des Savoirs" ("DMS"), formerly "Distance et Savoirs" ("DMS") (2003-2014), is guided by the question why and how French-speaking researchers addressed the issues of time, workload and costs in distance learning, and…

  7. Distance Education in the Health Sciences. Readings in Distance Education, Number 8.

    ERIC Educational Resources Information Center

    Moore, Michael G. Ed.; Savrock, Joseph T., Ed.

    This document contains 17 papers on distance education in the health sciences. The following papers are included: "Preface: Distance Education in the Health Professions: A Collection of Research" (Michael G. Moore); "A Historical Overview of Telecommunications in the Health Care Industry" (Joseph S. Anderson); "Distance…

  8. Infrasound wave propagation over near-regional and tele-infrasonic distances

    NASA Astrophysics Data System (ADS)

    McKenna, Sara Mihan House

    2005-11-01

    Infrasound research is experiencing a renaissance due to advances in acoustic propagation calculations and a deeper understanding of the atmosphere. Uniquely combining observed data and propagation modeling, the three papers presented here quantify the effects of the atmosphere on propagation from a variety of sources at distances from less than 100 km (near-regional distances) to nearly 600 km (tele-infrasonic distances) for sources on the surface and at altitude (63 km). Paper one analyzes infrasound signals recorded at the CHNAR seismo-acoustic array. These sources are predominantly on the surface, result from human activity and occur closer than 250 km away. Propagation for these near-regional distances depends on tropospheric weather patterns and temporally varying, low-altitude ducts. To predict the observed arrivals local meteorological data is necessary; MSIS/HWM (Mass Spectrometer Incoherent Scatter/Horizontal Wind Model) and NRL-G2S (Naval Research Laboratory Ground To Space) did not predict the observed arrivals. Paper two is the first time a waveform from an explosion at height has ever been reproduced; the recorded waveform was from the break-up of the space shuttle Columbia. For the tele-infrasonic normal mode modeling, MSIS/HWM and NRL-G2S yielded identical waveform results. Paper three looks at the tele-infrasonic path between an iron mine in Minnesota and an infrasound array in Manitoba, Canada. Over a four month period, the IS-10 infrasound array provided infrasound data to compare to archived blast statistics. NRL-G2S better reproduced the observed arrival travel times than MSIS/HWM; whether or not arrivals were observed depended on the noise field at the infrasound array. For any distance range or source height, accurate atmospheric parameters from the corresponding propagation paths are necessary to predict observed infrasound.

  9. Sexual practices, myths and misconceptions among long distance truck drivers in North India.

    PubMed

    Sawal, N; Hans, G D R; Verma, G

    2016-07-01

    Long distance truck drivers and helpers constitute a high risk group for human immunodeficiency virus /acquired immune deficiency syndrome (HIV/AIDS). Despite increasing awareness of HIV/AIDS and safe sex practices, they still have a high incidence of new cases of HIV. This study carried out at an ART (anti-retroviral treatment) centre in North India aimed to evaluate the sexual myths and misconceptions prevalent among long distance drivers and helpers. This was a retrospective study carried out at apex ART centre. Data were collected retrospectively from ART records of 129 long distance Truck drivers and 68 helpers. Details of socio-demographic characteristics, contact with commercial sex workers (CSW'S), pattern of condom usage with CSW'S and factors influencing it were studied. We found that a significant number of drivers and helpers had sexual contact with CSW's and out of these, 30% of drivers and 50% of helpers reported not using condoms and instead resorting to methods like washing genitalia after sex with battery water/urine to avoid getting HIV. There was no significant relationship between pattern of condom usage and educational status, marital status and age. We also found that certain myths like sex with young CSW's was less likely to cause sexually transmitted diseases (STD's) and HIV were also widespread. Owing to continuing prevalence of such sexual myths, long distance truck drivers and helpers do not use condoms while having sex with CSW's as they feel that they can enjoy sex with CSW's and still stay protected against STD's/HIV. It is imperative that this battery water/urine antiseptic myth be specifically targeted for better HIV control in this high risk group. © The Author 2015. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Distance Teacher Education in Pakistan

    ERIC Educational Resources Information Center

    Jumani, Nabi Bux; Zai, Zafar Iqbal Yousuf

    2009-01-01

    Distance education means instruction in which the instructor and student are separated by distance and interact through the assistance of communication technology. Distance education changes the learning relationship from the common, centralized school model to a more decentralized, flexible model. It also reverses social dynamics by bringing…

  11. Connecting long distance: semantic distance in analogical reasoning modulates frontopolar cortex activity.

    PubMed

    Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N

    2010-01-01

    Solving problems often requires seeing new connections between concepts or events that seemed unrelated at first. Innovative solutions of this kind depend on analogical reasoning, a relational reasoning process that involves mapping similarities between concepts. Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key characteristic of the kind of analogical mapping that can support innovation (i.e., identifying similarities across greater semantic distance reveals connections that support more innovative solutions and models). However, the neural substrates of semantically distant analogical mapping are not well understood. Here, we used functional magnetic resonance imaging (fMRI) to measure brain activity during an analogical reasoning task, in which we parametrically varied the semantic distance between the items in the analogies. Semantic distance was derived quantitatively from latent semantic analysis. Across 23 participants, activity in an a priori region of interest (ROI) in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. This ROI was centered on a functional peak that we previously associated with analogical mapping. To our knowledge, these data represent a first empirical characterization of how the brain mediates semantically distant analogical mapping.

  12. Estimating Distances from Parallaxes. III. Distances of Two Million Stars in the Gaia DR1 Catalogue

    NASA Astrophysics Data System (ADS)

    Astraatmadja, Tri L.; Bailer-Jones, Coryn A. L.

    2016-12-01

    We infer distances and their asymmetric uncertainties for two million stars using the parallaxes published in the Gaia DR1 (GDR1) catalogue. We do this with two distance priors: A minimalist, isotropic prior assuming an exponentially decreasing space density with increasing distance, and an anisotropic prior derived from the observability of stars in a Milky Way model. We validate our results by comparing our distance estimates for 105 Cepheids which have more precise, independently estimated distances. For this sample we find that the Milky Way prior performs better (the rms of the scaled residuals is 0.40) than the exponentially decreasing space density prior (rms is 0.57), although for distances beyond 2 kpc the Milky Way prior performs worse, with a bias in the scaled residuals of -0.36 (versus -0.07 for the exponentially decreasing space density prior). We do not attempt to include the photometric data in GDR1 due to the lack of reliable color information. Our distance catalog is available at http://www.mpia.de/homes/calj/tgas_distances/main.html as well as at CDS. This should only be used to give individual distances. Combining data or testing models should be done with the original parallaxes, and attention paid to correlated and systematic uncertainties.

  13. Influence of distance between focusing lens and target surface on laser-induced Cu plasma temperature

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Chen, Anmin; Wang, Qiuyun; Sui, Laizhi; Ke, Da; Cao, Sheng; Li, Suyu; Jiang, Yuanfei; Jin, Mingxing

    2018-03-01

    In this study, the influence of distance between the focusing lens and target surface on the plasma temperature of copper induced by a Nd:YAG laser was investigated in the atmosphere. The plasma temperature was calculated by using the Cu (I) lines (510.55 nm, 515.32 nm, and 521.82 nm). The Cu (I) lines were recorded under different lens-to-sample distances and laser pulse energies (15.8 mJ, 27.0 mJ, 43.4 mJ, 59.2 mJ, and 76.8 mJ). The results indicated that the plasma temperature depended strongly on the distance between the focusing lens and target surface. With the increase in the distance, the plasma temperature firstly rose, and then dropped. This could be attributed to the interaction between the tailing of the nanosecond laser pulse and the front portion of the plasma plume, the plasma shielding effect, and the expanding of the plasma. In addition, there was an interesting phenomenon that the plasma temperature and the emission intensity were not completely consistent with the change of the lens-to-sample distance. It is hoped that our research will provide a deeper insight into the underlying physical processes.

  14. Development and Validation of a Path Length Calculation for Carotid-Femoral Pulse Wave Velocity Measurement: A TASCFORCE, SUMMIT, and Caerphilly Collaborative Venture.

    PubMed

    Weir-McCall, Jonathan R; Brown, Liam; Summersgill, Jennifer; Talarczyk, Piotr; Bonnici-Mallia, Michael; Chin, Sook C; Khan, Faisel; Struthers, Allan D; Sullivan, Frank; Colhoun, Helen M; Shore, Angela C; Aizawa, Kunihiko; Groop, Leif; Nilsson, Jan; Cockcroft, John R; McEniery, Carmel M; Wilkinson, Ian B; Ben-Shlomo, Yoav; Houston, J Graeme

    2018-05-01

    Current distance measurement techniques for pulse wave velocity (PWV) calculation are susceptible to intercenter variability. The aim of this study was to derive and validate a formula for this distance measurement. Based on carotid femoral distance in 1183 whole-body magnetic resonance angiograms, a formula was derived for calculating distance. This was compared with distance measurements in 128 whole-body magnetic resonance angiograms from a second study. The effects of recalculation of PWV using the new formula on association with risk factors, disease discrimination, and prediction of major adverse cardiovascular events were examined within 1242 participants from the multicenter SUMMIT study (Surrogate Markers of Micro- and Macrovascular Hard End-Points for Innovative Diabetes Tools) and 825 participants from the Caerphilly Prospective Study. The distance formula yielded a mean error of 7.8 mm (limits of agreement =-41.1 to 56.7 mm; P <0.001) compared with the second whole-body magnetic resonance angiogram group. Compared with an external distance measurement, the distance formula did not change associations between PWV and age, blood pressure, or creatinine ( P <0.01) but did remove significant associations between PWV and body mass index (BMI). After accounting for differences in age, sex, and mean arterial pressure, intercenter differences in PWV persisted using the external distance measurement ( F =4.6; P =0.004), whereas there was a loss of between center difference using the distance formula ( F =1.4; P =0.24). PWV odds ratios for cardiovascular mortality remained the same using both the external distance measurement (1.14; 95% confidence interval, 1.06-1.24; P =0.001) and the distance formula (1.17; 95% confidence interval, 1.08-1.28; P <0.001). A population-derived automatic distance calculation for PWV obtained from routinely collected clinical information is accurate and removes intercenter measurement variability without impacting the diagnostic

  15. Managing drugs safely.

    PubMed

    van den Anker, John N

    2005-02-01

    There is hard data to show that newborn infants are more likely than adults to experience adverse reactions to drugs. Paradoxically, drug-related legislation to ensure safe and effective drug use in humans neglected neonates until 2002, when the Best Pharmaceuticals Act for Children was signed into law in the USA. The situation for neonates should now catch up with that for adults and neonates will be prescribed more licensed drugs in the near future. If we are to be able to analyze the underlying system errors to improve the safe use of drugs in the studied patient population, reporting of adverse drug events and reactions needs to happen in a blame free environment. In addition, computerized physician order entry will certainly further improve the current situation by preventing errors in ordering, transcribing, verifying, and transmitting medication orders.

  16. Oscillation characteristics of neutrino in the model with three sterile neutrinos for analysis of the anomalies on small distances

    NASA Astrophysics Data System (ADS)

    Khruschov, V. V.; Fomichev, S. V.

    2017-11-01

    In the framework of the model with three sterile neutrinos, the transition probabilities for different flavours of neutrino are calculated and the graphical dependences are obtained, in particular, for the appearance probability of electron neutrino and antineutrino in the muon neutrino and antineutrino jets as a function of distance and other model parameters at their acceptable values and at the neutrino energy less than 50 MeV, as well as a function of a ratio of distance to the neutrino energy. The theoretical results obtained can be used for analysis of the neutrino data related to the anomalies on small distances.

  17. The Two Modes of Distance Education.

    ERIC Educational Resources Information Center

    Keegan, Desmond

    1998-01-01

    Discusses two models of distance-education, group-based versus individual-based. Highlights include group-based distance education for full-time and part-time students; individual-based distance education with pre-prepared materials and without pre-prepared materials; and distance education management and research. (LRW)

  18. Long-Distance Free Fall

    NASA Astrophysics Data System (ADS)

    Gallant, Joseph

    1999-04-01

    One of the goals of physics education is to instill a sense of wonder in our students. We hope our natural curiosity will rub off on them and that they will apply the critical thinking skills we teach them to other aspects of their lives outside the classroom. As an example of this, consider the situation described in Milton's epic poem ``Paradise Lost''. Milton wrote that when the devil was cast out of heaven, he fell for nine days before landing in hell. In Milton's universe, hell is a separate place from Earth, but many people place hell at the center of the Earth. Based on these ideas, we can apply Newton's laws of motion to calculate the distance from heaven to Earth. This exercise is an example of the kind of intellectual exercise a physicist (or a physics student) might carry out when confronted with such information. We apply the basic principles of physics to a situation described in work of literature while making no attempt to validate or refute any philosophy, theology or ideology.

  19. Cosmic distance duality and cosmic transparency

    NASA Astrophysics Data System (ADS)

    Nair, Remya; Jhingan, Sanjay; Jain, Deepak

    2012-12-01

    We compare distance measurements obtained from two distance indicators, Supernovae observations (standard candles) and Baryon acoustic oscillation data (standard rulers). The Union2 sample of supernovae with BAO data from SDSS, 6dFGS and the latest BOSS and WiggleZ surveys is used in search for deviations from the distance duality relation. We find that the supernovae are brighter than expected from BAO measurements. The luminosity distances tend to be smaller then expected from angular diameter distance estimates as also found in earlier works on distance duality, but the trend is not statistically significant. This further constrains the cosmic transparency.

  20. Perceptual distance and the moon illusion.

    PubMed

    Kaufman, Lloyd; Vassiliades, Vassias; Noble, Richard; Alexander, Robert; Kaufman, James; Edlund, Stefan

    2007-01-01

    The elevated moon usually appears smaller than the horizon moon of equal angular size. This is the moon illusion. Distance cues may enable the perceptual system to place the horizon moon at an effectively greater distance than the elevated moon, thus making it appear as larger. This explanation is related to the size-distance invariance hypothesis. However, the larger horizon moon is usually judged as closer than the smaller zenith moon. A bias to expect an apparently large object to be closer than a smaller object may account for this conflict. We designed experiments to determine if unbiased sensitivity to illusory differences in the size and distance of the moon (as measured by d') is consistent with SDIH. A moon above a 'terrain' was compared in both distance and size to an infinitely distant moon in empty space (the reduction moon). At a short distance the terrain moon was adjudged as both closer and smaller than the reduction moon. But these differences could not be detected at somewhat greater distances. At still greater distances the terrain moon was perceived as both more distant and larger than the reduction moon. The distances at which these transitions occurred were essentially the same for both distance and size discrimination tasks, thus supporting SDIH.

  1. Language distance and tree reconstruction

    NASA Astrophysics Data System (ADS)

    Petroni, Filippo; Serva, Maurizio

    2008-08-01

    Languages evolve over time according to a process in which reproduction, mutation and extinction are all possible. This is very similar to haploid evolution for asexual organisms and for the mitochondrial DNA of complex ones. Exploiting this similarity, it is possible, in principle, to verify hypotheses concerning the relationship among languages and to reconstruct their family tree. The key point is the definition of the distances among pairs of languages in analogy with the genetic distances among pairs of organisms. Distances can be evaluated by comparing grammar and/or vocabulary, but while it is difficult, if not impossible, to quantify grammar distance, it is possible to measure a distance from vocabulary differences. The method used by glottochronology computes distances from the percentage of shared 'cognates', which are words with a common historical origin. The weak point of this method is that subjective judgment plays a significant role. Here we define the distance of two languages by considering a renormalized edit distance among words with the same meaning and averaging over the two hundred words contained in a Swadesh list. In our approach the vocabulary of a language is the analogue of DNA for organisms. The advantage is that we avoid subjectivity and, furthermore, reproducibility of results is guaranteed. We apply our method to the Indo-European and the Austronesian groups, considering, in both cases, fifty different languages. The two trees obtained are, in many respects, similar to those found by glottochronologists, with some important differences as regards the positions of a few languages. In order to support these different results we separately analyze the structure of the distances of these languages with respect to all the others.

  2. Pathloss Calculation Using the Transmission Line Matrix and Finite Difference Time Domain Methods With Coarse Grids

    DOE PAGES

    Nutaro, James; Kuruganti, Teja

    2017-02-24

    Numerical simulations of the wave equation that are intended to provide accurate time domain solutions require a computational mesh with grid points separated by a distance less than the wavelength of the source term and initial data. However, calculations of radio signal pathloss generally do not require accurate time domain solutions. This paper describes an approach for calculating pathloss by using the finite difference time domain and transmission line matrix models of wave propagation on a grid with points separated by distances much greater than the signal wavelength. The calculated pathloss can be kept close to the true value formore » freespace propagation with an appropriate selection of initial conditions. This method can also simulate diffraction with an error governed by the ratio of the signal wavelength to the grid spacing.« less

  3. Application of the ultrametric distance to portfolio taxonomy. Critical approach and comparison with other methods

    NASA Astrophysics Data System (ADS)

    Skórnik-Pokarowska, Urszula; Orłowski, Arkadiusz

    2004-12-01

    We calculate the ultrametric distance between the pairs of stocks that belong to the same portfolio. The ultrametric distance allows us to distinguish groups of shares that are related. In this way, we can construct a portfolio taxonomy that can be used for constructing an efficient portfolio. We also construct a portfolio taxonomy based not only on stock prices but also on economic indices such as liquidity ratio, debt ratio and sales profitability ratio. We show that a good investment strategy can be obtained by applying to the portfolio chosen by the taxonomy method the so-called Constant Rebalanced Portfolio.

  4. Comparison of analytical methods for calculation of wind loads

    NASA Technical Reports Server (NTRS)

    Minderman, Donald J.; Schultz, Larry L.

