Xue, Fangzheng; Li, Qian; Li, Xiumin
2017-01-01
Recently, echo state network (ESN) has attracted a great deal of attention due to its high accuracy and efficient learning performance. Compared with the traditional random structure and classical sigmoid units, simple circle topology and leaky integrator neurons have more advantages on reservoir computing of ESN. In this paper, we propose a new model of ESN with both circle reservoir structure and leaky integrator units. By comparing the prediction capability on Mackey-Glass chaotic time series of four ESN models: classical ESN, circle ESN, traditional leaky integrator ESN, circle leaky integrator ESN, we find that our circle leaky integrator ESN shows significantly better performance than other ESNs with roughly 2 orders of magnitude reduction of the predictive error. Moreover, this model has stronger ability to approximate nonlinear dynamics and resist noise than conventional ESN and ESN with only simple circle structure or leaky integrator neurons. Our results show that the combination of circle topology and leaky integrator neurons can remarkably increase dynamical diversity and meanwhile decrease the correlation of reservoir states, which contribute to the significant improvement of computational performance of Echo state network on time series prediction.
Bounds of the error of Gauss-Turan-type quadratures
NASA Astrophysics Data System (ADS)
Milovanovic, Gradimir V.; Spalevic, Miodrag M.
2005-06-01
We consider the remainder term of the Gauss-Turan quadrature formulaefor analytic functions in some region of the complex plane containing the interval [-1,1] in its interior. The remainder term is presented in the form of a contour integral over confocal ellipses or circles. A strong error analysis is given for the case with a generalized class of weight functions, introduced recently by Gori and Micchelli. Also, we discuss a general case with an even weight function defined on [-1,1]. Numerical results are included.
A Survey of Terrain Modeling Technologies and Techniques
2007-09-01
Washington , DC 20314-1000 ERDC/TEC TR-08-2 ii Abstract: Test planning, rehearsal, and distributed test events for Future Combat Systems (FCS) require...distance) for all five lines of control points. Blue circles are errors of DSM (original data), red squares are DTM (bare Earth, processed by Intermap...circles are DSM, red squares are DTM ........... 8 5 Distribution of errors for line No. 729. Blue circles are DSM, red squares are DTM
The effects of errors on children's performance on a circle-ellipse discrimination.
Stoddard, L T; Sidman, M
1967-05-01
Children first learned by means of a teaching program to discriminate a circle from relatively flat ellipses. Children in the control group then proceeded into a program which gradually reduced the difference between the circle and the ellipses. They advanced to a finer discrimination when they made a correct choice, and reversed to an easier discrimination after making errors ("backup" procedure). The children made relatively few errors until they approached the region of their difference threshold (empirically determined under the conditions described). When they could no longer discriminate the forms, they learned other bases for responding that could be classified as specifiable error patterns. Children in the experimental group, having learned the preliminary circle-ellipse discrimination, were started at the upper end of the ellipse series, where it was impossible for them to discriminate the forms. The backup procedure returned them to an easier discrimination after they made errors. They made many errors and reversed down through the ellipse series. Eventually, most of the children reached a point in the ellipse series where they abandoned their systematic errors and began to make correct first choices; then they advanced upward through the program. All of the children advanced to ellipse sizes that were much larger than the ellipse size at the point of their furthest descent.
Restoration of the ASCA Source Position Accuracy
NASA Astrophysics Data System (ADS)
Gotthelf, E. V.; Ueda, Y.; Fujimoto, R.; Kii, T.; Yamaoka, K.
2000-11-01
We present a calibration of the absolute pointing accuracy of the Advanced Satellite for Cosmology and Astrophysics (ASCA) which allows us to compensate for a large error (up to 1') in the derived source coordinates. We parameterize a temperature dependent deviation of the attitude solution which is responsible for this error. By analyzing ASCA coordinates of 100 bright active galactic nuclei, we show that it is possible to reduce the uncertainty in the sky position for any given observation by a factor of 4. The revised 90% error circle radius is then 12", consistent with preflight specifications, effectively restoring the full ASCA pointing accuracy. Herein, we derive an algorithm which compensates for this attitude error and present an internet-based table to be used to correct post facto the coordinate of all ASCA observations. While the above error circle is strictly applicable to data taken with the on-board Solid-state Imaging Spectrometers (SISs), similar coordinate corrections are derived for data obtained with the Gas Imaging Spectrometers (GISs), which, however, have additional instrumental uncertainties. The 90% error circle radius for the central 20' diameter of the GIS is 24". The large reduction in the error circle area for the two instruments offers the opportunity to greatly enhance the search for X-ray counterparts at other wavelengths. This has important implications for current and future ASCA source catalogs and surveys.
Swift follow-up of 1RXS J194211.9+255552
NASA Astrophysics Data System (ADS)
Sidoli, L.; Fiocchi, M.; Bird, A. J.; Drave, S. P.; Bazzano, A.; Persi, P.; Tarana, A.; Sguera, V.; Chenevez, J.; Kuulkers, E.
2011-12-01
Following the INTEGRAL/JEM-X detection of the unidentified source 1RXS J194211.9+255552 (ATel #3816) on December 18, we asked for a Swift/XRT follow-up observation. Swift observed the source field on December 21, 2011 at 06:10:09.7 (UTC), with a net exposure of 1756 s. Within the ROSAT error circle there is only one pointlike source, at the following position (J2000): RA(hh mm ss.s) = 19h42m11.13s, Dec(dd mm ss.s) = +25:56:07.32 (3.6 arcsec error radius).
Reducing representativeness and sampling errors in radio occultation-radiosonde comparisons
NASA Astrophysics Data System (ADS)
Gilpin, Shay; Rieckh, Therese; Anthes, Richard
2018-05-01
Radio occultation (RO) and radiosonde (RS) comparisons provide a means of analyzing errors associated with both observational systems. Since RO and RS observations are not taken at the exact same time or location, temporal and spatial sampling errors resulting from atmospheric variability can be significant and inhibit error analysis of the observational systems. In addition, the vertical resolutions of RO and RS profiles vary and vertical representativeness errors may also affect the comparison. In RO-RS comparisons, RO observations are co-located with RS profiles within a fixed time window and distance, i.e. within 3-6 h and circles of radii ranging between 100 and 500 km. In this study, we first show that vertical filtering of RO and RS profiles to a common vertical resolution reduces representativeness errors. We then test two methods of reducing horizontal sampling errors during RO-RS comparisons: restricting co-location pairs to within ellipses oriented along the direction of wind flow rather than circles and applying a spatial-temporal sampling correction based on model data. Using data from 2011 to 2014, we compare RO and RS differences at four GCOS Reference Upper-Air Network (GRUAN) RS stations in different climatic locations, in which co-location pairs were constrained to a large circle ( ˜ 666 km radius), small circle ( ˜ 300 km radius), and ellipse parallel to the wind direction ( ˜ 666 km semi-major axis, ˜ 133 km semi-minor axis). We also apply a spatial-temporal sampling correction using European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim) gridded data. Restricting co-locations to within the ellipse reduces root mean square (RMS) refractivity, temperature, and water vapor pressure differences relative to RMS differences within the large circle and produces differences that are comparable to or less than the RMS differences within circles of similar area. Applying the sampling correction shows the most significant reduction in RMS differences, such that RMS differences are nearly identical to the sampling correction regardless of the geometric constraints. We conclude that implementing the spatial-temporal sampling correction using a reliable model will most effectively reduce sampling errors during RO-RS comparisons; however, if a reliable model is not available, restricting spatial comparisons to within an ellipse parallel to the wind flow will reduce sampling errors caused by horizontal atmospheric variability.
Discovery of a Be/X-Ray Binary Consistent with the Location of GRO J2058+42
NASA Technical Reports Server (NTRS)
Wilson, Colleen; Weisskopf, Martin; Finger, Mark H.; Coe, M. J.; Greiner, Jochen; Reig, Pablo; Papamastorakis, Giannis
2005-01-01
GRO J2058+42 is a 195 s transient X-ray pulsar discovered in 1995 with BATSE. In 1996, RXTE located GRO J2058+42 to a 90% confidence error circle with a 4 radius. On 2004 February 20, the region including the error circle was observed with Chandra ACIS-I. No X-ray sources were detected within the error circle; however, two faint sources were detected in the ACIS-I field of view. We obtained optical observations of the brightest object, CXOU J205847.5+414637, which had about 64 X-ray counts and was just 013 outside the error circle. The optical spectrum contains a strong Ha line and corresponds to an inhued object in the Two Micron All Sky Survey catalog, indicating a Be/X-ray binary system. Pulsations were not detected in the Chandra observations, but similar flux variations and distance estimates suggest that CXOU J205847.5+414637 and GRO J2058+42 are the same object. We present results from the Chandra observation, optical observations, new and previously unreported RXTE observations, and a reanalysis of a ROSAT observation.
Quasi-eccentricity error modeling and compensation in vision metrology
NASA Astrophysics Data System (ADS)
Shen, Yijun; Zhang, Xu; Cheng, Wei; Zhu, Limin
2018-04-01
Circular targets are commonly used in vision applications for its detection accuracy and robustness. The eccentricity error of the circular target caused by perspective projection is one of the main factors of measurement error which needs to be compensated in high-accuracy measurement. In this study, the impact of the lens distortion on the eccentricity error is comprehensively investigated. The traditional eccentricity error turns to a quasi-eccentricity error in the non-linear camera model. The quasi-eccentricity error model is established by comparing the quasi-center of the distorted ellipse with the true projection of the object circle center. Then, an eccentricity error compensation framework is proposed which compensates the error by iteratively refining the image point to the true projection of the circle center. Both simulation and real experiment confirm the effectiveness of the proposed method in several vision applications.
A Novel Attitude Estimation Algorithm Based on the Non-Orthogonal Magnetic Sensors
Zhu, Jianliang; Wu, Panlong; Bo, Yuming
2016-01-01
Because the existing extremum ratio method for projectile attitude measurement is vulnerable to random disturbance, a novel integral ratio method is proposed to calculate the projectile attitude. First, the non-orthogonal measurement theory of the magnetic sensors is analyzed. It is found that the projectile rotating velocity is constant in one spinning circle and the attitude error is actually the pitch error. Next, by investigating the model of the extremum ratio method, an integral ratio mathematical model is established to improve the anti-disturbance performance. Finally, by combining the preprocessed magnetic sensor data based on the least-square method and the rotating extremum features in one cycle, the analytical expression of the proposed integral ratio algorithm is derived with respect to the pitch angle. The simulation results show that the proposed integral ratio method gives more accurate attitude calculations than does the extremum ratio method, and that the attitude error variance can decrease by more than 90%. Compared to the extremum ratio method (which collects only a single data point in one rotation cycle), the proposed integral ratio method can utilize all of the data collected in the high spin environment, which is a clearly superior calculation approach, and can be applied to the actual projectile environment disturbance. PMID:27213389
NASA Astrophysics Data System (ADS)
Nemiro, A. A.
The opticomechanical scheme of a pentag meridian circle is presented. The central rotating part of the instrument, made of sitall (cer-vit), is compact and uniform, making it possible to minimize the gravitational and thermal deformations. It is shown that variations of the orientation of the central part do not affect observations because of the use of the pentag. Formulas are presented for determining the collimation error and zero point of the circle using autocollimation readings.
Optimization of Aimpoints for Coordinate Seeking Weapons
2015-09-01
aiming) and independent ( ballistic ) errors are taken into account, before utilizing each of the three damage functions representing the weapon. A Monte...characteristics such as the radius of the circle containing the weapon aimpoint, impact angle, dependent (aiming) and independent ( ballistic ) errors are taken...Dependent (Aiming) Error .................................8 2. Single Weapon Independent ( Ballistic ) Error .............................9 3
Saidi, Maryam; Towhidkhah, Farzad; Gharibzadeh, Shahriar; Lari, Abdolaziz Azizi
2013-12-01
Humans perceive the surrounding world by integration of information through different sensory modalities. Earlier models of multisensory integration rely mainly on traditional Bayesian and causal Bayesian inferences for single causal (source) and two causal (for two senses such as visual and auditory systems), respectively. In this paper a new recurrent neural model is presented for integration of visual and proprioceptive information. This model is based on population coding which is able to mimic multisensory integration of neural centers in the human brain. The simulation results agree with those achieved by casual Bayesian inference. The model can also simulate the sensory training process of visual and proprioceptive information in human. Training process in multisensory integration is a point with less attention in the literature before. The effect of proprioceptive training on multisensory perception was investigated through a set of experiments in our previous study. The current study, evaluates the effect of both modalities, i.e., visual and proprioceptive training and compares them with each other through a set of new experiments. In these experiments, the subject was asked to move his/her hand in a circle and estimate its position. The experiments were performed on eight subjects with proprioception training and eight subjects with visual training. Results of the experiments show three important points: (1) visual learning rate is significantly more than that of proprioception; (2) means of visual and proprioceptive errors are decreased by training but statistical analysis shows that this decrement is significant for proprioceptive error and non-significant for visual error, and (3) visual errors in training phase even in the beginning of it, is much less than errors of the main test stage because in the main test, the subject has to focus on two senses. The results of the experiments in this paper is in agreement with the results of the neural model simulation.
Easing The Calculation Of Bolt-Circle Coordinates
NASA Technical Reports Server (NTRS)
Burley, Richard K.
1995-01-01
Bolt Circle Calculation (BOLT-CALC) computer program used to reduce significant time consumed in manually computing trigonometry of rectangular Cartesian coordinates of holes in bolt circle as shown on blueprint or drawing. Eliminates risk of computational errors, particularly in cases involving many holes or in cases in which coordinates expressed to many significant digits. Program assists in many practical situations arising in machine shops. Written in BASIC. Also successfully compiled and implemented by use of Microsoft's QuickBasic v4.0.
NASA Astrophysics Data System (ADS)
Yang, Fan; Du, Zhengchun; Yang, Jiangguo; Hong, Maisheng
2011-12-01
Geometric motion error measurement has been considered as an important task for accuracy enhancement and quality assurance of NC machine tools and CMMs. In consideration of the disadvantages of traditional measuring methods,a new measuring method for motion accuracy of 3-axis NC equipments based on composite trajectory including circle and non-circle(straight line and/or polygonal line) is proposed. The principles and techniques of the new measuring method are discussed in detail. 8 feasible measuring strategies based on different measuring groupings are summarized and optimized. The experiment of the most preferable strategy is carried out on the 3-axis CNC vertical machining center Cincinnati 750 Arrow by using cross grid encoder. The whole measuring time of 21 error components of the new method is cut down to 1-2 h because of easy installation, adjustment, operation and the characteristics of non-contact measurement. Result shows that the new method is suitable for `on machine" measurement and has good prospects of wide application.
Optical identification of IGR J18308-1232 as a Cataclysmic Variable
NASA Astrophysics Data System (ADS)
Parisi, P.; Masetti, N.; Jimenez, E.; Chavushyan, V.; Bassani, L.; Bazzano, A.; Bird, A. J.
2008-09-01
We report on a spectroscopic analysis of optical sources inside the error circle of the XMM-Newton slew source XMMLS1 J183049.6-123218 (see Ibarra et al., ATel #1527), associated with the unidentified INTEGRAL source IGR J18308-1232 (Bird et al. 2007, ApJS, 170, 175). The observations were performed on 2008 June 28, starting at 06:37 UT, with the Boller & Chivens spectrograph mounted on the 2.1m telescope of the Observatorio Astronomico Nacional (San Pedro Martir, Baja California, Mexico), for a total exposure time of 7200 s.
Error Pattern Analysis Applied to Technical Writing: An Editor's Guide for Writers.
ERIC Educational Resources Information Center
Monagle, E. Brette
The use of error pattern analysis can reduce the time and money spent on editing and correcting manuscripts. What is required is noting, classifying, and keeping a frequency count of errors. First an editor should take a typical page of writing and circle each error. After the editor has done a sufficiently large number of pages to identify an…
Optical spectroscopic followup of XMMSL1 J164303.7+653253 in the error box of IGR J16426+6536
NASA Astrophysics Data System (ADS)
Parisi, P.; Masetti, N.; Malizia, A.; Morelli, L.; Mason, E.; Dean, A. J.; Ubertini, P.
2008-10-01
We report on a spectroscopic observation of the optical object USNO-A2.0 1500-06133361 (with J2000 coordinates RA = 16 43 04.07, Dec = +65 32 50.9 and magnitude R ~ 18.9) inside the error circle of the XMM-Newton slew source XMMLS1 J164303.7+653253 (see Ibarra et al., ATel #1397), possibly associated with the unidentified INTEGRAL source IGR J16426+6536 (Bird et al. 2007, ApJS, 170, 175). The observations were performed on 2008 February 04, starting at 06:10 UT, with DOLORES, a focal reducer instrument installed on the 3.58m Telescopio Nazionale Galileo (TNG) in the Astronomical Observatory of Roque de Los Muchachos (Santa Cruz de La Palma, Spain), for a total exposure time of 1800 s.
Reflectively Coupled Waveguide Photodetector for High Speed Optical Interconnection
Hsu*, Shih-Hsiang
2010-01-01
To fully utilize GaAs high drift mobility, techniques to monolithically integrate In0.53Ga0.47As p-i-n photodetectors with GaAs based optical waveguides using total internal reflection coupling are reviewed. Metal coplanar waveguides, deposited on top of the polyimide layer for the photodetector’s planarization and passivation, were then uniquely connected as a bridge between the photonics and electronics to illustrate the high-speed monitoring function. The photodetectors were efficiently implemented and imposed on the echelle grating circle for wavelength division multiplexing monitoring. In optical filtering performance, the monolithically integrated photodetector channel spacing was 2 nm over the 1,520–1,550 nm wavelength range and the pass band was 1 nm at the −1 dB level. For high-speed applications the full-width half-maximum of the temporal response and 3-dB bandwidth for the reflectively coupled waveguide photodetectors were demonstrated to be 30 ps and 11 GHz, respectively. The bit error rate performance of this integrated photodetector at 10 Gbit/s with 27-1 long pseudo-random bit sequence non-return to zero input data also showed error-free operation. PMID:22163502
NASA Technical Reports Server (NTRS)
Ukwatta, T. N.; Linnemann, J. T.; Tollefson, K.; Abeysekara, A. U.; Bhat, P. N.; Sonbas, E.; Gehrels, N.
2011-01-01
We investigate the feasibility of implementing a system that will coordinate ground-based optical telescopes to cover the Fermi GBM Error Circle (EC). The aim of the system is to localize GBM detected GRBs and facilitate multi-wavelength follow-up from space and ground. This system will optimize the observing locations in the GBM EC based on individual telescope location, Field of View (FoV) and sensitivity. The proposed system will coordinate GBM EC scanning by professional as well as amateur astronomers around the world. The results of a Monte Carlo simulation to investigate the feasibility of the project are presented.
One-step random mutagenesis by error-prone rolling circle amplification
Fujii, Ryota; Kitaoka, Motomitsu; Hayashi, Kiyoshi
2004-01-01
In vitro random mutagenesis is a powerful tool for altering properties of enzymes. We describe here a novel random mutagenesis method using rolling circle amplification, named error-prone RCA. This method consists of only one DNA amplification step followed by transformation of the host strain, without treatment with any restriction enzymes or DNA ligases, and results in a randomly mutated plasmid library with 3–4 mutations per kilobase. Specific primers or special equipment, such as a thermal-cycler, are not required. This method permits rapid preparation of randomly mutated plasmid libraries, enabling random mutagenesis to become a more commonly used technique. PMID:15507684
A High-Precision Instrument for Mapping of Rotational Errors in Rotary Stages
Xu, W.; Lauer, K.; Chu, Y.; ...
2014-11-02
A rotational stage is a key component of every X-ray instrument capable of providing tomographic or diffraction measurements. To perform accurate three-dimensional reconstructions, runout errors due to imperfect rotation (e.g. circle of confusion) must be quantified and corrected. A dedicated instrument capable of full characterization and circle of confusion mapping in rotary stages down to the sub-10 nm level has been developed. A high-stability design, with an array of five capacitive sensors, allows simultaneous measurements of wobble, radial and axial displacements. The developed instrument has been used for characterization of two mechanical stages which are part of an X-ray microscope.
Implementing Material Surfaces with an Adhesive Switch
2014-02-28
squares), M15 (solid triangles), M13 (open circles), M11 (solid circles), or NC14 (open triangles) DNA primary targets. Error bars indicating...5’–ATCAGGCGCAA–3’ M13 = 5’–ATCAGCGGCAATC–3’ M15 = 5’–ATCAGCCCCAATCCA–3’ L3M9 = 5’–ATLCACLCCGLC–3’ L3M11 = 5
Statistics of the residual refraction errors in laser ranging data
NASA Technical Reports Server (NTRS)
Gardner, C. S.
1977-01-01
A theoretical model for the range error covariance was derived by assuming that the residual refraction errors are due entirely to errors in the meteorological data which are used to calculate the atmospheric correction. The properties of the covariance function are illustrated by evaluating the theoretical model for the special case of a dense network of weather stations uniformly distributed within a circle.
A multiloop generalization of the circle criterion for stability margin analysis
NASA Technical Reports Server (NTRS)
Safonov, M. G.; Athans, M.
1979-01-01
In order to provide a theoretical tool suited for characterizing the stability margins of multiloop feedback systems, multiloop input-output stability results generalizing the circle stability criterion are considered. Generalized conic sectors with 'centers' and 'radii' determined by linear dynamical operators are employed to specify the stability margins as a frequency dependent convex set of modeling errors (including nonlinearities, gain variations and phase variations) which the system must be able to tolerate in each feedback loop without instability. The resulting stability criterion gives sufficient conditions for closed loop stability in the presence of frequency dependent modeling errors, even when the modeling errors occur simultaneously in all loops. The stability conditions yield an easily interpreted scalar measure of the amount by which a multiloop system exceeds, or falls short of, its stability margin specifications.
OD Covariance in Conjunction Assessment: Introduction and Issues
NASA Technical Reports Server (NTRS)
Hejduk, M. D.; Duncan, M.
2015-01-01
Primary and secondary covariances combined and projected into conjunction plane (plane perpendicular to relative velocity vector at TCA) Primary placed on x-axis at (miss distance, 0) and represented by circle of radius equal to sum of both spacecraft circumscribing radiiZ-axis perpendicular to x-axis in conjunction plane Pc is portion of combined error ellipsoid that falls within the hard-body radius circle
Measuring Diameters Of Large Vessels
NASA Technical Reports Server (NTRS)
Currie, James R.; Kissel, Ralph R.; Oliver, Charles E.; Smith, Earnest C.; Redmon, John W., Sr.; Wallace, Charles C.; Swanson, Charles P.
1990-01-01
Computerized apparatus produces accurate results quickly. Apparatus measures diameter of tank or other large cylindrical vessel, without prior knowledge of exact location of cylindrical axis. Produces plot of inner circumference, estimate of true center of vessel, data on radius, diameter of best-fit circle, and negative and positive deviations of radius from circle at closely spaced points on circumference. Eliminates need for time-consuming and error-prone manual measurements.
Variable mid-latitude X-ray source 3U 0042+32
NASA Technical Reports Server (NTRS)
Rappaport, S.; Clark, G. W.; Dower, R.; Doxsey, R.; Jernigan, G.; Li, F.
1977-01-01
A celestial location with an error circle of radius one minute is reported for the mid-latitude X-ray source 3U 0042+32; comparison of observations from the Ariel-5 and Uhuru satellites with data obtained from two independent rotation modulation collimators yields the precise position. Studies to detect regular pulsations and energy spectra of the X-ray source are also discussed. Analysis of the peak X-ray flux in the error circle, as well as certain distance constraints, suggests that the source of the flux may be a neutron star in a distant galactic binary system having a companion that undergoes episodes of mass transfer due to eruption or orbital eccentricity.
Huang, Junhui; Xue, Qi; Wang, Zhao; Gao, Jianmin
2016-09-03
While color-coding methods have improved the measuring efficiency of a structured light three-dimensional (3D) measurement system, they decreased the measuring accuracy significantly due to lateral chromatic aberration (LCA). In this study, the LCA in a structured light measurement system is analyzed, and a method is proposed to compensate the error caused by the LCA. Firstly, based on the projective transformation, a 3D error map of LCA is constructed in the projector images by using a flat board and comparing the image coordinates of red, green and blue circles with the coordinates of white circles at preselected sample points within the measurement volume. The 3D map consists of the errors, which are the equivalent errors caused by LCA of the camera and projector. Then in measurements, error values of LCA are calculated and compensated to correct the projector image coordinates through the 3D error map and a tri-linear interpolation method. Eventually, 3D coordinates with higher accuracy are re-calculated according to the compensated image coordinates. The effectiveness of the proposed method is verified in the following experiments.
Huang, Junhui; Xue, Qi; Wang, Zhao; Gao, Jianmin
2016-01-01
While color-coding methods have improved the measuring efficiency of a structured light three-dimensional (3D) measurement system, they decreased the measuring accuracy significantly due to lateral chromatic aberration (LCA). In this study, the LCA in a structured light measurement system is analyzed, and a method is proposed to compensate the error caused by the LCA. Firstly, based on the projective transformation, a 3D error map of LCA is constructed in the projector images by using a flat board and comparing the image coordinates of red, green and blue circles with the coordinates of white circles at preselected sample points within the measurement volume. The 3D map consists of the errors, which are the equivalent errors caused by LCA of the camera and projector. Then in measurements, error values of LCA are calculated and compensated to correct the projector image coordinates through the 3D error map and a tri-linear interpolation method. Eventually, 3D coordinates with higher accuracy are re-calculated according to the compensated image coordinates. The effectiveness of the proposed method is verified in the following experiments. PMID:27598174
Introducing Nine-Point Circle to Junior High School Students
NASA Astrophysics Data System (ADS)
Fiangga, S.; Azizah, M. A. N.; Rini, R. N. K.; Hidayanti, A. N.
2018-01-01
The concept of circles is an ancient concept that has appeared since Ancient Egypt from which this concept gives many significant contributions in mathematics’ development until now. Nevertheless, the concept of circles hides many uncover mysterious features that are of applications in mathematics. One of the mysterious features is the Nine-Point Circle. This Nine-point circle is also known as Euler’s circle, six-point circle, Feuerbach’s circle, the twelve-point circle, and many others. Because of these different names, there have been misunderstand among mathematicians about the Nine-Point Circle’s history. Besides, the discussion of Nine-Point Circle can be used to be an initial material to explain elementary geometry topic in junior high school’s level curriculum of 2013. Therefore, this concept needs to be delivered to the students as a geometry introduction. A possible form of the integration historical aspect of Nine-point circle is suggested in this paper as well as its importance in the curriculum of 2013.
Kim, Jong-Ahn; Kim, Jae Wan; Kang, Chu-Shik; Jin, Jonghan; Eom, Tae Bong
2011-11-01
We present an angle generator with high resolution and accuracy, which uses multiple ultrasonic motors and a self-calibratable encoder. A cylindrical air bearing guides a rotational motion, and the ultrasonic motors achieve high resolution over the full circle range with a simple configuration. The self-calibratable encoder can compensate the scale error of a divided circle (signal period: 20") effectively by applying the equal-division-averaged method. The angle generator configures a position feedback control loop using the readout of the encoder. By combining the ac and dc operation mode, the angle generator produced stepwise angular motion with 0.005" resolution. We also evaluated the performance of the angle generator using a precision angle encoder and an autocollimator. The expanded uncertainty (k = 2) in the angle generation was estimated less than 0.03", which included the calibrated scale error and the nonlinearity error. © 2011 American Institute of Physics
NASA Technical Reports Server (NTRS)
Schlegel, E.; Norris, Jay P. (Technical Monitor)
2002-01-01
This project was awarded funding from the CGRO program to support ROSAT and ground-based observations of unidentified sources from data obtained by the EGRET instrument on the Compton Gamma-Ray Observatory. The critical items in the project are the individual ROSAT observations that are used to cover the 99% error circle of the unidentified EGRET source. Each error circle is a degree or larger in diameter. Each ROSAT field is about 30 deg in diameter. Hence, a number (>4) of ROSAT pointings must be obtained for each EGRET source to cover the field. The scheduling of ROSAT observations is carried out to maximize the efficiency of the total schedule. As a result, each pointing is broken into one or more sub-pointings of various exposure times. This project was awarded ROSAT observing time for four unidentified EGRET sources, summarized in the table. The column headings are defined as follows: 'Coverings' = number of observations to cover the error circle; 'SubPtg' = total number of sub-pointings to observe all of the coverings; 'Rec'd' = number of individual sub-pointings received to date; 'CompFlds' = number of individual coverings for which the requested complete exposure has been received. Processing of the data can not occur until a complete exposure has been accumulated for each covering.
Integrating Literature Circles into a Cotaught Inclusive Classroom
ERIC Educational Resources Information Center
Whittaker, Catharine R.
2012-01-01
Literature circles or book clubs are small, heterogeneous groups of students who have chosen to read and discuss the same book together. The research on literature circles suggests that they hold great promise for increasing students' enjoyment of reading and honing their literacy skills. When evidence-based strategies are embedded into a…
Bymixer system can measure O2 uptake and CO2 elimination in the anesthesia circle circuit.
Rosenbaum, Abraham; Kirby, Christopher W; Breen, Peter H
2007-06-01
The ability to measure carbon dioxide elimination (Vco(2)), oxygen uptake (Vo(2)), and R (respiratory exchange ratio, Vco(2)/Vo(2)) during anesthesia may help the non-invasive detection of critical events (e.g., abrupt decrease in cardiac output) and metabolic upset (e.g., onset of anaerobic metabolism). We have developed a new clinical bymixer (inline mixing chamber) that can measure mixed inspired and expired gas fractions in the anesthesia circle circuit. The addition of a standard anesthesia gas analyzer and flowmeter, and a new airway temperature and humidity sensor, allow determinations of Vco(2) and Vo(2) at the airway opening of the circle circuit. Over a range of tidal volume and frequency, Vco(2) and Vo(2) were compared to reference values generated by the combustion of metered liquid ethanol in a new metabolic lung simulator. By linear regression, bymixer-flow measurements of Vco(2) (slope = 1.02, Y-intercept = -5.31, coefficient of determination, R(2) = 0.998) and Vo(2) (slope = 1.05, Y-intercept = -4.34, R(2) = 0.993) correlated closely to the reference values generated by the metabolic lung simulator. Limits of agreement analysis generated percent errors (mean +/- 1.96 SD) of -1.2 +/- 7.2% for Vco(2) and 2.5 +/- 9.8% for Vo(2). The new clinical bymixer is compact, lightweight, disposable, inexpensive, and has a fast and adjustable response time (time constant about 14 sec). Anesthesia circle circuit integrity is maintained. Bymixer-flow measurements of Vco(2) and Vo(2) are accurate and may add to clinical monitoring under anesthesia and surgery.
Reactivation of Chromosomally Integrated Human Herpesvirus-6 by Telomeric Circle Formation
Prusty, Bhupesh K.; Krohne, George; Rudel, Thomas
2013-01-01
More than 95% of the human population is infected with human herpesvirus-6 (HHV-6) during early childhood and maintains latent HHV-6 genomes either in an extra-chromosomal form or as a chromosomally integrated HHV-6 (ciHHV-6). In addition, approximately 1% of humans are born with an inheritable form of ciHHV-6 integrated into the telomeres of chromosomes. Immunosuppression and stress conditions can reactivate latent HHV-6 replication, which is associated with clinical complications and even death. We have previously shown that Chlamydia trachomatis infection reactivates ciHHV-6 and induces the formation of extra-chromosomal viral DNA in ciHHV-6 cells. Here, we propose a model and provide experimental evidence for the mechanism of ciHHV-6 reactivation. Infection with Chlamydia induced a transient shortening of telomeric ends, which subsequently led to increased telomeric circle (t-circle) formation and incomplete reconstitution of circular viral genomes containing single viral direct repeat (DR). Correspondingly, short t-circles containing parts of the HHV-6 DR were detected in cells from individuals with genetically inherited ciHHV-6. Furthermore, telomere shortening induced in the absence of Chlamydia infection also caused circularization of ciHHV-6, supporting a t-circle based mechanism for ciHHV-6 reactivation. PMID:24367281
The Whole Warps the Sum of Its Parts.
Corbett, Jennifer E
2017-01-01
The efficiency of averaging properties of sets without encoding redundant details is analogous to gestalt proposals that perception is parsimoniously organized as a function of recurrent order in the world. This similarity suggests that grouping and averaging are part of a broader set of strategies allowing the visual system to circumvent capacity limitations. To examine how gestalt grouping affects the manner in which information is averaged and remembered, I compared the error in observers' adjustments of remembered sizes of individual circles in two different mean-size sets defined by similarity, proximity, connectedness, or a common region. Overall, errors were more similar within the same gestalt-defined groups than between different gestalt-defined groups, such that the remembered sizes of individual circles were biased toward the mean size of their respective gestalt-defined groups. These results imply that gestalt grouping facilitates perceptual averaging to minimize the error with which individual items are encoded, thereby optimizing the efficiency of visual short-term memory.
Dörnberger, V; Dörnberger, G
1987-01-01
On 99 testes of corpses (death had occurred between 26 und 86 years) comparative volumetry was done. In the left surrounding capsules (without scrotal skin and tunica dartos) the testes were measured via real time sonography in a waterbath (7.5 MHz linear-scan), afterwards length, breadth and height were measured by a sliding calibre, the largest diameter (the length) of the testis was determined by Schirren's circle and finally the size of the testis was measured via Prader's orchidometer. After all the testes were surgically exposed, their volume (by litres) was determined according to Archimedes' principle. As for the Archimedes' principle a random mean error of 7% must be accepted, sonographic determination of the volume showed a random mean error of 15%. Whereas the accuracy of measurement increases with increasing volumes, both methods should be used with caution if the volumes are below 4 ml, since the possibilities of error are rather great. According to Prader's orchidometer the measured volumes on average were higher (+ 27%) with a random mean error of 19.5%. With Schirren's circle the obtained mean value was even higher (+ 52%) in comparison to the "real" volume by Archimedes' principle with a random mean error of 19%. The measurements of the testes in the left capsules by sliding calibre can be optimized, if one applies a correcting factor f (sliding calibre) = 0.39 for calculation of the testis volume corresponding to an ellipsoid. Here you will get the same mean value as in Archimedes' principle with a standard mean error of only 9%. If one applies the correction factor of real time sonography of testis f (sono) = 0.65 the mean value of sliding calibre measurements would be 68.8% too high with a standard mean error of 20.3%. For measurements via sliding calibre the calculation of the testis volume corresponding to an ellipsoid one should apply the smaller factor f (sliding calibre) = 0.39, because in this way the left capsules of testis and the epididymis are considered.
Kitson, Nicole A; Price, Morgan; Lau, Francis Y; Showler, Grey
2013-10-17
Medication errors are a common type of preventable errors in health care causing unnecessary patient harm, hospitalization, and even fatality. Improving communication between providers and between providers and patients is a key aspect of decreasing medication errors and improving patient safety. Medication management requires extensive collaboration and communication across roles and care settings, which can reduce (or contribute to) medication-related errors. Medication management involves key recurrent activities (determine need, prescribe, dispense, administer, and monitor/evaluate) with information communicated within and between each. Despite its importance, there is a lack of conceptual models that explore medication communication specifically across roles and settings. This research seeks to address that gap. The Circle of Care Modeling (CCM) approach was used to build a model of medication communication activities across the circle of care. CCM positions the patient in the centre of his or her own healthcare system; providers and other roles are then modeled around the patient as a web of relationships. Recurrent medication communication activities were mapped to the medication management framework. The research occurred in three iterations, to test and revise the model: Iteration 1 consisted of a literature review and internal team discussion, Iteration 2 consisted of interviews, observation, and a discussion group at a Community Health Centre, and Iteration 3 consisted of interviews and a discussion group in the larger community. Each iteration provided further detail to the Circle of Care medication communication model. Specific medication communication activities were mapped along each communication pathway between roles and to the medication management framework. We could not map all medication communication activities to the medication management framework; we added Coordinate as a separate and distinct recurrent activity. We saw many examples of coordination activities, for instance, Medical Office Assistants acting as a liaison between pharmacists and family physicians to clarify prescription details. Through the use of CCM we were able to unearth tacitly held knowledge to expand our understanding of medication communication. Drawing out the coordination activities could be a missing piece for us to better understand how to streamline and improve multi-step communication processes with a goal of improving patient safety.
2013-01-01
Background Medication errors are a common type of preventable errors in health care causing unnecessary patient harm, hospitalization, and even fatality. Improving communication between providers and between providers and patients is a key aspect of decreasing medication errors and improving patient safety. Medication management requires extensive collaboration and communication across roles and care settings, which can reduce (or contribute to) medication-related errors. Medication management involves key recurrent activities (determine need, prescribe, dispense, administer, and monitor/evaluate) with information communicated within and between each. Despite its importance, there is a lack of conceptual models that explore medication communication specifically across roles and settings. This research seeks to address that gap. Methods The Circle of Care Modeling (CCM) approach was used to build a model of medication communication activities across the circle of care. CCM positions the patient in the centre of his or her own healthcare system; providers and other roles are then modeled around the patient as a web of relationships. Recurrent medication communication activities were mapped to the medication management framework. The research occurred in three iterations, to test and revise the model: Iteration 1 consisted of a literature review and internal team discussion, Iteration 2 consisted of interviews, observation, and a discussion group at a Community Health Centre, and Iteration 3 consisted of interviews and a discussion group in the larger community. Results Each iteration provided further detail to the Circle of Care medication communication model. Specific medication communication activities were mapped along each communication pathway between roles and to the medication management framework. We could not map all medication communication activities to the medication management framework; we added Coordinate as a separate and distinct recurrent activity. We saw many examples of coordination activities, for instance, Medical Office Assistants acting as a liaison between pharmacists and family physicians to clarify prescription details. Conclusions Through the use of CCM we were able to unearth tacitly held knowledge to expand our understanding of medication communication. Drawing out the coordination activities could be a missing piece for us to better understand how to streamline and improve multi-step communication processes with a goal of improving patient safety. PMID:24134454
Integrase inhibitor reversal dynamics indicate unintegrated HIV-1 dna initiate de novo integration.
Thierry, Sylvain; Munir, Soundasse; Thierry, Eloïse; Subra, Frédéric; Leh, Hervé; Zamborlini, Alessia; Saenz, Dyana; Levy, David N; Lesbats, Paul; Saïb, Ali; Parissi, Vincent; Poeschla, Eric; Deprez, Eric; Delelis, Olivier
2015-03-12
Genomic integration, an obligate step in the HIV-1 replication cycle, is blocked by the integrase inhibitor raltegravir. A consequence is an excess of unintegrated viral DNA genomes, which undergo intramolecular ligation and accumulate as 2-LTR circles. These circularized genomes are also reliably observed in vivo in the absence of antiviral therapy and they persist in non-dividing cells. However, they have long been considered as dead-end products that are not precursors to integration and further viral propagation. Here, we show that raltegravir action is reversible and that unintegrated viral DNA is integrated in the host cell genome after raltegravir removal leading to HIV-1 replication. Using quantitative PCR approach, we analyzed the consequences of reversing prolonged raltegravir-induced integration blocks. We observed, after RAL removal, a decrease of 2-LTR circles and a transient increase of linear DNA that is subsequently integrated in the host cell genome and fuel new cycles of viral replication. Our data highly suggest that 2-LTR circles can be used as a reserve supply of genomes for proviral integration highlighting their potential role in the overall HIV-1 replication cycle.
NASA Astrophysics Data System (ADS)
Wang, Biao; Yu, Xiaofen; Li, Qinzhao; Zheng, Yu
2008-10-01
The paper aiming at the influence factor of round grating dividing error, rolling-wheel produce eccentricity and surface shape errors provides an amendment method based on rolling-wheel to get the composite error model which includes all influence factors above, and then corrects the non-circle measurement angle error of the rolling-wheel. We make soft simulation verification and have experiment; the result indicates that the composite error amendment method can improve the diameter measurement accuracy with rolling-wheel theory. It has wide application prospect for the measurement accuracy higher than 5 μm/m.
Siebolds, Marcus; Münzel, Brigitte; Müller, Roland; Häußermann, Sigrun; Paul, Mechthild; Kahl, Cornelia
2016-10-01
The integration of available early interventions and healthcare for families with children by practicing pediatricians has yet to be systematically established. For this reason, the Association of Statutory Health Insurance Physicians of Baden-Wuerttemberg established overarching, accredited, cross-system quality circles that serve to integrate all representatives of the healthcare system as well as child and youth welfare services. These quality circles are led by specially trained moderator tandems consisting of pediatricians and staff members from youth welfare services. The goal was to evaluate the endpoints of the regional implementation of cross-system quality circles for early interventions in the state of Baden-Wuerttemberg as well as the feasibility of establishing long-term training programs for cross-system moderator tandems. This was a noncontrolled, longitudinal study to prepare a yearly evaluation of the quality-circle assessments as well as to gather statistics on the training of the moderator tandems within the Association of Statutory Health Insurance Physicians of Baden-Wuerttemberg. A total of 59 moderator tandems were trained in nine separate training sessions within the project period from 2011 to 2015. Overall, 33 quality circles were founded. In 2015, 566 persons were participating in the respective circles. Over the course of the study between 26 and 33 of the 44 urban and rural districts in the state of Baden-Wuerttemberg had at least one quality circle dedicated to early interventions. Ten further circles are presently in the process of being founded; 29 moderators have yet to commence their activity or have withdrawn from the program. Between 59 and 81 % of the urban and rural districts implemented cross-system quality circles. The training of the moderator tandems proceeded without complications. Because of the dropout quota of the trained moderator tandems, systematic and continual training of new tandems proves to be necessary.
Rise, Sally, Rise: Communication through Dance.
ERIC Educational Resources Information Center
Bell, Davia
1999-01-01
Explores ring games--where participants form a circle, sing, dance, and take turns entering the circle--and how they can be used in the second-language classroom. The playful integration of vocalization and rhythmic body movement can have a powerful influence on speech fluency. (Author/VWL)
A five-step procedure for the clinical use of the MPD in neuropsychological assessment of children.
Wallbrown, F H; Fuller, G B
1984-01-01
Described a five-step procedure that can be used to detect organicity on the basis of children's performance on the Minnesota Percepto Diagnostic Test (MPD). The first step consists of examining the T score for rotations to determine whether it is below the cut-off score, which has been established empirically as an indicator of organicity. The second step consists of matching the examinee's configuration of error scores, separation of circle-diamond (SpCD), distortion of circle-diamond (DCD), and distortion of dots (DD), with empirically derived tables. The third step consists of considering the T score for rotations and error configuration jointly. The fourth step consists of using empirically established discriminant equations, and the fifth step involves using data from limits testing and other data sources. The clinical and empirical bases for the five-step procedure also are discussed.
Observations of 1E 1740.7-2942 with ROSAT and the VLA
NASA Technical Reports Server (NTRS)
Heindl, William A.; Prince, Thomas A.; Grunsfeld, John M.
1994-01-01
We have observed the Galactic black hole candidate 1E 1740.7-2942 in X-rays with both the ROSAT HRI and PSPC and at 1.5 and 4.9 GHz with the VLA. From the HRI observation we derive a position for 1E 1740.7-2942 of right ascension = 17 h 43 m 54.9 s, declination = -29 deg 44 min 45.3 sec (J2000), with a 90% confidence error circle of radius 8.5 min. Thermal bremsstrahlung fits to the PSPC data yield a column density of 1.12+1.51/-0.18 x 10(exp 23)/sq cm, consistent with earlier X-ray measurements. The VLA observation of 4.9 GHz revealed two sources. Source A, which is the core of a double aligned radio jet source (Mirabel et al. 1992), lies within the ROSAT error circle, further confirming its identification with 1E 1740.7-2942.
Binocular optical axis parallelism detection precision analysis based on Monte Carlo method
NASA Astrophysics Data System (ADS)
Ying, Jiaju; Liu, Bingqi
2018-02-01
According to the working principle of the binocular photoelectric instrument optical axis parallelism digital calibration instrument, and in view of all components of the instrument, the various factors affect the system precision is analyzed, and then precision analysis model is established. Based on the error distribution, Monte Carlo method is used to analyze the relationship between the comprehensive error and the change of the center coordinate of the circle target image. The method can further guide the error distribution, optimize control the factors which have greater influence on the comprehensive error, and improve the measurement accuracy of the optical axis parallelism digital calibration instrument.
A star recognition method based on the Adaptive Ant Colony algorithm for star sensors.
Quan, Wei; Fang, Jiancheng
2010-01-01
A new star recognition method based on the Adaptive Ant Colony (AAC) algorithm has been developed to increase the star recognition speed and success rate for star sensors. This method draws circles, with the center of each one being a bright star point and the radius being a special angular distance, and uses the parallel processing ability of the AAC algorithm to calculate the angular distance of any pair of star points in the circle. The angular distance of two star points in the circle is solved as the path of the AAC algorithm, and the path optimization feature of the AAC is employed to search for the optimal (shortest) path in the circle. This optimal path is used to recognize the stellar map and enhance the recognition success rate and speed. The experimental results show that when the position error is about 50″, the identification success rate of this method is 98% while the Delaunay identification method is only 94%. The identification time of this method is up to 50 ms.
Xu, Z N
2014-12-01
In this study, an error analysis is performed to study real water drop images and the corresponding numerically generated water drop profiles for three widely used static contact angle algorithms: the circle- and ellipse-fitting algorithms and the axisymmetric drop shape analysis-profile (ADSA-P) algorithm. The results demonstrate the accuracy of the numerically generated drop profiles based on the Laplace equation. A significant number of water drop profiles with different volumes, contact angles, and noise levels are generated, and the influences of the three factors on the accuracies of the three algorithms are systematically investigated. The results reveal that the above-mentioned three algorithms are complementary. In fact, the circle- and ellipse-fitting algorithms show low errors and are highly resistant to noise for water drops with small/medium volumes and contact angles, while for water drop with large volumes and contact angles just the ADSA-P algorithm can meet accuracy requirement. However, this algorithm introduces significant errors in the case of small volumes and contact angles because of its high sensitivity to noise. The critical water drop volumes of the circle- and ellipse-fitting algorithms corresponding to a certain contact angle error are obtained through a significant amount of computation. To improve the precision of the static contact angle measurement, a more accurate algorithm based on a combination of the three algorithms is proposed. Following a systematic investigation, the algorithm selection rule is described in detail, while maintaining the advantages of the three algorithms and overcoming their deficiencies. In general, static contact angles over the entire hydrophobicity range can be accurately evaluated using the proposed algorithm. The ease of erroneous judgment in static contact angle measurements is avoided. The proposed algorithm is validated by a static contact angle evaluation of real and numerically generated water drop images with different hydrophobicity values and volumes.
Analytic processing of distance.
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.
A pure DNA hydrogel with stable catalytic ability produced by one-step rolling circle amplification.
Huang, Yishun; Xu, Wanlin; Liu, Guoyuan; Tian, Leilei
2017-03-09
A rolling-circle-amplification method was developed to produce DNA hydrogels with horseradish-peroxidase-like catalytic capability. The catalytic hydrogel exhibits highly improved stability at elevated temperatures or during a long-term storage. Integrated with glucose oxidase, the complex hydrogel can be applied to the sensitive and reliable detection of glucose.
A Cost-Benefit Analysis of Hollow Water's Community Holistic Circle Healing Process.
ERIC Educational Resources Information Center
Couture, Joe; Parker, Ted; Couture, Ruth; Laboucane, Patti
Four Native American communities in Manitoba (Canada) known as Hollow Water devised a healing system for sexual abuse--the Hollow Water First Nation Community Holistic Circle Healing (CHCH). While integrating elements of a number of federal and provincially funded services, the 13-step CHCH healing process is based on the seven Midewin teachings…
ERIC Educational Resources Information Center
Klieger, Aviva; Ben-Hur, Yehuda; Bar-Yossef, Nurit
2010-01-01
The study examines the professional development of junior-high-school teachers participating in the Israeli "Katom" (Computer for Every Class, Student and Teacher) Program, begun in 2004. A three-circle support and training model was developed for teachers' professional development. The first circle applies to all teachers in the…
Grinding Method and Error Analysis of Eccentric Shaft Parts
NASA Astrophysics Data System (ADS)
Wang, Zhiming; Han, Qiushi; Li, Qiguang; Peng, Baoying; Li, Weihua
2017-12-01
RV reducer and various mechanical transmission parts are widely used in eccentric shaft parts, The demand of precision grinding technology for eccentric shaft parts now, In this paper, the model of X-C linkage relation of eccentric shaft grinding is studied; By inversion method, the contour curve of the wheel envelope is deduced, and the distance from the center of eccentric circle is constant. The simulation software of eccentric shaft grinding is developed, the correctness of the model is proved, the influence of the X-axis feed error, the C-axis feed error and the wheel radius error on the grinding process is analyzed, and the corresponding error calculation model is proposed. The simulation analysis is carried out to provide the basis for the contour error compensation.
Van Maele, Bénédicte; De Rijck, Jan; De Clercq, Erik; Debyser, Zeger
2003-01-01
Lentiviral vectors derived from human immunodeficiency virus type 1 (HIV-1) show great promise as gene carriers for future gene therapy. Insertion of a fragment containing the central polypurine tract (cPPT) in HIV-1 vector constructs is known to enhance transduction efficiency drastically, reportedly by facilitating the nuclear import of HIV-1 cDNA through a central DNA flap. We have studied the impact of the cPPT on the kinetics of HIV-1 vector transduction by real-time PCR. The kinetics of total HIV-1 DNA, two-long-terminal-repeat (2-LTR) circles, and, by an Alu-PCR, integrated proviral DNA were monitored. About 6 to 12 h after transduction, the total HIV-1 DNA reached a maximum level, followed by a steep decrease. The 2-LTR circles peaked after 24 to 48 h and were diluted upon cell division. Integration of HIV-1 DNA was first detected at 12 h postinfection. When HIV-1 vectors that contained the cPPT were used, DNA synthesis was similar but a threefold higher amount of 2-LTR circles was detected, confirming the impact on nuclear import. Moreover, a 10-fold increase in the amount of integrated DNA was observed in the presence of the cPPT. Only in the absence of the cPPT was a saturation in 2-LTR circle formation seen at a high multiplicity of infection, suggesting a role for the cPPT in overcoming a barrier to the nuclear import of HIV-1 DNA. A major effect of the central DNA flap on the juxtaposition of both LTRs is unlikely, since transduction with HIV-1 vectors containing ectopic cPPT fragments resulted in increased amounts of 2-LTR circles as well as integrated DNA. Inhibitors of transduction by cPPT-containing HIV vectors were also studied by real-time PCR. The reverse transcriptase inhibitor azidothymidine (AZT) and the nonnucleoside reverse transcriptase inhibitor α-APA clearly inhibited viral DNA synthesis, whereas integrase inhibitors such as the diketo acid L-708,906 and the pyranodipyrimidine V-165 specifically inhibited integration. PMID:12663775
An innovative integrated oxidation ditch with vertical circle (IODVC) for wastewater treatment.
Xia, Shi-bin; Liu, Jun-xin
2004-01-01
The oxidation ditch process is economic and efficient for wastewater treatment, but its application is limited in case where land is costly due to its large land area required. An innovative integrated oxidation ditch with vertical circle (IODVC) system was developed to treat domestic and industrial wastewater aiming to save land area. The new system consists of a single-channel divided into two ditches(the top one and the bottom one by a plate), a brush, and an innovative integral clarifier. Different from the horizontal circle of the conventional oxidation ditch, the flow of IODVC system recycles from the top zone to the bottom zone in the vertical circle as the brush is running, and then the IODVC saved land area required by about 50% compared with a conventional oxidation ditch with an intrachannel clarifier. The innovative integral clarifier is effective for separation of liquid and solids, and is preferably positioned at the opposite end of the brush in the ditch. It does not affect the hydrodynamic characteristics of the mixed liquor in the ditch, and the sludge can automatically return to the down ditch without any pump. In this study, experiments of domestic and dye wastewater treatment were carried out in bench scale and in full scale, respectively. Results clearly showed that the IODVC efficiently removed pollutants in the wastewaters, i.e., the average of COD removals for domestic and dye wastewater treatment were 95% and 90%, respectively, and that the IODVC process may provide a cost effective way for full scale dye wastewater treatment.
Dimensional synthesis of a 3-DOF parallel manipulator with full circle rotation
NASA Astrophysics Data System (ADS)
Ni, Yanbing; Wu, Nan; Zhong, Xueyong; Zhang, Biao
2015-07-01
Parallel robots are widely used in the academic and industrial fields. In spite of the numerous achievements in the design and dimensional synthesis of the low-mobility parallel robots, few research efforts are directed towards the asymmetric 3-DOF parallel robots whose end-effector can realize 2 translational and 1 rotational(2T1R) motion. In order to develop a manipulator with the capability of full circle rotation to enlarge the workspace, a new 2T1R parallel mechanism is proposed. The modeling approach and kinematic analysis of this proposed mechanism are investigated. Using the method of vector analysis, the inverse kinematic equations are established. This is followed by a vigorous proof that this mechanism attains an annular workspace through its circular rotation and 2 dimensional translations. Taking the first order perturbation of the kinematic equations, the error Jacobian matrix which represents the mapping relationship between the error sources of geometric parameters and the end-effector position errors is derived. With consideration of the constraint conditions of pressure angles and feasible workspace, the dimensional synthesis is conducted with a goal to minimize the global comprehensive performance index. The dimension parameters making the mechanism to have optimal error mapping and kinematic performance are obtained through the optimization algorithm. All these research achievements lay the foundation for the prototype building of such kind of parallel robots.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reister, D.B.; Unseren, M.A.
When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach tomore » the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.« less
Mathematical construction and perturbation analysis of Zernike discrete orthogonal points.
Shi, Zhenguang; Sui, Yongxin; Liu, Zhenyu; Peng, Ji; Yang, Huaijiang
2012-06-20
Zernike functions are orthogonal within the unit circle, but they are not over the discrete points such as CCD arrays or finite element grids. This will result in reconstruction errors for loss of orthogonality. By using roots of Legendre polynomials, a set of points within the unit circle can be constructed so that Zernike functions over the set are discretely orthogonal. Besides that, the location tolerances of the points are studied by perturbation analysis, and the requirements of the positioning precision are not very strict. Computer simulations show that this approach provides a very accurate wavefront reconstruction with the proposed sampling set.
Implementation and simulations of the sphere solution in FAST
NASA Astrophysics Data System (ADS)
Murgolo, F. P.; Schirone, M. G.; Lattanzi, M.; Bernacca, P. L.
1989-06-01
The details of the implementation of the sphere solution software in the Fundamental Astronomy by Space Techniques (FAST) consortium, are described. The simulation results for realistic data sets, both with and without grid-step errors are given. Expected errors on the astrometric parameters of the primary stars and the precision of the reference great circle zero points, are provided as a function of mission duration. The design matrix, the diagrams of the context processor and the processors experimental results are given.
["Second victim" - error, crises and how to get out of it].
von Laue, N; Schwappach, D; Hochreutener, M
2012-06-01
Medical errors do not only harm patients ("first victims"). Almost all health care professionals become a so-called "second victim" once in their career by being involved in a medical error. Studies show that error involvement can have a tremendous impact on health care workers leading to burnout, depression and professional crisis. Moreover persons involved in errors show a decline in job performance and jeopardize therefore patient safety. Blaming the person is one of the typical psychological reactions after an error happened as the attribution theory tells. The self-esteem gets stabilized if we can put blame on someone and pick out a scapegoat. But standing alone makes the emotional situation even worse. A vicious circle can evolve with tragic effect for the individual and negative implications for patient safety and the health care setting.
Linking Science Analysis with Observation Planning: A Full Circle Data Lifecycle
NASA Technical Reports Server (NTRS)
Grosvenor, Sandy; Jones, Jeremy; Koratkar, Anuradha; Li, Connie; Mackey, Jennifer; Neher, Ken; Wolf, Karl; Obenschain, Arthur F. (Technical Monitor)
2001-01-01
A clear goal of the Virtual Observatory (VO) is to enable new science through analysis of integrated astronomical archives. An additional and powerful possibility of the VO is to link and integrate these new analyses with planning of new observations. By providing tools that can be used for observation planning in the VO, the VO will allow the data lifecycle to come full circle: from theory to observations to data and back around to new theories and new observations. The Scientist's Expert Assistant (SEA) Simulation Facility (SSF) is working to combine the ability to access existing archives with the ability to model and visualize new observations. Integrating the two will allow astronomers to better use the integrated archives of the VO to plan and predict the success of potential new observations more efficiently, The full circle lifecycle enabled by SEA can allow astronomers to make substantial leaps in the quality of data and science returns on new observations. Our paper examines the exciting potential of integrating archival analysis with new observation planning, such as performing data calibration analysis on archival images and using that analysis to predict the success of new observations, or performing dynamic signal-to-noise analysis combining historical results with modeling of new instruments or targets. We will also describe how the development of the SSF is progressing and what have been its successes and challenges.