    1989-01-01

    The following analysis is a comparison of analytical methods for calculation of wind load pressures. The analytical methods specified in ASCE Paper No. 3269, ANSI A58.1-1982, the Standard Building Code, and the Uniform Building Code were analyzed using various hurricane speeds to determine the differences in the calculated results. The winds used for the analysis ranged from 100 mph to 125 mph and applied inland from the shoreline of a large open body of water (i.e., an enormous lake or the ocean) a distance of 1500 feet or ten times the height of the building or structure considered. For a building or structure less than or equal to 250 feet in height acted upon by a wind greater than or equal to 115 mph, it was determined that the method specified in ANSI A58.1-1982 calculates a larger wind load pressure than the other methods. For a building or structure between 250 feet and 500 feet tall acted upon by a wind rangind from 100 mph to 110 mph, there is no clear choice of which method to use; for these cases, factors that must be considered are the steady-state or peak wind velocity, the geographic location, the distance from a large open body of water, and the expected design life and its risk factor.

  5. Stereoscopic distance perception

    NASA Technical Reports Server (NTRS)

    Foley, John M.

    1989-01-01

    Limited cue, open-loop tasks in which a human observer indicates distances or relations among distances are discussed. By open-loop tasks, it is meant tasks in which the observer gets no feedback as to the accuracy of the responses. What happens when cues are added and when the loop is closed are considered. The implications of this research for the effectiveness of visual displays is discussed. Errors in visual distance tasks do not necessarily mean that the percept is in error. The error could arise in transformations that intervene between the percept and the response. It is argued that the percept is in error. It is also argued that there exist post-perceptual transformations that may contribute to the error or be modified by feedback to correct for the error.

  6. An Automated Safe-to-Mate (ASTM) Tester

    NASA Technical Reports Server (NTRS)

    Nguyen, Phuc; Scott, Michelle; Leung, Alan; Lin, Michael; Johnson, Thomas

    2013-01-01

    Safe-to-mate testing is a common hardware safety practice where impedance measurements are made on unpowered hardware to verify isolation, continuity, or impedance between pins of an interface connector. A computer-based instrumentation solution has been developed to resolve issues. The ASTM is connected to the circuit under test, and can then quickly, safely, and reliably safe-to-mate the entire connector, or even multiple connectors, at the same time.

  7. 2007-08 Distance Education Report

    ERIC Educational Resources Information Center

    Nevada System of Higher Education, 2008

    2008-01-01

    This report focuses on distance education within the Nevada System of Higher Education (NSHE) for the 2007-08 academic year and provides documentation of the substantial growth of distance education within all colleges and universities. Distance education is a field of continuous improvement and change, and NSHE institutions are constantly…

  8. Interactive Distance Learning in Connecticut.

    ERIC Educational Resources Information Center

    Pietras, Jesse John; Murphy, Robert J.

    This paper provides an overview of distance learning activities in Connecticut and addresses the feasibility of such activities. Distance education programs have evolved from the one dimensional electronic mail systems to the use of sophisticated digital fiber networks. The Middlesex Distance Learning Consortium has developed a long-range plan to…

  9. The Semantic Distance Task: Quantifying Semantic Distance with Semantic Network Path Length

    ERIC Educational Resources Information Center

    Kenett, Yoed N.; Levi, Effi; Anaki, David; Faust, Miriam

    2017-01-01

    Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We…

  10. Deciphering the Distance between Distance Education and Working Professionals in Difficult Geographies

    ERIC Educational Resources Information Center

    Pandey, Jatin; Singh, Manjari

    2015-01-01

    This study investigates the factors that draw working professionals towards distance education programs, and the factors that sustain their distance education experience. The study is conducted in difficult terrains of Uttarakhand, a hilly state in India which helps us investigate the phenomenon in difficult geographies. Through interviews of ten…

  11. Ram Accelerator Performance Calculations Using a Modified Version of the NASA CET89 Equilibrium Chemistry Code

    DTIC Science & Technology

    1994-12-01

    Army Research Laboratory ATTN: AMSRL-WT-PA Aberdeen Proving Ground, MD 21005-5066 9 . SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING...8 1.5 DISTANCE vs. TIME CALCULATION ........................................... 9 2. D ISCU SSIO N...21 Figure 9 : Comparison of calculated thrust curves ..................................... 32 v

  12. Strategies for safe injections.

    PubMed Central

    Battersby, A.; Feilden, R.; Stoeckel, P.; Da Silva, A.; Nelson, C.; Bass, A.

    1999-01-01

    In 1998, faced with growing international concern, WHO set out an approach for achieving injection safety that encompassed all elements from patients' expectations and doctors' prescribing habits to waste disposal. This article follows that lead and describes the implications of the approach for two injection technologies: sterilizable and disposable. It argues that focusing on any single technology diverts attention from the more fundamental need for health services to develop their own comprehensive strategies for safe injections. National health authorities will only be able to ensure that injections are administered safely if they take an approach that encompasses the whole system, and choose injection technologies that fit their circumstances. PMID:10680247

  13. Computations of Wall Distances Based on Differential Equations

    NASA Technical Reports Server (NTRS)

    Tucker, Paul G.; Rumsey, Chris L.; Spalart, Philippe R.; Bartels, Robert E.; Biedron, Robert T.

    2004-01-01

    The use of differential equations such as Eikonal, Hamilton-Jacobi and Poisson for the economical calculation of the nearest wall distance d, which is needed by some turbulence models, is explored. Modifications that could palliate some turbulence-modeling anomalies are also discussed. Economy is of especial value for deforming/adaptive grid problems. For these, ideally, d is repeatedly computed. It is shown that the Eikonal and Hamilton-Jacobi equations can be easy to implement when written in implicit (or iterated) advection and advection-diffusion equation analogous forms, respectively. These, like the Poisson Laplacian term, are commonly occurring in CFD solvers, allowing the re-use of efficient algorithms and code components. The use of the NASA CFL3D CFD program to solve the implicit Eikonal and Hamilton-Jacobi equations is explored. The re-formulated d equations are easy to implement, and are found to have robust convergence. For accurate Eikonal solutions, upwind metric differences are required. The Poisson approach is also found effective, and easiest to implement. Modified distances are not found to affect global outputs such as lift and drag significantly, at least in common situations such as airfoil flows.

  14. Proximity alert! Distance related cuneus activation in military veterans with anger and aggression problems.

    PubMed

    Heesink, Lieke; Edward Gladwin, Thomas; Terburg, David; van Honk, Jack; Kleber, Rolf; Geuze, Elbert

    2017-08-30

    Problems involving anger and aggression are common after military deployment, and may involve abnormal responses to threat. This study therefore investigated effects on neural activation related to threat and escapability among veterans with deployment experience. Twenty-seven male veterans with anger and aggression problems (Anger group) and 30 Control veterans performed a virtual predator-task during fMRI measurement. In this task, threat and proximity were manipulated. The distance of cues determined their possibility for escape. Cues signaled impending attack by zooming in towards the participant. If Threat cues, but not Safe cues, reached the participants without being halted by a button press, an aversive noise (105dB scream) was presented. In both the Threat and the Safe condition, closer proximity of the virtual predator resulted in stronger activation in the cuneus in the Anger versus Control group. The results suggest that anger and aggression problems are related to a generalized sensitivity to proximity rather than preparatory processes related to task-contingent aversive stimuli. Anger and aggression problems in natural, dynamically changing environments may be related to an overall heightened vigilance, which is non-adaptively driven by proximity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  15. Feeling safe during an inpatient hospitalization: a concept analysis.

    PubMed

    Mollon, Deene

    2014-08-01

    This paper aims to explore the critical attributes of the concept feeling safe. The safe delivery of care is a high priority; however; it is not really known what it means to the patient to 'feel safe' during an inpatient hospitalization. This analysis explores the topic of safety from the patient's perspective. Concept analysis. The data bases of CINAHL, Medline, PsychInfo and Google Scholar for the years 1995-2012 were searched using the terms safe and feeling safe. The eight-step concept analysis method of Walker and Avant was used to analyse the concept of feeling safe. Uses and defining attributes, as well as identified antecedents, consequences and empirical referents, are presented. Case examples are provided to assist in the understanding of defining attributes. Feeling safe is defined as an emotional state where perceptions of care contribute to a sense of security and freedom from harm. Four attributes were identified: trust, cared for, presence and knowledge. Relationship, environment and suffering are the antecedents of feeling safe, while control, hope and relaxed or calm are the consequences. Empirical referents and early development of a theory of feeling safe are explored. This analysis begins the work of synthesizing qualitative research already completed around the concept of feeling safe by defining the key attributes of the concept. Support for the importance of developing patient-centred models of care and creating positive environments where patients receive high-quality care and feel safe is provided. © 2014 John Wiley & Sons Ltd.

  16. Tangential gunshot wound with MagSafe ammunition.

    PubMed

    Rapkiewicz, Amy V; Tamburri, Robert; Basoa, Mark E; Catanese, Charles A

    2005-09-01

    MagSafe ammunition is a type of unconventional prefragmented ammunition. A fatal tangential gunshot wound involving MagSafe ammunition is presented. The ammunition and wound characteristics are discussed.

  17. openPDS: protecting the privacy of metadata through SafeAnswers.

    PubMed

    de Montjoye, Yves-Alexandre; Shmueli, Erez; Wang, Samuel S; Pentland, Alex Sandy

    2014-01-01

    The rise of smartphones and web services made possible the large-scale collection of personal metadata. Information about individuals' location, phone call logs, or web-searches, is collected and used intensively by organizations and big data researchers. Metadata has however yet to realize its full potential. Privacy and legal concerns, as well as the lack of technical solutions for personal metadata management is preventing metadata from being shared and reconciled under the control of the individual. This lack of access and control is furthermore fueling growing concerns, as it prevents individuals from understanding and managing the risks associated with the collection and use of their data. Our contribution is two-fold: (1) we describe openPDS, a personal metadata management framework that allows individuals to collect, store, and give fine-grained access to their metadata to third parties. It has been implemented in two field studies; (2) we introduce and analyze SafeAnswers, a new and practical way of protecting the privacy of metadata at an individual level. SafeAnswers turns a hard anonymization problem into a more tractable security one. It allows services to ask questions whose answers are calculated against the metadata instead of trying to anonymize individuals' metadata. The dimensionality of the data shared with the services is reduced from high-dimensional metadata to low-dimensional answers that are less likely to be re-identifiable and to contain sensitive information. These answers can then be directly shared individually or in aggregate. openPDS and SafeAnswers provide a new way of dynamically protecting personal metadata, thereby supporting the creation of smart data-driven services and data science research.

  18. openPDS: Protecting the Privacy of Metadata through SafeAnswers

    PubMed Central

    de Montjoye, Yves-Alexandre; Shmueli, Erez; Wang, Samuel S.; Pentland, Alex Sandy

    2014-01-01

    The rise of smartphones and web services made possible the large-scale collection of personal metadata. Information about individuals' location, phone call logs, or web-searches, is collected and used intensively by organizations and big data researchers. Metadata has however yet to realize its full potential. Privacy and legal concerns, as well as the lack of technical solutions for personal metadata management is preventing metadata from being shared and reconciled under the control of the individual. This lack of access and control is furthermore fueling growing concerns, as it prevents individuals from understanding and managing the risks associated with the collection and use of their data. Our contribution is two-fold: (1) we describe openPDS, a personal metadata management framework that allows individuals to collect, store, and give fine-grained access to their metadata to third parties. It has been implemented in two field studies; (2) we introduce and analyze SafeAnswers, a new and practical way of protecting the privacy of metadata at an individual level. SafeAnswers turns a hard anonymization problem into a more tractable security one. It allows services to ask questions whose answers are calculated against the metadata instead of trying to anonymize individuals' metadata. The dimensionality of the data shared with the services is reduced from high-dimensional metadata to low-dimensional answers that are less likely to be re-identifiable and to contain sensitive information. These answers can then be directly shared individually or in aggregate. openPDS and SafeAnswers provide a new way of dynamically protecting personal metadata, thereby supporting the creation of smart data-driven services and data science research. PMID:25007320

  19. Creating Safe Spaces for Music Learning

    ERIC Educational Resources Information Center

    Hendricks, Karin S.; Smith, Tawnya D.; Stanuch, Jennifer

    2014-01-01

    This article offers a practical model for fostering emotionally safe learning environments that instill in music students a positive sense of self-belief, freedom, and purpose. The authors examine the implications for music educators of creating effective learning environments and present recommendations for creating a safe space for learning,…

  20. Asymptotically safe standard model extensions?

    NASA Astrophysics Data System (ADS)

    Pelaggi, Giulio Maria; Plascencia, Alexis D.; Salvio, Alberto; Sannino, Francesco; Smirnov, Juri; Strumia, Alessandro

    2018-05-01

    We consider theories with a large number NF of charged fermions and compute the renormalization group equations for the gauge, Yukawa and quartic couplings resummed at leading order in 1 /NF. We construct extensions of the standard model where SU(2) and/or SU(3) are asymptotically safe. When the same procedure is applied to the Abelian U(1) factor, we find that the Higgs quartic can not be made asymptotically safe and stay perturbative at the same time.

  1. Canal Transportation and Centering Ability of ProTaper and SafeSider in Preparation of Curved Root Canals: A CBCT Evaluation

    PubMed Central

    Delgoshayi, Negar; Abbasi, Mansoure; Bakhtiar, Hengameh; Sakhdari, Shirin; Ghannad, Setareh; Ellini, Mohammad Reza

    2018-01-01

    Introduction: Maintaining the original central canal path is an important parameter in efficient root canal preparation. Instruments causing minimal changes in original canal path are preferred for this purpose. This study sought to compare canal transportation and centering ability of ProTaper and SafeSider instruments in curved mesiobuccal root canals of mandibular first molars using cone beam computed tomography (CBCT). Methods and Materials : In this experimental study, 30 mesiobuccal root canals of extracted human mandibular first molars with 20° to 40° curvature were randomly divided into two groups (n=15). After mounting in putty, preoperative CBCT scans were obtained of teeth. Root canals in group A were shaped using S1, S2, F1 and F2 of ProTaper system. Root canals in group B were instrumented to size 25 using SafeSider system according to the manufacturers’ instructions. Postoperative CBCT scans were then obtained. The distance between the external root surface and internal canal wall was measured at the mesial and distal at 1, 3 and 7 mm from the apex. The values measured on primary and secondary CBCT scans were compared to assess possible changes in original central canal path and canal transportation. Data were compared using the t-test and repeated measure ANOVA. Results: ProTaper and SafeSider were significantly different in terms of canal transportation and centering ability, and ProTaper was significantly superior to SafeSider in this respect (P<0.001). Conclusion: ProTaper (in contrast to SafeSider) is well capable of maintaining the original central canal path with the least amount of transportation. PMID:29707022

  2. Imaging Flash Lidar for Autonomous Safe Landing and Spacecraft Proximity Operation

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin; Roback, Vincent E.; Brewster, Paul F.; Hines, Glenn D.; Bulyshev, Alexander E.

    2016-01-01

    3-D Imaging flash lidar is recognized as a primary candidate sensor for safe precision landing on solar system bodies (Moon, Mars, Jupiter and Saturn moons, etc.), and autonomous rendezvous proximity operations and docking/capture necessary for asteroid sample return and redirect missions, spacecraft docking, satellite servicing, and space debris removal. During the final stages of landing, from about 1 km to 500 m above the ground, the flash lidar can generate 3-Dimensional images of the terrain to identify hazardous features such as craters, rocks, and steep slopes. The onboard fli1ght computer can then use the 3-D map of terrain to guide the vehicle to a safe location. As an automated rendezvous and docking sensor, the flash lidar can provide relative range, velocity, and bearing from an approaching spacecraft to another spacecraft or a space station from several kilometers distance. NASA Langley Research Center has developed and demonstrated a flash lidar sensor system capable of generating 16k pixels range images with 7 cm precision, at a 20 Hz frame rate, from a maximum slant range of 1800 m from the target area. This paper describes the lidar instrument design and capabilities as demonstrated by the closed-loop flight tests onboard a rocket-propelled free-flyer vehicle (Morpheus). Then a plan for continued advancement of the flash lidar technology will be explained. This proposed plan is aimed at the development of a common sensor that with a modest design adjustment can meet the needs of both landing and proximity operation and docking applications.

  3. Aging Theories for Establishing Safe Life Spans of Airborne Critical Structural Components

    NASA Technical Reports Server (NTRS)

    Ko, William L.

    2003-01-01

    New aging theories have been developed to establish the safe life span of airborne critical structural components such as B-52B aircraft pylon hooks for carrying air-launch drop-test vehicles. The new aging theories use the equivalent-constant-amplitude loading spectrum to represent the actual random loading spectrum with the same damaging effect. The crack growth due to random loading cycling of the first flight is calculated using the half-cycle theory, and then extrapolated to all the crack growths of the subsequent flights. The predictions of the new aging theories (finite difference aging theory and closed-form aging theory) are compared with the classical flight-test life theory and the previously developed Ko first- and Ko second-order aging theories. The new aging theories predict the number of safe flights as considerably lower than that predicted by the classical aging theory, and slightly lower than those predicted by the Ko first- and Ko second-order aging theories due to the inclusion of all the higher order terms.

  4. Minimum distance classification in remote sensing

    NASA Technical Reports Server (NTRS)

    Wacker, A. G.; Landgrebe, D. A.

    1972-01-01

    The utilization of minimum distance classification methods in remote sensing problems, such as crop species identification, is considered. Literature concerning both minimum distance classification problems and distance measures is reviewed. Experimental results are presented for several examples. The objective of these examples is to: (a) compare the sample classification accuracy of a minimum distance classifier, with the vector classification accuracy of a maximum likelihood classifier, and (b) compare the accuracy of a parametric minimum distance classifier with that of a nonparametric one. Results show the minimum distance classifier performance is 5% to 10% better than that of the maximum likelihood classifier. The nonparametric classifier is only slightly better than the parametric version.