Linking Science Analysis with Observation Planning: A Full Circle Data Lifecycle
NASA Technical Reports Server (NTRS)
Jones, Jeremy; Grosvenor, Sandy; Wolf, Karl; Li, Connie; Koratkar, Anuradha; Powers, Edward I. (Technical Monitor)
2001-01-01
A clear goal of the Virtual Observatory (VO) is to enable new science through analysis of integrated astronomical archives. An additional and powerful possibility of the VO is to link and integrate these new analyses with planning of new observations. By providing tools that can be used for observation planning in the VO, the VO will allow the data lifecycle to come full circle: from theory to observations to data and back around to new theories and new observations. The Scientist's Expert Assistant (SEA) Simulation Facility (SSF) is working to combine the ability to access existing archives with the ability to model and visualize new observations. Integrating the two will allow astronomers to better use the integrated archives of the VO to plan and predict the success of potential new observations. The full circle lifecycle enabled by SEA can allow astronomers to make substantial leaps in the quality of data and science returns on new observations. Our paper will examine the exciting potential of integrating archival analysis with new observation planning, such as performing data calibration analysis on archival images and using that analysis to predict the success of new observations, or performing dynamic signal-to-noise analysis combining historical results with modeling of new instruments or targets. We will also describe how the development of the SSF is progressing and what has been its successes and challenges.
The Anne Frank Haven: A case of an alternative educational program in an integrative Kibbutz setting
NASA Astrophysics Data System (ADS)
Ben-Peretz, Miriam; Giladi, Moshe; Dror, Yuval
1992-01-01
The essential features of the programme of the Anne Frank Haven are the complete integration of children from low SES and different cultural backgrounds with Kibbutz children; a holistic approach to education; and the involvement of the whole community in an "open" residential school. After 33 years, it is argued that the experiment has proved successful in absorbing city-born youth in the Kibbutz, enabling at-risk populations to reach significant academic achievements, and ensuring their continued participation in the dominant culture. The basic integration model consists of "layers" of concentric circles, in dynamic interaction. The innermost circle is the class, the learning community. The Kibbutz community and the foster parents form a supportive, enveloping circle, which enables students to become part of the outer community and to intervene in it. A kind of meta-environment, the inter-Kibbutz partnership and the Israeli educational system, influence the program through decision making and guidance. Some of the principles of the Haven — integration, community involvement, a year's induction for all new students, and open residential settings — could be useful for cultures and societies outside the Kibbutz. The real "secret" of success of an alternative educational program is the dedicated, motivated and highly trained staff.
Integrated Marketing Communications
ERIC Educational Resources Information Center
Black, Jim
2004-01-01
Integration has become a cliche in enrollment management and student services circles. The term is used to describe everything from integrated marketing to seamless services. Often, it defines organizational structures, processes, student information systems, and even communities. In Robert Sevier's article in this issue of "College and…
Implementing Collaborative Learning Methods in the Political Science Classroom
ERIC Educational Resources Information Center
Wolfe, Angela
2012-01-01
Collaborative learning is one, among other, active learning methods, widely acclaimed in higher education. Consequently, instructors in fields that lack pedagogical training often implement new learning methods such as collaborative learning on the basis of trial and error. Moreover, even though the benefits in academic circles are broadly touted,…
An ultra-accurate numerical method in the design of liquid phononic crystals with hard inclusion
NASA Astrophysics Data System (ADS)
Li, Eric; He, Z. C.; Wang, G.; Liu, G. R.
2017-12-01
The phononics crystals (PCs) are periodic man-made composite materials. In this paper, a mass-redistributed finite element method (MR-FEM) is formulated to study the wave propagation within liquid PCs with hard inclusion. With a perfect balance between stiffness and mass in the MR-FEM model, the dispersion error of longitudinal wave is minimized by redistribution of mass. Such tuning can be easily achieved by adjusting the parameter r that controls the location of integration points of mass matrix. More importantly, the property of mass conservation in the MR-FEM model indicates that the locations of integration points inside or outside the element are immaterial. Four numerical examples are studied in this work, including liquid PCs with cross and circle hard inclusions, different size of inclusion and defect. Compared with standard finite element method, the numerical results have verified the accuracy and effectiveness of MR-FEM. The proposed MR-FEM is a unique and innovative numerical approach with its outstanding features, which has strong potentials to study the stress wave within multi-physics PCs.
Trajectory Control of Rendezvous with Maneuver Target Spacecraft
NASA Technical Reports Server (NTRS)
Zhou, Zhinqiang
2012-01-01
In this paper, a nonlinear trajectory control algorithm of rendezvous with maneuvering target spacecraft is presented. The disturbance forces on the chaser and target spacecraft and the thrust forces on the chaser spacecraft are considered in the analysis. The control algorithm developed in this paper uses the relative distance and relative velocity between the target and chaser spacecraft as the inputs. A general formula of reference relative trajectory of the chaser spacecraft to the target spacecraft is developed and applied to four different proximity maneuvers, which are in-track circling, cross-track circling, in-track spiral rendezvous and cross-track spiral rendezvous. The closed-loop differential equations of the proximity relative motion with the control algorithm are derived. It is proven in the paper that the tracking errors between the commanded relative trajectory and the actual relative trajectory are bounded within a constant region determined by the control gains. The prediction of the tracking errors is obtained. Design examples are provided to show the implementation of the control algorithm. The simulation results show that the actual relative trajectory tracks the commanded relative trajectory tightly. The predicted tracking errors match those calculated in the simulation results. The control algorithm developed in this paper can also be applied to interception of maneuver target spacecraft and relative trajectory control of spacecraft formation flying.
Position and force control of a vehicle with two or more steerable drive wheels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reister, D.B.; Unseren, M.A.
1992-10-01
When a vehicle with two or more steerable drive wheels is traveling in a circle, the motion of the wheels is constrained. The wheel translational velocity divided by the radius to the center of rotation must be the same for all wheels. When the drive wheels are controlled independently using position control, the motion of the wheels may violate the constraints and the wheels may slip. Consequently, substantial errors can occur in the orientation of the vehicle. A vehicle with N drive wheels has (N - 1) constraints and one degree of freedom. We have developed a new approach tomore » the control of a vehicle with N steerable drive wheels. The novel aspect of our approach is the use of force control. To control the vehicle, we have one degree of freedom for the position on the circle and (N - 1) forces that can be used to reduce errors. Recently, Kankaanranta and Koivo developed a control architecture that allows the force and position degrees of freedom to be decoupled. In the work of Kankaanranta and Koivo the force is an exogenous input. We have made the force endogenous by defining the force in terms of the errors in satisfying the rigid body kinematic constraints. We have applied the control architecture to the HERMIES-III robot and have measured a dramatic reduction in error (more than a factor of 20) compared to motions without force control.« less
The Nature of Infinity in Quantum Field Calculations
NASA Astrophysics Data System (ADS)
Kriske, Richard
2011-05-01
In many textbooks on Quantum Field Theory it has been noted that an infinity is taken a circle and the flux is calculated from the A field in that manner. There are of course many such examples of this sort of calculation using infinity as a circle. This author would like to point out that if the three dimensions of space are curved and the one dimension of time is not, in say a four space, infinity is the horizon, which is not a circle but rather a sphere; as long as space-time is curved uniformly, smoothly and has positive curvature. This author believes the math may be in error, since maps of the CMBR seem to indicate a ``Swiss-Cheese'' type of topology, wherein the Sphere at infinity (the Horizon of the Universe), has holes in it that can readily be seen. This author believes that these irregularities most certainly have a calculable effect on QED, QCD and Quantum Field Theory.
Object-based attention benefits reveal selective abnormalities of visual integration in autism.
Falter, Christine M; Grant, Kate C Plaisted; Davis, Greg
2010-06-01
A pervasive integration deficit could provide a powerful and elegant account of cognitive processing in autism spectrum disorders (ASD). However, in the case of visual Gestalt grouping, typically assessed by tasks that require participants explicitly to introspect on their own grouping perception, clear evidence for such a deficit remains elusive. To resolve this issue, we adopt an index of Gestalt grouping from the object-based attention literature that does not require participants to assess their own grouping perception. Children with ASD and mental- and chronological-age matched typically developing children (TD) performed speeded orientation discriminations of two diagonal lines. The lines were superimposed on circles that were either grouped together or segmented on the basis of color, proximity or these two dimensions in competition. The magnitude of performance benefits evident for grouped circles, relative to ungrouped circles, provided an index of grouping under various conditions. Children with ASD showed comparable grouping by proximity to the TD group, but reduced grouping by similarity. ASD seems characterized by a selective bias away from grouping by similarity combined with typical levels of grouping by proximity, rather than by a pervasive integration deficit.
Integration of length and curvature in haptic perception.
Panday, Virjanand; Tiest, Wouter M Bergmann; Kappers, Astrid M L
2014-01-24
We investigated if and how length and curvature information are integrated when an object is explored in one hand. Subjects were asked to explore four types of objects between thumb and index finger. Objects differed in either length, curvature, both length and curvature correlated as in a circle, or anti-correlated. We found that when both length and curvature are present, performance is significantly better than when only one of the two cues is available. Therefore, we conclude that there is integration of length and curvature. Moreover, if the two cues are correlated in a circular cross-section instead of in an anti-correlated way, performance is better than predicted by a combination of two independent cues. We conclude that integration of curvature and length is highly efficient when the cues in the object are combined as in a circle, which is the most common combination of curvature and length in daily life.
The dynamics of SIV 2-LTR Circles in the Presence and Absence of CD8 + Cells
Policicchio, Benjamin B.; Cardozo, Erwing Fabian; Sette, Paola; ...
2018-04-11
CD8 +cells play a key role in HIV/SIV infection, but their specific mechanism(s) of action in controlling the virus are unclear. 2-LTR circles are extrachromosomal products generated upon failed integration of HIV/SIV. To understand the specific effects of CD8 +cells on infected cells, we analyzed the dynamics of 2-LTR circles in SIVmac251-infected rhesus macaques (RM) treated with an integrase inhibitor (INT). Twenty RMs underwent CD8 +cell depletion, received RAL monotherapy or a combination of both. Blood, lymph nodes (LNs) and gut biopsies were routinely sampled. Plasma viral loads (pVLs) and 2-LTR circles from PBMCs and LN lymphocytes were measured withmore » qRT-PCR. In the CD8 depletion group, an ~1 log increase in pVLs and a slow increase in PBMC 2-LTRs occurred following depletion. In the INT group, a strong decline in pVLs upon treatment initiation and no change in 2-LTR levels were observed. In the INT and CD8 +cell depletion group, a similar increase in pVLs following CD8 depletion was observed, with a modest decline following INT initiation, and 2-LTR circles significantly increased in PBMCs and LNs. Analyzing the 2-LTR data across all treatment groups with a mathematical model indicates that the data best supports an effect of CD8 +cells in killing cells prior to viral integration. Sensitivity analyses of these results confirm that effect, but also allow for additional effects, which the data does not discriminate well. Overall, we show that INT does not significantly increase the levels of 2-LTR circles. However, CD8 +cell depletion increases the 2-LTR levels, which are enhanced in the presence of an INT. CD8 +T cells play an essential role in controlling HIV and simian immunodeficiency virus (SIV) infection, but the specific mechanisms involved remain poorly understood. Due to failed viral infection, HIV and SIV can form 2-LTR extrachromosomal circles that can be quantified. We present novel data on the dynamics of these 2-LTR forms in a SIV-infected macaque model under three different treatment conditions: depletion of CD8 +cells; administration of the integrase inhibitor in a monotherapy, which favors the formation of 2-LTR circles; and combination of the two treatments. We used a new mathematical model to help interpret the data, and the results suggest that CD8 +cells exert a killing effect on infected cells prior to virus integration. These results provide new insights into the mechanisms of action of CD8 +cells in SIV infection. Here, confirmation of our results would be an important step in understanding immune control of HIV.« less
The dynamics of SIV 2-LTR Circles in the Presence and Absence of CD8 + Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Policicchio, Benjamin B.; Cardozo, Erwing Fabian; Sette, Paola
CD8 +cells play a key role in HIV/SIV infection, but their specific mechanism(s) of action in controlling the virus are unclear. 2-LTR circles are extrachromosomal products generated upon failed integration of HIV/SIV. To understand the specific effects of CD8 +cells on infected cells, we analyzed the dynamics of 2-LTR circles in SIVmac251-infected rhesus macaques (RM) treated with an integrase inhibitor (INT). Twenty RMs underwent CD8 +cell depletion, received RAL monotherapy or a combination of both. Blood, lymph nodes (LNs) and gut biopsies were routinely sampled. Plasma viral loads (pVLs) and 2-LTR circles from PBMCs and LN lymphocytes were measured withmore » qRT-PCR. In the CD8 depletion group, an ~1 log increase in pVLs and a slow increase in PBMC 2-LTRs occurred following depletion. In the INT group, a strong decline in pVLs upon treatment initiation and no change in 2-LTR levels were observed. In the INT and CD8 +cell depletion group, a similar increase in pVLs following CD8 depletion was observed, with a modest decline following INT initiation, and 2-LTR circles significantly increased in PBMCs and LNs. Analyzing the 2-LTR data across all treatment groups with a mathematical model indicates that the data best supports an effect of CD8 +cells in killing cells prior to viral integration. Sensitivity analyses of these results confirm that effect, but also allow for additional effects, which the data does not discriminate well. Overall, we show that INT does not significantly increase the levels of 2-LTR circles. However, CD8 +cell depletion increases the 2-LTR levels, which are enhanced in the presence of an INT. CD8 +T cells play an essential role in controlling HIV and simian immunodeficiency virus (SIV) infection, but the specific mechanisms involved remain poorly understood. Due to failed viral infection, HIV and SIV can form 2-LTR extrachromosomal circles that can be quantified. We present novel data on the dynamics of these 2-LTR forms in a SIV-infected macaque model under three different treatment conditions: depletion of CD8 +cells; administration of the integrase inhibitor in a monotherapy, which favors the formation of 2-LTR circles; and combination of the two treatments. We used a new mathematical model to help interpret the data, and the results suggest that CD8 +cells exert a killing effect on infected cells prior to virus integration. These results provide new insights into the mechanisms of action of CD8 +cells in SIV infection. Here, confirmation of our results would be an important step in understanding immune control of HIV.« less
Hill, A. B.; Szostek, A.; Corbel, S.; ...
2011-07-08
We present an analysis of high energy (HE; 0.1–300 GeV) γ-ray observations of 1FGL J1227.9–4852 with the Fermi Gamma-ray Space Telescope, follow-up radio observations with the Australia Telescope Compact Array, Giant Metrewave Radio Telescope and Parkes radio telescopes of the same field and follow-up optical observations with the ESO VLT. We also examine archival XMM– Newton and INTEGRAL X-ray observations of the region around this source. The γ-ray spectrum of 1FGL J1227.9–4852 is best fitted with an exponentially cut-off power law, reminiscent of the population of pulsars observed by Fermi. A previously unknown, compact radio source within the 99.7 permore » cent error circle of 1FGL J1227.9–4852 is discovered and has a morphology consistent either with an AGN core/jet structure or with two roughly symmetric lobes of a distant radio galaxy. A single bright X-ray source XSS J12270–4859, a low-mass X-ray binary, also lies within the 1FGL J1227.9–4852 error circle and we report the first detection of radio emission from this source. The potential association of 1FGL J1227.9–4852 with each of these counterparts is discussed. Based upon the available data we find the association of the γ-ray source to the compact double radio source unlikely and suggest that XSS J12270–4859 is a more likely counterpart to the new HE source. As a result, we propose that XSS J12270–4859 may be a millisecond binary pulsar and draw comparisons with PSR J1023+0038.« less
Verification of real sensor motion for a high-dynamic 3D measurement inspection system
NASA Astrophysics Data System (ADS)
Breitbarth, Andreas; Correns, Martin; Zimmermann, Manuel; Zhang, Chen; Rosenberger, Maik; Schambach, Jörg; Notni, Gunther
2017-06-01
Inline three-dimensional measurements are a growing part of optical inspection. Considering increasing production capacities and economic aspects, dynamic measurements under motion are inescapable. Using a sequence of different pattern, like it is generally done in fringe projection systems, relative movements of the measurement object with respect to the 3d sensor between the images of one pattern sequence have to be compensated. Based on the application of fully automated optical inspection of circuit boards at an assembly line, the knowledge of the relative speed of movement between the measurement object and the 3d sensor system should be used inside the algorithms of motion compensation. Optimally, this relative speed is constant over the whole measurement process and consists of only one motion direction to avoid sensor vibrations. The quantified evaluation of this two assumptions and the error impact on the 3d accuracy are content of the research project described by this paper. For our experiments we use a glass etalon with non-transparent circles and transmitted light. Focused on the circle borders, this is one of the most reliable methods to determine subpixel positions using a couple of searching rays. The intersection point of all rays characterize the center of each circle. Based on these circle centers determined with a precision of approximately 1=50 pixel, the motion vector between two images could be calculated and compared with the input motion vector. Overall, the results are used to optimize the weight distribution of the 3d sensor head and reduce non-uniformly vibrations. Finally, there exists a dynamic 3d measurement system with an error of motion vectors about 4 micrometer. Based on this outcome, simulations result in a 3d standard deviation at planar object regions of 6 micrometers. The same system yields a 3d standard deviation of 9 µm without the optimization of weight distribution.
Path integration: effect of curved path complexity and sensory system on blindfolded walking.
Koutakis, Panagiotis; Mukherjee, Mukul; Vallabhajosula, Srikant; Blanke, Daniel J; Stergiou, Nicholas
2013-02-01
Path integration refers to the ability to integrate continuous information of the direction and distance traveled by the system relative to the origin. Previous studies have investigated path integration through blindfolded walking along simple paths such as straight line and triangles. However, limited knowledge exists regarding the role of path complexity in path integration. Moreover, little is known about how information from different sensory input systems (like vision and proprioception) contributes to accurate path integration. The purpose of the current study was to investigate how sensory information and curved path complexity affect path integration. Forty blindfolded participants had to accurately reproduce a curved path and return to the origin. They were divided into four groups that differed in the curved path, circle (simple) or figure-eight (complex), and received either visual (previously seen) or proprioceptive (previously guided) information about the path before they reproduced it. The dependent variables used were average trajectory error, walking speed, and distance traveled. The results indicated that (a) both groups that walked on a circular path and both groups that received visual information produced greater accuracy in reproducing the path. Moreover, the performance of the group that received proprioceptive information and later walked on a figure-eight path was less accurate than their corresponding circular group. The groups that had the visual information also walked faster compared to the group that had proprioceptive information. Results of the current study highlight the roles of different sensory inputs while performing blindfolded walking for path integration. Copyright © 2012 Elsevier B.V. All rights reserved.
An Integrative Risk Management/Governance Framework for Homeland Security Decision Making
2008-03-01
key modes of transportation include highways, motor carrier (trucking), motor coach ( intercity bus), maritime, pipeline, rail (passenger and freight...2004 Overview: A blast tore apart a metro train car in Moscow during the morning rush hour on February 6, 2004. The train was traveling between the...Circle Line train, No. 204, traveling from Liverpool Street to Aldgate Station. Within one minute, a second explosion took place on Circle Line train
Integrating Mathematics and Science: Ecology and Venn Diagrams
ERIC Educational Resources Information Center
Leszczynski, Eliza; Munakata, Mika; Evans, Jessica M.; Pizzigoni, Francesca
2014-01-01
Efforts to integrate mathematics and science have been widely recognized by mathematics and science educators. However, successful integration of these two important school disciplines remains a challenge. In this article, a mathematics and science activity extends the use of Venn diagrams to a life science context and then circles back to a…
Eccentricity error identification and compensation for high-accuracy 3D optical measurement
He, Dong; Liu, Xiaoli; Peng, Xiang; Ding, Yabin; Gao, Bruce Z
2016-01-01
The circular target has been widely used in various three-dimensional optical measurements, such as camera calibration, photogrammetry and structured light projection measurement system. The identification and compensation of the circular target systematic eccentricity error caused by perspective projection is an important issue for ensuring accurate measurement. This paper introduces a novel approach for identifying and correcting the eccentricity error with the help of a concentric circles target. Compared with previous eccentricity error correction methods, our approach does not require taking care of the geometric parameters of the measurement system regarding target and camera. Therefore, the proposed approach is very flexible in practical applications, and in particular, it is also applicable in the case of only one image with a single target available. The experimental results are presented to prove the efficiency and stability of the proposed approach for eccentricity error compensation. PMID:26900265
Eccentricity error identification and compensation for high-accuracy 3D optical measurement.
He, Dong; Liu, Xiaoli; Peng, Xiang; Ding, Yabin; Gao, Bruce Z
2013-07-01
The circular target has been widely used in various three-dimensional optical measurements, such as camera calibration, photogrammetry and structured light projection measurement system. The identification and compensation of the circular target systematic eccentricity error caused by perspective projection is an important issue for ensuring accurate measurement. This paper introduces a novel approach for identifying and correcting the eccentricity error with the help of a concentric circles target. Compared with previous eccentricity error correction methods, our approach does not require taking care of the geometric parameters of the measurement system regarding target and camera. Therefore, the proposed approach is very flexible in practical applications, and in particular, it is also applicable in the case of only one image with a single target available. The experimental results are presented to prove the efficiency and stability of the proposed approach for eccentricity error compensation.
Zhou, Houshi; Sun, Jian; Ji, Xiaotan; Lin, Jing; Tang, Shujin; Zeng, Jinsheng; Fan, Yu-hua
2016-01-01
Abstract The quality of collateral circulation affects the severity and prognosis of stroke patients. The effect of the circle of Willis, which is the primary collateral circulation, on ischemic stroke has attracted significant attention. This study was designed to investigate the effect of different circles of Willis types on stroke severity and prognosis in patients with noncardiac stroke. A total of 376 patients with noncardiac ischemic stroke, who were treated by the specialty team of cerebrovascular diseases at the First Affiliated Hospital of Sun Yat-sen Hospital, were successively enrolled in this study. The detailed clinical characteristics of the patients were recorded upon admission, including risk factors of vascular disease and National Institutes of Health Stroke Scale (NIHSS) scores. The patients were divided into groups of different circles of Willis types based on magnetic resonance angiography (MRA) that was performed within 3 days of admission—type I: complete circle of Willis; type II: complete anterior half of the circle of Willis and incomplete posterior half of the circle of Willis; type III: incomplete anterior half of the circle of Willis and complete posterior half of the circle of Willis; and type IV: incomplete anterior and posterior halves of the circle of Willis. Patients were re-evaluated for NIHSS scores at discharge and after discharge. The modified Rankin score (mRS) was recorded for 90 days, and stroke recurrence and death after 90 days were also recorded until the end of the study. The 376 patients were divided into 4 groups based on the MRA—type I group: 92 patients (24.5%); type II group: 215 patients (57.2%); type III group: 12 patients (3.2%), and type IV group: 57 patients (15.2%). NIHSS scores at admission and discharge were significantly lower for the type I group compared with those for the type II and type IV groups (P < 0.05). NIHSS scores were higher in the groups with an incomplete circle of Willis compared with the group with a complete circle of Willis. A poor recovery rate was highest for the type IV group, whereas a good recovery rate was highest for the type I group. The logistic regression analysis showed that a complete circle of Willis was one of the predictors of suitable recovery (odds ratio [OR] = 0.708, 95% confidence interval [CI]: 0.554–0.906). Circle of Willis type was associated with stroke severity and patient prognosis, whereas an incomplete circle of Willis was associated with more severe conditions and a higher 90-day poor diagnosis rate. A complete circle of Willis was an independent predictor of good prognosis. PMID:26962785
Yang, L M; Shu, C; Wang, Y
2016-03-01
In this work, a discrete gas-kinetic scheme (DGKS) is presented for simulation of two-dimensional viscous incompressible and compressible flows. This scheme is developed from the circular function-based GKS, which was recently proposed by Shu and his co-workers [L. M. Yang, C. Shu, and J. Wu, J. Comput. Phys. 274, 611 (2014)]. For the circular function-based GKS, the integrals for conservation forms of moments in the infinity domain for the Maxwellian function-based GKS are simplified to those integrals along the circle. As a result, the explicit formulations of conservative variables and fluxes are derived. However, these explicit formulations of circular function-based GKS for viscous flows are still complicated, which may not be easy for the application by new users. By using certain discrete points to represent the circle in the phase velocity space, the complicated formulations can be replaced by a simple solution process. The basic requirement is that the conservation forms of moments for the circular function-based GKS can be accurately satisfied by weighted summation of distribution functions at discrete points. In this work, it is shown that integral quadrature by four discrete points on the circle, which forms the D2Q4 discrete velocity model, can exactly match the integrals. Numerical results showed that the present scheme can provide accurate numerical results for incompressible and compressible viscous flows with roughly the same computational cost as that needed by the Roe scheme.
ERRATUM: 'MAPPING THE GAS TURBULENCE IN THE COMA CLUSTER: PREDICTIONS FOR ASTRO-H'
NASA Technical Reports Server (NTRS)
Zuhone, J. A.; Markevitch, M.; Zhuravleva, I.
2016-01-01
The published version of this paper contained an error in Figure 5. This figure is intended to show the effect on the structure function of subtracting the bias induced by the statistical and systematic errors on the line shift. The filled circles show the bias-subtracted structure function. The positions of these points in the left panel of the original figure were calculated incorrectly. The figure is reproduced below (with the original caption) with the correct values for the bias-subtracted structure function. No other computations or figures in the original manuscript are affected.
Wangt, Dan-Chen; Hu, Li-Hui; Zhou, Yu-Hui; Huang, Yu-Ting; Li, Xinhua; Zhu, Jun-Jie
2014-04-01
An isothermal, highly sensitive and specific assay for the detection of hsa-miR-21 with the integration of QDs tagging and rolling circle amplification was offered. In addition, a dual channel strategy for miRNA detection was proposed: anodic stripping voltammetry (ASV) and fluorescent method were both performed for the final Cd2+ signal readout. The designed strategy exhibited good specificity to hsa-miR-21 and presented comparable detection results by detection methods.
Finite-volume spectra of the Lee-Yang model
NASA Astrophysics Data System (ADS)
Bajnok, Zoltan; el Deeb, Omar; Pearce, Paul A.
2015-04-01
We consider the non-unitary Lee-Yang minimal model in three different finite geometries: (i) on the interval with integrable boundary conditions labelled by the Kac labels ( r, s) = (1 , 1) , (1 , 2), (ii) on the circle with periodic boundary conditions and (iii) on the periodic circle including an integrable purely transmitting defect. We apply φ 1,3 integrable perturbations on the boundary and on the defect and describe the flow of the spectrum. Adding a Φ1,3 integrable perturbation to move off-criticality in the bulk, we determine the finite size spectrum of the massive scattering theory in the three geometries via Thermodynamic Bethe Ansatz (TBA) equations. We derive these integral equations for all excitations by solving, in the continuum scaling limit, the TBA functional equations satisfied by the transfer matrices of the associated A 4 RSOS lattice model of Forrester and Baxter in Regime III. The excitations are classified in terms of ( m, n) systems. The excited state TBA equations agree with the previously conjectured equations in the boundary and periodic cases. In the defect case, new TBA equations confirm previously conjectured transmission factors.
VizieR Online Data Catalog: W1J00 and W2J00 Transit Circle Catalogs (Rafferty+, 2016)
NASA Astrophysics Data System (ADS)
Rafferty, T. J.; Holdenried, E. R.; Urban, S. E.
2016-06-01
The W1J00, named because it was the first (of two) Washington transit circle catalog to be referred to the Equinox of J2000.0, is the result of observations made with the Six-inch Transit Circle in Washington, D.C., between September 1977 and July 1982. The observing program was structured to be absolute, in the sense that the positions were not explicitly relying on any previous observations. The absolute positions were defined with respect to an internally consistent frame that was unique to the particular instrument. Following the reductions, comparisons with stars from the Hipparcos Catalogue (European Space Agency 1997) revealed unaccounted for systematic differences on the level of 100-200mas. It was decided, therefore, to include data on both the absolute positions reduced in way common to many past Washington transit circle catalogs, as well as the positions differentially adjusted to the system of the Hipparcos Catalog. The W1J00 contains mean positions of 7267 stars and 4383 observations of solar system objects. The majority of the stars fall into two categories; those from the Fifth Fundamental Catalog (FK5; Fricke et al 1988), and those from the Catalog Of 3539 Zodiacal Stars For The Equinox 1950.0 (Robertson 1940). The solar system objects include the Sun, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, eight minor planets (Eunomia, Flora, Hebe, Iris, Juno, Metis, Pallas, and Vesta), and the dwarf planet Ceres. Characteristics of the W1J00 catalog: Category Range Average ------------------------------------------------------------- Magnitudes -1.6 to 10.4 7.18 RA standard errors of the mean 15 to 460 mas 98 mas Dec standard errors of the mean 10 to 400 mas 107 mas RA Number of observations / star 3 to 187 10 Dec Number of observations / star 2 to 179 10 Declination coverage -39 to +90 degrees ------------------------------------------------------------- Details of the W1J00 can be found in Rafferty, Holdenried, and Urban (2016, Publ. USNO, 2nd series, vol. XXVII (part 1)). The W2J00 is the result of observations made with the Six-inch Transit Circle in Washington, D.C., and the Seven-inch Transit Circle at the Black Birch station near Blenheim, New Zealand. It is named as such because it was the second (of two) transit circle catalogs to be referred to the Equinox of J2000.0, and reduced at the Washington D.C. headquarters of the U.S. Naval Observatory. It is sometimes referred to as the "Pole-to-Pole" program due to the fact that the telescopes were situated at latitudes such that a fundamental determination could be made of the azimuth using circumpolar stars of both the northern and southern sky. The observations were made between April 1985 and February 1996. The W2J00 project is the latest and largest of a long series of transit circle catalogs produced by the U.S. Naval Observatory. It is also, because of advancing technologies, certainly the last. The observing program was structured to be absolute, in the sense that the reported positions were not to explicitly rely on previous observations. However, with the availability of Hipparcos observational data, it was decided to differentially adjust the observations to the ICRF using the Hipparcos star positions (ESA, 1997, Cat. I/239). A catalog on the ICRF was judged be more useful than one tied to the dynamical reference frame, as was the tradition. The W2J00 contains mean positions of 44,395 globally distributed stars, 5048 observations of the planets, and 6518 observations of the brighter minor planets. The majority of stars are FK stars (Fricke, et al., 1988, Cat. I/149 and 1991, Cat. I/175) and International Reference Stars (IRS) (Corbin, 1991, Cat. I/172). The solar system objects include Mars, Jupiter, Saturn, Uranus, Neptune, twelve minor planets (Amphitrite, Eunomia, Flora, Hebe, Hygiea, Iris, Juno, Melphomene, Metis, Nemausa, Pallas, and Vesta), and the dwarf planet Ceres. Daytime observations of the Sun, Mercury, Venus, Mars, and bright stars were made but not included in the final catalog due to the problems inherent in reducing observations made in the daylight. The W2J00 observing program used both the Six-inch Transit Circle and Seven-inch Transit Circle. Final positions are a combination of observations from both telescopes (for those stars in common). The authors have decided to present not only the combined positions, but the individual telescope's positions should future researchers decide to investigate the data based on which instrument was used. Characteristics of the W2J00 catalog: Category Range Average ------------------------------------------------------------- Magnitudes -1.6 to 9.91 6.84 RA standard errors of the mean 3 to 441 mas 68 mas Dec standard errors of the mean 1 to 448 mas 76 mas RA Number of observations / star 3 to 411 14 Dec Number of observations / star 2 to 418 14 Declination coverage -90 to +90 degrees ------------------------------------------------------------- Details of the W2J00 can be found in Holdenried and Rafferty (2016, PUSNO, 2nd series, vol. XXVII (part 2)). (4 data files).
Procedural error monitoring and smart checklists
NASA Technical Reports Server (NTRS)
Palmer, Everett
1990-01-01
Human beings make and usually detect errors routinely. The same mental processes that allow humans to cope with novel problems can also lead to error. Bill Rouse has argued that errors are not inherently bad but their consequences may be. He proposes the development of error-tolerant systems that detect errors and take steps to prevent the consequences of the error from occurring. Research should be done on self and automatic detection of random and unanticipated errors. For self detection, displays should be developed that make the consequences of errors immediately apparent. For example, electronic map displays graphically show the consequences of horizontal flight plan entry errors. Vertical profile displays should be developed to make apparent vertical flight planning errors. Other concepts such as energy circles could also help the crew detect gross flight planning errors. For automatic detection, systems should be developed that can track pilot activity, infer pilot intent and inform the crew of potential errors before their consequences are realized. Systems that perform a reasonableness check on flight plan modifications by checking route length and magnitude of course changes are simple examples. Another example would be a system that checked the aircraft's planned altitude against a data base of world terrain elevations. Information is given in viewgraph form.
Safety climate and its association with office type and team involvement in primary care.
Gehring, Katrin; Schwappach, David L B; Battaglia, Markus; Buff, Roman; Huber, Felix; Sauter, Peter; Wieser, Markus
2013-09-01
To assess differences in safety climate perceptions between occupational groups and types of office organization in primary care. Primary care physicians and nurses working in outpatient offices were surveyed about safety climate. Explorative factor analysis was performed to determine the factorial structure. Differences in mean climate scores between staff groups and types of office were tested. Logistic regression analysis was conducted to determine predictors for a 'favorable' safety climate. 630 individuals returned the survey (response rate, 50%). Differences between occupational groups were observed in the means of the 'team-based error prevention'-scale (physician 4.0 vs. nurse 3.8, P < 0.001). Medical centers scored higher compared with single-handed offices and joint practices on the 'team-based error prevention'-scale (4.3 vs. 3.8 vs. 3.9, P < 0.001) but less favorable on the 'rules and risks'-scale (3.5 vs. 3.9 vs. 3.7, P < 0.001). Characteristics on the individual and office level predicted favorable 'team-based error prevention'-scores. Physicians (OR = 0.4, P = 0.01) and less experienced staff (OR 0.52, P = 0.04) were less likely to provide favorable scores. Individuals working at medical centers were more likely to provide positive scores compared with single-handed offices (OR 3.33, P = 0.001). The largest positive effect was associated with at least monthly team meetings (OR 6.2, P < 0.001) and participation in quality circles (OR 4.49, P < 0.001). Results indicate that frequent quality circle participation and team meetings involving all team members are effective ways to strengthen safety climate in terms of team-based strategies and activities in error prevention.
Blending Two Major Techniques in Order to Compute [Pi
ERIC Educational Resources Information Center
Guasti, M. Fernandez
2005-01-01
Three major techniques are employed to calculate [pi]. Namely, (i) the perimeter of polygons inscribed or circumscribed in a circle, (ii) calculus based methods using integral representations of inverse trigonometric functions, and (iii) modular identities derived from the transformation theory of elliptic integrals. This note presents a…
Experiential Learning in Marketing Communications Courses: The Demarketing of College Binge-Drinking
ERIC Educational Resources Information Center
Rozensher, Susan G.; Seal, David S.
2009-01-01
The experiential learning approach has been gathering substantial momentum and support in educational circles. In the team-based experiential learning project presented here, which effectively integrated theory and application, students were charged with creating an integrated marketing communications plan to demarket binge drinking on the college…
Quantum transport in chaotic and integrable ballistic cavities with tunable shape
NASA Astrophysics Data System (ADS)
Lee, Y.; Faini, G.; Mailly, D.
1997-10-01
We have performed magnetotransport measurements in ballistic cavities and obtained the average by small modulations on the shapes and/or on the Fermi level. We work with cavities whose underlying classical dynamics is chaotic (stadia and Sinaï billiards) and integrable (circles and rectangles). The former show a Lorentzian weak-localization peak, in agreement with semiclassical predictions and other averaging methods that have been used in recent measurements. For integrable cavities our measurements show that the shape of the weak localization is very sensitive to the exact geometry of the sample: a linear magnetoconductance has been observed for rectangles as expected by the theory for integrable cavities, whereas for circles the shape is always Lorentzian. These discrepancies illustrate the nongeneric behavior of scattering through integrable geometries, that we analyze taking into account the interplay of integrability with smooth disorder and geometrical effects. The power spectra of the conductance fluctuations are also analyzed, the deduced typical areas are in good agreement with those obtained from the weak localization. Periodic orbits in nonaveraged Fourier transforms of the magnetoconductance for regular cavities are clearly identified indicating the good quality of our samples.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu Ke; Li Yanqiu; Wang Hai
Characterization of measurement accuracy of the phase-shifting point diffraction interferometer (PS/PDI) is usually performed by two-pinhole null test. In this procedure, the geometrical coma and detector tilt astigmatism systematic errors are almost one or two magnitude higher than the desired accuracy of PS/PDI. These errors must be accurately removed from the null test result to achieve high accuracy. Published calibration methods, which can remove the geometrical coma error successfully, have some limitations in calibrating the astigmatism error. In this paper, we propose a method to simultaneously calibrate the geometrical coma and detector tilt astigmatism errors in PS/PDI null test. Basedmore » on the measurement results obtained from two pinhole pairs in orthogonal directions, the method utilizes the orthogonal and rotational symmetry properties of Zernike polynomials over unit circle to calculate the systematic errors introduced in null test of PS/PDI. The experiment using PS/PDI operated at visible light is performed to verify the method. The results show that the method is effective in isolating the systematic errors of PS/PDI and the measurement accuracy of the calibrated PS/PDI is 0.0088{lambda} rms ({lambda}= 632.8 nm).« less
Ye, Jingfei; Gao, Zhishan; Wang, Shuai; Cheng, Jinlong; Wang, Wei; Sun, Wenqing
2014-10-01
Four orthogonal polynomials for reconstructing a wavefront over a square aperture based on the modal method are currently available, namely, the 2D Chebyshev polynomials, 2D Legendre polynomials, Zernike square polynomials and Numerical polynomials. They are all orthogonal over the full unit square domain. 2D Chebyshev polynomials are defined by the product of Chebyshev polynomials in x and y variables, as are 2D Legendre polynomials. Zernike square polynomials are derived by the Gram-Schmidt orthogonalization process, where the integration region across the full unit square is circumscribed outside the unit circle. Numerical polynomials are obtained by numerical calculation. The presented study is to compare these four orthogonal polynomials by theoretical analysis and numerical experiments from the aspects of reconstruction accuracy, remaining errors, and robustness. Results show that the Numerical orthogonal polynomial is superior to the other three polynomials because of its high accuracy and robustness even in the case of a wavefront with incomplete data.
Cortical Integration of Audio-Visual Information
Vander Wyk, Brent C.; Ramsay, Gordon J.; Hudac, Caitlin M.; Jones, Warren; Lin, David; Klin, Ami; Lee, Su Mei; Pelphrey, Kevin A.
2013-01-01
We investigated the neural basis of audio-visual processing in speech and non-speech stimuli. Physically identical auditory stimuli (speech and sinusoidal tones) and visual stimuli (animated circles and ellipses) were used in this fMRI experiment. Relative to unimodal stimuli, each of the multimodal conjunctions showed increased activation in largely non-overlapping areas. The conjunction of Ellipse and Speech, which most resembles naturalistic audiovisual speech, showed higher activation in the right inferior frontal gyrus, fusiform gyri, left posterior superior temporal sulcus, and lateral occipital cortex. The conjunction of Circle and Tone, an arbitrary audio-visual pairing with no speech association, activated middle temporal gyri and lateral occipital cortex. The conjunction of Circle and Speech showed activation in lateral occipital cortex, and the conjunction of Ellipse and Tone did not show increased activation relative to unimodal stimuli. Further analysis revealed that middle temporal regions, although identified as multimodal only in the Circle-Tone condition, were more strongly active to Ellipse-Speech or Circle-Speech, but regions that were identified as multimodal for Ellipse-Speech were always strongest for Ellipse-Speech. Our results suggest that combinations of auditory and visual stimuli may together be processed by different cortical networks, depending on the extent to which speech or non-speech percepts are evoked. PMID:20709442
Reconfigurable Cellular Photonic Crystal Arrays (RCPA)
2013-03-01
signal processing based on reconfigurable integrated optics devices. This technology has the potential to revolutionize the design circle of optical...Accomplishments III.A. Design and fabrication of an accumulation-mode modulator Figure 1(a) shows the schematic of a compact resonator on the double-Si... integration of silicon nitride on silicon-on-insulator platform to enhance the arsenal of photonic circuit designers . The coherent integration of
Socializing Respect and Knowledge in a Racially Integrated Science Classroom
ERIC Educational Resources Information Center
Solis, Jorge; Kattan, Shlomy; Baquedano-Lopez, Patricia
2009-01-01
In this article we examine the socialization of respect in a racially integrated science classroom in Northern California that employed a character education program called Tribes. We focus on the ways scripts derived from this program are enacted during Community Circle activities and how breaches to these scripts and the norms of respectful…
Social Work Science and Identity Formation for Doctoral Scholars within Intellectual Communities
ERIC Educational Resources Information Center
Mor Barak, Michàlle E.; Brekke, John S.
2014-01-01
Three themes are central to preparing doctoral students for the professoriate: identity formation, scientific integration, and intellectual communities. In this article, we argue that these three themes are not separate pillars but interlocking circles. Our main thesis is that (1) social work must develop into a distinct integrative scientific…
Clausson, Carl-Magnus; Arngården, Linda; Ishaq, Omer; Klaesson, Axel; Kühnemund, Malte; Grannas, Karin; Koos, Björn; Qian, Xiaoyan; Ranefall, Petter; Krzywkowski, Tomasz; Brismar, Hjalmar; Nilsson, Mats; Wählby, Carolina; Söderberg, Ola
2015-01-01
Rolling circle amplification (RCA) for generation of distinct fluorescent signals in situ relies upon the self-collapsing properties of single-stranded DNA in commonly used RCA-based methods. By introducing a cross-hybridizing DNA oligonucleotide during rolling circle amplification, we demonstrate that the fluorophore-labeled RCA products (RCPs) become smaller. The reduced size of RCPs increases the local concentration of fluorophores and as a result, the signal intensity increases together with the signal-to-noise ratio. Furthermore, we have found that RCPs sometimes tend to disintegrate and may be recorded as several RCPs, a trait that is prevented with our cross-hybridizing DNA oligonucleotide. These effects generated by compaction of RCPs improve accuracy of visual as well as automated in situ analysis for RCA based methods, such as proximity ligation assays (PLA) and padlock probes. PMID:26202090
Quantum localisation on the circle
NASA Astrophysics Data System (ADS)
Fresneda, Rodrigo; Gazeau, Jean Pierre; Noguera, Diego
2018-05-01
Covariant integral quantisation using coherent states for semi-direct product groups is implemented for the motion of a particle on the circle. In this case, the phase space is the cylinder, which is viewed as a left coset of the Euclidean group E(2). Coherent states issued from fiducial vectors are labeled by points in the cylinder and depend also on extra parameters. We carry out the corresponding quantisations of the basic classical observables, particularly the angular momentum and the 2π-periodic discontinuous angle function. We compute their corresponding lower symbols. The quantum localisation on the circle is examined through the properties of the angle operator yielded by our procedure, its spectrum and lower symbol, its commutator with the quantum angular momentum, and the resulting Heisenberg inequality. Comparison with other approaches to the long-standing question of the quantum angle is discussed.
Self-localization for an autonomous mobile robot based on an omni-directional vision system
NASA Astrophysics Data System (ADS)
Chiang, Shu-Yin; Lin, Kuang-Yu; Chia, Tsorng-Lin
2013-12-01
In this study, we designed an autonomous mobile robot based on the rules of the Federation of International Robotsoccer Association (FIRA) RoboSot category, integrating the techniques of computer vision, real-time image processing, dynamic target tracking, wireless communication, self-localization, motion control, path planning, and control strategy to achieve the contest goal. The self-localization scheme of the mobile robot is based on the algorithms featured in the images from its omni-directional vision system. In previous works, we used the image colors of the field goals as reference points, combining either dual-circle or trilateration positioning of the reference points to achieve selflocalization of the autonomous mobile robot. However, because the image of the game field is easily affected by ambient light, positioning systems exclusively based on color model algorithms cause errors. To reduce environmental effects and achieve the self-localization of the robot, the proposed algorithm is applied in assessing the corners of field lines by using an omni-directional vision system. Particularly in the mid-size league of the RobotCup soccer competition, selflocalization algorithms based on extracting white lines from the soccer field have become increasingly popular. Moreover, white lines are less influenced by light than are the color model of the goals. Therefore, we propose an algorithm that transforms the omni-directional image into an unwrapped transformed image, enhancing the extraction features. The process is described as follows: First, radical scan-lines were used to process omni-directional images, reducing the computational load and improving system efficiency. The lines were radically arranged around the center of the omni-directional camera image, resulting in a shorter computational time compared with the traditional Cartesian coordinate system. However, the omni-directional image is a distorted image, which makes it difficult to recognize the position of the robot. Therefore, image transformation was required to implement self-localization. Second, we used an approach to transform the omni-directional images into panoramic images. Hence, the distortion of the white line can be fixed through the transformation. The interest points that form the corners of the landmark were then located using the features from accelerated segment test (FAST) algorithm. In this algorithm, a circle of sixteen pixels surrounding the corner candidate is considered and is a high-speed feature detector in real-time frame rate applications. Finally, the dual-circle, trilateration, and cross-ratio projection algorithms were implemented in choosing the corners obtained from the FAST algorithm and localizing the position of the robot. The results demonstrate that the proposed algorithm is accurate, exhibiting a 2-cm position error in the soccer field measuring 600 cm2 x 400 cm2.
Cursor Control Device Test Battery
NASA Technical Reports Server (NTRS)
Holden, Kritina; Sandor, Aniko; Pace, John; Thompson, Shelby
2013-01-01
The test battery was developed to provide a standard procedure for cursor control device evaluation. The software was built in Visual Basic and consists of nine tasks and a main menu that integrates the set-up of the tasks. The tasks can be used individually, or in a series defined in the main menu. Task 1, the Unidirectional Pointing Task, tests the speed and accuracy of clicking on targets. Two rectangles with an adjustable width and adjustable center- to-center distance are presented. The task is to click back and forth between the two rectangles. Clicks outside of the rectangles are recorded as errors. Task 2, Multidirectional Pointing Task, measures speed and accuracy of clicking on targets approached from different angles. Twenty-five numbered squares of adjustable width are arranged around an adjustable diameter circle. The task is to point and click on the numbered squares (placed on opposite sides of the circle) in consecutive order. Clicks outside of the squares are recorded as errors. Task 3, Unidirectional (horizontal) Dragging Task, is similar to dragging a file into a folder on a computer desktop. Task 3 requires dragging a square of adjustable width from one rectangle and dropping it into another. The width of each rectangle is adjustable, as well as the distance between the two rectangles. Dropping the square outside of the rectangles is recorded as an error. Task 4, Unidirectional Path Following, is similar to Task 3. The task is to drag a square through a tunnel consisting of two lines. The size of the square and the width of the tunnel are adjustable. If the square touches any of the lines, it is counted as an error and the task is restarted. Task 5, Text Selection, involves clicking on a Start button, and then moving directly to the underlined portion of the displayed text and highlighting it. The pointing distance to the text is adjustable, as well as the to-be-selected font size and the underlined character length. If the selection does not include all of the underlined characters, or includes non-underlined characters, it is recorded as an error. Task 6, Multi-size and Multi-distance Pointing, presents the participant with 24 consecutively numbered buttons of different sizes (63 to 163 pixels), and at different distances (60 to 80 pixels) from the Start button. The task is to click on the Start button, and then move directly to, and click on, each numbered target button in consecutive order. Clicks outside of the target area are errors. Task 7, Standard Interface Elements Task, involves interacting with standard interface elements as instructed in written procedures, including: drop-down menus, sliders, text boxes, radio buttons, and check boxes. Task completion time is recorded. In Task 8, a circular track is presented with a disc in it at the top. Track width and disc size are adjustable. The task is to move the disc with circular motion within the path without touching the boundaries of the track. Time and errors are recorded. Task 9 is a discrete task that allows evaluation of discrete cursor control devices that tab from target to target, such as a castle switch. The task is to follow a predefined path and to click on the yellow targets along the path.
Derbyshire, Brian; Raut, Videshnandan V.
2013-01-01
Historically, wire markers were attached to cemented all-plastic acetabular cups to demarcate the periphery and to measure socket wear. The wire shape was either a semi-circle passing over the pole of the cup, or a circle around the cup equator. More recently, “double-D” shaped markers were introduced with a part-circular aspect passing over the pole and a semi-circular aspect parallel to the equatorial plane. This configuration enabled cup retroversion to be distinguished from anteversion. In this study, the accuracy of radiographic measurement of cup orientation and wear was assessed for cups with “double-D” and circular markers. Each cup was attached to a measurement jig which could vary the anteversion/retroversion and internal/external rotation of the cup. A metal femoral head was fixed within the socket and radiographic images were created for all combinations of cup orientation settings. The images were measured using software with automatic edge detection, and cup orientation and zero-wear accuracies were determined for each setting. The median error for cup version measurements was similar for both types of wire marker (0.2° double-D marker, −0.24° circular marker), but measurements of the circular marker were more repeatable. The median inclination errors were 2.05° (double-D marker) and 0.23° (circular marker). The median overall “zero wear” errors were 0.19 mm (double-D marker) and 0.03 mm (circular marker). Measurements of the circular wire marker were much more repeatable. PMID:23813165
ERIC Educational Resources Information Center
Stupel, Moshe; Segal, Ruti; Oxman, Victor
2016-01-01
In this article, we present investigative tasks that concern loci, which integrate the use of dynamic geometry software (DGS) with mathematics for proving the obtained figures. Additional conditions were added to the loci: ellipse, parabola and circle, which result in the emergence of new loci, similar in form to the original loci. The…
Rennke, Stephanie; Yuan, Patrick; Monash, Brad; Blankenburg, Rebecca; Chua, Ian; Harman, Stephanie; Sakai, Debbie S; Khan, Adeena; Hilton, Joan F; Shieh, Lisa; Satterfield, Jason
2017-12-01
Patient engagement through shared decision-making (SDM) is increasingly seen as a key component for patient safety, patient satisfaction, and quality of care. Current SDM models do not adequately account for medical and environmental contexts, which may influence medical decisions in the hospital. We identified leading SDM models and reviews to inductively construct a novel SDM model appropriate for the inpatient setting. A team of medicine and pediatric hospitalists reviewed the literature to integrate core SDM concepts and processes and iteratively constructed a synthesized draft model. We then solicited broad SDM expert feedback on the draft model for validation and further refinement. The SDM 3 Circle Model identifies 3 core categories of variables that dynamically interact within an "environmental frame." The resulting Venn diagram includes overlapping circles for (1) patient/family, (2) provider/team, and (3) medical context. The environmental frame includes all external, contextual factors that may influence any of the 3 circles. Existing multistep SDM process models were then rearticulated and contextualized to illustrate how a shared decision might be made. The SDM 3 Circle Model accounts for important environmental and contextual characteristics that vary across settings. The visual emphasis generated by each "circle" and by the environmental frame direct attention to often overlooked interactive forces and has the potential to more precisely define, promote, and improve SDM. This model provides a framework to develop interventions to improve quality and patient safety through SDM and patient engagement for hospitalists. © 2017 Society of Hospital Medicine.
Lin, Ming-Yu; Hsu, Wen-Yang; Yang, Yuh-Shyong; Huang, Jo-Wen; Chung, Yueh-Lin; Chen, Hsin
2016-07-01
Detection of tumor-related proteins with high specificity and sensitivity is important for early diagnosis and prognosis of cancers. While protein sensors based on antibodies are not easy to keep for a long time, aptamers (single-stranded DNA) are found to be a good alternative for recognizing tumor-related protein specifically. This study investigates the feasibility of employing aptamers to recognize the platelet-derived growth factor (PDGF) specifically and subsequently triggering rolling circle amplification (RCA) of DNAs on extended-gate field-effect transistors (EGFETs) to enhance the sensitivity. The EGFETs are fabricated by the standard CMOS technology and integrated with readout circuits monolithically. The monolithic integration not only avoids the wiring complexity for a large sensor array but also enhances the sensor reliability and facilitates massive production for commercialization. With the RCA primers immobilized on the sensory surface, the protein signal is amplified as the elongation of DNA, allowing the EGFET to achieve a sensitivity of 8.8 pM, more than three orders better than that achieved by conventional EGFETs. Moreover, the responses of EGFETs are able to indicate quantitatively the reaction rates of RCA, facilitating the estimation on the protein concentration. Our experimental results demonstrate that immobilized RCA on EGFETs is a useful, label-free method for early diagnosis of diseases related to low-concentrated tumor makers (e.g., PDGF) for serum sample, as well as for monitoring the synthesis of various DNA nanostructures in real time. Graphical Abstract The tumor-related protein, PDGF, is detected by immobilizing rolling circle amplification on an EGFET with integrated readout circuit.
NASA Astrophysics Data System (ADS)
Waeldele, F.
1983-01-01
The influence of sample shape deviations on the measurement uncertainties and the optimization of computer aided coordinate measurement were investigated for a circle and a cylinder. Using the complete error propagation law in matrix form the parameter uncertainties are calculated, taking the correlation between the measurement points into account. Theoretical investigations show that the measuring points have to be equidistantly distributed and that for a cylindrical body a measuring point distribution along a cross section is better than along a helical line. The theoretically obtained expressions to calculate the uncertainties prove to be a good estimation basis. The simple error theory is not satisfactory for estimation. The complete statistical data analysis theory helps to avoid aggravating measurement errors and to adjust the number of measuring points to the required measuring uncertainty.
Farkas, Alexandra; Száz, Dénes; Egri, Ádám; Blahó, Miklós; Barta, András; Nehéz, Dóra; Bernáth, Balázs; Horváth, Gábor
2014-07-01
It is a widely discussed hypothesis that Viking seafarers might have been able to locate the position of the occluded sun by means of dichroic or birefringent crystals, the mysterious sunstones, with which they could analyze skylight polarization. Although the atmospheric optical prerequisites and certain aspects of the efficiency of this sky-polarimetric Viking navigation have been investigated, the accuracy of the main steps of this method has not been quantitatively examined. To fill in this gap, we present here the results of a planetarium experiment in which we measured the azimuth and elevation errors of localization of the invisible sun. In the planetarium sun localization was performed in two selected celestial points on the basis of the alignments of two small sections of two celestial great circles passing through the sun. In the second step of sky-polarimetric Viking navigation the navigator needed to determine the intersection of two such celestial circles. We found that the position of the sun (solar elevation θ(S), solar azimuth φ(S)) was estimated with an average error of +0.6°≤Δθ≤+8.8° and -3.9°≤Δφ≤+2.0°. We also calculated the compass direction error when the estimated sun position is used for orienting with a Viking sun-compass. The northern direction (ω(North)) was determined with an error of -3.34°≤Δω(North)≤+6.29°. The inaccuracy of the second step of this navigation method was high (Δω(North)=-16.3°) when the solar elevation was 5°≤θ(S)≤25°, and the two selected celestial points were far from the sun (at angular distances 95°≤γ(1), γ(2)≤115°) and each other (125°≤δ≤145°). Considering only this second step, the sky-polarimetric navigation could be more accurate in the mid-summer period (June and July), when in the daytime the sun is high above the horizon for long periods. In the spring (and autumn) equinoctial period, alternative methods (using a twilight board, for example) might be more appropriate. Since Viking navigators surely also committed further errors in the first and third steps, the orientation errors presented here underestimate the net error of the whole sky-polarimetric navigation.
NASA Astrophysics Data System (ADS)
Zhang, Shaojun; Xu, Xiping
2015-10-01
The 360-degree and all round looking camera, as its characteristics of suitable for automatic analysis and judgment on the ambient environment of the carrier by image recognition algorithm, is usually applied to opto-electronic radar of robots and smart cars. In order to ensure the stability and consistency of image processing results of mass production, it is necessary to make sure the centers of image planes of different cameras are coincident, which requires to calibrate the position of the image plane's center. The traditional mechanical calibration method and electronic adjusting mode of inputting the offsets manually, both exist the problem of relying on human eyes, inefficiency and large range of error distribution. In this paper, an approach of auto- calibration of the image plane of this camera is presented. The imaging of the 360-degree and all round looking camera is a ring-shaped image consisting of two concentric circles, the center of the image is a smaller circle and the outside is a bigger circle. The realization of the technology is just to exploit the above characteristics. Recognizing the two circles through HOUGH TRANSFORM algorithm and calculating the center position, we can get the accurate center of image, that the deviation of the central location of the optic axis and image sensor. The program will set up the image sensor chip through I2C bus automatically, we can adjusting the center of the image plane automatically and accurately. The technique has been applied to practice, promotes productivity and guarantees the consistent quality of products.
Three paths toward the quantum angle operator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gazeau, Jean Pierre, E-mail: gazeau@apc.univ-paris7.fr; Szafraniec, Franciszek Hugon, E-mail: franciszek.szafraniec@uj.edu.pl
2016-12-15
We examine mathematical questions around angle (or phase) operator associated with a number operator through a short list of basic requirements. We implement three methods of construction of quantum angle. The first one is based on operator theory and parallels the definition of angle for the upper half-circle through its cosine and completed by a sign inversion. The two other methods are integral quantization generalizing in a certain sense the Berezin–Klauder approaches. One method pertains to Weyl–Heisenberg integral quantization of the plane viewed as the phase space of the motion on the line. It depends on a family of “weight”more » functions on the plane. The third method rests upon coherent state quantization of the cylinder viewed as the phase space of the motion on the circle. The construction of these coherent states depends on a family of probability distributions on the line.« less
NASA Astrophysics Data System (ADS)
Brinkhuis, D.; Peart, L.
2012-12-01
Scientific discourse generally takes place in appropriate journals, using the language and conventions of science. That's fine, as long as the discourse remains in scientific circles. It is only outside those circles that the rules and techniques of engaging social media tools gain importance. A young generation of scientists are eager to share their experiences by using social media, but is this effective? And how can we better integrate all outreach & media channels to engage general audiences? How can Facebook, Twitter, Skype and YouTube be used as synergy tools in scientific story telling? Case: during IODP Expedtion 342 (June-July 2012) onboard the scientific drillship JOIDES Resolution an onboard educator and videographer worked non-stop fort two months on an integrated outreach plan that tried and tested the limits of all social media tools available to interact with an international public while at sea. The results are spectacular!
Lavie, N
1997-05-01
Predictions from Treisman's feature integration theory of attention were tested in a variant of the response-competition paradigm. Subjects made choice responses to particular color-shape conjunctions (e.g., a purple cross vs. a green circle) while withholding their responses to the opposite conjunctions (i.e., a purple circle vs. a green cross). The results showed that compatibility effects were based on both distractor color and shape. For unattended distractors in preknown irrelevant positions, compatibility effects were equivalent for conjunctive distractors (e.g., a purple cross and a blue triangle) and for disjunctive distractors (e.g., a purple triangle and a blue cross). Manipulation of attention to the distractors positions resulted in larger compatibility effects from conjoined features. These results accord with Treisman's claim that correct conjunction information is unavailable under conditions of inattention, and they provide new information on response-competition effects from multiple features.
Corker, Harry P; Singh, Pritam; Sodergren, Mikael H; Balaji, Sathyan; Kwasnicki, Richard M; Darzi, Ara W; Paraskeva, Paraskevas
2015-01-01
In single-incision laparoscopic surgery (SILS), operating through 1 incision presents ergonomic challenges. No consensus exists on whether articulating instruments (ARTs) may help. This study evaluated their effect on simulated SILS, hypothesizing that they would affect performance and workload. Surgeons were randomized to 2 straight instruments (STRs), 1 ART and 1 STR, or 2 ARTs. After baseline testing, 25 repetitions of the Fundamentals of Laparoscopic Surgery (FLS) peg-transfer (PEG) task and 5 repetitions of the short-hand for the FLS pattern-cutting task (CIRCLE) were performed. Primary outcomes were maximum FLS PEG scores, CIRCLE times and errors, and Imperial College Surgical Assessment Device hand motion analysis. National Aeronautics and Space Administration (NASA) Raw Task Load Index (RTLX) questionnaires evaluated a secondary outcome--workload. The trial took place in a simulated operating theater within the Academic Surgical Unit at St Mary's Hospital, London, UK. Eligible surgeons had completed at least 5 laparoscopic cases as a primary operator. Surgeons were stratified by laparoscopic experience into intermediate (less than 25 previous procedures as primary operator) or advanced (25 procedures or more). A total of 21 surgeons were recruited and randomized; 7 of them to each instrument combination group. All surgeons completed PEG, and 5 from each group completed CIRCLE. Groups' baseline PEG scores were similar (p = 0.625). STR-ART achieved higher maximum PEG scores than STR or ART did (median = 236 vs 198 vs 193, respectively, p = 0.002). Fastest CIRCLE times were similar (median = 190s vs 130s vs 186s, p = 0.129) as were minimum errors (median = 1 vs 2 vs 3, p = 0.101). For PEG, Imperial College Surgical Assessment Device demonstrated similar total path lengths (median = 12.3m vs 12.3m vs 16.0m, p = 0.545) and total numbers of movements (median = 89.6 vs 86.4 vs 171, p = 0.080). Groups' NASA Raw Task Load Index scores were similar (p = 0.708). Combining 1 STR and 1 ART improved SILS performance in the PEG task. Therefore, this may be the optimum instrument configuration for use within some clinical SILS applications. Copyright © 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
The Characteristics of Electromagnetic Fields Induced by Different Type Sources
NASA Astrophysics Data System (ADS)
Di, Q.; Fu, C.; Wang, R.; Xu, C.; An, Z.
2011-12-01
Controlled source audio-frequence magnetotelluric (CSAMT) method has played an important role in the shallow exploration (less than 1.5km) in the field of resources, environment and engineering geology. In order to prospect the deeper target, one has to increase the strength of the source and offset. However, the exploration is nearly impossible for the heavy larger power transmitting source used in the deeper prospecting and mountain area. So an EM method using a fixed large power source, such as long bipole current source, two perpendicular "L" shape long bipole current source and large radius circle current source, is beginning to take shape. In order to increase the strength of the source, the length of the transmitting bipole in one direction or in perpendicular directions has to be much larger, such as L=100km, or the radius of the circle current source is much larger. The electric field strength are IL2and IL2/4π separately for long bipole source and circle current source with the same wire length. Just considering the effectiveness of source, the strength of the circle current source is larger than that of long bipole source if is large enough. However, the strength of the electromagnetic signal doesn't totally depend on the transmitting source, the effect of ionosphere on the electromagnetic (EM) field should be considered when observation is carried at a very far (about several thousands kilometers) location away from the source for the long bipole source or the large radius circle current source. We firstly calculate the electromagnetic fields with the traditional controlled source (CSEM) configuration using the integral equation (IE) code developed by our research group for a three layers earth-ionosphere model which consists of ionosphere, atmosphere and earth media. The modeling results agree well with the half space analytical results because the effect of ionosphere for this small scale source can be ignorable, which means the integral equation method is reliable and effective for modeling models including ionosphere, atmosphere and earth media. In order to discuss EM fields' characters for complicate earth-ionosphere media excited by long bipole, "L" shape bipole and circle current sources in the far-field and wave-guide zones, we modeled the frequency responses and decay characters of EM fields for three layers earth-ionosphere model. Because of the effect of ionosphere, the earth-ionosphere electromagnetic fields' decay curves with given frequency show that the fields of Ex and Hy , excited by a long bipole and "L" shape bipole, can be divided into an extra wave-guide field with slower attenuation and strong amplititude than that in half space, but the EM fields of circle current source does not show the same characteristics, ionosphere makes the amplitude of the EM field weaker for the circle current source. For this reason, it is better to use long bipole source while working in the wave-guide field with a fixed large power source.
Flow tilt angle measurements using lidar anemometry
NASA Astrophysics Data System (ADS)
Dellwik, Ebba; Mann, Jakob
2010-05-01
A new way of estimating near-surface mean flow tilt angles from ground based Doppler lidar measurements is presented. The results are compared with traditional mast based in-situ sonic anemometry. The tilt angle assessed with the lidar is based on 10 or 30 minute mean values of the velocity field from a conically scanning lidar. In this mode of measurement, the lidar beam is rotated in a circle by a prism with a fixed angle to the vertical at varying focus distances. By fitting a trigonometric function to the scans, the mean vertical velocity can be estimated. Lidar measurements from (1) a fetch-limited beech forest site taken at 48-175m above ground level, (2) a reference site in flat agricultural terrain and (3) a second reference site in very complex terrain are presented. The method to derive flow tilt angles and mean vertical velocities from lidar has several advantages compared to sonic anemometry; there is no flow distortion caused by the instrument itself, there are no temperature effects and the instrument misalignment can be corrected for by comparing tilt estimates at various heights. Contrary to mast-based instruments, the lidar measures the wind field with the exact same alignment error at a multitude of heights. Disadvantages with estimating vertical velocities from a lidar compared to mast-based measurements are slightly increased levels of statistical errors due to limited sampling time, because the sampling is disjunct and a requirement for homogeneous flow. The estimated mean vertical velocity is biased if the flow over the scanned circle is not homogeneous. However, the error on the mean vertical velocity due to flow inhomogeneity can be approximated by a function of the angle of the lidar beam to the vertical, the measurement height and the vertical gradient of the mean vertical velocity, whereas the error due to flow inhomogeneity on the horizontal mean wind speed is independent of the lidar beam angle. For the presented measurements over forest, it is evaluated that the systematic error due to the inhomogeneity of the flow is less than 0.2 degrees. Other possibilities for utilizing lidars for flow tilt angle and mean vertical velocities are discussed.
Unstable spiral modes in disk-shaped galaxies
Lau, Y. Y.; Lin, C. C.; Mark, James W.-K.
1976-01-01
The mechanisms for the maintenance and the excitation of trailing spiral modes of density waves in diskshaped galaxies, as proposed by Lin in 1969 and by Mark recently, are substantiated by an analysis of the gas-dynamical model of the galaxy. The self-excitation of the unstable mode in caused by waves propagating outwards from the corotation circle, which carry away angular momentum of a sign opposite to that contained in the wave system inside that circle. Specifically, a simple dispersion relationship is given as a definite integral, which allows the immediate determination of the pattern frequency and the amplification rate, once the basic galactic model is known. PMID:16592313
Swift Follow up observation of the transient source Fermi J1654-1055 (PMN J1632-1052)
NASA Astrophysics Data System (ADS)
Ajello, M.; Kocevski, D.; Buson, S.; Buehler, R.; Giomi, M.
2016-02-01
On February 25, 2016, Swift carried out a 2ks target of opportunity observation of the transient Fermi J1654-1055 (see ATel #8721). Only one source is clearly detected, within the LAT error circle, by the Swift X-ray telescope (XRT) at RA, Dec= 16h 32m 49.9s, -10d 52' 30.1" (J2000) with a 90 % uncertainty radius of 6.3 arcsec.
A rigorous computational approach to linear response
NASA Astrophysics Data System (ADS)
Bahsoun, Wael; Galatolo, Stefano; Nisoli, Isaia; Niu, Xiaolong
2018-03-01
We present a general setting in which the formula describing the linear response of the physical measure of a perturbed system can be obtained. In this general setting we obtain an algorithm to rigorously compute the linear response. We apply our results to expanding circle maps. In particular, we present examples where we compute, up to a pre-specified error in the L∞ -norm, the response of expanding circle maps under stochastic and deterministic perturbations. Moreover, we present an example where we compute, up to a pre-specified error in the L 1-norm, the response of the intermittent family at the boundary; i.e. when the unperturbed system is the doubling map. This work was mainly conducted during a visit of SG to Loughborough University. WB and SG would like to thank The Leverhulme Trust for supporting mutual research visits through the Network Grant IN-2014-021. SG thanks the Department of Mathematical Sciences at Loughborough University for hospitality. WB thanks Dipartimento di Matematica, Universita di Pisa. The research of SG and IN is partially supported by EU Marie-Curie IRSES ‘Brazilian-European partnership in Dynamical Systems’ (FP7-PEOPLE-2012-IRSES 318999 BREUDS). IN was partially supported by CNPq and FAPERJ. IN would like to thank the Department of Mathematics at Uppsala University and the support of the KAW grant 2013.0315.
NASA Astrophysics Data System (ADS)
Borchert, Otto Jerome
This paper describes a software tool to assist groups of people in the classification and identification of real world objects called the Classification, Identification, and Retrieval-based Collaborative Learning Environment (CIRCLE). A thorough literature review identified current pedagogical theories that were synthesized into a series of five tasks: gathering, elaboration, classification, identification, and reinforcement through game play. This approach is detailed as part of an included peer reviewed paper. Motivation is increased through the use of formative and summative gamification; getting points completing important portions of the tasks and playing retrieval learning based games, respectively, which is also included as a peer-reviewed conference proceedings paper. Collaboration is integrated into the experience through specific tasks and communication mediums. Implementation focused on a REST-based client-server architecture. The client is a series of web-based interfaces to complete each of the tasks, support formal classroom interaction through faculty accounts and student tracking, and a module for peers to help each other. The server, developed using an in-house JavaMOO platform, stores relevant project data and serves data through a series of messages implemented as a JavaScript Object Notation Application Programming Interface (JSON API). Through a series of two beta tests and two experiments, it was discovered the second, elaboration, task requires considerable support. While students were able to properly suggest experiments and make observations, the subtask involving cleaning the data for use in CIRCLE required extra support. When supplied with more structured data, students were enthusiastic about the classification and identification tasks, showing marked improvement in usability scores and in open ended survey responses. CIRCLE tracks a variety of educationally relevant variables, facilitating support for instructors and researchers. Future work will revolve around material development, software refinement, and theory building. Curricula, lesson plans, instructional materials need to be created to seamlessly integrate CIRCLE in a variety of courses. Further refinement of the software will focus on improving the elaboration interface and developing further game templates to add to the motivation and retrieval learning aspects of the software. Data gathered from CIRCLE experiments can be used to develop and strengthen theories on teaching and learning.
A tale of two fractals: The Hofstadter butterfly and the integral Apollonian gaskets
NASA Astrophysics Data System (ADS)
Satija, Indubala I.
2016-11-01
This paper unveils a mapping between a quantum fractal that describes a physical phenomena, and an abstract geometrical fractal. The quantum fractal is the Hofstadter butterfly discovered in 1976 in an iconic condensed matter problem of electrons moving in a two-dimensional lattice in a transverse magnetic field. The geometric fractal is the integer Apollonian gasket characterized in terms of a 300 BC problem of mutually tangent circles. Both of these fractals are made up of integers. In the Hofstadter butterfly, these integers encode the topological quantum numbers of quantum Hall conductivity. In the Apollonian gaskets an infinite number of mutually tangent circles are nested inside each other, where each circle has integer curvature. The mapping between these two fractals reveals a hidden D3 symmetry embedded in the kaleidoscopic images that describe the asymptotic scaling properties of the butterfly. This paper also serves as a mini review of these fractals, emphasizing their hierarchical aspects in terms of Farey fractions.
Search asymmetry: a diagnostic for preattentive processing of separable features.
Treisman, A; Souther, J
1985-09-01
The search rate for a target among distractors may vary dramatically depending on which stimulus plays the role of target and which that of distractors. For example, the time required to find a circle distinguished by an intersecting line is independent of the number of regular circles in the display, whereas the time to find a regular circle among circles with lines increases linearly with the number of distractors. The pattern of performance suggests parallel processing when the target has a unique distinguishing feature and serial self-terminating search when the target is distinguished only by the absence of a feature that is present in all the distractors. The results are consistent with feature-integration theory (Treisman & Gelade, 1980), which predicts that a single feature should be detected by the mere presence of activity in the relevant feature map, whereas tasks that require subjects to locate multiple instances of a feature demand focused attention. Search asymmetries may therefore offer a new diagnostic to identify the primitive features of early vision. Several candidate features are examined in this article: Colors, line ends or terminators, and closure (in the sense of a partly or wholly enclosed area) appear to be functional features; connectedness, intactness (absence of an intersecting line), and acute angles do not.
Palliative wound care management strategies for palliative patients and their circles of care.
Woo, Kevin Y; Krasner, Diane L; Kennedy, Bruce; Wardle, David; Moir, Olivia
2015-03-01
To provide information about palliative wound care management strategies for palliative patients and their circles of care. This continuing education activity is intended for physicians and nurses with an interest in skin and wound care. After participating in this educational activity, the participant should be better able to: 1. Recognize study findings, assessment tools, and non-pharmacologic strategies used for patients with palliative wounds. 2. Summarize pharmacologic and dressing treatment strategies used for wound care management of palliative patients. The principles of palliative wound care should be integrated along the continuum of wound care to address the whole person care needs of palliative patients and their circles of care, which includes members of the patient unit including family, significant others, caregivers, and other healthcare professionals that may be external to the current interprofessional team. Palliative patients often present with chronic debilitating diseases, advanced diseases associated with major organ failure (renal, hepatic, pulmonary, or cardiac), profound dementia, complex psychosocial issues, diminished self-care abilities, and challenging wound-related symptoms. This article introduces key concepts and strategies for palliative wound care that are essential for interprofessional team members to incorporate in clinical practice when caring for palliative patients with wounds and their circles of care.
ERIC Educational Resources Information Center
Merkel, Jeanean
1998-01-01
States that people feel spiritual longing, expressed in belief in a God or higher power, to feel whole in a fragmented society. Recommends setting aside a sacred space, being still, and finding a spiritual community as rituals to reconnect with God and integrate the inner and outer lives. (VWC)
[CIRRNET® - learning from errors, a success story].
Frank, O; Hochreutener, M; Wiederkehr, P; Staender, S
2012-06-01
CIRRNET® is the network of local error-reporting systems of the Swiss Patient Safety Foundation. The network has been running since 2006 together with the Swiss Society for Anaesthesiology and Resuscitation (SGAR), and network participants currently include 39 healthcare institutions from all four different language regions of Switzerland. Further institutions can join at any time. Local error reports in CIRRNET® are bundled at a supraregional level, categorised in accordance with the WHO classification, and analysed by medical experts. The CIRRNET® database offers a solid pool of data with error reports from a wide range of medical specialist's areas and provides the basis for identifying relevant problem areas in patient safety. These problem areas are then processed in cooperation with specialists with extremely varied areas of expertise, and recommendations for avoiding these errors are developed by changing care processes (Quick-Alerts®). Having been approved by medical associations and professional medical societies, Quick-Alerts® are widely supported and well accepted in professional circles. The CIRRNET® database also enables any affiliated CIRRNET® participant to access all error reports in the 'closed user area' of the CIRRNET® homepage and to use these error reports for in-house training. A healthcare institution does not have to make every mistake itself - it can learn from the errors of others, compare notes with other healthcare institutions, and use existing knowledge to advance its own patient safety.
An evaluation of programmed treatment-integrity errors during discrete-trial instruction.
Carroll, Regina A; Kodak, Tiffany; Fisher, Wayne W
2013-01-01
This study evaluated the effects of programmed treatment-integrity errors on skill acquisition for children with an autism spectrum disorder (ASD) during discrete-trial instruction (DTI). In Study 1, we identified common treatment-integrity errors that occur during academic instruction in schools. In Study 2, we simultaneously manipulated 3 integrity errors during DTI. In Study 3, we evaluated the effects of each of the 3 integrity errors separately on skill acquisition during DTI. Results showed that participants either demonstrated slower skill acquisition or did not acquire the target skills when instruction included treatment-integrity errors. © Society for the Experimental Analysis of Behavior.
Extragalactic counterparts to Einstein slew survey sources
NASA Technical Reports Server (NTRS)
Schachter, Jonathan F.; Elvis, Martin; Plummer, David; Remillard, Ron
1992-01-01
The Einstein slew survey consists of 819 bright X-ray sources, of which 636 (or 78 percent) are identified with counterparts in standard catalogs. The importance of bright X-ray surveys is stressed, and the slew survey is compared to the Rosat all sky survey. Statistical techniques for minimizing confusion in arcminute error circles in digitized data are discussed. The 238 slew survey active galactic nuclei, clusters, and BL Lacertae objects identified to date and their implications for logN-logS and source evolution studies are described.
Observations of the star Cor Caroli at the Apple Valley Workshop 2016
NASA Astrophysics Data System (ADS)
Estrada, Reed; Boyd, Sidney; Estrada, Chris; Evans, Cody; Rhoades, Hannah; Rhoades, Mark; Rhoades, Trevor
2017-06-01
Using a 22-inch Newtonian Alt/Az telescope and Celestron Micro Guide eyepiece, students participating in a workshop observed the binary star Cor Caroli (STF 1692) and found a position angle of 231.0 degrees as well as an average separation of 18.7" This observation compared favorably with the 2015 Washington Double Star published position. This project was part of Mark Brewer's Apple Valley Double Star Workshop. The results were analyzed using bias and circle error probability calculations.
Swift J1822.3-1606: Optical spectroscopy of the counterpart candidates from the 10.4m GTC
NASA Astrophysics Data System (ADS)
de Ugarte Postigo, A.; Munoz-Darias, T.
2011-07-01
We have performed optical spectroscopy of the two objects (S1 and S2; ATEL #3496, #3502) present within the Swift/XRT error circle of the Soft Gamma-ray Repeater (SGR) candidate, Swift J1822.3-1606 (ATEL #3488, #3489, #3490, #3491, #3493, #3501, #3503). Observations were performed on July 20, 2011 using the OSIRIS spectrograph at the 10.4m Gran Telescopio de Canarias (GTC) telescope in La Palma, Spain.
Identifications of Four Integral Sources in the Galactic Plane via CHANDRA Localizations
NASA Technical Reports Server (NTRS)
Tomsick, John A.; Chaty, Sylvain; Rodriquez, Jerome; Foschini, Luigi; Walter, Roland; Kaaret, Philip
2006-01-01
Hard X-ray imaging of the Galactic plane by the INTEGRAL satellite is uncovering large numbers of 20-100 keV "IGR" sources. We present results from Chandra, INTEGRAL, optical, and IR observations of four IGR sources: three sources in the Norma region of the Galaxy(1GR J16195-4945,IGR J16207-5129, and IGR J16167-4957) and one that is closer to the Galactic center (IGR 5171 95-4100). In all four cases, one relatively bright Chandra source is seen in the INTEGRAL error circle, and these are likely to be the soft X-ray counterparts of the IGR sources. They have hard 0.3-10 keV spectra with power-law photon indices of Gamma = 0.5-1.1. While many previously studied IGR sources show high column densities (NH approx. 10(exp 23)-10(exp 24)/sq cm), only IGR J16195-4945 has a column density that could be as high as 10(exp 23)/sq cm. Using optical and IR sky survey catalogs and our own photometry, we have obtained identifications for all four sources. The J-band magnitudes are in the range 14.9-10.4, and we have used the optical/IR spectral energy distributions (SEDs) to constrain the nature of the sources. Blackbody components with temperature lower limits of >9400 K for IGR J16195-4945 and >18,000 K for IGR J16207-5129 indicate that these are very likely high-mass X-ray binaries (HMXBs). However, for IGR 516167-4957 and IGR J17195-4100, low extinction and the SEDs indicate later spectral types for the putative companions, suggesting that these are not HMXBs.
Binding blocks: building the Universe one nucleus at a time
NASA Astrophysics Data System (ADS)
Diget, C. Aa; Pastore, A.; Leech, K.; Haylett, T.; Lock, S.; Sanders, T.; Shelley, M.; Willett, H. V.; Keegans, J.; Sinclair, L.; Simpson, E. C.; Binding Blocks Collaboration
2017-03-01
We present a new teaching and outreach activity based around the construction of a three-dimensional chart of isotopes using \\text{LEG}{{\\text{O}}\\circledR} bricks5. The activity, binding blocks, demonstrates nuclear and astrophysical processes through a seven-meter chart of all nuclear isotopes, built from over 26 000 \\text{LEG}{{\\text{O}}\\circledR} bricks. It integrates A-Level and GCSE curricula across areas of nuclear physics, astrophysics, and chemistry, including: nuclear decays (through the colours in the chart); nuclear binding energy (through tower heights); production of chemical elements in the cosmos; fusion processes in stars and fusion energy on Earth; as well as links to medical physics, particularly diagnostics and radiotherapy.
Computational approach to compact Riemann surfaces
NASA Astrophysics Data System (ADS)
Frauendiener, Jörg; Klein, Christian
2017-01-01
A purely numerical approach to compact Riemann surfaces starting from plane algebraic curves is presented. The critical points of the algebraic curve are computed via a two-dimensional Newton iteration. The starting values for this iteration are obtained from the resultants with respect to both coordinates of the algebraic curve and a suitable pairing of their zeros. A set of generators of the fundamental group for the complement of these critical points in the complex plane is constructed from circles around these points and connecting lines obtained from a minimal spanning tree. The monodromies are computed by solving the defining equation of the algebraic curve on collocation points along these contours and by analytically continuing the roots. The collocation points are chosen to correspond to Chebychev collocation points for an ensuing Clenshaw-Curtis integration of the holomorphic differentials which gives the periods of the Riemann surface with spectral accuracy. At the singularities of the algebraic curve, Puiseux expansions computed by contour integration on the circles around the singularities are used to identify the holomorphic differentials. The Abel map is also computed with the Clenshaw-Curtis algorithm and contour integrals. As an application of the code, solutions to the Kadomtsev-Petviashvili equation are computed on non-hyperelliptic Riemann surfaces.
Crowding, feature integration, and two kinds of "attention".
Põder, Endel
2006-02-21
In a recent article, Pelli, Palomares, and Majaj (2004) suggested that feature binding is mediated by hard-wired integration fields instead of a spotlight of spatial attention (as assumed by Treisman & Gelade, 1980). Consequently, the correct conjoining of visual features can be guaranteed only when there are no other competing features within a circle with a radius of approximately 0.5E (E = eccentricity of the target object). This claim seems contradicted by an observation that we can easily see--for example, the orientation of a single blue bar within a dense array of randomly oriented red bars. In the present study, possible determinants of the extent of crowding (or feature integration) zones were analyzed with feature (color) singletons as targets. It was found that the number of distractors has a dramatic effect on crowding. With a few distractors, a normal crowding effect was observed. However, by increasing the number of distractors, the crowding effect was remarkably reduced. Similar results were observed when the target and distractors were of the same color and when only a differently colored circle indicated the target location. The results can be explained by bottom-up "attention" that facilitates the processing of information from salient locations in the visual field.
Being a Victim of Medical Error in Brazil: An (Un)Real Dilemma
Mendonça, Vitor Silva; Custódio, Eda Marconi
2016-01-01
Medical error stems from inadequate professional conduct that is capable of producing harm to life or exacerbating the health of another, whether through act or omission. This situation has become increasingly common in Brazil and worldwide. In this study, the aim was to understand what being the victim of medical error is like and to investigate the circumstances imposed on this condition of victims in Brazil. A semi-structured interview was conducted with twelve people who had gone through situations of medical error in their lives, creating a space for narratives of their experiences and deep reflection on the phenomenon. The concept of medical error has a negative connotation, often being associated with the incompetence of a medical professional. Medical error in Brazil is demonstrated by low-quality professional performance and represents the current reality of the country because of the common lack of respect and consideration for patients. Victims often remark on their loss of identity, as their social functions have been interrupted and they do not expect to regain such. It was found, however, little assumption of error in the involved doctors’ discourses and attitudes, which felt a need to judge the medical conduct in an attempt to assert their rights. Medical error in Brazil presents a punitive character and is little discussed in medical and scientific circles. The stigma of medical error is closely connected to the value and cultural judgments of the country, making it difficult to accept, both by victims and professionals. PMID:27403461
Crop circles and organic weed control
USDA-ARS?s Scientific Manuscript database
Organic vegetable production relies on integrated weed control measures to attain satisfactory weed control. An experiment was established in autumn 2010 and 2011 at the North Alabama Horticulture Experiment Station, Cullman, AL. Plot size at both locations was 2.5 by 6 m containing a single row o...
Cross-Clade Ultrasensitive PCR-Based Assays To Measure HIV Persistence in Large-Cohort Studies
Vandergeeten, Claire; Fromentin, Rémi; Merlini, Esther; Lawani, Mariam B.; DaFonseca, Sandrina; Bakeman, Wendy; McNulty, Amanda; Ramgopal, Moti; Michael, Nelson; Kim, Jerome H.; Ananworanich, Jintanat
2014-01-01
ABSTRACT A small pool of infected cells persists in HIV-infected individuals receiving antiretroviral therapy (ART). Here, we developed ultrasensitive assays to precisely measure the frequency of cells harboring total HIV DNA, integrated HIV DNA, and two long terminal repeat (2-LTR) circles. These assays are performed on cell lysates, which circumvents the labor-intensive step of DNA extraction, and rely on the coquantification of each HIV molecular form together with CD3 gene sequences to precisely measure cell input. Using primary isolates from HIV subtypes A, B, C, D, and CRF01_A/E, we demonstrate that these assays can efficiently quantify low target copy numbers from diverse HIV subtypes. We further used these assays to measure total HIV DNA, integrated HIV DNA, and 2-LTR circles in CD4+ T cells from HIV-infected subjects infected with subtype B. All samples obtained from ART-naive subjects were positive for the three HIV molecular forms (n = 15). Total HIV DNA, integrated HIV DNA, and 2-LTR circles were detected in, respectively, 100%, 94%, and 77% of the samples from individuals in which HIV was suppressed by ART. Higher levels of total HIV DNA and 2-LTR circles were detected in untreated subjects than individuals on ART (P = 0.0003 and P = 0.0004, respectively), while the frequency of CD4+ T cells harboring integrated HIV DNA did not differ between the two groups. These results demonstrate that these novel assays have the ability to quantify very low levels of HIV DNA of multiple HIV subtypes without the need for nucleic acid extraction, making them well suited for the monitoring of viral persistence in large populations of HIV-infected individuals. IMPORTANCE Since the discovery of viral reservoirs in HIV-infected subjects receiving suppressive ART, measuring the degree of viral persistence has been one of the greatest challenges in the field of HIV research. Here, we report the development and validation of ultrasensitive assays to measure HIV persistence in HIV-infected individuals from multiple geographical regions. These assays are relatively inexpensive, do not require DNA extraction, and can be completed in a single day. Therefore, they are perfectly adapted to monitor HIV persistence in large cohorts of HIV-infected individuals and, given their sensitivity, can be used to monitor the efficacy of therapeutic strategies aimed at interfering with HIV persistence after prolonged ART. PMID:25122785
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kang, Dongwoo; Lee, Eonseok; Choi, Young-Man
Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accuratemore » as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.« less
NASA Astrophysics Data System (ADS)
Kang, Dongwoo; duk Kim, Young; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min; Kim, Dongmin
2013-12-01
Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.
Goodworth, Adam D; Paquette, Caroline; Jones, Geoffrey Melvill; Block, Edward W; Fletcher, William A; Hu, Bin; Horak, Fay B
2012-05-01
Linear and angular control of trunk and leg motion during curvilinear navigation was investigated in subjects with cerebellar ataxia and age-matched control subjects. Subjects walked with eyes open around a 1.2-m circle. The relationship of linear to angular motion was quantified by determining the ratios of trunk linear velocity to trunk angular velocity and foot linear position to foot angular position. Errors in walking radius (the ratio of linear to angular motion) also were quantified continuously during the circular walk. Relative variability of linear and angular measures was compared using coefficients of variation (CoV). Patterns of variability were compared using power spectral analysis for the trunk and auto-covariance analysis for the feet. Errors in radius were significantly increased in patients with cerebellar damage as compared to controls. Cerebellar subjects had significantly larger CoV of feet and trunk in angular, but not linear, motion. Control subjects also showed larger CoV in angular compared to linear motion of the feet and trunk. Angular and linear components of stepping differed in that angular, but not linear, foot placement had a negative correlation from one stride to the next. Thus, walking in a circle was associated with more, and a different type of, variability in angular compared to linear motion. Results are consistent with increased difficulty of, and role of the cerebellum in, control of angular trunk and foot motion for curvilinear locomotion.
Discovery of the 198 s X-Ray Pulsar GRO J2058+42
NASA Technical Reports Server (NTRS)
Wilson, Colleen A.; Finger, Mark H.; Harmon, B. Alan; Chakrabarty, Deepto; Strohmayer, Tod
1997-01-01
GRO J2058+42, a transient 198 second x-ray pulsar, was discovered by the Burst and Transient Source Experiment (BATSE) on the Compton Gamma-Ray Observatory (CGRO), during a "giant" outburst in 1995 September-October. The total flux peaked at about 300 mCrab (20-50 keV) as measured by Earth occultation. The pulse period decreased from 198 s to 196 s during the 46-day outburst. The pulse shape evolved over the course of the outburst and exhibited energy dependent variations. BATSE observed five additional weak outbursts from GRO J2058+427 each with two week duration and peak pulsed flux of about 15 mcrab (20-50 keV), that were spaced by about 110 days. An observation of the 1996 November outburst by the Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) localized the source to within a 4' radius error circle (90% confidence) centered on R.A. = 20 h 59 m.0, Decl. = 41 deg 43 min (J2000). Additional shorter outbursts with peak pulsed fluxes of about 8 mCrab were detected by BATSE halfway between the first four 15 mCrab outbursts. The RXTE All-Sky Monitor detected 8 weak outbursts with approximately equal durations and intensities. GRO J2058+42 is most likely a Be/X-ray binary that appears to outburst at periastron and apastron. No optical counterpart has been identified to date and no x-ray source was present in the error circle in archival ROSAT observations.
Discovery of the 198 Second X-Ray Pulsar GRO J2058+42
NASA Technical Reports Server (NTRS)
Wilson, Colleen A.; Finger, Mark H.; Harmon, B. Alan; Chakrabarty, Deepto; Strohmayer, Tod
1998-01-01
GRO J2058+42, a transient 198 s X-ray pulsar, was discovered by the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory (CGRO) during a "giant" outburst in 1995 September-October. The total flux peaked at about 300 mcrab (20-50 keV) as measured by Earth occultation. The pulse period decreased from 198 to 196 s during the 46 day outburst. The pulse shape evolved over the course of the outburst and exhibited energy-dependent variations. BATSE observed five additional weak outbursts from GRO J2058 + 42, each with a 2 week duration and a peak-pulsed flux of about 15 mcrab (20-50 keV), that were spaced by about 110 days. An observation of the 1996 November outburst by the Rossi X-Ray Timing Explorer (RXTE) proportional counter array (PCA) localized the source to within a 4 s radius error circle (90% confidence) centered on R.A. = 20h 59m.0, decl. = 41 deg 43 s (J2000). Additional shorter outbursts with peak-pulsed fluxes of about 8 mcrab were detected by BATSE halfway between the first four 15 mcrab outbursts. The RXTE All-Sky Monitor detected all eight weak outbursts with approximately equal durations and intensities. GRO J2058 + 42 is most likely a Be/X-ray binary that appears to outburst at periastron and apastron, No optical counterpart has been identified to date, and no X-ray source was present in the error circle in archival ROSAT observations.
An Ultraviolet-Excess Optical Candidate for the Luminous Globular Cluster X-Ray Source in NGC 1851
NASA Technical Reports Server (NTRS)
Deutsch, Eric W.; Anderson, Scott F.; Margon, Bruce; Downes, Ronald A.
1996-01-01
The intense, bursting X-ray source in the globular cluster NGC 1851 was one of the first cluster sources discovered, but has remained optically unidentified for 25 years. We report here on results from Hubble Space Telescope WFPC2 multicolor images in NGC 1851. Our high spatial resolution images resolve approximately 200 objects in the 3 minute radius Einstein X-ray error circle, 40 times as many as in previous ground-based work. A color-magnitude diagram of the cluster clearly reveals a markedly UV-excess object with B approximately 21, (U - B) approximately -0.9, only 2 minutes from the X-ray position. The UV-excess candidate is 0.12 minutes distant from a second, unremarkable star that is 0.5 mag brighter in B; thus ground-based studies of this field are probably impractical. Three other UV-excess objects are also present among the approximately 16,000 objects in the surveyed region of the cluster, leaving an approximately 5% probability that a UV-excess object has fallen in the X-ray error circle by chance. No variability of the candidate is seen in these data, although a more complete study is required. If this object is in fact the counterpart of the X-ray source, previous inferences that some globular cluster X-ray sources are optically subluminous with respect to low-mass X-ray binaries in the field are now strengthened.
Discrepancy-based error estimates for Quasi-Monte Carlo III. Error distributions and central limits
NASA Astrophysics Data System (ADS)
Hoogland, Jiri; Kleiss, Ronald
1997-04-01
In Quasi-Monte Carlo integration, the integration error is believed to be generally smaller than in classical Monte Carlo with the same number of integration points. Using an appropriate definition of an ensemble of quasi-random point sets, we derive various results on the probability distribution of the integration error, which can be compared to the standard Central Limit Theorem for normal stochastic sampling. In many cases, a Gaussian error distribution is obtained.
Causes in the construction of causal law: A psycho-ecological model.
Young, Gerald
2010-01-01
The article presents an integrated psycho-ecological model of the construction of law, with implications for practice in law and mental health. The model is based on a series of concentric circles, each representing a layer of influence on the construction of law. The circle furthest removed from the center represents the influence of culture, society and industry, in particular, and the circle at the center of the circle represents the case at hand, for example, about individual complainant or mass action. The article begins by arguing that basic terms in relation to cause need clarification and also work is needed to disambiguate the concepts involved. After dealing with these issues, the article examines science and mental health. Is the scientific evidence presented by the expert sufficiently reliable and valid to meet admissibility standards of good compared to poor or junk science? Is the research undertaken for court or presented to court biased, with factors hidden, such as links to industry. Are individual evaluations conducted with biased science serving to justify partial conclusions? The dangers of powerful influences on the construction of law are highlighted, for example, related to the individual complainant malingering and the insurance industry protecting its financial interests at the expense of genuinely injured patients. In conclusion, suggestions for empirical research are offered. Copyright 2009 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Khajapeer, M.
1976-01-01
The interrelated nature of the problems of illiteracy, overpopulation, and poverty in developing countries is explored and an integrated approach to solving these problems in India, the Functional Literacy and Family Life Planning Education program, is described. (MS)
New Dimensions for the Multicultural Education Course
ERIC Educational Resources Information Center
Gay, Richard
2011-01-01
For the past sixteen years, the Five Dimensions of Multicultural Education, as proposed by James A. Banks (1995), have been accepted in many circles as the primary conceptual framework used in teaching multicultural education courses: content integration, the knowledge construction process, prejudice reduction, an equity pedagogy and an empowering…
Circle and Lines: Complexities of Learning in Community
ERIC Educational Resources Information Center
Schupack, Sara
2013-01-01
Following is a study that explores learning in community in a fully-integrated, team taught course at a community college in New England. These classes, Learning Communities (LCs) represent rich opportunities for exploring and practicing democratic education. From a theoretical grounding in social learning theories and an exploration into learning…
Flow tilt angles near forest edges - Part 2: Lidar anemometry
NASA Astrophysics Data System (ADS)
Dellwik, E.; Mann, J.; Bingöl, F.
2010-05-01
A novel way of estimating near-surface mean flow tilt angles from ground based Doppler lidar measurements is presented. The results are compared with traditional mast based in-situ sonic anemometry. The tilt angle assessed with the lidar is based on 10 or 30 min mean values of the velocity field from a conically scanning lidar. In this mode of measurement, the lidar beam is rotated in a circle by a prism with a fixed angle to the vertical at varying focus distances. By fitting a trigonometric function to the scans, the mean vertical velocity can be estimated. Lidar measurements from (1) a fetch-limited beech forest site taken at 48-175 m a.g.l. (above ground level), (2) a reference site in flat agricultural terrain and (3) a second reference site in complex terrain are presented. The method to derive flow tilt angles and mean vertical velocities from lidar has several advantages compared to sonic anemometry; there is no flow distortion caused by the instrument itself, there are no temperature effects and the instrument misalignment can be corrected for by assuming zero tilt angle at high altitudes. Contrary to mast-based instruments, the lidar measures the wind field with the exact same alignment error at a multitude of heights. Disadvantages with estimating vertical velocities from a lidar compared to mast-based measurements are potentially slightly increased levels of statistical errors due to limited sampling time, because the sampling is disjunct, and a requirement for homogeneous flow. The estimated mean vertical velocity is biased if the flow over the scanned circle is not homogeneous. It is demonstrated that the error on the mean vertical velocity due to flow inhomogeneity can be approximated by a function of the angle of the lidar beam to the vertical and the vertical gradient of the mean vertical velocity, whereas the error due to flow inhomogeneity on the horizontal mean wind speed is independent of the lidar beam angle. For the presented measurements over forest, it is evaluated that the systematic error due to the inhomogeneity of the flow is less than 0.2°. The results of the vertical conical scans were promising, and yielded positive flow angles for a sector where the forest is fetch-limited. However, more data and analysis are needed for a complete evaluation of the lidar technique.
NASA Astrophysics Data System (ADS)
Zhang, Yunju; Chen, Zhongyi; Guo, Ming; Lin, Shunsheng; Yan, Yinyang
2018-01-01
With the large capacity of the power system, the development trend of the large unit and the high voltage, the scheduling operation is becoming more frequent and complicated, and the probability of operation error increases. This paper aims at the problem of the lack of anti-error function, single scheduling function and low working efficiency for technical support system in regional regulation and integration, the integrated construction of the error prevention of the integrated architecture of the system of dispatching anti - error of dispatching anti - error of power network based on cloud computing has been proposed. Integrated system of error prevention of Energy Management System, EMS, and Operation Management System, OMS have been constructed either. The system architecture has good scalability and adaptability, which can improve the computational efficiency, reduce the cost of system operation and maintenance, enhance the ability of regional regulation and anti-error checking with broad development prospects.
NASA Astrophysics Data System (ADS)
Bressloff, P. C.; Bressloff, N. W.
2000-02-01
Orientation tuning in a ring of pulse-coupled integrate-and-fire (IF) neurons is analyzed in terms of spontaneous pattern formation. It is shown how the ring bifurcates from a synchronous state to a non-phase-locked state whose spike trains are characterized by quasiperiodic variations of the inter-spike intervals (ISIs) on closed invariant circles. The separation of these invariant circles in phase space results in a localized peak of activity as measured by the time-averaged firing rate of the neurons. This generates a sharp orientation tuning curve that can lock to a slowly rotating, weakly tuned external stimulus. For fast synapses, breakup of the quasiperiodic orbits occurs leading to high spike time variability suggestive of chaos.
Murray, John M; McBride, Kristin; Boesecke, Christoph; Bailey, Michelle; Amin, Janaki; Suzuki, Kazuo; Baker, David; Zaunders, John J; Emery, Sean; Cooper, David A; Koelsch, Kersten K; Kelleher, Anthony D
2012-03-13
We investigated the dynamics of HIV RNA and HIV DNA levels after the commencement of raltegravir-based antiretroviral therapy (ART) in primary (PHI) and chronically HIV-infected (CHI) individuals (the PINT study). We recruited 8 PHI and 8 CHI ART-naive individuals who commenced a 1-year combination regimen of Truvada and the integrase inhibitor raltegravir. Nonlinear mixed effects modelling was used to determine multiphasic decay of plasma HIV RNA levels (pVL), as well as dynamics of total, episomal [2-long terminal repeats (LTR)] and integrated HIV DNA in CD4 T cells from peripheral blood. Although pVL decreased faster through first and second phase for PHI individuals there was no difference in the final level reaching a mean of 9 copies/ml by week 16 that was maintained thereafter. Total HIV DNA and integrated HIV DNA levels from CHI patients were significantly higher than from PHI patients. However, at no time did 2-LTR levels differ between groups. Of note, 2-LTR circles exhibited an initial increase peaking at week 3 followed by biphasic decay with a half-life of 29 days. Second phase integrated HIV DNA levels were significantly correlated with duration of infection and consistent with this form of infection occurring at approximately 100 000 integration events per day in the absence of ART, achieving its 50% level 2 years after infection. Integrated HIV DNA levels accumulate with duration of untreated HIV infection. The relatively short half-life and high levels of 2-LTR circles after 1 year support continued HIV transmission during ART.
Cheng, Ching-Min; Hwang, Sheue-Ling
2015-03-01
This paper outlines the human error identification (HEI) techniques that currently exist to assess latent human errors. Many formal error identification techniques have existed for years, but few have been validated to cover latent human error analysis in different domains. This study considers many possible error modes and influential factors, including external error modes, internal error modes, psychological error mechanisms, and performance shaping factors, and integrates several execution procedures and frameworks of HEI techniques. The case study in this research was the operational process of changing chemical cylinders in a factory. In addition, the integrated HEI method was used to assess the operational processes and the system's reliability. It was concluded that the integrated method is a valuable aid to develop much safer operational processes and can be used to predict human error rates on critical tasks in the plant. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Error detection and reduction in blood banking.
Motschman, T L; Moore, S B
1996-12-01
Error management plays a major role in facility process improvement efforts. By detecting and reducing errors, quality and, therefore, patient care improve. It begins with a strong organizational foundation of management attitude with clear, consistent employee direction and appropriate physical facilities. Clearly defined critical processes, critical activities, and SOPs act as the framework for operations as well as active quality monitoring. To assure that personnel can detect an report errors they must be trained in both operational duties and error management practices. Use of simulated/intentional errors and incorporation of error detection into competency assessment keeps employees practiced, confident, and diminishes fear of the unknown. Personnel can clearly see that errors are indeed used as opportunities for process improvement and not for punishment. The facility must have a clearly defined and consistently used definition for reportable errors. Reportable errors should include those errors with potentially harmful outcomes as well as those errors that are "upstream," and thus further away from the outcome. A well-written error report consists of who, what, when, where, why/how, and follow-up to the error. Before correction can occur, an investigation to determine the underlying cause of the error should be undertaken. Obviously, the best corrective action is prevention. Correction can occur at five different levels; however, only three of these levels are directed at prevention. Prevention requires a method to collect and analyze data concerning errors. In the authors' facility a functional error classification method and a quality system-based classification have been useful. An active method to search for problems uncovers them further upstream, before they can have disastrous outcomes. In the continual quest for improving processes, an error management program is itself a process that needs improvement, and we must strive to always close the circle of quality assurance. Ultimately, the goal of better patient care will be the reward.
Observations of the Star Cor Caroli at the Apple Valley Workshop 2016 (Abstract)
NASA Astrophysics Data System (ADS)
Estrada, R.; Boyd, S.; Estrada, C.; Evans, C.; Rhoades, H.; Rhoades, M.; Rhoades, T.
2017-12-01
(Abstract only) Using a 22-inch Newtonian Alt/Az telescope and Celestron Micro Guide eyepiece, students participating in a workshop observed the binary star Cor Caroli (STF 1692; alpha CVn) and found a position angle of 231.0 degrees as well as an average separation of 18.7" This observation compared favorably with the 2015 Washington Double Star published position. This project was part of Mark Brewer's Apple Valley Double Star Workshop. The results were analyzed using bias and circle error probability calculations.
NASA Astrophysics Data System (ADS)
Cheung, C. C.
2008-06-01
The AGILE team (Chen et al. ATel #1585) has detected a new flare (occurring on June 20/21, 2008) from AGL2021+4029, the variable gamma-ray source in the Cygnus region. The error circles of this new June flare and that of the newly reported position of the persistent source, both unfortunately, lie outside of the r~0.5 deg field we targeted with the VLA (ATel #1584) following the May 2008 rebrightening (Giuliani et al.
Diagnostic accuracy of MRI in the measurement of glenoid bone loss.
Gyftopoulos, Soterios; Hasan, Saqib; Bencardino, Jenny; Mayo, Jason; Nayyar, Samir; Babb, James; Jazrawi, Laith
2012-10-01
The purpose of this study is to assess the accuracy of MRI quantification of glenoid bone loss and to compare the diagnostic accuracy of MRI to CT in the measurement of glenoid bone loss. MRI, CT, and 3D CT examinations of 18 cadaveric glenoids were obtained after the creation of defects along the anterior and anteroinferior glenoid. The defects were measured by three readers separately and blindly using the circle method. These measurements were compared with measurements made on digital photographic images of the cadaveric glenoids. Paired sample Student t tests were used to compare the imaging modalities. Concordance correlation coefficients were also calculated to measure interobserver agreement. Our data show that MRI could be used to accurately measure glenoid bone loss with a small margin of error (mean, 3.44%; range, 2.06-5.94%) in estimated percentage loss. MRI accuracy was similar to that of both CT and 3D CT for glenoid loss measurements in our study for the readers familiar with the circle method, with 1.3% as the maximum expected difference in accuracy of the percentage bone loss between the different modalities (95% confidence). Glenoid bone loss can be accurately measured on MRI using the circle method. The MRI quantification of glenoid bone loss compares favorably to measurements obtained using 3D CT and CT. The accuracy of the measurements correlates with the level of training, and a learning curve is expected before mastering this technique.
Hybrid Transverse Polar Navigation for High-Precision and Long-Term INSs
Wu, Qiuping; Zhang, Rong; Hu, Peida; Li, Haixia
2018-01-01
Transverse navigation has been proposed to help inertial navigation systems (INSs) fill the gap of polar navigation ability. However, as the transverse system does not have the ability of navigate globally, a complicated switch between the transverse and the traditional algorithms is necessary when the system moves across the polar circles. To maintain the inner continuity and consistency of the core algorithm, a hybrid transverse polar navigation is proposed in this research based on a combination of Earth-fixed-frame mechanization and transverse-frame outputs. Furthermore, a thorough analysis of kinematic error characteristics, proper damping technology and corresponding long-term contributions of main error sources is conducted for the high-precision INSs. According to the analytical expressions of the long-term navigation errors in polar areas, the 24-h period symmetrical oscillation with a slowly divergent amplitude dominates the transverse horizontal position errors, and the first-order drift dominates the transverse azimuth error, which results from the g0 gyro drift coefficients that occur in corresponding directions. Simulations are conducted to validate the theoretical analysis and the deduced analytical expressions. The results show that the proposed hybrid transverse navigation can ensure the same accuracy and oscillation characteristics in polar areas as the traditional algorithm in low and mid latitude regions. PMID:29757242
Hybrid Transverse Polar Navigation for High-Precision and Long-Term INSs.
Wu, Ruonan; Wu, Qiuping; Han, Fengtian; Zhang, Rong; Hu, Peida; Li, Haixia
2018-05-12
Transverse navigation has been proposed to help inertial navigation systems (INSs) fill the gap of polar navigation ability. However, as the transverse system does not have the ability of navigate globally, a complicated switch between the transverse and the traditional algorithms is necessary when the system moves across the polar circles. To maintain the inner continuity and consistency of the core algorithm, a hybrid transverse polar navigation is proposed in this research based on a combination of Earth-fixed-frame mechanization and transverse-frame outputs. Furthermore, a thorough analysis of kinematic error characteristics, proper damping technology and corresponding long-term contributions of main error sources is conducted for the high-precision INSs. According to the analytical expressions of the long-term navigation errors in polar areas, the 24-h period symmetrical oscillation with a slowly divergent amplitude dominates the transverse horizontal position errors, and the first-order drift dominates the transverse azimuth error, which results from the gyro drift coefficients that occur in corresponding directions. Simulations are conducted to validate the theoretical analysis and the deduced analytical expressions. The results show that the proposed hybrid transverse navigation can ensure the same accuracy and oscillation characteristics in polar areas as the traditional algorithm in low and mid latitude regions.
NASA Astrophysics Data System (ADS)
Lu, Xiaojun; Liu, Changli; Chen, Lei
2018-04-01
In this paper, a redundant Piezo-driven stage having 3RRR compliant mechanism is introduced, we propose the master-slave control with trajectory planning (MSCTP) strategy and Bouc-Wen model to improve its micro-motion tracking performance. The advantage of the proposed controller lies in that its implementation only requires a simple control strategy without the complexity of modeling to avoid the master PEA's tracking error. The dynamic model of slave PEA system with Bouc-Wen hysteresis is established and identified via particle swarm optimization (PSO) approach. The Piezo-driven stage with operating period T=1s and 2s is implemented to track a prescribed circle. The simulation results show that MSCTP with Bouc-Wen model reduces the trajectory tracking errors to the range of the accuracy of our available measurement.
A method of detection to the grinding wheel layer thickness based on computer vision
NASA Astrophysics Data System (ADS)
Ji, Yuchen; Fu, Luhua; Yang, Dujuan; Wang, Lei; Liu, Changjie; Wang, Zhong
2018-01-01
This paper proposed a method of detection to the grinding wheel layer thickness based on computer vision. A camera is used to capture images of grinding wheel layer on the whole circle. Forward lighting and back lighting are used to enables a clear image to be acquired. Image processing is then executed on the images captured, which consists of image preprocessing, binarization and subpixel subdivision. The aim of binarization is to help the location of a chord and the corresponding ring width. After subpixel subdivision, the thickness of the grinding layer can be calculated finally. Compared with methods usually used to detect grinding wheel wear, method in this paper can directly and quickly get the information of thickness. Also, the eccentric error and the error of pixel equivalent are discussed in this paper.
Metacognition and proofreading: the roles of aging, motivation, and interest.
Hargis, Mary B; Yue, Carole L; Kerr, Tyson; Ikeda, Kenji; Murayama, Kou; Castel, Alan D
2017-03-01
The current study examined younger and older adults' error detection accuracy, prediction calibration, and postdiction calibration on a proofreading task, to determine if age-related differences would be present in this type of common error detection task. Participants were given text passages, and were first asked to predict the percentage of errors they would detect in the passage. They then read the passage and circled errors (which varied in complexity and locality), and made postdictions regarding their performance, before repeating this with another passage and answering a comprehension test of both passages. There were no age-related differences in error detection accuracy, text comprehension, or metacognitive calibration, though participants in both age groups were overconfident overall in their metacognitive judgments. Both groups gave similar ratings of motivation to complete the task. The older adults rated the passages as more interesting than younger adults did, although this level of interest did not appear to influence error-detection performance. The age equivalence in both proofreading ability and calibration suggests that the ability to proofread text passages and the associated metacognitive monitoring used in judging one's own performance are maintained in aging. These age-related similarities persisted when younger adults completed the proofreading tasks on a computer screen, rather than with paper and pencil. The findings provide novel insights regarding the influence that cognitive aging may have on metacognitive accuracy and text processing in an everyday task.
Experiments Testing the Causes of Namibian Fairy Circles.
Tschinkel, Walter R
2015-01-01
The grasslands on the sandy soils of the eastern edge of the Namib Desert of Namibia are strikingly punctuated by millions of mostly regularly-spaced circular bare spots 2 to 10 m or more in diameter, generally with a margin of taller grasses. The causes of these so called fairy circles are unknown, but several hypotheses have been advanced. In October 2009, we set up experiments that specifically tested four hypothesized causes, and monitored these 5 times between 2009 and 2015. Grass exclusion in circles due to seepage of subterranean vapors or gases was tested by burying an impermeable barrier beneath fairy circles, but seedling density and growth did not differ from barrier-less controls. Plant germination and growth inhibition by allelochemicals or nutrient deficiencies in fairy circle soils were tested by transferring fairy circle soil to artificially cleared circles in the grassy matrix, and matrix soil to fairy circles (along with circle to circle and matrix to matrix controls). None of the transfers changed the seedling density and growth from the control reference conditions. Limitation of plant growth due to micronutrient depletion within fairy circles was tested by supplementing circles with a micronutrient mixture, but did not result in differences in plant seedling density and growth. Short-range vegetation competitive feedbacks were tested by creating artificially-cleared circles of 2 or 4 m diameter located 2 or 6 m from a natural fairy circle. The natural circles remained bare and the artificial circles revegetated. These four experiments provided evidence that fairy circles were not caused by subterranean vapors, that fairy circle soil per se did not inhibit plant growth, and that the circles were not caused by micronutrient deficiency. There was also no evidence that vegetative feedbacks affected fairy circles on a 2 to 10 m scale. Landscape-scale vegetative self-organization is discussed as a more likely cause of fairy circles.
Usta, Taner A; Ozkaynak, Aysel; Kovalak, Ebru; Ergul, Erdinc; Naki, M Murat; Kaya, Erdal
2015-08-01
Two-dimensional (2D) view is known to cause practical difficulties for surgeons in conventional laparoscopy. Our goal was to evaluate whether the new-generation, Three-Dimensional Laparoscopic Vision System (3D LVS) provides greater benefit in terms of execution time and error number during the performance of surgical tasks. This study tests the hypothesis that the use of the new generation 3D LVS can significantly improve technical ability on complex laparoscopic tasks in an experimental model. Twenty-four participants (8 experienced, 8 minimally experienced, and 8 inexperienced) were evaluated for 10 different tasks in terms of total execution time and error number. The 4-point lickert scale was used for subjective assessment of the two imaging modalities. All tasks were completed by all participants. Statistically significant difference was determined between 3D and 2D systems in the tasks of bead transfer and drop, suturing, and pick-and-place in the inexperienced group; in the task of passing through two circles with the needle in the minimally experienced group; and in the tasks of bead transfer and drop, suturing and passing through two circles with the needle in the experienced group. Three-dimensional imaging was preferred over 2D in 6 of the 10 subjective criteria questions on 4-point lickert scale. The majority of the tasks were completed in a shorter time using 3D LVS compared to 2D LVS. The subjective Likert-scale ratings from each group also demonstrated a clear preference for 3D LVS. New 3D LVS has the potential to improve the learning curve, and reduce the operating time and error rate during the performances of laparoscopic surgeons. Our results suggest that the new-generation 3D HD LVS will be helpful for surgeons in laparoscopy (Clinical Trial ID: NCT01799577, Protocol ID: BEHGynobs-4).