  5. Interplay between strong correlation and adsorption distances: Co on Cu(001)

    NASA Astrophysics Data System (ADS)

    Bahlke, Marc Philipp; Karolak, Michael; Herrmann, Carmen

    2018-01-01

    Adsorbed transition metal atoms can have partially filled d or f shells due to strong on-site Coulomb interaction. Capturing all effects originating from electron correlation in such strongly correlated systems is a challenge for electronic structure methods. It requires a sufficiently accurate description of the atomistic structure (in particular bond distances and angles), which is usually obtained from first-principles Kohn-Sham density functional theory (DFT), which due to the approximate nature of the exchange-correlation functional may provide an unreliable description of strongly correlated systems. To elucidate the consequences of this popular procedure, we apply a combination of DFT with the Anderson impurity model (AIM), as well as DFT + U for a calculation of the potential energy surface along the Co/Cu(001) adsorption coordinate, and compare the results with those obtained from DFT. The adsorption minimum is shifted towards larger distances by applying DFT+AIM, or the much cheaper DFT +U method, compared to the corresponding spin-polarized DFT results, by a magnitude comparable to variations between different approximate exchange-correlation functionals (0.08 to 0.12 Å). This shift originates from an increasing correlation energy at larger adsorption distances, which can be traced back to the Co 3 dx y and 3 dz2 orbitals being more correlated as the adsorption distance is increased. We can show that such considerations are important, as they may strongly affect electronic properties such as the Kondo temperature.

  6. Calibration of RAVE distances to a large sample of Hipparcos stars

    NASA Astrophysics Data System (ADS)

    Francis, Charles

    2013-12-01

    A magnitude-limited population of 18 808 Hipparcos stars is used to calibrate distances for 52 794 RAdial Velocity Experiment (RAVE) stars, including dwarfs, giants and pre-main-sequence stars. I give treatments for a number of types of bias affecting calculation, including bias from the non-linear relationship between the quantity of interest (e.g., distance or distance modulus) and the measured quantity (parallax or visual magnitude), the Lutz-Kelker bias and bias due to variation in density of the stellar population. The use of a magnitude bound minimizes the Malmquist and the Lutz-Kelker bias, and avoids measurement bias resulting from the greater accuracy of Hipparcos parallaxes for brighter stars. The calibration is applicable to stars in 2MASS when there is some way to determine stellar class with reasonable confidence. For RAVE this is possible for hot dwarfs and using log g. The accuracy of the calibration is tested against Hipparcos stars with better than 2 per cent parallax errors, and by comparison of the RAVE velocity distribution with that of Hipparcos, and is found to improve upon previous estimates of luminosity distance. An estimate of the local standard of rest from RAVE data, (U0, V0, W0) = (14.9 ± 1.7, 15.3 ± 0.4, 6.9 ± 0.1) km s-1, shows excellent agreement with the current best estimate from extended Hipparcos compilation. The RAVE velocity distribution confirms the alignment of stellar motions with spiral structure.

  7. 76 FR 30495 - National Safe Boating Week, 2011

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-25

    ... Safe Boating Week, 2011 By the President of the United States of America A Proclamation As Americans... to watergoers. National Safe Boating Week is an opportunity to highlight the importance of safety... can save lives. Each year for National Safe Boating Week, the United States Coast Guard partners with...

  8. Machine learning enhanced optical distance sensor

    NASA Astrophysics Data System (ADS)

    Amin, M. Junaid; Riza, N. A.

    2018-01-01

    Presented for the first time is a machine learning enhanced optical distance sensor. The distance sensor is based on our previously demonstrated distance measurement technique that uses an Electronically Controlled Variable Focus Lens (ECVFL) with a laser source to illuminate a target plane with a controlled optical beam spot. This spot with varying spot sizes is viewed by an off-axis camera and the spot size data is processed to compute the distance. In particular, proposed and demonstrated in this paper is the use of a regularized polynomial regression based supervised machine learning algorithm to enhance the accuracy of the operational sensor. The algorithm uses the acquired features and corresponding labels that are the actual target distance values to train a machine learning model. The optimized training model is trained over a 1000 mm (or 1 m) experimental target distance range. Using the machine learning algorithm produces a training set and testing set distance measurement errors of <0.8 mm and <2.2 mm, respectively. The test measurement error is at least a factor of 4 improvement over our prior sensor demonstration without the use of machine learning. Applications for the proposed sensor include industrial scenario distance sensing where target material specific training models can be generated to realize low <1% measurement error distance measurements.

  9. Distance and devices - potential barriers to use of wireless handheld devices.

    PubMed

    Martyn, Julie; Larkin, Kevin; Sander, Teresa; Yuginovich, Trudy; Jamieson-Proctor, Romina

    2014-03-01

    This paper reports the findings of a research project investigating the use of iPods by student nurses to enhance their interactions with content, instructors and peers while located at a distance from their university campus. Wireless handheld devices (WHD) are an important tool in nursing environments that are undergoing rapid technological change. Preferred treatments, drug dosages, postsurgical care, and preventive healthcare regimens continually change and such devices allow students to rapidly confirm information while in the clinical area, thus fostering active learning and safe practice. A case study approach was adopted with each participating student cohort comprising a case. Multiple data collection methods were used to enable rich descriptions of each case. This paper focusses on factors, relating to the use of iPods, which influenced student learning in distance courses at two regional Queensland universities. It furthermore highlights a range of creative interventions reported by students and educators in resolving issues with their devices. The study found that connectivity difficulties, technology literacy level, compatibility of study resources with the WHDs, and small screen size were all factors that impacted negatively on the use of iPods in distance courses. The paper describes the responses of students and educators to the use of iPods for learning. This study concluded that nursing students and nursing educators alike may experience problems when WHD's are introduced to courses as a platform for learning. However, both students and educators can be innovative and resourceful in managing these problems and, when access to course resources that were enabled for viewing on the WHDs were available, the learning experience of the students and the teaching experience for the educators were enhanced. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. The visual perception of distance ratios outdoors.

    PubMed

    Norman, J Farley; Adkins, Olivia C; Dowell, Catherine J; Shain, Lindsey M; Hoyng, Stevie C; Kinnard, Jonathan D

    2017-05-01

    We conducted an experiment to evaluate the ability of 32 younger and older adults to visually perceive distances in an outdoor setting. On any given trial, the observers viewed 2 environmental distances and were required to estimate the distance ratio-the length of the (usually) larger distance relative to that of the shorter. The stimulus distance ratios ranged from 1.0 (the stimulus distances were identical) to 8.0 (1 distance interval was 8.0 times longer than the other). The stimulus distances were presented within a 26 m × 60 m portion of a grassy field. The observers were able to reliably estimate the stimulus distance ratios: The overall Pearson r correlation coefficient relating the judged and actual distance ratios was 0.762. Fifty-eight percent of the variance in the observers' perceived distance ratios could thus be accounted for by variations in the actual stimulus ratios. About half of the observers significantly underestimated the distance ratios, while the judgments of the remainder were essentially accurate. Significant modulatory effects of sex and age occurred, such that the male observers' judgments were the most precise, while those of the older males were the most accurate.

  11. The Elimination of Transfer Distances Is an Important Part of Hospital Design.

    PubMed

    Karvonen, Sauli; Nordback, Isto; Elo, Jussi; Havulinna, Jouni; Laine, Heikki-Jussi

    2017-04-01

    The objective of the present study was to describe how a specific patient flow analysis with from-to charts can be used in hospital design and layout planning. As part of a large renewal project at a university hospital, a detailed patient flow analysis was applied to planning the musculoskeletal surgery unit (orthopedics and traumatology, hand surgery, and plastic surgery). First, the main activities of the unit were determined. Next, the routes of all patients treated over the course of 1 year were studied, and their physical movements in the current hospital were calculated. An ideal layout of the new hospital was then generated to minimize transfer distances by placing the main activities with close to each other, according to the patient flow analysis. The actual architectural design was based on the ideal layout plan. Finally, we compared the current transfer distances to the distances patients will move in the new hospital. The methods enabled us to estimate an approximate 50% reduction in transfer distances for inpatients (from 3,100 km/year to 1,600 km/year) and 30% reduction for outpatients (from 2,100 km/year to 1,400 km/year). Patient transfers are nonvalue-added activities. This study demonstrates that a detailed patient flow analysis with from-to charts can substantially shorten transfer distances, thereby minimizing extraneous patient and personnel movements. This reduction supports productivity improvement, cross-professional teamwork, and patient safety by placing all patient flow activities close to each other. Thus, this method is a valuable additional tool in hospital design.

  12. Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

    PubMed

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2011-12-01

    The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

  13. Calculation of Resistive Loads for Elastic Resistive Exercises.

    PubMed

    Picha, Kelsey; Uhl, Tim

    2018-03-14

    What is the correct resistive load to start resistive training with elastic resistance to gain strength? This question is typically answered by the clinician's best estimate and patient's level of discomfort without objective evidence. To determine the average level of resistance to initiate a strengthening routine with elastic resistance following isometric strength testing. Cohort. Clinical. 34 subjects (31 ± 13 y, 73 ± 17 kg, 170 ± 12 cm). The force produced was measured in Newtons (N) with an isometric dynamometer. The force distance was the distance from center of joint to location of force applied was measured in meters to calculate torque that was called "Test Torque" for the purposes of this report. This torque data was converted to "Exercise Load" in pounds based on the location where the resistance was applied, specifically the distance away from the center of rotation of the exercising limb. The average amount of exercise load as percentage of initial Test Torque for each individual for each exercise was recorded to determine what the average level of resistance that could be used for elastic resistance strengthening program. The percentage of initial test torque calculated for the exercise was recorded for each exercise and torque produced was normalized to body weight. The average percentage of maximal isometric force that was used to initiate exercises was 30 ± 7% of test torque. This provides clinicians with an objective target load to start elastic resistance training. Individual variations will occur but utilization of a load cell during elastic resistance provides objective documentation of exercise progression.

  14. Safe injection practice among health care workers, Gharbiya, Egypt.

    PubMed

    Ismail, Nanees A; Aboul Ftouh, Aisha M; El Shoubary, Waleed H

    2005-01-01

    A cross-sectional study was conducted in 25 health care facilities in Gharbiya governorate to assess safe injection practices among health care workers (HCWs). Two questionnaires, one to collect information about administrative issues related to safe injection and the other to collect data about giving injections, exposure to needle stick injuries, hepatitis B vaccination status and safe injection training. Practices of injections were observed using a standardized checklist. The study revealed that there was lack of both national and local infection control policies and lack of most of the supplies needed for safe injection practices. Many safe practices were infrequent as proper needle manipulation before disposal (41%), safe needle disposal (47.5%), reuse of used syringe & needle (13.2%) and safe syringe disposal (0%). Exposure to needle stick injuries were common among the interviewed HCWs (66.2%) and hand washing was the common post exposure prophylaxis measure (63.4%). Only 11.3% of HCWs had full course hepatitis B vaccination. Infection control -including safe injections- training programs should be afforded to all HCWs.

  15. Safe handling of antineoplastic drugs.

    PubMed

    Harrison, B R

    1994-07-01

    Managers should be aware of the hazardous properties of antineoplastic drugs and of the procedures and equipment commonly recommended to provide a safe working environment for employees, patients, and visitors. Compliance with the many published guidelines should help ensure passage of the inevitable Occupational Safety and Health Administration (OSHA) or Joint Commission inspection. Acute and chronic toxicities of the antineoplastic drugs, the potential for exposure in the workplace, and the basic guidelines for safe handling of these agents are reviewed.

  16. SafeNet: a methodology for integrating general-purpose unsafe devices in safe-robot rehabilitation systems.

    PubMed

    Vicentini, Federico; Pedrocchi, Nicola; Malosio, Matteo; Molinari Tosatti, Lorenzo

    2014-09-01

    Robot-assisted neurorehabilitation often involves networked systems of sensors ("sensory rooms") and powerful devices in physical interaction with weak users. Safety is unquestionably a primary concern. Some lightweight robot platforms and devices designed on purpose include safety properties using redundant sensors or intrinsic safety design (e.g. compliance and backdrivability, limited exchange of energy). Nonetheless, the entire "sensory room" shall be required to be fail-safe and safely monitored as a system at large. Yet, sensor capabilities and control algorithms used in functional therapies require, in general, frequent updates or re-configurations, making a safety-grade release of such devices hardly sustainable in cost-effectiveness and development time. As such, promising integrated platforms for human-in-the-loop therapies could not find clinical application and manufacturing support because of lacking in the maintenance of global fail-safe properties. Under the general context of cross-machinery safety standards, the paper presents a methodology called SafeNet for helping in extending the safety rate of Human Robot Interaction (HRI) systems using unsafe components, including sensors and controllers. SafeNet considers, in fact, the robotic system as a device at large and applies the principles of functional safety (as in ISO 13489-1) through a set of architectural procedures and implementation rules. The enabled capability of monitoring a network of unsafe devices through redundant computational nodes, allows the usage of any custom sensors and algorithms, usually planned and assembled at therapy planning-time rather than at platform design-time. A case study is presented with an actual implementation of the proposed methodology. A specific architectural solution is applied to an example of robot-assisted upper-limb rehabilitation with online motion tracking. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Going the Distance: A National Distance Learning Initiative.

    ERIC Educational Resources Information Center

    Dubois, Jaques R.

    1996-01-01

    Going the Distance is a Public Broadcasting Service project through which over 130 colleges and universities are offering telecourses for adults seeking associate degrees. It is the beginning of a global learning community. (SK)

  18. The trend of production rates with heliocentric distance for comet P/Halley

    NASA Technical Reports Server (NTRS)

    Fink, Uwe

    1994-01-01

    Comet P/Halley was observed spectroscopically in the wavelength range 5200-10,400 A during 10 observing runs, roughly a month apart from 1985 August 28 to 1986 June 6. The observations span a heliocentric distance from 0.73 to 2.52 AU. This data set is analyzed to determine the course of the production rate with heliocentric distance for C2, NH2, CN, and the continuum. The effect of changing the Haser scale lengths and their heliocentric distance dependence is examined. The production rate ratios to water change only in a minor way, but the absolute values of the production rates are more severely affected. Fluorescent efficiencies, or g-factors for the CN red system are calculated, and band intensity ratios for NH2 and CN are presented. Using presently available fluorescence efficiencies and Haser scale lengths, mixing ratios for the parents of C2, CN, and NH2 with respect to water are: 0.34 +/- 0.07%, 0.15 +/- 0.04%, and 0.13 +/- 0.05%. It is found that these mixing ratios are essentially constant over the heliocentric distance range of the observations, implying a rather uniform nucleus and uniform outgassing characteristics, although there are indications of smaller scale day-to-day variations. The results provide strong observational confirmation that water evaporation controls the activity of the comet over the distance range studied. Continuum values Af rho are determined, and their ratios to QH2O are found to have a clear dependence with heliocentric distance approximately r(exp -1.0) with a post-perihelion enhancement. No correlation of the production rate ratios with light curve of P/Halley were found, nor was there any correlation of the C2 or CN production with the dust.

  19. Tree-average distances on certain phylogenetic networks have their weights uniquely determined.

    PubMed

    Willson, Stephen J

    2012-01-01

    A phylogenetic network N has vertices corresponding to species and arcs corresponding to direct genetic inheritance from the species at the tail to the species at the head. Measurements of DNA are often made on species in the leaf set, and one seeks to infer properties of the network, possibly including the graph itself. In the case of phylogenetic trees, distances between extant species are frequently used to infer the phylogenetic trees by methods such as neighbor-joining. This paper proposes a tree-average distance for networks more general than trees. The notion requires a weight on each arc measuring the genetic change along the arc. For each displayed tree the distance between two leaves is the sum of the weights along the path joining them. At a hybrid vertex, each character is inherited from one of its parents. We will assume that for each hybrid there is a probability that the inheritance of a character is from a specified parent. Assume that the inheritance events at different hybrids are independent. Then for each displayed tree there will be a probability that the inheritance of a given character follows the tree; this probability may be interpreted as the probability of the tree. The tree-average distance between the leaves is defined to be the expected value of their distance in the displayed trees. For a class of rooted networks that includes rooted trees, it is shown that the weights and the probabilities at each hybrid vertex can be calculated given the network and the tree-average distances between the leaves. Hence these weights and probabilities are uniquely determined. The hypotheses on the networks include that hybrid vertices have indegree exactly 2 and that vertices that are not leaves have a tree-child.

  20. Fluctuations in Conjunction Miss Distance Projections as Time Approaches Time of Closest Approach

    NASA Technical Reports Server (NTRS)

    Christian, John A., III

    2005-01-01

    A responsibility of the Trajectory Operations Officer is to ensure that the International Space Station (ISS) avoids colliding with debris. United States Space Command (USSPACECOM) tracks and catalogs a portion of the debris in Earth orbit, but only objects with a perigee less than 600 km and a radar cross section (RCS) greater than 10 cm-objects that, in fact, represent only a small fraction of the objects in Earth orbit. To accommodate for this, the ISS uses shielding to protect against collisions with smaller objects. This study provides a better understanding of how quickly, and to what degree, USSPACECOM projections tend to converge to the final, true miss distance. The information included is formulated to better predict the behavior of miss distance data during real-time operations. It was determined that the driving components, in order of impact on miss distance fluctuations, are energy dissipation rate (EDR), RCS, and inclination. Data used in this analysis, calculations made, and conclusions drawn are stored in Microsoft Excel log sheets. A separate log sheet, created for each conjunction, contains information such as predicted miss distances, apogee and perigee of debris orbit, EDR, RCS, inclination, tracks and observations, statistical data, and other evaluation/orbital parameters.

  1. 77 FR 31147 - National Safe Boating Week, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Safe Boating Week, 2012 By the President of the United States of America A Proclamation For generations... friends and family a well- loved tradition. During National Safe Boating Week, we renew our commitment to... mark National Safe Boating Week, let us reflect on that important mission and resolve to do our part to...