Keeping it simple: studying grammatical encoding with lexically reduced item sets
Veenstra, Alma; Acheson, Daniel J.; Meyer, Antje S.
2014-01-01
Compared to the large body of work on lexical access, little research has been done on grammatical encoding in language production. An exception is the generation of subject-verb agreement. Here, two key findings have been reported: (1) speakers make more agreement errors when the head and local noun of a phrase mismatch in number than when they match [e.g., the key to the cabinet(s)]; and (2) this attraction effect is asymmetric, with stronger attraction for singular than for plural head nouns. Although these findings are robust, the cognitive processes leading to agreement errors and their significance for the generation of correct agreement are not fully understood. We propose that future studies of agreement, and grammatical encoding in general, may benefit from using paradigms that tightly control the variability of the lexical content of the material. We report two experiments illustrating this approach. In both of them, the experimental items featured combinations of four nouns, four color adjectives, and two prepositions. In Experiment 1, native speakers of Dutch described pictures in sentences such as the circle next to the stars is blue. In Experiment 2, they carried out a forced-choice task, where they read subject noun phrases (e.g., the circle next to the stars) and selected the correct verb-phrase (is blue or are blue) with a button press. Both experiments showed an attraction effect, with more errors after subject phrases with mismatching, compared to matching head and local nouns. This effect was stronger for singular than plural heads, replicating the attraction asymmetry. In contrast, the response times recorded in Experiment 2 showed similar attraction effects for singular and plural head nouns. These results demonstrate that critical agreement phenomena can be elicited reliably in lexically reduced contexts. We discuss the theoretical implications of the findings and the potential and limitations of studies using lexically simple materials. PMID:25101039
Keeping it simple: studying grammatical encoding with lexically reduced item sets.
Veenstra, Alma; Acheson, Daniel J; Meyer, Antje S
2014-01-01
Compared to the large body of work on lexical access, little research has been done on grammatical encoding in language production. An exception is the generation of subject-verb agreement. Here, two key findings have been reported: (1) speakers make more agreement errors when the head and local noun of a phrase mismatch in number than when they match [e.g., the key to the cabinet(s)]; and (2) this attraction effect is asymmetric, with stronger attraction for singular than for plural head nouns. Although these findings are robust, the cognitive processes leading to agreement errors and their significance for the generation of correct agreement are not fully understood. We propose that future studies of agreement, and grammatical encoding in general, may benefit from using paradigms that tightly control the variability of the lexical content of the material. We report two experiments illustrating this approach. In both of them, the experimental items featured combinations of four nouns, four color adjectives, and two prepositions. In Experiment 1, native speakers of Dutch described pictures in sentences such as the circle next to the stars is blue. In Experiment 2, they carried out a forced-choice task, where they read subject noun phrases (e.g., the circle next to the stars) and selected the correct verb-phrase (is blue or are blue) with a button press. Both experiments showed an attraction effect, with more errors after subject phrases with mismatching, compared to matching head and local nouns. This effect was stronger for singular than plural heads, replicating the attraction asymmetry. In contrast, the response times recorded in Experiment 2 showed similar attraction effects for singular and plural head nouns. These results demonstrate that critical agreement phenomena can be elicited reliably in lexically reduced contexts. We discuss the theoretical implications of the findings and the potential and limitations of studies using lexically simple materials.
Study of Current Measurement Method Based on Circular Magnetic Field Sensing Array
Li, Zhenhua; Zhang, Siqiu; Wu, Zhengtian; Tao, Yuan
2018-01-01
Classic core-based instrument transformers are more prone to magnetic saturation. This affects the measurement accuracy of such transformers and limits their applications in measuring large direct current (DC). Moreover, protection and control systems may exhibit malfunctions due to such measurement errors. This paper presents a more accurate method for current measurement based on a circular magnetic field sensing array. The proposed measurement approach utilizes multiple hall sensors that are evenly distributed on a circle. The average value of all hall sensors is regarded as the final measurement. The calculation model is established in the case of magnetic field interference of the parallel wire, and the simulation results show that the error decreases significantly when the number of hall sensors n is greater than 8. The measurement error is less than 0.06% when the wire spacing is greater than 2.5 times the radius of the sensor array. A simulation study on the off-center primary conductor is conducted, and a kind of hall sensor compensation method is adopted to improve the accuracy. The simulation and test results indicate that the measurement error of the system is less than 0.1%. PMID:29734742
Study of Current Measurement Method Based on Circular Magnetic Field Sensing Array.
Li, Zhenhua; Zhang, Siqiu; Wu, Zhengtian; Abu-Siada, Ahmed; Tao, Yuan
2018-05-05
Classic core-based instrument transformers are more prone to magnetic saturation. This affects the measurement accuracy of such transformers and limits their applications in measuring large direct current (DC). Moreover, protection and control systems may exhibit malfunctions due to such measurement errors. This paper presents a more accurate method for current measurement based on a circular magnetic field sensing array. The proposed measurement approach utilizes multiple hall sensors that are evenly distributed on a circle. The average value of all hall sensors is regarded as the final measurement. The calculation model is established in the case of magnetic field interference of the parallel wire, and the simulation results show that the error decreases significantly when the number of hall sensors n is greater than 8. The measurement error is less than 0.06% when the wire spacing is greater than 2.5 times the radius of the sensor array. A simulation study on the off-center primary conductor is conducted, and a kind of hall sensor compensation method is adopted to improve the accuracy. The simulation and test results indicate that the measurement error of the system is less than 0.1%.
NASA Astrophysics Data System (ADS)
Zhang, Chupeng; Zhao, Huiying; Zhu, Xueliang; Zhao, Shijie; Jiang, Chunye
2018-01-01
The chemical mechanical polishing (CMP) is a key process during the machining route of plane optics. To improve the polishing efficiency and accuracy, a CMP model and machine tool were developed. Based on the Preston equation and the axial run-out error measurement results of the m circles on the tin plate, a CMP model that could simulate the material removal at any point on the workpiece was presented. An analysis of the model indicated that lower axial run-out error led to lower material removal but better polishing efficiency and accuracy. Based on this conclusion, the CMP machine was designed, and the ultraprecision gas hydrostatic guideway and rotary table as well as the Siemens 840Dsl numerical control system were incorporated in the CMP machine. To verify the design principles of machine, a series of detection and machining experiments were conducted. The LK-G5000 laser sensor was employed for detecting the straightness error of the gas hydrostatic guideway and the axial run-out error of the gas hydrostatic rotary table. A 300-mm-diameter optic was chosen for the surface profile machining experiments performed to determine the CMP efficiency and accuracy.
Literacy, Self-esteem and Locus of Control
ERIC Educational Resources Information Center
Galbraith, Alison; Alexander, Joy
2005-01-01
In this article, Alison Galbraith and Joy Alexander use case studies of a group of primary school pupils to examine the efficacy of an integrated, eclectic approach to the teaching of literacy, including whether constructs such as self-concept and self-esteem have a bearing on academic achievement. Circle Time activities, interactive teaching…
ERIC Educational Resources Information Center
Keating, Avril; Ortloff, Debora Hinderliter; Philippou, Stavroula
2009-01-01
Citizenship education has been the subject of growing attention in policy and academic circles over the past 20 years. Citizenship education curricula have typically focused on national institutions, issues, and ties. Citizenship education has been closely bound up with the legitimacy of the nation-state, and alternative institutions and…
Integration of wireless sensor networks into automatic irrigation scheduling of a center pivot
USDA-ARS?s Scientific Manuscript database
A six-span center pivot system was used as a platform for testing two wireless sensor networks (WSN) of infrared thermometers. The cropped field was a semi-circle, divided into six pie shaped sections of which three were irrigated manually and three were irrigated automatically based on the time tem...
Effectiveness of Using GeoGebra on Students' Understanding in Learning Circles
ERIC Educational Resources Information Center
Shadaan, Praveen; Leong, Kwan Eu
2013-01-01
The use of technology in the pedagogical process is growing at a phenomenal rate due to the vast availability of gadgets. As a result, educationists see the urgent need for integrating technology in students' mathematical activities. Therefore, the purpose of this quasi experimental study was to investigate students' understanding in learning…
LEDGF/p75 Deficiency Increases Deletions at the HIV-1 cDNA Ends.
Bueno, Murilo T D; Reyes, Daniel; Llano, Manuel
2017-09-15
Processing of unintegrated linear HIV-1 cDNA by the host DNA repair system results in its degradation and/or circularization. As a consequence, deficient viral cDNA integration generally leads to an increase in the levels of HIV-1 cDNA circles containing one or two long terminal repeats (LTRs). Intriguingly, impaired HIV-1 integration in LEDGF/p75-deficient cells does not result in a correspondent increase in viral cDNA circles. We postulate that increased degradation of unintegrated linear viral cDNA in cells lacking the lens epithelium-derived growth factor (LEDGF/p75) account for this inconsistency. To evaluate this hypothesis, we characterized the nucleotide sequence spanning 2-LTR junctions isolated from LEDGF/p75-deficient and control cells. LEDGF/p75 deficiency resulted in a significant increase in the frequency of 2-LTRs harboring large deletions. Of note, these deletions were dependent on the 3' processing activity of integrase and were not originated by aberrant reverse transcription. Our findings suggest a novel role of LEDGF/p75 in protecting the unintegrated 3' processed linear HIV-1 cDNA from exonucleolytic degradation.
Conducting effective performance appraisals.
2001-01-01
According to experts, performance appraisals rate just below firing someone as the least favorite thing managers do. Many factors contribute to this view--one is that current systems do a poor job of evaluating performance and in fact often impede both evaluation and performance. When used as part of an ongoing supportive process of goal setting and feedback, performance appraisals can enhance performance and morale. One alternative to traditional employee evaluation methods is full-circle or 360-degree feedback. Contained in this issue are practical suggestions for preparing employees for performance appraisals which, when followed daily, encourage employees to put their best feet forward as part of their regular routine. Also included is a template specific to assessing the performance of clinical laboratory technologists . Additionally, numerous resources are provided to help you refine appraisal systems to fit your needs. Full-circle feedback is proving to be a boon to managers. It relieves them from being the exclusive "heavies" in evaluating performance, integrates appraisal input from several sources, and incorporates increasing employee skills, competencies, and satisfaction, thus improving productivity of people and processes. And aren't integration and continuous improvement what the laboratory is all about?
Huber, J F; Hüsler, J; Zumstein, M D; Ruflin, G; Lüscher, M
2007-01-01
The visual analogue scale (VAS) and Likert scale (LS) are widely used but the patients might have difficulties to work with these scales and there might be errors in calculation. The visual circle scale (VCS) is a graphic construct with a simple grading to augment the understanding and ease for calculation. This study compares the different scales in orthopaedic patients for pain assessment postoperatively. In addition, the scales were rated by the patients for simplicity, understanding and global rating. Included were 65 patients (40 women) with an average age of 66 years with 330 pain assessments and 65 questionnaire ratings. The average pain was LS 42.7, VAS 39.3, VCS 44. The correlation coefficients r (Spearman) between all scales were > 0.89 and the same held also for sensitivity for change. The VCS was the scale preferred by > 50 % of the orthopaedic patients to assess the pain. The VCS is able to measure pain comparably to the known scales (VAS, Likert scale). From the patients point of view it is the preferred scale to work with.
Ghassibi, Mark P; Chien, Jason L; Patthanathamrongkasem, Thipnapa; Abumasmah, Ramiz K; Rosman, Michael S; Skaat, Alon; Tello, Celso; Liebmann, Jeffrey M; Ritch, Robert; Park, Sung Chul
2017-04-01
To compare varying circumpapillary optical coherence tomographic (OCT) scan diameters for glaucoma diagnosis. Prospective, cross-sectional, observational study. Circumpapillary retinal nerve fiber layer thickness (RNFLT) was measured using spectral-domain OCT in 1 randomly selected eye. Scans with diameters of 3.5, 4.1, and 4.7 mm were obtained, each with 7 parameters: mean global (G) RNFLT and mean RNFLT for the temporal-inferior (TI), nasal-inferior (NI), temporal-superior (TS), nasal-superior (NS), nasal (N), and temporal (T) sectors. Areas under the receiver operating characteristic curve (AUCs) were calculated. Mean age was 55±18 years in 68 healthy eyes and 59±15 years in 95 glaucomatous eyes (P=0.12). Visual field mean deviation was -7.55±6.61 dB in glaucomatous eyes. In all 3 circle scans, mean TI RNFLT had the greatest AUC (0.974 to 0.983), followed by mean G RNFLT (0.949 to 0.956). The AUC of mean TI RNFLT in the 4.1-mm scan (0.983) was greater than the AUCs of mean TI RNFLTs in the 4.7- (0.978; P=0.128) and 3.5-mm (0.974; P=0.049) scans. The AUC of mean TI RNFLT in the 4.1-mm scan (0.983) was greater than the AUCs of mean G RNFLTs in the 3.5- (0.954; P=0.011), 4.1- (0.956; P=0.016), and 4.7-mm (0.949; P=0.011) scans. In 2 eyes with large parapapillary atrophy, RNFL segmentation error was noted only in the 3.5-mm scan in the area of parapapillary atrophy. Further investigations to find the spectral-domain OCT circle scan diameter with the best diagnostic capability and the least artifacts are warranted, especially focusing on larger-than-conventional circle scans.
Training Performance of Laparoscopic Surgery in Two- and Three-Dimensional Displays.
Lin, Chiuhsiang Joe; Cheng, Chih-Feng; Chen, Hung-Jen; Wu, Kuan-Ying
2017-04-01
This research investigated differences in the effects of a state-of-art stereoscopic 3-dimensional (3D) display and a traditional 2-dimensional (2D) display in simulated laparoscopic surgery over a longer duration than in previous publications and studied the learning effects of the 2 display systems on novices. A randomized experiment with 2 factors, image dimensions and image sequence, was conducted to investigate differences in the mean movement time, the mean error frequency, NASA-TLX cognitive workload, and visual fatigue in pegboard and circle-tracing tasks. The stereoscopic 3D display had advantages in mean movement time ( P < .001 and P = .002) and mean error frequency ( P = .010 and P = .008) in both the tasks. There were no significant differences in the objective visual fatigue ( P = .729 and P = .422) and in the NASA-TLX ( P = .605 and P = .937) cognitive workload between the 3D and the 2D displays on both the tasks. For the learning effect, participants who used the stereoscopic 3D display first had shorter mean movement time in the 2D display environment on both the pegboard ( P = .011) and the circle-tracing ( P = .017) tasks. The results of this research suggest that a stereoscopic system would not result in higher objective visual fatigue and cognitive workload than a 2D system, and it might reduce the performance time and increase the precision of surgical operations. In addition, learning efficiency of the stereoscopic system on the novices in this study demonstrated its value for training and education in laparoscopic surgery.
Trajectory Specification for High-Capacity Air Traffic Control
NASA Technical Reports Server (NTRS)
Paielli, Russell A.
2004-01-01
In the current air traffic management system, the fundamental limitation on airspace capacity is the cognitive ability of human air traffic controllers to maintain safe separation with high reliability. The doubling or tripling of airspace capacity that will be needed over the next couple of decades will require that tactical separation be at least partially automated. Standardized conflict-free four-dimensional trajectory assignment will be needed to accomplish that objective. A trajectory specification format based on the Extensible Markup Language is proposed for that purpose. This format can be used to downlink a trajectory request, which can then be checked on the ground for conflicts and approved or modified, if necessary, then uplinked as the assigned trajectory. The horizontal path is specified as a series of geodetic waypoints connected by great circles, and the great-circle segments are connected by turns of specified radius. Vertical profiles for climb and descent are specified as low-order polynomial functions of along-track position, which is itself specified as a function of time. Flight technical error tolerances in the along-track, cross-track, and vertical axes define a bounding space around the reference trajectory, and conformance will guarantee the required separation for a period of time known as the conflict time horizon. An important safety benefit of this regimen is that the traffic will be able to fly free of conflicts for at least several minutes even if all ground systems and the entire communication infrastructure fail. Periodic updates in the along-track axis will adjust for errors in the predicted along-track winds.
Aerodynamic loads on a Darrieus rotor blade
NASA Astrophysics Data System (ADS)
Wilson, R. E.; McKie, W. R.; Lissaman, P. B. S.; James, M.
1983-03-01
A method is presented for the free vortex analysis of a Darrieus rotor blade in nonsteady motion, which employs the circle theorem to map the moving rotor airfoil into the circle plane and models the wake generated in terms of point vortices. Nascent vortex strength and position are taken from the Kutta condition, so that the nascent vortex has the same strength as a vortex sheet of uniform strength. Pressure integration over the plate and wake vortex impulse methods yields the same numerical results. The numerical results presented for a one-bladed Darrieus rotor at a tip/speed ratio of three, and two different chord sizes, indicate that the moment on the blade can be adequately approximated by quasi-steady relationships, although the accurate determination of local velocity and circulation are still required.
Security analysis of cyber-physical system
NASA Astrophysics Data System (ADS)
Li, Bo; Zhang, Lichen
2017-05-01
In recent years, Cyber-Physical System (CPS) has become an important research direction of academic circles and scientific and technological circles at home and abroad, is considered to be following the third wave of world information technology after the computer, the Internet. PS is a multi-dimensional, heterogeneous, deep integration of open systems, Involving the computer, communication, control and other disciplines of knowledge. As the various disciplines in the research theory and methods are significantly different, so the application of CPS has brought great challenges. This paper introduces the definition and characteristics of CPS, analyzes the current situation of CPS, analyzes the security threats faced by CPS, and gives the security solution for security threats. It also discusses CPS-specific security technology, to promote the healthy development of CPS in information security.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, T; Ding, H; Lipinski, J
2015-06-15
Purpose: To develop a physics-based model for accurate quantification of the cross-sectional area (CSA) of coronary arteries in CT angiography by measuring the integrated density to account for the partial volume effect. Methods: In this technique the integrated density of the object as compared with its local background is measured to account for the partial volume effect. Normal vessels were simulated as circles with diameters in the range of 0.1–3mm. Diseased vessels were simulated as 2, 3, and 4mm diameter vessels with 10–90% area stenosis, created by inserting circular plaques. A simplified two material model was used with the lumenmore » as 8mg/ml Iodine and background as lipid. The contrast-to-noise ratio between lumen and background was approximately 26. Linear fits to the known CSA were calculated. The precision and accuracy of the measurement were quantified using the root-mean-square fit deviations (RMSD) and errors to the known CSA (RMSE). Results compared to manual segmentation of the vessel lumen. To assess the impact of random variations, coefficients of variation (CV) from 10 simulations for each vessel were computed to determine reliability. Measurements with CVs less than 10% were considered reliable. Results: For normal vessels, the precision and accuracy of the integrated density technique were 0.12mm{sup 2} and 0.28mm{sup 2}, respectively. The corresponding results for manual segmentation were 0.27mm{sup 2} and 0.43mm{sup 2}. For diseased vessels, the precision and accuracy of the integrated density technique were 0.14mm{sup 2} and 0.19mm{sup 2}. Corresponding results for manual segmentation were 0.42mm{sup 2} and 0.71mm{sup 2}. Reliable CSAs were obtained for normal vessels with diameters larger than 1 mm and for diseased vessels with area as low as 1.26mm2. Conclusion: The CSA based on integrated density showed improved precision and accuracy as compared with manual segmentation in simulation. These results indicate the potential of using integrated density to quantify CSA of coronary arteries in CT angiography.« less
Enhancing Conceptual Understanding of Trigonometry Using Earth Geometry and the Great Circle
ERIC Educational Resources Information Center
Wongapiwatkul, Pimpalak; Laosinchai, Parames; Panijpan, Bhinyo
2011-01-01
Trigonometry is an integral part of the draft for the Senior Secondary Australian National Curriculum for Mathematics, as it is a topic in Unit 2 of both Specialist Mathematics and Mathematics Methods, and a reviewing topic in Unit 1, Topic 3: Measurement and Geometry of General Mathematics. However, learning trigonometric ideas is difficult for…
Integrating Group-Self Evaluation in Open and Distance Learning System
ERIC Educational Resources Information Center
Osuji, U. S. Ajunwa
2010-01-01
Every instructional process involves a strategic assessment system for a complete teaching leaning circle. Any assessment system which is seriously flawed, should call for a change, a rethink or a repackaging for sustainability, and to be a part of teaching and learning. Assessment should be meaningful to both the assessors and the assessees. The…
Universities and Sustainable Development: The Necessity for Barriers to Change
ERIC Educational Resources Information Center
Scott, William; Gough, Stephen
2007-01-01
Over the last thirty years, the idea of sustainable development has come to be seen in policy circles across the globe as a necessary and urgent response to a range of social and environmental issues that threaten both the integrity of the biosphere, and human wellbeing. Increasingly, education, and particularly higher education, is seen to have a…
The Role of Civic Skills in Fostering Civic Engagement. CIRCLE Working Paper 06
ERIC Educational Resources Information Center
Kirlin, Mary
2003-01-01
The idea of a set of skills, usually called civic skills, which are required to effectively participate in civic and political life, is integral to many concepts of political participation. This literature search is designed to investigate what is known about civic skills empirically and theoretically including how they are defined and measured,…
ERIC Educational Resources Information Center
Newcomer, Kathryn; Brass, Clinton T.
2016-01-01
The "performance movement" has been a subject of enthusiasm and frustration for evaluators. Performance measurement, data analytics, and program evaluation have been treated as different tasks, and those addressing them speak their own languages in their own circles. We suggest that situating performance measurement and data analytics…
Kretzschmar, A; Durand, E; Maisonnasse, A; Vallon, J; Le Conte, Y
2015-06-01
A new procedure of stratified sampling is proposed in order to establish an accurate estimation of Varroa destructor populations on sticky bottom boards of the hive. It is based on the spatial sampling theory that recommends using regular grid stratification in the case of spatially structured process. The distribution of varroa mites on sticky board being observed as spatially structured, we designed a sampling scheme based on a regular grid with circles centered on each grid element. This new procedure is then compared with a former method using partially random sampling. Relative error improvements are exposed on the basis of a large sample of simulated sticky boards (n=20,000) which provides a complete range of spatial structures, from a random structure to a highly frame driven structure. The improvement of varroa mite number estimation is then measured by the percentage of counts with an error greater than a given level. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Time-symmetric integration in astrophysics
NASA Astrophysics Data System (ADS)
Hernandez, David M.; Bertschinger, Edmund
2018-04-01
Calculating the long-term solution of ordinary differential equations, such as those of the N-body problem, is central to understanding a wide range of dynamics in astrophysics, from galaxy formation to planetary chaos. Because generally no analytic solution exists to these equations, researchers rely on numerical methods that are prone to various errors. In an effort to mitigate these errors, powerful symplectic integrators have been employed. But symplectic integrators can be severely limited because they are not compatible with adaptive stepping and thus they have difficulty in accommodating changing time and length scales. A promising alternative is time-reversible integration, which can handle adaptive time-stepping, but the errors due to time-reversible integration in astrophysics are less understood. The goal of this work is to study analytically and numerically the errors caused by time-reversible integration, with and without adaptive stepping. We derive the modified differential equations of these integrators to perform the error analysis. As an example, we consider the trapezoidal rule, a reversible non-symplectic integrator, and show that it gives secular energy error increase for a pendulum problem and for a Hénon-Heiles orbit. We conclude that using reversible integration does not guarantee good energy conservation and that, when possible, use of symplectic integrators is favoured. We also show that time-symmetry and time-reversibility are properties that are distinct for an integrator.
Exploration and extension of an improved Riemann track fitting algorithm
NASA Astrophysics Data System (ADS)
Strandlie, A.; Frühwirth, R.
2017-09-01
Recently, a new Riemann track fit which operates on translated and scaled measurements has been proposed. This study shows that the new Riemann fit is virtually as precise as popular approaches such as the Kalman filter or an iterative non-linear track fitting procedure, and significantly more precise than other, non-iterative circular track fitting approaches over a large range of measurement uncertainties. The fit is then extended in two directions: first, the measurements are allowed to lie on plane sensors of arbitrary orientation; second, the full error propagation from the measurements to the estimated circle parameters is computed. The covariance matrix of the estimated track parameters can therefore be computed without recourse to asymptotic properties, and is consequently valid for any number of observation. It does, however, assume normally distributed measurement errors. The calculations are validated on a simulated track sample and show excellent agreement with the theoretical expectations.
Asymmetric Memory Circuit Would Resist Soft Errors
NASA Technical Reports Server (NTRS)
Buehler, Martin G.; Perlman, Marvin
1990-01-01
Some nonlinear error-correcting codes more efficient in presence of asymmetry. Combination of circuit-design and coding concepts expected to make integrated-circuit random-access memories more resistant to "soft" errors (temporary bit errors, also called "single-event upsets" due to ionizing radiation). Integrated circuit of new type made deliberately more susceptible to one kind of bit error than to other, and associated error-correcting code adapted to exploit this asymmetry in error probabilities.
On-orbit assembly of a team of flexible spacecraft using potential field based method
NASA Astrophysics Data System (ADS)
Chen, Ti; Wen, Hao; Hu, Haiyan; Jin, Dongping
2017-04-01
In this paper, a novel control strategy is developed based on artificial potential field for the on-orbit autonomous assembly of four flexible spacecraft without inter-member collision. Each flexible spacecraft is simplified as a hub-beam model with truncated beam modes in the floating frame of reference and the communication graph among the four spacecraft is assumed to be a ring topology. The four spacecraft are driven to a pre-assembly configuration first and then to the assembly configuration. In order to design the artificial potential field for the first step, each spacecraft is outlined by an ellipse and a virtual leader of circle is introduced. The potential field mainly depends on the attitude error between the flexible spacecraft and its neighbor, the radial Euclidian distance between the ellipse and the circle and the classical Euclidian distance between the centers of the ellipse and the circle. It can be demonstrated that there are no local minima for the potential function and the global minimum is zero. If the function is equal to zero, the solution is not a certain state, but a set. All the states in the set are corresponding to the desired configurations. The Lyapunov analysis guarantees that the four spacecraft asymptotically converge to the target configuration. Moreover, the other potential field is also included to avoid the inter-member collision. In the control design of the second step, only small modification is made for the controller in the first step. Finally, the successful application of the proposed control law to the assembly mission is verified by two case studies.
Error baseline rates of five sample preparation methods used to characterize RNA virus populations.
Kugelman, Jeffrey R; Wiley, Michael R; Nagle, Elyse R; Reyes, Daniel; Pfeffer, Brad P; Kuhn, Jens H; Sanchez-Lockhart, Mariano; Palacios, Gustavo F
2017-01-01
Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic "no amplification" method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a "targeted" amplification method, sequence-independent single-primer amplification (SISPA) as a "random" amplification method, rolling circle reverse transcription sequencing (CirSeq) as an advanced "no amplification" method, and Illumina TruSeq RNA Access as a "targeted" enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4-5) of all compared methods.
Yu, Hao; Qian, Zheng; Liu, Huayi; Qu, Jiaqi
2018-02-14
This paper analyzes the measurement error, caused by the position of the current-carrying conductor, of a circular array of magnetic sensors for current measurement. The circular array of magnetic sensors is an effective approach for AC or DC non-contact measurement, as it is low-cost, light-weight, has a large linear range, wide bandwidth, and low noise. Especially, it has been claimed that such structure has excellent reduction ability for errors caused by the position of the current-carrying conductor, crosstalk current interference, shape of the conduction cross-section, and the Earth's magnetic field. However, the positions of the current-carrying conductor-including un-centeredness and un-perpendicularity-have not been analyzed in detail until now. In this paper, for the purpose of having minimum measurement error, a theoretical analysis has been proposed based on vector inner and exterior product. In the presented mathematical model of relative error, the un-center offset distance, the un-perpendicular angle, the radius of the circle, and the number of magnetic sensors are expressed in one equation. The comparison of the relative error caused by the position of the current-carrying conductor between four and eight sensors is conducted. Tunnel magnetoresistance (TMR) sensors are used in the experimental prototype to verify the mathematical model. The analysis results can be the reference to design the details of the circular array of magnetic sensors for current measurement in practical situations.
Error baseline rates of five sample preparation methods used to characterize RNA virus populations
Kugelman, Jeffrey R.; Wiley, Michael R.; Nagle, Elyse R.; Reyes, Daniel; Pfeffer, Brad P.; Kuhn, Jens H.; Sanchez-Lockhart, Mariano; Palacios, Gustavo F.
2017-01-01
Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic “no amplification” method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a “targeted” amplification method, sequence-independent single-primer amplification (SISPA) as a “random” amplification method, rolling circle reverse transcription sequencing (CirSeq) as an advanced “no amplification” method, and Illumina TruSeq RNA Access as a “targeted” enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4−5) of all compared methods. PMID:28182717
NASA Astrophysics Data System (ADS)
Xiong, Zhi; Zhu, J. G.; Xue, B.; Ye, Sh. H.; Xiong, Y.
2013-10-01
As a novel network coordinate measurement system based on multi-directional positioning, workspace Measurement and Positioning System (wMPS) has outstanding advantages of good parallelism, wide measurement range and high measurement accuracy, which makes it to be the research hotspots and important development direction in the field of large-scale measurement. Since station deployment has a significant impact on the measurement range and accuracy, and also restricts the use-cost, the optimization method of station deployment was researched in this paper. Firstly, positioning error model was established. Then focusing on the small network consisted of three stations, the typical deployments and error distribution characteristics were studied. Finally, through measuring the simulated fuselage using typical deployments at the industrial spot and comparing the results with Laser Tracker, some conclusions are obtained. The comparison results show that under existing prototype conditions, I_3 typical deployment of which three stations are distributed in a straight line has an average error of 0.30 mm and the maximum error is 0.50 mm in the range of 12 m. Meanwhile, C_3 typical deployment of which three stations are uniformly distributed in the half-circumference of an circle has an average error of 0.17 mm and the maximum error is 0.28 mm. Obviously, C_3 typical deployment has a higher control effect on precision than I_3 type. The research work provides effective theoretical support for global measurement network optimization in the future work.
The Effects of Discrete-Trial Training Commission Errors on Learner Outcomes: An Extension
ERIC Educational Resources Information Center
Jenkins, Sarah R.; Hirst, Jason M.; DiGennaro Reed, Florence D.
2015-01-01
We conducted a parametric analysis of treatment integrity errors during discrete-trial training and investigated the effects of three integrity conditions (0, 50, or 100 % errors of commission) on performance in the presence and absence of programmed errors. The presence of commission errors impaired acquisition for three of four participants.…
Applying integrals of motion to the numerical solution of differential equations
NASA Technical Reports Server (NTRS)
Vezewski, D. J.
1980-01-01
A method is developed for using the integrals of systems of nonlinear, ordinary, differential equations in a numerical integration process to control the local errors in these integrals and reduce the global errors of the solution. The method is general and can be applied to either scalar or vector integrals. A number of example problems, with accompanying numerical results, are used to verify the analysis and support the conjecture of global error reduction.
Applying integrals of motion to the numerical solution of differential equations
NASA Technical Reports Server (NTRS)
Jezewski, D. J.
1979-01-01
A method is developed for using the integrals of systems of nonlinear, ordinary differential equations in a numerical integration process to control the local errors in these integrals and reduce the global errors of the solution. The method is general and can be applied to either scaler or vector integrals. A number of example problems, with accompanying numerical results, are used to verify the analysis and support the conjecture of global error reduction.
ERIC Educational Resources Information Center
Chassapis, Dimitris
1999-01-01
Focuses on the process by which children develop a formal mathematical concept of the circle by using various instruments to draw circles within the context of a goal-directed drawing task. Concludes that the use of the compass in circle drawing structures the circle-drawing operation in a radically different fashion than circle tracers and…
Circling motion and screen edges as an alternative input method for on-screen target manipulation.
Ka, Hyun W; Simpson, Richard C
2017-04-01
To investigate a new alternative interaction method, called circling interface, for manipulating on-screen objects. To specify a target, the user makes a circling motion around the target. To specify a desired pointing command with the circling interface, each edge of the screen is used. The user selects a command before circling the target. To evaluate the circling interface, we conducted an experiment with 16 participants, comparing the performance on pointing tasks with different combinations of selection method (circling interface, physical mouse and dwelling interface) and input device (normal computer mouse, head pointer and joystick mouse emulator). A circling interface is compatible with many types of pointing devices, not requiring physical activation of mouse buttons, and is more efficient than dwell-clicking. Across all common pointing operations, the circling interface had a tendency to produce faster performance with a head-mounted mouse emulator than with a joystick mouse. The performance accuracy of the circling interface outperformed the dwelling interface. It was demonstrated that the circling interface has the potential as another alternative pointing method for selecting and manipulating objects in a graphical user interface. Implications for Rehabilitation A circling interface will improve clinical practice by providing an alternative pointing method that does not require physically activating mouse buttons and is more efficient than dwell-clicking. The Circling interface can also work with AAC devices.
A localization algorithm of adaptively determining the ROI of the reference circle in image
NASA Astrophysics Data System (ADS)
Xu, Zeen; Zhang, Jun; Zhang, Daimeng; Liu, Xiaomao; Tian, Jinwen
2018-03-01
Aiming at solving the problem of accurately positioning the detection probes underwater, this paper proposed a method based on computer vision which can effectively solve this problem. The theory of this method is that: First, because the shape information of the heat tube is similar to a circle in the image, we can find a circle which physical location is well known in the image, we set this circle as the reference circle. Second, we calculate the pixel offset between the reference circle and the probes in the picture, and adjust the steering gear through the offset. As a result, we can accurately measure the physical distance between the probes and the under test heat tubes, then we can know the precise location of the probes underwater. However, how to choose reference circle in image is a difficult problem. In this paper, we propose an algorithm that can adaptively confirm the area of reference circle. In this area, there will be only one circle, and the circle is the reference circle. The test results show that the accuracy of the algorithm of extracting the reference circle in the whole picture without using ROI (region of interest) of the reference circle is only 58.76% and the proposed algorithm is 95.88%. The experimental results indicate that the proposed algorithm can effectively improve the efficiency of the tubes detection.
Are Namibian “Fairy Circles” the Consequence of Self-Organizing Spatial Vegetation Patterning?
Cramer, Michael D.; Barger, Nichole N.
2013-01-01
Causes of over-dispersed barren “fairy circles” that are often surrounded by ca. 0.5 m tall peripheral grasses in a matrix of shorter (ca. 0.2 m tall) grasses in Namibian grasslands remain mysterious. It was hypothesized that the fairy circles are the consequence of self-organizing spatial vegetation patterning arising from resource competition and facilitation. We examined the edaphic properties of fairy circles and variation in fairy circle size, density and landscape occupancy (% land surface) with edaphic properties and water availability at a local scale (<50 km) and with climate and vegetation characteristics at a regional scale. Soil moisture in the barren fairy circles declines from the center towards the periphery and is inversely correlated with soil organic carbon, possibly indicating that the peripheral grass roots access soil moisture that persists into the dry season within fairy circles. Fairy circle landscape occupancy is negatively correlated with precipitation and soil [N], consistent with fairy circles being the product of resource-competition. Regional fairy circle presence/absence is highly predictable using an empirical model that includes narrow ranges of vegetation biomass, precipitation and temperature seasonality as predictor variables, indicating that fairy circles are likely a climate-dependent emergent phenomenon. This dependence of fairy circle occurrence on climate explains why fairy circles in some locations may appear and disappear over time. Fairy circles are only over-dispersed at high landscape occupancies, indicating that inter-circle competition may determine their spacing. We conclude that fairy circles are likely to be an emergent arid-grassland phenomenon that forms as a consequence of peripheral grass resource-competition and that the consequent barren circle may provide a resource-reservoir essential for the survival of the larger peripheral grasses and provides a habitat for fossicking fauna. PMID:23976962
Testing an earthquake prediction algorithm
Kossobokov, V.G.; Healy, J.H.; Dewey, J.W.
1997-01-01
A test to evaluate earthquake prediction algorithms is being applied to a Russian algorithm known as M8. The M8 algorithm makes intermediate term predictions for earthquakes to occur in a large circle, based on integral counts of transient seismicity in the circle. In a retroactive prediction for the period January 1, 1985 to July 1, 1991 the algorithm as configured for the forward test would have predicted eight of ten strong earthquakes in the test area. A null hypothesis, based on random assignment of predictions, predicts eight earthquakes in 2.87% of the trials. The forward test began July 1, 1991 and will run through December 31, 1997. As of July 1, 1995, the algorithm had forward predicted five out of nine earthquakes in the test area, which success ratio would have been achieved in 53% of random trials with the null hypothesis.
The Virtuous Circles of Clinical Information Systems: a Modern Utopia.
Degoulet, P
2016-11-10
Clinical information systems (CIS) are developed with the aim of improving both the efficiency and the quality of care. This position paper is based on the hypothesis that such vision is partly a utopian view of the emerging eSociety. Examples are drawn from 15 years of experience with the fully integrated Georges Pompidou University Hospital (HEGP) CIS and temporal data series extracted from the data warehouses of Assistance Publique - Hôpitaux de Paris (AP-HP) acute care hospitals which share the same administrative organization as HEGP. Three main virtuous circles are considered: user satisfaction vs. system use, system use vs. cost efficiency, and system use vs quality of care. In structural equation models (SEM), the positive bidirectional relationship between user satisfaction and use was only observed in the early HEGP CIS deployment phase (first four years) but disappeared in late post-adoption (≥8 years). From 2009 to 2013, financial efficiency of 20 AP-HP hospitals evaluated with stochastic frontier analysis (SFA) models diminished by 0.5% per year. The lower decrease of efficiency observed between the three hospitals equipped with a more mature CIS and the 17 other hospitals was of the same order of magnitude than the difference observed between pediatric and non-pediatric hospitals. Outcome quality benefits that would bring evidence to the system use vs. quality loop are unlikely to be obtained in a near future since they require integration with population-based outcome measures including mortality, morbidity, and quality of life that may not be easily available. Barriers to making the transformation of the utopian part of the CIS virtuous circles happen should be overcome to actually benefit the emerging eSociety.
An Evaluation of Programmed Treatment-integrity Errors during Discrete-trial Instruction
ERIC Educational Resources Information Center
Carroll, Regina A.; Kodak, Tiffany; Fisher, Wayne W.
2013-01-01
This study evaluated the effects of programmed treatment-integrity errors on skill acquisition for children with an autism spectrum disorder (ASD) during discrete-trial instruction (DTI). In Study 1, we identified common treatment-integrity errors that occur during academic instruction in schools. In Study 2, we simultaneously manipulated 3…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Itagaki, Masafumi; Miyoshi, Yoshinori; Hirose, Hideyuki
A procedure is presented for the determination of geometric buckling for regular polygons. A new computation technique, the multiple reciprocity boundary element method (MRBEM), has been applied to solve the one-group neutron diffusion equation. The main difficulty in applying the ordinary boundary element method (BEM) to neutron diffusion problems has been the need to compute a domain integral, resulting from the fission source. The MRBEM has been developed for transforming this type of domain integral into an equivalent boundary integral. The basic idea of the MRBEM is to apply repeatedly the reciprocity theorem (Green's second formula) using a sequence ofmore » higher order fundamental solutions. The MRBEM requires discretization of the boundary only rather than of the domain. This advantage is useful for extensive survey analyses of buckling for complex geometries. The results of survey analyses have indicated that the general form of geometric buckling is B[sub g][sup 2] = (a[sub n]/R[sub c])[sup 2], where R[sub c] represents the radius of the circumscribed circle of the regular polygon under consideration. The geometric constant A[sub n] depends on the type of regular polygon and takes the value of [pi] for a square and 2.405 for a circle, an extreme case that has an infinite number of sides. Values of a[sub n] for a triangle, pentagon, hexagon, and octagon have been calculated as 4.190, 2.281, 2.675, and 2.547, respectively.« less
Flat-Spectrum Radio Sources as Likely Counterparts of Unidentified INTEGRAL Sources (Research Note)
NASA Technical Reports Server (NTRS)
Molina, M.; Landi, R.; Bassani, L.; Malizia, A.; Stephen, J. B.; Bazzano, A.; Bird, A. J.; Gehrels, N.
2012-01-01
Many sources in the fourth INTEGRAL/IBIS catalogue are still unidentified since they lack an optical counterpart. An important tool that can help in identifying and classifying these sources is the cross-correlation with radio catalogues, which are very sensitive and positionally accurate. Moreover, the radio properties of a source, such as the spectrum or morphology, could provide further insight into its nature. In particular, flat-spectrum radio sources at high Galactic latitudes are likely to be AGN, possibly associated to a blazar or to the compact core of a radio galaxy. Here we present a small sample of 6 sources extracted from the fourth INTEGRAL/IBIS catalogue that are still unidentified or unclassified, but which are very likely associated with a bright, flat-spectrum radio object. To confirm the association and to study the source X-ray spectral parameters, we performed X-ray follow-up observations with Swift/XRT of all objects. We report in this note the overall results obtained from this search and discuss the nature of each individual INTEGRAL source. We find that 5 of the 6 radio associations are also detected in X-rays; furthermore, in 3 cases they are the only counterpart found. More specifically, IGR J06073-0024 is a flat-spectrum radio quasar at z = 1.08, IGR J14488-4008 is a newly discovered radio galaxy, while IGR J18129-0649 is an AGN of a still unknown type. The nature of two sources (IGR J07225-3810 and IGR J19386-4653) is less well defined, since in both cases we find another X-ray source in the INTEGRAL error circle; nevertheless, the flat-spectrum radio source, likely to be a radio loud AGN, remains a viable and, in fact, a more convincing association in both cases. Only for the last object (IGR J11544-7618) could we not find any convincing counterpart since the radio association is not an X-ray emitter, while the only X-ray source seen in the field is a G star and therefore unlikely to produce the persistent emission seen by INTEGRAL.
Qin, Feng; Zhan, Xingqun; Du, Gang
2013-01-01
Ultra-tight integration was first proposed by Abbott in 2003 with the purpose of integrating a global navigation satellite system (GNSS) and an inertial navigation system (INS). This technology can improve the tracking performances of a receiver by reconfiguring the tracking loops in GNSS-challenged environments. In this paper, the models of all error sources known to date in the phase lock loops (PLLs) of a standard receiver and an ultra-tightly integrated GNSS/INS receiver are built, respectively. Based on these models, the tracking performances of the two receivers are compared to verify the improvement due to the ultra-tight integration. Meanwhile, the PLL error distributions of the two receivers are also depicted to analyze the error changes of the tracking loops. These results show that the tracking error is significantly reduced in the ultra-tightly integrated GNSS/INS receiver since the receiver's dynamics are estimated and compensated by an INS. Moreover, the mathematical relationship between the tracking performances of the ultra-tightly integrated GNSS/INS receiver and the quality of the selected inertial measurement unit (IMU) is derived from the error models and proved by the error comparisons of four ultra-tightly integrated GNSS/INS receivers aided by different grade IMUs.
Cognitive fallacies and criminal investigations.
Ditrich, Hans
2015-03-01
The human mind is susceptible to inherent fallacies that often hamper fully rational action. Many such misconceptions have an evolutionary background and are thus difficult to avert. Deficits in the reliability of eye-witnesses are well known to legal professionals; however, less attention has been paid to such effects in crime investigators. In order to obtain an "inside view" on the role of cognitive misconceptions in criminalistic work, a list of fallacies from the literature was adapted to criminalistic settings. The statements on this list were rated by highly experienced crime scene investigators according to the assumed likelihood of these errors to appear and their severity of effect. Among others, selective perception, expectation and confirmation bias, anchoring/"pars per toto" errors and "onus probandi"--shifting the burden of proof from the investigator to the suspect--were frequently considered to negatively affect criminal investigations. As a consequence, the following measures are proposed: alerting investigating officers in their training to cognitive fallacies and promoting the exchange of experiences in peer circles of investigators on a regular basis. Furthermore, the improvement of the organizational error culture and the establishment of a failure analysis system in order to identify and alleviate error prone processes are suggested. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.
Chen, Shaoshan; He, Deyu; Wu, Yi; Chen, Huangfei; Zhang, Zaijing; Chen, Yunlei
2016-10-01
A new non-aqueous and abrasive-free magnetorheological finishing (MRF) method is adopted for processing potassium dihydrogen phosphate (KDP) crystal due to its low hardness, high brittleness, temperature sensitivity, and water solubility. This paper researches the convergence rules of the surface error of an initial single-point diamond turning (SPDT)-finished KDP crystal after MRF polishing. Currently, the SPDT process contains spiral cutting and fly cutting. The main difference of these two processes lies in the morphology of intermediate-frequency turning marks on the surface, which affects the convergence rules. The turning marks after spiral cutting are a series of concentric circles, while the turning marks after fly cutting are a series of parallel big arcs. Polishing results indicate that MRF polishing can only improve the low-frequency errors (L>10 mm) of a spiral-cutting KDP crystal. MRF polishing can improve the full-range surface errors (L>0.01 mm) of a fly-cutting KDP crystal if the polishing process is not done more than two times for single surface. We can conclude a fly-cutting KDP crystal will meet better optical performance after MRF figuring than a spiral-cutting KDP crystal with similar initial surface performance.
Where is Cultural Astronomy Going?
NASA Astrophysics Data System (ADS)
Sims, Lionel
2015-05-01
Archaeoastronomy has recently been characterised as 'going round in circles', failing to integrate a rapidly expanding body of data with the interpretive models of anthropology (Ruggles 2011). This paper locates some impediments to disciplinary growth in the legacy of our recent origins, a problematical conceptual vocabulary and a narrow and derivative theoretical base. Proposals are made for an alternative future for the discipline.
Towards a New Theory in School Management: The Theory of Positive Containment
ERIC Educational Resources Information Center
AlMusaileem, Muhammad Y.
2012-01-01
This study argues for a new theory in school management based on the notion of positive containment which benefited from the integration of the main two patterns of leadership, i.e., the democratic and the authoritarian. In this theory, the school principal has to deal with one external and five internal circles of positive containments. The…
The Impact of Cognitive Styles on Design Students' Spatial Knowledge from Virtual Environments
ERIC Educational Resources Information Center
Yildirm, Isil; Zengel, Rengin
2014-01-01
In parallel with the technological developments dominating usage of digital tools in science and education, caused the transform of knowledge in new ways. The reflection of these integration is seen in design discipline as its active role in this circle whether in practice or in the era of education, Benefit from the capabilities of new…
Assimilating Thor: How Airmen Integrate Weather Prediction
2010-06-01
atmosphere and the earth from the air and from space widened the aperture of data so as to overexpose humans to the panoply of information coming...endurance record flights circled the earth without stopping; aircraft climbed through the atmosphere into space. Weather surveillance radar...advances found congruence in the meteorological advance of ensemble weather modeling. Complex, adaptive systems like the atmosphere lend themselves to
ERIC Educational Resources Information Center
Sparapani, Ervin F.; Calahan, Patricia S.
2015-01-01
Mathematics, science, and technology are three disciplines that are highly discussed in national and international circles, especially as regards their importance to the success of young people after they leave school. With that, the purpose of the study is to examine the integration of technology into mathematics and science instruction in…
Procedure for normalization of cDNA libraries
Bonaldo, Maria DeFatima; Soares, Marcelo Bento
1997-01-01
This invention provides a method to normalize a cDNA library constructed in a vector capable of being converted to single-stranded circles and capable of producing complementary nucleic acid molecules to the single-stranded circles comprising: (a) converting the cDNA library in single-stranded circles; (b) generating complementary nucleic acid molecules to the single-stranded circles; (c) hybridizing the single-stranded circles converted in step (a) with complementary nucleic acid molecules of step (b) to produce partial duplexes to an appropriate Cot; (e) separating the unhybridized single-stranded circles from the hybridized single-stranded circles, thereby generating a normalized cDNA library.
The newest miracle drug: quality circles in hospitals.
McKinney, M M
1984-01-01
In recent years, a number of hospitals throughout the United States have been exploring the use of Japanese-style quality circles to reduce their operating expenses, improve productivity, and enhance the quality of work life for hospital employees. This article examines the organizational climate necessary for quality circles, methods used to implement quality circles, and management's role in guiding and responding to circle activities. Ideas for building and maintaining staff support are presented along with a cost/benefit analysis of quality circle programs. The author concludes that quality circles are most successful in hospitals where they are part of a larger organizational development effort. When administrators believe in their employees' ability to contribute to the institution and are willing to invest necessary time and resources in employee education and the measurement of quality circle achievements, quality circles can produce creative solutions to perplexing institutional problems.
Amplification of telomeric arrays via rolling-circle mechanism.
Nosek, Jozef; Rycovska, Adriana; Makhov, Alexander M; Griffith, Jack D; Tomaska, Lubomir
2005-03-18
Alternative (telomerase-independent) lengthening of telomeres mediated through homologous recombination is often accompanied by a generation of extrachromosomal telomeric circles (t-circles), whose role in direct promotion of recombinational telomere elongation has been recently demonstrated. Here we present evidence that t-circles in a natural telomerase-deficient system of mitochondria of the yeast Candida parapsilosis replicate independently of the linear chromosome via a rolling-circle mechanism. This is supported by an observation of (i) single-stranded DNA consisting of concatameric arrays of telomeric sequence, (ii) lasso-shaped molecules representing rolling-circle intermediates, and (iii) preferential incorporation of deoxyribonucleotides into telomeric fragments and t-circles. Analysis of naturally occurring variant t-circles revealed conserved motifs with potential function in driving the rolling-circle replication. These data indicate that extrachromosomal t-circles observed in a wide variety of organisms, including yeasts, plants, Xenopus laevis, and certain human cell lines, may represent independent replicons generating telomeric sequences and, thus, actively participating in telomere dynamics. Moreover, because of the promiscuous occurrence of t-circles across phyla, the results from yeast mitochondria have implications related to the primordial system of telomere maintenance, providing a paradigm for evolution of telomeres in nuclei of early eukaryotes.
ERIC Educational Resources Information Center
Yee, Ng Kin; Lam, Toh Tin
2008-01-01
This paper reports on students' errors in performing integration of rational functions, a topic of calculus in the pre-university mathematics classrooms. Generally the errors could be classified as those due to the students' weak algebraic concepts and their lack of understanding of the concept of integration. With the students' inability to link…
Lally, Trent; Geist, James R; Yu, Qingzhao; Himel, Van T; Sabey, Kent
2015-07-01
This study compared images displayed on 1 desktop monitor, 1 laptop monitor, and 2 tablets for the detection of contrast and working length interpretation, with a null hypothesis of no differences between the devices. Three aluminum blocks, with milled circles of varying depth, were radiographed at various exposure levels to create 45 images of varying radiographic density. Six observers viewed the images on 4 devices: Lenovo M92z desktop (Lenovo, Beijing, China), Lenovo Z580 laptop (Lenovo), iPad 3 (Apple, Cupertino, CA), and iPad mini (Apple). Observers recorded the number of circles detected for each image, and a perceptibility curve was used to compare the devices. Additionally, 42 extracted teeth were imaged with working length files affixed at various levels (short, flush, and long) relative to the anatomic apex. Observers measured the distance from file tip to tooth apex on each device. The absolute mean measurement error was calculated for each image. Analysis of variance tests compared the devices. Observers repeated their sessions 1 month later to evaluate intraobserver reliability as measured with weighted kappa tests. Interclass correlation coefficients compared interobserver reliability. There was no significant difference in perceptibility detection between the Lenovo M92z desktop, iPad 3, and iPad mini. However, on average, all 3 were significantly better than the Lenovo Z580 laptop (P values ≤.015). No significant difference in the mean absolute error was noted for working length measurements among the 4 viewing devices (P = .3509). Although all 4 viewing devices seemed comparable with regard to working length evaluation, the laptop computer screen had lower overall ability to perceive contrast differences. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
A precision analogue integrator system for heavy current measurement in MFDC resistance spot welding
NASA Astrophysics Data System (ADS)
Xia, Yu-Jun; Zhang, Zhong-Dian; Xia, Zhen-Xin; Zhu, Shi-Liang; Zhang, Rui
2016-02-01
In order to control and monitor the quality of middle frequency direct current (MFDC) resistance spot welding (RSW), precision measurement of the welding current up to 100 kA is required, for which Rogowski coils are the only viable current transducers at present. Thus, a highly accurate analogue integrator is the key to restoring the converted signals collected from the Rogowski coils. Previous studies emphasised that the integration drift is a major factor that influences the performance of analogue integrators, but capacitive leakage error also has a significant impact on the result, especially in long-time pulse integration. In this article, new methods of measuring and compensating capacitive leakage error are proposed to fabricate a precision analogue integrator system for MFDC RSW. A voltage holding test is carried out to measure the integration error caused by capacitive leakage, and an original integrator with a feedback adder is designed to compensate capacitive leakage error in real time. The experimental results and statistical analysis show that the new analogue integrator system could constrain both drift and capacitive leakage error, of which the effect is robust to different voltage levels of output signals. The total integration error is limited within ±0.09 mV s-1 0.005% s-1 or full scale at a 95% confidence level, which makes it possible to achieve the precision measurement of the welding current of MFDC RSW with Rogowski coils of 0.1% accuracy class.
A Cross-Sectional Study of the Effect of Quality Circles on Twelve Attitudinal Variables.
1985-09-01
task of rebuilding its industrial capabilities which had been largely destroyed during the war. Japanese leaders had a goal of making their country an...members, providing support when necessary, and acting as a liaison between the circles and other organizations. The circle leader or supervisor...34" " .-.-- • .- .".-",,-, . -.- -,: ".’-"’ -. -. .,-’,: Top & Middle - Management Steering Committee Supervisors . . . ....- Circle Circle Leaders Facilitator Employees Circle Members Source
Circles of support and accountability: The characteristics of core members in England and Wales.
Clarke, Martin; Warwick, Leah; Völlm, Birgit
2017-04-01
Circles of support and accountability, or Circles, use community volunteers to help reintegrate sex offenders at risk of reoffending in the community. The aims of this study are to describe the first 275 male sex offenders ('core members') in England and Wales supported by a Circle and to compare those attending the five largest Circles. As part of their monitoring activity, 10 Circles extracted data from case files, anonymised it and submitted it to Circles UK, the national oversight body. Circles have expanded rapidly with 165 (60%) of Circles commencing in the three years 2011-2013 compared with 110 in the nine years 2002-2010. Most core members were referred from the Probation Service (82%). Circles were provided to men with a range of predicted risks of reoffending - from low (26%) to very high (12%). There were some positive changes between the beginning and end of Circles, such as fewer men being unemployed and more living in their own chosen accommodation. Circles have been used to support the reintegration of a wide range of sex offenders. Given their rapid growth and flexibility, consistent recording standards are required across. These standards should be reviewed periodically to ensure all important fields of change are captured, including frequency of attendance, length per session and quality of engagement in the work. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Three Concentric Circles: Young Chinese English Learners' Perceptions of Purposeful Audiences
ERIC Educational Resources Information Center
Liu, Jack Jinghui
2015-01-01
English learners have more access to communicate with different purposeful audiences across the Three Concentric Circles of English (Kachu, 1985): the Inner Circle, the Outer Circle and the Expanding Circle. However, young language learners' purposeful audience as a focus of communication has not been emphasized as much as other linguistic…
Deep Kalman Filter: Simultaneous Multi-Sensor Integration and Modelling; A GNSS/IMU Case Study
Hosseinyalamdary, Siavash
2018-01-01
Bayes filters, such as the Kalman and particle filters, have been used in sensor fusion to integrate two sources of information and obtain the best estimate of unknowns. The efficient integration of multiple sensors requires deep knowledge of their error sources. Some sensors, such as Inertial Measurement Unit (IMU), have complicated error sources. Therefore, IMU error modelling and the efficient integration of IMU and Global Navigation Satellite System (GNSS) observations has remained a challenge. In this paper, we developed deep Kalman filter to model and remove IMU errors and, consequently, improve the accuracy of IMU positioning. To achieve this, we added a modelling step to the prediction and update steps of the Kalman filter, so that the IMU error model is learned during integration. The results showed our deep Kalman filter outperformed the conventional Kalman filter and reached a higher level of accuracy. PMID:29695119
Deep Kalman Filter: Simultaneous Multi-Sensor Integration and Modelling; A GNSS/IMU Case Study.
Hosseinyalamdary, Siavash
2018-04-24
Bayes filters, such as the Kalman and particle filters, have been used in sensor fusion to integrate two sources of information and obtain the best estimate of unknowns. The efficient integration of multiple sensors requires deep knowledge of their error sources. Some sensors, such as Inertial Measurement Unit (IMU), have complicated error sources. Therefore, IMU error modelling and the efficient integration of IMU and Global Navigation Satellite System (GNSS) observations has remained a challenge. In this paper, we developed deep Kalman filter to model and remove IMU errors and, consequently, improve the accuracy of IMU positioning. To achieve this, we added a modelling step to the prediction and update steps of the Kalman filter, so that the IMU error model is learned during integration. The results showed our deep Kalman filter outperformed the conventional Kalman filter and reached a higher level of accuracy.
Lost in Translation: the Case for Integrated Testing
NASA Technical Reports Server (NTRS)
Young, Aaron
2017-01-01
The building of a spacecraft is complex and often involves multiple suppliers and companies that have their own designs and processes. Standards have been developed across the industries to reduce the chances for critical flight errors at the system level, but the spacecraft is still vulnerable to the introduction of critical errors during integration of these systems. Critical errors can occur at any time during the process and in many cases, human reliability analysis (HRA) identifies human error as a risk driver. Most programs have a test plan in place that is intended to catch these errors, but it is not uncommon for schedule and cost stress to result in less testing than initially planned. Therefore, integrated testing, or "testing as you fly," is essential as a final check on the design and assembly to catch any errors prior to the mission. This presentation will outline the unique benefits of integrated testing by catching critical flight errors that can otherwise go undetected, discuss HRA methods that are used to identify opportunities for human error, lessons learned and challenges over ownership of testing will be discussed.
Rodgers, Joseph Lee; Beasley, William Howard; Schuelke, Matthew
2014-01-01
Many data structures, particularly time series data, are naturally seasonal, cyclical, or otherwise circular. Past graphical methods for time series have focused on linear plots. In this article, we move graphical analysis onto the circle. We focus on 2 particular methods, one old and one new. Rose diagrams are circular histograms and can be produced in several different forms using the RRose software system. In addition, we propose, develop, illustrate, and provide software support for a new circular graphical method, called Wrap-Around Time Series Plots (WATS Plots), which is a graphical method useful to support time series analyses in general but in particular in relation to interrupted time series designs. We illustrate the use of WATS Plots with an interrupted time series design evaluating the effect of the Oklahoma City bombing on birthrates in Oklahoma County during the 10 years surrounding the bombing of the Murrah Building in Oklahoma City. We compare WATS Plots with linear time series representations and overlay them with smoothing and error bands. Each method is shown to have advantages in relation to the other; in our example, the WATS Plots more clearly show the existence and effect size of the fertility differential.
Object-oriented wavefront correction in an asymmetric amplifying high-power laser system
NASA Astrophysics Data System (ADS)
Yang, Ying; Yuan, Qiang; Wang, Deen; Zhang, Xin; Dai, Wanjun; Hu, Dongxia; Xue, Qiao; Zhang, Xiaolu; Zhao, Junpu; Zeng, Fa; Wang, Shenzhen; Zhou, Wei; Zhu, Qihua; Zheng, Wanguo
2018-05-01
An object-oriented wavefront control method is proposed aiming for excellent near-field homogenization and far-field distribution in an asymmetric amplifying high-power laser system. By averaging the residual errors of the propagating beam, smaller pinholes could be employed on the spatial filters to improve the beam quality. With this wavefront correction system, the laser performance of the main amplifier system in the Shen Guang-III laser facility has been improved. The residual wavefront aberration at the position of each pinhole is below 2 µm (peak-to-valley). For each pinhole, 95% of the total laser energy is enclosed within a circle whose diameter is no more than six times the diffraction limit. At the output of the main laser system, the near-field modulation and contrast are 1.29% and 7.5%, respectively, and 95% of the 1ω (1053 nm) beam energy is contained within a 39.8 µrad circle (6.81 times the diffraction limit) under a laser fluence of 5.8 J cm-2. The measured 1ω focal spot size and near-field contrast are better than the design values of the Shen Guang-III laser facility.
Gaballa, Ahmed; Sundin, Mikael; Stikvoort, Arwen; Abumaree, Muhamed; Uzunel, Mehmet; Sairafi, Darius; Uhlin, Michael
2016-01-01
Allogeneic hematopoietic stem cell transplantation (HSCT) is a well-established treatment modality for a variety of malignant diseases as well as for inborn errors of the metabolism or immune system. Regardless of disease origin, good clinical effects are dependent on proper immune reconstitution. T cells are responsible for both the beneficial graft-versus-leukemia (GVL) effect against malignant cells and protection against infections. The immune recovery of T cells relies initially on peripheral expansion of mature cells from the graft and later on the differentiation and maturation from donor-derived hematopoietic stem cells. The formation of new T cells occurs in the thymus and as a byproduct, T cell receptor excision circles (TRECs) are released upon rearrangement of the T cell receptor. Detection of TRECs by PCR is a reliable method for estimating the amount of newly formed T cells in the circulation and, indirectly, for estimating thymic function. Here, we discuss the role of TREC analysis in the prediction of clinical outcome after allogeneic HSCT. Due to the pivotal role of T cell reconstitution we propose that TREC analysis should be included as a key indicator in the post-HSCT follow-up. PMID:27727179
Procedure for normalization of cDNA libraries
Bonaldo, M.D.; Soares, M.B.
1997-12-30
This invention provides a method to normalize a cDNA library constructed in a vector capable of being converted to single-stranded circles and capable of producing complementary nucleic acid molecules to the single-stranded circles comprising: (a) converting the cDNA library in single-stranded circles; (b) generating complementary nucleic acid molecules to the single-stranded circles; (c) hybridizing the single-stranded circles converted in step (a) with complementary nucleic acid molecules of step (b) to produce partial duplexes to an appropriate Cot; (e) separating the unhybridized single-stranded circles from the hybridized single-stranded circles, thereby generating a normalized cDNA library. 1 fig.
ERIC Educational Resources Information Center
Caglayan, Günhan
2016-01-01
A Steiner chain is defined as the sequence of n circles that are all tangent to two given non-intersecting circles. A closed chain, in particular, is one in which every circle in the sequence is tangent to the previous and next circles of the chain. In a closed Steiner chain the first and the "n"th circles of the chain are also tangent…
The Director Circle of a Central Conic Section
ERIC Educational Resources Information Center
Ayoub, Ayoub B.
2007-01-01
Each ellipse and hyperbola has a circle associated with it called the director circle. In this article, the author derives the equations of the circle for the ellipse and hyperbola through a different approach. Then the author concentrates on the director circle of the central conic given by the general quadratic equation. The content of this…
Symptoms Dark circles under eyes By Mayo Clinic Staff Dark circles under your eyes generally implies that the darkening ... eye. Fatigue is the most common cause of dark circles under your eyes. Sometimes, what appear to ...
[Sports for handicapped persons between the text and its implementation].
Negra Mahjoub, Samia; Djait, Salwa; Mahjoub, Rached; Turki, Ilhem
2003-05-01
The sports activities must occupy a paramount place in the schooling of the handicapped pupils. Indeed in addition to the development of the physical capacities, the sports activity has a positive impact on the development of the capacities of the communication and thus the integration of the pupil handicapped in his educational, family and social circle and on progress of psychomotor acquisitions. The national plan of education and the law N94-10 of August 3, 1994 relating to the sports activity in educational and university circle took part in the development and the promotion of the sports activities in the educational structures. This measurement, applied in the centers of specialized education, did not deny concerned the handicapped pupils provided education for in the colleges and normal colleges. What are the causes? Does there exist a remedy? How to introduce the sport for handicapped into the normal establishments?
High Resolution, High Precision I-Line Stepper Processing
NASA Astrophysics Data System (ADS)
Yanazawa, H.; Hasegawa, N.; Kurosaki, T.; Hashimoto, N.; Nonogaki, S.
1985-06-01
Currently, the integrated MOS dynamic RAM has as many as 256 thousand memory cells per chip based on 2 pm photolithography. Figure 1 shows the history and the prospects for progress in microfabrication technology. Feature size versus year, as reported by Bossung in 1978, is shown, as developed from independent analysis by Moore, Noyce and Gnostic concept. Circles numbered 1 and 2 show that 64K- and 256K-bit RAMs were developed in 1981 and 1984, and that their feature sizes were 3μm and 2μm, respectively. It is significant that the predictions and the real developments are so close. Furthermore, since the basic process for 3 M-bit RAMs based on 1.3μm microlithography has already been reported in conference, it is highly likely that they will become commercially available around 1987, as predicted by the circle numbered 3 based on 1.3μm microlithography.
NASA Astrophysics Data System (ADS)
Chen, H.; Chong, J.
2016-12-01
The traditional surface wave tomography is based on the ray theory, which assumes that surface wave propagates along the great-circle. The great-circle assumption is valid only when the size of the anomaly is larger than the width of the Fresnel zone and the lateral variation is relatively smooth. However, off-great-circle propagation may occur when the surface wave travels across tectonic boundaries with strong heterogeneity and sharp velocity change, e.g., continental margin, mid-ridge and sea trench, resulting in arrival angle anomaly and multi-pathing effect. The off-great-circle propagation may deviate the result of surface wave tomography based on great-circle approximation, so it is of great importance to study the off-great-circle propagation. In this study, we used the teleseismic waveforms from September 2009 to August 2011, recorded by the NECESSArray in Northeast China, to study the off-great-circle propagation of Rayleigh wave by the Beamforming method. Our results show that the off-great-circle effect increases with decreasing period. At the period of 60 s, the off-great-circle effect is relatively weak and the Rayleigh wave propagates approximately along the great-circle. While at the period of 20 s, the off-great-circle effect becomes strong, the arrival angle anomaly measured from some events can be as large as 20º, and obvious multi-pathing effect is also observed. Lateral variations of the arrival angle anomaly and phase velocity have also been found in the study region, which may be correlated with the lithosphere heterogeneity in Northeast China. Our results demonstrate the necessity to study the surface wave off-great-circle propagation. Acknowledgement: This study is financially supported by National Natural Science Foundation of China under Grant No. 41590854.
Automatic diagnosis of malaria based on complete circle-ellipse fitting search algorithm.
Sheikhhosseini, M; Rabbani, H; Zekri, M; Talebi, A
2013-12-01
Diagnosis of malaria parasitemia from blood smears is a subjective and time-consuming task for pathologists. The automatic diagnostic process will reduce the diagnostic time. Also, it can be worked as a second opinion for pathologists and may be useful in malaria screening. This study presents an automatic method for malaria diagnosis from thin blood smears. According to this fact that malaria life cycle is started by forming a ring around the parasite nucleus, the proposed approach is mainly based on curve fitting to detect parasite ring in the blood smear. The method is composed of six main phases: stain object extraction step, which extracts candidate objects that may be infected by malaria parasites. This phase includes stained pixel extraction step based on intensity and colour, and stained object segmentation by defining stained circle matching. Second step is preprocessing phase which makes use of nonlinear diffusion filtering. The process continues with detection of parasite nucleus from resulted image of previous step according to image intensity. Fourth step introduces a complete search process in which the circle search step identifies the direction and initial points for direct least-square ellipse fitting algorithm. Furthermore in the ellipse searching process, although parasite shape is completed undesired regions with high error value are removed and ellipse parameters are modified. Features are extracted from the parasite candidate region instead of whole candidate object in the fifth step. By employing this special feature extraction way, which is provided by special searching process, the necessity of employing clump splitting methods is removed. Also, defining stained circle matching process in the first step speeds up the whole procedure. Finally, a series of decision rules are applied on the extracted features to decide on the positivity or negativity of malaria parasite presence. The algorithm is applied on 26 digital images which are provided from thin blood smear films. The images are contained 1274 objects which may be infected by parasite or healthy. Applying the automatic identification of malaria on provided database showed a sensitivity of 82.28% and specificity of 98.02%. © 2013 The Authors Journal of Microscopy © 2013 Royal Microscopical Society.
ERIC Educational Resources Information Center
Cutcliffe, John
2003-01-01
Addresses historical issues in psychiatric/mental health nursing in the United Kingdom including attempts to integrate it with general nursing, the balance of theory/research and practice, and tensions over the recent shift to university-level nurse preparation. Discusses needs for the future. (Contains 42 references and commentary by Sheri…
Classification by causes of dark circles and appropriate evaluation method of dark circles.
Park, S R; Kim, H J; Park, H K; Kim, J Y; Kim, N S; Byun, K S; Moon, T K; Byun, J W; Moon, J H; Choi, G S
2016-08-01
Dark circles refer to a symptom that present darkness under the eyes. Because of improvement in the quality of life, the dark circles have been recognized as one of major cosmetic concerns. However, it is not easy to classify the dark circles because they have various causes. To select suitable instruments and detailed evaluation items, the dark circles were classified according to the causes through visual assessment, Wood's lamp test, and medical history survey for 100 subjects with dark circles. After the classification, were newly recruited for instrument conformity assessment. Through this, suitable instruments for dark circle evaluation were selected. We performed a randomized clinical trial for dark circles, a placebo-controlled double-blind study, using effective parameters of the instruments selected from the preliminary test. Dark circles of vascular type (35%) and mixed type (54%), a combination of pigmented and vascular types, were the most common. Twenty four subjects with the mixed type dark circles applied the test product (Vitamin C 3%, Vitamin A 0.1%, Vitamin E 0.5%) and placebo on randomized split-face for 8 weeks. The effective parameters (L*, a, M.I., E.I., quasi L*, quasi a* and dermal thickness) were measured during the study period. Result showed that the L* value of Chromameter(®) , Melanin index (M.I.) of Mexameter(®) and quasi L* value obtained by image analysis improved with statistical significance after applying the test product compared with the placebo product. We classified the dark circles according to the causes of the dark circles and verified the reliability of the parameter obtained by the instrument conformity assessment used in this study through the efficacy evaluation. Also based on this study, we were to suggest newly established methods which can be applied to the evaluation of efficacy of functional cosmetics for dark circles. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Conversion from Tree to Graph Representation of Requirements
NASA Technical Reports Server (NTRS)
Mayank, Vimal; Everett, David Frank; Shmunis, Natalya; Austin, Mark
2009-01-01
A procedure and software to implement the procedure have been devised to enable conversion from a tree representation to a graph representation of the requirements governing the development and design of an engineering system. The need for this procedure and software and for other requirements-management tools arises as follows: In systems-engineering circles, it is well known that requirements- management capability improves the likelihood of success in the team-based development of complex systems involving multiple technological disciplines. It is especially desirable to be able to visualize (in order to identify and manage) requirements early in the system- design process, when errors can be corrected most easily and inexpensively.
Possible Detection of Pi(exp 0)-Decay Gamma-Ray Emission from Cyg OB2 by EGRET
NASA Technical Reports Server (NTRS)
Chen, W.; White, R. L.; Bertsch, D.
1996-01-01
We report possible detection of pi (exp 0) decay radiation from Cyg OB2, a nearby (1.7 kpc) massive OB star association. The EGRET flux (greater than 100 MeV) maps clearly indicate a point source whose error circle includes both Cyg OB2 and Cyg X-3. We show that Cyg X-3 is unlikely to be the counterpart for the EGRET source, because of the marginal spatial consistency and the lack of the 4.8 hour modulation seen in other high energy emissions from Cyg X-3. If confirmed, this will be the first detection by EGRET of massive stars.
Possible detection of π^0^-decay γ-ray emission from CYG OB2 by EGRET.
NASA Astrophysics Data System (ADS)
Chen, W.; White, R. L.; Bertsch, D.
1996-12-01
We report possible detection of π^0^-decay radiation from Cyg OB2, a nearby (1.7kpc) massive OB star association. The EGRET flux (>100MeV) maps clearly indicate a point source whose error circle includes both Cyg OB2 and Cyg X-3. We show that Cyg X-3 is unlikely to be the counterpart for the EGRET source, because of the marginal spatial consistency and the lack of the 4.8-hour modulation seen in other high energy emissions from Cyg X-3. If confirmed, this will be the first detection by EGRET of massive stars.
Fluorescence errors in integrating sphere measurements of remote phosphor type LED light sources
NASA Astrophysics Data System (ADS)
Keppens, A.; Zong, Y.; Podobedov, V. B.; Nadal, M. E.; Hanselaer, P.; Ohno, Y.
2011-05-01
The relative spectral radiant flux error caused by phosphor fluorescence during integrating sphere measurements is investigated both theoretically and experimentally. Integrating sphere and goniophotometer measurements are compared and used for model validation, while a case study provides additional clarification. Criteria for reducing fluorescence errors to a degree of negligibility as well as a fluorescence error correction method based on simple matrix algebra are presented. Only remote phosphor type LED light sources are studied because of their large phosphor surfaces and high application potential in general lighting.
Ensemble-type numerical uncertainty information from single model integrations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rauser, Florian, E-mail: florian.rauser@mpimet.mpg.de; Marotzke, Jochem; Korn, Peter
2015-07-01
We suggest an algorithm that quantifies the discretization error of time-dependent physical quantities of interest (goals) for numerical models of geophysical fluid dynamics. The goal discretization error is estimated using a sum of weighted local discretization errors. The key feature of our algorithm is that these local discretization errors are interpreted as realizations of a random process. The random process is determined by the model and the flow state. From a class of local error random processes we select a suitable specific random process by integrating the model over a short time interval at different resolutions. The weights of themore » influences of the local discretization errors on the goal are modeled as goal sensitivities, which are calculated via automatic differentiation. The integration of the weighted realizations of local error random processes yields a posterior ensemble of goal approximations from a single run of the numerical model. From the posterior ensemble we derive the uncertainty information of the goal discretization error. This algorithm bypasses the requirement of detailed knowledge about the models discretization to generate numerical error estimates. The algorithm is evaluated for the spherical shallow-water equations. For two standard test cases we successfully estimate the error of regional potential energy, track its evolution, and compare it to standard ensemble techniques. The posterior ensemble shares linear-error-growth properties with ensembles of multiple model integrations when comparably perturbed. The posterior ensemble numerical error estimates are of comparable size as those of a stochastic physics ensemble.« less
NASA Astrophysics Data System (ADS)
Asgari, Jamal; Mohammadloo, Tannaz H.; Amiri-Simkooei, Ali Reza
2015-09-01
GNSS kinematic techniques are capable of providing precise coordinates in extremely short observation time-span. These methods usually determine the coordinates of an unknown station with respect to a reference one. To enhance the precision, accuracy, reliability and integrity of the estimated unknown parameters, GNSS kinematic equations are to be augmented by possible constraints. Such constraints could be derived from the geometric relation of the receiver positions in motion. This contribution presents the formulation of the constrained kinematic global navigation satellite systems positioning. Constraints effectively restrict the definition domain of the unknown parameters from the three-dimensional space to a subspace defined by the equation of motion. To test the concept of the constrained kinematic positioning method, the equation of a circle is employed as a constraint. A device capable of moving on a circle was made and the observations from 11 positions on the circle were analyzed. Relative positioning was conducted by considering the center of the circle as the reference station. The equation of the receiver's motion was rewritten in the ECEF coordinates system. A special attention is drawn onto how a constraint is applied to kinematic positioning. Implementing the constraint in the positioning process provides much more precise results compared to the unconstrained case. This has been verified based on the results obtained from the covariance matrix of the estimated parameters and the empirical results using kinematic positioning samples as well. The theoretical standard deviations of the horizontal components are reduced by a factor ranging from 1.24 to 2.64. The improvement on the empirical standard deviation of the horizontal components ranges from 1.08 to 2.2.
NASA Technical Reports Server (NTRS)
Pierson, W. J., Jr.
1984-01-01
Backscatter measurements at upwind and crosswind are simulated for five incidence angles by means of the SASS-1 model function. The effects of communication noise and attitude errors are simulated by Monte Carlo methods, and the winds are recovered by both the Sum of Square (SOS) algorithm and a Maximum Likelihood Estimater (MLE). The SOS algorithm is shown to fail for light enough winds at all incidence angles and to fail to show areas of calm because backscatter estimates that were negative or that produced incorrect values of K sub p greater than one were discarded. The MLE performs well for all input backscatter estimates and returns calm when both are negative. The use of the SOS algorithm is shown to have introduced errors in the SASS-1 model function that, in part, cancel out the errors that result from using it, but that also cause disagreement with other data sources such as the AAFE circle flight data at light winds. Implications for future scatterometer systems are given.
Quality circles: Organizational adaptations, improvements and results
NASA Technical Reports Server (NTRS)
Tortorich, R.
1985-01-01
The effective application in industry and government of quality circles work was demonstrated. The results achieved in quality and productivity improvements and cost savings are impressive. The circle process should be institutionalized within industry and government. The stages of circle program growth, innovations that help achieve circle process institutionalization, and the result achieved at Martin Marietta's Michoud Division and within the National Aeronautics and Space Administration (NASA) are addressed.
Development of a 3-D Pen Input Device
2008-09-01
of a unistroke which can be written on any surface or in the air while correcting integration errors from the...navigation frame of a unistroke, which can be written on any surface or in the air while correcting integration errors from the measurements of the IMU... be written on any surface or in the air while correcting integration errors from the measurements of the IMU (Inertial Measurement Unit) of the
Flow Mapping Based on the Motion-Integration Errors of Autonomous Underwater Vehicles
NASA Astrophysics Data System (ADS)
Chang, D.; Edwards, C. R.; Zhang, F.
2016-02-01
Knowledge of a flow field is crucial in the navigation of autonomous underwater vehicles (AUVs) since the motion of AUVs is affected by ambient flow. Due to the imperfect knowledge of the flow field, it is typical to observe a difference between the actual and predicted trajectories of an AUV, which is referred to as a motion-integration error (also known as a dead-reckoning error if an AUV navigates via dead-reckoning). The motion-integration error has been essential for an underwater glider to compute its flow estimate from the travel information of the last leg and to improve navigation performance by using the estimate for the next leg. However, the estimate by nature exhibits a phase difference compared to ambient flow experienced by gliders, prohibiting its application in a flow field with strong temporal and spatial gradients. In our study, to mitigate the phase problem, we have developed a local ocean model by combining the flow estimate based on the motion-integration error with flow predictions from a tidal ocean model. Our model has been used to create desired trajectories of gliders for guidance. Our method is validated by Long Bay experiments in 2012 and 2013 in which we deployed multiple gliders on the shelf of South Atlantic Bight and near the edge of Gulf Stream. In our recent study, the application of the motion-integration error is further extended to create a spatial flow map. Considering that the motion-integration errors of AUVs accumulate along their trajectories, the motion-integration error is formulated as a line integral of ambient flow which is then reformulated into algebraic equations. By solving an inverse problem for these algebraic equations, we obtain the knowledge of such flow in near real time, allowing more effective and precise guidance of AUVs in a dynamic environment. This method is referred to as motion tomography. We provide the results of non-parametric and parametric flow mapping from both simulated and experimental data.
Struthers, Roxanne; Hodge, Felicia Schanche; Geishirt-Cantrell, Betty; De Cora, Lorelei
2011-01-01
The Talking Circle, a culturally appropriate, 12-week educational intervention, was employed on two Northern Plains American Indian reservations to provide information on type 2 diabetes. In a phenomenological study, funded as a minority supplement to the Talking Circle intervention, the authors asked 8 American Indian participants of the Talking Circle to describe their experience of being an American Indian Talking Circle participant. Seven common themes describe the phenomenon of participating in a Talking Circle diabetic intervention. The Talking Circle technique was effective in providing information on type 2 diabetes through culturally appropriate community sharing. Type 2 diabetes is viewed by both outsiders and those involved as a chronic disease of the utmost concern in American Indian communities. PMID:14556421
Made-in-USA Quality Circles Become People-Building Tool.
ERIC Educational Resources Information Center
Cohen, Larry
1983-01-01
Discusses the use of quality circles as a human resources development tool in Middlesex Community College's Career-Oriented Peer Services tutoring center. Delineates rules for circle participants and follows the activities of two circles comprised of business-oriented and engineering-oriented students. (DMM)
Operational improvements at traffic circles : safety analysis, final report, December 2008.
DOT National Transportation Integrated Search
2008-12-01
The purpose of this study was to improve the safety and operation at three traffic circles in New : Jersey. To do this, data were collected at the traffic circles to allow researchers to model the : circles using the PARAMICS software simulation pack...
ERIC Educational Resources Information Center
Akbari, Ather H.; Aydede, Yigit
2013-01-01
For the past two decades, most immigrants who arrived in the advanced nations of the western world originated in less advanced countries of the third world. One of the main barriers to their economic integration, as viewed in the public circles of host nations, is the lack of recognition of their educational credentials based on which the…
A method for the determination of the coefficient of rolling friction using cycloidal pendulum
NASA Astrophysics Data System (ADS)
Ciornei, M. C.; Alaci, S.; Ciornei, F. C.; Romanu, I. C.
2017-08-01
The paper presents a method for experimental finding of coefficient of rolling friction appropriate for biomedical applications based on the theory of cycloidal pendulum. When a mobile circle rolls over a fixed straight line, the points from the circle describe trajectories called normal cycloids. To materialize this model, it is sufficient that a small region from boundary surfaces of a moving rigid body is spherical. Assuming pure rolling motion, the equation of motion of the cycloidal pendulum is obtained - an ordinary nonlinear differential equation. The experimental device is composed by two interconnected balls rolling over the material to be studied. The inertial characteristics of the pendulum can be adjusted via weights placed on a rod. A laser spot oscillates together to the pendulum and provides the amplitude of oscillations. After finding the experimental parameters necessary in differential equation of motion, it can be integrated using the Runge-Kutta of fourth order method. The equation was integrated for several materials and found values of rolling friction coefficients. Two main conclusions are drawn: the coefficient of rolling friction influenced significantly the amplitude of oscillation but the effect upon the period of oscillation is practically imperceptible. A methodology is proposed for finding the rolling friction coefficient and the pure rolling condition is verified.
Soil Biota and Litter Decay in High Arctic Ecosystems
NASA Astrophysics Data System (ADS)
González, G.; Rivera, F.; Makarova, O.; Gould, W. A.
2006-12-01
Frost heave action contributes to the formation of non-sorted circles in the High Arctic. Non-sorted circles tend to heave more than the surrounding tundra due to deeper thaw and the formation of ice lenses. Thus, the geomorphology, soils and vegetation on the centers of the patterned-ground feature (non-sorted circles) as compared to the surrounding soils (inter-circles) can be different. We established a decomposition experiment to look at in situ decay rates of the most dominant graminoid species on non-sorted circles and adjacent inter-circle soils along a climatic gradient in the Canadian High Arctic as a component of a larger study looking at the biocomplexity of small-featured patterned ground ecosystems. Additionally, we investigated variation in soil chemical properties and biota, including soil microarthropods and microbial composition and biomass, as they relate to climate, topographic position, and litter decay rates. Our three sites locations, from coldest to warmest, are Isachsen, Ellef Ringnes Island (ER), NU (bioclimatic subzone A); Mould Bay (MB), Prince Patrick Island, NT (bioclimatic subzone B), and Green Cabin (GC), Aulavik National Park, Thomsen River, Banks Island, NT (bioclimatic subzone C). Our sample design included the selection of 15 non-sorted circles and adjacent inter-circle areas within the zonal vegetation at each site (a total of 90 sites), and a second set of 3 non-sorted circles and adjacent inter-circle areas in dry, mesic and wet tundra at each of the sites. Soil invertebrates were sampled at each site using both pitfall traps, soil microbial biomass was determined using substrate induced respiration and bacterial populations were determined using the most probable number method. Decomposition rates were measured using litterbags and as the percent of mass remaining of Carex misandra, Luzula nivalis and Alopecuris alpinus in GC, MB and ER, respectively. Our findings indicate these graminoid species decayed significantly over time at a rate of 10-15 % mass loss / yr during the first year of decay. Decay rates are different in non-sorted circles vs. inter-circle soils along the climatic gradient. In MB, L. nivalis seems to decay faster in the inter-circle soils than in non-sorted circles (0.05
Quality/Performance Circles Three Years after Implementation.
ERIC Educational Resources Information Center
Ladwig, Dennis J.
An overview is provided of the development of quality/performance circles at Lakeshore Technical Institute (LTI), Wisconsin, and of the projects undertaken through the quality/performance circle program during its 3-year history. First, background information is provided on the use of quality circles in Japan and the United States, including…
Fostering Classroom Communities through Circling with Teacher Candidates
ERIC Educational Resources Information Center
Bouchard, Karen L.; Hollweck, Trista; Smith, J. David
2016-01-01
Classroom circles have been recognized as a valuable pedagogical approach to develop students' social-emotional learning and to establish a sense of community within a classroom. Until recently, there has been little consideration that teachers, themselves, may benefit from circling experiences. To garner a deeper understanding of circling for…
Making Morning Circle Meaningful
ERIC Educational Resources Information Center
Bruce, Susan; Fasy, Cara; Gulick, Jessica; Jones, Jill; Pike, Elizabeth
2006-01-01
Morning Circle, also known as Morning Meeting, is often a daily lesson in both general education and special education classrooms. The primary purpose of the Circle is to support each child to establish membership in the class while developing a classroom community and culture. The Responsive Classroom Approach recommends four Circle components:…
Transaction Circles with Digital Texts as a Foundation for Democratic Practices
ERIC Educational Resources Information Center
Brown, Sally
2015-01-01
Transaction circles weave together elements of guided reading and literature circles in an open conversational structure that supports students as agentive learners. Discourse within these circles utilizing digital informational texts assist in the development of democratic practices even in a time when federal mandates limit curricula and…
Perceptual Differences in Attitudes on Quality Circles.
ERIC Educational Resources Information Center
Holcomb, Lynn; Berger, Leonard
1986-01-01
A study was conducted to determine any perceptual differences toward quality circles in a chemical plant. It also tried to determine if any perceptual differences that might be found could be related to attitudes toward the circles themselves or the attitudes toward circle members. Length of service was also a factor. (CT)
Wood, Michael L; Royle, Nicola J
2017-07-12
Human herpesvirus 6A and 6B, alongside some other herpesviruses, have the striking capacity to integrate into telomeres, the terminal repeated regions of chromosomes. The chromosomally integrated forms, ciHHV-6A and ciHHV-6B, are proposed to be a state of latency and it has been shown that they can both be inherited if integration occurs in the germ line. The first step in full viral reactivation must be the release of the integrated viral genome from the telomere and here we propose various models of this release involving transcription of the viral genome, replication fork collapse, and t-circle mediated release. In this review, we also discuss the relationship between ciHHV-6 and the telomere carrying the insertion, particularly how the presence and subsequent partial or complete release of the ciHHV-6 genome may affect telomere dynamics and the risk of disease.
1981-06-01
receive for contributions to quality and productivity /4:Apdx-47. The initiative for the Quality Circle concept came from Dr Kaoru Ishikawa , a...eloquently summarized by the "Father of Quality Circles", Dr Kaoru Ishikawa . He sees that, although Japan started with the worst quality reputation among...Perceptions of Influence, Academy of Management Journal. December 1974, pp 649-bz. 49. Ishikawa , Kaoru . S.C. Circle Activities. Union of Japanese Scientists and
GENERATING FRACTAL PATTERNS BY USING p-CIRCLE INVERSION
NASA Astrophysics Data System (ADS)
Ramírez, José L.; Rubiano, Gustavo N.; Zlobec, Borut Jurčič
2015-10-01
In this paper, we introduce the p-circle inversion which generalizes the classical inversion with respect to a circle (p = 2) and the taxicab inversion (p = 1). We study some basic properties and we also show the inversive images of some basic curves. We apply this new transformation to well-known fractals such as Sierpinski triangle, Koch curve, dragon curve, Fibonacci fractal, among others. Then we obtain new fractal patterns. Moreover, we generalize the method called circle inversion fractal be means of the p-circle inversion.
Dopamine prediction error responses integrate subjective value from different reward dimensions
Lak, Armin; Stauffer, William R.; Schultz, Wolfram
2014-01-01
Prediction error signals enable us to learn through experience. These experiences include economic choices between different rewards that vary along multiple dimensions. Therefore, an ideal way to reinforce economic choice is to encode a prediction error that reflects the subjective value integrated across these reward dimensions. Previous studies demonstrated that dopamine prediction error responses reflect the value of singular reward attributes that include magnitude, probability, and delay. Obviously, preferences between rewards that vary along one dimension are completely determined by the manipulated variable. However, it is unknown whether dopamine prediction error responses reflect the subjective value integrated from different reward dimensions. Here, we measured the preferences between rewards that varied along multiple dimensions, and as such could not be ranked according to objective metrics. Monkeys chose between rewards that differed in amount, risk, and type. Because their choices were complete and transitive, the monkeys chose “as if” they integrated different rewards and attributes into a common scale of value. The prediction error responses of single dopamine neurons reflected the integrated subjective value inferred from the choices, rather than the singular reward attributes. Specifically, amount, risk, and reward type modulated dopamine responses exactly to the extent that they influenced economic choices, even when rewards were vastly different, such as liquid and food. This prediction error response could provide a direct updating signal for economic values. PMID:24453218
Native American Values and Management Education: Envisioning an Inclusive Virtuous Circle
ERIC Educational Resources Information Center
Verbos, Amy Klemm; Gladstone, Joe S.; Kennedy, Deanna M.
2011-01-01
Circles are symbols of interconnectedness. Behavioral circles can be vicious or virtuous. Many American Indians are caught in a vicious circle of exclusion from the purported benefits of Westernization, entrapment in its negative elements, and the ongoing undermining of their culture and thus their identities. Yet Native Americans, along with many…
The Value of the Math Circle for Gifted Middle School Students
ERIC Educational Resources Information Center
Burns, Barbara; Henry, Julie; McCarthy, Dianne; Tripp, Jennifer
2017-01-01
Math Circles are designed to allow students to explore mathematics using a problem-solving/inquiry approach. Many of the students attending our Math Circle are mathematically talented and curious. This study examines the perspectives of the students and their families in determining why students attend Math Circle, what they enjoy about Math…
Expanding the Reach of Extension to Underserved Audiences through Study Circles in Rural Idaho
ERIC Educational Resources Information Center
Cummins, Melissa; Petty, Barbara; Hansen, Lyle; Hoffman, Katie; Wittman, Grace
2012-01-01
Extension educators expanded the reach of their programming to underserved audiences through the implementation of Study Circles in rural Southern Idaho. Study Circles gave educators entry into communities by establishing relationships necessary for long-term change. Study Circle discussions in rural Southern Idaho led to stronger relationships…
The Acoustic Reality of the Kachruvian Circles: A Rhythmic Perspective
ERIC Educational Resources Information Center
Low, Ee Ling
2010-01-01
This paper investigates whether the rhythmic properties of varieties of English found in each of the concentric circles of Kachru's model can, in any way, be elucidated by the "Three Circles" model. A measurement and comparison of the rhythm of three varieties of English: British English (from the Inner Circle), Singapore English (from…
The Relationship of Communication to Productivity: Quality Circles as a Mediating Variable.
ERIC Educational Resources Information Center
Creagh, Sara; Smeltzer, Larry
Quality circles, small groups of employees working voluntarily toward performance improvement, have become a popular business strategy in the past decade. When effective, the quality circle may be linked directly to the increased productivity of the work group. The quality circle process may be divided into four components: identification and…
Quality Circles: Involvement, Problem-Solving, and Recognition.
ERIC Educational Resources Information Center
Moretz, H. Lynn
1983-01-01
The media production department of Central Piedmont Community College (CPCC) began quality circle meetings in January 1981 after studying the process of quality circles and obtaining the understanding and support of the college administration. A quality circle is a small group of people doing similar work who voluntarily meet on a regular basis to…
The "Us" in Discuss: Grouping in Literature Circles
ERIC Educational Resources Information Center
Batchelor, Katherine
2012-01-01
This article describes one middle school teacher's use of literature circles using heterogeneous grouping. It begins with a brief rationale for using literature circles in the language arts classroom. Next, it describes techniques to form literature circles. Then, it shares how to build and establish a supportive environment within each group. It…
ERIC Educational Resources Information Center
Boyarsky, Terry L.
2006-01-01
Circles are everywhere and endlessly intriguing. We know, sense, and feel them in time, space, sound, and the cycles of nature. A person's life contains spirals, repetitions, going out and coming back. Poets write of circles; composers write song cycles. Circles are at the root of the curriculum, concepts deep yet accessible, infinite in their…
Accuracy of tree diameter estimation from terrestrial laser scanning by circle-fitting methods
NASA Astrophysics Data System (ADS)
Koreň, Milan; Mokroš, Martin; Bucha, Tomáš
2017-12-01
This study compares the accuracies of diameter at breast height (DBH) estimations by three initial (minimum bounding box, centroid, and maximum distance) and two refining (Monte Carlo and optimal circle) circle-fitting methods The circle-fitting algorithms were evaluated in multi-scan mode and a simulated single-scan mode on 157 European beech trees (Fagus sylvatica L.). DBH measured by a calliper was used as reference data. Most of the studied circle-fitting algorithms significantly underestimated the mean DBH in both scanning modes. Only the Monte Carlo method in the single-scan mode significantly overestimated the mean DBH. The centroid method proved to be the least suitable and showed significantly different results from the other circle-fitting methods in both scanning modes. In multi-scan mode, the accuracy of the minimum bounding box method was not significantly different from the accuracies of the refining methods The accuracy of the maximum distance method was significantly different from the accuracies of the refining methods in both scanning modes. The accuracy of the Monte Carlo method was significantly different from the accuracy of the optimal circle method in only single-scan mode. The optimal circle method proved to be the most accurate circle-fitting method for DBH estimation from point clouds in both scanning modes.
Conditions for the optical wireless links bit error ratio determination
NASA Astrophysics Data System (ADS)
Kvíčala, Radek
2017-11-01
To determine the quality of the Optical Wireless Links (OWL), there is necessary to establish the availability and the probability of interruption. This quality can be defined by the optical beam bit error rate (BER). Bit error rate BER presents the percentage of successfully transmitted bits. In practice, BER runs into the problem with the integration time (measuring time) determination. For measuring and recording of BER at OWL the bit error ratio tester (BERT) has been developed. The 1 second integration time for the 64 kbps radio links is mentioned in the accessible literature. However, it is impossible to use this integration time for singularity of coherent beam propagation.
The Astrometric Recognition of the Solar Clementine Gnomon (1702)
NASA Astrophysics Data System (ADS)
Sigismondi, Costantino
The Clementine gnomon has been built in 1702 to measure the Earth's obliquity variation. For this reason the pinhole was located in the walls of Diocletian's times (305 a. D.) in order to remain stable along the centuries, but its original form and position have been modified. We used an astrometric method to recover the original position of the pinhole: reshaping the pinhole to a circle of 1.5 cm of diameter, the positions of the Northern and Southern limbs have been compared with the ephemerides. A sistematic shift of 4.5 mm Southward of the whole solar image shows that the original pinhole was 4.5 mm North of the actual position, as the images in the Bianchini's book (1703) suggest. The oval shape of the actual pinhole is also wrong. Using a circle the larger solar spots are clearly visible. Some reference stars of the catalogue of Philippe de la Hire (1702), used originally for measuring the ecliptic latitude of the Sun, are written next to the meridian line, but after the last restauration (2000), four of them are wrongly located. Finally the deviation from the true North, of the meridian line's azimuth confirms the value recovered in 1750. This, with the local deviations of a true line, will remain as systematic error, like for all these historical instruments.
COMPLETENESS OF CIRCLE OF WILLIS IN ASYMPTOMATIC AND SYMPTOMATIC EXTRACRANIAL CAROTID DISEASE.
Manojlovic, Vladimir; Popovic, Vlandan; Nikoloc, Dragan; Milosevic, Dorde; Pasternak, Janko; Budakov, Nebojsa
2016-11-01
This research has been aimed at determining whether incomplete Circle of Willis in patients with significant extracranial carotid stenosis is associated with a higher incidence of neurological symptomatology and/or ischemnic cerebral lesions. The research was conducted as a prospective study which comprised 211 patients who underwent surgical treatment of extracranial carotid disease at the Department of Vascular Surgery in Novi Sad and 102 patients in the control group. Each patient underwent preoperative magnetic resonance imaging and magnetic resonance angiography with visualization of cerebral parenchyma. extracranial and intracranial cerebral circulation. Assessment of Circle of Willis morphology was performed by 3D time-of-fight magnetic resonance angiogram sequence analysis. The patients were divided into two groups: group I - the patients with'complete Circle of Willis and group II - the patients with incomplete Circle of Willis i.e. with the disruption of anterior and/ or ipsilateral posterior circulation - regarding the side of signif icant carotid stenosis. Out of 211 patients who -were operated during a two-year period, 133 had the complete Circle of Willis. while 78 patients had the incomplete Circle of Willis. Out of 111 patients with symptomatic carotid disease or silent cerebral infarction, 52.5% (58) had the complete Circle of' Willis and 47.5% (53) had the incomplete Circle of Willis. It was shown to be statistically different (P = 0.0146) in relation with the asymptomatic group of patients (100), where the frequency of the complete Circle of Willis was 75% (75) while the insufficiency of anterior or ipsilateral posterior collateral ization was found in 25% (25). In the control group there were significantly fewer cases of developed collateral flow and the complete Circle of Willis (41%) compared to the operated patients with extracranial carotid stenosis (63%) (P= 0.0003). Incompleteness of Circle of Willis is associated with more frequent occurrence of neurological symptomatology or ischemic lesions of brain parenchyma in operated patients with significant extracranial carotid stenosis. The control group without extracranial carotid stenosis had less developed collaterals of Circle of Willis compared to extracranial carotid patients.
Study on Network Error Analysis and Locating based on Integrated Information Decision System
NASA Astrophysics Data System (ADS)
Yang, F.; Dong, Z. H.
2017-10-01
Integrated information decision system (IIDS) integrates multiple sub-system developed by many facilities, including almost hundred kinds of software, which provides with various services, such as email, short messages, drawing and sharing. Because the under-layer protocols are different, user standards are not unified, many errors are occurred during the stages of setup, configuration, and operation, which seriously affect the usage. Because the errors are various, which may be happened in different operation phases, stages, TCP/IP communication protocol layers, sub-system software, it is necessary to design a network error analysis and locating tool for IIDS to solve the above problems. This paper studies on network error analysis and locating based on IIDS, which provides strong theory and technology supports for the running and communicating of IIDS.
Automatic image acquisition processor and method
Stone, William J.
1986-01-01
A computerized method and point location system apparatus is disclosed for ascertaining the center of a primitive or fundamental object whose shape and approximate location are known. The technique involves obtaining an image of the object, selecting a trial center, and generating a locus of points having a predetermined relationship with the center. Such a locus of points could include a circle. The number of points overlying the object in each quadrant is obtained and the counts of these points per quadrant are compared. From this comparison, error signals are provided to adjust the relative location of the trial center. This is repeated until the trial center overlies the geometric center within the predefined accuracy limits.
Automatic image acquisition processor and method
Stone, W.J.
1984-01-16
A computerized method and point location system apparatus is disclosed for ascertaining the center of a primitive or fundamental object whose shape and approximate location are known. The technique involves obtaining an image of the object, selecting a trial center, and generating a locus of points having a predetermined relationship with the center. Such a locus of points could include a circle. The number of points overlying the object in each quadrant is obtained and the counts of these points per quadrant are compared. From this comparison, error signals are provided to adjust the relative location of the trial center. This is repeated until the trial center overlies the geometric center within the predefined accuracy limits.
ERIC Educational Resources Information Center
Mengual, Gloria
This document, which is based on information gathered during a 1998 study of how study circle programs contribute to community problem solving, presents best practices for producing community-wide study circles. The best practices are illustrated through stories that are grouped into five sections on the following themes: (1) creating a…
ERIC Educational Resources Information Center
Field, M. J.; Harrison, A. B.
Quality circles attempt to satisfy both task and personal needs through staff involvement in solving work-related problems. This paper summarizes quality circle theory, applies it to school settings, and suggests a framework for introducing the process to educational institutions. After briefly defining quality circles, the article presents two…
Mismanagement and Quality Circles: How Middle Managers Influence Direct Participation.
ERIC Educational Resources Information Center
Brennan, Maire
1991-01-01
Case studies of five Scottish companies found that four of their quality circles programs had ceased. Essential to the success of quality circles were changes in the systems of reward, communication, and decision making and the cooperation and support of middle managers, who may see quality circles as a threat and who control the resources they…
Expanding-Circle Students Learning "Standard English" in the Outer-Circle Asia
ERIC Educational Resources Information Center
Kobayashi, Yoko
2011-01-01
Drawing upon Kachru's concentric circles of English, the present study explores whether middle-class Japanese students who chose to study English solo at private language schools in Singapore diverge from many others who (wish to) study inner-circle English. The study is stimulated by the repeated interdisciplinary findings that, in spite of the…
Circles of Support and Personalization: Exploring the Economic Case
ERIC Educational Resources Information Center
Wistow, Gerald; Perkins, Margaret; Knapp, Martin; Bauer, Annette; Bonin, Eva-Maria
2016-01-01
Circles of Support aim to enable people with learning disabilities (and others) to live full lives as part of their communities. As part of a wider study of the economic case for community capacity building conducted from 2012 to 2014, we conducted a mixed methods study of five Circles in North West England. Members of these Circles were…
Children with Autism and Peer Group Support: "Using Circles of Friends".
ERIC Educational Resources Information Center
Whitaker, Philip; Barratt, Penny; Joy, Helen; Potter, Mo; Thomas, George
1998-01-01
Explains the "circle of friends approach" as one strategy aimed at using peer group support to promote the inclusion of children with autism into mainstream schools. It describes use of the approach with six autistic children in years 3 to 10 of British mainstream schools. Evaluation comments by the circle leaders, circle members, and…
The Chicken and the Egg: Inviting Response and Talk through Socratic Circles
ERIC Educational Resources Information Center
Styslinger, Mary E.; Pollock, Timothy
2010-01-01
This collaborative inquiry answers the following questions: 1) What is the nature of talk during Socratic Circles? 2) What is student response to talk? 3) How might knowing more about student response to talk and the nature of talk improve teaching during Socratic Circles? The article first describes the process of implementing Socratic Circles,…
Getting Started with Literature Circles. The Bill Harp Professional Teachers Library Series.
ERIC Educational Resources Information Center
Noe, Katherine L. Schlick; Johnson, Nancy J.
Designed to help teachers get started using literature circles in their classrooms, this book gives teachers a boost to begin, offers some insights from other teachers, and helps teachers clarify where to go next. It notes that literature circles (or literature study groups, book clubs, or discussion circles) take many forms and engage students in…
Guided Discovery of the Nine-Point Circle Theorem and Its Proof
ERIC Educational Resources Information Center
Buchbinder, Orly
2018-01-01
The nine-point circle theorem is one of the most beautiful and surprising theorems in Euclidean geometry. It establishes an existence of a circle passing through nine points, all of which are related to a single triangle. This paper describes a set of instructional activities that can help students discover the nine-point circle theorem through…
An unidentified TeV source in the vicinity of Cygnus OB2
NASA Astrophysics Data System (ADS)
Aharonian, F.; Akhperjanian, A.; Beilicke, M.; Bernlöhr, K.; Börst, H.; Bojahr, H.; Bolz, O.; Coarasa, T.; Contreras, J.; Cortina, J.; Denninghoff, S.; Fonseca, V.; Girma, M.; Götting, N.; Heinzelmann, G.; Hermann, G.; Heusler, A.; Hofmann, W.; Horns, D.; Jung, I.; Kankanyan, R.; Kestel, M.; Kettler, J.; Kohnle, A.; Konopelko, A.; Kornmeyer, H.; Kranich, D.; Krawczynski, H.; Lampeitl, H.; Lopez, M.; Lorenz, E.; Lucarelli, F.; Magnussen, N.; Mang, O.; Meyer, H.; Milite, M.; Mirzoyan, R.; Moralejo, A.; Ona, E.; Panter, M.; Plyasheshnikov, A.; Prahl, J.; Pühlhofer, G.; Rauterberg, G.; Reyes, R.; Rhode, W.; Ripken, J.; Röhring, A.; Rowell, G. P.; Sahakian, V.; Samorski, M.; Schilling, M.; Schröder, F.; Siems, M.; Sobzynska, D.; Stamm, W.; Tluczykont, M.; Völk, H. J.; Wiedner, C. A.; Wittek, W.; Uchiyama, Y.; Takahashi, T.; HEGRA Collaboration
2002-10-01
Deep observation ( ~ 113 hrs) of the Cygnus region at TeV energies using the HEGRA stereoscopic system of air Čerenkov telescopes has serendipitously revealed a signal positionally inside the core of the OB association Cygnus OB2, at the edge of the 95% error circle of the EGRET source 3EG J2033+4118, and ~ 0.5o north of Cyg X-3. The source centre of gravity is RA alphaJ2000: 20h 32m 07s+/- 9.2sstat +/-2.2ssys, Dec deltaJ2000: +41o 30' 30''+/- 2.0'stat +/- 0.4'sys. The source is steady, has a post-trial significance of +4.6sigma , indication for extension with radius 5.6' at the ~ 3sigma level, and has a differential power-law flux with hard photon index of -1.9 +/-0.3stat +/-0.3sys. The integral flux above 1 TeV amounts ~ 3% that of the Crab. No counterpart for the TeV source at other wavelengths is presently identified, and its extension would disfavour an exclusive pulsar or AGN origin. If associated with Cygnus OB2, this dense concentration of young, massive stars provides an environment conducive to multi-TeV particle acceleration and likely subsequent interaction with a nearby gas cloud. Alternatively, one could envisage gamma -ray production via a jet-driven termination shock.
Synergism of the method of characteristics and CAD technology for neutron transport calculation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Z.; Wang, D.; He, T.
2013-07-01
The method of characteristics (MOC) is a very popular methodology in neutron transport calculation and numerical simulation in recent decades for its unique advantages. One of the key problems determining whether the MOC can be applied in complicated and highly heterogeneous geometry is how to combine an effective geometry processing method with MOC. Most of the existing MOC codes describe the geometry by lines and arcs with extensive input data, such as circles, ellipses, regular polygons and combination of them. Thus they have difficulty in geometry modeling, background meshing and ray tracing for complicated geometry domains. In this study, amore » new idea making use of a CAD solid modeler MCAM which is a CAD/Image-based Automatic Modeling Program for Neutronics and Radiation Transport developed by FDS Team in China was introduced for geometry modeling and ray tracing of particle transport to remove these geometrical limitations mentioned above. The diamond-difference scheme was applied to MOC to reduce the spatial discretization error of the flat flux approximation in theory. Based on MCAM and MOC, a new MOC code was developed and integrated into SuperMC system, which is a Super Multi-function Computational system for neutronics and radiation simulation. The numerical testing results demonstrated the feasibility and effectiveness of the new idea for geometry treatment in SuperMC. (authors)« less
ERIC Educational Resources Information Center
National Indian Council on Aging, Albuquerque, NM.
Focusing on six major topics to be addressed at the 1981 White House Conference (economic security, physical and mental health, social well being, older Americans as a national resource, creating an age-integrated society, and research), the National Indian Conference attracted 1,165 persons from more than 140 tribes (592 being Indian elders over…
Optimization of processing parameters of UAV integral structural components based on yield response
NASA Astrophysics Data System (ADS)
Chen, Yunsheng
2018-05-01
In order to improve the overall strength of unmanned aerial vehicle (UAV), it is necessary to optimize the processing parameters of UAV structural components, which is affected by initial residual stress in the process of UAV structural components processing. Because machining errors are easy to occur, an optimization model for machining parameters of UAV integral structural components based on yield response is proposed. The finite element method is used to simulate the machining parameters of UAV integral structural components. The prediction model of workpiece surface machining error is established, and the influence of the path of walking knife on residual stress of UAV integral structure is studied, according to the stress of UAV integral component. The yield response of the time-varying stiffness is analyzed, and the yield response and the stress evolution mechanism of the UAV integral structure are analyzed. The simulation results show that this method is used to optimize the machining parameters of UAV integral structural components and improve the precision of UAV milling processing. The machining error is reduced, and the deformation prediction and error compensation of UAV integral structural parts are realized, thus improving the quality of machining.
Learning mechanisms to limit medication administration errors.
Drach-Zahavy, Anat; Pud, Dorit
2010-04-01
This paper is a report of a study conducted to identify and test the effectiveness of learning mechanisms applied by the nursing staff of hospital wards as a means of limiting medication administration errors. Since the influential report ;To Err Is Human', research has emphasized the role of team learning in reducing medication administration errors. Nevertheless, little is known about the mechanisms underlying team learning. Thirty-two hospital wards were randomly recruited. Data were collected during 2006 in Israel by a multi-method (observations, interviews and administrative data), multi-source (head nurses, bedside nurses) approach. Medication administration error was defined as any deviation from procedures, policies and/or best practices for medication administration, and was identified using semi-structured observations of nurses administering medication. Organizational learning was measured using semi-structured interviews with head nurses, and the previous year's reported medication administration errors were assessed using administrative data. The interview data revealed four learning mechanism patterns employed in an attempt to learn from medication administration errors: integrated, non-integrated, supervisory and patchy learning. Regression analysis results demonstrated that whereas the integrated pattern of learning mechanisms was associated with decreased errors, the non-integrated pattern was associated with increased errors. Supervisory and patchy learning mechanisms were not associated with errors. Superior learning mechanisms are those that represent the whole cycle of team learning, are enacted by nurses who administer medications to patients, and emphasize a system approach to data analysis instead of analysis of individual cases.
Calvo, Roque; D’Amato, Roberto; Gómez, Emilio; Domingo, Rosario
2016-01-01
The development of an error compensation model for coordinate measuring machines (CMMs) and its integration into feature measurement is presented. CMMs are widespread and dependable instruments in industry and laboratories for dimensional measurement. From the tip probe sensor to the machine display, there is a complex transformation of probed point coordinates through the geometrical feature model that makes the assessment of accuracy and uncertainty measurement results difficult. Therefore, error compensation is not standardized, conversely to other simpler instruments. Detailed coordinate error compensation models are generally based on CMM as a rigid-body and it requires a detailed mapping of the CMM’s behavior. In this paper a new model type of error compensation is proposed. It evaluates the error from the vectorial composition of length error by axis and its integration into the geometrical measurement model. The non-explained variability by the model is incorporated into the uncertainty budget. Model parameters are analyzed and linked to the geometrical errors and uncertainty of CMM response. Next, the outstanding measurement models of flatness, angle, and roundness are developed. The proposed models are useful for measurement improvement with easy integration into CMM signal processing, in particular in industrial environments where built-in solutions are sought. A battery of implementation tests are presented in Part II, where the experimental endorsement of the model is included. PMID:27690052
Topping, David J.; Rubin, David M.; Wright, Scott A.; Melis, Theodore S.
2011-01-01
Several common methods for measuring suspended-sediment concentration in rivers in the United States use depth-integrating samplers to collect a velocity-weighted suspended-sediment sample in a subsample of a river cross section. Because depth-integrating samplers are always moving through the water column as they collect a sample, and can collect only a limited volume of water and suspended sediment, they collect only minimally time-averaged data. Four sources of error exist in the field use of these samplers: (1) bed contamination, (2) pressure-driven inrush, (3) inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration, and (4) inadequate time averaging. The first two of these errors arise from misuse of suspended-sediment samplers, and the third has been the subject of previous study using data collected in the sand-bedded Middle Loup River in Nebraska. Of these four sources of error, the least understood source of error arises from the fact that depth-integrating samplers collect only minimally time-averaged data. To evaluate this fourth source of error, we collected suspended-sediment data between 1995 and 2007 at four sites on the Colorado River in Utah and Arizona, using a P-61 suspended-sediment sampler deployed in both point- and one-way depth-integrating modes, and D-96-A1 and D-77 bag-type depth-integrating suspended-sediment samplers. These data indicate that the minimal duration of time averaging during standard field operation of depth-integrating samplers leads to an error that is comparable in magnitude to that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. This random error arising from inadequate time averaging is positively correlated with grain size and does not largely depend on flow conditions or, for a given size class of suspended sediment, on elevation above the bed. Averaging over time scales >1 minute is the likely minimum duration required to result in substantial decreases in this error. During standard two-way depth integration, a depth-integrating suspended-sediment sampler collects a sample of the water-sediment mixture during two transits at each vertical in a cross section: one transit while moving from the water surface to the bed, and another transit while moving from the bed to the water surface. As the number of transits is doubled at an individual vertical, this error is reduced by ~30 percent in each size class of suspended sediment. For a given size class of suspended sediment, the error arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration depends only on the number of verticals collected, whereas the error arising from inadequate time averaging depends on both the number of verticals collected and the number of transits collected at each vertical. Summing these two errors in quadrature yields a total uncertainty in an equal-discharge-increment (EDI) or equal-width-increment (EWI) measurement of the time-averaged velocity-weighted suspended-sediment concentration in a river cross section (exclusive of any laboratory-processing errors). By virtue of how the number of verticals and transits influences the two individual errors within this total uncertainty, the error arising from inadequate time averaging slightly dominates that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. Adding verticals to an EDI or EWI measurement is slightly more effective in reducing the total uncertainty than adding transits only at each vertical, because a new vertical contributes both temporal and spatial information. However, because collection of depth-integrated samples at more transits at each vertical is generally easier and faster than at more verticals, addition of a combination of verticals and transits is likely a more practical approach to reducing the total uncertainty in most field situatio
NASA Astrophysics Data System (ADS)
Ravi, Sujith; Wang, Lixin; Kaseke, Kudzai Farai; Buynevich, Ilya V.; Marais, Eugene
2017-02-01
Vegetation patterns such as rings, bands, and spots are recurrent characteristics of resource-limited arid and semiarid ecosystems. One of the most recognizable vegetation patterns is the millions of circular patches, often referred to as "fairy circles," within the arid grassland matrix extending over hundreds of kilometers in the Namib Desert. Several modeling studies have highlighted the role of plant-soil interactions in the formation of these fairy circles. However, little is known about the spatial and temporal variabilities of hydrological processes inside a fairy circle. In particular, a detailed field assessment of hydrological and soil properties inside and outside the fairy circles is limited. We conducted extensive measurements of infiltration rate, soil moisture, grass biometric, and sediment grain-size distribution from multiple circles and interspaces in the Namib Desert. Our results indicate that considerable heterogeneity in hydrological processes exists within the fairy circles, resulting from the presence of coarser particles in the inner bare soil areas, whereas concentration of fine soil occurs on the vegetated edges. The trapping of aeolian and water-borne sediments by plants may result in the observed soil textural changes beneath the vegetation, which in turn, explains the heterogeneity in hydrological processes such as infiltration and runoff. Our investigation provides new insights and experimental data on the ecohydrological processes associated with fairy circles, from a less studied location devoid of sand termite activity within the circles. The results seem to provide support to the "self-organization hypothesis" of fairy circle formation attributed to the antiphase spatial biomass-water distributions.