  2. On the inversion-indel distance

    PubMed Central

    2013-01-01

    Background The inversion distance, that is the distance between two unichromosomal genomes with the same content allowing only inversions of DNA segments, can be computed thanks to a pioneering approach of Hannenhalli and Pevzner in 1995. In 2000, El-Mabrouk extended the inversion model to allow the comparison of unichromosomal genomes with unequal contents, thus insertions and deletions of DNA segments besides inversions. However, an exact algorithm was presented only for the case in which we have insertions alone and no deletion (or vice versa), while a heuristic was provided for the symmetric case, that allows both insertions and deletions and is called the inversion-indel distance. In 2005, Yancopoulos, Attie and Friedberg started a new branch of research by introducing the generic double cut and join (DCJ) operation, that can represent several genome rearrangements (including inversions). Among others, the DCJ model gave rise to two important results. First, it has been shown that the inversion distance can be computed in a simpler way with the help of the DCJ operation. Second, the DCJ operation originated the DCJ-indel distance, that allows the comparison of genomes with unequal contents, considering DCJ, insertions and deletions, and can be computed in linear time. Results In the present work we put these two results together to solve an open problem, showing that, when the graph that represents the relation between the two compared genomes has no bad components, the inversion-indel distance is equal to the DCJ-indel distance. We also give a lower and an upper bound for the inversion-indel distance in the presence of bad components. PMID:24564182

  3. Petroleum Jelly: Safe for a Dry Nose?

    MedlinePlus

    ... dryness. Is this safe? Answers from Lawrence E. Gibson, M.D. Petroleum jelly is generally safe to ... several hours of lying down. With Lawrence E. Gibson, M.D. Marchiori E, et al. Exogenous lipoid ...

  4. Taking Medicines Safely: At Your Doctor's Office

    MedlinePlus

    ... on. Feature: Taking Medicines Safely At Your Doctor's Office Past Issues / Summer 2013 Table of Contents Download ... Articles Medicines: Use Them Safely / At Your Doctor's Office / Ask Your Pharmacist / Now, It's Your Turn: How ...

  5. The Development and Calculation of an Energy-saving Plant for Obtaining Water from Atmospheric Air

    NASA Astrophysics Data System (ADS)

    Uglanov, D. A.; Zheleznyak, K. E.; Chertykovsev, P. A.

    2018-01-01

    The article shows the calculation of characteristics of energy-efficient water generator from atmospheric air. This installation or the atmospheric water generator is the unique mechanism which produces safe drinking water by extraction it from air. The existing atmospheric generators allow to receive safe drinking water by means of process of condensation at air humidity at least equal to 35% and are capable to give to 25 liters of water in per day, and work from electricity. Authors offer to use instead of the condenser in the scheme of installation for increase volume of produced water by generator in per day, the following refrigerating machines: the vapor compression refrigerating machines (VCRM), the thermoelectric refrigerating machines (TRM) and the Stirling-cycle refrigerating machines (SRM). The paper describes calculation methods for each of refrigerating systems. Calculation of technical-and-economic indexes for the atmospheric water generator was carried out and the optimum system with the maximum volume of received water in per day was picked up. The atmospheric water generator which is considered in article will work from autonomous solar power station.

  6. Closed-system drug-transfer devices plus safe handling of hazardous drugs versus safe handling alone for reducing exposure to infusional hazardous drugs in healthcare staff.

    PubMed

    Gurusamy, Kurinchi Selvan; Best, Lawrence Mj; Tanguay, Cynthia; Lennan, Elaine; Korva, Mika; Bussières, Jean-François

    2018-03-27

    Occupational exposure to hazardous drugs can decrease fertility and result in miscarriages, stillbirths, and cancers in healthcare staff. Several recommended practices aim to reduce this exposure, including protective clothing, gloves, and biological safety cabinets ('safe handling'). There is significant uncertainty as to whether using closed-system drug-transfer devices (CSTD) in addition to safe handling decreases the contamination and risk of staff exposure to infusional hazardous drugs compared to safe handling alone. To assess the effects of closed-system drug-transfer of infusional hazardous drugs plus safe handling versus safe handling alone for reducing staff exposure to infusional hazardous drugs and risk of staff contamination. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, OSH-UPDATE, CINAHL, Science Citation Index Expanded, economic evaluation databases, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov to October 2017. We included comparative studies of any study design (irrespective of language, blinding, or publication status) that compared CSTD plus safe handling versus safe handling alone for infusional hazardous drugs. Two review authors independently identified trials and extracted data. We calculated the risk ratio (RR) and mean difference (MD) with 95% confidence intervals (CI) using both fixed-effect and random-effects models. We assessed risk of bias according to the risk of bias in non-randomised studies of interventions (ROBINS-I) tool, used an intracluster correlation coefficient of 0.10, and we assessed the quality of the evidence using GRADE. We included 23 observational cluster studies (358 hospitals) in this review. We did not find any randomised controlled trials or formal economic evaluations. In 21 studies, the people who used the intervention (CSTD plus safe handling) and control (safe handling alone) were pharmacists or pharmacy

  7. KINEMATIC DISTANCES OF GALACTIC PLANETARY NEBULAE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, A. Y.; Tian, W. W.; Zhu, H.

    2016-03-15

    We construct H i absorption spectra for 18 planetary nebulae (PNs) and their background sources using data from the International Galactic Plane Survey. We estimate the kinematic distances of these PNs, among which 15 objects’ kinematic distances are obtained for the first time. The distance uncertainties of 13 PNs range from 10% to 50%, which is a significant improvement with uncertainties of a factor of two or three smaller than most previous distance measurements. We confirm that PN G030.2−00.1 is not a PN because of its large distance found here.

  8. The minimum distance approach to classification

    NASA Technical Reports Server (NTRS)

    Wacker, A. G.; Landgrebe, D. A.

    1971-01-01

    The work to advance the state-of-the-art of miminum distance classification is reportd. This is accomplished through a combination of theoretical and comprehensive experimental investigations based on multispectral scanner data. A survey of the literature for suitable distance measures was conducted and the results of this survey are presented. It is shown that minimum distance classification, using density estimators and Kullback-Leibler numbers as the distance measure, is equivalent to a form of maximum likelihood sample classification. It is also shown that for the parametric case, minimum distance classification is equivalent to nearest neighbor classification in the parameter space.

  9. From language identification to language distance

    NASA Astrophysics Data System (ADS)

    Gamallo, Pablo; Pichel, José Ramom; Alegria, Iñaki

    2017-10-01

    In this paper, we define two quantitative distances to measure how far apart two languages are. The distance measure that we have identified as more accurate is based on the perplexity of n-gram models extracted from text corpora. An experiment to compare forty-four European languages has been performed. For this purpose, we computed the distances for all the possible language pairs and built a network whose nodes are languages and edges are distances. The network we have built on the basis of linguistic distances represents the current map of similarities and divergences among the main languages of Europe.

  10. Model calculations of the interaction of two parallel antiaromatic 4n π-electron systems

    PubMed Central

    Böhm, Michael C.; Bickert, Peter; Hafner, Klaus; Boekelheide, V.

    1984-01-01

    The nature of the interaction between decks of a pentalene dimer and an s-indacene dimer has been studied by semi-empirical MNDO/1 and MINDO/3 calculations for distances between decks of from 5 Å to 2 Å. In contradiction to qualitative predictions from a frontier orbital analysis, it is found that the 4n-4n π-electron interaction between decks for such dimers is destabilizing for distances exceeding about 2.5 Å. PMID:16593458

  11. Distance and Cable Length Measurement System

    PubMed Central

    Hernández, Sergio Elias; Acosta, Leopoldo; Toledo, Jonay

    2009-01-01

    A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement. PMID:22303169

  12. VMD DisRg: New User-Friendly Implement for calculation distance and radius of gyration in VMD program

    PubMed Central

    Falsafi-Zadeh, Sajad; Karimi, Zahra; Galehdari, Hamid

    2012-01-01

    Molecular dynamic simulation is a practical and powerful technique for analysis of protein structure. Several programs have been developed to facilitate the mentioned investigation, under them the visual molecular dynamic or VMD is the most frequently used programs. One of the beneficial properties of the VMD is its ability to be extendable by designing new plug-in. We introduce here a new facility of the VMD for distance analysis and radius of gyration of biopolymers such as protein and DNA. Availability The database is available for free at http://trc.ajums.ac.ir/HomePage.aspx/?TabID/=12618/&Site/=trc.ajums.ac/&Lang/=fa-IR PMID:22553393

  13. Distance determination method of dust particles using Rosetta OSIRIS NAC and WAC data

    NASA Astrophysics Data System (ADS)

    Drolshagen, E.; Ott, T.; Koschny, D.; Güttler, C.; Tubiana, C.; Agarwal, J.; Sierks, H.; Barbieri, C.; Lamy, P. I.; Rodrigo, R.; Rickman, H.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J.-L.; Bertini, I.; Cremonese, G.; da Deppo, V.; Davidsson, B.; Debei, S.; de Cecco, M.; Deller, J.; Feller, C.; Fornasier, S.; Fulle, M.; Gicquel, A.; Groussin, O.; Gutiérrez, P. J.; Hofmann, M.; Hviid, S. F.; Ip, W.-H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Naletto, G.; Oklay, N.; Shi, X.; Thomas, N.; Poppe, B.

    2017-09-01

    The ESA Rosetta spacecraft has been tracking its target, the Jupiter-family comet 67P/Churyumov-Gerasimenko, in close vicinity for over two years. It hosts the OSIRIS instruments: the Optical, Spectroscopic, and Infrared Remote Imaging System composed of two cameras, see e.g. Keller et al. (2007). In some imaging sequences dedicated to observe dust particles in the comet's coma, the two cameras took images at the same time. The aim of this work is to use these simultaneous double camera observations to calculate the dust particles' distance to the spacecraft. As the two cameras are mounted on the spacecraft with an offset of 70 cm, the distance of particles observed by both cameras can be determined by a shift of the particles' apparent trails on the images. This paper presents first results of the ongoing work, introducing the distance determination method for the OSIRIS instrument and the analysis of an example particle. We note that this method works for particles in the range of about 500-6000 m from the spacecraft.

  14. Distance Education in Entwicklungslandern.

    ERIC Educational Resources Information Center

    German Foundation for International Development, Bonn (West Germany).

    Seminar and conference reports and working papers on distance education of adults, which reflect the experiences of many countries, are presented. Contents include the draft report of the 1979 International Seminar on Distance Education held in Addis Ababa, Ethiopia, which was jointly sponsored by the United Nations Economic Commission for Africa…

  15. Biomechanics of Distance Running.

    ERIC Educational Resources Information Center

    Cavanagh, Peter R., Ed.

    Contributions from researchers in the field of running mechanics are included in the 13 chapters of this book. The following topics are covered: (1) "The Mechanics of Distance Running: A Historical Perspective" (Peter Cavanagh); (2) "Stride Length in Distance Running: Velocity, Body Dimensions, and Added Mass Effects" (Peter Cavanagh, Rodger…

  16. The unassigned distance geometry problem

    DOE PAGES

    Duxbury, P. M.; Granlund, L.; Gujarathi, S. R.; ...

    2015-11-19

    Studies of distance geometry problems (DGP) have focused on cases where the vertices at the ends of all or most of the given distances are known or assigned, which we call assigned distance geometry problems (aDGPs). In this contribution we consider the unassigned distance geometry problem (uDGP) where the vertices associated with a given distance are unknown, so the graph structure has to be discovered. uDGPs arises when attempting to find the atomic structure of molecules and nanoparticles using X-ray or neutron diffraction data from non-crystalline materials. Rigidity theory provides a useful foundation for both aDGPs and uDGPs, though itmore » is restricted to generic realizations of graphs, and key results are summarized. Conditions for unique realization are discussed for aDGP and uDGP cases, build-up algorithms for both cases are described and experimental results for uDGP are presented.« less

  17. Strategies for Countering Terrorist Safe Havens

    DTIC Science & Technology

    2013-12-01

    tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case studies to examine these strategies...safe havens, tactical containment, pseudo operations, and surrogate security forces. The thesis draws from four historical case studies to examine...pseudo operations—provide viable potential options for USSOF to counter the complex problem of safe havens. Overall, the case studies will demonstrate

  18. QCD phenomenology of static sources and gluonic excitations at short distances

    NASA Astrophysics Data System (ADS)

    Bali, Gunnar S.; Pineda, Antonio

    2004-05-01

    New lattice data for the Πu and Σ-u potentials at short distances are presented. We compare perturbation theory to the lower static hybrid potentials and find good agreement at short distances, once the renormalon ambiguities are accounted for. We use the nonperturbatively determined continuum-limit static hybrid and ground state potentials at short distances to determine the gluelump energies. The result is consistent with an estimate obtained from the gluelump data at finite lattice spacings. For the lightest gluelump, we obtain ΛRSB(νf=2.5r-10)=[2.25±0.10(latt.)±0.21(th.)±0.08(ΛMS¯)]r-10 in the quenched approximation with r-10≈400 MeV. We show that, to quote sensible numbers for the absolute values of the gluelump energies, it is necessary to handle the singularities of the singlet and octet potentials in the Borel plane. We propose to subtract the renormalons of the short-distance matching coefficients, the potentials in this case. For the singlet potential the leading renormalon is already known and related to that of the pole mass; for the octet potential a new renormalon appears, which we approximately evaluate. We also apply our methods to heavy-light mesons in the static limit and from the lattice simulations available in the literature we obtain the quenched result Λ¯RS(νf=2.5r-10)=[1.17±0.08(latt.)±0.13(th.)±0.09(ΛMS¯)]r-10. We calculate mb,MS¯(mb,MS¯) and apply our methods to gluinonia whose dynamics are governed by the singlet potential between adjoint sources. We can exclude nonstandard linear short-distance contributions to the static potentials, with good accuracy.

  19. Implementation of Safe-by-Design for Nanomaterial Development and Safe Innovation: Why We Need a Comprehensive Approach

    PubMed Central

    Kraegeloh, Annette; Suarez-Merino, Blanca; Sluijters, Teun; Micheletti, Christian

    2018-01-01

    Manufactured nanomaterials (MNMs) are regarded as key components of innovations in various fields with high potential impact (e.g., energy generation and storage, electronics, photonics, diagnostics, theranostics, or drug delivery agents). Widespread use of MNMs raises concerns about their safety for humans and the environment, possibly limiting the impact of the nanotechnology-based innovation. The development of safe MNMs and nanoproducts has to result in a safe as well as functional material or product. Its safe use, and disposal at the end of its life cycle must be taken into account too. However, not all MNMs are similarly useful for all applications, some might bear a higher hazard potential than others, and use scenarios could lead to different exposure probabilities. To improve both safety and efficacy of nanotechnology, we think that a new proactive approach is necessary, based on pre-regulatory safety assessment and dialogue between stakeholders. On the basis of the work carried out in different European Union (EU) initiatives, developing and integrating MNMs Safe-by-Design and Trusted Environments (NANoREG, ProSafe, and NanoReg2), we present our point of view here. This concept, when fully developed, will allow for cost effective industrial innovation, and an exchange of key information between regulators and innovators. Regulators are thus informed about incoming innovations in good time, supporting a proactive regulatory action. The final goal is to contribute to the nanotechnology governance, having faster, cheaper, effective, and safer nano-products on the market. PMID:29661997

  20. Implementation of Safe-by-Design for Nanomaterial Development and Safe Innovation: Why We Need a Comprehensive Approach.

    PubMed

    Kraegeloh, Annette; Suarez-Merino, Blanca; Sluijters, Teun; Micheletti, Christian

    2018-04-14

    Manufactured nanomaterials (MNMs) are regarded as key components of innovations in various fields with high potential impact (e.g., energy generation and storage, electronics, photonics, diagnostics, theranostics, or drug delivery agents). Widespread use of MNMs raises concerns about their safety for humans and the environment, possibly limiting the impact of the nanotechnology-based innovation. The development of safe MNMs and nanoproducts has to result in a safe as well as functional material or product. Its safe use, and disposal at the end of its life cycle must be taken into account too. However, not all MNMs are similarly useful for all applications, some might bear a higher hazard potential than others, and use scenarios could lead to different exposure probabilities. To improve both safety and efficacy of nanotechnology, we think that a new proactive approach is necessary, based on pre-regulatory safety assessment and dialogue between stakeholders. On the basis of the work carried out in different European Union (EU) initiatives, developing and integrating MNMs Safe-by-Design and Trusted Environments (NANoREG, ProSafe, and NanoReg2), we present our point of view here. This concept, when fully developed, will allow for cost effective industrial innovation, and an exchange of key information between regulators and innovators. Regulators are thus informed about incoming innovations in good time, supporting a proactive regulatory action. The final goal is to contribute to the nanotechnology governance, having faster, cheaper, effective, and safer nano-products on the market.

  1. Environmentally safe fluid extractor

    DOEpatents

    Sungaila, Zenon F.

    1993-01-01

    An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

  2. Environmentally safe fluid extractor

    DOEpatents

    Sungaila, Zenon F.

    1993-07-06

    An environmentally safe fluid extraction device for use in mobile laboratory and industrial settings comprising a pump, compressor, valving system, waste recovery tank, fluid tank, and a exhaust filtering system.

  3. End-to-End Demonstrator of the Safe Affordable Fission Engine (SAFE) 30: Power Conversion and Ion Engine Operation

    NASA Technical Reports Server (NTRS)

    Hrbud, Ivana; VanDyke, Melissa; Houts, Mike; Goodfellow, Keith; Schafer, Charles (Technical Monitor)

    2001-01-01

    The Safe Affordable Fission Engine (SAFE) test series addresses Phase 1 Space Fission Systems issues in particular non-nuclear testing and system integration issues leading to the testing and non-nuclear demonstration of a 400-kW fully integrated flight unit. The first part of the SAFE 30 test series demonstrated operation of the simulated nuclear core and heat pipe system. Experimental data acquired in a number of different test scenarios will validate existing computational models, demonstrated system flexibility (fast start-ups, multiple start-ups/shut downs), simulate predictable failure modes and operating environments. The objective of the second part is to demonstrate an integrated propulsion system consisting of a core, conversion system and a thruster where the system converts thermal heat into jet power. This end-to-end system demonstration sets a precedent for ground testing of nuclear electric propulsion systems. The paper describes the SAFE 30 end-to-end system demonstration and its subsystems.