NASA Astrophysics Data System (ADS)
Klieger, Aviva; Ben-Hur, Yehuda; Bar-Yossef, Nurit
2010-04-01
The study examines the professional development of junior-high-school teachers participating in the Israeli "Katom" (Computer for Every Class, Student and Teacher) Program, begun in 2004. A three-circle support and training model was developed for teachers' professional development. The first circle applies to all teachers in the program; the second, to all teachers at individual schools; the third to teachers of specific disciplines. The study reveals and describes the attitudes of science teachers to the integration of laptop computers and to the accompanying professional development model. Semi-structured interviews were conducted with eight science teachers from the four schools participating in the program. The interviews were analyzed according to the internal relational framework taken from the information that arose from the interviews. Two factors influenced science teachers' professional development: (1) Introduction of laptops to the teachers and students. (2) The support and training system. Interview analysis shows that the disciplinary training is most relevant to teachers and they are very interested in belonging to the professional science teachers' community. They also prefer face-to-face meetings in their school. Among the difficulties they noted were the new learning environment, including control of student computers, computer integration in laboratory work and technical problems. Laptop computers contributed significantly to teachers' professional and personal development and to a shift from teacher-centered to student-centered teaching. One-to-One laptops also changed the schools' digital culture. The findings are important for designing concepts and models for professional development when introducing technological innovation into the educational system.
A Spring Playscape Project: Building a Tree Circle
ERIC Educational Resources Information Center
Keeler, Rusty
2009-01-01
The Tree Circle is a green gathering area for children made by planting trees in a circle. For children, the Tree Circle becomes a magical place for dramatic play, quiet retreat, or lively nature exploration. For teachers and parents it becomes a shady grove for snacks and stories. The trees create a sweet spot that changes during the seasons and…
National Forest System working circles: a question of size and ownership composition
Robert J. Hrubes
1976-01-01
Allowable-cut (potential yield) levels on National Forest land are determined for planning units called working circles. The size of working circles has been increased over the past 30 years to the present scale which is often coincident with National Forest boundaries. Larger working circles have recently been considered because of the anticipated impacts on timber...
van den Heuvel, Charles; Weingart, Scott B; Spelt, Nils; Nellen, Henk
2016-01-01
Science in the early modern world depended on openness in scholarly communication. On the other hand, a web of commercial, political, and religious conflicts required broad measures of secrecy and confidentiality; similar measures were integral to scholarly rivalries and plagiarism. This paper analyzes confidentiality and secrecy in intellectual and technological knowledge exchange via letters and drawings. We argue that existing approaches to understanding knowledge exchange in early modern Europe--which focus on the Republic of Letters as a unified entity of corresponding scholars--can be improved upon by analyzing multilayered networks of communication. We describe a data model to analyze circles of confidence and cultures of secrecy in intellectual and technological knowledge exchanges. Finally, we discuss the outcomes of a first experiment focusing on the question of how personal and professional/official relationships interact with confidentiality and secrecy, based on a case study of the correspondence of Hugo Grotius.
Quantum communications system with integrated photonic devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nordholt, Jane E.; Peterson, Charles Glen; Newell, Raymond Thorson
Security is increased in quantum communication (QC) systems lacking a true single-photon laser source by encoding a transmitted optical signal with two or more decoy-states. A variable attenuator or amplitude modulator randomly imposes average photon values onto the optical signal based on data input and the predetermined decoy-states. By measuring and comparing photon distributions for a received QC signal, a single-photon transmittance is estimated. Fiber birefringence is compensated by applying polarization modulation. A transmitter can be configured to transmit in conjugate polarization bases whose states of polarization (SOPs) can be represented as equidistant points on a great circle on themore » Poincare sphere so that the received SOPs are mapped to equidistant points on a great circle and routed to corresponding detectors. Transmitters are implemented in quantum communication cards and can be assembled from micro-optical components, or transmitter components can be fabricated as part of a monolithic or hybrid chip-scale circuit.« less
Chang, Kuo-Tsai; Lee, Chun-Wei
2008-04-01
This paper investigates design, fabrication and test of thin disc piezoelectric transformers (PTs) based on piezoelectric buzzers with gap circles at different diameters of the gap circles. The performance test is focused on characteristics of voltage gains, including maximum voltage gains and maximum-gain frequencies, for each piezoelectric transformer under different load conditions. Both a piezoelectric buzzer and a gap circle on a silver electrode of the buzzer are needed to build any type of the PTs. Here, the gap circle is used to form a ring-shaped input electrode and a circle-shaped output electrode for each piezoelectric transformer. To do so, both structure and connection of a PT are first expressed. Then, operating principle of a PT and its related vibration mode observed by a carbon-power imaging technique are described. Moreover, an experimental setup for characterizing each piezoelectric transformer is constructed. Finally, effects of diameters of the gap circles on characteristics of voltage gains at different load resistances are discussed.
NASA Astrophysics Data System (ADS)
Männer, R.
1989-12-01
This paper describes a systolic array processor for a ring image Cherenkov counter which is capable of identifying pairs of electron circles with a known radius and a certain minimum distance within 15 μs. The processor is a very flexible and fast device. It consists of 128 x 128 processing elements (PEs), where one PE is assigned to each pixel of the image. All PEs run synchronously at 40 MHz. The identification of electron circles is done by correlating the detector image with the proper circle circumference. Circle centers are found by peak detection in the correlation result. A second correlation with a circle disc allows circles of closed electron pairs to be rejected. The trigger decision is generated if a pseudo adder detects at least two remaining circles. The device is controlled by a freely programmable sequencer. A VLSI chip containing 8 x 8 PEs is being developed using a VENUS design system and will be produced in 2μ CMOS technology.
Circles South East: the first 10 years 2002-2012.
Bates, Andrew; Williams, Dominic; Wilson, Chris; Wilson, Robin J
2014-07-01
This article describes the first 10 years of the implementation of Circles of Support and Accountability (Circles) in the management of sexual offenders in South-East England by Circles South East (CSE). The Circles of 71 core members are reviewed in detail, with reference to demographic data, offense and sentencing histories, risk assessment data, and considerations regarding Multi-Agency Public Protection Arrangements. A group of 71 comparison subjects who were referred to CSE and deemed suitable for but did not receive the service was identified. Follow-up behaviors of both groups are examined (including all forms of reconviction, breach of orders, and prison recall). Over a comparable follow-up period of 55 months, the incidence of violent and contact sexual reconviction in the comparison group was significantly higher than for the Circles cohort. Comparisons are made between expected and actual levels of sexual reconviction, with the Circles cohort showing lower than expected rate of sexual reconviction but not to a statistically significant degree. © The Author(s) 2013.
Wear simulation of apex seal in rotary engine under mixed lubrication
NASA Astrophysics Data System (ADS)
Jiang, Hanying; Zuo, Zhengxing; Liu, Jinxiang
2018-05-01
In this work, the wear of apex seal's running face under mixed lubrication is studied. Numerical simulation is carried out by employing the couple model of Reynolds equation, Greenwood and Tripp model and Archard's wear law. The simulation is performed both for one circle and multi circle. In the multi circle simulation, the change of contact position due to wear is considered. A method that is able to find the new contact position based on the updated apex seal's contour profile is proposed, validated and used. The result of multi circle simulation indicates that contact position changes obviously around the maximum swing angles both on leading and trailing sides with the increase number of circles. The wear depth distribution becomes more uniform with the increase of operation circle number.
Algebraic criteria for positive realness relative to the unit circle.
NASA Technical Reports Server (NTRS)
Siljak, D. D.
1973-01-01
A definition is presented of the circle positive realness of real rational functions relative to the unit circle in the complex variable plane. The problem of testing this kind of positive reality is reduced to the algebraic problem of determining the distribution of zeros of a real polynomial with respect to and on the unit circle. Such reformulation of the problem avoids the search for explicit information about imaginary poles of rational functions. The stated algebraic problem is solved by applying the polynomial criteria of Marden (1966) and Jury (1964), and a completely recursive algorithm for circle positive realness is obtained.
Numerically Integrated Orbits of the Major Saturnian Satellites fit to Earthbased Observations
NASA Technical Reports Server (NTRS)
Jacobson, R. A.; Vaughan, R. M.
1993-01-01
We have fit numerically integrated orbits of the eight major satellites of Saturn to all available astrometric and meridian circle observations for the period of 1971 to 1992. The integration was carried out in cartesian coordinates in the J2000 system. The force model included the gravitational effects of the oblate primary, the mutual perturbations of the satellites, and perturbations due to Jupiter and the Sun. Values of the gravitational parameters of the Saturnian system, e.g. planet and satellite masses, were taken from Campbell, et. al., 1989, only the epoch state vectors of the satellites were adjusted to obtain orbits which fit the observations. All astrometric data was processed in the form of satellite relative positions which were weighted according to observer and opposition to reflect the varying data quality...
Drach-Zahavy, A; Somech, A; Admi, H; Peterfreund, I; Peker, H; Priente, O
2014-03-01
Attention in the ward should shift from preventing medication administration errors to managing them. Nevertheless, little is known in regard with the practices nursing wards apply to learn from medication administration errors as a means of limiting them. To test the effectiveness of four types of learning practices, namely, non-integrated, integrated, supervisory and patchy learning practices in limiting medication administration errors. Data were collected from a convenient sample of 4 hospitals in Israel by multiple methods (observations and self-report questionnaires) at two time points. The sample included 76 wards (360 nurses). Medication administration error was defined as any deviation from prescribed medication processes and measured by a validated structured observation sheet. Wards' use of medication administration technologies, location of the medication station, and workload were observed; learning practices and demographics were measured by validated questionnaires. Results of the mixed linear model analysis indicated that the use of technology and quiet location of the medication cabinet were significantly associated with reduced medication administration errors (estimate=.03, p<.05 and estimate=-.17, p<.01 correspondingly), while workload was significantly linked to inflated medication administration errors (estimate=.04, p<.05). Of the learning practices, supervisory learning was the only practice significantly linked to reduced medication administration errors (estimate=-.04, p<.05). Integrated and patchy learning were significantly linked to higher levels of medication administration errors (estimate=-.03, p<.05 and estimate=-.04, p<.01 correspondingly). Non-integrated learning was not associated with it (p>.05). How wards manage errors might have implications for medication administration errors beyond the effects of typical individual, organizational and technology risk factors. Head nurse can facilitate learning from errors by "management by walking around" and monitoring nurses' medication administration behaviors. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Farah, Jeffrey J.
1992-01-01
Developing a robust, task level, error recovery and on-line planning architecture is an open research area. There is previously published work on both error recovery and on-line planning; however, none incorporates error recovery and on-line planning into one integrated platform. The integration of these two functionalities requires an architecture that possesses the following characteristics. The architecture must provide for the inclusion of new information without the destruction of existing information. The architecture must provide for the relating of pieces of information, old and new, to one another in a non-trivial rather than trivial manner (e.g., object one is related to object two under the following constraints, versus, yes, they are related; no, they are not related). Finally, the architecture must be not only a stand alone architecture, but also one that can be easily integrated as a supplement to some existing architecture. This thesis proposal addresses architectural development. Its intent is to integrate error recovery and on-line planning onto a single, integrated, multi-processor platform. This intelligent x-autonomous platform, called the Planning Coordinator, will be used initially to supplement existing x-autonomous systems and eventually replace them.
ERIC Educational Resources Information Center
Leon, Yanerys; Wilder, David A.; Majdalany, Lina; Myers, Kristin; Saini, Valdeep
2014-01-01
We conducted two experiments to evaluate the effects of errors of omission and commission during alternative reinforcement of compliance in young children. In Experiment 1, we evaluated errors of omission by examining two levels of integrity during alternative reinforcement (20 and 60%) for child compliance following no treatment (baseline) versus…
NASA Astrophysics Data System (ADS)
Chen, Haopeng; Ni, Sidao; Chu, Risheng; Chong, Jiajun; Liu, Zhikun; Zhu, Liangbao
2018-05-01
Surface waves are generally assumed to propagate along great-circle paths in most surface-wave tomography. However, when lateral heterogeneity is strong, off-great-circle propagation may occur and deteriorate surface wave tomography results based on the great-circle assumption. In this study, we used teleseismic waveforms recorded by the NECESSArray in Northeast China to study off-great-circle propagation of Rayleigh waves using the beamforming method and evaluated the influence of off-great-circle propagation on event-based surface wave tomography. The results show that arrival angle anomalies generally increase with decreasing period. The arrival angle anomalies at 60 and 50 s periods are smaller than that at 40 and 30 s periods, which indicates that the off-great-circle propagation is relatively weak for longer periods. At 30 s period, the arrival angle anomalies are relatively larger and some of the measurements can exceed 20°, which represents a strong off-great-circle propagation effect. In some areas, the arrival angle anomalies of adjacent events differ significantly, which may be attributed to multipathing propagation of surface waves. To evaluate the influence of off-great-circle propagation on event-based surface wave tomography, we used measured arrival angle anomalies to correct two-station phase velocity measurements, and performed azimuthal anisotropy tomography using dispersion datasets with and without the arrival angle correction. At longer periods, such as 60 s, the influence of off-great-circle propagation on surface wave tomography is weak even though the corrected model has better data fit than the uncorrected model. However, the influence of off-great-circle propagation is non-negligible at short periods. The tomography results at 30 s period show that the differences in phase velocity, the strength of anisotropy and the fast direction can be as large as 1.5 per cent, 1.0 per cent and 30°, respectively. Furthermore, the corrected phase velocity is systematically lower than that without correction. This study illustrates the necessity of studying the off-great-circle propagation of surface waves to improve the accuracy of event-based surface wave tomography, especially for shorter periods.
Error Estimates for Numerical Integration Rules
ERIC Educational Resources Information Center
Mercer, Peter R.
2005-01-01
The starting point for this discussion of error estimates is the fact that integrals that arise in Fourier series have properties that can be used to get improved bounds. This idea is extended to more general situations.
2011-01-01
Background Orthopaedic research projects focusing on small displacements in a small measurement volume require a radiation free, three dimensional motion analysis system. A stereophotogrammetrical motion analysis system can track wireless, small, light-weight markers attached to the objects. Thereby the disturbance of the measured objects through the marker tracking can be kept at minimum. The purpose of this study was to develop and evaluate a non-position fixed compact motion analysis system configured for a small measurement volume and able to zoom while tracking small round flat markers in respect to a fiducial marker which was used for the camera pose estimation. Methods The system consisted of two web cameras and the fiducial marker placed in front of them. The markers to track were black circles on a white background. The algorithm to detect a centre of the projected circle on the image plane was described and applied. In order to evaluate the accuracy (mean measurement error) and precision (standard deviation of the measurement error) of the optical measurement system, two experiments were performed: 1) inter-marker distance measurement and 2) marker displacement measurement. Results The first experiment of the 10 mm distances measurement showed a total accuracy of 0.0086 mm and precision of ± 0.1002 mm. In the second experiment, translations from 0.5 mm to 5 mm were measured with total accuracy of 0.0038 mm and precision of ± 0.0461 mm. The rotations of 2.25° amount were measured with the entire accuracy of 0.058° and the precision was of ± 0.172°. Conclusions The description of the non-proprietary measurement device with very good levels of accuracy and precision may provide opportunities for new, cost effective applications of stereophotogrammetrical analysis in musculoskeletal research projects, focusing on kinematics of small displacements in a small measurement volume. PMID:21284867
Rolling-circle amplification under topological constraints
Kuhn, Heiko; Demidov, Vadim V.; Frank-Kamenetskii, Maxim D.
2002-01-01
We have performed rolling-circle amplification (RCA) reactions on three DNA templates that differ distinctly in their topology: an unlinked DNA circle, a linked DNA circle within a pseudorotaxane-type structure and a linked DNA circle within a catenane. In the linked templates, the single-stranded circle (dubbed earring probe) is threaded, with the aid of two peptide nucleic acid openers, between the two strands of double-stranded DNA (dsDNA). We have found that the RCA efficiency of amplification was essentially unaffected when the linked templates were employed. By showing that the DNA catenane remains intact after RCA reactions, we prove that certain DNA polymerases can carry out the replicative synthesis under topological constraints allowing detection of several hundred copies of a dsDNA marker without DNA denaturation. Our finding may have practical implications in the area of DNA diagnostics. PMID:11788721
Research on the error model of airborne celestial/inertial integrated navigation system
NASA Astrophysics Data System (ADS)
Zheng, Xiaoqiang; Deng, Xiaoguo; Yang, Xiaoxu; Dong, Qiang
2015-02-01
Celestial navigation subsystem of airborne celestial/inertial integrated navigation system periodically correct the positioning error and heading drift of the inertial navigation system, by which the inertial navigation system can greatly improve the accuracy of long-endurance navigation. Thus the navigation accuracy of airborne celestial navigation subsystem directly decides the accuracy of the integrated navigation system if it works for long time. By building the mathematical model of the airborne celestial navigation system based on the inertial navigation system, using the method of linear coordinate transformation, we establish the error transfer equation for the positioning algorithm of airborne celestial system. Based on these we built the positioning error model of the celestial navigation. And then, based on the positioning error model we analyze and simulate the positioning error which are caused by the error of the star tracking platform with the MATLAB software. Finally, the positioning error model is verified by the information of the star obtained from the optical measurement device in range and the device whose location are known. The analysis and simulation results show that the level accuracy and north accuracy of tracking platform are important factors that limit airborne celestial navigation systems to improve the positioning accuracy, and the positioning error have an approximate linear relationship with the level error and north error of tracking platform. The error of the verification results are in 1000m, which shows that the model is correct.
Making Residents Part of the Safety Culture: Improving Error Reporting and Reducing Harms.
Fox, Michael D; Bump, Gregory M; Butler, Gabriella A; Chen, Ling-Wan; Buchert, Andrew R
2017-01-30
Reporting medical errors is a focus of the patient safety movement. As frontline physicians, residents are optimally positioned to recognize errors and flaws in systems of care. Previous work highlights the difficulty of engaging residents in identification and/or reduction of medical errors and in integrating these trainees into their institutions' cultures of safety. The authors describe the implementation of a longitudinal, discipline-based, multifaceted curriculum to enhance the reporting of errors by pediatric residents at Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center. The key elements of this curriculum included providing the necessary education to identify medical errors with an emphasis on systems-based causes, modeling of error reporting by faculty, and integrating error reporting and discussion into the residents' daily activities. The authors tracked monthly error reporting rates by residents and other health care professionals, in addition to serious harm event rates at the institution. The interventions resulted in significant increases in error reports filed by residents, from 3.6 to 37.8 per month over 4 years (P < 0.0001). This increase in resident error reporting correlated with a decline in serious harm events, from 15.0 to 8.1 per month over 4 years (P = 0.01). Integrating patient safety into the everyday resident responsibilities encourages frequent reporting and discussion of medical errors and leads to improvements in patient care. Multiple simultaneous interventions are essential to making residents part of the safety culture of their training hospitals.
Quality Control in construction.
1984-01-01
behavioral scientists. In 1962, Dr. Kaoru Ishikawa gave shape to the form of training which featured intradepartmental groups of ten or so workers seated...and Japanese circles bears closer scrutiny. 4.3.1 Japanese Ingredients of Quality The founder of quality circles, Dr. Kaoru Ishikawa , gives six...around 51 a table; hence the name Quality Control Circle. 4 Dr. 0 Ishikawa was an engineering professor at Tokyo University, and the circles were
NASA Astrophysics Data System (ADS)
Robinson, Andrew
2018-04-01
The founder of the Vienna Circle – a polymathic and influential group of intellectuals dedicated to the philosophy of science from the late 1920s until the Nazi takeover of Austria in 1938 – was German philosopher and physicist Moritz Schlick. Karl Sigmund's latest book – Exact Thinking in Demented Times: the Vienna Circle and the Epic Quest for the Foundations of Science – tells the story of the Vienna Circle's ideas and personalities.
Calculation of Latitude and Longitude for Points on Perimeter of a Circle on a Sphere
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morris, Heidi E.
2015-08-14
This document describes the calculation of the Earth-Centered Earth Fixed (ECEF) coordinates for points lying on the perimeter of a circle. Here, the perimeter of the circle lies on the surface of the sphere and the center of the planar circle is below the surface. These coordinates are converted to latitude and longitude for mapping fields on the surface of the earth.
Empirical Evaluation of Different Feature Representations for Social Circles Detection
2015-06-16
study and compare the performance on the available labelled Facebook data from the Kaggle competition on learning social circles in networks . We...Kaggle competition on learning social circles in networks [5]. The data consist of hand- labelled friendship egonets from Facebook and a set of 57...16. SECURITY CLASSIFICATION OF: Social circles detection is a special case of community detection in social network that is currently attracting a
Therapeutic self-disclosure in integrative psychotherapy: When is this a clinical error?
Ziv-Beiman, Sharon; Shahar, Golan
2016-09-01
Ascending to prominence in virtually all forms of psychotherapy, therapist self-disclosure (TSD) has recently been identified as a primarily integrative intervention (Ziv-Beiman, 2013). In the present article, we discuss various instances in which using TSD in integrative psychotherapy might constitute a clinical error. First, we briefly review extant theory and empirical research on TSD, followed by our preferred version of integrative psychotherapy (i.e., a version of Wachtel's Cyclical Psychodynamics [Wachtel, 1977, 1997, 2014]), which we title cognitive existential psychodynamics. Next, we provide and discuss three examples in which implementing TSD constitutes a clinical error. In essence, we submit that using TSD constitutes an error when patients, constrained by their representational structures (object relations), experience the subjectivity of the other as impinging, and thus propels them to "react" instead of "emerge." (PsycINFO Database Record (c) 2016 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Tsai, Chien-Chung; Huang, Yi-Chao; Yang, Tsa-Hsien; Chen, Jen-Chieh
2006-01-01
The concentric circles type and saw-tooth type of micro grating device based upon the diffraction theory are proposed in this study. The geometry dimension of micro optical device is 200 × 200 μm2, the interval of grating is 4 μm, and the depth is 0.75 μm. The Micro Array Thermal Actuator, MATA, is applied to drive the micro grating device, and the pre-elevating structure is designed to lift the micro grating device by the residual stress of polysilicon combined with metal. The micro grating device is fabricated by Surface Micromachining for applications and research technology platform, SMart, common process. The incident ray of He-Ne laser focused by a lens which focal length is 250 mm is applied to be the light source for the experiment, and then analyzes the optical information of the outgoing ray. From the experimental results, the basic optical features are examined based upon the concentric circles type and saw-tooth type of micro grating device, respectively. The outgoing ray angle of central spot is 60° in theory. The measurements are 59.475° for the concentric circles type and 59.88° for the saw-tooth type. The outgoing ray angle of the first stripe is 46.9° in theory, and 46.81° for the concentric circles type and 46.67° for the saw-tooth type are measured from the experiment. The variation of outgoing ray angle is smaller than 1% compared the measurement results with theory of diffraction on the central spot and first stripe characteristics. The work successfully demonstrates the micro grating device with highly accurate performance by the verification of optical information. All of the efforts will be contributed to Controlled Blazed Diffraction micro grating device, CBDMG, and that will be the main device of Integrate Opto-Electronics applied on display to develop in the future.
Crustal Strike-Slip Faulting along Small Circle Paths in the Northwestern United States
NASA Astrophysics Data System (ADS)
Brocher, T. M.; Wells, R. E.; Lamb, A. P.; Weaver, C. S.
2015-12-01
Late Cenozoic and Quaternary faults, seismicity lineaments, and focal mechanisms provide evidence that clockwise rotation of Washington and Oregon is accommodated by north-directed thrusting and strike-slip deformation in the Washington segment of the Cascadia forearc. Curvilinear NW- to NNW-trending high-angle strike-slip faults and seismicity lineaments define small circles around an Euler pole (117.7°W, 47.9°N) of rotation relative to North America that approximates GPS-derived poles for the rotation of eastern Washington and the Snake River Plain. Although the lengths of strike-slip faults that follow small circle paths suggest maximum earthquake magnitudes of M6.6 to M7.2, their slip rates calculated from the Euler pole are low (0.3 to 0.5 mm/yr). Many normal faults in the Lewis and Clark Zone in Montana, the Centennial fault system north of the Snake River Plain, west of the Wasatch Front, in the northern Basin and Range, and locally east of the Oregon Cascade arc are radial to this pole of rotation, suggesting that these normal faults help accommodate this crustal rotation. Regions undergoing contraction in western Washington and northwestern Oregon are separated from those to the east undergoing extension by lines radial to the Euler pole. In our regional kinematic model, dextral faults along small circles connect SW-directed crustal extension in the Intermountain Seismic Belt and E-directed extension in the Cascade arc south of Mount Hood to N-directed contraction in the Olympic Peninsula, Puget Lowland, and the Yakima Fold and Thrust Belt. The lack of Quaternary faulting and seismicity in the Oregon segment of the forearc is consistent with its clockwise rotation as a rigid block. Potential drivers of the crustal rotation include westward slab rollback and the Yellowstone geoid high, and the overall velocity field may integrate the response of rotating blocks and distributed deformation between them.
NASA Astrophysics Data System (ADS)
Taniai, Tetsuyuki; Ito, Ken-Ichi; Sakamaki, Hiroshi
In this paper, we presented a method and knowledge about a practical and project management education and local contribution obtained through the student activities of “Environmental science laboratory circle in the College of Science and technology in Nihon University” from 1991 to 2001. In this circle, four major projects were acted such as research, protection, clean up and enlightenment projects. Due to some problems from inside or outside of this circle, this circle projects have been stopped. The diffusion and popularization of the internet technology will help to resolve some of these problems.
1982-04-01
the transformation 2 1 V I " |€ , (22) 121 I which transforms a unit circle in the Z plane to a unit upper half ...circle (and to the real axis from -1. to 1.) in the 4 plane as illustrated in Fig. 6. I Zpbns rpIUII A A , FIGURE 6. , CIRCLE TO HALF CIRCLE MAPPING The ...an airfoil, or inlet, etc. ... ) to a rectangle (or equivalently to a circle or half plane ). The cumputing time required for this step is
Component analysis and synthesis of dark circles under the eyes using a spectral image
NASA Astrophysics Data System (ADS)
Akaho, Rina; Hirose, Misa; Ojima, Nobutoshi; Igarashi, Takanori; Tsumura, Norimichi
2017-02-01
This paper proposes to apply nonlinear estimation of chromophore concentrations: melanin, oxy-hemoglobin, deoxyhemoglobin and shading to the real hyperspectral image of skin. Skin reflectance is captured in the wavelengths between 400nm and 700nm by hyperspectral scanner. Five-band wavelengths data are selected from skin reflectance. By using the cubic function which obtained by Monte Carlo simulation of light transport in multi-layered tissue, chromophore concentrations and shading are determined by minimize residual sum of squares of reflectance. When dark circles are appeared under the eyes, the subject looks tired and older. Therefore, woman apply cosmetic cares to remove dark circles. It is not clear about the relationship between color and chromophores distribution in the dark circles. Here, we applied the separation method of the skin four components to hyperspectral image of dark circle, and the separated components are modulated and synthesized. The synthesized images are evaluated to know which components are contributed into the appearance of dark circles. Result of the evaluation shows that the cause of dark circles for the one subject was mainly melanin pigmentation.
Izenberg, Jacob M; Fullilove, Mindy Thompson
2016-04-01
The aim of this study was to investigate the contribution of main streets to community social cohesion, a factor important to health. Prior work suggests that casual contact in public space, which we call "sociability," facilitates more sustained social bonds in the community. We appropriate the term "hospitality" to describe a main street's propensity to support a density of such social interactions. Hospitality is a result of the integrity and complex contents of the main street and surrounding area. We examine this using a typology we term "box-circle-line" to represent the streetscape (the box), the local neighborhood (the circle), and the relationship to the regional network of streets (the line). Through field visits to 50 main streets in New Jersey and elsewhere, and a systematic qualitative investigation of main streets in a densely interconnected urban region (Essex County, New Jersey), we observed significant variation in main street hospitality, which generally correlated closely with sociability. Physical elements such as street wall, neighborhood elements such as connectivity, inter-community elements such as access and perceived welcome, and socio-political elements such as investment and racial discrimination were identified as relevant to main street hospitality. We describe the box-circle-line as a theoretical model for main street hospitality that links these various factors and provides a viable framework for further research into main street hospitality, particularly with regard to geographic health disparities.
Kletting, P; Schimmel, S; Kestler, H A; Hänscheid, H; Luster, M; Fernández, M; Bröer, J H; Nosske, D; Lassmann, M; Glatting, G
2013-10-01
Calculation of the time-integrated activity coefficient (residence time) is a crucial step in dosimetry for molecular radiotherapy. However, available software is deficient in that it is either not tailored for the use in molecular radiotherapy and/or does not include all required estimation methods. The aim of this work was therefore the development and programming of an algorithm which allows for an objective and reproducible determination of the time-integrated activity coefficient and its standard error. The algorithm includes the selection of a set of fitting functions from predefined sums of exponentials and the choice of an error model for the used data. To estimate the values of the adjustable parameters an objective function, depending on the data, the parameters of the error model, the fitting function and (if required and available) Bayesian information, is minimized. To increase reproducibility and user-friendliness the starting values are automatically determined using a combination of curve stripping and random search. Visual inspection, the coefficient of determination, the standard error of the fitted parameters, and the correlation matrix are provided to evaluate the quality of the fit. The functions which are most supported by the data are determined using the corrected Akaike information criterion. The time-integrated activity coefficient is estimated by analytically integrating the fitted functions. Its standard error is determined assuming Gaussian error propagation. The software was implemented using MATLAB. To validate the proper implementation of the objective function and the fit functions, the results of NUKFIT and SAAM numerical, a commercially available software tool, were compared. The automatic search for starting values was successfully tested for reproducibility. The quality criteria applied in conjunction with the Akaike information criterion allowed the selection of suitable functions. Function fit parameters and their standard error estimated by using SAAM numerical and NUKFIT showed differences of <1%. The differences for the time-integrated activity coefficients were also <1% (standard error between 0.4% and 3%). In general, the application of the software is user-friendly and the results are mathematically correct and reproducible. An application of NUKFIT is presented for three different clinical examples. The software tool with its underlying methodology can be employed to objectively and reproducibly estimate the time integrated activity coefficient and its standard error for most time activity data in molecular radiotherapy.
NASA Technical Reports Server (NTRS)
Belcastro, Celeste M.; Fischl, Robert; Kam, Moshe
1992-01-01
This paper presents a strategy for dynamically monitoring digital controllers in the laboratory for susceptibility to electromagnetic disturbances that compromise control integrity. The integrity of digital control systems operating in harsh electromagnetic environments can be compromised by upsets caused by induced transient electrical signals. Digital system upset is a functional error mode that involves no component damage, can occur simultaneously in all channels of a redundant control computer, and is software dependent. The motivation for this work is the need to develop tools and techniques that can be used in the laboratory to validate and/or certify critical aircraft controllers operating in electromagnetically adverse environments that result from lightning, high-intensity radiated fields (HIRF), and nuclear electromagnetic pulses (NEMP). The detection strategy presented in this paper provides dynamic monitoring of a given control computer for degraded functional integrity resulting from redundancy management errors, control calculation errors, and control correctness/effectiveness errors. In particular, this paper discusses the use of Kalman filtering, data fusion, and statistical decision theory in monitoring a given digital controller for control calculation errors.
DOT National Transportation Integrated Search
1971-05-01
The report describes a dynamic model of a traffic circle which has been implemented on a CRT display terminal. The model includes sufficient parameters to allow changes in the structure of the traffic circle, the frequency of traffic introduced to th...
ERIC Educational Resources Information Center
Ren, Wei
2014-01-01
Yoo's (2014) article raises a number of questions concerning local teachers' status and the ownership of English in the Expanding Circle. In this article, I address five issues that I see as most important relating to the ownership of English and empowering local teachers in the Expanding Circle. I provide up-to-date evidence of World…
Circles of Support and Accountability for Sex Offenders: A Systematic Review of Outcomes.
Clarke, Martin; Brown, Susan; Völlm, Birgit
2017-08-01
We conducted a systematic review of studies reporting on the effectiveness of Circles of Support and Accountability (Circles). Circles use volunteers to provide support for sex offenders living in the community. We searched 10 databases up to the end of 2013 and identified 3 relevant outcome studies. An additional 12 papers or reports were identified by searching reference lists, Google, and contacting key authors and Circles providers to obtain unpublished data. These 15 studies comprised one randomized controlled trial, three retrospective cohorts with matched controls, and 11 case series. The majority reported measures of recidivism, particularly reconviction. The 4 studies with controls generally reported that participation in Circles was associated with lower recidivism although there were few statistically significant differences. Few studies examined changes in risk or psychosocial outcomes. A number of methodological issues are discussed. Longer term, prospective follow-up studies with control groups are required to address these issues.
Hromadka, T.V.; Guymon, G.L.
1985-01-01
An algorithm is presented for the numerical solution of the Laplace equation boundary-value problem, which is assumed to apply to soil freezing or thawing. The Laplace equation is numerically approximated by the complex-variable boundary-element method. The algorithm aids in reducing integrated relative error by providing a true measure of modeling error along the solution domain boundary. This measure of error can be used to select locations for adding, removing, or relocating nodal points on the boundary or to provide bounds for the integrated relative error of unknown nodal variable values along the boundary.
An adaptive staircase procedure for the E-Prime programming environment.
Hairston, W David; Maldjian, Joseph A
2009-01-01
Many studies need to determine a subject's threshold for a given task. This can be achieved efficiently using an adaptive staircase procedure. While the logic and algorithms for staircases have been well established, the few pre-programmed routines currently available to researchers require at least moderate programming experience to integrate into new paradigms and experimental settings. Here, we describe a freely distributed routine developed for the E-Prime programming environment that can be easily integrated into any experimental protocol with only a basic understanding of E-Prime. An example experiment (visual temporal-order-judgment task) where subjects report the order of occurrence of two circles illustrates the behavior and consistency of the routine.
NASA Technical Reports Server (NTRS)
Weaver, W. L.; Green, R. N.
1980-01-01
Geometric shape factors were computed and applied to satellite simulated irradiance measurements to estimate Earth emitted flux densities for global and zonal scales and for areas smaller than the detector field of view (FOV). Wide field of view flat plate detectors were emphasized, but spherical detectors were also studied. The radiation field was modeled after data from the Nimbus 2 and 3 satellites. At a satellite altitude of 600 km, zonal estimates were in error 1.0 to 1.2 percent and global estimates were in error less than 0.2 percent. Estimates with unrestricted field of view (UFOV) detectors were about the same for Lambertian and limb darkening radiation models. The opposite was found for restricted field of view detectors. The UFOV detectors are found to be poor estimators of flux density from the total FOV and are shown to be much better as estimators of flux density from a circle centered at the FOV with an area significantly smaller than that for the total FOV.
Characterising a holographic modal phase mask for the detection of ocular aberrations
NASA Astrophysics Data System (ADS)
Corbett, A. D.; Leyva, D. Gil; Diaz-Santana, L.; Wilkinson, T. D.; Zhong, J. J.
2005-12-01
The accurate measurement of the double-pass ocular wave front has been shown to have a broad range of applications from LASIK surgery to adaptively corrected retinal imaging. The ocular wave front can be accurately described by a small number of Zernike circle polynomials. The modal wave front sensor was first proposed by Neil et al. and allows the coefficients of the individual Zernike modes to be measured directly. Typically the aberrations measured with the modal sensor are smaller than those seen in the ocular wave front. In this work, we investigated a technique for adapting a modal phase mask for the sensing of the ocular wave front. This involved extending the dynamic range of the sensor by increasing the pinhole size to 2.4mm and optimising the mask bias to 0.75λ. This was found to decrease the RMS error by up to a factor of three for eye-like aberrations with amplitudes up to 0.2μm. For aberrations taken from a sample of real-eye measurements a 20% decrease in the RMS error was observed.
NASA Astrophysics Data System (ADS)
Okie, J.; Gould, W. A.; González, G.
2006-12-01
Patterned ground is a ubiquitous feature in the Arctic and the related variation in microtopographic relief strongly affects biotic and abiotic patterns and processes. Patterned ground features are polygenic in origin and are often found superimposed in a complex pattern of multiple features. We investigated the relationship between thaw depth, micro-relief, the cover of vascular, bryophyte, cryptogamic crust and bare ground along transects traversing non-sorted circles and small non-sorted polygons at 8 research sites along a climatic gradient in bioclimatic subzones A-E in the North American Arctic. Non-sorted circles are the result of differential frost heave with circle centers typically showing greater heave during freezing than inter circle areas. Differential heave is a function of climate, soil texture, soil moisture, and vegetation cover. Differential heave and subsidence creates fine-scale gradients in microtopography that affect soil moisture, exposure to winds, and development of vegetation and soils. Non-sorted circles typically range from 20 to 200 cm in diameter and are most common in subzones C-E. Often superimposed on these features are the development of small non-sorted polygons 10-30 cm in diameter, and fine-scale desiccation cracking at a scale of less than 10 cm. These are most common in subzones A-C. We established three 20 m transects in zonal vegetation at each site. Thaw depth, micro-relief, and ground cover were measured at 10 cm intervals along each transect. Additionally, we measured vascular plant beta diversity in a set of 25 x 25 cm quadrates on 15 circles and 15 inter circles at each site. The resulting pattern of thaw depth and micro-relief is correlated with both summer temperatures and vegetation cover. The variability and degree of micro-relief decrease from the Low to the High Arctic. Non-sorted circle centers had deeper active layer than inter circle areas along the gradient. Thaw depths increase linearly with the degree of bare ground and nonlinearly with summer warmth. This unimodal pattern of shallower active layer at the warmest and coldest sites is due to the interaction of climate and the insulating vegetation layer. Greatest thaw depths are found on bare non-sorted circles in subzone C. Beta diversity is greatest in subzone D, where vegetated inter circle areas differ markedly from more barren non- sorted circles.
[Continuum based fast Fourier transform processing of infrared spectrum].
Liu, Qing-Jie; Lin, Qi-Zhong; Wang, Qin-Jun; Li, Hui; Li, Shuai
2009-12-01
To recognize ground objects with infrared spectrum, high frequency noise removing is one of the most important phases in spectrum feature analysis and extraction. A new method for infrared spectrum preprocessing was given combining spectrum continuum processing and Fast Fourier Transform (CFFT). Continuum was firstly removed from the noise polluted infrared spectrum to standardize hyper-spectra. Then the spectrum was transformed into frequency domain (FD) with fast Fourier transform (FFT), separating noise information from target information After noise eliminating from useful information with a low-pass filter, the filtered FD spectrum was transformed into time domain (TD) with fast Fourier inverse transform. Finally the continuum was recovered to the spectrum, and the filtered infrared spectrum was achieved. Experiment was performed for chlorite spectrum in USGS polluted with two kinds of simulated white noise to validate the filtering ability of CFFT by contrast with cubic function of five point (CFFP) in time domain and traditional FFT in frequency domain. A circle of CFFP has limited filtering effect, so it should work much with more circles and consume more time to achieve better filtering result. As for conventional FFT, Gibbs phenomenon has great effect on preprocessing result at edge bands because of special character of rock or mineral spectra, while works well at middle bands. Mean squared error of CFFT is 0. 000 012 336 with cut-off frequency of 150, while that of FFT and CFFP is 0. 000 061 074 with cut-off frequency of 150 and 0.000 022 963 with 150 working circles respectively. Besides the filtering result of CFFT can be improved by adjusting the filter cut-off frequency, and has little effect on working time. The CFFT method overcomes the Gibbs problem of FFT in spectrum filtering, and can be more convenient, dependable, and effective than traditional TD filter methods.
Integrated analysis of error detection and recovery
NASA Technical Reports Server (NTRS)
Shin, K. G.; Lee, Y. H.
1985-01-01
An integrated modeling and analysis of error detection and recovery is presented. When fault latency and/or error latency exist, the system may suffer from multiple faults or error propagations which seriously deteriorate the fault-tolerant capability. Several detection models that enable analysis of the effect of detection mechanisms on the subsequent error handling operations and the overall system reliability were developed. Following detection of the faulty unit and reconfiguration of the system, the contaminated processes or tasks have to be recovered. The strategies of error recovery employed depend on the detection mechanisms and the available redundancy. Several recovery methods including the rollback recovery are considered. The recovery overhead is evaluated as an index of the capabilities of the detection and reconfiguration mechanisms.
Generation of complete source samples from the Slew Survey
NASA Technical Reports Server (NTRS)
Schachter, Jonathan
1992-01-01
The Einstein Slew Survey consists of 819 bright X-ray sources, of which 636 (or 78 percent) are identified with counterparts in standard catalogs. We argue for the importance of bright X-ray surveys, and compare the slew results to the ROSAT all-sky survey. Also, we discuss statistical techniques for minimizing confusion in arcminute error circles in digitized data. We describe the 238 Slew Survey AGN, clusters, and BL Lac objects identified to date and their implications for logN-logS and source evolution studies. Also given is a catalog of 1075 sources detected in the Einstein Imaging Proportional Counter (IPC) Slew Survey of the X-ray sky. Five hundred fifty-four of these sources were not previously known as X-ray sources.
Strudwick, Gillian; Reisdorfer, Emilene; Warnock, Caroline; Kalia, Kamini; Sulkers, Heather; Clark, Carrie; Booth, Richard
In an effort to prevent medication errors, barcode medication administration technology has been implemented in many health care organizations. An integrative review was conducted to understand the effect of barcode medication administration technology on medication errors, and characteristics of use demonstrated by nurses contribute to medication safety. Addressing poor system use may support improved patient safety through the reduction of medication administration errors.
Chemical library subset selection algorithms: a unified derivation using spatial statistics.
Hamprecht, Fred A; Thiel, Walter; van Gunsteren, Wilfred F
2002-01-01
If similar compounds have similar activity, rational subset selection becomes superior to random selection in screening for pharmacological lead discovery programs. Traditional approaches to this experimental design problem fall into two classes: (i) a linear or quadratic response function is assumed (ii) some space filling criterion is optimized. The assumptions underlying the first approach are clear but not always defendable; the second approach yields more intuitive designs but lacks a clear theoretical foundation. We model activity in a bioassay as realization of a stochastic process and use the best linear unbiased estimator to construct spatial sampling designs that optimize the integrated mean square prediction error, the maximum mean square prediction error, or the entropy. We argue that our approach constitutes a unifying framework encompassing most proposed techniques as limiting cases and sheds light on their underlying assumptions. In particular, vector quantization is obtained, in dimensions up to eight, in the limiting case of very smooth response surfaces for the integrated mean square error criterion. Closest packing is obtained for very rough surfaces under the integrated mean square error and entropy criteria. We suggest to use either the integrated mean square prediction error or the entropy as optimization criteria rather than approximations thereof and propose a scheme for direct iterative minimization of the integrated mean square prediction error. Finally, we discuss how the quality of chemical descriptors manifests itself and clarify the assumptions underlying the selection of diverse or representative subsets.
A hint of Poincaré dodecahedral topology in the WMAP first year sky map
NASA Astrophysics Data System (ADS)
Roukema, B. F.; Lew, B.; Cechowska, M.; Marecki, A.; Bajtlik, S.
2004-09-01
It has recently been suggested by Luminet et al. (\\cite{LumNat03}) that the WMAP data are better matched by a geometry in which the topology is that of a Poincaré dodecahedral model and the curvature is ``slightly'' spherical, rather than by an (effectively) infinite flat model. A general back-to-back matched circles analysis by Cornish et al. (\\cite{CSSK03}) for angular radii in the range 25-90 °, using a correlation statistic for signal detection, failed to support this. In this paper, a matched circles analysis specifically designed to detect dodecahedral patterns of matched circles is performed over angular radii in the range 1-40\\ddeg on the one-year WMAP data. Signal detection is attempted via a correlation statistic and an rms difference statistic. Extreme value distributions of these statistics are calculated for one orientation of the 36\\ddeg ``screw motion'' (Clifford translation) when matching circles, for the opposite screw motion, and for a zero (unphysical) rotation. The most correlated circles appear for circle radii of \\alpha =11 ± 1 \\ddeg, for the left-handed screw motion, but not for the right-handed one, nor for the zero rotation. The favoured six dodecahedral face centres in galactic coordinates are (\\lII,\\bII) ≈ (252\\ddeg,+65\\ddeg), (51\\ddeg,+51\\ddeg), (144\\ddeg,+38\\ddeg), (207\\ddeg,+10\\ddeg), (271\\ddeg,+3\\ddeg), (332\\ddeg,+25\\ddeg) and their opposites. The six pairs of circles independently each favour a circle angular radius of 11 ± 1\\ddeg. The temperature fluctuations along the matched circles are plotted and are clearly highly correlated. Whether or not these six circle pairs centred on dodecahedral faces match via a 36\\ddeg rotation only due to unexpected statistical properties of the WMAP ILC map, or whether they match due to global geometry, it is clear that the WMAP ILC map has some unusual statistical properties which mimic a potentially interesting cosmological signal.
NASA Astrophysics Data System (ADS)
Lindegren, Lennart
2012-01-01
The launch of the Hipparcos satellite in 1989 and the Hubble Space Telescope in 1990 revolutionized astrometry. By no means does this imply that not much progress was made in the ground-based techniques used exclusively until then. On the contrary, the 1960s to 1980s saw an intense development of new or highly improved instruments, including photoelectric meridian circles, automated plate measuring machines, and the use of chargecoupled device (CCD) detectors for small-field differential astrometry (for a review of optical astrometry at the time, see Monet 1988). In the radio domain, very long baseline interferometry (VLBI) astrometry already provided an extragalactic reference frame accurate to about 1 milliarcsecond (mas) (Ma et al. 1990). Spectacular improvements were made in terms of accuracy, the faintness of the observed objects, and their numbers. However, there was a widening gulf between small-angle astrometry, where differential techniques could overcome atmospheric effects down to below 1 mas, and large-angle astrometry, where conventional instruments such as meridian circles seemed to have hit a barrier in the underlying systematic errors at about 100 mas. Though very precise, the small-angle measurements were of limited use for the determination of positions and proper motions, due to the lack of suitable reference objects in the small fields, and even for parallaxes the necessary correction for the mean parallax of background stars was highly non-trivial. Linking the optical observations to the accurate VLBI frame also proved extremely difficult.
Steffen, Michael; Curtis, Sean; Kirby, Robert M; Ryan, Jennifer K
2008-01-01
Streamline integration of fields produced by computational fluid mechanics simulations is a commonly used tool for the investigation and analysis of fluid flow phenomena. Integration is often accomplished through the application of ordinary differential equation (ODE) integrators--integrators whose error characteristics are predicated on the smoothness of the field through which the streamline is being integrated--smoothness which is not available at the inter-element level of finite volume and finite element data. Adaptive error control techniques are often used to ameliorate the challenge posed by inter-element discontinuities. As the root of the difficulties is the discontinuous nature of the data, we present a complementary approach of applying smoothness-enhancing accuracy-conserving filters to the data prior to streamline integration. We investigate whether such an approach applied to uniform quadrilateral discontinuous Galerkin (high-order finite volume) data can be used to augment current adaptive error control approaches. We discuss and demonstrate through numerical example the computational trade-offs exhibited when one applies such a strategy.
Incorporating Risk and Indicators into a Water Security Framework
NASA Astrophysics Data System (ADS)
Allen, D. M.; Bakker, K.; Simpson, M. W.; Norman, E.; Dunn, G.
2010-12-01
The concept of water security has received growing attention over the past five years in academic debates and policy circles, particularly with respect to cumulative impacts assessment and watershed management. We propose an integrative definition for water security; one that considers both stressors and impacts (or effects) on hydrological systems. We present a water security assessment framework that considers status and risk indicators for both water quality and quantity as measures of impacts. This assessment framework also integrates the social sciences with natural science, engineering, and public health, providing opportunities to address environmental challenges, including the relationship between water and land use dynamics, the integration of aquatic ecosystem and human health concerns, and the alignment of governance with water management imperatives. We argue that this framework has the potential to advance water science, the contributing disciplines, and water policy and management.
Fermionic localization of the schwarzian theory
Stanford, Douglas; Witten, Edward
2017-10-02
The SYK model is a quantum mechanical model that has been proposed to be holographically dual to a 1 + 1-dimensional model of a quantum black hole. An emergent “gravitational” mode of this model is governed by an unusual action that has been called the Schwarzian action. It governs a reparametrization of a circle. We show that the path integral of the Schwarzian theory is one-loop exact. Here, the argument uses a method of fermionic localization, even though the model itself is purely bosonic.
Jones-Schenk, Jan
2017-02-01
Big data is a big topic in all leadership circles. Leaders in professional development must develop an understanding of what data are available across the organization that can inform effective planning for forecasting. Collaborating with others to integrate data sets can increase the power of prediction. Big data alone is insufficient to make big decisions. Leaders must find ways to access small data and triangulate multiple types of data to ensure the best decision making. J Contin Educ Nurs. 2017;48(2):60-61. Copyright 2017, SLACK Incorporated.
Slavnov and Gaudin-Korepin Formulas for Models without U(1) Symmetry: the Twisted XXX Chain
NASA Astrophysics Data System (ADS)
Belliard, Samuel; Pimenta, Rodrigo A.
2015-12-01
We consider the XXX spin-1/2 Heisenberg chain on the circle with an arbitrary twist. We characterize its spectral problem using the modified algebraic Bethe anstaz and study the scalar product between the Bethe vector and its dual. We obtain modified Slavnov and Gaudin-Korepin formulas for the model. Thus we provide a first example of such formulas for quantum integrable models without U(1) symmetry characterized by an inhomogenous Baxter T-Q equation.
Wave Chaos and HPM Effects on Electronic Systems
2013-08-13
if one examines these pas- sages, one will find that, as the orbit length approaches infinity, (i) the fraction of time spent by the orbit in the...as the orbits in a complete quarter circle billiard having the same radius R (see Fig. 3.2(a)). These orbits are tangent to a circular caustic 62 with...a radius Cr. If the caustic radius Cr > ρ0, (see Fig. 3.1) this orbit is trapped in the cap, and is integrable. There are also chaotic orbits that
Models to support students’ understanding of measuring area of circles
NASA Astrophysics Data System (ADS)
Rejeki, S.; Putri, R. I. I.
2018-01-01
Many studies showed that enormous students got confused about the concepts of measuring area of circles. The main reason is because mathematics classroom practices emphasized on memorizing formulas rather than understanding concepts. Therefore, in this study, a set of learning activities were designed as an innovation in learning area measurement of circles. The activities involved two models namely grid paper and reshaping which are respectively as a means and a strategy to support students’ learning of area measurement of circles. Design research was used as the research approach to achieve the aim. Thirty-eight of 8th graders in Indonesia were involved in this study. In this study, together with the contextual problems, the grid paper and reshaping sectors, which used as the models in this learning, helped the students to gradually develop their understanding of the area measurement of circles. The grid papers plays important role in comparing and estimating areas. Whereas, the reshaping sectors might support students’ understanding of the circumference and the area measurement of circles. Those two models could be the tool for promoting the informal theory of area measurement. Besides, the whole activities gave important role on distinguishing the area and perimeter of circles.
NASA Astrophysics Data System (ADS)
Sigurdardottir, Dorotea H.; Stearns, Jett; Glisic, Branko
2017-07-01
The deformed shape is a consequence of loading the structure and it is defined by the shape of the centroid line of the beam after deformation. The deformed shape is a universal parameter of beam-like structures. It is correlated with the curvature of the cross-section; therefore, any unusual behavior that affects the curvature is reflected through the deformed shape. Excessive deformations cause user discomfort, damage to adjacent structural members, and may ultimately lead to issues in structural safety. However, direct long-term monitoring of the deformed shape in real-life settings is challenging, and an alternative is indirect determination of the deformed shape based on curvature monitoring. The challenge of the latter is an accurate evaluation of error in the deformed shape determination, which is directly correlated with the number of sensors needed to achieve the desired accuracy. The aim of this paper is to study the deformed shape evaluated by numerical double integration of the monitored curvature distribution along the beam, and create a method to predict the associated errors and suggest the number of sensors needed to achieve the desired accuracy. The error due to the accuracy in the curvature measurement is evaluated within the scope of this work. Additionally, the error due to the numerical integration is evaluated. This error depends on the load case (i.e., the shape of the curvature diagram), the magnitude of curvature, and the density of the sensor network. The method is tested on a laboratory specimen and a real structure. In a laboratory setting, the double integration is in excellent agreement with the beam theory solution which was within the predicted error limits of the numerical integration. Consistent results are also achieved on a real structure—Streicker Bridge on Princeton University campus.
Quality Circles: A Corporate Strategy Applied in a Student Services Setting.
ERIC Educational Resources Information Center
Steele, Brenton H.; And Others
1987-01-01
Discusses the historical and conceptual framework of quality circles, presents a brief case history of circles initiated by the University of Maryland Office of Admissions, and provides a summary of implications. Emphasizes implications for student affairs administrators. (Author/ABB)
Wind Factor Simulation Model: User’s Manual.
1980-04-01
computer program documentation; com- puterized simulation; equivalent headwind technique; great circle; great circle distance; great circle equation ; great... equation of a great circle. Program listing and flow chart are included. iv UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE(WIh.n Date EnItrd) USER’S...THE EQUATOR . 336 C 337 NTRIFG = 0 338 C 339 C END OF FUNCTION ICONV I 1. RETURN TO MAIN PROGRAM . 340 C 42 341 RETURN 34? C 343 C 344 C 345 C * PART II
Soares, Marcelo B.; Efstratiadis, Argiris
1997-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.
Soares, M.B.; Efstratiadis, A.
1997-06-10
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3{prime} noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.
NASA Astrophysics Data System (ADS)
Indriani, Novi; Julie, Hongki
2017-08-01
According Nuranisa, the students' difficulties on a lesson about the circumference of a circle were to understand the concept of what was the circumference of a circle and solve problems associated with the circumference of a circle [8]. According Nuranisa, this is because the teacher only gives a formula to find the circumference of a circle without helping students to construct the formula [8]. The purposes of this study were (1) to develop the hypothetical learning trajectory (HLT) for the cycle circumference material, (2) to describe the student results from the HLT implementation. The type of research used in this research was the design research developed by Gravemeijer and Cobb (2006). According Gravemeijer and Cobb, the design research was divided into three stages: (1) preparing for the experiment, (2) design experiments, and (3) retrospective analysis [6]. In this study, researchers developed the student learning trajectories which were help students to construct their knowledge about the understanding and how to calculate the circumference of a circle. The context used on the students' learning trajectory was sports and arts event. The learning trajectory has been tried out for 15 grade five students on the Budya Wacana elementary school in Yogyakarta. In this paper, researchers would describe how the learning trajectory traversed students to construct their knowledge about the understanding and how to calculate the circumference of the circle and the student thinking process on the understanding and how to calculate the circumference of a circle. The results showed that students could construct about the understanding of the circumference of a circle and how to calculate the circumference of a circle through the student learning trajectory.
Limitations of the paraxial Debye approximation.
Sheppard, Colin J R
2013-04-01
In the paraxial form of the Debye integral for focusing, higher order defocus terms are ignored, which can result in errors in dealing with aberrations, even for low numerical aperture. These errors can be avoided by using a different integration variable. The aberrations of a glass slab, such as a coverslip, are expanded in terms of the new variable, and expressed in terms of Zernike polynomials to assist with aberration balancing. Tube length error is also discussed.
The experience of meaning in circle dance
Borges da Costa, Ana L.; Cox, Diane L.