  4. Traversing State Boundaries with Distance Education: The Tri-State Agricultural Distance Delivery Alliance.

    ERIC Educational Resources Information Center

    Anderson, Erik T.; Makus, Larry; Fanno, Wayne; Swan, Mike

    The Tri-State Agricultural Distance Delivery Alliance (TADDA) is a new distance education consortium. The three land grant universities in the Pacific Northwest (the University of Idaho, Oregon State University, and Washington State University) developed TADDA in cooperation with Eastern Oregon University and four of the region's community…

  5. Results of 30 kWt Safe Affordable Fission Engine (SAFE-30) primary heat transport testing

    NASA Astrophysics Data System (ADS)

    Pedersen, Kevin; van Dyke, Melissa; Houts, Mike; Godfroy, Tom; Martin, James; Dickens, Ricky; Williams, Eric; Harper, Roger; Salvil, Pat; Reid, Bob

    2001-02-01

    The use of resistance heaters to simulate heat from fission allows extensive development of fission systems to be performed in non-nuclear test facilities, saving time and money. Resistance heated tests on the Safe Affordable Fission Engine-30 kilowatt (SAFE30) test article are being performed at the Marshall Space Flight Center. This paper discusses the results of these experiments to date, and describes the additional testing that will be performed. Recommendations related to the design of testable space fission power and propulsion systems are made. .

  6. Education at a Distance.

    ERIC Educational Resources Information Center

    Maffett, Sheryl Price

    2007-01-01

    Distance learning has been around since the old "course in a box" correspondence classes, but with the advent of sophisticated online course management systems, learning at a distance is contributing to a major paradigm shift in higher education. That shift includes applying corporate concepts to education--students, for example, are "consumers,"…

  7. Revised Distances to 21 Supernova Remnants

    NASA Astrophysics Data System (ADS)

    Ranasinghe, S.; Leahy, D. A.

    2018-05-01

    We carry out a comprehensive study of H I 21 cm line observations and 13CO line observations of 21 supernova remnants (SNRs). The aim of the study is to search for H I absorption features to obtain kinematic distances in a consistent manner. The 21 SNRs are in the region of sky covered by the Very Large Array Galactic Plane Survey (H I 21 cm observations) and Galactic Ring Survey (13CO line observations). We obtain revised distances for 10 SNRs based on new evidence in the H I and 13CO observations. We revise distances for the other 11 SNRs based on an updated rotation curve and new error analysis. The mean change in distance for the 21 SNRs is ≃25%, i.e., a change of 1.5 kpc compared to a mean distance for the sample of 6.4 kpc. This has a significant impact on interpretation of the physical state of these SNRs. For example, using a Sedov model, age and explosion energy scale as the square of distance, and inferred ISM density scales as distance.

  8. A method to calculate synthetic waveforms in stratified VTI media

    NASA Astrophysics Data System (ADS)

    Wang, W.; Wen, L.

    2012-12-01

    Transverse isotropy with a vertical axis of symmetry (VTI) may be an important material property in the Earth's interior. In this presentation, we develop a method to calculate synthetic seismograms for wave propagation in stratified VTI media. Our method is based on the generalized reflection and transmission method (GRTM) (Luco & Apsel 1983). We extend it to transversely isotropic VTI media. GRTM has the advantage of remaining stable in high frequency calculations compared to the Haskell Matrix method (Haskell 1964), which explicitly excludes the exponential growth terms in the propagation matrix and is limited to low frequency computation. In the implementation, we also improve GRTM in two aspects. 1) We apply the Shanks transformation (Bender & Orszag 1999) to improve the convergence rate of convergence. This improvement is especially important when the depths of source and receiver are close. 2) We adopt a self-adaptive Simpson integration method (Chen & Zhang 2001) in the discrete wavenumber integration so that the integration can still be efficiently carried out at large epicentral distances. Because the calculation is independent in each frequency, the program can also be effectively implemented in parallel computing. Our method provides a powerful tool to synthesize broadband seismograms of VIT media at a large epicenter distance range. We will present examples of using the method to study possible transverse isotropy in the upper mantle and the lowermost mantle.

  9. A Cognitively Grounded Measure of Pronunciation Distance

    PubMed Central

    Wieling, Martijn; Nerbonne, John; Bloem, Jelke; Gooskens, Charlotte; Heeringa, Wilbert; Baayen, R. Harald

    2014-01-01

    In this study we develop pronunciation distances based on naive discriminative learning (NDL). Measures of pronunciation distance are used in several subfields of linguistics, including psycholinguistics, dialectology and typology. In contrast to the commonly used Levenshtein algorithm, NDL is grounded in cognitive theory of competitive reinforcement learning and is able to generate asymmetrical pronunciation distances. In a first study, we validated the NDL-based pronunciation distances by comparing them to a large set of native-likeness ratings given by native American English speakers when presented with accented English speech. In a second study, the NDL-based pronunciation distances were validated on the basis of perceptual dialect distances of Norwegian speakers. Results indicated that the NDL-based pronunciation distances matched perceptual distances reasonably well with correlations ranging between 0.7 and 0.8. While the correlations were comparable to those obtained using the Levenshtein distance, the NDL-based approach is more flexible as it is also able to incorporate acoustic information other than sound segments. PMID:24416119

  10. Keeping Campuses Safe.

    ERIC Educational Resources Information Center

    Kennedy, Mike

    1999-01-01

    Describes how colleges and universities are using technology, as well as traditional methods, to keep campuses safe and reduce crime. Topics include using free pizza in a successful contest to teach students about campus safety, installing security cameras, using access-control cards, providing adequate lighting, and creating a bicycle patrol…

  11. Evaluation on Cost Overrun Risks of Long-distance Water Diversion Project Based on SPA-IAHP Method

    NASA Astrophysics Data System (ADS)

    Yuanyue, Yang; Huimin, Li

    2018-02-01

    Large investment, long route, many change orders and etc. are main causes for costs overrun of long-distance water diversion project. This paper, based on existing research, builds a full-process cost overrun risk evaluation index system for water diversion project, apply SPA-IAHP method to set up cost overrun risk evaluation mode, calculate and rank weight of every risk evaluation indexes. Finally, the cost overrun risks are comprehensively evaluated by calculating linkage measure, and comprehensive risk level is acquired. SPA-IAHP method can accurately evaluate risks, and the reliability is high. By case calculation and verification, it can provide valid cost overrun decision making information to construction companies.

  12. Safe Hazmat Storage Tips.

    ERIC Educational Resources Information Center

    Neville, Angela

    1996-01-01

    Provides a list of recommendations for safely managing hazardous waste containers. Encourages training of employees on the hazards of the wastes they handle and the correct procedures for managing containers. (DDR)

  13. What Safe Zone? The Vast Majority of Dislocated THAs Are Within the Lewinnek Safe Zone for Acetabular Component Position.

    PubMed

    Abdel, Matthew P; von Roth, Philipp; Jennings, Matthew T; Hanssen, Arlen D; Pagnano, Mark W

    2016-02-01

    Numerous factors influence total hip arthroplasty (THA) stability including surgical approach and soft tissue tension, patient compliance, and component position. One long-held tenet regarding component position is that cup inclination and anteversion of 40° ± 10° and 15° ± 10°, respectively, represent a "safe zone" as defined by Lewinnek that minimizes dislocation after primary THA; however, it is clear that components positioned in this zone can and do dislocate. We sought to determine if these classic radiographic targets for cup inclination and anteversion accurately predicted a safe zone limiting dislocation in a contemporary THA practice. From a cohort of 9784 primary THAs performed between 2003 and 2012 at one institution, we retrospectively identified 206 THAs (2%) that subsequently dislocated. Radiographic parameters including inclination, anteversion, center of rotation, and limb length discrepancy were analyzed. Mean followup was 27 months (range, 0-133 months). The majority (58% [120 of 206]) of dislocated THAs had a socket within the Lewinnek safe zone. Mean cup inclination was 44° ± 8° with 84% within the safe zone for inclination. Mean anteversion was 15° ± 9° with 69% within the safe zone for anteversion. Sixty-five percent of dislocated THAs that were performed through a posterior approach had an acetabular component within the combined acetabular safe zones, whereas this was true for only 33% performed through an anterolateral approach. An acetabular component performed through a posterior approach was three times as likely to be within the combined acetabular safe zones (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.1-1.6) than after an anterolateral approach (OR, 0.4; 95% CI, 0.2-0.7; p < 0.0001). In contrast, acetabular components performed through a posterior approach (OR, 1.6; 95% CI, 1.2-1.9) had an increased risk of dislocation compared with those performed through an anterolateral approach (OR, 0.8; 95% CI, 0.7-0.9; p

  14. Distance Education: An Overview.

    ERIC Educational Resources Information Center

    Batey, Anne; Cowell, Richard N.

    Distance education is a current "catch-all" phrase for any form of instruction in which the learner is linked to an educational institution and is formally enrolled, but instruction does not necessarily have to be delivered to or from an official school site. Distance education can provide equity and increase the quality of educational…

  15. Facilitating the safe use of insulin pens in hospitals through a mentored quality-improvement program.

    PubMed

    Lutz, Mark F; Haines, Stuart T; Lesch, Christine A; Szumita, Paul M

    2016-10-01

    Results of the MENTORED QUALITY IMPROVEMENT IMPACT PROGRAM℠ (MQIIP) on Ensuring Insulin Pen Safety in Hospitals, which was part of an ASHP educational initiative aimed at ensuring the safe use of insulin pens in hospitals, are described. During this ASHP initiative, which also included continuing-education activities and Web-based resources, distance mentoring by pharmacists with expertise in the safe use of insulin pens was provided to interprofessional teams at 14 hospitals between September 2014 and May 2015. The results of baseline assessments of nursing staff knowledge of insulin pen use, insulin pen storage and labeling audits, and insulin pen injection observations conducted in September and October 2014 were the basis for insulin pen quality-improvement plans. Postintervention data were collected in April and May 2015. Compared with the baseline period, significant improvements in nurses' knowledge of insulin pen use, insulin pen labeling and storage, and insulin pen administration were observed in the postintervention period despite the relatively short time frame for implementation of quality-improvement plans. Program participants are committed to sustaining and building on improvements achieved during the program. The outcome measures described in this report could be adapted by other health systems to identify opportunities to improve the safety of insulin pen use. Focused attention on insulin pen safety through an interprofessional team approach during the MQIIP enabled participating sites to detect potential safety issues based on collected data, develop targeted process changes, document improvements, and identify areas requiring further intervention. A sustained organizational commitment is required to ensure the safe use of insulin pen devices in hospitals. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  16. So What's an RTG and Are They Safe?

    NASA Technical Reports Server (NTRS)

    Barret, Chris; Hughes, R. W. (Technical Monitor)

    2001-01-01

    When one considers space missions to the outer edges of our solar system and far beyond, our sun cannot be relied on to produce the required spacecraft (s/c) power. Solar energy diminishes as the square of the distance from the Sun. At Mars it is only 43% of that at earth. At Jupiter, it falls off to only 3.6% of Earth's. By the time we get out to Pluto, solar energy is only .066% what it is on Earth. Beyond the orbit of Mars, it is not practical to depend on solar power for a s/c. However, the farther out we go the more power we need to heat the s/c and to transmit data back to Earth over the long distances. On Earth, knowledge is power. In the outer solar system, power is knowledge. Solar arrays only operate at 19% efficiency, are very vulnerable to damage from radiation and temperature extremes, and cannot be used for even nearby missions that operate in extended darkness, or under the surface of a planet or moon. Twenty-six U.S. space missions, from the Transit to Cassini, have used radioisotope power systems and heater units to take s/c to the far reaches of our solar system and have demonstrated an outstanding record of safety and reliability. Radioisotope thermoelectric generators (RTG's) have proven to be safe, reliable, maintenance-free, and capable of providing both thermal and electrical power for decades under the harsh environments of deep space. RTG's have no problem operating in the high radiation belts of space, the extreme temperatures, or the severe dust storms of Mars, and they have proven to be the most reliable power source ever flown on U.S. s/c. For example, the two Pioneer s/c operated for more than two decades and the Voyager s/c may last for 40 years. RTG's are not nuclear reactors, they serve only as power generators and are not involved in the propulsion of the s/c. They operate on the principle of thermoelectric generation that converts heat directly into electricity, they have no moving parts, are extremely reliable, and have met or

  17. Impact of distance to a urologist on early diagnosis of prostate cancer among black and white patients.

    PubMed

    Holmes, Jordan A; Carpenter, William R; Wu, Yang; Hendrix, Laura H; Peacock, Sharon; Massing, Mark; Schenck, Anna P; Meyer, Anne-Marie; Diao, Kevin; Wheeler, Stephanie B; Godley, Paul A; Stitzenberg, Karyn B; Chen, Ronald C

    2012-03-01

    We examined whether an increased distance to a urologist is associated with a delayed diagnosis of prostate cancer among black and white patients, as manifested by higher risk disease at diagnosis. North Carolina Central Cancer Registry data were linked to Medicare claims for patients with incident prostate cancer diagnosed in 2004 to 2005. Straight-line distances were calculated from the patient home to the nearest urologist. Race stratified multivariate ordinal logistic regression was used to examine the association between distance to a urologist and prostate cancer risk group (low, intermediate, high or very high/metastasis) at diagnosis for black and white patients while accounting for age, comorbidity, marital status and diagnosis year. An overall model was then used to examine the distance × race interaction effect. Included in analysis were 1,720 white and 531 black men. In the overall cohort the high risk cancer rate increased monotonically with distance to a urologist, including 40% for 0 to 10, 45% for 11 to 20 and 57% for greater than 20 miles. Correspondingly the low risk cancer rate decreased with longer distance. On race stratified multivariate analysis longer distance was associated with higher risk prostate cancer for white and black patients (p = 0.04 and <0.01, respectively) but the effect was larger in the latter group. The distance × race interaction term was significant in the overall model (p = 0.03). Longer distance to a urologist may disproportionally impact black patients. Decreasing modifiable barriers to health care access, such as distance to care, may decrease racial disparities in prostate cancer. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  18. Ab initio SCF calculations on the potential energy surface of potassium cyanide (KCN)

    NASA Astrophysics Data System (ADS)

    Wormer, Paul E. S.; Tennyson, Jonathan

    1981-08-01

    The potential energy surface of KCN has been generated by ab initio SCF calculations in the region of equilibrium bond distances. An analytic representation of the surface is presented. The calculations show that the bonding between K and CN is ionic, and that the structure of KCN is triangular, which confirms recent experimental findings. The computed geometry is &KCN = 62.4°, rCK = 5.492a0, and rCN = 2.186a0.

  19. Sleeping distance in wild wolf packs

    USGS Publications Warehouse

    Knick, S.T.; Mech, L.D.

    1980-01-01

    Sleeping distances were observed among members of 13 wild wolf (Canis lupus) packs and 11 pairs in northeastern Minnesota to determine if the distances correlated with pack size and composition. The study utilized aerial radio-tracking and observation during winter. Pack size and number of adults per pack were inversely related to pack average sleeping distance and variability. No correlation between sleeping distance and microclimate was observed. Possible relationships between social bonding and our results are discussed.

  20. Spectrum efficient distance-adaptive paths for fixed and fixed-alternate routing in elastic optical networks

    NASA Astrophysics Data System (ADS)

    Agrawal, Anuj; Bhatia, Vimal; Prakash, Shashi

    2018-01-01

    Efficient utilization of spectrum is a key concern in the soon to be deployed elastic optical networks (EONs). To perform routing in EONs, various fixed routing (FR), and fixed-alternate routing (FAR) schemes are ubiquitously used. FR, and FAR schemes calculate a fixed route, and a prioritized list of a number of alternate routes, respectively, between different pairs of origin o and target t nodes in the network. The route calculation performed using FR and FAR schemes is predominantly based on either the physical distance, known as k -shortest paths (KSP), or on the hop count (HC). For survivable optical networks, FAR usually calculates link-disjoint (LD) paths. These conventional routing schemes have been efficiently used for decades in communication networks. However, in this paper, it has been demonstrated that these commonly used routing schemes cannot utilize the network spectral resources optimally in the newly introduced EONs. Thus, we propose a new routing scheme for EON, namely, k -distance adaptive paths (KDAP) that efficiently utilizes the benefit of distance-adaptive modulation, and bit rate-adaptive superchannel capability inherited by EON to improve spectrum utilization. In the proposed KDAP, routes are found and prioritized on the basis of bit rate, distance, spectrum granularity, and the number of links used for a particular route. To evaluate the performance of KSP, HC, LD, and the proposed KDAP, simulations have been performed for three different sized networks, namely, 7-node test network (TEST7), NSFNET, and 24-node US backbone network (UBN24). We comprehensively assess the performance of various conventional, and the proposed routing schemes by solving both the RSA and the dual RSA problems under homogeneous and heterogeneous traffic requirements. Simulation results demonstrate that there is a variation amongst the performance of KSP, HC, and LD, depending on the o - t pair, and the network topology and its connectivity. However, the proposed

  1. Inertial sensing microelectromechanical (MEM) safe-arm device

    DOEpatents

    Roesler, Alexander W [Tijeras, NM; Wooden, Susan M [Sandia Park, NM

    2009-05-12

    Microelectromechanical (MEM) safe-arm devices comprise a substrate upon which a sense mass, that can contain an energetic material, is constrained to move along a pathway defined by a track disposed on the surface of the substrate. The pathway has a first end comprising a "safe" position and a second end comprising an "armed" position, whereat the second end the sense mass can be aligned proximal to energetic materials comprising the explosive train, within an explosive component. The sense mass can be confined in the safe position by a first latch, operable to release the sense mass by an acceleration acting in a direction substantially normal to the surface of the substrate. A second acceleration, acting in a direction substantially parallel to the surface of the substrate, can cause the sense mass to traverse the pathway from the safe position to the armed position.

  2. Graph distance for complex networks

    NASA Astrophysics Data System (ADS)

    Shimada, Yutaka; Hirata, Yoshito; Ikeguchi, Tohru; Aihara, Kazuyuki

    2016-10-01

    Networks are widely used as a tool for describing diverse real complex systems and have been successfully applied to many fields. The distance between networks is one of the most fundamental concepts for properly classifying real networks, detecting temporal changes in network structures, and effectively predicting their temporal evolution. However, this distance has rarely been discussed in the theory of complex networks. Here, we propose a graph distance between networks based on a Laplacian matrix that reflects the structural and dynamical properties of networked dynamical systems. Our results indicate that the Laplacian-based graph distance effectively quantifies the structural difference between complex networks. We further show that our approach successfully elucidates the temporal properties underlying temporal networks observed in the context of face-to-face human interactions.

  3. GIS modeling of seismic vulnerability of residential fabrics considering geotechnical, structural, social and physical distance indicators in Tehran using multi-criteria decision-making techniques

    NASA Astrophysics Data System (ADS)

    Rezaie, F.; Panahi, M.