2016-01-01
ABSTRACT Circle dance, which derives from the tradition of folk dances, is practised worldwide. This article explores the meanings participants attribute to it. In-depth interviews with 39 participants, teachers and coordinators of teacher training programmes from the circle dance network in the United Kingdom were undertaken. Applying a constructivist grounded theory approach, major categories, representing respectively the experiences of circle dance participants, teachers and coordinators, were developed. This article specifically focuses on the first major category, termed “I can't imagine life without it”, which relates to the experience of 22 dancers. From an occupational perspective, the study reveals how participants realise a sense of meaning and satisfaction through engagement in circle dance and the potential contribution of this occupation to well-being. PMID:27366111
Vicious Circles in Organizations.
ERIC Educational Resources Information Center
Masuch, Michael
1985-01-01
After examining some elementary notions of action theory and cybernetics, this article analyzes the dynamics, clustering, and survival chances of vicious circles. It argues that the action perspective implies that many structural suboptimalities of organizations are caused by vicious circles. Eleven figures and 105 references are provided. (DCS)
VIEW FROM EAST SIDE OF ELM DRIVE/BIRCH CIRCLE BLOCK, SHOWING ...
VIEW FROM EAST SIDE OF ELM DRIVE/BIRCH CIRCLE BLOCK, SHOWING SLOPING TOPOGRAPHY. VIEW FACING WEST. - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI
Wong, Josephine Pui; Li, Alan Tai
2015-01-01
The Exclusionary Circle Game was a learning tool developed for an intervention study to address stigma associated with human immunodeficiency virus (HIV) infection and social exclusion. The objectives of The Exclusionary Circle Game were to enhance collective resonance and empathy, promote critical reflection and dialogue, and motivate collective action to address social exclusion. The game began with all participants being inside a circle. Each participant was randomly given one color-coded card. Each card color represented a character with a specific lived experience associated with racism, patriarchy, homophobia, transphobia, HIV stigma, and so on. Participants holding a marginalized status card were asked to leave the circle in sequence and go to designated spaces. Eventually, only one half of the participants were left in the circle. Participants then debriefed about their experiences within the entire group. The game has been used, beyond the intervention study, at research conferences with positive feedback. In this article, we detail the processes, strengths, and possibility of using this game for empowerment education.
Designing worked examples for learning tangent lines to circles
NASA Astrophysics Data System (ADS)
Retnowati, E.; Marissa
2018-03-01
Geometry is a branch of mathematics that deals with shape and space, including the circle. A difficult topic in the circle may be the tangent line to circle. This is considered a complex material since students have to simultaneously apply several principles to solve the problems, these are the property of circle, definition of the tangent, measurement and Pythagorean theorem. This paper discusses designs of worked examples for learning tangent line to circles and how to apply this design to an effective and efficient instructional activity. When students do not have sufficient prior knowledge, solving tangent problems might be clumsy, and as a consequence, the problem-solving activity hinders learning. According to a Cognitive Load Theory, learning occurs when students can construct new knowledge based on the relevant knowledge previously learned. When the relevant knowledge is unavailable, providing students with the worked example is suggested. Worked example may reduce unproductive process during learning that causes extraneous cognitive load. Nevertheless, worked examples must be created in such a way facilitate learning.
NASA Astrophysics Data System (ADS)
Straus, D. M.
2007-12-01
The probability distribution (pdf) of errors is followed in identical twin studies using the COLA T63 AGCM, integrated with observed SST for 15 recent winters. 30 integrations per winter (for 15 winters) are available with initial errors that are extremely small. The evolution of the pdf is tested for multi-modality, and the results interpreted in terms of clusters / regimes found in: (a) the set of 15x30 integrations mentioned, and (b) a larger ensemble of 55x15 integrations made with the same GCM using the same SSTs. The mapping of pdf evolution and clusters is also carried out for each winter separately, using the clusters found in the 55-member ensemble for the same winter alone. This technique yields information on the change in regimes caused by different boundary forcing (Straus and Molteni, 2004; Straus, Corti and Molteni, 2006). Analysis of the growing errors in terms of baroclinic and barotropic components allows for interpretation of the corresponding instabilities.
Comfortable synchronization of cyclic drawing movements with a metronome.
Repp, Bruno H
2011-02-01
Continuous circle drawing is considered a paragon of emergent timing, whereas the timing of finger tapping is said to be event-based. Synchronization with a metronome, however, must to some extent be event-based for both types of movement. Because the target events in the movement trajectory are more poorly defined in circle drawing than in tapping, circle drawing shows more variable asynchronies with a metronome than does tapping. One factor that may have contributed to high variability in past studies is that circle size, drawing direction, and target point were prescribed and perhaps outside the comfort range. In the present study, participants were free to choose most comfortable settings of these parameters for two continuously drawn shapes, circles and infinity signs, while synchronizing with a regular or intermittently perturbed metronome at four different tempi. Results showed that preferred circle sizes were generally smaller than in previous studies but tended to increase as tempo decreased. Synchronization results were similar for circles and infinity signs, and similar to earlier results for circles drawn within a fixed template (Repp & Steinman, 2010). Comparison with tapping data still showed drawing to exhibit much greater variability and persistence of asynchronies as well as slower phase correction in response to phase shifts in the metronome. With comfort level ruled out as a factor, these differences can now be attributed more confidently to differences in event definition and/or movement dynamics. Copyright © 2010 Elsevier B.V. All rights reserved.
Leduc, Renee Y M; Rauw, Gail; Baker, Glen B; McDermid, Heather E
2017-01-01
Environmental enrichment items such as running wheels can promote the wellbeing of laboratory mice. Growing evidence suggests that wheel running simulates exercise effects in many mouse models of human conditions, but this activity also might change other aspects of mouse behavior. In this case study, we show that the presence of running wheels leads to pronounced and permanent circling behavior with route-tracing in a proportion of the male mice of a genetically distinct cohort. The genetic background of this cohort includes a mutation in Arhgap19, but genetic crosses showed that an unknown second-site mutation likely caused the induced circling behavior. Behavioral tests for inner-ear function indicated a normal sense of gravity in the circling mice. However, the levels of dopamine, serotonin, and some dopamine metabolites were lower in the brains of circling male mice than in mice of the same genetic background that were weaned without wheels. Circling was seen in both singly and socially housed male mice. The additional stress of fighting may have exacerbated the predisposition to circling in the socially housed animals. Singly and socially housed male mice without wheels did not circle. Our current findings highlight the importance and possibly confounding nature of the environmental and genetic background in mouse behavioral studies, given that the circling behavior and alterations in dopamine and serotonin levels in this mouse cohort occurred only when the male mice were housed with running wheels. PMID:28315651
Gated integrator with signal baseline subtraction
Wang, X.
1996-12-17
An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window. 5 figs.
Gated integrator with signal baseline subtraction
Wang, Xucheng
1996-01-01
An ultrafast, high precision gated integrator includes an opamp having differential inputs. A signal to be integrated is applied to one of the differential inputs through a first input network, and a signal indicative of the DC offset component of the signal to be integrated is applied to the other of the differential inputs through a second input network. A pair of electronic switches in the first and second input networks define an integrating period when they are closed. The first and second input networks are substantially symmetrically constructed of matched components so that error components introduced by the electronic switches appear symmetrically in both input circuits and, hence, are nullified by the common mode rejection of the integrating opamp. The signal indicative of the DC offset component is provided by a sample and hold circuit actuated as the integrating period begins. The symmetrical configuration of the integrating circuit improves accuracy and speed by balancing out common mode errors, by permitting the use of high speed switching elements and high speed opamps and by permitting the use of a small integrating time constant. The sample and hold circuit substantially eliminates the error caused by the input signal baseline offset during a single integrating window.
Comprehensibility of Englishes within ASEAN: A Synopsis of Results
ERIC Educational Resources Information Center
Wilang, Jeffrey Dawala; Teo, Adisa
2012-01-01
The purpose of this study is to measure the comprehensibility of the Expanding Circle nations' citizens, namely Burmese, Cambodians, Indonesians, Laotians, Thais and Vietnamese towards the Outer Circle Englishes, namely Bruneian English, Malaysian English. Philippine English and Singaporean English. Ten universities in the Expanding Circle that…
A Comprehensive Analysis of Uncertainties Affecting the Stellar Mass-Halo Mass Relation for 0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Behroozi, Peter S.; Conroy, Charlie; Wechsler, Risa H.
2010-06-07
We conduct a comprehensive analysis of the relationship between central galaxies and their host dark matter halos, as characterized by the stellar mass - halo mass (SM-HM) relation, with rigorous consideration of uncertainties. Our analysis focuses on results from the abundance matching technique, which assumes that every dark matter halo or subhalo above a specific mass threshold hosts one galaxy. We provide a robust estimate of the SM-HM relation for 0 < z < 1 and discuss the quantitative effects of uncertainties in observed galaxy stellar mass functions (GSMFs) (including stellar mass estimates and counting uncertainties), halo mass functions (includingmore » cosmology and uncertainties from substructure), and the abundance matching technique used to link galaxies to halos (including scatter in this connection). Our analysis results in a robust estimate of the SM-HM relation and its evolution from z=0 to z=4. The shape and evolution are well constrained for z < 1. The largest uncertainties at these redshifts are due to stellar mass estimates (0.25 dex uncertainty in normalization); however, failure to account for scatter in stellar masses at fixed halo mass can lead to errors of similar magnitude in the SM-HM relation for central galaxies in massive halos. We also investigate the SM-HM relation to z = 4, although the shape of the relation at higher redshifts remains fairly unconstrained when uncertainties are taken into account. We find that the integrated star formation at a given halo mass peaks at 10-20% of available baryons for all redshifts from 0 to 4. This peak occurs at a halo mass of 7 x 10{sup 11} M{sub {circle_dot}} at z = 0 and this mass increases by a factor of 5 to z = 4. At lower and higher masses, star formation is substantially less efficient, with stellar mass scaling as M{sub *} {approx} M{sub h}{sup 2.3} at low masses and M{sub *} {approx} M{sub h}{sup 0.29} at high masses. The typical stellar mass for halos with mass less than 10{sup 12} M{sub {circle_dot}} has increased by 0.3-0.45 dex for halos since z {approx} 1. These results will provide a powerful tool to inform galaxy evolution models.« less
Andersson, Cecilia; Henriksson, Sara; Magnusson, Karl-Eric; Nilsson, Mats; Mirazimi, Ali
2012-05-10
Crimean Congo hemorrhagic fever virus (CCHFV) is a human pathogen that causes a severe disease with high fatality rate for which there is currently no specific treatment. Knowledge regarding its replication cycle is also highly limited. In this study we developed an in situ technique for studying the different stages during the replication of CCHFV. By integrating reverse transcription, padlock probes, and rolling circle amplification, we were able to detect and differentiate between viral RNA (vRNA) and complementary RNA (cRNA) molecules, and to detect viral protein within the same cell. These data demonstrate that CCHFV nucleocapsid protein (NP) is detectable already at 6 hours post infection in vRNA- and cRNA-positive cells. Confocal microscopy showed that cRNA is enriched and co-localized to a large extent with NP in the perinuclear area, while vRNA has a more random distribution in the cytoplasm with only some co-localize with NP. However, vRNA and cRNA did not appear to co-localize directly. Copyright © 2012 Elsevier Inc. All rights reserved.
RTEL1 dismantles T loops and counteracts telomeric G4-DNA to maintain telomere integrity.
Vannier, Jean-Baptiste; Pavicic-Kaltenbrunner, Visnja; Petalcorin, Mark I R; Ding, Hao; Boulton, Simon J
2012-05-11
T loops and telomeric G-quadruplex (G4) DNA structures pose a potential threat to genome stability and must be dismantled to permit efficient telomere replication. Here we implicate the helicase RTEL1 in the removal of telomeric DNA secondary structures, which is essential for preventing telomere fragility and loss. In the absence of RTEL1, T loops are inappropriately resolved by the SLX4 nuclease complex, resulting in loss of the telomere as a circle. Depleting SLX4 or blocking DNA replication abolished telomere circles (TCs) and rescued telomere loss in RTEL1(-/-) cells but failed to suppress telomere fragility. Conversely, stabilization of telomeric G4-DNA or loss of BLM dramatically enhanced telomere fragility in RTEL1-deficient cells but had no impact on TC formation or telomere loss. We propose that RTEL1 performs two distinct functions at telomeres: it disassembles T loops and also counteracts telomeric G4-DNA structures, which together ensure the dynamics and stability of the telomere. Copyright © 2012 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Podio, Fernando; Vollrath, William; Williams, Joel; Kobler, Ben; Crouse, Don
1998-01-01
Sophisticated network storage management applications are rapidly evolving to satisfy a market demand for highly reliable data storage systems with large data storage capacities and performance requirements. To preserve a high degree of data integrity, these applications must rely on intelligent data storage devices that can provide reliable indicators of data degradation. Error correction activity generally occurs within storage devices without notification to the host. Early indicators of degradation and media error monitoring 333 and reporting (MEMR) techniques implemented in data storage devices allow network storage management applications to notify system administrators of these events and to take appropriate corrective actions before catastrophic errors occur. Although MEMR techniques have been implemented in data storage devices for many years, until 1996 no MEMR standards existed. In 1996 the American National Standards Institute (ANSI) approved the only known (world-wide) industry standard specifying MEMR techniques to verify stored data on optical disks. This industry standard was developed under the auspices of the Association for Information and Image Management (AIIM). A recently formed AIIM Optical Tape Subcommittee initiated the development of another data integrity standard specifying a set of media error monitoring tools and media error monitoring information (MEMRI) to verify stored data on optical tape media. This paper discusses the need for intelligent storage devices that can provide data integrity metadata, the content of the existing data integrity standard for optical disks, and the content of the MEMRI standard being developed by the AIIM Optical Tape Subcommittee.
Wheel speed management control system for spacecraft
NASA Technical Reports Server (NTRS)
Goodzeit, Neil E. (Inventor); Linder, David M. (Inventor)
1991-01-01
A spacecraft attitude control system uses at least four reaction wheels. In order to minimize reaction wheel speed and therefore power, a wheel speed management system is provided. The management system monitors the wheel speeds and generates a wheel speed error vector. The error vector is integrated, and the error vector and its integral are combined to form a correction vector. The correction vector is summed with the attitude control torque command signals for driving the reaction wheels.
Conceptions and Representations: The Circle as an Example.
ERIC Educational Resources Information Center
Janvier, Claude
This paper, which addresses the issue of representation as an internal construct corresponding to an external abstract configuration, attempts to extend A. A. DiSessa's phenomenological primitives to mathematics (particularly to the notion of circle). Various acceptations of the word representation are examined, using the notion of a circle as an…
Exploring Writing Circles as Innovative, Collaborative Writing Structures with Teacher Candidates
ERIC Educational Resources Information Center
Roberts, Sherron Killingsworth; Blanch, Norine; Gurjar, Nandita
2017-01-01
Writing circles are "small groups... meeting regularly to share drafts, choose common writing topics, practice positive response, and in general, help each other become better writers" (Vopat, 2009, p. 6). In this exploratory study, writing circles were employed with elementary teacher candidates in hopes of enhancing their perceptions…
The Effect of Literature Circles on Text Analysis and Reading Desire
ERIC Educational Resources Information Center
Karatay, Halit
2017-01-01
In order to make teaching activities more appealing, different techniques and strategies have been constantly employed. This study utilized the strategy of "literature circles" to improve the text-analysis skills, reading desires, and interests of prospective teachers of Turkish. "Literature circles" was not chosen to be used…
Adjusting an electron beam for drilling
NASA Technical Reports Server (NTRS)
Childress, C. L.
1980-01-01
Reticle contains two concentric circles: inner circle insures beam circularity and outer circle is guide to prevent beam from cutting workpiece clamp. Precise measurement of beam and clamp are required with old reticle. New reticle speeds up electron-beam drilling process by eliminating need to rotate eyepiece to make measurements against reticle scale.
Participation and Gender in Circle-Time Situations in Preschool
ERIC Educational Resources Information Center
Emilson, Anette; Johansson, Eva
2013-01-01
This study sought to investigate participatory values in relation to gender, as expressed in interactions between teachers and children in circle-time situations in Swedish and Norwegian preschools. This paper reports evidence from three research questions: How is children's participation conditioned in circle-time situations? How are…
An Effective Time and Management Strategy in Quality Circles.
ERIC Educational Resources Information Center
Halverson, Don E.
Contending that participation in quality circles enhances effective time management by school administrators and teachers, this guide provides both a theoretical briefing and practical recommendations for better time management. A pre- posttest prefaces a review of basic concepts of quality circles with reference to the work of Abraham Maslow,…
Quality Circles in Higher Education: Quality, Satisfaction, and Climate.
ERIC Educational Resources Information Center
Kay, Carol; Healy, Margaret
The effect of quality circles at Iowa State University on absenteeism, performance evaluation, perceptions of the organization climate, job satisfaction, and perceived opportunities for professional and personal growth was measured in this study. The process of quality circles is designed to promote job fulfillment and organizational productivity…
VIEW OF THE OUTER RING OF CENTER CIRCLE, LOOKING NORTH. ...
VIEW OF THE OUTER RING OF CENTER CIRCLE, LOOKING NORTH. GRANITE COPING DEFINES THE SWAIN FAMILY PLOT, WHICH CONTAINS A CELTIC CROSS, ON WHICH THE CIRCLE REFERS TO ETERNAL LIFE, AND A RECLINING HUMAN FIGURE IN ETERNAL SLEEP - Woodlands Cemetery, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA
Using Literature Circles to Enhance Student Knowledge of Nonfiction Text
ERIC Educational Resources Information Center
Whitworth, Amanda
2017-01-01
This mixed methods action research study explored how students reacted to using literature circles to enhance their knowledge and understanding of reading nonfiction text as compared to students using guided reading. This study showed a minimal improvement for students participating in the literature circle group in overall understanding of…
Assign Roles to Get Literature Circles Rolling
ERIC Educational Resources Information Center
Curriculum Review, 2005
2005-01-01
This article briefly describes a role-playing exercise designed to break the ice in a classroom literature circle from The Ultimate Small-Group Reading How-To Book: Building Comprehension through SmallGroup Instruction, written by Gail Saunders-Smith. The members of a literature circle participate in the group discussion according to the…
Literature Circles. ERIC Digest.
ERIC Educational Resources Information Center
Lin, Chia-Hui
The use of literature circles has been discussed in a variety of academic journals, conference papers, and workshops. Teachers at all grade levels use literature circles as a vehicle through which students learn to: think critically about literature; express their thoughts in oral and written forms; and better enjoy their literacy experiences.…
Developing Soft Skills Using "Literature Circles"
ERIC Educational Resources Information Center
Azmi, Mohd Nazri Bin Latiff
2013-01-01
This study investigates the impact of the implementation of "Literature Circles" in an Active Learning classroom in relations to developing soft skills among university students. The use of Literature Circles is a well-known strategy in teaching the students to be more creative, independent, and think out of the box. A group of…
Exploring Factors That Influence Quality Literature Circles
ERIC Educational Resources Information Center
Young, Chase; Mohr, Kathleen A. J.
2018-01-01
Research indicates that literature circles are an authentic means for literacy development that students typically enjoy. To better understand the potential value and to add to the research base regarding literature circles, this study, involving 17 fourth graders, explores factors that may influence the quality of literature discussions,…
Method for construction of normalized cDNA libraries
Soares, Marcelo B.; Efstratiadis, Argiris
1996-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.
Method for construction of normalized cDNA libraries
Soares, M.B.; Efstratiadis, A.
1996-01-09
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form. The method comprises: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.
Sister Circles as a Culturally Relevant Intervention for Anxious African American Women
Neal-Barnett, Angela; Stadulis, Robert; Murray, Marsheena; Payne, Margaret Ralston; Thomas, Anisha; Salley, Bernadette B.
2011-01-01
Research on anxiety treatment with African American women reveals a need to develop interventions that address factors relevant to their lives. Such factors include feelings of isolation, multiple roles undertaken by Black women, and faith. A recurrent theme across treatment studies is the importance of having support from other Black women. Sister circles are support groups that build upon existing friendships, fictive kin networks, and the sense of community found among African Americans females. Sister circles appear to offer many of the components Black women desire in an anxiety intervention. In this article, we explore sister circles as an intervention for anxious African American women. Culturally-infused aspects from our sister circle work with middle-class African American women are presented. Further research is needed. PMID:22081747
Merrill, Edward C; Conners, Frances A
2013-08-01
We evaluated age-related variations in the influence of heterogeneous distracters during feature target. Participants in three age groups-6-year-old children, 9-year-old children, and young adults-completed three conditions of search. In a singleton search condition, participants searched for a circle among squares of the same color. In two feature mode search conditions, participants searched for a gray circle or a black circle among gray and black squares. Singleton search was performed at the same level of efficiency for all age groups. In contrast, the two feature mode search conditions yielded age-related performance differences in both conditions. Younger children exhibited a steeper slope than young adults when searching for a gray or black circle. Older children exhibited a steeper slope than young adults when searching for a gray circle but not when searching for a black circle. We concluded that these differences revealed age-related improvements in the relative abilities of adults and children to execute attentional control processes during visual search. In particular, it appears that children found it more difficult to maintain the goal of searching for a circle target than adults and were distracted by the presence of the irrelevant feature dimension of color. Published by Elsevier Inc.
Method to manage integration error in the Green-Kubo method.
Oliveira, Laura de Sousa; Greaney, P Alex
2017-02-01
The Green-Kubo method is a commonly used approach for predicting transport properties in a system from equilibrium molecular dynamics simulations. The approach is founded on the fluctuation dissipation theorem and relates the property of interest to the lifetime of fluctuations in its thermodynamic driving potential. For heat transport, the lattice thermal conductivity is related to the integral of the autocorrelation of the instantaneous heat flux. A principal source of error in these calculations is that the autocorrelation function requires a long averaging time to reduce remnant noise. Integrating the noise in the tail of the autocorrelation function becomes conflated with physically important slow relaxation processes. In this paper we present a method to quantify the uncertainty on transport properties computed using the Green-Kubo formulation based on recognizing that the integrated noise is a random walk, with a growing envelope of uncertainty. By characterizing the noise we can choose integration conditions to best trade off systematic truncation error with unbiased integration noise, to minimize uncertainty for a given allocation of computational resources.
Integrator Windup Protection-Techniques and a STOVL Aircraft Engine Controller Application
NASA Technical Reports Server (NTRS)
KrishnaKumar, K.; Narayanaswamy, S.
1997-01-01
Integrators are included in the feedback loop of a control system to eliminate the steady state errors in the commanded variables. The integrator windup problem arises if the control actuators encounter operational limits before the steady state errors are driven to zero by the integrator. The typical effects of windup are large system oscillations, high steady state error, and a delayed system response following the windup. In this study, methods to prevent the integrator windup are examined to provide Integrator Windup Protection (IW) for an engine controller of a Short Take-Off and Vertical Landing (STOVL) aircraft. An unified performance index is defined to optimize the performance of the Conventional Anti-Windup (CAW) and the Modified Anti-Windup (MAW) methods. A modified Genetic Algorithm search procedure with stochastic parameter encoding is implemented to obtain the optimal parameters of the CAW scheme. The advantages and drawbacks of the CAW and MAW techniques are discussed and recommendations are made for the choice of the IWP scheme, given some characteristics of the system.
Method to manage integration error in the Green-Kubo method
NASA Astrophysics Data System (ADS)
Oliveira, Laura de Sousa; Greaney, P. Alex
2017-02-01
The Green-Kubo method is a commonly used approach for predicting transport properties in a system from equilibrium molecular dynamics simulations. The approach is founded on the fluctuation dissipation theorem and relates the property of interest to the lifetime of fluctuations in its thermodynamic driving potential. For heat transport, the lattice thermal conductivity is related to the integral of the autocorrelation of the instantaneous heat flux. A principal source of error in these calculations is that the autocorrelation function requires a long averaging time to reduce remnant noise. Integrating the noise in the tail of the autocorrelation function becomes conflated with physically important slow relaxation processes. In this paper we present a method to quantify the uncertainty on transport properties computed using the Green-Kubo formulation based on recognizing that the integrated noise is a random walk, with a growing envelope of uncertainty. By characterizing the noise we can choose integration conditions to best trade off systematic truncation error with unbiased integration noise, to minimize uncertainty for a given allocation of computational resources.
Wang, Shu-mei; Liu, Jun-xin
2005-01-01
Compared to conventional oxidation ditches, an integrated oxidation ditch with vertical circle (IODVC) has the characters of concise configuration, simple operation and maintenance, land saving and automatical sludge returning. By the utilization of vertical circulation, an aerobic zone and an anoxic zone can be unaffectedly formed in the IODVC. Therefore, COD and nitrogen can be efficiently removed. However, the removal efficiency of phosphorus was low in the IODVC. In the experiment described, a laboratory scale system to add an anaerobic column to the IODVC has been tested to investigate the removal of phosphorus from wastewater. The experimental results showed that the removal efficiency of TP with the anaerobic column was increased to 54.0% from 22.3% without the anaerobic column. After the acetic sodium was added into the influent as carbon sources, the mean TP removal efficency of 77.5% was obtained. At the same time, the mean removal efficiencies of COD, TN and NH3-N were 92.2%, 81.6% and 98.1%, respectively, at 12 h of HRT and 21-25 d of SRT. The optimal operational conditions in this study were as follows: recycle rate = 1.5-2.0, COD/TN > 6, COD/TP > 40, COD loading rate = 0.26-0.32 kgCOD/(kgSS x d), TN loading rate = 0.028-0.034 kgTN/(kgSS x d) and TP loading rate = 0.003-0.005 kgTP/(kgSS x d), respectively.
Analysis of all-optical temporal integrator employing phased-shifted DFB-SOA.
Jia, Xin-Hong; Ji, Xiao-Ling; Xu, Cong; Wang, Zi-Nan; Zhang, Wei-Li
2014-11-17
All-optical temporal integrator using phase-shifted distributed-feedback semiconductor optical amplifier (DFB-SOA) is investigated. The influences of system parameters on its energy transmittance and integration error are explored in detail. The numerical analysis shows that, enhanced energy transmittance and integration time window can be simultaneously achieved by increased injected current in the vicinity of lasing threshold. We find that the range of input pulse-width with lower integration error is highly sensitive to the injected optical power, due to gain saturation and induced detuning deviation mechanism. The initial frequency detuning should also be carefully chosen to suppress the integration deviation with ideal waveform output.
NASA Technical Reports Server (NTRS)
Vess, Melissa F.; Starin, Scott R.
2007-01-01
During design of the SDO Science and Inertial mode PID controllers, the decision was made to disable the integral torque whenever system stability was in question. Three different schemes were developed to determine when to disable or enable the integral torque, and a trade study was performed to determine which scheme to implement. The trade study compared complexity of the control logic, risk of not reenabling the integral gain in time to reject steady-state error, and the amount of integral torque space used. The first scheme calculated a simplified Routh criterion to determine when to disable the integral torque. The second scheme calculates the PD part of the torque and looked to see if that torque would cause actuator saturation. If so, only the PD torque is used. If not, the integral torque is added. Finally, the third scheme compares the attitude and rate errors to limits and disables the integral torque if either of the errors is greater than the limit. Based on the trade study results, the third scheme was selected. Once it was decided when to disable the integral torque, analysis was performed to determine how to disable the integral torque and whether or not to reset the integrator once the integral torque was reenabled. Three ways to disable the integral torque were investigated: zero the input into the integrator, which causes the integral part of the PID control torque to be held constant; zero the integral torque directly but allow the integrator to continue integrating; or zero the integral torque directly and reset the integrator on integral torque reactivation. The analysis looked at complexity of the control logic, slew time plus settling time between each calibration maneuver step, and ability to reject steady-state error. Based on the results of the analysis, the decision was made to zero the input into the integrator without resetting it. Throughout the analysis, a high fidelity simulation was used to test the various implementation methods.
THE FORM AND STRUCTURE OF KINETOPLAST DNA OF CRITHIDIA
Renger, Hartmut C.; Wolstenholme, David R.
1972-01-01
Cesium chloride centrifugation of each of the DNAs extracted from eight strains of Crithidia revealed a main band at ρ = 1.717 g/cm3 and a satellite band varying from ρ = 1.701 to 1.705 g/cm3 for the different strains By electron microscopy each DNA was shown to include circular molecules, 0.69–0.80 µ in mean contour length, and large, topologically two-dimensional masses of DNA in which the molecules appeared in the form of rosettes. DNA isolated from kinetoplast fractions of Crithidia acanthocephali was shown to consist of light satellite DNA and to be mainly in the form of large masses, 0.8 µ (mol wt = 1.54 x 106 daltons) circular molecules, and a few long, linear molecules. The results of experiments involving ultracentrifugation, heating, and quenching, sonication, and endodeoxyribonuclease digestion, combined with electron microscopy, are consistent with the following hypothesis. The large DNA masses are associations of 0.8 µ circles which are mainly covalently closed. The circles are held together in groups (the rosettes) of up to 46 by the topological interlocking of each circle with many other circles in the group. A group of circles is attached to an adjacent group by one or more circles, each interlocking with many circles of both groups. Each of the associations comprises, on the average, about 27,000 circles (total mol wt ≃ 41 x 109 daltons). A model is proposed for the in situ arrangement of the associations which takes into consideration their form and structure, and appearance in thin sections PMID:5040863
Ning, Ruola; Tang, Xiangyang; Conover, David; Yu, Rongfeng
2003-07-01
Cone beam computed tomography (CBCT) has been investigated in the past two decades due to its potential advantages over a fan beam CT. These advantages include (a) great improvement in data acquisition efficiency, spatial resolution, and spatial resolution uniformity, (b) substantially better utilization of x-ray photons generated by the x-ray tube compared to a fan beam CT, and (c) significant advancement in clinical three-dimensional (3D) CT applications. However, most studies of CBCT in the past are focused on cone beam data acquisition theories and reconstruction algorithms. The recent development of x-ray flat panel detectors (FPD) has made CBCT imaging feasible and practical. This paper reports a newly built flat panel detector-based CBCT prototype scanner and presents the results of the preliminary evaluation of the prototype through a phantom study. The prototype consisted of an x-ray tube, a flat panel detector, a GE 8800 CT gantry, a patient table and a computer system. The prototype was constructed by modifying a GE 8800 CT gantry such that both a single-circle cone beam acquisition orbit and a circle-plus-two-arcs orbit can be achieved. With a circle-plus-two-arcs orbit, a complete set of cone beam projection data can be obtained, consisting of a set of circle projections and a set of arc projections. Using the prototype scanner, the set of circle projections were acquired by rotating the x-ray tube and the FPD together on the gantry, and the set of arc projections were obtained by tilting the gantry while the x-ray tube and detector were at the 12 and 6 o'clock positions, respectively. A filtered backprojection exact cone beam reconstruction algorithm based on a circle-plus-two-arcs orbit was used for cone beam reconstruction from both the circle and arc projections. The system was first characterized in terms of the linearity and dynamic range of the detector. Then the uniformity, spatial resolution and low contrast resolution were assessed using different phantoms mainly in the central plane of the cone beam reconstruction. Finally, the reconstruction accuracy of using the circle-plus-two-arcs orbit and its related filtered backprojection cone beam volume CT reconstruction algorithm was evaluated with a specially designed disk phantom. The results obtained using the new cone beam acquisition orbit and the related reconstruction algorithm were compared to those obtained using a single-circle cone beam geometry and Feldkamp's algorithm in terms of reconstruction accuracy. The results of the study demonstrate that the circle-plus-two-arcs cone beam orbit is achievable in practice. Also, the reconstruction accuracy of cone beam reconstruction is significantly improved with the circle-plus-two-arcs orbit and its related exact CB-FPB algorithm, as compared to using a single circle cone beam orbit and Feldkamp's algorithm.
ERIC Educational Resources Information Center
Stephenson, Paul
2009-01-01
In order to find its circumference, Archimedes famously boxed the circle between two polygons. Ending the first of a series of articles (MT179) with an aside, Francis Lopez-Real reverses the situation to ask: Which polygons can be boxed between two circles? (The official term for such polygons is "bicentric".) The sides of these polygons are…
Empowerment of Children through Circle Time: Myth or Reality?
ERIC Educational Resources Information Center
Collins, Bernie
2013-01-01
The focus of this paper is circle time, a widely used method in primary schools in Ireland and elsewhere. It involves children sitting in a circle with their teacher using method-specific techniques and strategies for self-esteem enhancement, promoting positive relationships and development of social skills. Qualitative research was undertaken in…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-23
... ENVIRONMENTAL PROTECTION AGENCY [FRL-9837-3; CERCLA-04-2013-3760] Circle Environmental 1 Superfund... settlement with Walter G. Mercer, Jr. concerning the Circle Environmental 1 Superfund Site located in Dawson... methods: Internet: www.epa.gov/region4/superfund/programs/enforcement/enforcement.html U.S. Mail: U.S...
VIEW OF DATE DRIVE, FROM INTERSECTION WITH BIRCH CIRCLE, WITH ...
VIEW OF DATE DRIVE, FROM INTERSECTION WITH BIRCH CIRCLE, WITH FACILITY 809 ON LEFT, 816 ON RIGHT. NOTE THE MANY DATE PALMS. VIEW FACING NORTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI
From Silence to a Whisper to Active Participation: Using Literature Circles with ELL Students
ERIC Educational Resources Information Center
Carrison, Catherine; Ernst-Slavit, Gisela
2005-01-01
This article discusses benefits of using literature circles with ELL students to strengthen literacy skills and student confidence. Highlighting one teacher's implementation of literature circles, the authors present a candid examination of areas of initial weakness and describe strategies used for improvements in subsequent "rounds." A discussion…
Comparing Interactions in Literature Circles in Both Online and in Class Discussions
ERIC Educational Resources Information Center
Skeen, Christel Ghrist
2014-01-01
Discourse analysis of literature circles can lead educators to understand the different types of interactions taking place as students talk about text. Social and academic interactions exist in both face-to-face and online discussions of reading material. This study examines two different settings of literature circles and compares interactions of…
College Students' Science Societies and Special-Interest Circles
ERIC Educational Resources Information Center
Ivanov, A.
2005-01-01
From the point of view of their age, student science societies and special-interest circles are among the most venerable forms of corporate association among students in colleges and universities. In this article, the author traces the formation of different societies and special-interest circles by college students in different universities in…
Chiang, Kai-Wei; Duong, Thanh Trung; Liao, Jhen-Kai
2013-01-01
The integration of an Inertial Navigation System (INS) and the Global Positioning System (GPS) is common in mobile mapping and navigation applications to seamlessly determine the position, velocity, and orientation of the mobile platform. In most INS/GPS integrated architectures, the GPS is considered to be an accurate reference with which to correct for the systematic errors of the inertial sensors, which are composed of biases, scale factors and drift. However, the GPS receiver may produce abnormal pseudo-range errors mainly caused by ionospheric delay, tropospheric delay and the multipath effect. These errors degrade the overall position accuracy of an integrated system that uses conventional INS/GPS integration strategies such as loosely coupled (LC) and tightly coupled (TC) schemes. Conventional tightly coupled INS/GPS integration schemes apply the Klobuchar model and the Hopfield model to reduce pseudo-range delays caused by ionospheric delay and tropospheric delay, respectively, but do not address the multipath problem. However, the multipath effect (from reflected GPS signals) affects the position error far more significantly in a consumer-grade GPS receiver than in an expensive, geodetic-grade GPS receiver. To avoid this problem, a new integrated INS/GPS architecture is proposed. The proposed method is described and applied in a real-time integrated system with two integration strategies, namely, loosely coupled and tightly coupled schemes, respectively. To verify the effectiveness of the proposed method, field tests with various scenarios are conducted and the results are compared with a reliable reference system. PMID:23955434
Error Reduction Methods for Integrated-path Differential-absorption Lidar Measurements
NASA Technical Reports Server (NTRS)
Chen, Jeffrey R.; Numata, Kenji; Wu, Stewart T.
2012-01-01
We report new modeling and error reduction methods for differential-absorption optical-depth (DAOD) measurements of atmospheric constituents using direct-detection integrated-path differential-absorption lidars. Errors from laser frequency noise are quantified in terms of the line center fluctuation and spectral line shape of the laser pulses, revealing relationships verified experimentally. A significant DAOD bias is removed by introducing a correction factor. Errors from surface height and reflectance variations can be reduced to tolerable levels by incorporating altimetry knowledge and "log after averaging", or by pointing the laser and receiver to a fixed surface spot during each wavelength cycle to shorten the time of "averaging before log".
Yang, Yanqiang; Zhang, Chunxi; Lu, Jiazhen
2017-01-16
Strapdown inertial navigation system/celestial navigation system (SINS/CNS) integrated navigation is a fully autonomous and high precision method, which has been widely used to improve the hitting accuracy and quick reaction capability of near-Earth flight vehicles. The installation errors between SINS and star sensors have been one of the main factors that restrict the actual accuracy of SINS/CNS. In this paper, an integration algorithm based on the star vector observations is derived considering the star sensor installation error. Then, the star sensor installation error is accurately estimated based on Kalman Filtering (KF). Meanwhile, a local observability analysis is performed on the rank of observability matrix obtained via linearization observation equation, and the observable conditions are presented and validated. The number of star vectors should be greater than or equal to 2, and the times of posture adjustment also should be greater than or equal to 2. Simulations indicate that the star sensor installation error could be readily observable based on the maneuvering condition; moreover, the attitude errors of SINS are less than 7 arc-seconds. This analysis method and conclusion are useful in the ballistic trajectory design of near-Earth flight vehicles.
Violence in the eye of adolescents: education intervention with Culture Circles.
Brandão Neto, Waldemar; Silva, Marta Angélica Iossi; de Aquino, Jael Maria; de Lima, Luciane Soares; Monteiro, Estela Maria Leite Meirelles
2015-01-01
to apply the methodology of Culture Circles on adolescents as a strategy for health education of nurses in the construction of the collective knowledge of the thematic violence. action research type and qualitative study. Participants were 11 adolescents from a public school in Recife, PE, Brazil. Data production in Culture Circles included the participant observation with field diary, photographic recording and filming, as well as the photovoice technique. The analysis was performed by triangulating data in dialogue with the literature. it was shown that the problematizing action provided by the Culture Circle made possible to create situations in which adolescents felt invited to critically refl ect on the phenomenon of violence in all its complexity. the health education intervention, performed by Culture Circles, added learning and mutual growth subsidizing nursing care actions that excel at leadership and autonomy of adolescents.
Study on active lap tool influence function in grinding 1.8 m primary mirror.
Haitao, Liu; Zhige, Zeng; Fan, Wu; Bin, Fan; Yongjian, Wan
2013-11-01
We present a theoretical modeling method to predict the ring tool influence function (TIF) based on the computer-controlled active lap process. The gap on the lap-grinding layer is considered, and its influence on the ring TIF is analyzed too. The relationship between the shape of the ring TIF and the lap-workpiece rotation speed ratio is discussed in this paper. The recipe for calculating dwell time for axisymmetric fabrication is discussed. The grinding process of a 1.8 m primary mirror is improved based on these results. The grinding process is accomplished after 30 circles of grinding, and the surface shape error is from PV 82 μm RMS 16.4 μm reduced to PV 13.5 μm RMS 2.5 μm.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Srivastava, K.G.
1962-04-01
Defect structure in single crystals of rutile was studied by dielectric measurements at 2 cps and above, before and after irradiation with hard x rays. The results were analyzed by a Cole-Cole plot, which is a circle with its cenier shifted away from the dielectric constant axis. X irradiation shifts the center of the Cole-Cole plot toward the dielectric constant axis, indicating a decrease in distribution of relaxation times by evacuation of electrons from their shallow traps, which after release produce interfacial polarization. An attempt was also made to calculate the a-c behavior from d-c data, but the errors atmore » frequencies of measurement were toe high, thus defying comparison with experimental data. (auth)« less
Design of free-space optical transmission system in computer tomography equipment
NASA Astrophysics Data System (ADS)
Liu, Min; Fu, Weiwei; Zhang, Tao
2018-04-01
Traditional computer tomography (CT) based on capacitive coupling cannot satisfy the high data rate transmission requirement. We design and experimentally demonstrate a free-space optical transmission system for CT equipment at a data rate of 10 Gb / s. Two interchangeable sections of 12 pieces of fiber with equal length is fabricated and tested by our designed laser phase distance measurement system. By locating the 12 collimators in the edge of the circle wheel evenly, the optical propagation characteristics for the 12 wired and wireless paths are similar, which can satisfy the requirement of high-speed CT transmission system. After bit error rate (BER) measurement in several conditions, the BER performances are below the value of 10 - 11, which has the potential in the future application scenario of CT equipment.
Multimodal determination of Rayleigh dispersion and attenuation curves using the circle fit method
NASA Astrophysics Data System (ADS)
Verachtert, R.; Lombaert, G.; Degrande, G.
2018-03-01
This paper introduces the circle fit method for the determination of multi-modal Rayleigh dispersion and attenuation curves as part of a Multichannel Analysis of Surface Waves (MASW) experiment. The wave field is transformed to the frequency-wavenumber (fk) domain using a discretized Hankel transform. In a Nyquist plot of the fk-spectrum, displaying the imaginary part against the real part, the Rayleigh wave modes correspond to circles. The experimental Rayleigh dispersion and attenuation curves are derived from the angular sweep of the central angle of these circles. The method can also be applied to the analytical fk-spectrum of the Green's function of a layered half-space in order to compute dispersion and attenuation curves, as an alternative to solving an eigenvalue problem. A MASW experiment is subsequently simulated for a site with a regular velocity profile and a site with a soft layer trapped between two stiffer layers. The performance of the circle fit method to determine the dispersion and attenuation curves is compared with the peak picking method and the half-power bandwidth method. The circle fit method is found to be the most accurate and robust method for the determination of the dispersion curves. When determining attenuation curves, the circle fit method and half-power bandwidth method are accurate if the mode exhibits a sharp peak in the fk-spectrum. Furthermore, simulated and theoretical attenuation curves determined with the circle fit method agree very well. A similar correspondence is not obtained when using the half-power bandwidth method. Finally, the circle fit method is applied to measurement data obtained for a MASW experiment at a site in Heverlee, Belgium. In order to validate the soil profile obtained from the inversion procedure, force-velocity transfer functions were computed and found in good correspondence with the experimental transfer functions, especially in the frequency range between 5 and 80 Hz.
2017-03-01
proposed. Expected profiles can incorporate a level of overdesign. Finally, the Design Integrity measuring techniques are applied to five Test Article ...Inserted into Test System Table 2 presents the results of the analysis applied to each of the test article designs. Each of the domains are...the lowest integrities. Based on the analysis, the DI metric shows measurable differentiation between all five Test Article Error Location Error
Guided discovery of the nine-point circle theorem and its proof
NASA Astrophysics Data System (ADS)
Buchbinder, Orly
2018-01-01
The nine-point circle theorem is one of the most beautiful and surprising theorems in Euclidean geometry. It establishes an existence of a circle passing through nine points, all of which are related to a single triangle. This paper describes a set of instructional activities that can help students discover the nine-point circle theorem through investigation in a dynamic geometry environment, and consequently prove it using a method of guided discovery. The paper concludes with a variety of suggestions for the ways in which the whole set of activities can be implemented in geometry classrooms.
Quality circles and their potential application to rural health care in Papua New Guinea.
Cibulskis, R E; Edwards, K N
1993-06-01
A quality circle is a group of service providers who meet regularly to solve problems relating to the quality of their work. This is an example of bottom-up rather than top-down management which has found considerable success in the industries of the developed world. This article describes the principles which govern the operation of quality circles, the expected benefits and how best to introduce them. The problems relating to the provision of quality health care in rural areas and the potential application of the quality circle methodology are discussed.
Homing by path integration when a locomotion trajectory crosses itself.
Yamamoto, Naohide; Meléndez, Jayleen A; Menzies, Derek T
2014-01-01
Path integration is a process with which navigators derive their current position and orientation by integrating self-motion signals along a locomotion trajectory. It has been suggested that path integration becomes disproportionately erroneous when the trajectory crosses itself. However, there is a possibility that this previous finding was confounded by effects of the length of a traveled path and the amount of turns experienced along the path, two factors that are known to affect path integration performance. The present study was designed to investigate whether the crossover of a locomotion trajectory truly increases errors of path integration. In an experiment, blindfolded human navigators were guided along four paths that varied in their lengths and turns, and attempted to walk directly back to the beginning of the paths. Only one of the four paths contained a crossover. Results showed that errors yielded from the path containing the crossover were not always larger than those observed in other paths, and the errors were attributed solely to the effects of longer path lengths or greater degrees of turns. These results demonstrated that path crossover does not always cause significant disruption in path integration processes. Implications of the present findings for models of path integration are discussed.
Ensemble Data Assimilation Without Ensembles: Methodology and Application to Ocean Data Assimilation
NASA Technical Reports Server (NTRS)
Keppenne, Christian L.; Rienecker, Michele M.; Kovach, Robin M.; Vernieres, Guillaume
2013-01-01
Two methods to estimate background error covariances for data assimilation are introduced. While both share properties with the ensemble Kalman filter (EnKF), they differ from it in that they do not require the integration of multiple model trajectories. Instead, all the necessary covariance information is obtained from a single model integration. The first method is referred-to as SAFE (Space Adaptive Forecast error Estimation) because it estimates error covariances from the spatial distribution of model variables within a single state vector. It can thus be thought of as sampling an ensemble in space. The second method, named FAST (Flow Adaptive error Statistics from a Time series), constructs an ensemble sampled from a moving window along a model trajectory. The underlying assumption in these methods is that forecast errors in data assimilation are primarily phase errors in space and/or time.
The Gasket of Circles: A Fractal of Circular Nature
ERIC Educational Resources Information Center
Haggar, Fred; Kricic, Senida
2017-01-01
Subdividing an equilateral triangle into four congruent triangles, then doing likewise to each of the three non-central triangles, and then again and again, leads to the Sierpinski gasket, from which the chaos game originated. An analogous procedure is hereforth applied to a circle, where a subdivision consists of two pairs of inscribed circles,…
Influence of a Mathematics Teachers' Circle on Elementary Teachers' Use of Problem Solving
ERIC Educational Resources Information Center
Garner, Mary L.; Watson, Virginia; Rogers, Beth; Head, Catherine
2017-01-01
Math teachers' circles are a form of professional development that is recommended by the Conference Board of the Mathematical Sciences in their publication Mathematical Education of Teachers II (2012). However, little research has been published on how effective math teachers' circles are in advancing the mathematical knowledge of teachers and…
Author Correction: Quantum Landauer erasure with a molecular nanomagnet
NASA Astrophysics Data System (ADS)
Gaudenzi, R.; Burzurí, E.; Maegawa, S.; van der Zant, H. S. J.; Luis, F.
2018-06-01
In the version of this Letter originally published, the key to the green and open circles in Fig. 4 was reversed; it should have shown that the green circles correspond to `From χ versus T' and the open circles correspond to `From χ versus Hy'. This has now been corrected in all versions of the Letter.
Growing a Circle of Courage Culture: One School's Journey
ERIC Educational Resources Information Center
Espiner, Deborah; Guild, Diane
2010-01-01
Mt. Richmond Special School is the first Circle of Courage school in New Zealand. The school reflects the richness of the cultural and learning diversity found in many New Zealand schools. Located in the heart of South Auckland, the school's 130 students represent a wide range of ethnic backgrounds. The universal values in the Circle of Courage…
Quality Circles: How Effective Are They in Improving Employee Performance and Attitudes?
ERIC Educational Resources Information Center
Buch, Kimberly; Raban, Amiram
1990-01-01
Used a quasi-experimental design to assess the effect of a quality circle intervention on behavior and attitudes of 88 employees at a large Midwestern organization. Results provide mixed support for the purported ability of circles to improve work behavior with no change for absenteeism and productivity but positive change for quality of work.…
Dynamic Investigation of Triangles Inscribed in a Circle, Which Tend to an Equilateral Triangle
ERIC Educational Resources Information Center
Stupel, Moshe; Oxman, Victor; Sigler, Avi
2017-01-01
We present a geometrical investigation of the process of creating an infinite sequence of triangles inscribed in a circle, whose areas, perimeters and lengths of radii of the inscribed circles tend to a limit in a monotonous manner. First, using geometrical software, we investigate four theorems that represent interesting geometrical properties,…
D'Nealian Handwriting versus Circle-Stick Print.
ERIC Educational Resources Information Center
Thurber, Donald N.
This paper argues against teaching children to make letters using circle-stick writing. It contends that the circle-stick method requires continued pen/pencil lifts hindering rhythm or flow in the writing process and that there is little carry-over value into cursive writing as the two scripts are totally different. D'Nealian print, one type of…
Unit Circles and Inverse Trigonometric Functions
ERIC Educational Resources Information Center
Barrera, Azael
2014-01-01
Historical accounts of trigonometry refer to the works of many Indian and Arab astronomers on the origin of the trigonometric functions as we know them now, in particular Abu al-Wafa (ca. 980 CE), who determined and named all known trigonometric functions from segments constructed on a regular circle and later on a unit circle (Moussa 2011;…
Virtual directions in paleomagnetism: A global and rapid approach to evaluate the NRM components.
NASA Astrophysics Data System (ADS)
Ramón, Maria J.; Pueyo, Emilio L.; Oliva-Urcia, Belén; Larrasoaña, Juan C.
2017-02-01
We introduce a method and software to process demagnetization data for a rapid and integrative estimation of characteristic remanent magnetization (ChRM) components. The virtual directions (VIDI) of a paleomagnetic site are “all” possible directions that can be calculated from a given demagnetization routine of “n” steps (being m the number of specimens in the site). If the ChRM can be defined for a site, it will be represented in the VIDI set. Directions can be calculated for successive steps using principal component analysis, both anchored to the origin (resultant virtual directions RVD; m * (n2+n)/2) and not anchored (difference virtual directions DVD; m * (n2-n)/2). The number of directions per specimen (n2) is very large and will enhance all ChRM components with noisy regions where two components were fitted together (mixing their unblocking intervals). In the same way, resultant and difference virtual circles (RVC, DVC) are calculated. Virtual directions and circles are a global and objective approach to unravel different natural remanent magnetization (NRM) components for a paleomagnetic site without any assumption. To better constrain the stable components, some filters can be applied, such as establishing an upper boundary to the MAD, removing samples with anomalous intensities, or stating a minimum number of demagnetization steps (objective filters) or selecting a given unblocking interval (subjective but based on the expertise). On the other hand, the VPD program also allows the application of standard approaches (classic PCA fitting of directions a circles) and other ancillary methods (stacking routine, linearity spectrum analysis) giving an objective, global and robust idea of the demagnetization structure with minimal assumptions. Application of the VIDI method to natural cases (outcrops in the Pyrenees and u-channel data from a Roman dam infill in northern Spain) and their comparison to other approaches (classic end-point, demagnetization circle analysis, stacking routine and linearity spectrum analysis) allows validation of this technique. The VIDI is a global approach and it is especially useful for large data sets and rapid estimation of the NRM components.
Gabriele, Michelle L.; Ishikawa, Hiroshi; Wollstein, Gadi; Bilonick, Richard A.; Townsend, Kelly A.; Kagemann, Larry; Wojtkowski, Maciej; Srinivasan, Vivek J.; Fujimoto, James G.; Duker, Jay S.; Schuman, Joel S.
2009-01-01
PURPOSE To investigate the effect on optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness measurements of varying the standard 3.4-mm-diameter circle location. METHODS The optic nerve head (ONH) region of 17 eyes of 17 healthy subjects was imaged with high-speed, ultrahigh-resolution OCT (hsUHR-OCT; 501 × 180 axial scans covering a 6 × 6-mm area; scan time, 3.84 seconds) for a comprehensive sampling. This method allows for systematic simulation of the variable circle placement effect. RNFL thickness was measured on this three-dimensional dataset by using a custom-designed software program. RNFL thickness was resampled along a 3.4-mm-diameter circle centered on the ONH, then along 3.4-mm circles shifted horizontally (x-shift), vertically (y-shift) and diagonally up to ±500 µm (at 100-µm intervals). Linear mixed-effects models were used to determine RNFL thickness as a function of the scan circle shift. A model for the distance between the two thickest measurements along the RNFL thickness circular profile (peak distance) was also calculated. RESULTS RNFL thickness tended to decrease with both positive and negative x- and y-shifts. The range of shifts that caused a decrease greater than the variability inherent to the commercial device was greater in both nasal and temporal quadrants than in the superior and inferior ones. The model for peak distance demonstrated that as the scan moves nasally, the RNFL peak distance increases, and as the circle moves temporally, the distance decreases. Vertical shifts had a minimal effect on peak distance. CONCLUSIONS The location of the OCT scan circle affects RNFL thickness measurements. Accurate registration of OCT scans is essential for measurement reproducibility and longitudinal examination (ClinicalTrials.gov number, NCT00286637). PMID:18515577
Observability Analysis of a MEMS INS/GPS Integration System with Gyroscope G-Sensitivity Errors
Fan, Chen; Hu, Xiaoping; He, Xiaofeng; Tang, Kanghua; Luo, Bing
2014-01-01
Gyroscopes based on micro-electromechanical system (MEMS) technology suffer in high-dynamic applications due to obvious g-sensitivity errors. These errors can induce large biases in the gyroscope, which can directly affect the accuracy of attitude estimation in the integration of the inertial navigation system (INS) and the Global Positioning System (GPS). The observability determines the existence of solutions for compensating them. In this paper, we investigate the observability of the INS/GPS system with consideration of the g-sensitivity errors. In terms of two types of g-sensitivity coefficients matrix, we add them as estimated states to the Kalman filter and analyze the observability of three or nine elements of the coefficient matrix respectively. A global observable condition of the system is presented and validated. Experimental results indicate that all the estimated states, which include position, velocity, attitude, gyro and accelerometer bias, and g-sensitivity coefficients, could be made observable by maneuvering based on the conditions. Compared with the integration system without compensation for the g-sensitivity errors, the attitude accuracy is raised obviously. PMID:25171122
Observability analysis of a MEMS INS/GPS integration system with gyroscope G-sensitivity errors.
Fan, Chen; Hu, Xiaoping; He, Xiaofeng; Tang, Kanghua; Luo, Bing
2014-08-28
Gyroscopes based on micro-electromechanical system (MEMS) technology suffer in high-dynamic applications due to obvious g-sensitivity errors. These errors can induce large biases in the gyroscope, which can directly affect the accuracy of attitude estimation in the integration of the inertial navigation system (INS) and the Global Positioning System (GPS). The observability determines the existence of solutions for compensating them. In this paper, we investigate the observability of the INS/GPS system with consideration of the g-sensitivity errors. In terms of two types of g-sensitivity coefficients matrix, we add them as estimated states to the Kalman filter and analyze the observability of three or nine elements of the coefficient matrix respectively. A global observable condition of the system is presented and validated. Experimental results indicate that all the estimated states, which include position, velocity, attitude, gyro and accelerometer bias, and g-sensitivity coefficients, could be made observable by maneuvering based on the conditions. Compared with the integration system without compensation for the g-sensitivity errors, the attitude accuracy is raised obviously.
Study on UKF based federal integrated navigation for high dynamic aviation
NASA Astrophysics Data System (ADS)
Zhao, Gang; Shao, Wei; Chen, Kai; Yan, Jie
2011-08-01
High dynamic aircraft is a very attractive new generation vehicles, in which provides near space aviation with large flight envelope both speed and altitude, for example the hypersonic vehicles. The complex flight environments for high dynamic vehicles require high accuracy and stability navigation scheme. Since the conventional Strapdown Inertial Navigation System (SINS) and Global Position System (GPS) federal integrated scheme based on EKF (Extended Kalman Filter) is invalidation in GPS single blackout situation because of high speed flight, a new high precision and stability integrated navigation approach is presented in this paper, in which the SINS, GPS and Celestial Navigation System (CNS) is combined as a federal information fusion configuration based on nonlinear Unscented Kalman Filter (UKF) algorithm. Firstly, the new integrated system state error is modeled. According to this error model, the SINS system is used as the navigation solution mathematic platform. The SINS combine with GPS constitute one error estimation filter subsystem based on UKF to obtain local optimal estimation, and the SINS combine with CNS constitute another error estimation subsystem. A non-reset federated configuration filter based on partial information is proposed to fuse two local optimal estimations to get global optimal error estimation, and the global optimal estimation is used to correct the SINS navigation solution. The χ 2 fault detection method is used to detect the subsystem fault, and the fault subsystem is isolation through fault interval to protect system away from the divergence. The integrated system takes advantages of SINS, GPS and CNS to an immense improvement for high accuracy and reliably high dynamic navigation application. Simulation result shows that federated fusion of using GPS and CNS to revise SINS solution is reasonable and availably with good estimation performance, which are satisfied with the demands of high dynamic flight navigation. The UKF is superior than EKF based integrated scheme, in which has smaller estimation error and quickly convergence rate.