    2015-03-01

    The main issue in determining seismic vulnerability is having a comprehensive view of all probable damages related to earthquake occurrence. Therefore, taking into account factors such as peak ground acceleration at the time of earthquake occurrence, the type of structures, population distribution among different age groups, level of education and the physical distance to hospitals (or medical care centers) and categorizing them into four indicators of geotechnical, structural, social and physical distance to needed facilities and from dangerous ones will provide us with a better and more exact outcome. To this end, this paper uses the analytic hierarchy process to study the importance of criteria or alternatives and uses the geographical information system to study the vulnerability of Tehran to an earthquake. This study focuses on the fact that Tehran is surrounded by three active and major faults: Mosha, North Tehran and Rey. In order to comprehensively determine the vulnerability, three scenarios are developed. In each scenario, seismic vulnerability of different areas in Tehran is analyzed and classified into four levels: high, medium, low and safe. The results show that, regarding seismic vulnerability, the faults of Mosha, North Tehran and Rey make, respectively, 6, 16 and 10% of Tehran highly vulnerable, while 34, 14 and 27% is safe.

  4. The distances of the Galactic Novae

    NASA Astrophysics Data System (ADS)

    Ozdonmez, Aykut; Guver, Tolga; Cabrera-Lavers, Antonio; Ak, Tansel

    2016-07-01

    Using location of the RC stars on the CMDs obtained from the UKIDSS, VISTA and 2MASS photometry, we have derived the reddening-distance relations towards each Galactic nova for which at least one independent reddening measurement exists. We were able to determine the distances of 72 Galactic novae and set lower limits on the distances of 45 systems. The reddening curves of the systems are presented. These curves can be also used to estimate reddening or the distance of any source, whose location is close to the position of the nova in our sample. The distance measurement method in our study can be easily applicable to any source, especially for ones that concentrated along the Galactic plane.

  5. Karate: Keep It Safe.

    ERIC Educational Resources Information Center

    Jordan, David

    1981-01-01

    Safety guidelines for each phase of a karate practice session are presented to provide an accident-free and safe environment for teaching karate in a physical education or traditional karate training program. (JMF)

  6. Prepare to protect: Operating and maintaining a tornado safe room.

    PubMed

    Herseth, Andrew; Goldsmith-Grinspoon, Jennifer; Scott, Pataya

    2017-06-01

    Operating and maintaining a tornado safe room can be critical to the effective continuity of business operations because a firm's most valuable asset is its people. This paper describes aspects of operations and maintenance (O&M) for existing tornado safe rooms as well as a few planning and design aspects that affect the ultimate operation of a safe room for situations where a safe room is planned, but not yet constructed. The information is based on several Federal Emergency Management Agency safe room publications that provide guidance on emergency management and operations, as well as the design and construction of tornado safe rooms.

  7. Optimal flight initiation distance.

    PubMed

    Cooper, William E; Frederick, William G

    2007-01-07

    Decisions regarding flight initiation distance have received scant theoretical attention. A graphical model by Ydenberg and Dill (1986. The economics of fleeing from predators. Adv. Stud. Behav. 16, 229-249) that has guided research for the past 20 years specifies when escape begins. In the model, a prey detects a predator, monitors its approach until costs of escape and of remaining are equal, and then flees. The distance between predator and prey when escape is initiated (approach distance = flight initiation distance) occurs where decreasing cost of remaining and increasing cost of fleeing intersect. We argue that prey fleeing as predicted cannot maximize fitness because the best prey can do is break even during an encounter. We develop two optimality models, one applying when all expected future contribution to fitness (residual reproductive value) is lost if the prey dies, the other when any fitness gained (increase in expected RRV) during the encounter is retained after death. Both models predict optimal flight initiation distance from initial expected fitness, benefits obtainable during encounters, costs of escaping, and probability of being killed. Predictions match extensively verified predictions of Ydenberg and Dill's (1986) model. Our main conclusion is that optimality models are preferable to break-even models because they permit fitness maximization, offer many new testable predictions, and allow assessment of prey decisions in many naturally occurring situations through modification of benefit, escape cost, and risk functions.

  8. Costo-iliac distance: a physical sign of understated importance.

    PubMed

    Barry, P J; O'Mahony, D

    2012-03-01

    Osteoporosis is a common condition, especially affecting the older female population. The ability to predict loss of lumbar height using simple anatomical measurements would be a useful tool. Forty subjects were recruited. Mean age was 72 years. Arm span (AS) and the costo-iliac distance (CID) were measured. The CID/AS ratio was calculated. The L(1)-L(4) vertebral height of each patient was obtained from dual-energy X-ray absorptiometry (DEXA). There was a statistically significant correlation between the lumbar height and CID/AS ratio (R (2) = 0.79, p < 0.001). The CID/AS ratio may be a useful bedside test in identifying loss of lumbar vertebral height.

  9. Review of "Successful, Safe, and Healthy Students"

    ERIC Educational Resources Information Center

    Glass, Gene V.; Barnett, Steven; Welner, Kevin G.

    2010-01-01

    The research summary "Successful, Safe, and Healthy Students" presents the research background for the Obama administration's proposals for comprehensive, community-wide services in high-poverty neighborhoods, extended learning time, family engagement and safe schools. While these policies have broad and common-sense appeal, the research…

  10. Energy system contributions in middle-distance running events.

    PubMed

    Hill, D W

    1999-06-01

    The aim of this study was to estimate the energy contributions in middle-distance running events for male and female university athletes. The oxygen uptake (VO2) response during high-speed running was measured directly during exhaustive treadmill tests. Muscle mass was estimated using anthropometry. Each athlete completed an average of three races over 400 m, 800 m or 1500 m. Five minutes after each race, they provided a blood sample for determination of blood lactate concentration. For each race, energy cost, which was expressed as oxygen equivalents, was calculated as the sum of the aerobic and anaerobic components. The aerobic contribution was calculated as the sum of oxygen stores (2.3 ml O2.kg body mass-1) and total VO2 (based on the VO2 response to treadmill running). The anaerobic contribution was calculated as the sum of the energy available from phosphocreatine stores (37 ml O2.kg muscle mass-1) and the energy from glycolysis (3.0 ml O2.kg body mass-1 per mmol.l-1 increase in blood lactate concentration). For the women, the anaerobic energy contributions for the 400 m, 800 m and 1500 m averaged 62%, 33% and 17%, respectively. For the men, the anaerobic contributions averaged 63%, 39% and 20%, respectively. This information will help coaches and sport scientists to design and implement individualized training programmes.

  11. Taking multiple medicines safely

    MedlinePlus

    ... medlineplus.gov/ency/patientinstructions/000883.htm Taking multiple medicines safely To use the sharing features on this ... directed. Why You May Need More Than One Medicine You may take more than one medicine to ...

  12. Monitoring Moving Queries inside a Safe Region

    PubMed Central

    Al-Khalidi, Haidar; Taniar, David; Alamri, Sultan

    2014-01-01

    With mobile moving range queries, there is a need to recalculate the relevant surrounding objects of interest whenever the query moves. Therefore, monitoring the moving query is very costly. The safe region is one method that has been proposed to minimise the communication and computation cost of continuously monitoring a moving range query. Inside the safe region the set of objects of interest to the query do not change; thus there is no need to update the query while it is inside its safe region. However, when the query leaves its safe region the mobile device has to reevaluate the query, necessitating communication with the server. Knowing when and where the mobile device will leave a safe region is widely known as a difficult problem. To solve this problem, we propose a novel method to monitor the position of the query over time using a linear function based on the direction of the query obtained by periodic monitoring of its position. Periodic monitoring ensures that the query is aware of its location all the time. This method reduces the costs associated with communications in client-server architecture. Computational results show that our method is successful in handling moving query patterns. PMID:24696652

  13. Distance Education in Papua New Guinea.

    ERIC Educational Resources Information Center

    Avalos, Beatrice, Ed.

    1991-01-01

    The theme of this special double serial issue is "Distance Education in Papua New Guinea." The following articles are featured: (1) "Distance Education in Papua New Guinea" (John Lynch); (2) "Distance Education in Papua New Guinea: Context, Issues and Prospects" (Michael Crossley and Richard Guy); (3) "Distance…

  14. An AERONET-Based Aerosol Classification Using the Mahalanobis Distance

    NASA Technical Reports Server (NTRS)

    Hamill, Patrick; Giordano, Marco; Ward, Carolyne; Giles, David; Holben, Brent

    2016-01-01

    We present an aerosol classification based on AERONET aerosol data from 1993 to 2012. We used the AERONET Level 2.0 almucantar aerosol retrieval products to define several reference aerosol clusters which are characteristic of the following general aerosol types: Urban-Industrial, Biomass Burning, Mixed Aerosol, Dust, and Maritime. The classification of a particular aerosol observation as one of these aerosol types is determined by its five-dimensional Mahalanobis distance to each reference cluster. We have calculated the fractional aerosol type distribution at 190 AERONET sites, as well as the monthly variation in aerosol type at those locations. The results are presented on a global map and individually in the supplementary material. Our aerosol typing is based on recognizing that different geographic regions exhibit characteristic aerosol types. To generate reference clusters we only keep data points that lie within a Mahalanobis distance of 2 from the centroid. Our aerosol characterization is based on the AERONET retrieved quantities, therefore it does not include low optical depth values. The analysis is based on point sources (the AERONET sites) rather than globally distributed values. The classifications obtained will be useful in interpreting aerosol retrievals from satellite borne instruments.

  15. Reference equations for the six-minute walk distance in the healthy Chinese population aged 18–59 years

    PubMed Central

    Zou, He; Zhu, Xiuruo; Zhang, Jia; Wang, Yi; Wu, Xiaozhen; Liu, Fang; Xie, Xiaofeng

    2017-01-01

    Background The six-minute walk test (6MWT) is a safe, simple, inexpensive tool for evaluating the functional exercise capacity of patients with chronic respiratory disease. However, there is a lack of standard reference equations for the six-minute walk distance (6MWD) in the healthy Chinese population aged 18–59 years. Aims The purposes of the present study were as follows: 1) to measure the anthropometric data and walking distance of a sample of healthy Chinese Han people aged 18–59 years; 2) to construct reference equations for the 6MWD; 3) to compare the measured 6MWD with previously published equations. Method The anthropometric data, demographic information, lung function, and walking distance of Chinese adults aged 18–59 years were prospectively measured using a standardized protocol. We obtained verbal consent from all the subjects before the test, and the study design was approved by the ethics committee of Wenzhou People's Hospital. The 6MWT was performed twice, and the longer distance was used for further analysis. Results A total of 643 subjects (319 females and 324 males) completed the 6MWT, and average walking distance was 601.6±55.51 m. The walking distance was compared between females and males (578±49.85 m vs. 623±52.53 m; p < 0.0001) and between physically active subjects and sedentary subjects (609.3±56.17 m vs. 592±53.23 m; p < 0.0001). Pearson’s correlation indicated that the 6MWD was significantly correlated with various demographic and the 6MWT variables, such as age, height, weight, body mass index (BMI), heart rate after the test and the difference in the heart rate before and after the test. Stepwise multiple regression analysis showed that age and height were independent predictors associated with the 6MWD. The reference equations from white, Canadian and Chilean populations tended to overestimate the walking distance in our subjects, while Brazilian and Arabian equations tended to underestimate the walking distance. There

  16. Equivalence Testing of Complex Particle Size Distribution Profiles Based on Earth Mover's Distance.

    PubMed

    Hu, Meng; Jiang, Xiaohui; Absar, Mohammad; Choi, Stephanie; Kozak, Darby; Shen, Meiyu; Weng, Yu-Ting; Zhao, Liang; Lionberger, Robert

    2018-04-12

    Particle size distribution (PSD) is an important property of particulates in drug products. In the evaluation of generic drug products formulated as suspensions, emulsions, and liposomes, the PSD comparisons between a test product and the branded product can provide useful information regarding in vitro and in vivo performance. Historically, the FDA has recommended the population bioequivalence (PBE) statistical approach to compare the PSD descriptors D50 and SPAN from test and reference products to support product equivalence. In this study, the earth mover's distance (EMD) is proposed as a new metric for comparing PSD particularly when the PSD profile exhibits complex distribution (e.g., multiple peaks) that is not accurately described by the D50 and SPAN descriptor. EMD is a statistical metric that measures the discrepancy (distance) between size distribution profiles without a prior assumption of the distribution. PBE is then adopted to perform statistical test to establish equivalence based on the calculated EMD distances. Simulations show that proposed EMD-based approach is effective in comparing test and reference profiles for equivalence testing and is superior compared to commonly used distance measures, e.g., Euclidean and Kolmogorov-Smirnov distances. The proposed approach was demonstrated by evaluating equivalence of cyclosporine ophthalmic emulsion PSDs that were manufactured under different conditions. Our results show that proposed approach can effectively pass an equivalent product (e.g., reference product against itself) and reject an inequivalent product (e.g., reference product against negative control), thus suggesting its usefulness in supporting bioequivalence determination of a test product to the reference product which both possess multimodal PSDs.

  17. Quantity Distance for the Kennedy Space Center Vehicle Assembly Building for Solid Propellant Fueled Launchers

    NASA Technical Reports Server (NTRS)

    Stover, Steven; Diebler, Corey; Frazier, Wayne

    2006-01-01

    The NASA KSC VAB was built to process Apollo launchers in the 1960's, and later adapted to process Space Shuttles. The VAB has served as a place to assemble solid rocket motors (5RM) and mate them to the vehicle's external fuel tank and Orbiter before rollout to the launch pad. As Space Shuttle is phased out, and new launchers are developed, the VAB may again be adapted to process these new launchers. Current launch vehicle designs call for continued and perhaps increased use of SRM segments; hence, the safe separation distances are in the process of being re-calculated. Cognizant NASA personnel and the solid rocket contractor have revisited the above VAB QD considerations and suggest that it may be revised to allow a greater number of motor segments within the VAB. This revision assumes that an inadvertent ignition of one SRM stack in its High Bay need not cause immediate and complete involvement of boosters that are part of a vehicle in adjacent High Bay. To support this assumption, NASA and contractor personnel proposed a strawman test approach for obtaining subscale data that may be used to develop phenomenological insight and to develop confidence in an analysis model for later use on full-scale situations. A team of subject matter experts in safety and siting of propellants and explosives were assembled to review the subscale test approach and provide options to NASA. Upon deliberations regarding the various options, the team arrived at some preliminary recommendations for NASA.

  18. Distance-limited perpendicular distance sampling for coarse woody debris: theory and field results

    Treesearch

    Mark J. Ducey; Micheal S. Williams; Jeffrey H. Gove; Steven Roberge; Robert S. Kenning

    2013-01-01

    Coarse woody debris (CWD) has been identified as an important component in many forest ecosystem processes. Perpendicular distance sampling (PDS) is one of the several efficient new methods that have been proposed for CWD inventory. One drawback of PDS is that the maximum search distance can be very large, especially if CWD diameters are large or the volume factor...

  19. Beth Reis and the Safe Schools Coalition

    ERIC Educational Resources Information Center

    Vaught, Sabina E.

    2007-01-01

    This article chronicles the formation and organization of the Safe Schools Coalition (SCC) through the experiences of Beth Reis, co-founder and co-Chair. The article suggests ways in which the SCC can serve as a model for both collective and individual work in promoting safe schools.

  20. The effect of emotional distance on psychophysiologic concordance and perceived empathy between patient and interviewer.

    PubMed

    Marci, Carl D; Orr, Scott P

    2006-06-01

    This preliminary study investigated the effect of emotional distance on psychophysiologic concordance and perceived empathy in a clinical population. Participants included 20 adult outpatients from a mental health clinic that underwent a brief semi-structured interview with a trained psychiatrist in either an emotionally neutral or an emotionally distant condition. Simultaneous skin conductance (SC) levels of the patient and interviewer were recorded and used to calculate a measure of psychophysiologic concordance. Interviewer gaze was rated by an independent observer and used as a proxy indicator of emotional distance. Observer ratings of interviewer gaze, SC concordance, and patient ratings of perceived interviewer empathy were significantly lower in the emotionally distant condition compared with the emotionally neutral condition (p < 0.05). Results suggest that increased emotional distance is associated with decreased psychophysiologic concordance and reduced subjective ratings of perceived empathy. The observed differences in psychophysiologic concordance support the use of this measure as a potential marker of empathy in a clinical population in an interview setting.

  1. Calibrating Reach Distance to Visual Targets

    ERIC Educational Resources Information Center

    Mon-Williams, Mark; Bingham, Geoffrey P.

    2007-01-01

    The authors investigated the calibration of reach distance by gradually distorting the haptic feedback obtained when participants grasped visible target objects. The authors found that the modified relationship between visually specified distance and reach distance could be captured by a straight-line mapping function. Thus, the relation could be…

  2. Phenological differences among selected residents and long-distance migrant bird species in central Europe

    NASA Astrophysics Data System (ADS)

    Bartošová, Lenka; Trnka, Miroslav; Bauer, Zdeněk; Možný, Martin; Štěpánek, Petr; Žalud, Zdeněk

    2014-07-01

    The phenological responses to climate of residents and migrants (short- and long-distance) differ. Although few previous studies have focussed on this topic, the agree that changes in phenology are more apparent for residents than for long-distance migrants. We analysed the breeding times of two selected residents ( Sitta europaea, Parus major) and one long-distance migrant ( Ficedula albicollis) from 1961 to 2007 in central Europe. The timing of the phenophases of all three bird species showed a significant advance to earlier times. Nevertheless, the most marked shift was observed for the long-distance migrant (1.9 days per decade on average in mean laying date with linearity at the 99.9 % confidence level). In contrast, the shifts shown by the residents were smaller (1.6 days for S. europaea and 1.5 days for P. major also on average in mean laying date for both, with linearity at the 95 % confidence level). Spearman rank correlation coefficients calculated for pairs of phenophases of given bird species in 20-year subsamples (e.g. 1961-1980, 1962-1981) showed higher phenological separation between the residents and the migrant. This separation is most apparent after the 1980s. Thus, our results indicate that the interconnections between the studied phenological stages of the three bird species are becoming weaker.