Real-time monitoring of rolling-circle amplification using a modified molecular beacon design
Nilsson, Mats; Gullberg, Mats; Dahl, Fredrik; Szuhai, Karoly; Raap, Anton K.
2002-01-01
We describe a method to monitor rolling-circle replication of circular oligonucleotides in dual-color and in real-time using molecular beacons. The method can be used to study the kinetics of the polymerization reaction and to amplify and quantify circularized oligonucleotide probes in a rolling-circle amplification (RCA) reaction. Modified molecular beacons were made of 2′-O-Me-RNA to prevent 3′ exonucleolytic degradation by the polymerase used. Moreover, the complement of one of the stem sequences of the molecular beacon was included in the RCA products to avoid fluorescence quenching due to inter-molecular hybridization of neighboring molecular beacons hybridizing to the concatemeric polymerization product. The method allows highly accurate quantification of circularized DNA over a broad concentration range by relating the signal from the test DNA circle to an internal reference DNA circle reporting in a distinct fluorescence color. PMID:12136114
Synthesis of boron nitride coatings on quartz fibers: Thickness control and mechanism research
NASA Astrophysics Data System (ADS)
Zheng, Yu; Wang, Shubin
2011-10-01
Boron nitride (BN) coatings were successfully synthesized on quartz fibers by dip-coating in boric acid and urea solutions at 700 °C. The SEM micrographs indicated that the quartz fibers were fully covered by coatings with smooth surface. The XRD, FT-IR, XPS spectra and HR-TEM results showed that the composition of the coatings which combined closely with the quartz fibers was polycrystalline h-BN. By changing the dip circles, the coating thickness was well controlled. The thicknesses of samples dipped less than six circles increased linearly with dipping-circles; and the increment of coating thickness would slow down when the fibers were dipped 10 circles. After being dipped for 10 circles, the thickness was about 300 nm. The coating thickness was also established by calculation and the calculated results were consistent with the results measured by micrograph.
NASA Astrophysics Data System (ADS)
Archimedes; Heath, Thomas L.
2009-09-01
Part I. Introduction: 1. Archimedes; 2. Manuscripts and principle editions; 3. Relation of Archimedes to his predecessors; 4. Arithmetic in Archimedes; 5. On the problem known as neuseis; 6. Cubic equations; 7. Anticipations by Archimedes of the integral calculus; 8. The terminology of Archimedes; Part II. The Works of Archimedes: 1. On the sphere and cylinder; 2. Measurement of a circle; 3. On conoids and spheroids; 4. On spirals; 5. On the equilibrium of planes; 6. The sand-reckoner; 7. Quadrature of the parabola; 8. On floating bodies; 9. Book of lemmas; 10. The cattle-problem.
Hohimer, John P.; Craft, David C.
1994-01-01
Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction.
Sensory feedback in a bump attractor model of path integration.
Poll, Daniel B; Nguyen, Khanh; Kilpatrick, Zachary P
2016-04-01
Mammalian spatial navigation systems utilize several different sensory information channels. This information is converted into a neural code that represents the animal's current position in space by engaging place cell, grid cell, and head direction cell networks. In particular, sensory landmark (allothetic) cues can be utilized in concert with an animal's knowledge of its own velocity (idiothetic) cues to generate a more accurate representation of position than path integration provides on its own (Battaglia et al. The Journal of Neuroscience 24(19):4541-4550 (2004)). We develop a computational model that merges path integration with feedback from external sensory cues that provide a reliable representation of spatial position along an annular track. Starting with a continuous bump attractor model, we explore the impact of synaptic spatial asymmetry and heterogeneity, which disrupt the position code of the path integration process. We use asymptotic analysis to reduce the bump attractor model to a single scalar equation whose potential represents the impact of asymmetry and heterogeneity. Such imperfections cause errors to build up when the network performs path integration, but these errors can be corrected by an external control signal representing the effects of sensory cues. We demonstrate that there is an optimal strength and decay rate of the control signal when cues appear either periodically or randomly. A similar analysis is performed when errors in path integration arise from dynamic noise fluctuations. Again, there is an optimal strength and decay of discrete control that minimizes the path integration error.
A semiempirical error estimation technique for PWV derived from atmospheric radiosonde data
NASA Astrophysics Data System (ADS)
Castro-Almazán, Julio A.; Pérez-Jordán, Gabriel; Muñoz-Tuñón, Casiana
2016-09-01
A semiempirical method for estimating the error and optimum number of sampled levels in precipitable water vapour (PWV) determinations from atmospheric radiosoundings is proposed. Two terms have been considered: the uncertainties in the measurements and the sampling error. Also, the uncertainty has been separated in the variance and covariance components. The sampling and covariance components have been modelled from an empirical dataset of 205 high-vertical-resolution radiosounding profiles, equipped with Vaisala RS80 and RS92 sondes at four different locations: Güímar (GUI) in Tenerife, at sea level, and the astronomical observatory at Roque de los Muchachos (ORM, 2300 m a.s.l.) on La Palma (both on the Canary Islands, Spain), Lindenberg (LIN) in continental Germany, and Ny-Ålesund (NYA) in the Svalbard Islands, within the Arctic Circle. The balloons at the ORM were launched during intensive and unique site-testing runs carried out in 1990 and 1995, while the data for the other sites were obtained from radiosounding stations operating for a period of 1 year (2013-2014). The PWV values ranged between ˜ 0.9 and ˜ 41 mm. The method sub-samples the profile for error minimization. The result is the minimum error and the optimum number of levels. The results obtained in the four sites studied showed that the ORM is the driest of the four locations and the one with the fastest vertical decay of PWV. The exponential autocorrelation pressure lags ranged from 175 hPa (ORM) to 500 hPa (LIN). The results show a coherent behaviour with no biases as a function of the profile. The final error is roughly proportional to PWV whereas the optimum number of levels (N0) is the reverse. The value of N0 is less than 400 for 77 % of the profiles and the absolute errors are always < 0.6 mm. The median relative error is 2.0 ± 0.7 % and the 90th percentile P90 = 4.6 %. Therefore, whereas a radiosounding samples at least N0 uniform vertical levels, depending on the water vapour content and distribution of the atmosphere, the error in the PWV estimate is likely to stay below ≈ 3 %, even for dry conditions.
Roentgen stereophotogrammetric analysis of metal-backed hemispherical cups without attached markers.
Valstar, E R; Spoor, C W; Nelissen, R G; Rozing, P M
1997-11-01
A method for the detection of micromotion of a metal-backed hemispherical acetabular cup is presented and tested. Unlike in conventional roentgen stereophotogrammetric analysis, the cup does not have to be marked with tantalum markers; the micromotion is calculated from the contours of the hemispherical part and the base circle of the cup. In this way, two rotations (tilt and anteversion) and the translations along the three cardinal axes are obtained. In a phantom study, the maximum error in the position of the cup's centre was 0.04 mm. The mean error in the orientation of the cup was 0.41 degree, with a 95% confidence interval of 0.28-0.54 degree. The in vivo accuracy was tested by repeated measurement of 21 radiographs from seven patients. The upper bound of the 95% tolerance interval for the translations along the transversal, longitudinal, and sagittal axes was 0.09, 0.07, and 0.34 mm, respectively: for the rotation, this upper bound was 0.39 degree. These results show that the new method, in which the position and orientation of metal-backed hemispherical cup is calculated from its projected contours, is a simple and accurate alternative to attaching markers to the cup.
Validity and test-retest reliability of the six-spot step test in persons after stroke.
Arvidsson Lindvall, Mialinn; Anderzén-Carlsson, Agneta; Appelros, Peter; Forsberg, Anette
2018-06-06
After stroke, asymmetric weight distribution is common with decreased balance control in standing and walking. The six-spot step test (SSST) includes a 5-m walk during which one leg shoves wooden blocks out of circles marked on the floor, thus assessing the ability to take load on each leg. The aim of the present study was to investigate the convergent and discriminant validity and test-retest reliability of the SSST in persons with stroke. Eighty-one participants were included. A cross-sectional study was performed, in which the SSST was conducted twice, 3-7 days apart. Validity was investigated using measures of dynamic balance and walking. Reliability was assessed using intraclass correlation coefficient, standard error of the measurement (SEM), and smallest real difference (SRD). The convergent validity was strong to moderate, and the test-retest reliability was good. The SEM% was 14.7%, and the SRD% was 40.8% based on the mean of four walks shoving twice with the paretic and twice with the non-paretic leg. Values on random measurement error were high affecting the use of the SSST for follow-up evaluations but the SSST can be a complementary measure of gait and balance.
Zhang, Fumin; Qu, Xinghua; Ouyang, Jianfei
2012-01-01
A novel measurement prototype based on a mobile vehicle that carries a laser scanning sensor is proposed. The prototype is intended for the automated measurement of the interior 3D geometry of large-diameter long-stepped pipes. The laser displacement sensor, which has a small measurement range, is mounted on an extended arm of known length. It is scanned to improve the measurement accuracy for large-sized pipes. A fixing mechanism based on two sections is designed to ensure that the stepped pipe is concentric with the axis of rotation of the system. Data are acquired in a cylindrical coordinate system and fitted in a circle to determine diameter. Systematic errors covering arm length, tilt, and offset errors are analyzed and calibrated. The proposed system is applied to sample parts and the results are discussed to verify its effectiveness. This technique measures a diameter of 600 mm with an uncertainty of 0.02 mm at a 95% confidence probability. A repeatability test is performed to examine precision, which is 1.1 μm. A laser tracker is used to verify the measurement accuracy of the system, which is evaluated as 9 μm within a diameter of 600 mm.
Acetabular rim and surface segmentation for hip surgery planning and dysplasia evaluation
NASA Astrophysics Data System (ADS)
Tan, Sovira; Yao, Jianhua; Yao, Lawrence; Summers, Ronald M.; Ward, Michael M.
2008-03-01
Knowledge of the acetabular rim and surface can be invaluable for hip surgery planning and dysplasia evaluation. The acetabular rim can also be used as a landmark for registration purposes. At the present time acetabular features are mostly extracted manually at great cost of time and human labor. Using a recent level set algorithm that can evolve on the surface of a 3D object represented by a triangular mesh we automatically extracted rims and surfaces of acetabulae. The level set is guided by curvature features on the mesh. It can segment portions of a surface that are bounded by a line of extremal curvature (ridgeline or crestline). The rim of the acetabulum is such an extremal curvature line. Our material consists of eight hemi-pelvis surfaces. The algorithm is initiated by putting a small circle (level set seed) at the center of the acetabular surface. Because this surface distinctively has the form of a cup we were able to use the Shape Index feature to automatically extract an approximate center. The circle then expands and deforms so as to take the shape of the acetabular rim. The results were visually inspected. Only minor errors were detected. The algorithm also proved to be robust. Seed placement was satisfactory for the eight hemi-pelvis surfaces without changing any parameters. For the level set evolution we were able to use a single set of parameters for seven out of eight surfaces.
Research on fast algorithm of small UAV navigation in non-linear matrix reductionism method
NASA Astrophysics Data System (ADS)
Zhang, Xiao; Fang, Jiancheng; Sheng, Wei; Cao, Juanjuan
2008-10-01
The low Reynolds numbers of small UAV will result in unfavorable aerodynamic conditions to support controlled flight. And as operated near ground, the small UAV will be affected seriously by low-frequency interference caused by atmospheric disturbance. Therefore, the GNC system needs high frequency of attitude estimation and control to realize the steady of the UAV. In company with the dimensional of small UAV dwindling away, its GNC system is more and more taken embedded designing technology to reach the purpose of compactness, light weight and low power consumption. At the same time, the operational capability of GNC system also gets limit in a certain extent. Therefore, a kind of high speed navigation algorithm design becomes the imminence demand of GNC system. Aiming at such requirement, a kind of non-linearity matrix reduction approach is adopted in this paper to create a new high speed navigation algorithm which holds the radius of meridian circle and prime vertical circle as constant and linearizes the position matrix calculation formulae of navigation equation. Compared with normal navigation algorithm, this high speed navigation algorithm decreases 17.3% operand. Within small UAV"s mission radius (20km), the accuracy of position error is less than 0.13m. The results of semi-physical experiments and small UAV's auto pilot testing proved that this algorithm can realize high frequency attitude estimation and control. It will avoid low-frequency interference caused by atmospheric disturbance properly.
NASA Astrophysics Data System (ADS)
Genberg, Victor L.; Michels, Gregory J.
2017-08-01
The ultimate design goal of an optical system subjected to dynamic loads is to minimize system level wavefront error (WFE). In random response analysis, system WFE is difficult to predict from finite element results due to the loss of phase information. In the past, the use of ystem WFE was limited by the difficulty of obtaining a linear optics model. In this paper, an automated method for determining system level WFE using a linear optics model is presented. An error estimate is included in the analysis output based on fitting errors of mode shapes. The technique is demonstrated by example with SigFit, a commercially available tool integrating mechanical analysis with optical analysis.
A Historical Note on the Proof of the Area of a Circle
ERIC Educational Resources Information Center
Wilamowsky, Yonah; Epstein, Sheldon; Dickman, Bernard
2011-01-01
Proofs that the area of a circle is nr[superscript 2] can be found in mathematical literature dating as far back as the time of the Greeks. The early proofs, e.g. Archimedes, involved dividing the circle into wedges and then fitting the wedges together in a way to approximate a rectangle. Later more sophisticated proofs relied on arguments…
The Revival of Research Circles: Meeting the Needs of Modern Aging and the Third Age
ERIC Educational Resources Information Center
Ostlund, Britt
2008-01-01
This article provides evidence that it is worthwhile to reconsider the traditional research circle method as a means of involving people in the third age in fulfilling their needs to participate in learning activities and make their voices heard. The findings are based on three cases of research circles consistently driven by the interests of the…
Providing a Full Circle of Support to Teachers in an Inclusive Elementary School
ERIC Educational Resources Information Center
Waldron, Nancy L.; Redd, Lacy
2011-01-01
Providing a full circle of support to teachers in an inclusive elementary school, the Newberry Elementary School (NES) principal and staff have worked for 5 years to ensure the inclusion of students with disabilities in general education classrooms. The authors would like to share their perceptions of how this full circle (the multiple systems) of…
Finding the Maximal Area of Bounded Polygons in a Circle
ERIC Educational Resources Information Center
Rokach, Arie
2005-01-01
The article deals with the area of polygons that are inscribed in a given circle. Naturally, the following question arises: Among all n-polygons that are inscribed in a given circle, which one has the biggest area? Intuitively, it may be guessed that is suitable for secondary students, and without any use id calculus, but only using very…
The Box and the Circle--Two Systems of Life: A Model for Understanding Native-Non-Native Issues.
ERIC Educational Resources Information Center
Derrick, Jann
Working as a family systems therapist with Native and non-Native families, the author observed two opposing social systems. Non-native families systems typify "The Box System," whereas native family systems portray "The Circle System." A few characteristics of the Circle System are: (1) a focus on life and peacefulness; (2) females and children…
ERIC Educational Resources Information Center
Steese, Stephanie; Dollette, Maya; Phillips, William; Hossfeld, Elizabeth; Matthews, Gail; Taormina, Giovanna
2006-01-01
The Girls' Circle is a support group for adolescent girls developed by Beth Hossfeld and Giovanna Taormina as a unique program that addresses the needs of girls by focusing on increasing connections, building empathic skills, and developing resiliency. The present study evaluates the effectiveness of the Girls' Circle intervention on improving…
Ostasiewski, P; Fugate, D L
1994-01-01
Adapting the quality-circle concept to a health care setting helped one hospital solve a problem and boosted its image among patients. The "patient circle" technique is one step health care providers can take toward delivering "total customer value," a quality perception that can mean the difference between surviving and thriving in the future.
DETAIL VIEW OF PIEDMONT AVENUE TRAFFIC CIRCLE AT INTERSECTION OF ...
DETAIL VIEW OF PIEDMONT AVENUE TRAFFIC CIRCLE AT INTERSECTION OF CHANNING WAY. SEEN FROM EAST SIDE OF CIRCLE LOOKING NORTH AT 2395 PIEDMONT, SIGMA PI HOUSE BY FREDERICK H. REIMERS, 1928. Photograph by Brian Grogan, July 8, 2007 - Piedmont Way & the Berkeley Property Tract, East of College Avenue between Dwight Way & U.C. Memorial Stadium, Berkeley, Alameda County, CA
Evolved Expendable Launch Vehicle (EELV)
2015-12-15
FY13+ Phase I Buy Contractor: United Launch Services, LLC Contractor Location: 9501 East Panorama Circle Centennial , CO 80112 Contract Number...Contract Name: FY13+ Phase I Buy Contractor: United Launch Services, LLC Contractor Location: 9501 East Panorama Circle Centennial , CO 80112 Contract...FY12 EELV Launch Services (ELS5) Contractor: United Launch Services, LLC. Contractor Location: 9501 East Panorama Circle Centennial , CO 80112
Geometrical Solutions of Quadratic Equations.
ERIC Educational Resources Information Center
Grewal, A. S.; Godloza, L.
1999-01-01
Demonstrates that the equation of a circle (x-h)2 + (y-k)2 = r2 with center (h; k) and radius r reduces to a quadratic equation x2-2xh + (h2 + k2 -r2) = O at the intersection with the x-axis. Illustrates how to determine the center of a circle as well as a point on a circle. (Author/ASK)
Method for construction of normalized cDNA libraries
Soares, Marcelo B.; Efstratiadis, Argiris
1998-01-01
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries.
Method for construction of normalized cDNA libraries
Soares, M.B.; Efstratiadis, A.
1998-11-03
This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3` noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to appropriate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. This invention also provides normalized cDNA libraries generated by the above-described method and uses of the generated libraries. 19 figs.
Sometimes area counts more than number.
Hurewitz, Felicia; Gelman, Rochel; Schnitzer, Brian
2006-12-19
Using an interference paradigm, we show across three experiments that adults' order judgments of numbers, sizes, or combined area of dots in pairs of arrays occur spontaneously and automatically, but at different speeds and levels of accuracy. Experiment 1 used circles whose sizes varied between but not within arrays. Variation in circle size interfered with judgments of which array had more circles. Experiment 2 used displays in which circle size varied within and between arrays. Between-array differences in the amount of "circle stuff" (area occupied by circles) interfered with judgments of number. Experiment 3 examined whether variation in number also interferes with judgments of area. Interference between discrete and continuous stimulus dimensions occurred in both directions, although it was stronger from the continuous to the discrete than vice versa. These results bear on interpretations of studies with infants and preschoolers wherein subjects respond on the basis of continuous quantity rather than discrete quantity. In light of our results with adults, these findings do not license the conclusion that young children cannot represent discrete quantity. Absent data on attentional hierarchies and speed of processing, it is premature to conclude that infant and child quantity processes are fundamentally different from that of adults.
Walking straight into circles.
Souman, Jan L; Frissen, Ilja; Sreenivasa, Manish N; Ernst, Marc O
2009-09-29
Common belief has it that people who get lost in unfamiliar terrain often end up walking in circles. Although uncorroborated by empirical data, this belief has widely permeated popular culture. Here, we tested the ability of humans to walk on a straight course through unfamiliar terrain in two different environments: a large forest area and the Sahara desert. Walking trajectories of several hours were captured via global positioning system, showing that participants repeatedly walked in circles when they could not see the sun. Conversely, when the sun was visible, participants sometimes veered from a straight course but did not walk in circles. We tested various explanations for this walking behavior by assessing the ability of people to maintain a fixed course while blindfolded. Under these conditions, participants walked in often surprisingly small circles (diameter < 20 m), though rarely in a systematic direction. These results rule out a general explanation in terms of biomechanical asymmetries or other general biases [1-6]. Instead, they suggest that veering from a straight course is the result of accumulating noise in the sensorimotor system, which, without an external directional reference to recalibrate the subjective straight ahead, may cause people to walk in circles.
An unusual case of olecranon tuberculosis.
Megas, Panagiotis; Karageorgos, Athanasios; Gliatis, Ioannis; Marangos, Markos
2008-08-01
A 67-year-old woman presented with erythema and swelling over her left elbow. She felt pain during palpation of the olecranon, while the range of elbow motion was slightly reduced (02 in circle-302 in circle-1302 in circle). She had been treated conservatively elsewhere for 3 months with nonsteroidal anti-inflammatory drugs and splint immobilization. Radiographs and computed tomography showed an osteolytic area over the olecranon with cortex disruption. She underwent open biopsy of the olecranon, and the histologic features were compatible with tuberculosis. Erythrocyte sedimentation rate was elevated and she had a positive Mantoux test (14 mm). She mentioned no history of pulmonary disease and had a normal chest radiograph. She received antituberculous treatment (isoniazid, rifambin, and pyrazinamide) for 2 months without obvious improvement. She underwent surgical debridement of the olecranon while she continued antituberculous treatment for 12 months, discontinuing pyrazinamide after the third month. After the completion of antituberculous treatment, the patient was pain-free, without local signs of infection and with improved range of motion (02 in circle-202 in circle-1452 in circle). Early diagnosis and treatment of olecranon tuberculosis is of great value, and the prognosis is good when there is no spread in the elbow joint.
Drones at the Beach - Surf Zone Monitoring Using Rotary Wing Unmanned Aerial Vehicles
NASA Astrophysics Data System (ADS)
Rynne, P.; Brouwer, R.; de Schipper, M. A.; Graham, F.; Reniers, A.; MacMahan, J. H.
2014-12-01
We investigate the potential of rotary wing Unmanned Aerial Vehicles (UAVs) to monitor the surf zone. In recent years, the arrival of lightweight, high-capacity batteries, low-power electronics and compact high-definition cameras has driven the development of commercially available UAVs for hobbyists. Moreover, the low operation costs have increased their potential for scientific research as these UAVs are extremely flexible surveying platforms. The UAVs can fly for ~12 min with a mean loiter radius of 1 - 3.5 m and a mean loiter error of 0.75 - 4.5 m, depending on the environmental conditions, flying style, battery type and vehicle type. Our experiments using multiple, alternating UAVs show that it is possible to have near continuous imagery data with similar Fields Of View. The images obtained from the UAVs (Fig. 1a), and in combination with surveyed Ground Control Points (GCPs) (Fig. 1b, red squares and white circles), can be geo-rectified (Fig. 1c) to pixel resolution between 0.01 - 1 m and a reprojection error, i.e. the difference between the surveyed GPS location of a GCP and the location of the GCP obtained from the geo-rectified image, of O(1 m). These geo-rectified images provide data on a variety of coastal aspects, such as beach width (Wb(x,t)), surf zone width (Wsf(x,t)), wave breaking location (rectangle B), beach usage (circle C) and location of dune vegegation (rectangle D), amongst others. Additionally, the possibility to have consecutive, high frequency (up to 2 Hz) rectified images makes the UAVs a great data instrument for spatially and temporally variable systems, such as the surf zone. Our first observations with the UAVs reveal the potential to quickly obtain surf zone and beach characteristics in response to storms or for day to day beach information, as well as the scientific pursuits of surf zone kinematics on different spatial and temporal scales, and dispersion and advection estimates of pollutants/dye. A selection of findings from several field experiments and using multiple optical instruments will be showed at the meeting, discussing the new possibilities rotary wing UAVs can offer for surf zone research.
THERP and HEART integrated methodology for human error assessment
NASA Astrophysics Data System (ADS)
Castiglia, Francesco; Giardina, Mariarosa; Tomarchio, Elio
2015-11-01
THERP and HEART integrated methodology is proposed to investigate accident scenarios that involve operator errors during high-dose-rate (HDR) treatments. The new approach has been modified on the basis of fuzzy set concept with the aim of prioritizing an exhaustive list of erroneous tasks that can lead to patient radiological overexposures. The results allow for the identification of human errors that are necessary to achieve a better understanding of health hazards in the radiotherapy treatment process, so that it can be properly monitored and appropriately managed.
Mafusire, Cosmas; Krüger, Tjaart P J
2018-06-01
The concept of orthonormal vector circle polynomials is revisited by deriving a set from the Cartesian gradient of Zernike polynomials in a unit circle using a matrix-based approach. The heart of this model is a closed-form matrix equation of the gradient of Zernike circle polynomials expressed as a linear combination of lower-order Zernike circle polynomials related through a gradient matrix. This is a sparse matrix whose elements are two-dimensional standard basis transverse Euclidean vectors. Using the outer product form of the Cholesky decomposition, the gradient matrix is used to calculate a new matrix, which we used to express the Cartesian gradient of the Zernike circle polynomials as a linear combination of orthonormal vector circle polynomials. Since this new matrix is singular, the orthonormal vector polynomials are recovered by reducing the matrix to its row echelon form using the Gauss-Jordan elimination method. We extend the model to derive orthonormal vector general polynomials, which are orthonormal in a general pupil by performing a similarity transformation on the gradient matrix to give its equivalent in the general pupil. The outer form of the Gram-Schmidt procedure and the Gauss-Jordan elimination method are then applied to the general pupil to generate the orthonormal vector general polynomials from the gradient of the orthonormal Zernike-based polynomials. The performance of the model is demonstrated with a simulated wavefront in a square pupil inscribed in a unit circle.
Yang, Yanqiang; Zhang, Chunxi; Lu, Jiazhen
2017-01-01
Strapdown inertial navigation system/celestial navigation system (SINS/CNS) integrated navigation is a fully autonomous and high precision method, which has been widely used to improve the hitting accuracy and quick reaction capability of near-Earth flight vehicles. The installation errors between SINS and star sensors have been one of the main factors that restrict the actual accuracy of SINS/CNS. In this paper, an integration algorithm based on the star vector observations is derived considering the star sensor installation error. Then, the star sensor installation error is accurately estimated based on Kalman Filtering (KF). Meanwhile, a local observability analysis is performed on the rank of observability matrix obtained via linearization observation equation, and the observable conditions are presented and validated. The number of star vectors should be greater than or equal to 2, and the times of posture adjustment also should be greater than or equal to 2. Simulations indicate that the star sensor installation error could be readily observable based on the maneuvering condition; moreover, the attitude errors of SINS are less than 7 arc-seconds. This analysis method and conclusion are useful in the ballistic trajectory design of near-Earth flight vehicles. PMID:28275211
Topographic Map of Pathfinder Landing Site
NASA Technical Reports Server (NTRS)
1997-01-01
Topographic map of the landing site, to a distance of 60 meters from the lander in the LSC coordinate system. The lander is shown schematically in the center; 2.5 meter radius circle (black) centered on the camera was not mapped. Gentle relief [root mean square (rms) elevation variation 0.5 m; rms a directional slope 4O] and organization of topography into northwest and northeast-trending ridges about 20 meters apart are apparent. Roughly 30% of the illustrated area is hidden from the camera behind these ridges. Contours (0.2 m interval) and color coding of elevations were generated from a digital terrain model, which was interpolated by kriging from approximately 700 measured points. Angular and parallax point coordinates were measured manually on a large (5 m length) anaglyphic uncontrolled mosaic and used to calculate Cartesian (LSC) coordinates. Errors in azimuth on the order of 10 are therefore likely; elevation errors were minimized by referencing elevations to the local horizon. The uncertainty in range measurements increases quadratically with range. Given a measurement error of 1/2 pixel, the expected precision in range is 0.3 meter at 10 meter range, and 10 meters at 60 meter range. Repeated measurements were made, compared, and edited for consistency to improve the range precision. Systematic errors undoubtedly remain and will be corrected in future maps compiled digitally from geometrically controlled images. Cartographic processing by U.S. Geological Survey.
NOTE: original caption as published in Science MagazineMars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).ERIC Educational Resources Information Center
Rothlein, Liz; Einspruch, Eric
A total of 203 teachers of 5-year-olds in public school kindergartens representing 35 states responded to a questionnaire about traditional circle games. The teachers were asked to identify three of the favorite traditional circle games used in their classrooms and to indicate how often and how long the games were played. In addition, teachers…
Acquiring Combat Capability through Innovative Uses of Public-Private Partnerships
2006-06-01
needed for a vital fiber -optic link near the Arctic Circle. Then, we will explore the history of the Energy Saving Performance Contracts (ESPCs...research examines Hannon Armstrong’s “fee for service contract” solution to funding the vital fiber -optic link near the Arctic Circle. The second...5 A. INNOVATIVE USE OF FEE FOR SERVICE CONTRACT .....................5 1. Introduction to the Arctic Circle Fiber
1984-08-01
more times. Dr. Kaoru Ishikawa , a professor at the University of Tokyo and a board member of JUSE, used the efforts of Dr. Juran as the background for...his later work with quality circles. Dr. Ishikawa and the JUSE are generally credited with formalizing the modern Japanese quality circle technique in
ERIC Educational Resources Information Center
Mary, Latisha
2014-01-01
The aim of this study was to investigate the role of co-operative games and circle time activities in fostering positive peer relations in two French Primary classrooms (N = 40). It presents French teachers' and pupils' perceptions of a set of co-operative games and circle time activities implemented within a year long study on personal, social…
ERIC Educational Resources Information Center
Redmond, Theresa
2016-01-01
This essay is a response to Brown's (2015) article describing her strategy of transaction circles as a student-centered, culturally responsive, and democratic literacy practice. In my response, I provide further evidence from the field of media literacy education (MLE) that serves to enhance Brown's argument for using transaction circles in order…
2001-12-13
6-18 6.13. Apollonius Circle for the Case of Two Unequal Power Radars . . . 6-20 6.14. Solution Triangle...Voronoi edge is an Apollonius circle [32, 19]. In this section, we are concerned with the optimality of the Voronoi path for the two radar exposure...Comparison of Cost vs. Path Length for Constrained Trajectories Around and Between Two Radars 6-18 from the two radars is an Apollonius circle
ERIC Educational Resources Information Center
Hanson, Thomas; Polik, Jeff; Cerna, Rebeca
2017-01-01
An activity for eliciting student involvement in collaborative decision-making and problem-solving with adults--the student listening circle workshop--is examined for the first time through an experimental study of its effects on participating students. A student listening circle is a facilitated focus group in which students articulate to adults…
Study Circles at the Pharmacy--A New Model for Diabetes Education in Groups.
ERIC Educational Resources Information Center
Sarkadi, Anna; Rosenqvist, Urban
1999-01-01
Tests the feasibility of a one-year group education model for patients with type 2 diabetes in Sweden. Within study circles led by pharmacists, participants learned to self-monitor glucose, to interpret the results and to act upon them. Results show that study circles held at pharmacies are a feasible way of education persons with type 2 diabetes.…
To Believe the Past or to Trust the Future
ERIC Educational Resources Information Center
Jin, Fengtao; Zhou, Zhaoyan
2012-01-01
A small ball rolls down from a quarter-circle to a frictionless plane. What will be the magnitude of the normal force when the ball arrives at the tangent point of the circle and the plane? According to the centripetal force formula, the normal force will be 3 "mg" when the curvature radius of the circle is considered, but will be "mg" instead…
ERIC Educational Resources Information Center
Schumacher, Martha Ann
2012-01-01
Restorative Practices and Restorative Justice programs in schools are a new and emerging field. Meeting in Circles to build community, resolve conflict, and learn interactively are core components of these programs. This ethnographic study, which took place February 2010 to December 2011, evaluates 12 small, out-of-classroom Talking Circles for 60…
CIRCLE Enhancement After Myopic SMILE.
Siedlecki, Jakob; Luft, Nikolaus; Mayer, Wolfgang J; Siedlecki, Martin; Kook, Daniel; Meyer, Bertram; Bechmann, Martin; Wiltfang, Rainer; Priglinger, Siegfried G; Dirisamer, Martin
2018-05-01
To report the outcomes of enhancement after small incision lenticule extraction (SMILE) using the VisuMax CIRCLE option (Carl Zeiss Meditec AG, Jena, Germany), which converts the SMILE cap into a femtosecond LASIK flap for secondary excimer laser application. Of 2,065 SMILE procedures, 22 eyes (1.1%) re-treated with CIRCLE with a follow-up of 3 months were included in the analysis. SMILE was performed in the usual manner. For re-treatment, the CIRCLE procedure was performed with pattern D flap creation on the VisuMax system and subsequent excimer laser ablation with a Zeiss MEL 90 laser (Carl Zeiss Meditec) with plano target in all cases. Spherical equivalent was -5.56 ± 2.22 diopters (D) before SMILE and -0.51 ± 1.08 D before CIRCLE. CIRCLE enhancement was performed after a mean of 10.0 ± 7.9 months, allowed for safe flap lifting in all eyes, and resulted in a final manifest refraction spherical equivalent of 0.18 ± 0.31 D at 3 months (P < .008). The number of eyes within 0.50 and 1.00 D from target refraction increased from 31.8% to 90.9% and from 77.3% to 100%, respectively. Mean uncorrected distance visual acuity (UDVA) had already improved from 0.37 ± 0.16 to 0.08 ± 0.16 logMAR at 1 week (P < .0001), resulting in 0.03 ± 0.07 logMAR at 3 months (P < .0001). All eyes gained at least one line of UDVA. Corrected distance visual acuity (CDVA) remained unchanged at all time points (before vs after CIRCLE, P = .40). Two eyes (9.1 %) lost one line of CDVA; no eye lost two or more lines. The safety and efficacy indices were 1.03 and 0.97 at 3 months. The CIRCLE procedure represents an effective re-treatment option after SMILE. Compared to surface ablation re-treatment after SMILE, CIRCLE seems to offer advantages in respect to speed of visual recovery, safety, and predictability, but at the price of flap creation. [J Refract Surg. 2018;34(5):304-309.]. Copyright 2018, SLACK Incorporated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haghighipour, Nader; Scott, Edward R. D., E-mail: nader@ifa.hawaii.edu
2012-04-20
In their model for the origin of the parent bodies of iron meteorites, Bottke et al. proposed differentiated planetesimals, formed in 1-2 AU during the first 1.5 Myr, as the parent bodies, and suggested that these objects and their fragments were scattered into the asteroid belt as a result of interactions with planetary embryos. Although viable, this model does not include the effect of a giant planet that might have existed or been growing in the outer regions. We present the results of a concept study where we have examined the effect of a planetary body in the orbit ofmore » Jupiter on the early scattering of planetesimals from the terrestrial region into the asteroid belt. We integrated the orbits of a large battery of planetesimals in a disk of planetary embryos and studied their evolutions for different values of the mass of the planet. Results indicate that when the mass of the planet is smaller than 10 M{sub Circled-Plus }, its effects on the interactions among planetesimals and planetary embryos are negligible. However, when the planet mass is between 10 and 50 M{sub Circled-Plus }, simulations point to a transitional regime with {approx}50 M{sub Circled-Plus} being the value for which the perturbing effect of the planet can no longer be ignored. Simulations also show that further increase of the mass of the planet strongly reduces the efficiency of the scattering of planetesimals from the terrestrial planet region into the asteroid belt. We present the results of our simulations and discuss their possible implications for the time of giant planet formation.« less
NASA Astrophysics Data System (ADS)
Mihn, Byeong-Hee; Choi, Goeun; Lee, Yong Sam
2017-03-01
This study examines the scale unique instruments used for astronomical observation during the Joseon dynasty. The Small Simplified Armillary Sphere (小簡儀, So-ganui) and the Sun-and-Stars Time-Determining Instrument (日星定時儀, Ilseong-jeongsi-ui) are minimized astronomical instruments, which can be characterized, respectively, as an observational instrument and a clock, and were influenced by the Simplified Armilla (簡儀, Jianyi) of the Yuan dynasty. These two instruments were equipped with several rings, and the rings of one were similar both in size and in scale to those of the other. Using the classic method of drawing the scale on the circumference of a ring, we analyze the scales of the Small Simplified Armillary Sphere and the Sun-and-Stars Time-Determining Instrument. Like the scale feature of the Simplified Armilla, we find that these two instruments selected the specific circumference which can be drawn by two kinds of scales. If Joseon`s astronomical instruments is applied by the dual scale drawing on one circumference, we suggest that 3.14 was used as the ratio of the circumference of circle, not 3 like China, when the ring`s size was calculated in that time. From the size of Hundred-interval disk of the extant Simplified Sundial in Korea, we make a conclusion that the three rings` diameter of the Sun-and-Stars Time-Determining Instrument described in the Sejiong Sillok (世宗實錄, Veritable Records of the King Sejong) refers to that of the middle circle of every ring, not the outer circle. As analyzing the degree of 28 lunar lodges (lunar mansions) in the equator written by Chiljeongsan-naepyeon (七政算內篇, the Inner Volume of Calculation of the Motions of the Seven Celestial Determinants), we also obtain the result that the scale of the Celestial-circumference-degree in the Small Simplified Armillary Sphere was made with a scale error about 0.1 du in root mean square (RMS).
Deep data fusion method for missile-borne inertial/celestial system
NASA Astrophysics Data System (ADS)
Zhang, Chunxi; Chen, Xiaofei; Lu, Jiazhen; Zhang, Hao
2018-05-01
Strap-down inertial-celestial integrated navigation system has the advantages of autonomy and high precision and is very useful for ballistic missiles. The star sensor installation error and inertial measurement error have a great influence for the system performance. Based on deep data fusion, this paper establishes measurement equations including star sensor installation error and proposes the deep fusion filter method. Simulations including misalignment error, star sensor installation error, IMU error are analyzed. Simulation results indicate that the deep fusion method can estimate the star sensor installation error and IMU error. Meanwhile, the method can restrain the misalignment errors caused by instrument errors.
NASA Astrophysics Data System (ADS)
Sandrik, Suzannah
Optimal solutions to the impulsive circular phasing problem, a special class of orbital maneuver in which impulsive thrusts shift a vehicle's orbital position by a specified angle, are found using primer vector theory. The complexities of optimal circular phasing are identified and illustrated using specifically designed Matlab software tools. Information from these new visualizations is applied to explain discrepancies in locally optimal solutions found by previous researchers. Two non-phasing circle-to-circle impulsive rendezvous problems are also examined to show the applicability of the tools developed here to a broader class of problems and to show how optimizing these rendezvous problems differs from the circular phasing case.
Lack of access to health care for African indigents: a social exclusion perspective
2013-01-01
Background Lack of access to health care is a persistent condition for most African indigents, to which the common technical approach of targeting initiatives is an insufficient antidote. To overcome the standstill, an integrated technical and political approach is needed. Such policy shift is dependent on political support, and on alignment of international and national actors. We explore if the analytical framework of social exclusion can contribute to the latter. Methods We produce a critical and evaluative account of the literature on three themes: social exclusion, development policy, and indigence in Africa–and their interface. First, we trace the concept of social exclusion as it evolved over time and space in policy circles. We then discuss the relevance of a social exclusion perspective in developing countries. Finally, we apply this perspective to Africa, its indigents, and their lack of access to health care. Results The concept of social exclusion as an underlying process of structural inequalities has needed two decades to find acceptance in international policy circles. Initial scepticism about the relevance of the concept in developing countries is now giving way to recognition of its universality. For a variety of reasons however, the uptake of a social exclusion perspective in Africa has been limited. Nevertheless, social exclusion as a driver of poverty and inequity in Africa is evident, and manifestly so in the case of the African indigents. Conclusion The concept of social exclusion provides a useful framework for improved understanding of origins and persistence of the access problem that African indigents face, and for generating political space for an integrated approach. PMID:24238000
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hodge, B. M.; Lew, D.; Milligan, M.
2013-01-01
Load forecasting in the day-ahead timescale is a critical aspect of power system operations that is used in the unit commitment process. It is also an important factor in renewable energy integration studies, where the combination of load and wind or solar forecasting techniques create the net load uncertainty that must be managed by the economic dispatch process or with suitable reserves. An understanding of that load forecasting errors that may be expected in this process can lead to better decisions about the amount of reserves necessary to compensate errors. In this work, we performed a statistical analysis of themore » day-ahead (and two-day-ahead) load forecasting errors observed in two independent system operators for a one-year period. Comparisons were made with the normal distribution commonly assumed in power system operation simulations used for renewable power integration studies. Further analysis identified time periods when the load is more likely to be under- or overforecast.« less
Discrete distributed strain sensing of intelligent structures
NASA Technical Reports Server (NTRS)
Anderson, Mark S.; Crawley, Edward F.
1992-01-01
Techniques are developed for the design of discrete highly distributed sensor systems for use in intelligent structures. First the functional requirements for such a system are presented. Discrete spatially averaging strain sensors are then identified as satisfying the functional requirements. A variety of spatial weightings for spatially averaging sensors are examined, and their wave number characteristics are determined. Preferable spatial weightings are identified. Several numerical integration rules used to integrate such sensors in order to determine the global deflection of the structure are discussed. A numerical simulation is conducted using point and rectangular sensors mounted on a cantilevered beam under static loading. Gage factor and sensor position uncertainties are incorporated to assess the absolute error and standard deviation of the error in the estimated tip displacement found by numerically integrating the sensor outputs. An experiment is carried out using a statically loaded cantilevered beam with five point sensors. It is found that in most cases the actual experimental error is within one standard deviation of the absolute error as found in the numerical simulation.
New double-byte error-correcting codes for memory systems
NASA Technical Reports Server (NTRS)
Feng, Gui-Liang; Wu, Xinen; Rao, T. R. N.
1996-01-01
Error-correcting or error-detecting codes have been used in the computer industry to increase reliability, reduce service costs, and maintain data integrity. The single-byte error-correcting and double-byte error-detecting (SbEC-DbED) codes have been successfully used in computer memory subsystems. There are many methods to construct double-byte error-correcting (DBEC) codes. In the present paper we construct a class of double-byte error-correcting codes, which are more efficient than those known to be optimum, and a decoding procedure for our codes is also considered.
Guerrini, A M; Ascenzioni, F; Tribioli, C; Donini, P
1985-01-01
Linear plasmids were constructed by adding telomeres prepared from Tetrahymena pyriformis rDNA to a circular hybrid Escherichia coli-yeast vector and transforming Saccharomyces cerevisiae. The parental vector contained the entire 2 mu yeast circle and the LEU gene from S. cerevisiae. Three transformed clones were shown to contain linear plasmids which were characterized by restriction analysis and shown to be rearranged versions of the desired linear plasmids. The plasmids obtained were imperfect palindromes: part of the parental vector was present in duplicated form, part as unique sequences and part was absent. The sequences that had been lost included a large portion of the 2 mu circle. The telomeres were approximately 450 bp longer than those of T. pyriformis. DNA prepared from transformed S. cerevisiae clones was used to transform Schizosaccharomyces pombe. The transformed S. pombe clones contained linear plasmids identical in structure to their linear parents in S. cerevisiae. No structural re-arrangements or integration into S. pombe was observed. Little or no telomere growth had occurred after transfer from S. cerevisiae to S. pombe. A model is proposed to explain the genesis of the plasmids. Images Fig. 1. Fig. 2. Fig. 4. PMID:3896773
Poleward energy transport: is the standard definition physically relevant at all time scales?
NASA Astrophysics Data System (ADS)
Liang, Minyi; Czaja, Arnaud; Graversen, Rune; Tailleux, Remi
2018-03-01
Poleward energy transport in the atmosphere and oceans constitutes an important branch of the global energy budget, and its role in the climate system has been the subject of many studies. In the atmosphere, the transport is affected by "eddies" and large scale meridional cells, both with zero net mass transport across latitude circles, but also partly by processes associated with a net transport of mass across latitude circles. The latter must cease to operate in steady state, but they may be significant when time variability of the heat budget is considered. Indeed, examination of reanalysis data on short (daily to monthly) timescales shows that mass variations on these timescales result in surprisingly large fluctuations (in excess of 10^{15} W = 1 PW) in the poleward heat transport. These fluctuations are referred to as "extensive", for they primarily alter the mass integrated energy of the region considered, but not its averaged value. It is suggested that extensive fluctuations mask more meaningful climate signals present in the heat transport variability on monthly and interannual timescales, and a new formulation is proposed to isolate the latter. This new formulation is applied successfully to reanalysis data and climate model simulations.
Poleward Energy Transport: Is the Standard Definition Physically Relevant at All Time Scales?
NASA Astrophysics Data System (ADS)
Liang, M.; Czaja, A.; Graversen, R.; Tailleux, R.
2017-12-01
Poleward energy transport in the atmosphere and oceans constitutes an important branch of the global energy budget, and its role in the climate system has been the subject of many studies. In the atmosphere, the transport is affected by ''eddies'' and large scale meridional cells, both with zero net mass transport across latitude circles, but also partly by processes associated with a net transport of mass across latitude circles. The latter must cease to operate in steady state, but they may be significant when time variability of the heat budget is considered. Indeed, examination of reanalysis data on short (daily to monthly) timescales shows that mass variations on these timescales result in surprisingly large fluctuations (in excess of 1015W = 1PW) in the poleward heat transport. These fluctuations are referred to as ''extensive'', for they primarily alter the mass integrated energy of the region considered, but not its averaged value. It is suggested that extensive fluctuations mask more meaningful climate signals present in the heat transport variability, and a new formulation is proposed to isolate the latter. This new formulation is applied successfully to reanalysis data and climate model simulations.
NASA Astrophysics Data System (ADS)
Warrington, E. M.; Stocker, A. J.; Siddle, D. R.; Hallam, J.; Al-Behadili, H. A. H.; Zaalov, N. Y.; Honary, F.; Rogers, N. C.; Boteler, D. H.; Danskin, D. W.
2016-07-01
There is a need for improved techniques for nowcasting and forecasting (over several hours) HF propagation at northerly latitudes to support airlines operating over the increasingly popular trans-polar routes. In this paper the assimilation of real-time measurements into a propagation model developed by the authors is described, including ionosonde measurements and total electron content (TEC) measurements to define the main parameters of the ionosphere. The effects of D region absorption in the polar cap and auroral regions are integrated with the model through satellite measurements of the flux of energetic solar protons (>1 MeV) and the X-ray flux in the 0.1-0.8 nm band, and ground-based magnetometer measurements which form the Kp and Dst indices of geomagnetic activity. The model incorporates various features (e.g., convecting patches of enhanced plasma density) of the polar ionosphere that are, in particular, responsible for off-great circle propagation and lead to propagation at times and frequencies not expected from on-great circle propagation alone. The model development is supported by the collection of HF propagation measurements over several paths within the polar cap, crossing the auroral oval, and along the midlatitude trough.
Traditional and western healing practices for alcoholism in American Indians and Alaska Natives.
Abbott, P J
1998-11-01
The American Indian and Alaska Native population is a culturally diverse population with a current census of 1,959,000. Prior to White contact, there was historically little use of alcoholic beverages except for American Indians in the Southwest. After White contact, use and misuse of alcohol escalated rapidly; however, the prevalence, patterns, and problems of drinking alcoholic beverages vary enormously even in tribes closely linked geographically. American Indians and Alaska Natives have preserved and revitalized a number of traditional healing practices and applied these to the treatment of alcohol-related problems. These healing practices include the following: nativistic movements, sacred dances, sweat lodges, talking circle, four circles, and cultural enhancement programs. Additionally, Western treatment approaches have been applied in the treatment of problems related to alcohol, such as medication for detoxification, disulfiram (Antabuse), Alcoholics Anonymous, and behavioral interventions. Several investigators have completed a small number of naturalistic follow-up studies, but no one has undertaken a randomized controlled trial looking at specific methods of alcohol treatment in American Indians or Alaska Natives. American Indian and Alaska Native communities have adapted and integrated both Traditional and Western approaches to fit their own unique sociocultural needs.
A new look at the Feynman ‘hodograph’ approach to the Kepler first law
NASA Astrophysics Data System (ADS)
Cariñena, José F.; Rañada, Manuel F.; Santander, Mariano
2016-03-01
Hodographs for the Kepler problem are circles. This fact, known for almost two centuries, still provides the simplest path to derive the Kepler first law. Through Feynman’s ‘lost lecture’, this derivation has now reached a wider audience. Here we look again at Feynman’s approach to this problem, as well as the recently suggested modification by van Haandel and Heckman (vHH), with two aims in mind, both of which extend the scope of the approach. First we review the geometric constructions of the Feynman and vHH approaches (that prove the existence of elliptic orbits without making use of integral calculus or differential equations) and then extend the geometric approach to also cover the hyperbolic orbits (corresponding to E\\gt 0). In the second part we analyse the properties of the director circles of the conics, which are used to simplify the approach, and we relate with the properties of the hodographs and Laplace-Runge-Lenz vector the constant of motion specific to the Kepler problem. Finally, we briefly discuss the generalisation of the geometric method to the Kepler problem in configuration spaces of constant curvature, i.e. in the sphere and the hyperbolic plane.
Errors prevention in manufacturing process through integration of Poka Yoke and TRIZ
NASA Astrophysics Data System (ADS)
Helmi, Syed Ahmad; Nordin, Nur Nashwa; Hisjam, Muhammad
2017-11-01
Integration of Poka Yoke and TRIZ is a method of solving problems by using a different approach. Poka Yoke is a trial and error method while TRIZ is using a systematic approach. The main purpose of this technique is to get rid of product defects by preventing or correcting errors as soon as possible. Blame the workers for their mistakes is not the best way, but the work process should be reviewed so that every workers behavior or movement may not cause errors. This study is to demonstrate the importance of using both of these methods in which everyone in the industry needs to improve quality, increase productivity and at the same time reducing production cost.
Cheng, Jianhua; Chen, Daidai; Sun, Xiangyu; Wang, Tongda
2015-02-04
To obtain the absolute position of a target is one of the basic topics for non-cooperated target tracking problems. In this paper, we present a simultaneously calibration method for an Inertial navigation system (INS)/Global position system (GPS)/Laser distance scanner (LDS) integrated system based target positioning approach. The INS/GPS integrated system provides the attitude and position of observer, and LDS offers the distance between the observer and the target. The two most significant errors are taken into jointly consideration and analyzed: (1) the attitude measure error of INS/GPS; (2) the installation error between INS/GPS and LDS subsystems. Consequently, a INS/GPS/LDS based target positioning approach considering these two errors is proposed. In order to improve the performance of this approach, a novel calibration method is designed to simultaneously estimate and compensate these two main errors. Finally, simulations are conducted to access the performance of the proposed target positioning approach and the designed simultaneously calibration method.
Analysis of the Accuracy of Ballistic Descent from a Circular Circumterrestrial Orbit
NASA Astrophysics Data System (ADS)
Sikharulidze, Yu. G.; Korchagin, A. N.
2002-01-01
The problem of the transportation of the results of experiments and observations to Earth every so often appears in space research. Its simplest and low-cost solution is the employment of a small ballistic reentry spacecraft. Such a spacecraft has no system of control of the descent trajectory in the atmosphere. This can result in a large spread of landing points, which make it difficult to search for the spacecraft and very often a safe landing. In this work, a choice of a compromise scheme of the flight is considered, which includes the optimum braking maneuver, adequate conditions of the entry into the atmosphere with limited heating and overload, and also the possibility of landing within the limits of a circle with a radius of 12.5 km. The following disturbing factors were taken into account in the analysis of the accuracy of landing: the errors of the braking impulse execution, the variations of the atmosphere density and the wind, the error of the specification of the ballistic coefficient of the reentry spacecraft, and a displacement of its center of mass from the symmetry axis. It is demonstrated that the optimum maneuver assures the maximum absolute value of the reentry angle and the insensitivity of the trajectory of descent with respect to small errors of orientation of the braking engine in the plane of the orbit. It is also demonstrated that the possible error of the landing point due to the error of specification of the ballistic coefficient does not depend (in the linear approximation) upon its value and depends only upon the reentry angle and the accuracy of specification of this coefficient. A guided parachute with an aerodynamic efficiency of about two should be used at the last leg of the reentry trajectory. This will allow one to land in a prescribed range and to produce adequate conditions for the interception of the reentry spacecraft by a helicopter in order to prevent a rough landing.
NASA Astrophysics Data System (ADS)
Zhu, Jing; Wang, Xingshu; Wang, Jun; Dai, Dongkai; Xiong, Hao
2016-10-01
Former studies have proved that the attitude error in a single-axis rotation INS/GPS integrated system tracks the high frequency component of the deflections of the vertical (DOV) with a fixed delay and tracking error. This paper analyses the influence of the nominal process noise covariance matrix Q on the tracking error as well as the response delay, and proposed a Q-adjusting technique to obtain the attitude error which can track the DOV better. Simulation results show that different settings of Q lead to different response delay and tracking error; there exists optimal Q which leads to a minimum tracking error and a comparatively short response delay; for systems with different accuracy, different Q-adjusting strategy should be adopted. In this way, the DOV estimation accuracy of using the attitude error as the observation can be improved. According to the simulation results, the DOV estimation accuracy after using the Q-adjusting technique is improved by approximate 23% and 33% respectively compared to that of the Earth Model EGM2008 and the direct attitude difference method.
ERIC Educational Resources Information Center
Pambianchi, Laura Claypool
2017-01-01
State and national standards, including the Common Core State Standards, state that students should be expected to learn to discuss and analyze texts, comprehend ideas in increasingly complex texts, and justify their thinking. Literature circles are an instructional practice suggested by many educational writers as an instructional practice that…
Change in Ragweed Pollen Season, 1995-2015
This figure shows how the length of ragweed pollen season changed at 11 locations in the central United States and Canada between 1995 and 2015. Data were provided by Dr. Lewis Ziska of the U.S. Department of Agriculture, Agricultural Research Service. Red circles represent a longer pollen season; the blue circle represents a shorter season. Larger circles indicate larger changes. For more information: www.epa.gov/climatechange/science/indicators
Discovering Social Circles in Ego Networks (Author’s Manuscript)
2013-01-10
ego-network. We expect that circles are formed by densely-connected sets of alters ( Newman , 2006). However, different circles overlap heavily, i.e...umbrella of community detection (Lancichinetti and Fortunato, 2009a; Schaeffer, 2007; Leskovec et al., 2010; Porter et al., 2009; Newman , 2004). While...MCMC) sampler ( Newman and Barkema, 1999) which efficiently updates node-community memberships by ‘collapsing’ nodes that have common features and
Sets that Contain Their Circle Centers
ERIC Educational Resources Information Center
Martin, Greg
2008-01-01
Say that a subset S of the plane is a "circle-center set" if S is not a subset of a line, and whenever we choose three non-collinear points from S, the center of the circle through those three points is also an element of S. A problem appearing on the Macalester College Problem of the Week website stated that a finite set of points in the plane,…
1990-01-01
landing strip at Circle. Lodging is available primarily at Circle Hot Springs, approximately 30 miles southwest of Circle. In general, hiking, snowmobiling... timberline ), coniferous forest, and several widespread deciduous species. Coniferous and deciduous forest, alpine and deciduous scrub, shrub tundra, and...white and paper birch, quaking aspen, and balsam poplar. Common shrub species (above and below timberline ) are alder, willow, glandular birch
Carinelli, S; Kühnemund, M; Nilsson, M; Pividori, M I
2017-07-15
This work addresses the design of an Ebola diagnostic test involving a simple, rapid, specific and highly sensitive procedure based on isothermal amplification on magnetic particles with electrochemical readout. Ebola padlock probes were designed to detect a specific L-gene sequence present in the five most common Ebola species. Ebola cDNA was amplified by rolling circle amplification (RCA) on magnetic particles. Further re-amplification was performed by circle-to-circle amplification (C2CA) and the products were detected in a double-tagging approach using a biotinylated capture probe for immobilization on magnetic particles and a readout probe for electrochemical detection by square-wave voltammetry on commercial screen-printed electrodes. The electrochemical genosensor was able to detect as low as 200 ymol, corresponding to 120 cDNA molecules of L-gene Ebola virus with a limit of detection of 33 cDNA molecules. The isothermal double-amplification procedure by C2CA combined with the electrochemical readout and the magnetic actuation enables the high sensitivity, resulting in a rapid, inexpensive, robust and user-friendly sensing strategy that offers a promising approach for the primary care in low resource settings, especially in less developed countries. Copyright © 2016 Elsevier B.V. All rights reserved.
Promoting retention, enabling success: Discovering the potential of student support circles.
Bass, Janice; Walters, Caroline; Toohill, Jocelyn; Sidebotham, Mary
2016-09-01
Retention of students is critical to education programs and future workforce. A mixed methods study evaluated student engagement within a Bachelor of Midwifery program and connection with career choice through participation in student support circles. Centred on the Five Senses of Success Framework (sense of capability, purpose, identity, resourcefulness and connectedness) and including four stages of engagement (creating space, preparing self, sharing stories, focused conversations), the circles support and develop student and professional identity. Of 80 students 43 (54%) provided responses to a two item survey assessed against a five point Likert scale to determine utility. Using a nominal group technique, student's voices gave rich insight into the personal and professional growth that participation in the student support circles provided. Evaluated as helpful to first year students in orientating to university study and early socialisation into the profession, the circles appear to influence the development of a strong sense of professional identity and personal midwifery philosophy based on the relational nature of the midwife being with woman rather than doing midwifery. This suggests that student support circles positively influence perceptions and expectations, contributing to a shared sense of purpose and discipline connection, for enhancing student retention and future workforce participation. Copyright © 2016 Elsevier Ltd. All rights reserved.