  3. Undergraduate paramedic students cannot do drug calculations

    PubMed Central

    Eastwood, Kathryn; Boyle, Malcolm J; Williams, Brett

    2012-01-01

    BACKGROUND: Previous investigation of drug calculation skills of qualified paramedics has highlighted poor mathematical ability with no published studies having been undertaken on undergraduate paramedics. There are three major error classifications. Conceptual errors involve an inability to formulate an equation from information given, arithmetical errors involve an inability to operate a given equation, and finally computation errors are simple errors of addition, subtraction, division and multiplication. The objective of this study was to determine if undergraduate paramedics at a large Australia university could accurately perform common drug calculations and basic mathematical equations normally required in the workplace. METHODS: A cross-sectional study methodology using a paper-based questionnaire was administered to undergraduate paramedic students to collect demographical data, student attitudes regarding their drug calculation performance, and answers to a series of basic mathematical and drug calculation questions. Ethics approval was granted. RESULTS: The mean score of correct answers was 39.5% with one student scoring 100%, 3.3% of students (n=3) scoring greater than 90%, and 63% (n=58) scoring 50% or less, despite 62% (n=57) of the students stating they ‘did not have any drug calculations issues’. On average those who completed a minimum of year 12 Specialist Maths achieved scores over 50%. Conceptual errors made up 48.5%, arithmetical 31.1% and computational 17.4%. CONCLUSIONS: This study suggests undergraduate paramedics have deficiencies in performing accurate calculations, with conceptual errors indicating a fundamental lack of mathematical understanding. The results suggest an unacceptable level of mathematical competence to practice safely in the unpredictable prehospital environment. PMID:25215067

  4. Undergraduate paramedic students cannot do drug calculations.

    PubMed

    Eastwood, Kathryn; Boyle, Malcolm J; Williams, Brett

    2012-01-01

    Previous investigation of drug calculation skills of qualified paramedics has highlighted poor mathematical ability with no published studies having been undertaken on undergraduate paramedics. There are three major error classifications. Conceptual errors involve an inability to formulate an equation from information given, arithmetical errors involve an inability to operate a given equation, and finally computation errors are simple errors of addition, subtraction, division and multiplication. The objective of this study was to determine if undergraduate paramedics at a large Australia university could accurately perform common drug calculations and basic mathematical equations normally required in the workplace. A cross-sectional study methodology using a paper-based questionnaire was administered to undergraduate paramedic students to collect demographical data, student attitudes regarding their drug calculation performance, and answers to a series of basic mathematical and drug calculation questions. Ethics approval was granted. The mean score of correct answers was 39.5% with one student scoring 100%, 3.3% of students (n=3) scoring greater than 90%, and 63% (n=58) scoring 50% or less, despite 62% (n=57) of the students stating they 'did not have any drug calculations issues'. On average those who completed a minimum of year 12 Specialist Maths achieved scores over 50%. Conceptual errors made up 48.5%, arithmetical 31.1% and computational 17.4%. This study suggests undergraduate paramedics have deficiencies in performing accurate calculations, with conceptual errors indicating a fundamental lack of mathematical understanding. The results suggest an unacceptable level of mathematical competence to practice safely in the unpredictable prehospital environment.

  5. Rough Way for Academics: Distance Education

    ERIC Educational Resources Information Center

    Gursul, Fatih

    2010-01-01

    This study aims to compare the academics' perceptions about face to face and distance education, beside finding out the contributions of distance education to them, difficulties they experience in synchronous and asynchronous distance education environments and suggestions for possible solutions of the existing problems. The sample consists of 52…

  6. Tidewater Community College Distance Learning Report.

    ERIC Educational Resources Information Center

    Tidewater Community Coll., Norfolk, VA.

    This study of distance learning at Tidewater Community College (TCC) was conducted to determine enrollment patterns, retention, and success in distance learning courses and student perceptions. Distance learning was defined as students enrolled in one of three modes of course delivery: telecourse, online, and compressed video. The time frame for…

  7. The Distancing Question in Online Education

    ERIC Educational Resources Information Center

    Russell, Glenn

    2005-01-01

    Intellectuals in many fields have long argued that, as the distance between people increases, the possibility for genuine empathy between them decreases. In this article, the author argues that distancing has as-yet unexplored pragmatic consequences in online education. As he has argued elsewhere (Russell 2004), distancing can be understood as…

  8. Staying away from the optic nerve: a formula for modifying glaucoma drainage device surgery in pediatric and other small eyes.

    PubMed

    Margeta, Milica A; Kuo, Anthony N; Proia, Alan D; Freedman, Sharon F

    2017-02-01

    To provide guidelines for safe implantation of glaucoma drainage devices (GDDs) in small and pediatric eyes to avoid contact between the optic nerve (ON) and the posterior edge of the GDD plate. We developed a formula for calculating limbus-to-ON distance to estimate the available "real estate" for GDD placement in small eyes. The formula was validated using eyes of pediatric decedents undergoing clinical autopsy, with axial lengths (AL) of 15-24 mm. For each autopsy eye, we measured AL, anterior chamber depth, corneal diameter, and limbus-to-ON distances for the four eye quadrants. The main outcome measure was the degree of agreement between measured and calculated limbus-to-ON distances. A total of 15 autopsy eyes were divided into derivation (n = 10) and validation (n = 5) groups. A formula was derived to estimate superotemporal limbus-to-ON distance (D ST ) using AL and corneal diameter data. Linear regression showed excellent correlation between the measured D ST and AL (R 2  = 0.98). There was excellent agreement between measured and calculated limbus-to-ON values for all four eye quadrants (R 2 range, 0.92-0.98). Our formula accurately predicts limbus-to-ON distances across a wide range of clinically relevant ALs. Based on this information, GDD surgery in small eyes can be adjusted by positioning the GDD closer to the limbus or by trimming the posterior edge of the GDD plate. To our knowledge, this is the first set of guidelines developed to promote safe implantation of GDDs in small eyes. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

  9. Virus Alert: Ten Steps to Safe Computing.

    ERIC Educational Resources Information Center

    Gunter, Glenda A.

    1997-01-01

    Discusses computer viruses and explains how to detect them; discusses virus protection and the need to update antivirus software; and offers 10 safe computing tips, including scanning floppy disks and commercial software, how to safely download files from the Internet, avoiding pirated software copies, and backing up files. (LRW)

  10. 16 CFR 312.11 - Safe harbor programs.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Safe harbor programs. 312.11 Section 312.11 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS CHILDREN'S ONLINE PRIVACY PROTECTION RULE § 312.11 Safe harbor programs. (a) In general. Industry groups or other persons...

  11. Web page sorting algorithm based on query keyword distance relation

    NASA Astrophysics Data System (ADS)

    Yang, Han; Cui, Hong Gang; Tang, Hao

    2017-08-01

    In order to optimize the problem of page sorting, according to the search keywords in the web page in the relationship between the characteristics of the proposed query keywords clustering ideas. And it is converted into the degree of aggregation of the search keywords in the web page. Based on the PageRank algorithm, the clustering degree factor of the query keyword is added to make it possible to participate in the quantitative calculation. This paper proposes an improved algorithm for PageRank based on the distance relation between search keywords. The experimental results show the feasibility and effectiveness of the method.

  12. Estimating Distances from Parallaxes. II. Performance of Bayesian Distance Estimators on a Gaia-like Catalogue

    NASA Astrophysics Data System (ADS)

    Astraatmadja, Tri L.; Bailer-Jones, Coryn A. L.

    2016-12-01

    Estimating a distance by inverting a parallax is only valid in the absence of noise. As most stars in the Gaia catalog will have non-negligible fractional parallax errors, we must treat distance estimation as a constrained inference problem. Here we investigate the performance of various priors for estimating distances, using a simulated Gaia catalog of one billion stars. We use three minimalist, isotropic priors, as well an anisotropic prior derived from the observability of stars in a Milky Way model. The two priors that assume a uniform distribution of stars—either in distance or in space density—give poor results: The root mean square fractional distance error, {f}{rms}, grows far in excess of 100% once the fractional parallax error, {f}{true}, is larger than 0.1. A prior assuming an exponentially decreasing space density with increasing distance performs well once its single parameter—the scale length— has been set to an appropriate value: {f}{rms} is roughly equal to {f}{true} for {f}{true}\\lt 0.4, yet does not increase further as {f}{true} increases up to to 1.0. The Milky Way prior performs well except toward the Galactic center, due to a mismatch with the (simulated) data. Such mismatches will be inevitable (and remain unknown) in real applications, and can produce large errors. We therefore suggest adopting the simpler exponentially decreasing space density prior, which is also less time-consuming to compute. Including Gaia photometry improves the distance estimation significantly for both the Milky Way and exponentially decreasing space density prior, yet doing so requires additional assumptions about the physical nature of stars.

  13. Towards eye-safe standoff Raman imaging systems

    NASA Astrophysics Data System (ADS)

    Glimtoft, Martin; Bââth, Petra; Saari, Heikki; Mäkynen, Jussi; Näsilä, Antti; Östmark, Henric

    2014-05-01

    Standoff Raman imaging systems have shown the ability to detect single explosives particles. However, in many cases, the laser intensities needed restrict the applications where they can be safely used. A new generation imaging Raman system has been developed based on a 355 nm UV laser that, in addition to eye safety, allows discrete and invisible measurements. Non-dangerous exposure levels for the eye are several orders of magnitude higher in UVA than in the visible range that previously has been used. The UV Raman system has been built based on an UV Fabry-Perot Interferometer (UV-FPI) developed by VTT. The design allows for precise selection of Raman shifts in combination with high out-of-band blocking. The stable operation of the UV-FPI module under varying environmental conditions is arranged by controlling the temperature of the module and using a closed loop control of the FPI air gap based on capacitive measurement. The system presented consists of a 3rd harmonics Nd:YAG laser with 1.5 W average output at 1000 Hz, a 200 mm Schmidt-Cassegrain telescope, UV-FPI filter and an ICCD camera for signal gating and detection. The design principal leads to a Raman spectrum in each image pixel. The system is designed for field use and easy manoeuvring. Preliminary results show that in measurements of <60 s on 10 m distance, single AN particles of <300 μm diameter can be identified.

  14. A distance education in undergraduate dietetic education.

    PubMed

    Benton-King, Carrie; Webb, Derek F; Holmes, ZoeAnn

    2005-01-01

    Distance education is an exploding phenomenon that allows people to pursue higher education on their own time, at a pace that meets their needs, in locations where there are no colleges and universities, or where there is not a desired program of study. This study examined the use of distance education in undergraduate dietetic education programs and the opportunities for obtaining an undergraduate degree in dietetics solely via distance education. A survey was sent to all directors (n = 279) of undergraduate programs accredited/approved by the Commission on Accreditation for Dietetics Education to determine the current status and projected future use of distance education in their institutions' on-campus programs. The survey had a 54% response rate. Approximately 32% (n = 150) of undergraduate dietetics programs offer distance education courses in some format. Institutions that offer nondietetics distance education courses were more likely to offer dietetics distance education courses. The most common distance education format utilized in dietetics was 100% Internet courses (48%). The most common distance education dietetics course offered was a basic or introductory nutrition course (31%). From the data of courses offered, or permitted to be transferred, it would not be possible for a student to complete an undergraduate degree in dietetics solely via distance education methodologies at the time this study was conducted.

  15. How Haptic Size Sensations Improve Distance Perception

    PubMed Central

    Battaglia, Peter W.; Kersten, Daniel; Schrater, Paul R.

    2011-01-01

    Determining distances to objects is one of the most ubiquitous perceptual tasks in everyday life. Nevertheless, it is challenging because the information from a single image confounds object size and distance. Though our brains frequently judge distances accurately, the underlying computations employed by the brain are not well understood. Our work illuminates these computions by formulating a family of probabilistic models that encompass a variety of distinct hypotheses about distance and size perception. We compare these models' predictions to a set of human distance judgments in an interception experiment and use Bayesian analysis tools to quantitatively select the best hypothesis on the basis of its explanatory power and robustness over experimental data. The central question is: whether, and how, human distance perception incorporates size cues to improve accuracy. Our conclusions are: 1) humans incorporate haptic object size sensations for distance perception, 2) the incorporation of haptic sensations is suboptimal given their reliability, 3) humans use environmentally accurate size and distance priors, 4) distance judgments are produced by perceptual “posterior sampling”. In addition, we compared our model's estimated sensory and motor noise parameters with previously reported measurements in the perceptual literature and found good correspondence between them. Taken together, these results represent a major step forward in establishing the computational underpinnings of human distance perception and the role of size information. PMID:21738457

  16. Safe Sleep for Babies

    MedlinePlus

    ... Every year, there are thousands of sleep-related deaths among babies. View large image and text description ... 2AZh9Bn Supporting research to better understand sleep-related deaths and strategies to improve safe sleep practices. Healthcare ...

  17. Geological conditions of safe long-term storage and disposal of depleted uranium hexafluoride

    NASA Astrophysics Data System (ADS)

    Laverov, N. P.; Velichkin, V. I.; Omel'Yanenko, B. I.; Yudintsev, S. V.; Tagirov, B. R.

    2010-08-01

    The production of enriched uranium used in nuclear weapons and fuel for atomic power plants is accompanied by the formation of depleted uranium (DU), the amount of which annually increases by 35-40 kt. To date, more than 1.6 Mt DU has accumulated in the world. The main DU mass is stored as environ-mentally hazardous uranium hexafluoride (UF6), which is highly volatile and soluble in water with the formation of hydrofluoric acid. To ensure safe UF6 storage, it is necessary to convert this compound in chemically stable phases. The industrial reprocessing of UF6 into U3O8 and HF implemented in France is highly expensive. We substantiate the expediency of long-term storage of depleted uranium hexafluoride in underground repositories localized in limestone. On the basis of geochemical data and thermodynamic calculations, we show that interaction in the steel container-UF6-limestone-groundwater system gives rise to the development of a slightly alkaline reductive medium favorable for chemical reaction with formation of uraninite (UO2) and fluorite (CaF2). The proposed engineering solution not only ensures safe DU storage but also makes it possible to produce uraninite, which can be utilized, if necessary, in fast-neutron reactors. In the course of further investigations aimed at safe maintenance of DU, it is necessary to study the kinetics of conversion of UF6 into stable phases, involving laboratory and field experiments.

  18. Cepheids Geometrical Distances Using Space Interferometry

    NASA Astrophysics Data System (ADS)

    Marengo, M.; Karovska, M.; Sasselov, D. D.; Sanchez, M.

    2004-05-01

    A space based interferometer with a sub-milliarcsecond resolution in the UV-optical will provide a new avenue for the calibration of primary distance indicators with unprecedented accuracy, by allowing very accurate and stable measurements of Cepheids pulsation amplitudes at wavelengths not accessible from the ground. Sasselov & Karovska (1994) have shown that interferometers allow very accurate measurements of Cepheids distances by using a ``geometric'' variant of the Baade-Wesselink method. This method has been succesfully applied to derive distances and radii of nearby Cepheids using ground-based near-IR and optical interferometers, within a 15% accuracy level. Our study shows that the main source of error in these measurements is due to the perturbing effects of the Earth atmosphere, which is the limiting factor in the interferometer stability. A space interferometer will not suffer from this intrinsic limitations, and can potentially lead to improve astronomical distance measurements by an order of magnitude in precision. We discuss here the technical requirements that a space based facility will need to carry out this project, allowing distance measurements within a few percent accuracy level. We will finally discuss how a sub-milliarcsecond resolution will allow the direct distance determination for hundreds of galactic sources, and provide a substantial improvement in the zero-point of the Cepheid distance scale.

  19. Perspectives of Research on Distance Education.

    ERIC Educational Resources Information Center

    Holmberg, Borje

    The history of research on distance education was studied. Major research done on distance education in such diverse areas as the United States, Venezuela, and Europe was analyzed. It was discovered that the earliest attempts to develop theories of distance education were mainly concerned with identifying its very concept. Like most educational…

  20. Quality Assurance in Distance Learning Libraries

    ERIC Educational Resources Information Center

    Tripathi, Manorama; Jeevan, V. K. J.

    2009-01-01

    Purpose: The paper aims to study how the present distance learning libraries can improve upon their existing services and introduce new ones to enhance quality of services to distance learners. Design/methodology/approach: The paper includes a review of literature on quality assurance in open and distance education in general and student support…

  1. Data Processing Procedures and Methodology for Estimating Trip Distances for the 1995 American Travel Survey (ATS)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hwang, H.-L.; Rollow, J.

    2000-05-01

    The 1995 American Travel Survey (ATS) collected information from approximately 80,000 U.S. households about their long distance travel (one-way trips of 100 miles or more) during the year of 1995. It is the most comprehensive survey of where, why, and how U.S. residents travel since 1977. ATS is a joint effort by the U.S. Department of Transportation (DOT) Bureau of Transportation Statistics (BTS) and the U.S. Department of Commerce Bureau of Census (Census); BTS provided the funding and supervision of the project, and Census selected the samples, conducted interviews, and processed the data. This report documents the technical support formore » the ATS provided by the Center for Transportation Analysis (CTA) in Oak Ridge National Laboratory (ORNL), which included the estimation of trip distances as well as data quality editing and checking of variables required for the distance calculations.« less

  2. Safe Use of Hydrogen and Hydrogen Systems

    NASA Technical Reports Server (NTRS)

    Maes, Miguel

    2006-01-01

    This is a viewgraph presentation that is a course for teaching the safe use of hydrogen. The objectives of the course are 1. To familiarize the student with H2 safety properties 2. To enable the identification, evaluations and addressing of H2 system hazards 3. To teach: a. Safe practices for, b. Design, c. Materials selection, d. H2 system operation, e. Physical principles and empirical observations on which these safe practices are based, f. How to respond to emergency situations involving H2, g How to visualize safety concepts through in-class exercises, h. Identify numerous parameters important to H2 safety.

  3. Dosimetric investigation of LDR brachytherapy ¹⁹²Ir wires by Monte Carlo and TPS calculations.

    PubMed

    Bozkurt, Ahmet; Acun, Hediye; Kemikler, Gonul

    2013-01-01

    The aim of this study was to investigate the dose rate distribution around (192)Ir wires used as radioactive sources in low-dose-rate brachytherapy applications. Monte Carlo modeling of a 0.3-mm diameter source and its surrounding water medium was performed for five different wire lengths (1-5 cm) using the MCNP software package. The computed dose rates per unit of air kerma at distances from 0.1 up to 10 cm away from the source were first verified with literature data sets. Then, the simulation results were compared with the calculations from the XiO CMS commercial treatment planning system. The study results were found to be in concordance with the treatment planning system calculations except for the shorter wires at close distances.

  4. 12 CFR 350.11 - Safe harbor provision.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Safe harbor provision. 350.11 Section 350.11 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY DISCLOSURE OF FINANCIAL AND OTHER INFORMATION BY FDIC-INSURED STATE NONMEMBER BANKS § 350.11 Safe harbor...

  5. A Simple Spreadsheet Program for the Calculation of Lattice-Site Distributions

    ERIC Educational Resources Information Center

    McCaffrey, John G.

    2009-01-01

    A simple spreadsheet program is presented that can be used by undergraduate students to calculate the lattice-site distributions in solids. A major strength of the method is the natural way in which the correct number of ions or atoms are present, or absent, at specific lattice distances. The expanding-cube method utilized is straightforward to…

  6. Breastfeeding Duration and Anogenital Distance in 2-Year-Old Infants.

    PubMed

    Ortega-García, Juan Antonio; Olano-Soler, Henry Andrés; Martínez-Álvarez, Ana; Campillo-López, Ferran; Gomariz-Peñalver, Virtudes; Mendiola-Olivares, Jaime; Iglesias-Gómez, Carlos; Escribano-Muñoz, Arancha

    2016-09-01

    The anogenital distance (AGD) is an anthropometric marker determined by exposures to androgens in utero and throughout the first few months of life. Early exposures to endocrine-disrupting chemicals such as phthalates have been significantly associated with shortened AGD in boys. Limited studies have explored phthalate concentrations in breast milk and infant formula. To explore the associations between breastfeeding duration and AGD measures in infants. MALAMA (Medio Ambiente y Lactancia Materna) is a follow-up study of 430 mother-child pairs, from birth to 2 years, from two population-based cohorts in Murcia, Spain. Data were collected through medical visits and telephone surveys from birth to 2 years of age. World Health Organization breastfeeding definitions were used. AGD measurements were assessed in a subsample of 71 boys and 49 girls at the 2-year visit. Descriptive analyses, Pearson correlations, and linear regressions were calculated between AGD and breastfeeding duration. Duration of all types of breastfeeding, especially full breastfeeding (FB), is correlated with AGD measures in boys (p < 0.05). AGDAS (anoscrotal distance) and AGDAP (anopenile distance) were positively associated with FB (β = 0.004, 95%CI: 0.001-0.007 and β = 0.003, 95%CI: 0.000-0.007, respectively). A positive correlation between AGD in male infants and the duration of breastfeeding is reported. Inversely, early introduction of infant formula could lead to the reduction of AGD in boys.

  7. Analysing designed experiments in distance sampling

    Treesearch

    Stephen T. Buckland; Robin E. Russell; Brett G. Dickson; Victoria A. Saab; Donal N. Gorman; William M. Block

    2009-01-01

    Distance sampling is a survey technique for estimating the abundance or density of wild animal populations. Detection probabilities of animals inherently differ by species, age class, habitats, or sex. By incorporating the change in an observer's ability to detect a particular class of animals as a function of distance, distance sampling leads to density estimates...

  8. Antigenic Distance Measurements for Seasonal Influenza Vaccine Selection

    PubMed Central

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2011-01-01

    Influenza vaccination is one of the major options to counteract the effects of influenza diseases. Selection of an effective vaccine strain is the key to the success of an effective vaccination program since vaccine protection can only be achieved when the selected influenza vaccine strain matches the antigenic variants causing future outbreaks. Identification of an antigenic variant is the first step to determine whether vaccine strain needs to be updated. Antigenic distance derived from immunological assays, such as hemagglutination inhibition, is commonly used to measure the antigenic closeness between circulating strains and the current influenza vaccine strain. Thus, consensus on an explicit and robust antigenic distance measurement is critical in influenza surveillance. Based on the current seasonal influenza surveillance procedure, we propose and compare three antigenic distance measurements, including Average antigenic distance (A-distance), Mutual antigenic distance (M-distance), and Largest antigenic distance (L-distance). With the assistance of influenza antigenic cartography, our simulation results demonstrated that M-distance is a robust influenza antigenic distance measurement. Experimental results on both simulation and seasonal influenza surveillance data demonstrate that M-distance can be effectively utilized in influenza vaccine strain selection. PMID:22063385

  9. Permutation-invariant distance between atomic configurations

    NASA Astrophysics Data System (ADS)

    Ferré, Grégoire; Maillet, Jean-Bernard; Stoltz, Gabriel

    2015-09-01

    We present a permutation-invariant distance between atomic configurations, defined through a functional representation of atomic positions. This distance enables us to directly compare different atomic environments with an arbitrary number of particles, without going through a space of reduced dimensionality (i.e., fingerprints) as an intermediate step. Moreover, this distance is naturally invariant through permutations of atoms, avoiding the time consuming associated minimization required by other common criteria (like the root mean square distance). Finally, the invariance through global rotations is accounted for by a minimization procedure in the space of rotations solved by Monte Carlo simulated annealing. A formal framework is also introduced, showing that the distance we propose verifies the property of a metric on the space of atomic configurations. Two examples of applications are proposed. The first one consists in evaluating faithfulness of some fingerprints (or descriptors), i.e., their capacity to represent the structural information of a configuration. The second application concerns structural analysis, where our distance proves to be efficient in discriminating different local structures and even classifying their degree of similarity.

  10. Microelectromechanical safe arm device

    DOEpatents

    Roesler, Alexander W [Tijeras, NM

    2012-06-05

    Microelectromechanical (MEM) apparatus and methods for operating, for preventing unintentional detonation of energetic components comprising pyrotechnic and explosive materials, such as air bag deployment systems, munitions and pyrotechnics. The MEM apparatus comprises an interrupting member that can be moved to block (interrupt) or complete (uninterrupt) an explosive train that is part of an energetic component. One or more latching members are provided that engage and prevent the movement of the interrupting member, until the one or more latching members are disengaged from the interrupting member. The MEM apparatus can be utilized as a safe and arm device (SAD) and electronic safe and arm device (ESAD) in preventing unintentional detonations. Methods for operating the MEM apparatus include independently applying drive signals to the actuators coupled to the latching members, and an actuator coupled to the interrupting member.

  11. Problems in Defining the Field of Distance Education.

    ERIC Educational Resources Information Center

    Keegan, Desmond

    1988-01-01

    This discussion of definitions of distance education responds to previous articles attempting to define the field. Topics discussed include distance education versus conventional education; group-based distance education; differences between open learning and distance education; and criteria to define distance education. (13 references) (LRW)

  12. Measurement of the "safe zone" and the "dangerous zone" for the screw placement on the quadrilateral surface in the treatment of pelvic and acetabular fractures with Stoppa approach by computational 3D technology.

    PubMed

    Zhang, Sheng; Su, Wanhan; Luo, Qiang; Leung, Frankie; Chen, Bin

    2014-01-01

    This study is aimed at definition of the safe and dangerous zone for screw placement with Stoppa approach for rapid identification during operation and a new way for the studies on the "safe zone." Pelvic CT data of 84 human subjects were recruited to reconstruct the three-dimensional (3D) models. The distances between the edges of the "safe zone," "dangerous zone," and specific anatomic landmarks such as the obturator canal and the pelvic brim were precisely measured, respectively. The results show that the absolute "dangerous zone" was from the pelvic brim to 3.07 cm below it and within 2.86 cm of the obturator canal, while the region 3.56 cm below the pelvic brim or 3.85 cm away from the obturator canal was the absolute "safe zone" for screw placement. The region between the absolute "safe zone" and the absolute "dangerous zone" was the relatively "dangerous zone." As a conclusion, application of computer-assisted 3D modeling techniques aids in the precise measurement of "safe zone" and "dangerous zone" in combination with Stoppa incision. It was not recommended to place screws on the absolute dangerous zone, while, for the relatively "dangerous zone," it depends on the individual variations in bony anatomy and the fracture type.

  13. An interactive distance solution for stroke rehabilitation in the home setting - A feasibility study.

    PubMed

    Palmcrantz, Susanne; Borg, Jörgen; Sommerfeld, Disa; Plantin, Jeanette; Wall, Anneli; Ehn, Maria; Sjölinder, Marie; Boman, Inga-Lill

    2017-09-01

    In this study an interactive distance solution (called the DISKO tool) was developed to enable home-based motor training after stroke. The overall aim was to explore the feasibility and safety of using the DISKO-tool, customized for interactive stroke rehabilitation in the home setting, in different rehabilitation phases after stroke. Fifteen patients in three different stages in the continuum of rehabilitation after stroke participated in a home-based training program using the DISKO-tool. The program included 15 training sessions with recurrent follow-ups by the integrated application for video communication with a physiotherapist. Safety and feasibility were assessed from patients, physiotherapists, and a technician using logbooks, interviews, and a questionnaire. Qualitative content analysis and descriptive statistics were used in the analysis. Fourteen out of 15 patients finalized the training period with a mean of 19.5 minutes spent on training at each session. The DISKO-tool was found to be useful and safe by patients and physiotherapists. This study demonstrates the feasibility and safety of the DISKO-tool and provides guidance in further development and testing of interactive distance technology for home rehabilitation, to be used by health care professionals and patients in different phases of rehabilitation after stroke.

  14. The Gould’s Belt Distances Survey (GOBELINS). III. The Distance to the Serpens/Aquila Molecular Complex

    NASA Astrophysics Data System (ADS)

    Ortiz-León, Gisela N.; Dzib, Sergio A.; Kounkel, Marina A.; Loinard, Laurent; Mioduszewski, Amy J.; Rodríguez, Luis F.; Torres, Rosa M.; Pech, Gerardo; Rivera, Juana L.; Hartmann, Lee; Boden, Andrew F.; Evans, Neal J., II; Briceño, Cesar; Tobin, John J.; Galli, Phillip A. B.

    2017-01-01

    We report on new distances and proper motions to seven stars across the Serpens/Aquila complex. The observations were obtained as part of the Gould’s Belt Distances Survey (GOBELINS) project between 2013 September and 2016 April with the Very Long Baseline Array (VLBA). One of our targets is the proto-Herbig AeBe object EC 95, which is a binary system embedded in the Serpens Core. For this system, we combined the GOBELINS observations with previous VLBA data to cover a total period of 8 years, and derive the orbital elements and an updated source distance. The individual distances to sources in the complex are fully consistent with each other, and the mean value corresponds to a distance of 436.0 ± 9.2 pc for the Serpens/W40 complex. Given this new evidence, we argue that Serpens Main, W40, and Serpens South are physically associated and form a single cloud structure.

  15. Modern Geometric Methods of Distance Determination

    NASA Astrophysics Data System (ADS)

    Thévenin, Frédéric; Falanga, Maurizio; Kuo, Cheng Yu; Pietrzyński, Grzegorz; Yamaguchi, Masaki

    2017-11-01

    Building a 3D picture of the Universe at any distance is one of the major challenges in astronomy, from the nearby Solar System to distant Quasars and galaxies. This goal has forced astronomers to develop techniques to estimate or to measure the distance of point sources on the sky. While most distance estimates used since the beginning of the 20th century are based on our understanding of the physics of objects of the Universe: stars, galaxies, QSOs, the direct measures of distances are based on the geometric methods as developed in ancient Greece: the parallax, which has been applied to stars for the first time in the mid-19th century. In this review, different techniques of geometrical astrometry applied to various stellar and cosmological (Megamaser) objects are presented. They consist in parallax measurements from ground based equipment or from space missions, but also in the study of binary stars or, as we shall see, of binary systems in distant extragalactic sources using radio telescopes. The Gaia mission will be presented in the context of stellar physics and galactic structure, because this key space mission in astronomy will bring a breakthrough in our understanding of stars, galaxies and the Universe in their nature and evolution with time. Measuring the distance to a star is the starting point for an unbiased description of its physics and the estimate of its fundamental parameters like its age. Applying these studies to candles such as the Cepheids will impact our large distance studies and calibration of other candles. The text is constructed as follows: introducing the parallax concept and measurement, we shall present briefly the Gaia satellite which will be the future base catalogue of stellar astronomy in the near future. Cepheids will be discussed just after to demonstrate the state of the art in distance measurements in the Universe with these variable stars, with the objective of 1% of error in distances that could be applied to our closest

  16. Multimedia Equipment for Distance Education.

    ERIC Educational Resources Information Center

    Schiller, Scott S.

    1993-01-01

    Discusses the use of multimedia equipment for distance education. Topics addressed include use of the Internet; distance learning for educators; and cable television and/or fiber optics, including interactive television and satellite technology. A sidebar lists online and telecommunications providers. (LRW)

  17. Dose calculation accuracy of the Monte Carlo algorithm for CyberKnife compared with other commercially available dose calculation algorithms.

    PubMed

    Sharma, Subhash; Ott, Joseph; Williams, Jamone; Dickow, Danny

    2011-01-01

    Monte Carlo dose calculation algorithms have the potential for greater accuracy than traditional model-based algorithms. This enhanced accuracy is particularly evident in regions of lateral scatter disequilibrium, which can develop during treatments incorporating small field sizes and low-density tissue. A heterogeneous slab phantom was used to evaluate the accuracy of several commercially available dose calculation algorithms, including Monte Carlo dose calculation for CyberKnife, Analytical Anisotropic Algorithm and Pencil Beam convolution for the Eclipse planning system, and convolution-superposition for the Xio planning system. The phantom accommodated slabs of varying density; comparisons between planned and measured dose distributions were accomplished with radiochromic film. The Monte Carlo algorithm provided the most accurate comparison between planned and measured dose distributions. In each phantom irradiation, the Monte Carlo predictions resulted in gamma analysis comparisons >97%, using acceptance criteria of 3% dose and 3-mm distance to agreement. In general, the gamma analysis comparisons for the other algorithms were <95%. The Monte Carlo dose calculation algorithm for CyberKnife provides more accurate dose distribution calculations in regions of lateral electron disequilibrium than commercially available model-based algorithms. This is primarily because of the ability of Monte Carlo algorithms to implicitly account for tissue heterogeneities, density scaling functions; and/or effective depth correction factors are not required. Copyright © 2011 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  18. Euclidean chemical spaces from molecular fingerprints: Hamming distance and Hempel's ravens.

    PubMed

    Martin, Eric; Cao, Eddie

    2015-05-01

    Molecules are often characterized by sparse binary fingerprints, where 1s represent the presence of substructures and 0s represent their absence. Fingerprints are especially useful for similarity calculations, such as database searching or clustering, generally measuring similarity as the Tanimoto coefficient. In other cases, such as visualization, design of experiments, or latent variable regression, a low-dimensional Euclidian "chemical space" is more useful, where proximity between points reflects chemical similarity. A temptation is to apply principal components analysis (PCA) directly to these fingerprints to obtain a low dimensional continuous chemical space. However, Gower has shown that distances from PCA on bit vectors are proportional to the square root of Hamming distance. Unlike Tanimoto similarity, Hamming similarity (HS) gives equal weight to shared 0s as to shared 1s, that is, HS gives as much weight to substructures that neither molecule contains, as to substructures which both molecules contain. Illustrative examples show that proximity in the corresponding chemical space reflects mainly similar size and complexity rather than shared chemical substructures. These spaces are ill-suited for visualizing and optimizing coverage of chemical space, or as latent variables for regression. A more suitable alternative is shown to be Multi-dimensional scaling on the Tanimoto distance matrix, which produces a space where proximity does reflect structural similarity.

  19. Distance Measurements In X-Ray Pictures

    NASA Astrophysics Data System (ADS)

    Forsgren, Per-Ola

    1987-10-01

    In this paper, a measurement method for the distance between binary objects will be presented. It has been developed for a specific purpose, the evaluation of rheumatic disease, but should be useful also in other applications. It is based on a distance map in the area between binary objects. A skeleton is extracted from the distance map by searching for local maxima. The distance measure is based on the average of skelton points in a defined measurement area. An objective criterion for selection of measurement points on the skeleton is proposed. Preliminary results indicate that good repeatability is attained.

  20. Quantum algorithms on Walsh transform and Hamming distance for Boolean functions

    NASA Astrophysics Data System (ADS)

    Xie, Zhengwei; Qiu, Daowen; Cai, Guangya

    2018-06-01

    Walsh spectrum or Walsh transform is an alternative description of Boolean functions. In this paper, we explore quantum algorithms to approximate the absolute value of Walsh transform W_f at a single point z0 (i.e., |W_f(z0)|) for n-variable Boolean functions with probability at least 8/π 2 using the number of O(1/|W_f(z_{0)|ɛ }) queries, promised that the accuracy is ɛ , while the best known classical algorithm requires O(2n) queries. The Hamming distance between Boolean functions is used to study the linearity testing and other important problems. We take advantage of Walsh transform to calculate the Hamming distance between two n-variable Boolean functions f and g using O(1) queries in some cases. Then, we exploit another quantum algorithm which converts computing Hamming distance between two Boolean functions to quantum amplitude estimation (i.e., approximate counting). If Ham(f,g)=t≠0, we can approximately compute Ham( f, g) with probability at least 2/3 by combining our algorithm and {Approx-Count(f,ɛ ) algorithm} using the expected number of Θ( √{N/(\\lfloor ɛ t\\rfloor +1)}+√{t(N-t)}/\\lfloor ɛ t\\rfloor +1) queries, promised that the accuracy is ɛ . Moreover, our algorithm is optimal, while the exact query complexity for the above problem is Θ(N) and the query complexity with the accuracy ɛ is O(1/ɛ 2N/(t+1)) in classical algorithm, where N=2n. Finally, we present three exact quantum query algorithms for two promise problems on Hamming distance using O(1) queries, while any classical deterministic algorithm solving the problem uses Ω(2n) queries.